FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Basu, A Wentworth, SJ McKay, DS AF Basu, A Wentworth, SJ McKay, DS TI Submillimeter grain-size distribution of Apollo 11 soil 10084 SO METEORITICS & PLANETARY SCIENCE LA English DT Article AB Soil 10084 is the only representative soil sample from Apollo 11 and arguably one of the purest mare soils in the Apollo collection. It was wet sieved in 1970 and dry sieved in 1971 with different results. Therefore, some doubt about its grain-size distribution persists. We consider allocation inhomogeneity, if any, to be a minor cause for the discrepancy. Rather, the difference in methodology is likely to be the major cause for different results. We report the results of a new analysis of an allocation of 0.99 g using the contemporary method of wet sieving at Johnson Space Center; this method uses water instead of freon. Our results show that the mean grain size and sorting of the submillimeter fraction of soil 10084 are 4.28 phi (= 51 mum) and 2.23 phi (= 213 mum), respectively. A significant proportion (14.2%) of the soil is in the <10 m size range, which contrasts to previous determinations of 6.4% and 9.8%, respectively. The newly determined grain-size distribution is skewed towards the finest grain sizes. This result is more compatible with the high maturity of this soil than the results of previous determinations. C1 Indiana Univ, Dept Geol Sci, Bloomington, IN 47405 USA. Lockheed Martin, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Basu, A (reprint author), Indiana Univ, Dept Geol Sci, Bloomington, IN 47405 USA. NR 21 TC 5 Z9 6 U1 1 U2 1 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JAN PY 2001 VL 36 IS 1 BP 177 EP 181 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 414EH UT WOS:000167652600015 ER PT B AU Hand, C AF Hand, C BE Valafar, F TI Epicenter location by analysis of interictal spikes SO METMBS'01: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MATHEMATICS AND ENGINEERING TECHNIQUES IN MEDICINE AND BIOLOGICAL SCIENCES LA English DT Proceedings Paper CT International Conference on Mathematics and Engineering Techniques in Medicine and Biological Sciences CY JUN 25-28, 2001 CL LAS VEGAS, NV SP Comp Sci Res, Educ & Appl Press, Int Technol Inst, Korea Informat Proc Soc, World Acad Sci Informat Technol, PACT Corp, Comp Vis Res & Appl Tech, Java High Performance Comp Res Grp, Sundance Digital Signal Proc Inc DE epilepsy; MEG; interictal spikes; artificial neural networks AB Surgical resectioning can cure some forms of epilepsy. The precise location of the area of excision is currently determined with a network, of surgically implanted subdural electrodes. This means that the cure entails two surgical procedures. one to implant the electrode array that precisely locates the epicenter, and another surgery to remove the epicenter. This paper outlines an experimental Diagnostic Software System (DSS) that will use Artificial Neural Network (ANN) analysis of Magnetoencephalographic (MEG) data to eliminate the first of these surgical procedures. The MEG recording is a quick and painless process that requires no surgery. This approach has the potential to save time, reduce patient discomfort, and eliminates a painful and potentially dangerous surgical step in the treatment procedure. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Hand, C (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-77-7 PY 2001 BP 1 EP 6 PG 6 WC Biochemical Research Methods; Computer Science, Interdisciplinary Applications; Engineering, Biomedical SC Biochemistry & Molecular Biology; Computer Science; Engineering GA BT48G UT WOS:000173108700001 ER PT S AU Birur, GC Sur, TW Paris, AD Shakkottai, P Green, AA Haapanen, SI AF Birur, GC Sur, TW Paris, AD Shakkottai, P Green, AA Haapanen, SI BE Mastrangelo, CH Becker, H TI Micro/nano spacecraft thermal control using a MEMS-based pumped liquid cooling system SO MICROFLUIDICS AND BIOMEMS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Microfluidics and BioMEMS CY OCT 22-24, 2001 CL SAN FRANCISCO, CA SP SPIE, SolidState Technol, Sandia Natl Labs, Jet Propuls Lab DE microchannel; microspacecraft; thermal control; electronics cooling; heat exchanger ID HEAT AB The thermal control of future micro/nano spacecraft will be challenging due to power densities which are expected to exceed 25 W/cm(2). Advanced thermal control concepts and technologies are essential to keep their payload within allowable temperature limits and also to provide accurate temperature control required by the science instruments and engineering equipment on board. To this end, a MEMS-based pumped liquid cooling system is being investigated at the Jet Propulsion Laboratory (JPL). The mechanically pumped cooling system consists of a working fluid circulated through microchannels by a micropump. Microchannel heat exchangers have been designed and fabricated in silicon at JPL and currently are being tested for hydraulic and thermal performance in simulated microspacecraft heat loads using de ionized water as the working fluid. The microchannels are 50 microns deep with widths ranging from 50 to 100 microns. The hydraulic and thermal test data was used for numerical model validation. Optimization studies are being conducted using these numerical models on various microchannel configurations, working fluids, and micropump technologies. This paper presents background on the need for pumped liquid cooling systems for future micro/nano spacecraft and results from this ongoing numerical and experimental investigation. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Gajanana.C.Birur@jpl.nasa.gov; TRICIA.W.SUR@saic.com NR 14 TC 7 Z9 7 U1 0 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4288-7 J9 PROC SPIE PY 2001 VL 4560 BP 196 EP 206 DI 10.1117/12.443059 PG 11 WC Engineering, Mechanical; Optics SC Engineering; Optics GA BU48Q UT WOS:000176126600026 ER PT S AU Walker, EM Buckley, DJ Boyall, NM Durose, K Grasza, K Szczerbakow, A Palosz, W AF Walker, EM Buckley, DJ Boyall, NM Durose, K Grasza, K Szczerbakow, A Palosz, W BE Cullis, AG Hutchison, JL TI Spatial analysis of dislocation distribution as a means of assessing crystal growth processes SO MICROSCOPY OF SEMICONDUCTING MATERIALS 2001 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT Royal-Microscopical-Society Conference on Microscopy of Semiconducting Materials CY MAR 25-29, 2001 CL UNIV OXFORD, OXFORD, ENGLAND SP Royal Microscop Soc, Inst Phys, Electron Microscopy & Anal Grp, Mat Res Soc HO UNIV OXFORD ID CDTE AB Statistical methods were used to evaluate quantitatively the distribution of etch pits on semiconductor wafers. Comparison with Poisson distribution and the form of the radial autocorrelation function allowed the tendency to dislocation clustering (polygonisation) to be evaluated. Samples of CdTe grown by the Bridgman method were compared with those grown by three vapour methods; the former exhibits the stronger dislocation clustering. C1 Univ Durham, Dept Phys, Durham DH1 3LE, England. Polish Acad Sci, Inst Phys, PL-02668 Warsaw, Poland. USRA, George C Marshall Space Flight Ctr, Huntsville, AL USA. RP Walker, EM (reprint author), Univ Durham, Dept Phys, South Rd, Durham DH1 3LE, England. RI Durose, Ken/E-2617-2013 NR 4 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0951-3248 BN 0-7503-0818-4 J9 INST PHYS CONF SER PY 2001 IS 169 BP 215 EP 218 PG 4 WC Microscopy; Physics, Multidisciplinary SC Microscopy; Physics GA BU59T UT WOS:000176465200045 ER PT S AU Eidmann, G Offermann, D Jarisch, M Preusse, P Eckermann, SD Schmidlin, FJ AF Eidmann, G Offermann, D Jarisch, M Preusse, P Eckermann, SD Schmidlin, FJ BE Riese, M Spang, R Swenson, GR Espy, PJ TI Horizontal temperature variability in the stratosphere: Global variations inferred from CRISTA data SO MIDDLE ATMOSPHERE TEMPORAL AND SPATIAL STRUCTURES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT C2 3/A1 4 Symposium of COSPAR Scientific Commission C held at 33rd COSPAR Scientific Assembly CY JUL 16-23, 2000 CL WARSAW, POLAND SP Deutsch Zentrum Luft Raumfahrt E U, European Space Agcy, Natl Aeronaut & Space Adm, Stratospher Process & Their Role Climate, Comm Space Res ID CRYOGENIC INFRARED SPECTROMETERS; TELESCOPES AB In two separate orbital campaigns (November, 1994 and August, 1997), the Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere (CRISTA) instrument acquired global stratospheric data of high accuracy and high spatial resolution. The standard limb-scanned CRISTA measurements resolved atmospheric spatial structures with vertical dimensions greater than or equal to 1.5-2 km and horizontal dimensions greater than or equal to 100-200 km. A fluctuation analysis of horizontal temperature distributions derived from these data is presented. This method is somewhat complementary to conventional power-spectral analysis techniques. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Berg Univ Gesamthsch Wuppertal, Dept Phys, D-42097 Wuppertal, Germany. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, Observ Sci Branch, Wallops Flight Facil, Wallops Isl, VA 23337 USA. RP Eidmann, G (reprint author), Berg Univ Gesamthsch Wuppertal, Dept Phys, Gauss Str 20, D-42097 Wuppertal, Germany. RI Spang, Reinhold/A-2738-2013; Preusse, Peter/A-1193-2013 OI Spang, Reinhold/0000-0002-2483-5761; Preusse, Peter/0000-0002-8997-4965 NR 8 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 10 BP 1641 EP 1646 DI 10.1016/S0273-1177(01)00229-0 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT13W UT WOS:000172045800004 ER PT S AU Bennett, AC Omidvar, K AF Bennett, AC Omidvar, K BE Riese, M Spang, R Swenson, GR Espy, PJ TI Alternative method for the thermospheric atomic oxygen density determination SO MIDDLE ATMOSPHERE TEMPORAL AND SPATIAL STRUCTURES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT C2 3/A1 4 Symposium of COSPAR Scientific Commission C held at 33rd COSPAR Scientific Assembly CY JUL 16-23, 2000 CL WARSAW, POLAND SP Deutsch Zentrum Luft Raumfahrt E U, European Space Agcy, Natl Aeronaut & Space Adm, Stratospher Process & Their Role Climate, Comm Space Res ID COLLISION CROSS-SECTION; O+-O; WIND MEASUREMENTS; MILLSTONE HILL; FREQUENCY; RADAR AB Atomic oxygen density in the upper thermosphere (similar to 300 km) can be calculated using ground based incoherent scatter radar and Fabry-Perot interferometer measurements. Burnside et al. (1991) was the first to try this method, but Buonsanto et al. (1997) provided an extensive treatment of the method in 1997. This paper further examines the method using 46 nights of data collected over six years and the latest information on the oxygen collision frequency. The method is compared with the MSIS-86 atomic oxygen prediction values, which are based upon in situ rocket born and satellite measurements from the 70's to the mid-80's. In general, the method supports the MSIS-86 model, but indicates several areas of discrepancy. Furthermore, no direct correlation is found between the geomagnetic conditions and the difference between the method and MSIS-86 predictions. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Taylor Univ, Dept Phys, Upland, IN 46989 USA. NASA, Goddard Space Flight Ctr, Data Assimilat Off, Greenbelt, MD 20771 USA. RP Bennett, AC (reprint author), Taylor Univ, Dept Phys, Upland, IN 46989 USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 10 BP 1685 EP 1690 DI 10.1016/S0273-1177(01)00236-8 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT13W UT WOS:000172045800011 ER PT B AU Hinshaw, G AF Hinshaw, G BE Banday, AJ Zaroubi, S Bartelmann, M TI Data analysis for the microwave anisotropy probe (MAP) mission SO MINING THE SKY SE ESO ASTROPHYSICS SYMPOSIA LA English DT Proceedings Paper CT MPA/ESO/MPE Workshop on Mining the Sky CY JUL 31-AUG 04, 2000 CL GARCHING, GERMANY SP MPA, ESO, MPE ID POWER SPECTRUM; RADIOMETER; EMISSION AB We present an overview of the upcoming Microwave Anisotropy Probe (MAP) mission, with an emphasis on those aspects of the mission that simplify the data analysis. The method used to make sky maps from the differential temperature data is reviewed and we present some of the noise properties expected from these maps. An overview of the method we plan to use to mine the angular power spectrum from the mega-pixel sky maps closes the paper. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hinshaw, G (reprint author), NASA, Goddard Space Flight Ctr, Code 685, Greenbelt, MD 20771 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-42468-7 J9 ESO ASTROPHY SYMP PY 2001 BP 447 EP 457 DI 10.1007/10849171_57 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT22Q UT WOS:000172334800057 ER PT B AU Borne, KD AF Borne, KD BE Banday, AJ Zaroubi, S Bartelmann, M TI Data mining in astronomical databases SO MINING THE SKY SE ESO ASTROPHYSICS SYMPOSIA LA English DT Proceedings Paper CT MPA/ESO/MPE Workshop on Mining the Sky CY JUL 31-AUG 04, 2000 CL GARCHING, GERMANY SP MPA, ESO, MPE AB A Virtual Observatory (VO) will enable transparent and efficient access, search, retrieval, and visualization of data across multiple data repositories, which are generally heterogeneous and distributed. Aspects of data mining that apply to a variety of science user scenarios with a VO are reviewed. C1 NASA, Goddard Space Flight Ctr, Raytheon iTSS, Greenbelt, MD 20771 USA. RP Borne, KD (reprint author), NASA, Goddard Space Flight Ctr, Raytheon iTSS, Code 631, Greenbelt, MD 20771 USA. NR 4 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-42468-7 J9 ESO ASTROPHY SYMP PY 2001 BP 671 EP 673 DI 10.1007/10849171_88 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT22Q UT WOS:000172334800088 ER PT S AU Fluckiger, L Nguyen, L AF Fluckiger, L Nguyen, L BE Choset, HM Gage, DW Stein, MR TI A generic force-server for haptic devices SO MOBILE ROBOTS XV AND TELEMANIPULATOR AND TELEPRESENCE TECHNOLOGIES VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Mobile Robots XV and Telemanipulator and Telepresence Technologies VII CY NOV 05-06, 2000 CL BOSTON, MA SP SPIE DE force feedback; haptic device; virtual reality; force server; robot manipulator/rover simulation AB This paper presents a novel architecture allowing a generic force-feedback device to be used by different software tools dedicated to teleoperation and mission planning. This architecture relies on a "force-server" program running between the real-time controller of the haptic device and a set of applications using it. Possible applications include mission ground control system interfaces, telemetry systems coming back from real robots, or external simulation programs. The force-server concept is based on a high-level description of the forces to be generated. This description consists of spatial constraints defined by their type (point, line, plane and mesh), position and orientation. A force profile (space and/or time dependent) is assigned to each constraint. This description enables the generation of complex fields of forces by combining basic constraints. The advantage of this method is that an application can send force updates by simply modifying several parameters of the constraint. Between two updates (from the application) the force-server is able to continously compute new forces corresponding to the actual position of the device handle. This approach enables the control loop of the force feedback device to easily run at 500Hz when the application may send updates only at 25Hz. This novel method widens the use of force-feedback devices by providing a common interface to the different applications, and allowing multiple clients to use the same haptic device. A testbed using a 6 DOF haptic device has been developed. The device generates forces coming simultaneously from three different sources: a Java interface to experiment various force profiles, a rover simulator, and a scientific visualization tool used during planetary missions. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Fluckiger, L (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3860-X J9 P SOC PHOTO-OPT INS PY 2001 VL 4195 BP 379 EP 387 PG 9 WC Automation & Control Systems; Robotics; Optics SC Automation & Control Systems; Robotics; Optics GA BS25T UT WOS:000169199700038 ER PT B AU Raj, SV AF Raj, SV BE Lesuer, DR Srivatsan, TS TI Formulation of a substructure-based creep model SO MODELING THE PERFORMANCE ENGINEERING STRUCTURAL MATERIALS II LA English DT Proceedings Paper CT Symposium on Modelling the Performance of Engineering Structural Materials held at the 2001 TMS Fall Meeting CY NOV 04-08, 2001 CL INDIANAPOLIS, IN SP Minerals Met & Mat Soc, Mat Informat Soc ID POWER-LAW; DISLOCATION; DEFORMATION; TEMPERATURE; CRYSTALS; PATTERNS; METALS; ENERGY AB A large body of experimental data accumulated in the power-law creep regime over the last several decades has revealed a remarkable similarity in the creep behavior of many materials varying from metals, intermetallics, ionic salts, ceramics to geological materials. Although several creep models have been proposed, they are largely limited in their inability to rationalize many experimental observations. A universal approach to creep modeling is proposed in this paper with a long term objective of impacting engineering design. First, creep microstructural observations are qualitatively rationalized in terms of a bifurcation diagram. Next, the use of nonlinear dislocation dynamics in creep modeling is advocated to rationalize the observed diversity in the creep substructures, and a simple technique for formulating these equations is discussed. A method is proposed for scaling-up the dislocation substructure evolution models by coupling them to a viscoplastic model through the volume fractions of the "hard" and "soft" phases. This coupling is shown to lead to the stress-subgrain size relationship in a simple and natural way. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Raj, SV (reprint author), NASA, Glenn Res Ctr, 21000 Brookpark Rd, Cleveland, OH 44135 USA. NR 33 TC 0 Z9 0 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-504-2 PY 2001 BP 13 EP 30 PG 18 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Metallurgy & Metallurgical Engineering; Materials Science GA BT38V UT WOS:000172834800002 ER PT J AU Schofield, D Mjolsness, E Buckley, J Wold, B Triche, TJ AF Schofield, D Mjolsness, E Buckley, J Wold, B Triche, TJ TI Gene expression patterns in pediatric rhabdomyosarcoma. SO MODERN PATHOLOGY LA English DT Meeting Abstract C1 Univ So Calif, Keck Sch Med, Los Angeles, CA USA. CALTECH, JPL, Pasadena, CA 91125 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK ST, 9TH FLR, NEW YORK, NY 10013-1917 USA SN 0893-3952 EI 1530-0285 J9 MODERN PATHOL JI Mod. Pathol. PD JAN PY 2001 VL 14 IS 1 MA 34 BP 6P EP 6P PG 1 WC Pathology SC Pathology GA 396EB UT WOS:000166622401451 ER PT J AU Schofield, D Mjolsness, E Buckley, J Wold, B Triche, TJ AF Schofield, D Mjolsness, E Buckley, J Wold, B Triche, TJ TI Gene expression patterns in pediatric sarcomas as a predictor of clinical outcome SO MODERN PATHOLOGY LA English DT Meeting Abstract C1 Univ So Calif, Keck Sch Med, Los Angeles, CA USA. CALTECH, JPL, Pasadena, CA 91125 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK ST, 9TH FLR, NEW YORK, NY 10013-1917 USA SN 0893-3952 EI 1530-0285 J9 MODERN PATHOL JI Mod. Pathol. PD JAN PY 2001 VL 14 IS 1 MA 87 BP 18A EP 18A PG 1 WC Pathology SC Pathology GA 396EB UT WOS:000166622400095 ER PT S AU Mott, DB Aslam, S Blumenstock, KA Fettig, RK Franz, D Kutyrev, AS Li, MJ Monroy, CJ Moseley, SH Schwinger, DS AF Mott, DB Aslam, S Blumenstock, KA Fettig, RK Franz, D Kutyrev, AS Li, MJ Monroy, CJ Moseley, SH Schwinger, DS BE Motamedi, ME Goring, R TI Magnetically actuated microshutter arrays SO MOEMS AND MINIATURIZED SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on MOEMS and Miniaturized Systems II CY OCT 22-24, 2001 CL SAN FRANCISCO, CA SP SPIE, Semiconductor Equipment & Mat Int, SolidState Technol, Sandia Natl Labs, Jet Propuls Lab DE microshutter; magnetic actuation; DRIE; silicon nitride; transmissive mask AB Two-dimensional microshutter arrays are being developed at NASA Goddard Space Flight Center (GSFC) for the Next Generation Space Telescope (NGST) for use in the near-infrared region. Functioning as focal plane object selection devices, the microshutter arrays are 2-D programmable masks with high efficiency and high contrast. The NGST environment requires cryogenic operation at 45 K. Arrays are close-packed silicon nitride membranes with a unit cell size of 100x100 micrometer. Individual shutters are patterned with a torsion flexure permitting shutters to open 90 degrees with minimized mechanical stress concentration. The mechanical shutter arrays are fabricated with MEMS technologies. The processing includes a RIE front-etch to form shutters out of the nitride membrane, an anisotropic back-etch for wafer thinning, and a deep RIE (DRIE) back-etch down to the nitride shutter membrane to form frames and to relieve the shutters from the silicon substrate. A layer of magnetic material is deposited onto each shutter. Onto the side-wall of the support structure a metal layer is deposited that acts as a vertical hold electrode. Shutters are rotated into the support structure by means of an external magnet that is swept across the shutter array for opening. Addressing is performed through a scheme using row and column address lines on each chip and external addressing electronics. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Mott, DB (reprint author), NASA, Goddard Space Flight Ctr, Code 553, Greenbelt, MD 20771 USA. RI Aslam, Shahid/D-1099-2012 NR 8 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4289-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4561 BP 163 EP 170 DI 10.1117/12.443109 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT78T UT WOS:000174063500020 ER PT J AU An, I Oh, HK Paley, MS AF An, I Oh, HK Paley, MS TI Real-time spectroscopic ellipsometric studies of photo-assisted chemical processes SO MOLECULAR CRYSTALS AND LIQUID CRYSTALS LA English DT Article; Proceedings Paper CT 3rd Asian Symposium on Organized Molecular Films for Electronics and Photonics (ASOMF 3) CY JUL 09-12, 2000 CL HANYANG UNIV, SEOUL, SOUTH KOREA SP Korea Sci & Engn Fdn, Polymer Soc Korea, Molec Electr Div, Samsung Adv Inst Technol, LC Electr Inst Technol, Natl Program Tera Level Nanodevices, Sogang Univ, Pohang Univ Sci & Technol, Inje Univ, Study Grp Properties Photon & Microelectr Polymers Molec Design HO HANYANG UNIV DE ellipsometry; polydiacetylene; photo-assisted ID THIN-FILM AB Real-time spectroscopic ellipsometry was employed to characterize the photo-assisted growth of polydiacetylene films in solution. From regression analysis, the low growth rate of similar to3 Angstrom /min was obtained and the reduction of growth rate due to absorbing film was observed. The growth was strongly affected by the movement of solution indicating a reaction-limited process at film and solution boundary. C1 Hanyang Univ, Dept Phys, Ansan 425791, South Korea. NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35812 USA. RP An, I (reprint author), Hanyang Univ, Dept Phys, Ansan 425791, South Korea. NR 10 TC 1 Z9 1 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK,, ABINGDON OX14 4RN, OXON, ENGLAND SN 1058-725X J9 MOL CRYST LIQ CRYST JI Mol. Cryst. Liquid Cryst. PY 2001 VL 371 BP 313 EP 316 DI 10.1080/10587250108024749 PG 4 WC Crystallography SC Crystallography GA 503TK UT WOS:000172816400078 ER PT J AU Boccippio, DJ Cummins, KL Christian, HJ Goodman, SJ AF Boccippio, DJ Cummins, KL Christian, HJ Goodman, SJ TI Combined satellite- and surface-based estimation of the intracloud-cloud-to-ground lightning ratio over the continental United States SO MONTHLY WEATHER REVIEW LA English DT Article ID THUNDERSTORM CONVECTIVE REGIONS; DETECTION NETWORK UPGRADE; STROKE PEAK CURRENT; ELECTRICAL STRUCTURE; TORNADIC STORM; FLASH DENSITY; COUNT AB Four years of observations from the NASA Optical Transient Detector and Global Atmospherics National Lightning Detection Network are combined to determine the geographic distribution of the climatological intracloud-cloud-to-ground (CG) lightning ratio, termed Z, over the continental United States. The value of Z over this region is 2.64-2.94, with a standard deviation of 1.1-1.3 and anomalies as low as 1.0 or less over the Rocky and Appalachian Mountains and as high as 8-9 in the central-upper Great Plains. There is some indication that Z covaries with ground elevation, although the relationship is nonunique. Little evidence is found to support a latitudinal covariance. The dynamic range of local variability is comparable to the range of values cited by previous studies for latitudinal variation from the deep Tropics to midlatitudes. Local high Z anomalies in the Great Plains are coincident with anomalies in the climatological percentage of positive CG occurrence, as well as in the occurrence of large positive CGs characteristic of organized or severe storms. This suggests that storm type, morphology, and level of organization may dominate over environmental cofactors in the local determination of this ratio. C1 NASA, George C Marshall Space Flight Ctr, Global Hydrol & Climate Ctr, Huntsville, AL 35812 USA. Global Atmospher Inc, Tucson, AZ USA. RP Boccippio, DJ (reprint author), NASA, George C Marshall Space Flight Ctr, Global Hydrol & Climate Ctr, Huntsville, AL 35812 USA. OI Cummins, Kenneth/0000-0001-9871-691X NR 44 TC 162 Z9 168 U1 0 U2 15 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 1 BP 108 EP 122 DI 10.1175/1520-0493(2001)129<0108:CSASBE>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 393MZ UT WOS:000166475400006 ER PT J AU Fox-Rabinovitz, MS Takacs, LL Govindaraju, RC Suarez, MJ AF Fox-Rabinovitz, MS Takacs, LL Govindaraju, RC Suarez, MJ TI A variable-resolution stretched-grid general circulation model: Regional climate simulation SO MONTHLY WEATHER REVIEW LA English DT Article ID SHALLOW-WATER EQUATIONS; NORTH-AMERICAN DROUGHT; NUMERICAL WEATHER PREDICTION; LAGRANGIAN ATMOSPHERIC MODEL; GCM DYNAMICAL CORE; PRIMITIVE EQUATIONS; SOIL-MOISTURE; UNITED-STATES; GLOBAL-MODEL; 1988 DROUGHT AB The development of and results obtained with a variable-resolution stretched-grid GCM for the regional climate simulation mode are presented. A global variable-resolution stretched grid used in the study has enhanced horizontal resolution over the United States as the area of interest. The stretched-grid approach is an ideal tool for representing regional- to global-scale interactions. It is an alternative to the widely used nested-grid approach introduced over a decade ago as a pioneering step in regional climate modeling. The major results of the study are presented for the successful stretched-grid GCM simulation of the anomalous climate event of the 1988 U.S. summer drought. The straightforward (with no updates) 2-month simulation is performed with 60-km regional resolution. The major drought fields, patterns, and characteristics, such as the time-averaged 500-hPa heights, precipitation, and the low-level jet over the drought area, appear to be close to the verifying analyses for the stretched-grid simulation. In other words, the stretched-grid GCM provides an efficient downscaling over the area of interest with enhanced horizontal resolution, in spite of degradation of skill over the coarser resolution far away from the area of interest. It is also shown that the stretched-grid GCM skill is sustained over the area of interest throughout the simulation extended to 1 yr. The stretched-grid GCM, developed and tested in a simulation mode, is a viable tool for regional and subregional climate studies and applications. C1 Univ Maryland, ESSIC, Dept Meteorol, College Pk, MD 20742 USA. NASA, Data Assimilat Off, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Gen Sci Corp, Beltsville, MD USA. NASA, Atmospheres Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fox-Rabinovitz, MS (reprint author), Univ Maryland, ESSIC, Dept Meteorol, CSS Bldg, College Pk, MD 20742 USA. NR 60 TC 31 Z9 32 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 3 BP 453 EP 469 DI 10.1175/1520-0493(2001)129<0453:AVRSGG>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 408MB UT WOS:000167329000006 ER PT J AU Xue, M Lin, SJ AF Xue, M Lin, SJ TI Numerical equivalence of advection in flux and advective forms and quadratically conservative high-order advection schemes SO MONTHLY WEATHER REVIEW LA English DT Article ID MODEL; SIMULATION; EQUATIONS; ENSTROPHY AB In finite-difference representations of the conservation equations, the flux form of the advection terms is often preferred to the advective form because of the immediate conservation of advected quantity. The scheme can be designed to further conserve higher-order moments, for example, the kinetic energy, which is important to the suppression of nonlinear instability. It is pointed out here that in most cases an advective form that is numerically equivalent to the flux form can be found, for schemes based on centered difference. This is also true for higher-order schemes and is not restricted to a particular grid type. An advection scheme that is fourth-order accurate in space for uniform advective flows is proposed that conserves both first and second moments of the advected variable in a nonhydrostatic framework. The role of the elastic correction term in addition to the pure flux term in compressible nonhydrostatic models is also discussed. C1 Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. Univ Oklahoma, Ctr Anal & Predict Storms, Norman, OK 73019 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Xue, M (reprint author), Univ Oklahoma, Sch Meteorol, 100 E Boyd, Norman, OK 73019 USA. EM mxue@ou.edu RI Xue, Ming/F-8073-2011 OI Xue, Ming/0000-0003-1976-3238 NR 22 TC 7 Z9 7 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 3 BP 561 EP 565 DI 10.1175/1520-0493(2001)129<0561:NEOAIF>2.0.CO;2 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 408MB UT WOS:000167329000014 ER PT J AU Chao, WC Chen, BD AF Chao, WC Chen, BD TI The role of surface friction in tropical intraseasonal oscillation SO MONTHLY WEATHER REVIEW LA English DT Article ID MADDEN-JULIAN OSCILLATION; CUMULUS CONVECTION SCHEMES; GENERAL-CIRCULATION MODELS; EVAPORATION-WIND FEEDBACK; 40-50 DAY OSCILLATION; SUPER CLOUD CLUSTERS; PACIFIC WARM POOL; LOW-FREQUENCY; WAVE-CISK; SCALE CIRCULATIONS AB The role of surface friction in the tropical intraseasonal oscillation, or the Madden-Julian oscillation (MJO), is investigated by comparing two 4-yr integrations with the Goddard atmospheric general circulation model: one with the original model design with one added feature to enhance the intensity of the MJO and the other is identical but with surface friction in the Tropics replaced by its zonal mean value. This comparison indicates that in the second experiment the MJO not only still exists but also exists with similar intensity. The oft-cited frictional wave-CISK (FWC) interpretation for the origin of the MJO, which emphasizes the role of frictionally induced convergence in the surface layer, is reassessed in light of these experiments. The possibility of the MJO in the second experiment being forced by the middle latitudes is excluded by a third experiment. These experiments do not support one of the central ideas in FWC that surface friction plays an instability-enhancing role. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Seabrook, MD USA. RP Chao, WC (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 913, Greenbelt, MD 20771 USA. NR 50 TC 7 Z9 7 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 4 BP 896 EP 904 DI 10.1175/1520-0493(2001)129<0896:TROSFI>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 424VD UT WOS:000168253900018 ER PT J AU Lynn, BH Stauffer, DR Wetzel, PJ Tao, WK Alpert, P Perlin, N Baker, RD Munoz, R Boone, A Jia, YQ AF Lynn, BH Stauffer, DR Wetzel, PJ Tao, WK Alpert, P Perlin, N Baker, RD Munoz, R Boone, A Jia, YQ TI Improved simulation of Florida summer convection using the PLACE land model and a 1.5-order turbulence parameterization coupled to the Penn State-NCAR mesoscale model SO MONTHLY WEATHER REVIEW LA English DT Article ID LAYER CONVERGENCE LINES; LAKE-MICHIGAN OZONE; SEA-BREEZE FRONT; BOUNDARY-LAYER; SOUTH FLORIDA; DEEP CONVECTION; SOIL-MOISTURE; INITIATION; CLIMATE; SURFACE AB Three major modifications to the treatment of land surface processes in the Pennsylvania State University-National Center for Atmospheric Research mesoscale model MM5, are tested in a matrix of eight model experiments. Paired together in each dimension of the matrix are versions of the code with and without one of the changes. The three changes involve 1) a sophisticated land surface model [the Parameterization for Land-Atmosphere Convective Exchange (PLACE)], 2) the soil moisture and temperature initial conditions derived from running PLACE offline, and 3) a 1.5- order turbulent kinetic energy (TKE) turbulence boundary layer. The code without changes, defined as the control code, uses the most widely applied land surface, soil initialization, and boundary layer options found in the current MM5 community code. As an initial test of these modifications, a case was chosen in which they should have their greatest effect: conditions where heterogeneous surface forcing dominates over dynamic processes. The case chosen is one with widespread summertime moist convection, during the Convection and Precipitation Electrification Experiment (CaPE) in the middle of the Florida peninsula. Of the eight runs, the code with all three changes (labeled TKE-PLACE) demonstrates the best overall skill in terms of biases of the surface variables, rainfall, and percent and root-mean-square error of cloud cover fraction for this case. An early, isolated convective storm that formed near the east coast, at the downwind edge of a region of anomalous wet soil, and within the dense cluster of CaPE mesoscale observation stations, is correctly simulated only by TKE-PLACE. It does not develop in any of the other seven runs. A factor separation analysis shows that a successful simulation requires the inclusion of the more sophisticated land surface model, realistic initial soil moisture and temperature, and the higher-order closure of the planetary boundary layer (PBL) in order to better represent the effect of joint and synergistic (nonlinear) contributions from the land surface and PBL on the moist convection. C1 NASA, Goddard Space Flight Ctr, Mesoscale Atmospher Proc Branch, Greenbelt, MD 20771 USA. Columbia Univ, Ctr Climate Syst Res, New York, NY USA. Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Tel Aviv Univ, Dept Geophys & Planetary Sci, IL-69978 Tel Aviv, Israel. Univ Space Res Assoc, Mesoscale Atmospher Proc Branch, Greenbelt, MD USA. Meteo France, CNRM, Toulouse, France. Sci Syst & Applicat Inc, Mesoscale Atmospher Proc Branch, Greenbelt, MD USA. RP Wetzel, PJ (reprint author), NASA, Goddard Space Flight Ctr, Mesoscale Atmospher Proc Branch, Code 912, Greenbelt, MD 20771 USA. RI Munoz, Ricardo/A-1967-2011 NR 39 TC 18 Z9 19 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 6 BP 1441 EP 1461 DI 10.1175/1520-0493(2001)129<1441:ISOFSC>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 434FT UT WOS:000168805000008 ER PT J AU Spencer, RW Braswell, WD AF Spencer, RW Braswell, WD TI Atlantic tropical cyclone monitoring with AMSU-A: Estimation of maximum sustained wind speeds SO MONTHLY WEATHER REVIEW LA English DT Article ID SATELLITE MICROWAVE DATA; RADIOMETER AB The first Advanced Microwave Sounding Unit temperature sounder (AMSU-A) was launched on the NOAA-15 satellite on 13 May 1998. The AMSU-A's higher spatial and radiometric resolutions provide more useful information on the strength of the middle- and upper-tropospheric warm cores associated with tropical cyclones than have previous microwave temperature sounders. The gradient wind relationship suggests that the temperature gradient near the core of tropical cyclones increases nonlinearly with wind speed. The gradient wind equation is recast to include AMSU-A-derived variables. Stepwise regression is used to determine which of these variables is most closely related to maximum sustained winds (Vmax). The satellite variables investigated include the radially averaged gradients at two spatial resolutions of AMSU-A channels 1-10 T-b data (delta T-r(b)), the squares of these gradients, a channel-15-based scattering index (SI89), and area-averaged T-b. Calculations of T-b and delta T-r(b) from mesoscale model simulations of Andrew (1992) reveal the effects of the AMSU spatial sampling on the cyclone warm core presentation. Stepwise regression of 66 AMSU-A terms against National Hurricane Center V-max estimates from the 1998 and 1999 Atlantic hurricane season confirms the existence of a nonlinear relationship between wind speed and radially averaged temperature gradients near the cyclone warm core. Of six regression terms, four are dominated by temperature information, and two are interpreted as correcting for hydrometeor contamination. Jackknifed regressions were performed to estimate the algorithm performance on independent data. For the 82 cases that had in situ measurements of V-max, the average error standard deviation was 4.7 m s(-1). For 108 cases without in situ wind data, the average error standard deviation was 7.5 m s(-1). Operational considerations, including the detection of weak cyclones and false alarm reduction, are also discussed. C1 NASA, George C Marshall Space Flight Ctr, Global Hydrol & Climate Ctr, Huntsville, AL 35805 USA. Comp Sci Corp, Global Hydrol & Climate Ctr, Huntsville, AL USA. RP NASA, George C Marshall Space Flight Ctr, Global Hydrol & Climate Ctr, 320 Sparkman Dr, Huntsville, AL 35805 USA. EM Roy.Spencer@msfc.nasa.gov NR 25 TC 20 Z9 24 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 6 BP 1518 EP 1532 DI 10.1175/1520-0493(2001)129<1518:ATCMWA>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 434FT UT WOS:000168805000012 ER PT J AU Druyan, LM Fulakeza, M Lonergan, P Saloum, M AF Druyan, LM Fulakeza, M Lonergan, P Saloum, M TI A regional model study of synoptic features over West Africa SO MONTHLY WEATHER REVIEW LA English DT Article ID WAVE DISTURBANCES; CLIMATE MODEL; SURFACE-TEMPERATURE; EASTERN AFRICA; SHORT RAINS; PARAMETERIZATION; SIMULATIONS; CONVECTION; MOISTURE AB Synoptic weather features over West Africa were studied in simulations by the regional simulation model (RM) at the NASA Goddard Institute for Space Studies. These pioneering simulations represent the beginning of an effort to adapt regional models for weather and climate prediction over West Africa. The RM uses a Cartesian grid with 50-km horizontal resolution and 15 vertical levels. An ensemble of four simulations was forced with lateral boundary conditions from ECMWF global analyses for the period 8-22 August 1988. The simulated midtropospheric circulation includes the skillful development and movement of several African wave disturbances. Wavelet analysis of midtropospheric winds detected a dominant periodicity of about 4 days and a secondary periodicity of 5-8 days. Spatial distributions of RM precipitation and precipitation time series were validated against daily rain gauge measurements and International Satellite Cloud Climatology Project satellite infrared cloud imagery. The time-space distribution of simulated precipitation was made more realistic by combining the ECMWF initial conditions with a 24-h spinup of the moisture field and also by damping high-frequency gravity waves by dynamic initialization. Model precipitation "forecasts'' over the central Sahel were correlated with observations for about 3 days, but reinitializing with observed data on day 5 resulted in a dramatic improvement in the precipitation validation over the remaining 9 days. Results imply that information via the lateral boundary conditions is not always sufficient to minimize departures between simulated and actual precipitation patterns for more than several days. In addition, there was some evidence that the new initialization may increase the simulations' sensitivity to the quality of lateral boundary conditions. C1 NASA, Goddard Inst Space Studies, Columbia Univ, Ctr Climate Syst Res, New York, NY 10025 USA. NASA, Goddard Inst Space Studies, Sci Syst & Applicat Inc, New York, NY 10025 USA. Direct Meteorol Natl, Niamey, Niger. RP Druyan, LM (reprint author), NASA, Goddard Inst Space Studies, Columbia Univ, Ctr Climate Syst Res, 2880 Broadway, New York, NY 10025 USA. NR 27 TC 15 Z9 16 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 6 BP 1564 EP 1577 DI 10.1175/1520-0493(2001)129<1564:ARMSOS>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 434FT UT WOS:000168805000015 ER PT J AU Chang, DE Weinman, JA Morales, CA Olson, WS AF Chang, DE Weinman, JA Morales, CA Olson, WS TI The effect of spaceborne microwave and ground-based continuous lightning measurements on forecasts of the 1998 Groundhog Day storm SO MONTHLY WEATHER REVIEW LA English DT Article ID MESOSCALE MODEL; PRECIPITATION; SCHEME; CYCLONE; REFLECTIVITY; ASSIMILATION; RATES AB This study seeks to evaluate the impact of several newly available sources of meteorological data on mesoscale model forecasts of the extratropical cyclone that struck Florida on 2 February 1998. Intermittent measurements of precipitation and integrated water vapor (IWV) distributions were obtained from Special Sensor Microwave/Imager (SSM/I) and Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) observations. The TMI also provided sea surface temperatures (SSTs) with structural detail of the Loop Current and Gulf Stream. Continuous lightning distributions were measured with a network of very low frequency radio receivers. Lightning data were tuned with intermittent spaceborne microwave radiometer data through a probability matching technique to continuously estimate convective rainfall rates. A series of experiments were undertaken to evaluate the effect of those data on mesoscale model forecasts produced after assimilating processed rainfall and IWV for 6 h. Assimilating processed rainfall, IWV, and SSTs from TMI measurements in the model yielded improved forecasts of precipitation distributions and vertical motion fields. Assimilating those data also produced an improved 9-h forecast of the radar reflectivity cross section that was validated with a coincident observation from the TRMM spaceborne precipitation radar. Sensitivity experiments showed that processed rainfall information had greater impact on the rainfall forecast than IWV and SST information. Assimilating latent heating in the correct location of the forecast model was found to be more important than an accurate determination of the rainfall intensity. C1 NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Microwave Sensors Branch, Greenbelt, MD 20771 USA. Univ Connecticut, Dept Civil Engn, Storrs, CT 06269 USA. CNPq, Brasilia, DF, Brazil. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. RP Chang, DE (reprint author), NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Code 975, Greenbelt, MD 20771 USA. NR 45 TC 34 Z9 40 U1 1 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 8 BP 1809 EP 1833 DI 10.1175/1520-0493(2001)129<1809:TEOSMA>2.0.CO;2 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 454XF UT WOS:000169996500003 ER PT J AU Pu, ZX Braun, SA AF Pu, ZX Braun, SA TI Evaluation of bogus vortex techniques with four-dimensional variational data assimilation SO MONTHLY WEATHER REVIEW LA English DT Article ID MODEL; INITIALIZATION; PREDICTION; SIMULATION; CYCLONE; SCHEME; TRACK; TESTS AB The effectiveness of a four-dimensional variational data assimilation (4DVAR) technique for creating "bogus" vortices in numerical simulations of hurricanes is evaluated in this study. A series of numerical experiments is conducted to generate initial vortices for Hurricane Georges and Bonnie (1998) in the Atlantic Ocean by assimilating bogus sea level pressure and wind information into a mesoscale numerical model (MM5). Several different strategies are tested for investigating the sensitivity of the initial vortex representation to the type of bogus information. While some of the results in this study confirm conclusions made in previous studies, some significant differences are obtained regarding the role of bogus wind data in creating a realistic bogus vortex. In contrast with previous studies in which the bogus wind data had only a marginal impact on creating a realistic hurricane, this study concludes that the wind information is very important because 1) with assimilation of only bogus sea level pressure information, the response in wind field is contained largely within the divergent component, with strong low-level convergence leading to strong upward motion near the center; and 2) with assimilation of bogus wind data only, an expected dominance of the rotational component of the wind field is generated. In this latter case, the minimum pressure is also adjusted significantly, although the adjusted sea level pressure does not always match the actual hurricane minimum pressure. The generated vortex offers a smooth start to the forecast and leads to a significant improvement in the forecast. Only when both the bogus sea level pressure and wind information are assimilated together does the model produce a vortex that represents the actual intensity of the hurricane and results in significant improvements to forecasts of both hurricane intensity and track. As the 4DVAR experiments are performed with relatively coarse horizontal grid resolution in this study, the impact of vortex size on the structure of the initial vortex is also evaluated. The authors find that when the scale of the specified bogus vortex is smaller than that which can be resolved by the model, the assimilation method may result in structures that do not completely resemble observed structures in hurricanes. In contrast, when the vortex is sufficiently large for it to be resolved on the horizontal grid, but not so large as to be unrealistic, more reasonable hurricane structures are obtained. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. RP Pu, ZX (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 912, Greenbelt, MD 20771 USA. NR 20 TC 70 Z9 78 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 8 BP 2023 EP 2039 DI 10.1175/1520-0493(2001)129<2023:EOBVTW>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 454XF UT WOS:000169996500013 ER PT J AU Krishnamurti, TN Surendran, S Shin, DW Correa-Torres, RJ Kumar, TSVV Williford, E Kummerow, C Adler, RF Simpson, J Kakar, R Olson, WS Turk, FJ AF Krishnamurti, TN Surendran, S Shin, DW Correa-Torres, RJ Kumar, TSVV Williford, E Kummerow, C Adler, RF Simpson, J Kakar, R Olson, WS Turk, FJ TI Real-time multianalysis-multimodel superensemble forecasts of precipitation using TRMM and SSM/I products SO MONTHLY WEATHER REVIEW LA English DT Article ID VARIATIONAL DATA ASSIMILATION; NUMERICAL WEATHER PREDICTION; PHYSICAL INITIALIZATION; RETRIEVAL ALGORITHMS; DIABATIC INITIALIZATION; SEASONAL CLIMATE; RAINFALL; MODEL; MICROWAVE; TROPICS AB This paper addresses real-time precipitation forecasts from a multianalysis-multimodel superensemble. The methodology for the construction of the superensemble forecasts follows previous recent publications on this topic. This study includes forecasts from multimodels of a number of global operational centers. A multianalysis component based on the Florida State University (FSU) global spectral model that utilizes TRMM and SSM/I datasets and a number of rain-rate algorithms is also included. The difference in the analysis arises from the use of these rain rates within physical initialization that produces distinct differences among these components in the divergence, heating, moisture, and rain-rate descriptions. A total of 11 models, of which 5 represent global operational models and 6 represent multianalysis forecasts from the FSU model initialized by different rain-rate algorithms, are included in the multianalysis-multimodel system studied here. In this paper, "multimodel'' refers to different models whose forecasts are being assimilated for the construction of the superensemble. "Multianalysis'' refers to different initial analysis contributing to forecasts from the same model. The term superensemble is being used here to denote the bias-corrected forecasts based on the products derived from the multimodel and the multianalysis. The training period is covered by nearly 120 forecast experiments prior to 1 January 2000 for each of the multimodels. These are all 3-day forecasts. The statistical bias of the models is determined from multiple linear regression of these forecasts against a "best'' rainfall analysis field that is based on TRMM and SSM/I datasets and using the rain-rate algorithms recently developed at NASA Goddard Space Flight Center. This paper discusses the results of real-time rainfall forecasts based on this system. The main results of this study are that the multianalysis-multimodel superensemble has a much higher skill than the participating member models. The skill of this system is higher than those of the ensemble mean that assigns a weight of 1.0 to all including the poorer models and the ensemble mean of bias-removed individual models. The selective weights for the entire multianalysis-multimodel superensemble forecast system make it superior to individual models and the above mean representations. The skill of precipitation forecasts is addressed in several ways. The skill of the superensemble-based rain rates is shown to be higher than the following: (a) individual model's skills with and without physical initialization, (b) skill of the ensemble mean, and (c) skill of the ensemble mean of individually bias-removed models. The equitable-threat scores at many thresholds of rain are also examined for the various models and noted that for days 1-3 of forecasts, the superensemble-based forecasts do have the highest skills. The training phase is a major component of the superensemble. Issues on optimizing the number of training days is addressed by examining training with days of high forecast skill versus training with low forecast skill, and training with the best available rain-rate datasets versus those from poor representations of rain. Finally the usefulness of superensemble forecasts of rain for providing possible guidance for flood events such as the one over Mozambique during February 2000 is shown. C1 Florida State Univ, Dept Meteorol, Tallahassee, FL 32306 USA. Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA Headquarters, Washington, DC USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. USN, Res Lab, Marine Meteorol Div, Monterey, CA USA. RP Krishnamurti, TN (reprint author), Florida State Univ, Dept Meteorol, Tallahassee, FL 32306 USA. RI Tallapragada, Vijaya Kumar/A-2421-2008; Surendran, Sajani/C-3339-2009 NR 45 TC 75 Z9 83 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PY 2001 VL 129 IS 12 BP 2861 EP 2883 DI 10.1175/1520-0493(2001)129<2861:RTMMSF>2.0.CO;2 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 490HG UT WOS:000172045700002 ER PT S AU Jorgensen, K Africano, J Stansbery, G Kervin, P Hamada, K Sydney, P AF Jorgensen, K Africano, J Stansbery, G Kervin, P Hamada, K Sydney, P BE Pirich, AR Repak, PL Idell, PS Czyzak, SR TI Determining the material type of man-made orbiting objects using low resolution reflectance spectroscopy SO MULTIFREQUENCY ELECTRONIC/PHOTONIC DEVICES AND SYSTEMS FOR DUAL-USE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Multifrequency Electronic/Photonic Devices and Systems for Dual-Use Applications CY JUL 29-30, 2001 CL SAN DIEGO, CA SP SPIE DE orbital debris; reflectance spectroscopy; material type AB The purpose of this research is to improve the knowledge of the physical properties of orbital debris., specifically the material type. Combining the use of the fast-tracking United States Air Force Research Laboratory (AFRL) telescopes with a common astronomical technique, spectroscopy, and NASA resources was a natural step toward determining the material type of orbiting objects remotely. Currently operating at the AFRL Maui Optical Site (AMOS) is a 1.6-meter telescope designed to track fast moving objects like those found in lower Earth orbit (LEO). Using the spectral range of 0.4 - 0.9 microns (4000 - 9000 angstroms), researchers can separate materials into classification ranges. Within the above range, aluminum, paints, plastics, and other metals have different absorption features as well as slopes in their respective spectra. The spectrograph used on this telescope yields a three-angstrom resolution; large enough to see smaller features mentioned and thus determine the material type of the object. The results of the NASA AMOS Spectral Study (NASS) are presented herein. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Jorgensen, K (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code C104, Houston, TX 77058 USA. NR 3 TC 2 Z9 4 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4204-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4490 BP 237 EP 244 DI 10.1117/12.455430 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT90T UT WOS:000174396400026 ER PT S AU Maley, PD Palmer, JL AF Maley, PD Palmer, JL BE Pirich, AR Repak, PL Idell, PS Czyzak, SR TI Proton ullage motor observations as possible precursors to explosions in space SO MULTIFREQUENCY ELECTRONIC/PHOTONIC DEVICES AND SYSTEMS FOR DUAL-USE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Multifrequency Electronic/Photonic Devices and Systems for Dual-Use Applications CY JUL 29-30, 2001 CL SAN DIEGO, CA SP SPIE DE space debris; ullage motors; explosions; optical observations; satellite tracking AB Two optical observation campaigns during 1999 and 2000 were conducted to monitor the optical characteristics of the Proton 4 tillage motor population located in mainly geostationary transfer orbits about the earth. This study attempted to physically characterize the intact ullage motors and those that have exploded in space using conventional large aperture binocular optics and 3rd generation image intensified video (commonly employed for non-military astronomical observation) in order to determine if optical signatures could reveal evidence as to which motors might be candidates for explosion. We find that some motors do not spin down through normally expected damping; explosions do not consistently result in the catastrophic destruction of the parent body involved; accelerations in the rotation rates of some intact tillage motors have open discovered; some fragmentations do not result in an increase in rotation of the surviving parent as might be expected. No conclusive evidence was obtained that could lead to positively identifying precursors for future explosion. Yet, through statistical methodology we determined that there is a strong probability of additional explosions until the majority of motors launched between 1982 and 1996 decay from orbit. We estimate the probability of at least one of 46 tillage motors currently in orbit exploding before decay is greater than 0.9999. The threat of explosions is not expected to be mitigated by natural decay of all candidate exploders for at least 50 years. C1 NASA, Lyndon B Johnson Space Ctr, Astron Soc, Houston, TX 77058 USA. RP Maley, PD (reprint author), 4535 Cedar Ridge Trail, Houston, TX 77059 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4204-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4490 BP 307 EP 318 DI 10.1117/12.455439 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT90T UT WOS:000174396400034 ER PT B AU Wildermuth, S Teodorovic, N Hilfiker, PR Marincek, B AF Wildermuth, S Teodorovic, N Hilfiker, PR Marincek, B BE Marincek, B Ros, PR Reiser, M Baker, ME TI Three-dimensional imaging and virtual reality applications of multi slice computed tomography SO MULTISLICE CT: A PRACTICAL GUIDE LA English DT Proceedings Paper CT 5th International SOMATOM CT Scientific User Conference CY JUN, 2000 CL ZURICH, SWITZERLAND SP Univ Hosp Zurich, Klinikum Grosshardern, Brigham & Womens Hosp, Boston, Cleveland Clin Fdn ID ACETABULAR FRACTURES; CT COLONOGRAPHY; HELICAL CT; COLORECTAL-CANCER; MR COLONOGRAPHY; DISPLAY MODES; SPIRAL CT; 3D CT; ENDOSCOPY; DIAGNOSIS C1 NASA, Ames Res Ctr, Ctr Bioinformat, Moffett Field, CA 94035 USA. RP Wildermuth, S (reprint author), NASA, Ames Res Ctr, Ctr Bioinformat, Moffett Field, CA 94035 USA. NR 38 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-41116-X PY 2001 BP 37 EP 56 PG 20 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA BR70Z UT WOS:000167244900005 ER PT S AU Arepalli, S Nikolaev, P Holmes, W Hadjiev, V Files, B AF Arepalli, S Nikolaev, P Holmes, W Hadjiev, V Files, B BE Saito, S Ando, T Iwasa, Y Kikuchi, K Kobayashi, M Saito, Y TI Production and measurements of isolated single-wall carbon nanotubes SO NANONETWORK MATERIALS: FULLERENES, NANOTUBES AND RELATED SYSTEMS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT International Symposium on Nanonetwork Materials, Fullerenes, Nanotubes, and Related Systems CY JAN 15-18, 2001 CL KAMAKURA, JAPAN AB The production of isolated single wall carbon nanotubes (SWNTs) is accomplished using the laser oven process. Material is collected on quartz substrates at different locations in the laser oven for a variety of flow conditions. The lengths and diameter distributions of the nanotubes are measured directly (without additional processing steps) using AFM. Preliminary Raman data taken using 2D scans indicate the feasibility of this technique for length and diameter determination. The AFM study indicated the formation of long individual nanotubes, which then seem to coalesce into bigger bundles. The role of the inner tube of the flow-tube set up is confirmed to improve interactions between SWNTs resulting in formation of bundles, Flowing buffer gas seems to influence the dispersion of particulate material in the nanotube product. C1 NASA, Lyndon B Johnson Space Ctr, GB Tech, Houston, TX 77058 USA. RP Arepalli, S (reprint author), NASA, Lyndon B Johnson Space Ctr, GB Tech, 2101 NASA Rd 1, Houston, TX 77058 USA. RI Hadjiev, Viktor/A-7069-2008 OI Hadjiev, Viktor/0000-0001-8579-9357 NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0032-6 J9 AIP CONF PROC PY 2001 VL 590 BP 11 EP 14 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BU49U UT WOS:000176150700003 ER PT J AU Ming, DW Boettinger, JL AF Ming, DW Boettinger, JL TI Zeolites in soil environments SO NATURAL ZEOLITES: OCCURRENCE, PROPERTIES, APPLICATIONS SE REVIEWS IN MINERALOGY & GEOCHEMISTRY LA English DT Review ID SAN-GABRIEL MOUNTAINS; WESTERN-GHATS; CALIFORNIA; CLINOPTILOLITE; MINERALOGY; ALFISOLS; GENESIS; ORIGIN; DESERT; INDIA C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Utah State Univ, Dept Plant Soils & Biometeorol, Logan, UT 84322 USA. RP Ming, DW (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code SN2, Houston, TX 77058 USA. NR 82 TC 18 Z9 19 U1 1 U2 6 PU MINERALOGICAL SOC AMERICA PI WASHINGTON PA 1015 EIGHTEENTH ST, NW, SUITE 601, WASHINGTON, DC 20036-5274 USA SN 1529-6466 J9 REV MINERAL GEOCHEM PY 2001 VL 45 BP 323 EP 345 DI 10.2138/rmg.2001.45.11 PG 23 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA BU62E UT WOS:000176544500011 ER PT J AU Ming, DW Allen, ER AF Ming, DW Allen, ER TI Use of natural zeolites in agronomy, horticulture, and environmental soil remediation SO NATURAL ZEOLITES: OCCURRENCE, PROPERTIES, APPLICATIONS SE REVIEWS IN MINERALOGY & GEOCHEMISTRY LA English DT Review ID AMMONIUM-LOADED CLINOPTILOLITE; SLOW-RELEASE FERTILIZER; PHOSPHATE ROCK SYSTEMS; NITROGEN-FERTILIZER; SYNTHETIC ZEOLITES; ION-EXCHANGE; PHOSPHORUS; AMENDMENTS; PHILLIPSITE; POTASSIUM C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Zeopon Gardens, Mason City, IL 62664 USA. RP Ming, DW (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code SX, Houston, TX 77058 USA. NR 122 TC 46 Z9 49 U1 5 U2 20 PU MINERALOGICAL SOC AMERICA PI WASHINGTON PA 1015 EIGHTEENTH ST, NW, SUITE 601, WASHINGTON, DC 20036-5274 USA SN 1529-6466 J9 REV MINERAL GEOCHEM PY 2001 VL 45 BP 619 EP 654 DI 10.2138/rmg.2001.45.18 PG 36 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA BU62E UT WOS:000176544500018 ER PT B AU Thompson, DJ AF Thompson, DJ BE Carraminana, A Reimer, O Thompson, DJ TI Unidentified gamma-ray sources: An introduction SO NATURE OF UNIDENTIFIED GALACTIC HIGH-ENERGY GAMMA-RAY SOURCES SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT Workshop on the Nature of Unidentified Galactic High-Energy Gamma-Ray Sources CY OCT 09-11, 2000 CL INST NACL ASTROFIS, OPT & ELECTR, TONANTZINTLA, MEXICO SP Consejo Nacl Ciencia & Technol HO INST NACL ASTROFIS, OPT & ELECTR DE gamma-ray sources; unidentified ID X-RAY; COS-B; EGRET SOURCES; RADIATION; EMISSION; PULSARS; PULSATIONS; CYGNUS-X-3; SATELLITE; DISCOVERY AB What makes a gamma-ray source "unidentified"? Typical gamma-ray source error boxes are large by astronomical standards; therefore a positional correlation with a known object is usually not enough to identify a source. Historically, identifications have come in several ways: (1) finding a time-variable signal seen at another wavelength; (2) repeatedly seeing within gamma-ray error boxes members of a small, well-defined class of energetic sources; (3) seeing spatially-resolved gamma-ray emission from an extended source; and (4) finding a positionally-correlated, highly-unusual object with special parameters that might be expected to produce gamma rays. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Thompson, DJ (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RI Thompson, David/D-2939-2012; Reimer, Olaf/A-3117-2013 OI Thompson, David/0000-0001-5217-9135; Reimer, Olaf/0000-0001-6953-1385 NR 43 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0010-3 J9 ASTROPHYS SPACE SC L PY 2001 VL 267 BP 3 EP 16 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BT52H UT WOS:000173242800001 ER PT B AU Reimer, O AF Reimer, O BE Carraminana, A Reimer, O Thompson, DJ TI The gamma-ray properties of unidentified EGRET sources SO NATURE OF UNIDENTIFIED GALACTIC HIGH-ENERGY GAMMA-RAY SOURCES SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT Workshop on the Nature of Unidentified Galactic High-Energy Gamma-Ray Sources CY OCT 09-11, 2000 CL INST NACL ASTROFIS, OPT & ELECTR, TONANTZINTLA, MEXICO SP Consejo Nacl Ciencia & Technol HO INST NACL ASTROFIS, OPT & ELECTR DE high-energy gamma-ray sources; unidentified EGRET sources; population studies ID GALACTIC PLANE; VARIABILITY; EMISSION AB Although the majority of gamma-ray sources still remain unidentified, we have various kinds of information to characterize the observational properties of unidentified EGRET sources. Despite astronomical properties like locations of individual sources or the collective arrangement of the class as such, the nine years of CGRO observations provide the ability to investigate flux variability at different timescales, enable us to perform periodicity searches, determine gamma-ray source spectra between 30 MeV and 10 GeV and even investigate spectral variability. The basic observational properties of unidentified high-energy gamma-ray sources discovered by EGRET are reviewed. Various instrumental and observational peculiarities affecting the interpretation of the EGRET data are pointed out, also describing the way such biases might affect scientific conclusions drawn from the EGRET data. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Reimer, O (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RI Thompson, David/D-2939-2012; Reimer, Olaf/A-3117-2013 OI Thompson, David/0000-0001-5217-9135; Reimer, Olaf/0000-0001-6953-1385 NR 20 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0010-3 J9 ASTROPHYS SPACE SC L PY 2001 VL 267 BP 17 EP 34 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BT52H UT WOS:000173242800002 ER PT B AU Gehrels, N Macomb, DJ Bertsch, DL Thompson, DJ Hartman, RC Mattson, BJ AF Gehrels, N Macomb, DJ Bertsch, DL Thompson, DJ Hartman, RC Mattson, BJ BE Carraminana, A Reimer, O Thompson, DJ TI Population studies of unidentified high-energy gamma-ray sources SO NATURE OF UNIDENTIFIED GALACTIC HIGH-ENERGY GAMMA-RAY SOURCES SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT Workshop on the Nature of Unidentified Galactic High-Energy Gamma-Ray Sources CY OCT 09-11, 2000 CL INST NACL ASTROFIS, OPT & ELECTR, TONANTZINTLA, MEXICO SP Consejo Nacl Ciencia & Technol HO INST NACL ASTROFIS, OPT & ELECTR DE gamma-ray : observations; gamma-ray sources : unidentified ID SUPERNOVA-REMNANTS; EGRET OBSERVATIONS; GOULDS BELT; DISCOVERY; EMISSION; PULSARS; GAS AB The third EGRET catalog contains similar to 170 unidentified high energy gamma-ray point sources. Here we report that this group contains two populations with different spatial distributions, flux distributions and spectral properties. A cluster of similar to 20 sources lies just north of the Galactic Center and is part of a larger population of faint objects at mid-latitudes. We show that these mid-latitude sources are distinct from the population of bright sources found at lower latitudes. The spatial distribution of the mid-latitude population suggests a Gould belt origin. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gehrels, N (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 661, Greenbelt, MD 20771 USA. RI Thompson, David/D-2939-2012; Reimer, Olaf/A-3117-2013 OI Thompson, David/0000-0001-5217-9135; Reimer, Olaf/0000-0001-6953-1385 NR 20 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0010-3 J9 ASTROPHYS SPACE SC L PY 2001 VL 267 BP 81 EP 88 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BT52H UT WOS:000173242800006 ER PT B AU Digel, SW AF Digel, SW BE Carraminana, A Reimer, O Thompson, DJ TI Diffuse sources of high-energy gamma rays in the Milky Way SO NATURE OF UNIDENTIFIED GALACTIC HIGH-ENERGY GAMMA-RAY SOURCES SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT Workshop on the Nature of Unidentified Galactic High-Energy Gamma-Ray Sources CY OCT 09-11, 2000 CL INST NACL ASTROFIS, OPT & ELECTR, TONANTZINTLA, MEXICO SP Consejo Nacl Ciencia & Technol HO INST NACL ASTROFIS, OPT & ELECTR DE Milky Way galaxy; gamma rays; cosmic rays ID DARK-MATTER; EGRET OBSERVATIONS; MOLECULAR CLOUDS; GALACTIC PLANE; COSMIC-RAYS; EMISSION; GALAXY; CONSTRAINTS; RADIATION; SPECTRUM AB Cosmic-ray interactions with interstellar gas and low-energy photons make the Milky Way galaxy a gamma-ray source that spans the whole sky. The low instrumental background, large effective area, good angular resolution, and long mission life of the Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory provided the first opportunity for comprehensive study of this diffuse gamma-ray emission. I will discuss what has been learned from EGRET about the cosmic rays and interstellar gas in the Milky Way, including the apparent excess of GeV emission from the interstellar medium, the potential Galactic halo at GeV energies, and the implications of EGRET observations for the nature of dark matter in the Milky Way. For many gamma-ray astronomers, the emission of the Milky Way is primarily a background to be removed in the study of point sources. I will illustrate the potential for diffuse emission to confuse or contaminate the EGRET source catalogs, and conclude with the prospects for advances with the Gamma-ray Large Area Space Telescope (GLAST). C1 NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Greenbelt, MD 20771 USA. RP Digel, SW (reprint author), NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Code 661, Greenbelt, MD 20771 USA. RI Thompson, David/D-2939-2012; Reimer, Olaf/A-3117-2013 OI Thompson, David/0000-0001-5217-9135; Reimer, Olaf/0000-0001-6953-1385 NR 34 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0010-3 J9 ASTROPHYS SPACE SC L PY 2001 VL 267 BP 197 EP 211 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BT52H UT WOS:000173242800014 ER PT B AU Gehrels, N AF Gehrels, N CA GLAST Sci Team BE Carraminana, A Reimer, O Thompson, DJ TI Gamma ray astronomy in the era of GLAST SO NATURE OF UNIDENTIFIED GALACTIC HIGH-ENERGY GAMMA-RAY SOURCES SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT Workshop on the Nature of Unidentified Galactic High-Energy Gamma-Ray Sources CY OCT 09-11, 2000 CL INST NACL ASTROFIS, OPT & ELECTR, TONANTZINTLA, MEXICO SP Consejo Nacl Ciencia & Technol HO INST NACL ASTROFIS, OPT & ELECTR DE gamma-ray astronomy; space astrophysics; future missions ID HIGH-ENERGY; DISCOVERY AB The Gamma Ray Large Area Space Telescope (GLAST) is a high energy (20 MeV to 300 GeV) gamma-ray astronomy mission scheduled for launch in 2005. The underlying theme of the GLAST mission is to explore sites of particle acceleration in the universe. GLAST will build on discoveries made by EGRET/CGRO, examining blazars, gamma-ray bursts, supernova remnants, pulsars, dark matter and solar flares. In addition, GLAST observations may begin to uncover the mystery of the similar to 170 unidentified high-energy gamma-ray. The sensitivity will be G 6 x 10(-9) cm(-2) s(-1) for a one year survey at high galactic latitude, a factor of similar to 15 better than EGRET. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gehrels, N (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. RI Thompson, David/D-2939-2012; Reimer, Olaf/A-3117-2013 OI Thompson, David/0000-0001-5217-9135; Reimer, Olaf/0000-0001-6953-1385 NR 6 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0010-3 J9 ASTROPHYS SPACE SC L PY 2001 VL 267 BP 321 EP 330 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BT52H UT WOS:000173242800023 ER PT B AU Thompson, DJ AF Thompson, DJ BE Carraminana, A Reimer, O Thompson, DJ TI Unidentified gamma-ray sources: Summary and conclusion SO NATURE OF UNIDENTIFIED GALACTIC HIGH-ENERGY GAMMA-RAY SOURCES SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT Workshop on the Nature of Unidentified Galactic High-Energy Gamma-Ray Sources CY OCT 09-11, 2000 CL INST NACL ASTROFIS, OPT & ELECTR, TONANTZINTLA, MEXICO SP Consejo Nacl Ciencia & Technol HO INST NACL ASTROFIS, OPT & ELECTR DE gamma-ray sources; unidentified AB As the era of the Compton Gamma Ray Observatory draws to a close, the problem of the unidentified Galactic sources remains one of the great unsolved mysteries. Participants in this meeting have made substantial progress in defining the problem, suggesting possible candidate objects, and anticipating the future steps that will lead to a resolution. C1 NASA, Goddard Space Flight Ctr, High Energy Phys Lab, Greenbelt, MD 20771 USA. RP Thompson, DJ (reprint author), NASA, Goddard Space Flight Ctr, High Energy Phys Lab, Greenbelt, MD 20771 USA. RI Thompson, David/D-2939-2012; Reimer, Olaf/A-3117-2013 OI Thompson, David/0000-0001-5217-9135; Reimer, Olaf/0000-0001-6953-1385 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0010-3 J9 ASTROPHYS SPACE SC L PY 2001 VL 267 BP 349 EP 352 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BT52H UT WOS:000173242800026 ER PT S AU Coradini, A Campbell, J De Sanctis, MC Di Pippo, S Espinasse, S Flamini, E Mugnuolo, R Orosei, R Piccioni, G AF Coradini, A Campbell, J De Sanctis, MC Di Pippo, S Espinasse, S Flamini, E Mugnuolo, R Orosei, R Piccioni, G BE Ip, WH Masson, PL TI Italian participation in the Mars exploration program SO NEAR-EARTH OBJECTS, IMPACT HAZARDS, AND THE MARS INTERNATIONAL PROGRAM SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT B0 3/B0 4-C3 5 Symposium of COSPAR Scientific Commission B held at the 33rd COSPAR Scientific Assembly CY JUL 16-23, 2000 CL WARSAW, POLAND SP Beijing Astron Observat, Chinese Natl Astron Observat, Int Astron Union, Comm Space Res, Ctr Natl Etud Spatiales, Inst Space & Astron Sci AB Recently agreements have been signed between the Italian Space Agency (ASI) and ESA and NASA for the exploration of Mars. These agreements initiate the participation of the Italian scientific community as well as the Italian industrial community in the international program to explore Mars. ASI and NASA have agreed to co-operate in a long-term systematic program of robotic exploration of Mars sustained by a series of missions to Mars in support of their respective strategic goals. The Mars Surveyor Program is a sustained series of missions to Mars, each of which will provide important focused scientific results, ASI is expecting to participate in the future missions with the provision of two sub-systems: a subsurface drill and a scientific package. The drill will be capable of drilling and collecting several samples and delivering them to instruments located within a scientific package fixed on a landed platform. ASI is also providing scientific instruments placed on a scientific package (IPSE) fixed with on the lander platform. The goals of the investigations are to study physical and mineralogical properties of bulk soil and dust (atmospheric and surface) as well as geochemical, structural, radiation and geophysical properties of subsurface materials to a depth of 0.5 meters. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 ARTOV, CNR, Ist Astrofis Spaziale, I-00133 Rome, Italy. Jet Prop Lab, Pasadena, CA 91109 USA. Agenzia Spaziale Italiana, I-00161 Rome, Italy. RP Coradini, A (reprint author), ARTOV, CNR, Ist Astrofis Spaziale, Via Fosso Cavaliere, I-00133 Rome, Italy. RI De Sanctis, Maria Cristina/G-5232-2013; OI De Sanctis, Maria Cristina/0000-0002-3463-4437; Piccioni, Giuseppe/0000-0002-7893-6808 NR 1 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 28 IS 8 BP 1197 EP 1202 DI 10.1016/S0273-1177(01)00278-2 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT68E UT WOS:000173723500012 ER PT S AU Barriot, JP Dehant V Folkner, W Cerisier, JC Ribes, A Benoist, J Van Hoolst, T Defraigne, P Warnant, R Preston, RA Romans, L Wu, S Wernik, AW AF Barriot, JP Dehant, V Folkner, W Cerisier, JC Ribes, A Benoist, J Van Hoolst, T Defraigne, P Warnant, R Preston, RA Romans, L Wu, S Wernik, AW BE Ip, WH Masson, PL TI The NEtlander Ionosphere and Geodesy Experiment SO NEAR-EARTH OBJECTS, IMPACT HAZARDS, AND THE MARS INTERNATIONAL PROGRAM SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT B0 3/B0 4-C3 5 Symposium of COSPAR Scientific Commission B held at the 33rd COSPAR Scientific Assembly CY JUL 16-23, 2000 CL WARSAW, POLAND SP Beijing Astron Observ, Chinese Natl Astron Observ, Int Astron Union, Comm Space Res, Ctr Natl Etud Spatiales, Inst Space & Astron Sci ID MARS GLOBAL SURVEYOR; NIGHTSIDE VENUS IONOSPHERE; SOLAR-WIND INTERACTION; FREE CORE NUTATION; INTERIOR STRUCTURE; MAG/ER EXPERIMENT; CHANDLER-WOBBLE; MAGNETIC-FIELD; PLASMA; FLUCTUATIONS AB The NEtlander Ionosphere and Geodesy Experiment (NEIGE) of the Netlander Mission to Mars has two series of scientific objectives: (1) to determine Mars orientation parameters in order to obtain information about the interior of Mars and about the seasonal mass exchange between atmosphere and ice caps; and (2) to determine the total electron content (TEC) and the scintillation of radio signals in order to study the large- and small-scale structure of the ionosphere of Mars. These two sets CC information will be derived from measurements of amplitudes and Doppler shifts of radio links at UHF and X-band between the Netlander microstations on the Mars surface and an orbiter and between this orbiter and the Earth (at X-band). (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 CNES GRGS, OMP, F-31400 Toulouse, France. Observ Royal Belgique, B-1180 Brussels, Belgium. Jet Prop Lab, Los Angeles, CA USA. Ctr Etud Environm Terrestre & Planetaires, F-94107 St Maur des Fosses, France. Ctr Natl Etud Spatiales, F-31401 Toulouse, France. Polish Acad Sci, Space Res Ctr, PL-00716 Warsaw, Poland. RP Barriot, JP (reprint author), CNES GRGS, OMP, 14 Av E Belin, F-31400 Toulouse, France. NR 37 TC 24 Z9 26 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES-SERIES PY 2001 VL 28 IS 8 BP 1237 EP 1249 DI 10.1016/S0273-1177(01)00295-2 PG 13 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT68E UT WOS:000173723500018 ER PT J AU Rosipal, R Girolami, M Trejo, LJ Cichocki, A AF Rosipal, R Girolami, M Trejo, LJ Cichocki, A TI Kernel PCA for feature extraction and de-noising in nonlinear regression SO NEURAL COMPUTING & APPLICATIONS LA English DT Article DE de-noising; feature extraction; human performance monitoring; kernel functions; nonlinear regression; principal components ID EVENT-RELATED POTENTIALS; PERFORMANCE AB In this paper, we propose the application of the Kernel Principal Component Analysis (PCA) technique for feature selection in a. high-dimensional feature space, where input variables are mapped by a Gaussian kernel. The extracted features are employed in the regression problems of chaotic Mackey-Glass time-series prediction in a noisy environment and estimating human signal detection performance from brain event-related potentials elicited by task relevant signals. We compared results obtained using either Kernel PCA or linear PCA as data preprocessing steps. On the human signal detection task, we report the superiority of Kernel PCA feature extraction over linear PCA. Similar to linear PCA, we demonstrate de-noising of the original data by the appropriate selection of various nonlinear principal components. The theoretical relation and experimental comparison of Kernel Principal Components Regression, Kernel Ridge Regression and epsilon-insensitive Support Vector Regression is also provided. C1 NASA, Ames Res Ctr, Computat Sci Div, Moffett Field, CA 94035 USA. Univ Paisley, Appl Computat Intelligence Res Unit, Sch Informat & Commun Technol, Paisley PA1 2BE, Renfrew, Scotland. RIKEN, Lab Adv Brain Signal Proc, Brain Sci Inst, Wako, Saitama 35101, Japan. Warsaw Univ Technol, Warsaw, Poland. RP Rosipal, R (reprint author), NASA, Ames Res Ctr, Computat Sci Div, Mail Stop 269-3, Moffett Field, CA 94035 USA. RI Cichocki, Andrzej/A-1545-2015; Rosipal, Roman/B-8060-2008 OI Cichocki, Andrzej/0000-0002-8364-7226; NR 26 TC 81 Z9 91 U1 2 U2 24 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0941-0643 J9 NEURAL COMPUT APPL JI Neural Comput. Appl. PY 2001 VL 10 IS 3 BP 231 EP 243 DI 10.1007/s521-001-8051-z PG 13 WC Computer Science, Artificial Intelligence SC Computer Science GA 522VB UT WOS:000173916700004 ER PT S AU Andrews, RJ AF Andrews, RJ BE Slikker, W Trembly, B TI Monitoring for neuroprotection - New technologies for the new millennium SO NEUROPROTECTIVE AGENTS SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT 5th International Conference on Neuroprotective Agents CY SEP 17-21, 2000 CL LAKE TAHOE, NEVADA SP Natl Ctr Toxicol Res /FDA, Cent Arkansas Chapter Sigma Xi DE brain ischemia; cerebral oxygenation; neuromonitoring; neuroprotection; near infrared spectroscopy ID NEAR-INFRARED SPECTROSCOPY; SEVERE HEAD-INJURY; BRAIN-TISSUE OXYGEN; SUBSTRATE DELIVERY; INITIAL EXPERIENCE; PH; OXIMETRY; SURGERY; TENSION AB Monitoring for neuroprotection, like surgery, has placed an emphasis on minimal or non-invasiveness. Monitoring of parameters that truly reflect the degree of injury to the nervous system is another goal. Thus, two themes for the coming decade in neuromonitoring will be: (1) less-invasive monitoring; and (2) parameters that more closely reflect the etiological factors in ischemic or other neuroinjury. In this paper, we review neuromonitoring techniques and devices that can be used readily in the operating room or intensive care unit setting. Those that require transport of the patient to a special facility (e.g., for computed tomography or magnetic resonance imaging/spectroscopy) and those that have been in standard practice for neuromonitoring (e.g., electrophysiological monitoring-EEG, evoked potentials) are not considered. The two techniques considered in detail are (1) continuous multiparameter local brain tissue monitoring with microprobes, and (2) non-invasive continuous local brain tissue oxygenation monitoring by near infrared spectroscopy. Both techniques have been cleared by the Food and Drug Administration (FDA) for clinical use. The rationale for their use, the nature of the devices, and clinical results to date are reviewed. It is expected that both techniques will gain wide acceptance during the coming decade; further advances in neuromonitoring that can be expected further into the twenty-first century are also discussed. C1 Texas Tech Univ, Hlth Sci Ctr, Div Neurosurg, El Paso, TX 79905 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Stanford Univ, Med Ctr, Dept Neurosurg, Stanford, CA 94305 USA. RP Andrews, RJ (reprint author), Texas Tech Univ, Hlth Sci Ctr, Div Neurosurg, 4800 Alberta, El Paso, TX 79905 USA. NR 21 TC 7 Z9 8 U1 0 U2 2 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-352-1 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 2001 VL 939 BP 101 EP 113 PG 13 WC Multidisciplinary Sciences; Clinical Neurology SC Science & Technology - Other Topics; Neurosciences & Neurology GA BT12V UT WOS:000172028600013 PM 11462761 ER PT S AU Andrews, RJ AF Andrews, RJ BE Slikker, W Trembly, B TI Neuroprotection for the new millennium - Matchmaking pharmacology and technology SO NEUROPROTECTIVE AGENTS SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT 5th International Conference on Neuroprotective Agents CY SEP 17-21, 2000 CL LAKE TAHOE, NEVADA SP Natl Ctr Toxicol Res /FDA, Cent Arkansas Chapter Sigma Xi DE brain stimulation; excitotoxic injury; minimally invasive surgery; movement disorders; neuroprotection; Parkinson's disease; subthalamic nucleus ID MULTIPLE ORGAN FAILURE; PARKINSONS-DISEASE; ELECTRICAL-STIMULATION; SUBTHALAMIC NUCLEUS; MOVEMENT-DISORDERS; BRAIN-STIMULATION; 2 PARTS; SURGERY AB A major theme of the 1990s in the pathophysiology of nervous system injury has been the multifactorial etiology of irreversible injury. Multiple causes imply multiple opportunities for therapeutic intervention-hence the abandonment of the " magic bullet " single pharmacologic agent for neuroprotection in favor of pharmacologic " cocktails ". A second theme of the 1990s has been the progress in technology for neuroprotection, minimally- or non-invasive monitoring as well as treatment. Cardiac stenting has eliminated the need, in many cases, for open heart surgery; deep brain stimulation for Parkinson's disease has offered significant improvement in quality of life for many who had exhausted cocktail drug treatment for their disease. Deep brain stimulation of the subthalamic nucleus offers a novel treatment for Parkinson's disease where a technological advance may actually be an intervention with effects that are normally expected from pharmacologic agents. Rather than merely " jamming " the nervous system circuits involved in Parkinson's disease, deep brain stimulation of the subthalamic nucleus appears to improve the neurotransmitter imbalance that lies at the heart of Parkinson's disease. It may also slow the progression of the disease. Given the example of deep brain stimulation of the subthalamic nucleus for Parkinson's disease, in future one may expect other technological or " hardware " interventions to influence the programming or " software " of the nervous system's physiologic response in certain disease states. C1 Texas Tech Univ, Hlth Sci Ctr, Div Neurosurg, El Paso, TX 79905 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Stanford Univ, Med Ctr, Dept Neurosurg, Stanford, CA 94305 USA. RP Andrews, RJ (reprint author), Texas Tech Univ, Hlth Sci Ctr, Div Neurosurg, 4800 Alberta, El Paso, TX 79905 USA. NR 24 TC 6 Z9 6 U1 0 U2 2 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-352-1 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 2001 VL 939 BP 114 EP 125 PG 12 WC Multidisciplinary Sciences; Clinical Neurology SC Science & Technology - Other Topics; Neurosciences & Neurology GA BT12V UT WOS:000172028600014 PM 11462763 ER PT J AU Post, RB Caufield, KJ Welch, RB AF Post, RB Caufield, KJ Welch, RB TI Contributions of object- and space-based mechanisms to line bisection errors SO NEUROPSYCHOLOGIA LA English DT Article DE bisection; object-based; space-based; visual field ID LEFT-SIDE UNDERESTIMATION; VISUAL NEGLECT; INDIVIDUAL VARIATION; UNILATERAL NEGLECT; HAND; DISTORTION; ATTENTION AB in two experiments, normal adults divided a horizontal line segment and an equal spatial interval that did not contain a line into eight equal-appearing segments bq; means of successive bisections. In the first experiment, subjects' average initial bisections erred to the left of objective center for both stimuli. Their subsequent bisections produced similar errors for the line-present stimulus. as the bisection of each progressively smaller line segment was placed to the left of true center. However. this pattern did not occur when bisecting the empty interval. The finding that the presence of a line influences bisection errors implicates an 'object-based' mechanism in the genesis of line bisection errors and suggests that this mechanism varies in its operation with visual field location. In the second experiment. subjects successively bisected longer line and interval stimuli which were presented either centered on the subjects' midlines or displaced to the right or left. Bisections tended to be placed farther to the left for the left stimuli and farther to the right for the right stimuli. with little or no bias for the centrally located stimuli. Repeated measures with the centrally located stimulus demonstrated strong individual differences in bisection biases. Errors were also found to be correlated for the line-present and line-absent stimuli in both experiments. suggesting the additional contribution of a mechanism that is not object-based. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Davis, Dept Psychol, Davis, CA 95616 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Post, RB (reprint author), Univ Calif Davis, Dept Psychol, Davis, CA 95616 USA. NR 24 TC 22 Z9 22 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0028-3932 J9 NEUROPSYCHOLOGIA JI Neuropsychologia PY 2001 VL 39 IS 8 BP 856 EP 864 DI 10.1016/S0028-3932(01)00010-0 PG 9 WC Behavioral Sciences; Neurosciences; Psychology, Experimental SC Behavioral Sciences; Neurosciences & Neurology; Psychology GA 442WF UT WOS:000169307400009 PM 11369408 ER PT B AU Kazanas, D AF Kazanas, D BE Kouveliotou, C Ventura, J VandenHeuvel, E TI Modeling the time variability of black hole candidates SO NEUTRON STAR - BLACK HOLE CONNECTION SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT NATO Advanced Study Institute on the Neutron Star - Black Hole Connection CY JUN 07-18, 1999 CL ELOUNDA, GREECE SP NATO Sci Affairs Div ID ACCRETING COMPACT SOURCES; X-RAYS AB I present a model for the aperiodic variablity of accreting Black Hole Candidates (BHC) along with model light curves. According to the model this variability is the combined outcome of random (Poisson) injection of soft photons near the center of an extended inhomogeneous distribution of hot electrons (similar to those advocated by the ADAF or ADIOS flows) and the stochastic nature of Compton scattering which converts these soft photons into the observed high energy radiation. Thus, the timing properties (PSD, lags, coherence) of the BHC light curves reflect, to a large extent, the properties of the scattering medium (which in this approximation acts as a combination of a linear amplifier/filter) and they can be used to probe its structure, most notably the density profile of the scattering medium. The model accounts well for the observed PSDs and lags and also the reduction in the RMS variability and the increase in the characteristic PSD frequencies with increasing source luminosity. The electron density profiles obtained to date are consistent mainly with those of ADIOS but also with pure ADAF flows. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Kazanas, D (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 661, Greenbelt, MD 20771 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0204-1 J9 NATO SCI SER II MATH PY 2001 VL 567 BP 319 EP 324 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU29N UT WOS:000175586800022 ER PT B AU Fishman, GJ AF Fishman, GJ BE Kouveliotou, C Ventura, J VandenHeuvel, E TI Gamma-ray bursts: History and observations SO NEUTRON STAR - BLACK HOLE CONNECTION SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT NATO Advanced Study Institute on the Neutron Star - Black Hole Connection CY JUN 07-18, 1999 CL ELOUNDA, GREECE SP NATO Sci Affairs Div ID 28 FEBRUARY 1997; BATSE OBSERVATIONS; HIGH-ENERGY; SPECTRAL CHARACTERISTICS; BLACK-HOLES; TIME; EVOLUTION; AFTERGLOW; IDENTIFICATION; EMISSION AB Gamma-ray bursts (GRBs) are the most luminous objects known in the Universe. Their brief, random appearance in the gamma-ray region had made their study difficult since their discovery over thirty years ago. The discovery of counterparts to gamma-ray bursts and afterglow radiation in other wavelengths has provided the long-sought breakthrough in the direct determination of their distance and luminosity scales. The observed time profiles, spectral extent and durations of gamma-ray bursts are now well-sampled, with a catalog of over 2700 GRBs. There is a rich diversity in the duration and morphology of GRB time profiles. The spectra are characterized by a smooth continuum, usually peaking in the range from 0.1 MeV to 1 MeV. This applies to the integrated burst spectra as well as to spectra over limited temporal segments. Delayed gamma-ray burst photons extending to GeV energies have been detected. Since GRBs are produced at cosmological distances, they are expected to become unique tools for studying the conditions of the early Universe. C1 NASA, George C Marshall Space Flight Ctr, Dept Space Sci, Huntsville, AL 35812 USA. RP Fishman, GJ (reprint author), NASA, George C Marshall Space Flight Ctr, Dept Space Sci, Code SD 50, Huntsville, AL 35812 USA. NR 60 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0204-1 J9 NATO SCI SER II MATH PY 2001 VL 567 BP 417 EP 429 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU29N UT WOS:000175586800030 ER PT B AU Weisskopf, MC AF Weisskopf, MC BE Kouveliotou, C Ventura, J VandenHeuvel, E TI The Chandra X-ray Observatory (CXO) SO NEUTRON STAR - BLACK HOLE CONNECTION SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT NATO Advanced Study Institute on the Neutron Star - Black Hole Connection CY JUN 07-18, 1999 CL ELOUNDA, GREECE SP NATO Sci Affairs Div ID CALIBRATION; AXAF C1 NASA, MSFC, Marshall Space Flight Ctr, AL 35801 USA. RP Weisskopf, MC (reprint author), NASA, MSFC, SD-50, Marshall Space Flight Ctr, AL 35801 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-0204-1 J9 NATO SCI SER II MATH PY 2001 VL 567 BP 477 EP 491 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU29N UT WOS:000175586800034 ER PT B AU Mushotzky, R Angelini, L Loewenstein, M AF Mushotzky, R Angelini, L Loewenstein, M BE Inoue, H Kunieda, H TI Chandra observations of X-ray binaries in elliptical galaxies and upper limits on emission from central massive objects SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Mushotzky, R (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 64 EP 67 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500012 ER PT B AU Kubota, A Makishima, K Ebisawa, K AF Kubota, A Makishima, K Ebisawa, K BE Inoue, H Kunieda, H TI X-ray study of optically thick accretion disks around stellar black holes - the standard accretion disk and beyond SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN ID GRO J1655-40; MASS AB Analysis was made of the multiple RXTEIPCA data on the black hole candidate with superluminal jet, GRO J1655 - 40, acquired during its 1996-1997 outburst. The source spectra can be adequately described by the sum of a multi-color disk spectrum (MCD) and a power-law. When the power-law luminosity is high, the inner disk radius and the maximum color temperature derived from the MCD model vary significantly with time. In this strong power-law state, the MCD luminosity decreases with temperature, in contradiction to the prediction of the standard Shakura-Sunyaev model. In the same state, the intensity of the power-law component correlates negatively with that of the MCD component, and positively with the power-law photon index, suggesting that the strong power-law is simply the missing MCD emission. One possible explanation for this behavior is inverse-Compton scattering in the disk. By re-fitting the same data incorporating a disk Comptonization, the inner radius and temperature of the underlying disk are found to become more constant. C1 Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Kubota, A (reprint author), Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan. NR 10 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 80 EP 83 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500015 ER PT B AU Mukai, K Kallman, T Schlegel, E Bruch, A Handler, G Kemp, J AF Mukai, K Kallman, T Schlegel, E Bruch, A Handler, G Kemp, J BE Inoue, H Kunieda, H TI Chandra HETG observation of the magnetic cataclysmic variable V1223 Sagittarii SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN ID IRON AB V1223 Sgr is among the brightest magnetic cataclysmic variables in the 1-10 keV band, with a 3.36 hr orbital period and a 745.6 s spin period. Here we report selected results from our Chandra HETG observation, performed on 2000 April 30/May 1. We have detected Kalpha lines of many atomic species in the phase-averaged HETG spectrum. We find that the Fe L lines are substantially weaker than would be expected in a collisionally excited plasma. The ratios of helium-like triplets indicate a high density. We also find evidence of an ionized absorber. We suggest the accretion flow just before it reaches the shock is the likely location for both the absorber and the low energy line emitter. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lab Nacl Astrofis, BR-37500000 Itajuba, MG, Brazil. S African Astron Observ, ZA-7935 Cape Town, South Africa. Joint Astron Ctr, Hilo, HI 96720 USA. RP Mukai, K (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. NR 4 TC 8 Z9 8 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 90 EP 93 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500017 ER PT B AU Swank, J Markwardt, C AF Swank, J Markwardt, C BE Inoue, H Kunieda, H TI Populatious of transient galactic bulge X-ray sources SO NEW CENTURY OF X-RAY ASTRONOMY SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN AB Starting in 1999, the Rossi X-ray Timing Explorer (RXTE) has monitored the central bulge region of the Galaxy with the Proportional Counter Array (PCA), resolving about 50 binary X-ray sources, including 18 sources discovered by RXTE and BeppoSAX. The accretion rates that RXTE observed from these sources ranged from highs approaching Eddington limits to lows that may correspond to mass exchange for a binary period near the minimum of 80 minutes. Several neutron star binaries with low peak luminosity have outburst or cycle time-scales which are shorter than those of brighter and better known counterparts. We compare the characteristics of the binaries with low rates of mass exchange to predictions of their evolution. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM swank@lheamail.gsfc.nasa.gov NR 13 TC 37 Z9 37 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 94 EP 97 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500018 ER PT B AU Weisskopf, MC Tennant, AF Becker, W Juda, M Elsner, RF Kolodziejczak, JJ Murray, SS Paerels, F Swartz, DA Shibazaki, N O'Dell, SL AF Weisskopf, MC Tennant, AF Becker, W Juda, M Elsner, RF Kolodziejczak, JJ Murray, SS Paerels, F Swartz, DA Shibazaki, N O'Dell, SL BE Inoue, H Kunieda, H TI Chandra observations of the crab pulsar as a function of pulse phase SO NEW CENTURY OF X-RAY ASTRONOMY SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN ID NEUTRON-STAR; EMISSION; CASSIOPEIA; RADIATION; NEBULA AB The Chandra X-ray Observatory was used to observe the Crab Nebula and its pulsar using the LETGS, i.e. the Low-Energy Transmission Grating (LETG) with the High Resolution Camera Spectroscopy detector (HRC-S). Data from the zeroth-order image was utilized to isolate the pulsar from the surrounding nebula and to measure the pulsar emission as a function of pulse phase. HRC timing problems were overcome by developing special techniques to process the data. For the first time, pulsed X-ray emission has been detected at all pulse phases, allowing us to set a new upper limit to the thermal emission from the surface of the neutral star. C1 NASA, George C Marshall Space Flight Ctr, Dept Space Sci, MSFC, Huntsville, AL 35812 USA. RP Weisskopf, MC (reprint author), NASA, George C Marshall Space Flight Ctr, Dept Space Sci, MSFC, SD50, Huntsville, AL 35812 USA. EM martin@smoker.msfc.nasa.gov; shibazak@rikkyo.ac.jp NR 13 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 98 EP 101 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500019 ER PT B AU Porter, FS Behar, E Beiersdorfer, P Boyce, KR Brown, GV Chen, H Gendreau, KC Gygax, J Kahn, SM Kelley, RL Stahle, K Szymkowiak, AE AF Porter, FS Behar, E Beiersdorfer, P Boyce, KR Brown, GV Chen, H Gendreau, KC Gygax, J Kahn, SM Kelley, RL Stahle, K Szymkowiak, AE BE Inoue, H Kunieda, H TI Laboratory astrophysics using an XRS engineering model microcalorimeter SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN AB Laboratory astrophysics measurements and their impact on guiding and verifying atomic codes are becoming increasingly important in the era of Chandra and XMM. We have recently added an XRS engineering model micro calorimeter array to the spectrometers used at the EBIT II facility at LLNL to observe collisionally excited plasmas of astrophysically interesting elements. Specifically we have observed Fe L and K shell emission for a wide range of electron temperatures, monoenergetic energies, and ionization conditions. Here we briefly discuss the XRS spectrometer as it is configured for the EBIT II facility and some of the first results. As an example we detail the measurement of absolute Fe L emission cross sections for Fe XXIV. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Porter, FS (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; NR 3 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 184 EP 187 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500037 ER PT B AU Stahle, CK Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Gygax, JD Kelley, RL Li, MJ Lindeman, MA Stahle, CA Tralshawala, N AF Stahle, CK Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Gygax, JD Kelley, RL Li, MJ Lindeman, MA Stahle, CA Tralshawala, N BE Inoue, H Kunieda, H TI Progress in developing close-packed X-ray microcalorimeter arrays of Mo/Au transition-edge sensors SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN AB X-ray microcalorimeters using transition-edge sensors (TES) show great promise for use in astronomical x-ray spectroscopy. We have obtained very high energy resolution (2.4 eV at 1.5 keV and 3.7 eV at 3.3 keV) in large, isolated TES pixels using Mo/Au proximity-effect bilayers on silicon nitride membranes. In order to be truly suitable for use behind an X-ray telescope, however, such devices need to be arrayed with a pixel size and focal-plane coverage matched to the telescope focal length and spatial resolution. This requires fitting the TES and its thermal link, a critical component of each calorimeter pixel, into a far more compact geometry than has previously been investigated. We are addressing the tradeoffs that must be made to accommodate a smaller sensor area and are exploring the range in thermal conductance that can be obtained by perforating the nitride membrane in a narrow perimeter around the sensor. We have already demonstrated that such compact pixel geometries can yield suitable thermal conductance values. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Stahle, CK (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Kelley, Richard/K-4474-2012 NR 5 TC 0 Z9 0 U1 0 U2 2 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 188 EP 191 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500038 ER PT B AU White, NE Tananbaum, H AF White, NE Tananbaum, H BE Inoue, H Kunieda, H TI The constellation x-ray mission SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN ID TRANSITION-EDGE-MICROCALORIMETER; EV ENERGY RESOLUTION AB The Constellation-X mission is a large collecting area X-ray observatory emphasizing high spectral resolution (R = E/DeltaE from 300 to 3000) and a broad energy band (0.25 to 60 keV). By increasing the telescope aperture and utilizing efficient spectrometers the mission will achieve a factor of 20 to 100 increased sensitivity over current high resolution X-ray spectroscopy missions. The use of focusing optics across the 10 to 60 keV band will provide a similar factor of 100 increased sensitivity in this band. The Constellation-X design divides the collecting area across four separate spacecraft, launched two at a time. Constellation-X will address many topics including observing the formation and evolution of clusters of galaxies, constraining the Baryon content of the Universe, observing the effects of strong gravity close to the event horizon of super-massive black holes and the evolution of AGN with redshift. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP White, NE (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. RI White, Nicholas/B-6428-2012 OI White, Nicholas/0000-0003-3853-3462 NR 7 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 224 EP 229 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500046 ER PT B AU Harrus, IM Holt, S Hwang, U Petre, R Stahle, CK Szymkowiak, A AF Harrus, IM Holt, S Hwang, U Petre, R Stahle, CK Szymkowiak, A BE Inoue, H Kunieda, H TI Chandra results from Kepler's supernova remnant SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN ID X-RAY-EMISSION; EXPANSION AB Kepler's supernova remnant (SN 1604) appears as an almost perfectly circular shell whose western edge is brighter in X-rays. The SNR cannot be fit by a single model (equilibrium or non-equilibrium ionization models). In this poster, we have concentrated on the front shock and study the different regions of X-ray emission. C1 NASA, Goddard Space Flight Ctr, USRA, Greenbelt, MD 20771 USA. RP Harrus, IM (reprint author), NASA, Goddard Space Flight Ctr, USRA, Code 661, Greenbelt, MD 20771 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 242 EP 243 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500050 ER PT B AU Iping, RC AF Iping, RC BE Inoue, H Kunieda, H TI A model for eta Carinae as implied by RXTE, CHANDRA and FUSE observations SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN AB A model in which eta Carinae is a colliding wind massive binary system is presented. The Far Ultraviolet Spectroscopic Explorer satellite (FUSE) observed eta Carinae in February and March 2000. In addition to many strong interstellar atomic species, the spectrum contains several prominent P-Cygni features, including C III 1175, S IV 1063-73, Si III 1113, and N I 1134. The wind absorption extends to similar to 1000 km s(-1). The observed terminal velocity of 1000 km/s by the FUSE satellite together with the observed 500 km/s by STIS establishes the binary nature of eta Carinae, in which the terminal velocities mentioned are those of the companion and of eta Carinae respectively. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Iping, RC (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 248 EP 249 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500053 ER PT B AU Stahle, CK Petre, R Hwang, U Harrus, IM Holt, SS AF Stahle, CK Petre, R Hwang, U Harrus, IM Holt, SS BE Inoue, H Kunieda, H TI ACIS imaging and spectroscopy of the SNR W49B SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN ID SUPERNOVA REMNANT W49B; EMISSION AB We present preliminary results of a Chandra ACIS observation of the ejecta-dominated Galactic SNR W49B. This remnant is known from previous observations (e.g., Fujimoto et al. 1995) to have strong emission lines from Si and S, and Fe. Narrow band ASCA images had suggested that the Fe is more centrally concentrated than the Si and S. We have used narrow band ACIS images to test this hypothesis. We have also used spectra from selected regions to investigate abundance and ionization variations across the remnant. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Stahle, CK (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 278 EP 279 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500068 ER PT B AU Ebisawa, K Maeda, Y Kaneda, H Yamauchi, S AF Ebisawa, K Maeda, Y Kaneda, H Yamauchi, S BE Inoue, H Kunieda, H TI Chandra observation of a blank Galactic plane region SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN ID RAY AB We have carried out a Chandra ACIS-I observation on a typical Galactic plane where no previous X-ray sources have been known. We have discovered more than 50 unidentified sources in the 3-8 keV band above the flux level similar to 3 x 10(-15) ergs/s/cm(2) at the 3 sigma confidence level. The total point source flux accounts for only 10 % of the total X-ray flux in the field of view. The observed source number density shows little excess over the extragalactic log N - log S curve determined from high Galactic latitude regions. The present result indicates that significant parts of the detected sources have extragalactic origin. The Galactic Ridge hard X-ray Emission has truly diffuse origin, and there are few Galactic X-ray sources as dim as similar to 3 x 10(-15) ergs/s/cm(2) (2 - 10 keV). C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ebisawa, K (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 298 EP 299 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500077 ER PT B AU Boyce, KR Irwin, KA Figueroa-Feliciano, E Finkbeiner, FM Gendreau, KC Kelley, RL Lindeman, MA Porter, FS Stahle, CK Szymkowiak, AE AF Boyce, KR Irwin, KA Figueroa-Feliciano, E Finkbeiner, FM Gendreau, KC Kelley, RL Lindeman, MA Porter, FS Stahle, CK Szymkowiak, AE BE Inoue, H Kunieda, H TI Data handling considerations for large microcalorimeter arrays SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN AB Future missions such as Constellation-X (White 2001) plan to use arrays of 1000 or more micro calorimeters with peak count rates of 1000 per second on a single pixel and 10,000 per second across the array. These requirements put severe constraints on the readout and data processing system. We discuss sampling rate requirements, noise considerations, and possible readout schemes. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Boyce, KR (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; NR 1 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 522 EP 523 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500186 ER PT B AU Brown, GV Behar, E Beiersdorfer, P Boyce, KR Chen, H Gendreau, KC Gygax, J Kahn, SM Kelley, RL Porter, FS Stahle, CK Szymkowiak, AE AF Brown, GV Behar, E Beiersdorfer, P Boyce, KR Chen, H Gendreau, KC Gygax, J Kahn, SM Kelley, RL Porter, FS Stahle, CK Szymkowiak, AE BE Inoue, H Kunieda, H TI Recent results from EBIT-II using a spare Astro-E microcalorimeter SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN AB A spare NASA/GSFC Astro-E microcalorimeter has been installed, tested, and run successfully on EBIT-II at the Lawrence Liver-more National Laboratory. A brief overview of results including measurements by the micro calorimeter of absolute excitation cross sections, time dependent spectra, and spectra as a function of Maxwellian temperature are discussed. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Brown, GV (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; NR 4 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 524 EP 525 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500187 ER PT B AU Figueroa-Feliciano, E Stahle, CK Finkbeiner, FM Li, M Lindeman, MA Tralshawala, N Stahle, CM AF Figueroa-Feliciano, E Stahle, CK Finkbeiner, FM Li, M Lindeman, MA Tralshawala, N Stahle, CM BE Inoue, H Kunieda, H TI First light of position-sensing transition-edge sensors SO NEW CENTURY OF X-RAY ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on New Century of X-Ray Astronomy CY MAR 06-08, 2001 CL YOKOHAMA, JAPAN AB We report the first light of a absorber-multiplexing imaging calorimeter called a Position-Sensing Transition-Edge Sensor (PoST). We have obtained 30 eV FWHM at 1.5 keV with this device. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Figueroa-Feliciano, E (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-091-9 J9 ASTR SOC P PY 2001 VL 251 BP 532 EP 533 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU69N UT WOS:000176731500191 ER PT S AU Erzberger, H McNally, D Foster, M Chiu, D Stassart, P AF Erzberger, H McNally, D Foster, M Chiu, D Stassart, P BE Bianco, L DellOlmo, P Odoni, AR TI Direct-to tool for en route controllers SO NEW CONCEPTS AND METHODS IN AIR TRAFFIC MANAGEMENT SE TRANSPORTATION ANALYSIS LA English DT Proceedings Paper CT International Workshop on Air Traffic Management CY SEP 26-30, 1999 CL CAPRI, ITALY SP Italian Natl Res Council, Univ Rome Tor Vergata, MIT DE air traffic management; air traffic control; aircraft trajectory optimization AB The Direct-To Tool helps controllers identify all aircraft in their airspace that can reduce the time of flight en route by flying "direct-to" a waypoint on their flight plan located closer to the destination airport. The Tool provides controllers with a list of all aircraft eligible for a direct -to clearance, ordered by minutes saved In addition to the call sign (ACID) of the eligible aircraft and the potential time saving, the list also includes the name of the waypoint for the direct -to clearance to be issued as to well as the conflict status of the direct- to trajectory. The trajectory analysis and conflict detection algorithm that generates the list of eligible direct-to aircraft uses the trajectory synthesis engine built into the CTAS software. The Direct-To trajectory is sent to the Center's host computer via the CTAS-to-host data link, where it is registered as a flight plan amendment. After completing the amendment transaction, the controller would issue the Direct-To clearance to the pilot of the aircraft. Operation of the Tool in the Fort Worth Center is estimated to save more than 1000 minutes of flight time per day. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 1431-9373 BN 3-540-41637-4 J9 TRANSPORTATION ANALY PY 2001 BP 179 EP 198 PG 20 WC Transportation; Transportation Science & Technology SC Transportation GA BU05T UT WOS:000174876400011 ER PT B AU Williger, GM Campusano, LE Clowes, RG AF Williger, GM Campusano, LE Clowes, RG BE Clowes, R Adamson, A Bromage, G TI Mg (II) absorbers toward a large quasar group at 1.20 z 1.38 SO NEW ERA OF WIDE FIELD ASTRONOMY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT International Conference on the New Era of Wide Field Astronomy CY AUG 21-24, 2000 CL UNIV CENT LANCASHIRE, PRESTON, ENGLAND HO UNIV CENT LANCASHIRE ID EVOLUTION AB We have conducted a survey for Mg-II absorber systems toward the largest structure in the sky at z > 0.2, a large quasar group (LQG) consisting of at least 15 quasars at 1.20 < z < 1.38 toward ESO/SERC field 927 (Clowes & Campusano 1991). It spans at least similar to 5degrees x 2.5degrees on the sky (similar to 200 x 100h(-2) Mpc(2)) and depth 156 (210) h(-1) comoving Mpc for Omega(0) = 1 (Omega(0) = 0.2), H-0 equivalent to 100h km s(-1) Mpc(-1), Lambda = 0. It is one of a handful of large quasar groups (Graham, Clowes, & Campusano 1995), which are believed to indicate a physical enhancement in the underlying density of the universe when the universe was about 1/3 of its present age. We can test for this mass excess by searching for spatially correlated metal absorption line systems, seen in the spectra of quasars situated in the background of the group. We have obtained spectra of 23 quasars, with z > 1.2 distributed over a similar to 2 x 2degrees area embedded in the quasar group, to survey for Mg-II at 0.70 < z < 2.07. The redshift distribution of our Mg-II sample is consistent with a random distribution only with probability P = 0.005, which is caused by a 4.7sigma excess of Mg-II absorbers coincident with the main body of the LQG at 1.20 < z < 1.30. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Williger, GM (reprint author), NASA, Goddard Space Flight Ctr, Code 681, Greenbelt, MD 20771 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-065-X J9 ASTR SOC P PY 2001 VL 232 BP 114 EP 116 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU31N UT WOS:000175668200022 ER PT B AU Kao, D Pang, A AF Kao, D Pang, A GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Advecting procedural textures for 2D flow animation SO NINTH PACIFIC CONFERENCE ON COMPUTER GRAPHICS AND APPLICATIONS, PROCEEDINGS LA English DT Proceedings Paper CT 9th Pacific Conference on Computer Graphics and Applications (Pacific Graphics 01) CY OCT 16-18, 2001 CL TOKYO, JAPAN SP Informat Proc Soc Japan DE procedural textures; critical points; texture advection; animation; vector field AB This paper proposes the use of specially generated 3D procedural textures for visualizing steady state 2D flow fields. We use the flow field to advect and animate the texture over time. However using standard texture advection techniques and arbitrary textures will introduce some undesirable effects such as: (a) expanding texture from a critical source point, (b) streaking pattern from the boundary of the flowfield, (c) crowding of advected textures near an attracting spiral or sink, and (d) absent or lack of textures in some regions of the flow. This paper proposes a number of strategies to solve these problems, We demonstrate how the technique works using both synthetic data and computational fluid dynamics data. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Kao, D (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1227-5 PY 2001 BP 355 EP 362 DI 10.1109/PCCGA.2001.962892 PG 8 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BT12Y UT WOS:000172028900040 ER PT S AU Abdul-Aziz, A Baaklini, GY Trudell, JJ AF Abdul-Aziz, A Baaklini, GY Trudell, JJ BE Baaklini, GY Boltz, ES Shepard, SM Shull, PJ TI An integrated NDE and FEM characterization of composite rotors SO NONDESTRUCTIVE EVALUATION OF MATERIALS AND COMPOSITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Nondestructive Evaluation of Materials and Composites V Conference CY MAR 07-08, 2001 CL NEWPORT BEACH, CA SP SPIE DE finite element analysis; computed topography; stress analysis; flywheels; fracture mechanics; nondestructive evaluation; FEM; NDE; composites AB A structural assessment by integrating finite-element methods (FEM) and a nondestructive evaluation (NDE) of two flywheel rotor assemblies is presented. Composite rotor A is pancake like with a solid hub design, and composite rotor B is cylindrical with a hollow hub design. Detailed analyses under combined centrifugal and interference-fit loading are performed. Two- and three-dimensional stress analyses and two-dimensional fracture mechanics analyses are conducted. A comparison of the structural analysis results obtained with those extracted via NDE findings is reported. Contact effects due to press-fit conditions are evaluated. Stress results generated from the finite-element analyses were corroborated with the analytical solution. Cracks due to rotational loading up to 48 000 rpm for rotor A and 34 000 rpm for rotor B were successfully imaged with NDE and predicted with FEM and fracture mechanics analyses. A procedure that extends current structural analysis to a life prediction tool is also defined. C1 Cleveland State Univ, Dept Civil & Environm Engn, NASA Glenn Res Ctr, Cleveland, OH 44135 USA. RP Abdul-Aziz, A (reprint author), Cleveland State Univ, Dept Civil & Environm Engn, NASA Glenn Res Ctr, 1000 Brookpark Rd,MS 6-1, Cleveland, OH 44135 USA. NR 17 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4022-1 J9 P SOC PHOTO-OPT INS PY 2001 VL 4336 BP 43 EP 54 DI 10.1117/12.435574 PG 12 WC Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Materials Science, Composites SC Materials Science GA BT33X UT WOS:000172675000006 ER PT S AU Gyekenyesi, AL Baaklini, GY AF Gyekenyesi, AL Baaklini, GY BE Baaklini, GY Boltz, ES Shepard, SM Shull, PJ TI Rotor health monitoring and damage detection utilizing a disk spin simulation system SO NONDESTRUCTIVE EVALUATION OF MATERIALS AND COMPOSITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Nondestructive Evaluation of Materials and Composites V Conference CY MAR 07-08, 2001 CL NEWPORT BEACH, CA SP SPIE AB This paper describes a unique, disk spin simulation system currently being utilized at NASA Glenn Research Center. The system allows for precision controlled spin tests that can facilitate the application of various sensing technologies for in-situ detection of rotor damage. In addition, the disk spin simulation system has the capability for elevated temperatures up to 540 degreesC (1000 degreesF). The current rotor used to simulate a bladed disk consists of a 46 cm (18 in.) diameter, titanium disk with 30 machined gear teeth. The gear design imitates the blades of a compressor or turbine disk. Operating speeds for the system can reach 10000 revolutions per minute. This allows the system to achieve circumferential velocities paralleling those seen in actual aircraft engines. For this study, a new, innovative capacitive sensing system was used to monitor blade tip clearance (i.e., gear tooth clearance). In turn, the sensor information was employed to calculate the change in the center of mass of the rotor system. The capacitive sensor and corresponding software were analyzed by attaching a localized weight at numerous positions on the disk. Upon calculating the change in the center of mass, the sensitivities of the sensor and software were established. In the end, it is hoped that by studying the motion and position of blades as well as the change in the center of mass of a rotor system, it may be feasible to identify alterations due to damage (e.g., cracks) either in the blades or the disk itself. C1 NASA, Glenn Res Ctr, Cleveland, OH 44115 USA. RP Gyekenyesi, AL (reprint author), NASA, Glenn Res Ctr, 21000 Brookpk Rd,MS 6-1, Cleveland, OH 44115 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4022-1 J9 P SOC PHOTO-OPT INS PY 2001 VL 4336 BP 160 EP 166 DI 10.1117/12.435562 PG 7 WC Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Materials Science, Composites SC Materials Science GA BT33X UT WOS:000172675000019 ER PT S AU Bonometti, JA Buchele, D Castle, C Gregory, D AF Bonometti, JA Buchele, D Castle, C Gregory, D BE Winston, R TI Solar thermal plasma chamber SO NONIMAGING OPTICS: MAXIMUM EFFICIENCY LIGHT TRANSFER VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 6th Biannual Conference on Nonimaging Optics: Maximum Efficiency Light Transfer CY AUG 02-03, 2001 CL SAN DIEGO, CA SP SPIE DE solar; thermal; optics; image-forming; plasma; rocket; high-temperature; reflection; absorption; experiment AB A unique solar thermal chamber has been designed and fabricated to produce the maximum concentration of solar energy and highest temperature possible. Its primary purpose was for solar plasma propulsion experiments and related material specimen testing above 3000 Kelvin. The design not only maximized solar concentration, but also, minimized infrared heat loss. This paper provides the underlining theory and operation of the chamber and initial optical correlation to the actual fabricated hardware. The chamber is placed at the focal point of an existing primary concentrator with a 2.74-meter (9 foot) focal length. A quartz lens focuses a smaller sun image at the inlet hole of the mirrored cavity. The lens focuses two image planes at prescribed positions; the sun at the cavity's entrance hole, and the primary concentrator at the junction plane of two surfaces that form the cavity chamber. The back half is an ellipsoid reflector that produces a 1.27 cm diameter final sun image. The image is "suspended in space", 7.1cm away from the nearest cavity surface, to minimize thermal and contaminate damage to the mirror surfaces. A hemisphere mirror makes up the front chamber and has its center of curvature at the target image, where rays leaving the target are reflected back upon themselves, minimizing radiation losses. C1 NASA, George C Marshall Space Flight Ctr, Adv Concepts Dept, Huntsville, AL 35812 USA. RP Bonometti, JA (reprint author), NASA, George C Marshall Space Flight Ctr, Adv Concepts Dept, TD-30, Huntsville, AL 35812 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4160-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4446 BP 129 EP 140 DI 10.1117/12.448813 PG 12 WC Optics SC Optics GA BT74Q UT WOS:000173938900014 ER PT S AU Fixsen, DJ AF Fixsen, DJ BE Winston, R TI Multimode antenna optimization SO NONIMAGING OPTICS: MAXIMUM EFFICIENCY LIGHT TRANSFER VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 6th Biannual Conference on Nonimaging Optics: Maximum Efficiency Light Transfer CY AUG 02-03, 2001 CL SAN DIEGO, CA SP SPIE ID MILLIMETER AB The design and optimization of the TOPHAT feed horn is presented. This horn is a nonimaging antenna with a few modes. Diffraction effects are approximated using ray-trace techniques with the addition of phase information. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fixsen, DJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 12 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4160-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4446 BP 161 EP 170 DI 10.1117/12.448815 PG 10 WC Optics SC Optics GA BT74Q UT WOS:000173938900018 ER PT S AU Howard, JM Stone, BD AF Howard, JM Stone, BD BE Sasian, JM Manhart, PK TI Imaging with multi-reflection systems of two spherical mirrors SO NOVEL OPTICAL SYSTEMS DESIGN AND OPTIMIZATION IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Conference on Novel Optical Systems Design and Optimization CY AUG 01-02, 2001 CL SAN DIEGO, CA SP SPIE DE geometrical optics; optical design; lens design; mirrors; reflective optics; spherical mirrors; global optimization AB We investigate unobstructed plane-symmetric imaging systems of two spherical mirrors having three- or four-reflections. Geometry constraints are used to ensure that the odd numbered reflections occur on one spherical mirror, and that even numbered reflections occur on a separate spherical mirror. Imaging constraints are used to ensure appropriate first-order behavior. These geometry and imaging constraints eliminate degrees of freedom from the configuration space, thereby simplifying the design process. For the three-reflection systems, the available degrees of freedom are reduced to four, and for four-reflection systems, they are reduced to five. An alternate method using pickup constraints is discussed. Global optimization using simulated annealing is performed, and example systems are presented. C1 NASA, Goddard Space Flight Ctr, Opt Branch, Greenbelt, MD 20771 USA. RP Howard, JM (reprint author), NASA, Goddard Space Flight Ctr, Opt Branch, Code 551, Greenbelt, MD 20771 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4156-2 J9 P SOC PHOTO-OPT INS PY 2001 VL 4442 BP 51 EP 59 DI 10.1117/12.449958 PG 9 WC Optics SC Optics GA BT90M UT WOS:000174395600007 ER PT J AU Turner, MS AF Turner, MS TI Dark energy SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XIXTH International Conference on neutrino Physics and Astrophysics CY JUN 16-21, 2000 CL LAURENTIAN UNIV, SUDBURY, CANADA HO LAURENTIAN UNIV ID STRING-DOMINATED UNIVERSE; COSMOLOGICAL CONSTANT; QUINTESSENCE; SUPERNOVAE; COMPONENT; FIELD AB The discovery that the Universe is speeding up and not slowing down was greeted with open arms by theorists. First, because the dark energy powering the acceleration provided the energy needed to make the Universe flat, in accord with a key prediction of inflation. Second, because theorists now have a new puzzle to solve, the nature of the mysterious dark energy. I have no doubt that the dark energy problem will be just as fundamental and just as interesting as the dark matter problem. Determining its nature will require the work of both astronomers and particle physics and will shed light on both fundamental physics and the fate of the Universe. C1 Univ Chicago, Enrico Fermi Inst, Dept Astron & Astrophys Phys, Chicago, IL 60637 USA. NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Turner, MS (reprint author), Univ Chicago, Enrico Fermi Inst, Dept Astron & Astrophys Phys, Chicago, IL 60637 USA. NR 28 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 2001 VL 91 BP 405 EP 409 DI 10.1016/S0920-5632(00)00969-5 PG 5 WC Physics, Particles & Fields SC Physics GA 396KZ UT WOS:000166636700055 ER PT J AU Kouatchou, J AF Kouatchou, J TI Finite differences and collocation methods for the solution of the two-dimensional heat equation SO NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS LA English DT Article DE heat equation; collocation methods; finite difference; fourth-order scheme ID 4TH-ORDER AB In this article, we combine finite difference approximations (for spatial derivatives) and collocation techniques (for the time component) to numerically solve the two-dimensional heat equation. We employ, respectively, second-order and fourth-order schemes for the spatial derivatives, and the discretization method gives rise to a linear system of equations. We show that the matrix of the system is nonsingular Numerical experiments carried out on serial computers show the unconditional stability of the proposed method and the high accuracy achieved by the fourth-order scheme. (C) 2001 John Wiley & Sons, Inc. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Morgan State Univ, Baltimore, MD 21239 USA. RP Kouatchou, J (reprint author), NASA, Goddard Space Flight Ctr, Code 931, Greenbelt, MD 20771 USA. RI Koutachou, Jules/D-4773-2016 OI Koutachou, Jules/0000-0002-5525-9875 NR 10 TC 6 Z9 6 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0749-159X J9 NUMER METH PART D E JI Numer. Meth. Part Differ. Equ. PD JAN PY 2001 VL 17 IS 1 BP 54 EP 63 DI 10.1002/1098-2426(200101)17:1<54::AID-NUM4>3.0.CO;2-A PG 10 WC Mathematics, Applied SC Mathematics GA 389CT UT WOS:000166221600004 ER PT S AU Blasi, P AF Blasi, P BE Salazar, H Villasenor, L Zepeda, A TI Dark matter distribution in the universe and ultra-high energy cosmic rays SO OBSERVING ULTRAHIGH ENERGY COSMIC RAYS FROM SPACE AND EARTH SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT International Workshop on Observing Ultra High Energy Cosmic Rays from Space and Earth CY AUG 09-12, 2000 CL METEPEC, MEXICO ID ZATSEPIN-KUZMIN CUTOFF; NEARBY GALAXIES; SPECTRUM; ANISOTROPY; FIELD; HALO; PARTICLES; REDSHIFT; DENSITY; DECAYS AB Two of the greatest mysteries of modern physics are the origin of the dark matter in the universe and the nature of the highest energy particles in the cosmic ray spectrum. We discuss here possible direct and indirect connections between these two problems, with particular attention to two cases: in the first we study the local clustering of possible sources of ultra-high energy cosmic rays (UHECRs) driven by the local dark matter overdensity. In the second case we study the possibility that UHECRs are directly generated by the decay of weakly unstable super heavy dark matter. C1 NASA, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. RP Blasi, P (reprint author), NASA, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. RI Blasi, Pasquale/O-9345-2015 OI Blasi, Pasquale/0000-0003-2480-599X NR 39 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0002-4 J9 AIP CONF PROC PY 2001 VL 566 BP 195 EP 210 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BS29C UT WOS:000169368100015 ER PT B AU Naughton, J Jokiel, PL AF Naughton, J Jokiel, PL GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Coral reef mitigation and restoration techniques employed in the Pacific Islands: I. Overview SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc ID KANEOHE BAY; HAWAII AB In the past two decades numerous reef mitigation and restoration projects have been undertaken throughout the world. This article summarizes our experience with a wide range of projects in Hawaii and the U. S. - affiliated Pacific Islands. The terms "mitigation" and "restoration" are often taken to mean reef repair, coral transplantation or construction of additional habitat (e.g. artificial reefs). However, other options are available and should be considered. In some situations removal of the anthropogenic factor causing the damage while allowing natural processes of recovery to occur is the best approach. Natural rates of reef recovery can be very rapid In such situations and direct human intervention on the reefs is unnecessary. In some instances a negotiated environmental settlement or financial penalties can be used to establish trust funds to offset environmental losses. Review of past attempts to mitigate reef damage and restore reefs suggests that managers must have a broad strategic plan and incorporate a wide range of approaches designed to fit each situation on a case by case basis. Although protection of the reefs must always be the top priority, there will inevitably be situations where damage will occur. In these situations restoration and mitigation measures will have to be considered. C1 Natl Marine Fisheries Serv, Pacific Isl Area Off, Honolulu, HI 96814 USA. RP Naughton, J (reprint author), Natl Marine Fisheries Serv, Pacific Isl Area Off, 1601 Kapiolani Blvd,Suite 1110, Honolulu, HI 96814 USA. NR 47 TC 1 Z9 1 U1 1 U2 9 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 306 EP 312 PG 7 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800047 ER PT B AU Liu, WT Xie, XS AF Liu, WT Xie, XS GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Improvement in spacebased scatterometers and increased scientific impact in the past decade SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc ID TROPICAL INSTABILITY WAVES AB The past decade has seen continuous improvement to the coverage and resolution of ocean surface winds by spacebased microwave scatterometers. The principles of scatterometry and the characteristics of these sensors are summarized. Examples of scientific applications with these improvements are given. The high quality and resolution of scatterometer winds allow improved study of tropical atmospheric convergence zones, particularly a southern intertropical convergence zone in the Atlantic. Recent scatterometer data describe the wind jets out of Central America with sufficient details to provide the forcing to simulate realistic coastal upwelling in ocean general circulation model. QuikSCAT reveals for the first time an ultra long wake composed of alternate high and low winds streaks and lines of positive and negative curl of wind stress; they stretch a few thousand kilometers from the west side of the Hawaii Islands to beyond Wake Islands in the western Pacific. QuikSCAT also reveal the atmospheric manifestation of the westward-propagating tropical instability waves in the equatorial Pacific. Scatterometers are capable of monitoring not only the ocean winds, which feed moisture towards land, but the consequent flooding of the land. Flooding in Asia, resulting from monsoon and typhoons are described. The plan for future missions and proposed new technology will be presented. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Liu, WT (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 626 EP 630 PG 5 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800099 ER PT B AU Rodgers, DH Beauchamp, PM Chave, AD Gaudet, S Kirkham, H Maffei, A Massion, G McGinnis, TM Wilcock, WSD AF Rodgers, DH Beauchamp, PM Chave, AD Gaudet, S Kirkham, H Maffei, A Massion, G McGinnis, TM Wilcock, WSD GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI NEPTUNE regional observatory system design SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc AB A team from the University of Washington (UW), the Woods Hole Oceanographic Institute (WHOI), the Monterey Bay Aquarium Research Institute (MBARI), the Jet Propulsion Laboratory (JPL), and the Institute for Pacific Ocean Science and Technology (EPOST) of Canada is jointly developing the North East Pacific Time-series Underwater Networked Experiment (NEPTUNE). NEPTUNE is being designed as a long-lived, highly reliable underwater observatory. Its basic intent is to Instrument the Juan de Fuca tectonic plate, which lies just off the coasts of Washington, Oregon, and British Columbia. NEPTUNE will use standard telecommunication fiber optic cable to provide a communication and power infrastructure. A highspeed data link (up to 1 Gb/second) and high power (at least 5 kW/node) will be available at 30 nodes spaced at approximately 100-km intervals over the tectonic plate. Each node will act as a local relay point for scientific instruments and experiments that will be deployed on the sea floor and in the water column above it. The installation of such instruments will be on a "plug and play" basis, which will allow for expansion of capability as new Instruments are developed and instruments that need repair or have completed their experiments are removed. The scientific investigations enabled by the NEPTUNE observatory are very diverse. This paper presents the current design of the observatory, Including descriptions of the key subsystems. Innovative approaches are being developed to provide high power, broadband communications, data archiving, and accurate timing and control. The methodology for ensuring the reliability and affordability of the observatory is discussed. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Rodgers, DH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. OI Kirkham, Harold/0000-0003-2893-7586 NR 13 TC 1 Z9 2 U1 0 U2 1 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 1356 EP 1365 PG 10 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800210 ER PT B AU Kirkham, H Howe, BM Vorperian, V Bowerman, P AF Kirkham, H Howe, BM Vorperian, V Bowerman, P GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI The design of the NEPTUNE power system SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc AB The proposed NEPTUNE observatory will include about 30 locations on the Juan de Fuca plate where scientific instruments can be connected for communication and power. The NEPTUNE power system is required to make available at each location the largest amount of power possible, using conventional submarine telecommunications cable. The power delivery system is based on the use of a standard cable, but it is used in an interconnected network in order to maximize both reliability and power level. The cable will be energized with medium voltage similar to10 kV dc and have parallel loads, a combination that has never been built before as an interconnected network. During normal operation, it is calculated that a power level of over 5 M can be delivered to each of the 30 nodes. Should it be needed, as much as 40 M can be delivered to each of 3 nodes on the far west of the network, 500 km from shore, provided the power on all the other nodes is reduced to I M These power levels and distances are considerably greater than has been achieved in previous undersea observatories. The design of the sub-sea node is based on the use of grouped switching mode power supplies with series-connected inputs and parallel connected low voltage outputs. The ocean is used as a return path. Consideration of the reliability of the system plays an important role in the design of the power system. A scheme of protective relaying will enable the delivery system to continue operation even with faults in part of the network. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kirkham, H (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. OI Kirkham, Harold/0000-0003-2893-7586; Howe, Bruce/0000-0001-5711-5253 NR 4 TC 2 Z9 2 U1 0 U2 1 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 1374 EP 1380 PG 7 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800212 ER PT B AU Seki, MP Bidigare, RR Lumpkin, R Polovina, JJ Kobayashi, DR Flament, P Foley, DG AF Seki, MP Bidigare, RR Lumpkin, R Polovina, JJ Kobayashi, DR Flament, P Foley, DG GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Mesoscale cyclonic eddies and pelagic fisheries in Hawaiian waters SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc ID EDDY; PACIFIC; IMAGERY; SEA AB The combination of prevailing northeasterly tradewinds and island topography result in the formation of vigorous, westward propagating cyclonic eddies in the lee of the Hawaiian Islands on time scales of 50-70 days. These mesoscale (similar to10(2) km) features are nowhere more conspicuous or spin up more frequently than in the Alenuihaha Channel between the islands of Maui and the Big Island of Hawaii. Like other open-ocean eddies, their biological impact can be significant, although Hawaii's open-ocean, wind driven features dynamically contrast the well-studied cold core current-generated eddies such as those that spin off the Gulf Stream or the Kuroshio. These latter features characteristically trap or isolate an adjacent water mass retaining its developed floristic composition. Cyclonic eddies in subtropical waters such as around Hawaii vertically displace the underlying nutricline into the overlying, nutrient-deplete euphotic zone creating localized biologically enhanced patches. Recent direct high-resolution horizontal and vertical observations of these vortices made from satellite and shipboard platforms provide new perspectives on biological enhancement within open-ocean cyclonic eddies and are presented here. These localized regions of high productivity may lead to aggregation and development of a forage base for higher trophic levels. How eddies may directly influence pelagic fish distribution are examined from recreational and commercial fish catch data coinciding with the presence of eddies. We highlight the 1995 Hawaii International Billfish Tournament in which a cyclonic eddy dominated the ocean conditions during the weeklong event and appeared to be the principle factor influencing fish availability. On the tournament grounds, well-mixed surface layers and strong current flows induced by the eddy's presence characterized the inshore waters where the highest catches of the prized Pacific blue marlin (Makaira mazara) occurred, suggesting direct (e.g., physiological limitations) and/or indirect (e.g., prey availability) biological responses of blue marlin to the prevailing environment. C1 NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. RP Seki, MP (reprint author), NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, 2570 Dole St, Honolulu, HI 96822 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 1590 EP 1594 PG 5 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800247 ER PT B AU Kobayashi, DR Polovina, JJ AF Kobayashi, DR Polovina, JJ GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Evaluation of mitigation measures for sea turtle take reduction in the Hawaii-based longline fishery SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc AB Computer simulation was used to evaluate mitigation measures for sea turtle take reduction In the Hawaii-based longline fishery. Federal logbook and observer data were merged with high-resolution environmental data to produce generalized additive models of sea turtle take. Various types of seasonal and spatial closures were evaluated as well as possible fishing gear modifications. These results led to the formal adoption of a multifaceted management policy consisting of a seasonal spatial closure of the fishery south of 15degreesN during April and May, combined with a gear restriction to prohibit swordfish style fishing in the upper surface layers for the entire fishery. C1 NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. RP Kobayashi, DR (reprint author), NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, 2570 Dole St, Honolulu, HI 96822 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 1595 EP 1595 PG 1 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800248 ER PT B AU Parrish, FA Pyle, RL AF Parrish, FA Pyle, RL GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Surface logistics and consumables for open-circuit and closed-circuit deep mixed-gas diving operations SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc AB A series of eight dives, four with open-circuit scuba and four with closed-circuit rebreathers were made to compare the two diving methodologies. Two criteria were considered: time requirements for topside equipment preparation, and consumption of expendables. The open-circuit divers required four times as much topside equipment preparation as the rebreather divers, consumed 17 times as much gas, and cost seven times more in expendables. These findings indicate significantly less time and an infrastructure are needed to support closed-circuit rebreather diving rather than conventional open circuit modes for deep mixed-gas work. C1 Natl Marine Fisheries Serv, Honolulu Lab, Honolulu, HI 96822 USA. RP Parrish, FA (reprint author), Natl Marine Fisheries Serv, Honolulu Lab, 2750 Dole St, Honolulu, HI 96822 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 1735 EP 1737 PG 3 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800273 ER PT B AU Colombo, OL Evans, AG AF Colombo, OL Evans, AG GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Precise, very long range marine positioning with GPS: Achieving sub-decimeter precision in a matter of minutes SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc AB In remote sensing over large areas with interferometric sonar, etc., that require high precision GPS geolocation, it is often desirable to achieve such precision in a short time. A technique for speeding up the convergence of the kinematic GPS navigation filter over long baselines has been tested. A buoy at sea has been positioned relative to base stations many hundreds of kilometers away. Sub-decimeter accuracy has been achieved in a few minutes, even when simultaneously relaxing the broadcast ephemeris to improve results. This fast convergence is commonplace in short-range surveys, when the vehicle is within 20 kin of a base station, so it is possible to fix the carrier phase ambiguities to an exact number of cycles. But if a ship is operating in the high seas, achieving the same accuracy requires acquiring data for close to an hour, if carrier phase biases are "floated" in the usual way. In the method tested, the gradual change in mean sea level (after waves are filtered out) is used as a constraint to the solution. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Colombo, OL (reprint author), NASA, Goddard Space Flight Ctr, Code 926, Greenbelt, MD 20771 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 1794 EP 1799 PG 6 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800283 ER PT B AU Lane, AL Carsey, FD French, GD French, LC Behar, A Engelhardt, H AF Lane, AL Carsey, FD French, GD French, LC Behar, A Engelhardt, H GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Development of extreme environment systems for seeking out extremophiles SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc ID ICE; ANTARCTICA C1 CALTECH, Jet Prop Lab, Observat Instruments Div, Pasadena, CA 91109 USA. RP Lane, AL (reprint author), CALTECH, Jet Prop Lab, Observat Instruments Div, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 2036 EP 2042 PG 7 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800323 ER PT B AU Stokes, TL Dunn, DA AF Stokes, TL Dunn, DA GP MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY MARINE TECHNOLOGY SOCIETY TI Acoustic and physical property correlation of marine sediments from the Texas-Louisiana continental shelf SO OCEANS 2001 MTS/IEEE: AN OCEAN ODYSSEY, VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Annual Conference of the Marine-Technology-Society CY NOV 05-08, 2001 CL HONOLULU, HI SP Marine Technol Soc, IEEE, OES, Minerals, Met & Mat Soc, Soc Explorat Geophysicists, Amer Geophys Union, Womens Aquat Network, Coasts, Oceans, Ports & Rivers Inst, Amer Meteorol Soc, Oceanog Soc AB Analysis of 212 samples from 23 gravity cores obtained on the Texas-Louisiana continental shelf shows that nearshore sediments in the southwestern part of the study area, closest to Corpus Christi, are a mixture of sand-silt-clay and silty clay (using the Shepard, 1954, classification), with clay percentages increasing farther from shore. Deeper-water clays have the lowest sound velocities (1413-1519 m/s), lowest dry densities (2.61-2.65 g/cm(3)), highest porosities (70-80%), and slightly higher calcium carbonate contents (0-5% to 5-10%). Sediments in the northeastern part of the study area, off east Texas and southwest Louisiana, are dominantly composed of sand-silt-clay and clayey sand. These cores have the highest sound velocities (1526-1704 m/s), highest dry densities (2.66-2.74 g/cm(3)), lowest porosities (36-67%), and generally lower calcium carbonate content (0-5%) than cores from the southwestern shelf. A linear correlation exists between acoustic and certain physical properties: an increase in mean grain size (smaller phi numbers), decreased clay content, and lower porosity produces an increase in sound velocity. Sand content and bulk grain density increase as sound velocity increases. No correlation was found between calcium carbonate content and sound velocity. C1 USN, Oceanog Off, Ocean Anal Branch, Stennis Space Ctr, Stennis Space Ctr, MS 39522 USA. RP Stokes, TL (reprint author), USN, Oceanog Off, Ocean Anal Branch, Stennis Space Ctr, Stennis Space Ctr, MS 39522 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-28-9 PY 2001 BP 2624 EP 2633 PG 10 WC Engineering, Marine; Engineering, Ocean; Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Oceanography SC Engineering; Geology; Oceanography GA BV22H UT WOS:000178200800419 ER PT S AU Sheth, RK AF Sheth, RK BE Fry, JN Buchler, JR Kandrup, H TI A random walk through models of nonlinear clustering SO ONSET OF NONLINEARITY IN COSMOLOGY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT 15th Florida Workshop in Nonlinear Astronomy and Physics: Onset of Nonlinearity in Cosmology CY FEB 17-19, 2000 CL GAINESVILLE, FLORIDA SP Dept Phys & Astronom, Coll Liberal Arts & Sci, Univ Florida, Off Res & Grad DE clusters; cosmology; dark matter; theory ID DARK-MATTER HALOES; COSMOLOGICAL PERTURBATION-THEORY; STATISTICS; PEAKS AB A few simple models of the mass function of collapsed objects are presented. The emphasis is on apparently unrelated models which end up giving the same answer for the number density and merger histories of virialized clumps. Models of the spatial distribution of the clumps and how they can be used to model the spatial distribution of the mass are briefly discussed. C1 NASA, Fermilab, Astrophys Grp, Batavia, IL 60510 USA. RP Sheth, RK (reprint author), NASA, Fermilab, Astrophys Grp, MS209,POB 500, Batavia, IL 60510 USA. NR 22 TC 5 Z9 5 U1 0 U2 2 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-324-6 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 2001 VL 927 BP 1 EP 12 PG 12 WC Astronomy & Astrophysics; Multidisciplinary Sciences SC Astronomy & Astrophysics; Science & Technology - Other Topics GA BT10S UT WOS:000171969300001 PM 11411147 ER PT S AU Chapman, B Patil, A Prabhakar, A AF Chapman, B Patil, A Prabhakar, A BE Eigenmann, R TI Performance oriented programming for NUMA architectures SO OPENMP SHARED MEMORY PARALLEL PROGRAMMING, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT Internation Workshop on OpenMp Applications and Tools (WOMPAT 2001) CY JUL 30-31, 2001 CL W LAFAYETTE, INDIANA SP OpenMP Architecture Review Board DE shared memory parallelism; parallel programming models; OpenMP; ccNUMA Architectures; restructuring; data locality; data distribution; Software Distributed Shared Memory AB OpenMP is emerging as a viable high-level programming model for shared memory parallel systems. Although it has also been implemented on ccNUMA architectures, it is hard to obtain high performance on such systems, particularly when large numbers of threads are involved. Moreover, it is applicable to NUMA machines only if a software DSM system is present. In this paper, we discuss: various ways in which OpenMP may be used on ccNUMA and NUMA architectures, and evaluate several programming styles on the SGI Origin 2000, and on TreadMarks, a Software Distributed Shared Memory System from Rice University. These results have encouraged us to begin work on a compiler that accepts an extended OpenMP and translates such code to an equivalent version that provides superior performance on both of these platforms. C1 Univ Houston, Dept Comp Sci, Houston, TX 77204 USA. NASA, Langley Res Ctr, ICASE, Hampton, VA 23665 USA. RP Chapman, B (reprint author), Univ Houston, Dept Comp Sci, Houston, TX 77204 USA. NR 16 TC 5 Z9 5 U1 1 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-42346-X J9 LECT NOTES COMPUT SC PY 2001 VL 2104 BP 137 EP 154 PG 18 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BT97N UT WOS:000174608200013 ER PT S AU Ansari, RR Giblin, F King, JF Lambert, LM AF Ansari, RR Giblin, F King, JF Lambert, LM BE Manns, F Soderberg, PG Ho, A TI Non-invasive and remote detection of cataracts during space exploration with dynamic light scattering SO OPHTHALMIC TECHNOLOGIES XI SE Proceedings of SPIE LA English DT Proceedings Paper CT 11th Conference on Ophthalmic Technologies XI CY JAN 20-21, 2001 CL SAN JOSE, CA SP SPIE ID PROTEIN DIFFUSIVITY; RABBIT; LENS; PROBE AB Outer space is filled with high-energy ionizing radiation. Continuous radiation exposure or slight increase (e.g., due to flares) in it can be hazardous to astronaut health. Therefore cataractogenesis is a possible risk factor. In this paper we apply the sensitive technique of dynamic light scattering to investigate the simulated effects of X-ray exposure to the ocular tissue of non-human animals. An internet web based system integrates photon correlation data and controls the hardware for animal monitoring at a remote site in real time. C1 NASA Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Cleveland, OH 44135 USA. RP NASA Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Mail Stop 333-1,21000 Brookpark Rd, Cleveland, OH 44135 USA. EM rafat.r.ansari@grc.nasa.gov; giblin@oakland.edu NR 17 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3923-1 J9 PROC SPIE PY 2001 VL 4245 BP 129 EP 134 DI 10.1117/12.429264 PG 6 WC Engineering, Biomedical; Ophthalmology; Optics SC Engineering; Ophthalmology; Optics GA BS70A UT WOS:000170898000015 ER PT S AU Ansari, RR Rovati, L Sebag, J AF Ansari, RR Rovati, L Sebag, J BE Manns, F Soderberg, PG Ho, A TI Celestial and terrestrial tele-ophthalmology: A health monitoring helmet for astronaut/cosmonaut and general public use SO OPHTHALMIC TECHNOLOGIES XI SE Proceedings of SPIE LA English DT Proceedings Paper CT 11th Conference on Ophthalmic Technologies XI CY JAN 20-21, 2001 CL SAN JOSE, CA SP SPIE ID DIABETIC-RETINOPATHY; RAMAN-SPECTROSCOPY; AUTOFLUORESCENCE AB A goggles-like head-mounted device equipped with several non-invasive techniques for quantitative medical evaluation of the eye, skin, and brain is envisioned for monitoring the health of astronauts and cosmonauts during long-term space travel and exploration. Real-time non-invasive evaluation of the different structures within these organs will provide indices. of the health of these organs, as well as the entire body. The techniques such as dynamic light scattering (for the early detection of cataracts to evaluate effects of cosmic radiation), corneal autofluorescence (to assess extracellular matrix biology (e.g., diabetes), optical polarization (of aqueous fluid to evaluate serum chemistry), laser Doppler velocimetry (of retinal, optic nerve, and choroidal blood flow to assess ocular as well as central nervous system blood flow), reflectometry/oximetry (for oxygen metabolism), optical coherence tomography (for retinal microstructure), and possibly scanning laser technology for intraocular imaging and scanning will be integrated into this compact device. Skin sensors will also be mounted on the portion of the device in contact with the periocular tissues. This will enable monitoring of body temperature, electrolyte status and EEG. This device will monitor astronaut health during long-duration space travel by detecting aberrations from pre-established "norms", enabling prompt initiation of early preventative/curative therapy. C1 NASA, Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Cleveland, OH 44135 USA. RP NASA, Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Mail Stop 333-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM rafat.r.ansari@grc.nasa.gov; rovati@bsing.ing.unibs.it; jsebag@pol.net RI Rovati, Luigi/K-3445-2015; OI Rovati, Luigi/0000-0002-1743-3043; Sebag, J/0000-0001-8648-5747 NR 32 TC 2 Z9 2 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3923-1 J9 PROC SPIE PY 2001 VL 4245 BP 177 EP 185 DI 10.1117/12.429269 PG 9 WC Engineering, Biomedical; Ophthalmology; Optics SC Engineering; Ophthalmology; Optics GA BS70A UT WOS:000170898000021 ER PT S AU Flanegan, M AF Flanegan, M BE Digonnet, MJF Gebizlioglu, OS Greenwell, RA Horwitz, DN Paul, DK TI Geoscience Laser Altimeter System (GLAS) spaceflight instrument fiber optic system SO OPTICAL DEVICES FOR FIBER COMMUNICATION II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Devices for Fiber Communication II CY NOV 06-08, 2000 CL BOSTON, MA SP SPIE DE spaceflight fiber optics; GLAS; IceSat AB GLAS is a satellite laser altimeter designed to measure ice-sheet topography and cloud and atmospheric properties. The onboard laser is an Nd:YAG with doubler, emitting 1064 nm and 532 nm light. The reflected light from the Earth and atmosphere is collected by a telescope and analyzed to produce the altimetry results. Fiber optics are used to route timing and calibration signals within the instrument as well as to provide calibrated delays. The fiber optic system includes free space to fiber coupling optics, cables and connectors, diode laser and LED fiber pigtails and a 2 kilometer fiber optic delay line. Since these signals are received and processed as analog values, it is necessary to preserve the magnitude, timing and pulse shape as much as possible in the thermal, mechanical and radiation environment of space. This is in contrast to many onboard fiber optic systems which are used for digital communication and can accept wide variations in these parameters as long as the thresholds for accurate detection of a bit aren't exceeded. The requirements include a stability of up to 1% in signal magnitude and 30 ps timing stability in the tinting signals and fiber optic delay line over the whole mission, including all environmental effects. Meeting these requirements with the spacecraft resources available has proven challenging. Fiber optic components have been chosen and tested to accomplish this as best as possible. The system design, components selected and testing performed will be discussed in this paper. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Flanegan, M (reprint author), NASA, Goddard Space Flight Ctr, Code 554, Greenbelt, MD 20771 USA. NR 4 TC 0 Z9 0 U1 1 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3881-2 J9 P SOC PHOTO-OPT INS PY 2001 VL 4216 BP 199 EP 205 DI 10.1117/12.414116 PG 7 WC Optics; Telecommunications SC Optics; Telecommunications GA BS17D UT WOS:000168951200024 ER PT S AU Ott, MN Friedberg, P AF Ott, MN Friedberg, P BE Digonnet, MJF Gebizlioglu, OS Greenwell, RA Horwitz, DN Paul, DK TI Technology validation of optical fiber cables for space flight environments SO OPTICAL DEVICES FOR FIBER COMMUNICATION II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Devices for Fiber Communication II CY NOV 06-08, 2000 CL BOSTON, MA SP SPIE DE fiber optic; radiation effects; thermal effects; communications; harsh environments; multimode; testing; cable; preconditioning. AB Periodically, commercially available (commercial off the shelf, COTS) optical fiber cable assemblies are characterized for space flight usage under the NASA Electronic Parts and Packaging Program (NEPP). The purpose of this is to provide a family of optical fiber cable options to a variety of different harsh environments typical to space flight missions. The optical fiber cables under test are evaluated to bring out known failure mechanisms that are expected to occur during a typical mission. The tests used to characterize COTS cables include: vacuum exposure, thermal cycling and radiation exposure. Presented hen are the results of the testing conducted at NASA Goddard Space Flight Center on COTS optical fiber cables over this past year. Several optical fiber cables were characterized for their thermal stability both during and after thermal cycling. The results show how much preconditioning is necessary for a variety of available cables to remain thermally stable in a space flight environment. Several optical fibers of dimensions 100/140/172 microns were characterized for their radiation effects at -125 degreesC using the dose rate requirements of International Space Station. One optical fiber cable in particular was tested for outgassing to verify whether an acrylate coated fiber could be used in a space flight optical cable configuration. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ott, MN (reprint author), NASA, Goddard Space Flight Ctr, Code 562, Greenbelt, MD 20771 USA. NR 9 TC 6 Z9 6 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3881-2 J9 P SOC PHOTO-OPT INS PY 2001 VL 4216 BP 206 EP 217 DI 10.1117/12.414117 PG 12 WC Optics; Telecommunications SC Optics; Telecommunications GA BS17D UT WOS:000168951200025 ER PT S AU Fleming, GA Bartram, SM Waszak, MR Jenkins, LN AF Fleming, GA Bartram, SM Waszak, MR Jenkins, LN BE Mercer, CR Cha, SS Shen, G TI Projection moire interferometry measurements of micro air vehicle wings SO OPTICAL DIAGNOSTICS FOR FLUIDS SOLIDS AND COMBUSTION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostics for Fluids, Solids, and Combustion CY JUL 31-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE DE projection moire interferometry; PMI; micro air vehicle; MAV; aeroelastic; wing deformation AB Projection Moire Interferometry (PMI) has been used to measure the structural deformation of micro air vehicle (MAV) wings during a series of wind tunnel tests. The MAV wings had a highly flexible wing structure. generically reminiscent of a bat's wing, which resulted in significant changes in wing shape as a function of MAV angle-of-attack and simulated flight speed. This flow-adaptable wing deformation is thought to provide enhanced vehicle stability and wind gust alleviation compared to rigid wing designs. Investigation of the potential aerodynamic benefits of a flexible MAV wing required measurement of the wing shape under aerodynamic loads. PMI was used to quantify the aerodynamically induced changes in wing shape for three MAV wings having different structural designs and stiffness characteristics. This paper describes the PMI technique. its application to MAV testing. and presents a portion of the PMI data acquired for the three different MAV wings tested. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Fleming, GA (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 12 TC 3 Z9 3 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4162-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4448 BP 90 EP 101 DI 10.1117/12.449365 PG 12 WC Optics SC Optics GA BT74R UT WOS:000173939100011 ER PT S AU Graves, SS Burner, AW AF Graves, SS Burner, AW BE Mercer, CR Cha, SS Shen, G TI Development of an intelligent videogrammetric wind tunnel measurement system SO OPTICAL DIAGNOSTICS FOR FLUIDS SOLIDS AND COMBUSTION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostics for Fluids, Solids, and Combustion CY JUL 31-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE DE videogrammetry; photogrammetry; model deformation; model attitude; pattern recognition; computer vision; fuzzy image processing ID FACE AB A videogrammetric technique developed at NASA Langley Research Center has been used at five NASA facilities at the Langley and Ames Research Centers for deformation measurements on a number of sting mounted and semispan models. These include high-speed research and transport models tested over a wide range of aerodynamic conditions including subsonic, transonic, and supersonic regimes. The technique. based on digital photogrammetry. has been used to measure model attitude, deformation. and sting bending, In addition, the technique has been used to study model injection rate effects and to calibrate and validate methods for predicting static aeroelastic deformations of wind tunnel models. An effort is currently underway to develop an intelligent videogrammetric measurement system that will be both useful and usable in large production wind tunnels while providing accurate data in a robust and timely manner. Designed to encode a higher degree of knowledge through computer vision, the system features advanced pattern recognition techniques to improve automated location and identification of targets placed on the wind tunnel model to be used for aerodynamic measurements such as attitude and deformation. This paper will describe the development and strategy of the new intelligent system that was used in a recent test at a large transonic wind tunnel. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Graves, SS (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 18 TC 8 Z9 8 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4162-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4448 BP 120 EP 131 DI 10.1117/12.449368 PG 12 WC Optics SC Optics GA BT74R UT WOS:000173939100014 ER PT S AU Decker, AJ AF Decker, AJ BE Mercer, CR Cha, SS Shen, G TI Optimization of training sets for neural-net processing of characteristic patterns from vibrating solids SO OPTICAL DIAGNOSTICS FOR FLUIDS SOLIDS AND COMBUSTION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostics for Fluids, Solids, and Combustion CY JUL 31-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE DE holography; neural networks; characteristic patterns ID NETWORKS AB Artificial neural networks have been used for a number of years to process holography-generated characteristic patterns of vibrating structures. This technology depends critically on the selection and the conditioning of the training sets. A scaling operation called folding is discussed for conditioning training sets optimally for training feed-forward neural networks to process characteristic fringe patterns. Folding allows feed-forward nets to be trained easily to detect damage-induced vibration-displacement-distribution changes as small as 10 nanometers. A specific application to aerospace of neural-net processing of characteristic patterns is presented to motivate the conditioning and optimization effort. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Decker, AJ (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4162-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4448 BP 209 EP 217 DI 10.1117/12.449379 PG 9 WC Optics SC Optics GA BT74R UT WOS:000173939100023 ER PT S AU Stahl, HP AF Stahl, HP BE Stahl, HP TI Development of lightweight mirror technology for the Next Generation Space Telescope SO OPTICAL MANUFACTURING AND TESTING IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Optical Manufacturing and Testing IV Conference CY JUL 31-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE AB In 2009, NASA plans to launch the Next Generation Space Telescope (NGST) to the L2 point, 1.5 million kilometers from Earth. With a 6-meter diameter mirror, NGST is a successor to the Hubble Space Telescope with 5 times the collecting aperture. As part of NASA's Origins Program, the ten-year observing mission will search for the "first light" of the universe. NGST will provide astronomers with unparalleled light collection, mid-infrared sensitivity, spatial resolution and field of view. Mirror technology is critical to the system's success. The hard part is solving the problem of how to launch a 6m, 600 kg, mirror into space on a 4-meter diameter rocket. Additionally, high performance is expected at operating temperatures of 50K. This paper reviews the mirror requirements and development efforts. C1 NASA, George C Marshall Space Flight Ctr, Space Opt Mfg Technol Ctr, Huntsville, AL 35812 USA. RP Stahl, HP (reprint author), NASA, George C Marshall Space Flight Ctr, Space Opt Mfg Technol Ctr, Huntsville, AL 35812 USA. NR 2 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4165-1 J9 P SOC PHOTO-OPT INS PY 2001 VL 4451 BP 1 EP 4 DI 10.1117/12.453604 PG 4 WC Optics SC Optics GA BT91N UT WOS:000174430600001 ER PT S AU Waluschka, E Arsenovic, P Content, D Saha, T Strojny, C Wright, G Fleetwood, C AF Waluschka, E Arsenovic, P Content, D Saha, T Strojny, C Wright, G Fleetwood, C BE Stahl, HP TI Constellation-X cylinder figuring and polishing studies SO OPTICAL MANUFACTURING AND TESTING IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Optical Manufacturing and Testing IV Conference CY JUL 31-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE DE Constellation-X; x-ray; optics; astronomy; fabrication AB In support of Goddard Space Flight Center's (GSFC) Constellation-X mandrel manufacturing effort, a series of fabrication experiments are being performed to determine a best approach, and to supply the project with precision mandrels. Currently, polishing immediately after diamond turning produces a RMS surface roughness of 0.3 nm, on an electroless nickel-plated aluminum mandrel. Studies currently under way will incorporate an abrasive-figuring step to be followed by this polishing operation. The current diamond turning, figuring and polishing procedures will be described and the results presented. C1 NASA, Goddard Space Flight Ctr 551, Greenbelt, MD 20771 USA. RP Waluschka, E (reprint author), NASA, Goddard Space Flight Ctr 551, Greenbelt, MD 20771 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4165-1 J9 P SOC PHOTO-OPT INS PY 2001 VL 4451 BP 233 EP 241 DI 10.1117/12.453621 PG 9 WC Optics SC Optics GA BT91N UT WOS:000174430600027 ER PT S AU Gubarev, M Kester, T Takacs, PZ AF Gubarev, M Kester, T Takacs, PZ BE Stahl, HP TI Calibration of a vertical-scan long trace profiler at MSFC SO OPTICAL MANUFACTURING AND TESTING IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Optical Manufacturing and Testing IV Conference CY JUL 31-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE DE long trace profiler; calibration; accuracy; systematic error ID MIRRORS AB The long trace profiler (LTP) is the instrument of choice for the surface figure measurement of grazing incidence mirrors. The modification of conventional LTP, the vertical-scan LTP, capable of measuring the surface figure of replicated shell mirrors is now in operation at Marshall Space Flight Center. A few sources of systematic error for vertical scan LTP are discussed. Status of systematic error reduction is reported. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Gubarev, M (reprint author), NASA, George C Marshall Space Flight Ctr, SD70, Huntsville, AL 35812 USA. NR 5 TC 11 Z9 11 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4165-1 J9 P SOC PHOTO-OPT INS PY 2001 VL 4451 BP 333 EP 339 DI 10.1117/12.453648 PG 7 WC Optics SC Optics GA BT91N UT WOS:000174430600038 ER PT S AU Chao, TH Zhou, HY Reyes, G AF Chao, TH Zhou, HY Reyes, G BE Casasent, DP Chao, TH TI Grayscale optical correlator for real-time onboard ATR SO OPTICAL PATTERN RECOGNITION XII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Pattern Recognition XII CY APR 19, 2001 CL ORLANDO, FL SP SPIE DE grayscale optical correlator; automatic target recognition; optical MACH correlation filter; miniature packaging ID CORRELATION FILTERS AB Jet Propulsion Laboratory (JPL) has been developing grayscale optical correlator (GOC) for a variety of automatic target recognition (ATR) applications [1-5]. As reported in previous papers, a 128 x 128 camcorder-sized GOC [1-3] has been demonstrated for real-time field ATR demos. In this paper, we will report the recent development of a prototype 512 x 512 GOC utilizing a new miniature ferroelectric liquid crystal spatial light modulator (FLCSLM) with a 7-mum pixel pitch. Experimental demonstration of ATR applications using this new GOC will be presented. The potential of developing a matchbox-sized GOC will also be discussed. A new application of synthesizing new complex-valued correlation filters using this real-axis 512 x 512 SLM will also be included. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Chao, TH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 2 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4082-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4387 BP 10 EP 15 DI 10.1117/12.421138 PG 6 WC Computer Science, Artificial Intelligence; Optics SC Computer Science; Optics GA BS37J UT WOS:000169645300002 ER PT S AU Juday, RD Rollins, JM Monroe, SE AF Juday, RD Rollins, JM Monroe, SE BE Casasent, DP Chao, TH TI SLM operating curves for statistical pattern recognition metrics SO OPTICAL PATTERN RECOGNITION XII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Pattern Recognition XII CY APR 19, 2001 CL ORLANDO, FL SP SPIE DE optical correlator; optimal filters; optical pattern recognition ID FILTERS AB We show how the signal to noise ratio distributes ideally in the complex plane of filter values, and we show how it is captured in its representation on the restricted set of values the filter SLM is able to realize. The ability to take strong advantage of a large dynamic range of filter magnitude is apparent. Further work will extend this concept to other metrics of optical correlator performance, including statistical pattern recognition (PR) criterion functions such as Bayes' error, ROC (receiver operating characteristic) curve's area, and Fisher ratio. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Juday, RD (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4082-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4387 BP 27 EP 40 DI 10.1117/12.421149 PG 14 WC Computer Science, Artificial Intelligence; Optics SC Computer Science; Optics GA BS37J UT WOS:000169645300004 ER PT S AU Chao, TH Reyes, G Zhou, HY AF Chao, TH Reyes, G Zhou, HY BE Casasent, DP Chao, TH TI Compact holographic memory and its application to optical pattern recognition SO OPTICAL PATTERN RECOGNITION XII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Pattern Recognition XII CY APR 19, 2001 CL ORLANDO, FL SP SPIE DE holographic memory; electro-optic beam steering; grayscale optical correlator; pattern recognition MACH correlation filter ID CORRELATOR AB JPL is developing a high-density, nonvolatile Compact Holographic Data Storage (CHDS) system to enable large-capacity, high-speed, low power consumption, and read/write of data for commercial and space applications. This CHDS system consists of laser diodes, photorefractive crystal, spatial light modulator, photodetector array, and I/O electronic interface. In operation pages of information would be recorded and retrieved with random access and high-speed. In this paper, recent technology progress in developing this CHDS at JPL will be presented. The recent applications of the CHDS to optical pattern recognition, as a high-density, high transfer rate memory bank will also be discussed. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Chao, TH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4082-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4387 BP 60 EP 67 DI 10.1117/12.421152 PG 8 WC Computer Science, Artificial Intelligence; Optics SC Computer Science; Optics GA BS37J UT WOS:000169645300007 ER PT S AU Habib, S AF Habib, S BE Sasano, Y Wang, J Hayasaka, T TI Technology thrusts for future earth science applications SO OPTICAL REMOTE SENSING OF THE ATMOSPHERE AND CLOUDS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Remote Sensing of the Atmosphere and Clouds II CY OCT 09-12, 2000 CL SENDAI, JAPAN SP SPIE, Natl Space Dev Agcy Japan, Tohoku Inst Technol, NASA Langley Res Ctr, Natl Polar Orbiting Operat Environm Satellite Syst, Integrated Program Off, TRW AB This paper presents NASA's recent direction to invest in the critical science instrument and platform technologies in order to realize more reliable, frequent and versatile missions for future Earth Science measurements. Historically: NASA's Earth Science Enterprise has developed and flown science missions that have been large in size, mass and volume. These missions have taken much longer to implement due to technology development time, and have carried a large suite of instruments on a large spacecraft. NASA is now facing an era where the budget for the future years is more or less flat and the possibility for any major new start does not vividly appear on the horizon. Unfortunately, the scientific measurement needs for remote sensing have not shrunk to commensurate with the budget constraints. In fact, the challenges and scientific appetite in search of answers to a score of outstanding questions have been gradually expanding. With these factors in mind, for the last three years NASA has been changing its focus to concentrate on how to take advantage of smaller missions by relying on industry, and minimizing the overall mission life cycle by developing technologies that are independent of the mission implementation cycle. The major redirection of early investment in the critical technologies should eventually have its rewards and significantly reduce the mission development period. Needless to say, in the long run this approach should save money, minimize risk, promote or encourage partnering, allow for a rapid response to measurement needs, and enable frequent missions making a wider variety of earth science measurements. This paper gives an overview of same of the identified crucial technologies and their intended applications for meeting the future Earth Science challenges. C1 NASA, Goddard Space Flight Ctr, Earth Sci Directorate, Greenbelt, MD 20771 USA. RP Habib, S (reprint author), NASA, Goddard Space Flight Ctr, Earth Sci Directorate, Greenbelt, MD 20771 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3803-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4150 BP 124 EP 137 DI 10.1117/12.416951 PG 2 WC Meteorology & Atmospheric Sciences; Remote Sensing; Optics SC Meteorology & Atmospheric Sciences; Remote Sensing; Optics GA BS18S UT WOS:000169001200014 ER PT S AU Kawamoto, K Nakajima, T AF Kawamoto, K Nakajima, T BE Sasano, Y Wang, J Hayasaka, T TI Global cloud property analysis rasing satellite remote sensing SO OPTICAL REMOTE SENSING OF THE ATMOSPHERE AND CLOUDS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Remote Sensing of the Atmosphere and Clouds II CY OCT 09-12, 2000 CL SENDAI, JAPAN SP SPIE, Natl Space Dev Agcy Japan, Tohoku Inst Technol, NASA Langley Res Ctr, Natl Polar Orbiting Operat Environm Satellite Syst, Integrated Program Off, TRW DE cloud microphysics; satellite remote sensing; climate ID SOLAR-RADIATION MEASUREMENTS; EFFECTIVE PARTICLE RADIUS; OPTICAL-THICKNESS; SCATTERING; RADIOMETER; FIRE AB Clouds are recognized as an important factor in the earth's climate system. In particular, the optical and microphysical properties such as the optical thickness and droplet size are needed for understanding cloud processes. Therefore Kawamoto et al. (2000) developed a retrieval algorithm for the cloud optical thickness and effective particle radius on a global scale. In this work, we retrieve the cloud liquid water path and columnar cloud droplet number density as by-products, in addition to the cloud optical thickness and effective particle radius. The annual mean characteristics of these quantities on a global scale are described. C1 Virginia Polytech Inst & State Univ, NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Kawamoto, K (reprint author), Virginia Polytech Inst & State Univ, NASA, Langley Res Ctr, MS 420, Hampton, VA 23681 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3803-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4150 BP 200 EP 207 DI 10.1117/12.416958 PG 4 WC Meteorology & Atmospheric Sciences; Remote Sensing; Optics SC Meteorology & Atmospheric Sciences; Remote Sensing; Optics GA BS18S UT WOS:000169001200021 ER PT S AU Larar, AM Smith, WL Zhou, DK Browell, EV Ferrare, RA Revercombe, HE Tobin, DC AF Larar, AM Smith, WL Zhou, DK Browell, EV Ferrare, RA Revercombe, HE Tobin, DC BE Larar, AM Mlynczak, MG TI Spectral radiance validation studies using NAST-I and other independent measurement systems SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr DE remote sensing; spectrometry; infrared radiation; Fourier transform spectrometer; interferometry AB The National Polar-orbiting Operational Environmental Satellite System (NPOESS) Airborne Sounding Testbed-Interferometer (NAST-I), is the infrared component of a suite of airborne infrared and microwave spectrometers, developed for the Integrated Program Office (IPO), that has been flying on high-altitude aircraft as part of the risk reduction effort for NPOESS. It is a high spectral resolution (0.25 cm(-1), unapodized) and high spatial resolution (similar to2 km, nadir) cross-track scanning (similar to 45 km swath width, at 20 km aircraft altitude) Fourier Transform Spectrometer (FTS) observing within the 3.7 - 16.1 micron spectral range. In addition to characterizing the atmospheric thermal and moisture structure and providing information on radiatively active trace gases (e.g. 03 & CO) during field experiments, NAST-I measurements greatly contribute toward instrument and forward model pre-launch specification optimization (i.e., for the Cross-track Infrared Sounder, CrIS, to fly on NPOESS) and will enhance post-launch calibration/validation activities for CrIS as well as for other future advanced atmospheric spaceborne sensors (e.g., the EOS AIRS, CERES, MODIS, MOPITT, & TES instruments). In this paper, we investigate some of the challenges associated with validating infrared spectral radiances obtained from remote sensing measurements and for-ward model simulations. Specifically, measured infrared spectral radiances are compared with radiance calculations performed using a Line by Line forward radiative transfer model based on nearly-coincident temperature and water vapor profiles observed with several independent in-situ, passive, and active measurement systems. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Larar, AM (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 81 EP 90 AR UNSP 4485-14 PG 10 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500009 ER PT S AU Smith, WL Zhou, DK Larar, AM AF Smith, WL Zhou, DK Larar, AM BE Larar, AM Mlynczak, MG TI Vertical profile radiation measurements - A spectroscopic tool SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr AB Airborne profiles of spectral radiances between 3.5 and 15 microns are used to derive profiles of atmospheric temperature and the concentrations of radiatively active absorbing gases. These measurements are intended for the validation of atmospheric radiative transfer physics and associated forward models as well satellite remote sensing techniques and products. Vertical profiles of upwelling spectral radiance are obtained during ascents and descents of the Proteus aircraft carrying the NPOESS Airborne Sounding Test-bed - Interferometer (NAST-I). Opaque region radiance measurements provide the vertical temperature profile while the vertical derivative of radiance with respect to Planck radiance provides the vertical distribution of spectral emissivity. Spectral regions where only a single absorbing gas is active can be used to derive the mixing ratio profile for that gas, assuming the spectroscopy (i.e., line strengths, shapes, and pressure and temperature dependencies) is accurately known for the spectral region used. For the case where the gaseous mixing ratio is either known to be well mixed (e.g., CO2) or is measured in-situ from aircraft or balloon profile observations, the accuracy of the spectroscopic parameters used for radiative transfer calculations can be validated. In this paper, results obtained from vertical profile measurements associated with four different air mass conditions are used to depict the errors associated with radiative transfer calculations within the R-branch of the 15 jam CO2 band. The airborne spectrometer observation technique illustrated here is proving to be a useful spectroscopic validation tool. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Smith, WL (reprint author), NASA, Langley Res Ctr, 21 Langley Blvd, Hampton, VA 23681 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 91 EP 98 AR UNSP 4485-15 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500010 ER PT S AU Chu, WP Veiga, RE Cisewski, MS Trepte, CR AF Chu, WP Veiga, RE Cisewski, MS Trepte, CR BE Larar, AM Mlynczak, MG TI SAGE III Meteor mission: Pre-launch preparation, post-launch operation, and initial on-orbit data SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr ID STRATOSPHERIC AEROSOL AB The Stratospheric Aerosol and Gas Experiment III (SAGE III) Meteor mission was originally scheduled for launch in the early summer of 2001. This paper will discuss the overall SAGE III/Meteor mission and provide a description of the instrument performance based on different pre-launch tests that have been performed over the last two years. Pre-launch tests include instrument radiometric throughput and calibration; wavelength calibration; polarization response, and in-atmospheric testing including sun and moon viewing. The resulting data demonstrate the capability of the instrument to provide high spectral resolution atmospheric spectral measurement in the visible to the near IR wavelength region with a high SNR. The instrument has been integrated onto the Meteor spacecraft at the NIIEM facility in Russia. Since the launch of the Meteor SAGE III has been delayed until the end of 200 1, this paper will only provide a description of the planned initial operation of the SAGE III instrument after launch. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Chu, WP (reprint author), NASA, Langley Res Ctr, MS 475, Hampton, VA 23681 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 128 EP 134 AR UNSP 4485-27 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500014 ER PT S AU Veiga, RE Wenny, BN Hansen, GM Lucker, PL Chu, WP AF Veiga, RE Wenny, BN Hansen, GM Lucker, PL Chu, WP BE Larar, AM Mlynczak, MG TI The SAGE III Test Model: Ground-based coincident measurements with the SAGE III flight instruments and field characterization measurements SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr AB Five functional UV-VIS-NIR spectrometer/telescopes were built for the Stratospheric Aerosol and Gas Experiment III (SAGE III) satellite instrument project. Three will be on satellite platforms in the early part of the decade, and a fourth, the SAGE III Test Model (TM) is functioning as a ground-based instrument. The fifth is used as a software test-bed to support Mission Operations for the space instruments. The SAGE III instrument is spatially scanning UV-VIS-NIR holographic grating spectrometer using a cooled CCD detector. This paper presents performance results from the TM instrument. The TM instrument has been used in cross calibration studies during which one of the SAGE III flight instruments directly sampled the Sun, Moon, and twilight sky from the ground. Comparisons of SNRs, and relative responsivities are presented. TM zenith twilight spectra and measurement sensitivities are presented including a comparison of its twilight radiance measurements with the MODTRAN 3.7 atmospheric radiance/transmittance model. In addition the TM results of sampling planetary and stellar spectra are presented. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Veiga, RE (reprint author), NASA, Langley Res Ctr, MS 475, Hampton, VA 23681 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 135 EP 141 AR UNSP 4485-29 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500015 ER PT S AU Mlynczak, MG Harries, JE Rizzi, R Stackhouse, PW Kratz, DP Johnson, DG Mertens, CJ Garcia, RR Soden, BJ AF Mlynczak, MG Harries, JE Rizzi, R Stackhouse, PW Kratz, DP Johnson, DG Mertens, CJ Garcia, RR Soden, BJ BE Larar, AM Mlynczak, MG TI The far-infrared: A frontier in remote sensing of Earth's climate and energy balance SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr ID RADIATION BUDGET EXPERIMENT; GENERAL-CIRCULATION MODEL; TROPOSPHERIC WATER-VAPOR; CIRRUS CLOUDS; MICHELSON INTERFEROMETER; SPECTRAL RADIANCE; FEEDBACK; SPACE AB The radiative balance of the troposphere, and hence climate, is influenced strongly by radiative cooling associated with emission of infrared radiation by water vapor, particularly at far-infrared (far-IR) wavelengths greater than 15 p,mum and extending out beyond 50 mum. Water vapor absorption and emission is principally due to the pure rotation band, which includes both line and continuum absorption. The distribution of water vapor and associated far-IR radiative forcings and feedbacks are well-recognized as major uncertainties in understanding and predicting future climate. Up to half of the outgoing longwave radiation (OLR) from the Earth occurs beyond 15.4 mum (650 cm(-1)) depending on atmospheric and surface conditions. Cirrus clouds also modulate the outgoing longwave radiation in the far-IR. However, despite this fundamental importance, far-IR emission (spectra or band-integrated) has rarely been directly measured from space, airborne, or ground-based platforms. Current and planned operational and research satellites typically observe the mid-infrared only to about 15.4 pm. In this talk we will review the role of the far-IR radiation in climate and will discuss the scientific and technical requirements for far-IR measurements of the Earth's atmosphere. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Mlynczak, MG (reprint author), NASA, Langley Res Ctr, 21 Langley Blvd, Hampton, VA 23681 USA. NR 42 TC 9 Z9 9 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 150 EP 158 AR UNSP 4485-32 DI 10.1117/12.454247 PG 9 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500017 ER PT S AU Kratz, DP AF Kratz, DP BE Larar, AM Mlynczak, MG TI High resolution modeling of the far-infrared SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr DE Earth's atmosphere; far-infrared; water vapor; monochromatic calculations ID WATER-VAPOR CONTINUUM; ATMOSPHERIC FLUXES; RADIATION CODES; CLIMATE MODELS; COOLING RATES; ABSORPTION; WINDOW; SYSTEM; CERES; EARTH AB Monochromatic calculations have been used to ascertain the far-infrared (wave numbers less than 650 cm(-1)) contribution to the thermal energy budget of the Earth's atmosphere-surface system. The results of the model calculations for clear-sky conditions have demonstrated that nearly half of the outgoing thermal energy emanates from the far-infrared. Despite the critical importance of the far-infrared, however, very few direct measurements of this spectral region have been made by satellite, aircraft, and surface instruments. Thus the present study has used the monochromatic calculations both to quantify the magnitude of the radiative impact which the infrared-active molecules have upon the absorption and emission of far-infrared energy within the atmosphere, and to focus our attention on the subintervals within the far-infrared that may provide the most useful measurements for climate studies. The results of the monochromatic calculations have illustrated the importance of the radiative effects attributed to the line and continuum features associated with the pure rotation band of water vapor. Subdividing the far-infrared into moderately "narrow" band (similar to100 to 200 cm-1) spectral regions has facilitated an analysis of the relative contributions of those spectral regions for a variety of atmospheric conditions. The results from the contribution function calculations have demonstrated that a careful selection of the far-infrared "narrow" band subintervals can prove very useful in determining both upper and lower tropospheric humidity. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Kratz, DP (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 22 TC 5 Z9 5 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 171 EP 180 AR UNSP 4485-34 PG 10 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500019 ER PT S AU Mertens, CJ AF Mertens, CJ BE Larar, AM Mlynczak, MG TI Feasibility of retrieving upper tropospheric water vapor from observations of far-infrared radiation SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE Proceedings of SPIE LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr DE infrared remote sensing; far-infrared; inverse theory; tropospheric water vapor ID CLIMATE; BUDGET AB Since the early 1970's, infrared remote sensing of water vapor has been based exclusively on observations of mid-infrared (mid-ir) emission from the strong 6.3 mum vibration-rotation band. However, the outgoing longwave radiation from Earth is dominated by emission in the far-infrared (far-ir) at wavelengths greater than 15 pin. The source of this far-ir radiation is upper tropospheric water vapor. Furthermore, there are a growing number of novel instrument concepts that propose measuring the thermal far-ir spectrum for the purpose of radiation budget sensing and climate fingerprinting. As a result. we investigate the feasibility of retrieving upper tropospheric water vapor from nadir-viewing observations of far-ir spectral emission. We find that it is possible to retrieve upper tropospheric water vapor from measurements of the far-ir spectral radiation. and that the vertical resolution can be significantly improved by combining measurements from the far-ir and mid-ir spectrum. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP NASA, Langley Res Ctr, Hampton, VA 23665 USA. EM c.j.mertens@larc.nasa.gov NR 7 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 PROC SPIE PY 2001 VL 4485 BP 191 EP 201 AR UNSP 4485-36 PG 11 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500021 ER PT S AU Johnson, DG AF Johnson, DG BE Larar, AM Mlynczak, MG TI Design of a far-infrared spectrometer for atmospheric thermal emission measurements SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr DE Fourier transform spectrometers; infrared spectroscopy; atmospheric remote sensing; atmospheric temperature; atmospheric humidity; radiative transfer AB Global measurements of far infrared emission from the upper troposphere are required to test models of cloud radiative forcing, water vapor continuum emission, and cooling rates. Spectra with adequate resolution can also be used for retrieving atmospheric temperature and humidity profiles, and yet there are few spectrally resolved measurements of outgoing longwave flux at wavelengths longer than 16 mum. It has been difficult to make measurements in the far infrared due to the need for liquid-helium cooled detectors and large optics to achieve adequate sensitivity and bandwidth. We review design considerations for infrared Fourier transform spectrometers, including the dependence of system performance on basic system parameters, and discuss the prospects for achieving useful sensitivity from a satellite platform with a lightweight spectrometer using uncooled detectors. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Johnson, DG (reprint author), NASA, Langley Res Ctr, MS 468, Hampton, VA 23681 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 220 EP 224 AR UNSP 4485-39 PG 5 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500024 ER PT S AU Content, D Arsenovic, P Kuznetsov, I Hadjimichael, T AF Content, D Arsenovic, P Kuznetsov, I Hadjimichael, T BE Larar, AM Mlynczak, MG TI Grating groove metrology and efficiency predictions from the soft x-ray to the far infrared SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr DE diffraction gratings; atomic force microscope; microinterferometer; stylus profilometer ID COUPLED-WAVE ANALYSIS; SURFACE-RELIEF GRATINGS; DIFFRACTION GRATINGS; INTEGRAL METHOD; OPTICAL SCATTEROMETRY; WAVELENGTH REGION; TM POLARIZATION; CONVERGENCE; FABRICATION; ECHELLES AB Methods for surface metrology have advanced significantly in the last few years, driven largely by the metrology needs for advanced lithographic processes. This paper applies recently developed metrology techniques to the specific problem of determining the groove structure of diffraction gratings well enough to reliably predict performance. Metrology devices used include an atomic force microscope, a contact profilometer, and a late-model optical microinterferometer. Examples of shallow (far-UV, high dispersion) and deep (IR echelle) gratings are presented, along with some conclusions of which metrology techniques are applicable for which types of diffraction grating. Also required along with the metrology is the use of fast, full electromagnetic model efficiency calculation codes which calculate the efficiency to be expected from a given mount, materials set, and grating profile. We present results qualifying codes we use against known and published results. C1 NASA, Goddard Space Flight Ctr, Opt Branch, Greenbelt, MD 20771 USA. RP Content, D (reprint author), NASA, Goddard Space Flight Ctr, Opt Branch, MC551, Greenbelt, MD 20771 USA. NR 37 TC 9 Z9 9 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 405 EP 416 AR UNSP 4485-64 DI 10.1117/12.454276 PG 12 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500044 ER PT S AU Kuznetsov, IG Content, DA Boucarut, RA Madison, TJ AF Kuznetsov, IG Content, DA Boucarut, RA Madison, TJ BE Larar, AM Mlynczak, MG TI Design, performance and reliability of a high angular resolution, wide angular range, large aperture fully automated UV scatterometer. SO OPTICAL SPECTROSCOPIC TECHNIQUES, REMOTE SENSING, AND INSTRUMENTATION FOR ATMOSPHERIC AND SPACE RESEARCH IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Optical Spectroscopic Techniques, Remote Sensing, and Instrumentation for Atmospheric and Space Research CY JUL 30-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE, NASA Langley Res Ctr DE scatter; scatterometer; VUV; diffraction grating; grating efficiency; UV detectors; PMT ID REFLECTANCE DISTRIBUTION FUNCTION; BIDIRECTIONAL REFLECTANCE; DIFFRACTION GRATINGS; SCATTERED-LIGHT; INSTRUMENT; REFLECTOMETER; SURFACES; BRDF AB Design and performance of Fully Automated Ultraviolet Spectrographic Tester (FAUST) providing Bidirectional Scatter Distribution Function (BSDF) measurements at wavelengths ranging from the vacuum ultraviolet to the infrared has been described in details. The instrument is capable of measuring both very near (3 arcseconds) and very wide angle (over 120 degrees) scatter off both highly specular (mirrors and gratings) and highly diffuse surfaces for +/ 90 degrees incidence angle variations. Scatterometer dynamic range of over 11 orders of magnitude has been demonstrated. Stray light reduction techniques practicing for instrument signature improvement are discussed. Principles of light sources and detectors choice, instrument automation and calibration are explained. Instrument signature data along with some examples of a list of scatter measurements and gratings efficiency measurements performed by the use of FAUST are also presented here. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kuznetsov, IG (reprint author), NASA, Goddard Space Flight Ctr, MS 551, Greenbelt, MD 20771 USA. NR 29 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4199-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4485 BP 417 EP 428 AR UNSP 4485-65 PG 12 WC Engineering, Aerospace; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy SC Engineering; Instruments & Instrumentation; Remote Sensing; Optics; Spectroscopy GA BU15J UT WOS:000175162500045 ER PT S AU Papalexandris, MV Milman, MH Levine, M AF Papalexandris, MV Milman, MH Levine, M BE Hatheway, AE TI Optimization methods for thermal modeling of optomechanical systems SO OPTOMECHANICAL DESIGN AND ENGINEERING 2001 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Optomechanical Design and Engineering 2001 Conference CY AUG 02-03, 2001 CL SAN DIEGO, CA SP SPIE DE thermal networks; thermal control; estimation; optomechanical design; space telescopes AB Numerical techniques for a elms of optimization problems associated with the thermal modeling of optomechanical systems are presented. Emphasis is placed on applications where radiation plays a dominant role. This work is motivated by the need for incorporating thermal analysis into integrated modeling of high-precision, space-borne optical systems. The specific problems of interest are thermal control to minimize the wavefront error by application of external heat loads, and the temperature estimation problem of predicting temperatures at arbitrary nodes of the model given noisy measurements on a subset of nodes. The proposed numerical techniques axe briefly described and compared to existing algorithms. Their accuracy and robustness axe demonstrated through numerical tests with models from ongoing NASA missions. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Papalexandris, MV (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 7 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4158-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4444 BP 66 EP 77 DI 10.1117/12.447324 PG 2 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Optics SC Engineering; Optics GA BT65D UT WOS:000173644300008 ER PT S AU Craig, L Cline, T Hadaway, J Nein, M Smithers, M Keidel, J Stahl, P AF Craig, L Cline, T Hadaway, J Nein, M Smithers, M Keidel, J Stahl, P BE Hatheway, AE TI Structural analysis of a 50 cm diameter open-back triangular cell beryllium mirror in a cryogenic environment SO OPTOMECHANICAL DESIGN AND ENGINEERING 2001 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Optomechanical Design and Engineering 2001 Conference CY AUG 02-03, 2001 CL SAN DIEGO, CA SP SPIE AB This paper discusses NASTRAN finite element analysis of the Sub-scale Beryllium Mirror Demonstrator (SBMD), which has been developed by Ball Aerospace as an experimental lightweight (9.76 kg/m(2) areal density) design concept for the Next Generation Space Telescope (NGST). The mirror was repeatedly subjected to a 30 K environment in the large cryogenic test chamber at Marshall Space Flight Center (MSFC). Deformations on the mirror surface were measured optically. The surface distortions predicted by NASTRAN were analyzed for comparison with the measured values. Model results compared more favorably with measured results for the ambient temperature cases. For the cryogenic cases, the influence of geometry and material property variations was investigated to obtain closer correlation. C1 George C Marshall Space Flight Ctr, MSFC, AL 35812 USA. RP Craig, L (reprint author), George C Marshall Space Flight Ctr, ED22, MSFC, AL 35812 USA. NR 3 TC 1 Z9 1 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4158-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4444 BP 78 EP 89 DI 10.1117/12.447325 PG 2 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Optics SC Engineering; Optics GA BT65D UT WOS:000173644300009 ER PT S AU Stallcup, MA Lindner, JL AF Stallcup, MA Lindner, JL BE Hatheway, AE TI Analysis and verification of Hobby-Eberly Telescope 1 m mirror deflections due to edge sensor loading SO OPTOMECHANICAL DESIGN AND ENGINEERING 2001 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Optomechanical Design and Engineering 2001 Conference CY AUG 02-03, 2001 CL SAN DIEGO, CA SP SPIE DE finite element analysis; testing; mirror alignment; segmented mirror; edge sensors AB The ninety-one I m mirror segments which comprise the McDonald Observatory Hobby-Eberly Telescope (HET) primary mirror have been observed to drift out of alignment in an unpredictable manner in response to time variant temperature deviations. A Segment Alignment Maintenance System (SAMS) is being developed to detect and correct this segment-to-segment drift using sensors mounted at the edges of the mirror segments. However, the segments were not originally designed to carry the weight of edge sensors. Thus, analyses and tests were conducted as part of the SAMS design to estimate the magnitude and shape of the edge sensor induced deformations as well as the resultant optical performance. Interferometric testing of a 26 m radius of curvature HET mirror segment was performed at the NASA/Marshall Space Flight Center using several load conditions to verify the finite element analyses. RP Stallcup, MA (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4158-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4444 BP 102 EP 106 DI 10.1117/12.447292 PG 3 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Optics SC Engineering; Optics GA BT65D UT WOS:000173644300011 ER PT S AU Smith, WS Stahl, HP AF Smith, WS Stahl, HP BE Kahan, MA TI Overview of mirror technology development for large lightweight space-based optical systems SO OPTOMECHANICAL ENGINEERING 2000 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optomechanical Engineering 2000 CY NOV 07-08, 2000 CL BOSTON, MA SP SPIE AB The Space Optics Manufacturing Technology Center of Marshall Space Flight Center is involved in the development of lightweight optics for space-based systems. The NGST and other future NASA programs require large aperture space-based instruments. This paper reviews the technologies under development for NGST including discussions of the environmental testing of candidate segment for the NGST primary mirror. C1 NASA, George C Marshall Space Flight Ctr, Greenbelt, MD 20771 USA. RP Smith, WS (reprint author), NASA, George C Marshall Space Flight Ctr, Greenbelt, MD 20771 USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3863-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4198 BP 1 EP 8 DI 10.1117/12.417342 PG 8 WC Engineering, Mechanical; Optics SC Engineering; Optics GA BS17B UT WOS:000168950200001 ER PT S AU White, CV Levine, MB AF White, CV Levine, MB BE Kahan, MA TI Microdynamic issues in large deployable space telescopes SO OPTOMECHANICAL ENGINEERING 2000 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optomechanical Engineering 2000 CY NOV 07-08, 2000 CL BOSTON, MA SP SPIE DE precision; optical; deployable; microdynamics; analysis; hysteresis; joint slip; requirements flowdown AB This paper discusses a framework for microdynamic analysis -- analyzing a structure for nonlinear dynamic behavior in the nanometric regime -- and illustrates how microdynamic behaviors such as microlurch, joint snaps, and harmonic distortion fit within the framework. The framework is based on three types of nonlinear load-displacement behaviors associated with hysteresis in joints: deadzone, nonlinear elasticity, and hysteretic damping. The second part of the paper describes microdynamic analyses currently being used to flow optical performance requirements down to stability requirements at the component level. Such analyses are useful during error budget allocation exercises early in the mission design cycle. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP White, CV (reprint author), CALTECH, Jet Propuls Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3863-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4198 BP 163 EP 171 DI 10.1117/12.417338 PG 9 WC Engineering, Mechanical; Optics SC Engineering; Optics GA BS17B UT WOS:000168950200015 ER PT S AU Ritter, J Smith, WS AF Ritter, J Smith, WS BE Kahan, MA TI Electro-formed mirrors for both X-ray and visible astronomy SO OPTOMECHANICAL ENGINEERING 2000 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optomechanical Engineering 2000 CY NOV 07-08, 2000 CL BOSTON, MA SP SPIE DE replicated optics; electro-forming; large apertures; x-ray; infrared; gossamer; SXT; Constellation X ID CONSTELLATION-X; TELESCOPE; ELECTRODEPOSITION; NI; CO AB The Space Optics Manufacturing Technology Center of NASA's Marshall Space Flight Center is involved in the development of nickel and nickel alloy electroformed mirrors for rapid low cost production of space-based optical systems. The current state of the process is discussed for both Welter type x-ray mirrors and normal incidence mirrors for visible and infrared applications. C1 NASA, George C Marshall Space Flight Ctr, Natl Space Sci Technol Ctr, Huntsville, AL 35812 USA. RP Ritter, J (reprint author), NASA, George C Marshall Space Flight Ctr, Natl Space Sci Technol Ctr, Huntsville, AL 35812 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3863-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4198 BP 206 EP 212 DI 10.1117/12.417343 PG 7 WC Engineering, Mechanical; Optics SC Engineering; Optics GA BS17B UT WOS:000168950200018 ER PT J AU Steele, A Toporski, JKW Avci, R Guidry, S McKay, DS AF Steele, A Toporski, JKW Avci, R Guidry, S McKay, DS TI Time of flight secondary ion mass spectrometry (ToFSIMS) of a number of hopanoids SO ORGANIC GEOCHEMISTRY LA English DT Article ID TOF-SIMS; POLYMER SURFACES; CONTAMINATION AB Time of flight secondary ion mass spectrometry (ToFSIMS) has been applied to a number of bacterial hopanoids in an attempt to characterise these geologically important molecules in situ by a surface sensitive technique. Our results show that these molecules can be detected using this instrumentation to a high degree of mass accuracy. We believe that ToFSIMS can, therefore, be used to identify these molecules in environmental samples where sample size may be an issue and contraindicate the use of more traditional techniques such as GC-MS. (C) 2001 Published by Elsevier Science Ltd. C1 Univ Portsmouth, Sch Earth Environm & Phys Sci, Astrobiol Grp, Portsmouth PO1 3QL, Hants, England. NASA, Lyndon B Johnson Space Ctr, Astrobiol Grp, Houston, TX 77058 USA. Montana State Univ, Dept Phys, ICAL, Bozeman, MT 59717 USA. Univ Houston, Dept Geosci, Houston, TX 77204 USA. RP Steele, A (reprint author), Univ Portsmouth, Sch Earth Environm & Phys Sci, Astrobiol Grp, Burnaby Rd, Portsmouth PO1 3QL, Hants, England. NR 29 TC 24 Z9 24 U1 1 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0146-6380 J9 ORG GEOCHEM JI Org. Geochem. PY 2001 VL 32 IS 7 BP 905 EP 911 DI 10.1016/S0146-6380(01)00048-1 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 452XL UT WOS:000169884900003 ER PT B AU Young, DK Richardson, MD Briggs, KB AF Young, DK Richardson, MD Briggs, KB BE Aller, JY Woodin, SA Aller, RC TI Turbidites and benthic faunal succession in the deep sea: An ecological paradox? SO ORGANISM-SEDIMENT INTERACTIONS SE BELLE W BARUCH LIBRARY IN MARINE SCIENCE LA English DT Proceedings Paper CT Symposium on Organism-Sediment Interactions CY OCT, 1998 CL SC SP Natl Sci Fdn-Chem Oceanography Div, Dept Army, New England Regulat Div, Corps Engineers, Sci Applicat Int Corp, Natl Univ Ireland Galway, Yale Univ, Dept Geol & Geophys, SUNY, Marine Sci Res Ctr, Univ S Carolina, Belle Baruch Inst Marine Biol & Coast Res ID VENEZUELA BASIN; CARIBBEAN SEA; WASTE-DISPOSAL; ABYSSAL-PLAIN; COMMUNITY STRUCTURE; BIOLOGICAL-ACTIVITY; ATLANTIC-OCEAN; NORTH-ATLANTIC; SEDIMENTS; FLOOR AB Characteristics of benthic faunal succession following turbidity flows in the deep sea will vary according to the composition of turbidite materials, the spatial scales of deposition, the structure of initial benthic communities, and the frequency of depositional events. Despite a number of uncertainties regarding these effects, we make several generalizations in order to stimulate research on successional responses of benthic fauna to such episodic events. We find no support for a hypothesis formulated on the speculation by Heezen et al. (1955) that there should be, "... a high [positive] correlation between nutrient-rich turbidity current areas and a high standing crop of abyssal animals." There is no definitive evidence for the extensive 'mining' of deeply deposited sediments reported by Jumars and Gallagher (1982) as being a foraging strategy for deposit-feeding benthos in turbidite sediments. The time for complete recovery of the benthic fauna following an episodic deposition of material on the scale of a turbidity flow is postulated to be hundreds to thousands of tears. If viewed as a matrix of dynamic events, the effects of turbidity flows on abyssal fauna are on larger spatial and longer temporal scales than most other deep-sea disturbances and therefore provide the biological framework upon which many of the smaller and shorter term effects are superimposed. In interpreting and reconstructing causes for distributions of deep-sea organisms, benthic ecologists should incorporate a similarly holistic view (i.e., the turbidity current paradigm) as sedimentologists in order to better, understand how the abyssal benthic fauna has adapted to episodic disturbances over geologic time. C1 USN, Res Lab, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. RP Young, DK (reprint author), USN, Res Lab, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. NR 94 TC 4 Z9 4 U1 0 U2 2 PU UNIV SOUTH CAROLINA PRESS PI COLUMBIA PA COLUMBIA, SC 29208 USA BN 1-57003-431-1 J9 BEL BAR LIB PY 2001 IS 21 BP 101 EP 117 PG 17 WC Geochemistry & Geophysics; Ecology; Marine & Freshwater Biology SC Geochemistry & Geophysics; Environmental Sciences & Ecology; Marine & Freshwater Biology GA BU80U UT WOS:000177077400008 ER PT S AU Petre, R Hwang, U Allen, GE AF Petre, R Hwang, U Allen, GE BE Israel, MH TI Evidence for cosmic-ray acceleration in supernova remnants from X-ray observations SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID SHOCK ACCELERATION; CASSIOPEIA-A; EMISSION; SN-1006; ELECTRONS; DISCOVERY; SHELL; TEV AB Spatially-resolved X-ray spectroscopic observations over the past several years have led to the discovery of non-thermal X-ray emission arising in the shells of most young Galactic supernova remnants, most notably SN 1006 and Cas A. In addition, the X-ray emission from the shells of a few newly-discovered supernova remnants is dominated by a non-thermal component. This emission is thought to be synchrotron emission from electrons shock acclerated to hundreds of TeV, and thus represents strong evidence that cosmic rays are accelerated in SNR shocks. The inferences made using the X-ray observations are corroborated by the detection of TeV gamma -rays from two of these remnants. We review the status of the X-ray observations and describe how they can be used to provide insight into the shock-acceleration process. Published by Elsevier Science Ltd on behalf of COSPAR. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Greenbelt, MD 20771 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. RP Petre, R (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. NR 26 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 647 EP 652 DI 10.1016/S0273-1177(01)00105-3 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800001 ER PT S AU Boezio, M Barbiellini, G Bonvicini, V Schiavon, P Vacchi, A Zampa, N Bergstrom, D Carlson, P Francke, T Grinstein, S Weber, N Suffert, M Hof, M Kremer, J Menn, W Simon, M Stephens, SA Ambriola, M Bellotti, R Cafagna, FS Ciacio, F Circella, M De Marzo, C Finetti, N Papini, P Piccardi, S Spillantini, P Bartalucci, S Ricci, M Grimani, C Casolino, M De Pascale, MP Morselli, A Picozza, P Sparvoli, R Mitchell, JW Ormes, JF Streitmatter, RE Bravar, U Stochaj, SJ AF Boezio, M Barbiellini, G Bonvicini, V Schiavon, P Vacchi, A Zampa, N Bergstrom, D Carlson, P Francke, T Grinstein, S Weber, N Suffert, M Hof, M Kremer, J Menn, W Simon, M Stephens, SA Ambriola, M Bellotti, R Cafagna, FS Ciacio, F Circella, M De Marzo, C Finetti, N Papini, P Piccardi, S Spillantini, P Bartalucci, S Ricci, M Grimani, C Casolino, M De Pascale, MP Morselli, A Picozza, P Sparvoli, R Mitchell, JW Ormes, JF Streitmatter, RE Bravar, U Stochaj, SJ BE Israel, MH TI Measurements of cosmic-ray electrons and positrons by the WiZard/CAPRICE collaboration SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID RICH DETECTOR; SPECTRA; SPECTROMETER; CALORIMETER; PERFORMANCE; RADIATION AB Two recent balloon-borne experiments have been performed by the WiZard/CAPRICE collaboration in order to study the electron and positron components in the cosmic radiation. On 1994 August 8-9 the CAPRICE94 experiment flew from norther Canada and on 1998 May 28-29 the CAPRICE98 experiment flew from New Mexico, USA at altitudes corresponding to 3.9 and 5.5 g/cm(2) Of average residual atmosphere respectively. The apparatus were equipped with a, Ring Imaging Cherenkov (RICH) detector, a time-of-flight system, a superconducting magnet spectrometer with a tracking system and a 7-radiation-length silicon-tungsten imaging calorimeter. The RICH used in 1994 had a solid NaF radiator while in 1998 the RICH had a C4F10 gaseous radiator We report on the electron and positron spectra and positron fraction at the top of the atmosphere from few hundred MeV to 40 GeV measured by these two experiments. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Trieste, Dipartimento Fis, I-34147 Trieste, Italy. Ist Nazl Fis Nucl, Sez Trieste, I-34147 Trieste, Italy. Royal Inst Technol, S-10405 Stockholm, Sweden. Ctr Rech Nucl, F-67037 Strasbourg, France. Univ Gesamthsch Siegen, D-57068 Siegen, Germany. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Univ Bari, Dipartimento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, Sez Bari, I-70126 Bari, Italy. Univ Florence, Dipartimento Fis, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Sez Firenze, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Urbino, Ist Fis, I-61029 Urbino, Italy. Univ Rome, Dipartimento Fis, I-00133 Rome, Italy. Ist Nazl Fis Nucl, Sez Roma, I-00133 Rome, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. New Mexico State Univ, Las Cruces, NM 88003 USA. RP Boezio, M (reprint author), Univ Trieste, Dipartimento Fis, Via A Valerio 2, I-34147 Trieste, Italy. RI Cafagna, Francesco/A-9299-2010; Morselli, Aldo/G-6769-2011; Vacchi, Andrea/C-1291-2010; OI Boezio, Mirko/0000-0002-8015-2981; Cafagna, Francesco/0000-0002-7450-4784; Morselli, Aldo/0000-0002-7704-9553; Vacchi, Andrea/0000-0003-3855-5856; Bellotti, Roberto/0000-0003-3198-2708; casolino, marco/0000-0001-6067-5104; Sparvoli, Roberta/0000-0002-6314-6117; Picozza, Piergiorgio/0000-0002-7986-3321; Papini, Paolo/0000-0003-4718-2895 NR 25 TC 21 Z9 21 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 669 EP 674 DI 10.1016/S0273-1177(01)00108-9 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800004 ER PT S AU Maeno, T Nozaki, N Orito, S Matsunaga, H Abe, K Anraku, K Asaoka, Y Fujikawa, M Imori, M Makida, Y Matsui, N Matsumoto, H Mitchell, J Mitsui, T Moiseev, A Motoki, M Nishimura, J Ormes, J Saeki, T Sanuki, T Sasaki, M Seo, ES Shikaze, Y Sonoda, T Streitmatter, R Suzuki, J Tanaka, K Ueda, I Wang, JZ Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K AF Maeno, T Nozaki, N Orito, S Matsunaga, H Abe, K Anraku, K Asaoka, Y Fujikawa, M Imori, M Makida, Y Matsui, N Matsumoto, H Mitchell, J Mitsui, T Moiseev, A Motoki, M Nishimura, J Ormes, J Saeki, T Sanuki, T Sasaki, M Seo, ES Shikaze, Y Sonoda, T Streitmatter, R Suzuki, J Tanaka, K Ueda, I Wang, JZ Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K BE Israel, MH TI Precise measurements of cosmic-ray antiproton spectrum in a positive phase of the solar cycle SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID BLACK-HOLES; FLUX; MINIMUM AB The BESS spectrometer has measured the energy spectrum of cosmic-ray antiprotons successively in 1993, 1995, 1997 and 1998. In total, 848 antiprotons were clearly identified in energy range 0.18 to 4.20 GeV based on magnetic-rigidity, time-of-flight, energy loss, and Cherenkov radiation measurements. The measured antiproton spectra and antiproton/proton ratios were nearly identical at the upper end of the instrumental energy range, which is consistent with theoretical calculations. In the low energy region. our data show variations that are somewhat larger than expected. This might be due to statistical fluctuation, or might suggest a contribution of primary antiprotons from novel sources. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Kobe Univ, Kobe, Hyogo 6578501, Japan. Univ Tokyo, Tokyo 1130033, Japan. Univ Maryland, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. RP Maeno, T (reprint author), Kobe Univ, Kobe, Hyogo 6578501, Japan. RI MOTOKI, Masakazu/B-4212-2009; OI Seo, Eun-Suk/0000-0001-8682-805X NR 36 TC 1 Z9 1 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 711 EP 716 DI 10.1016/S0273-1177(01)00129-6 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800010 ER PT S AU Strong, AW Moskalenko, IV AF Strong, AW Moskalenko, IV BE Israel, MH TI Models for galactic cosmic-ray propagation SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID ISOTOPIC COMPOSITION; VOYAGER MEASUREMENTS; INTERSTELLAR-MEDIUM; MASS COMPOSITION; ENERGY-SPECTRA; NUCLEI; ELEMENTS; GALAXY; ANTIPROTONS; ABUNDANCES AB A new numerical model of particle propagation in the Galaxy has been developed, which allows the study of cosmic-ray and gamma-ray production and propagation in 2D or 3D, including a full reaction network. This is a further development of the code which has been used for studies of cosmic ray reacceleration, Galactic halo size, antiprotons and positrons in cosmic rays, the interpretation of diffuse continuum gamma rays, and dark matter. In this paper we illustrate recent results focussing on B/C, sub-Fe/Fe, ACE radioactive isotope data, source abundances and antiprotons. From the radioactive nuclei we derive a range of 3-7 kpc for the height of the cosmic-ray halo. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Strong, AW (reprint author), Max Planck Inst Extraterr Phys, Postfach 1312, D-85741 Garching, Germany. RI Moskalenko, Igor/A-1301-2007 OI Moskalenko, Igor/0000-0001-6141-458X NR 36 TC 70 Z9 71 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 717 EP 726 DI 10.1016/S0273-1177(01)00112-0 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800011 ER PT S AU Yanasak, NE Wiedenbeck, ME Binns, WR Christian, ER Cummings, AC Davis, AJ George, JS Hink, PL Israel, MH Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT AF Yanasak, NE Wiedenbeck, ME Binns, WR Christian, ER Cummings, AC Davis, AJ George, JS Hink, PL Israel, MH Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT BE Israel, MH TI Cosmic-ray time scales using radioactive clocks SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID ADVANCED-COMPOSITION-EXPLORER; ISOTOPIC COMPOSITION; INTERSTELLAR-MEDIUM; SHOCK ACCELERATION; LOW-ENERGY; PROPAGATION; ABUNDANCES; GALAXY; NUCLEOSYNTHESIS; NUCLEI AB Radionuclides in the galactic cosmic rays serve as chronometers for measuring the characteristic time of physical processes affecting cosmic ray energy spectra and composition. The radionuclide Ni-59, present in the ejecta of supernovae, will decay to Co-59 via electron-capture with a halflife of T-1/2 = 7.6 x 10(4) yr. However, if the cosmic ray acceleration time scale is shorter than the decay halflife, 59Ni will become fully-stripped of electrons and will be present in the cosmic rays. Abundances of cosmic ray Ni-59 and Co-59 measured with the Cosmic Ray Isotope Spectrometer (CRIS) are consistent with the decay of all source Ni-59, implying an acceleration time delay > 10(5) yr. Abundances of the beta -decay radioactive secondaries, produced by fragmentation of the cosmic rays during transport in the interstellar medium (ISM), depend on the time scales for spallation and escape from the Galaxy. Consequently, measurement of these abundances can be used to derive the galactic confinement time, tau (esc) for cosmic rays. Using the abundances of the beta -decay species Be-10, Al-26, Cl-36, and Mn-54 measured by CRIS, we find a confinement time tau (esc) similar to 15 Myr. Published by Elsevier Science Ltd on behalf of COSPAR. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Washington Univ, St Louis, MO 63130 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Pasadena, CA 91125 USA. RP Yanasak, NE (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 51 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 727 EP 736 DI 10.1016/S0273-1177(01)00114-4 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800012 ER PT S AU Jones, FC Lukasiak, A Ptuskin, VS Webber, WR AF Jones, FC Lukasiak, A Ptuskin, VS Webber, WR BE Israel, MH TI K-capture cosmic ray secondaries and reacceleration SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID LIQUID-HYDROGEN TARGET; PRODUCTION CROSS-SECTIONS; RELATIVISTIC NUCLEI; PROPAGATION; NE-22; BEAMS; FRAGMENTS; ISOTOPES; GALAXY; CARBON AB We have investigated the effect of reacceleration on interstellar flux of K-capture secondaries V-49 and Cr-51. Several isotopic ratios for these two isotopes are calculated using the galactic diffusion model with and without distributed reacceleration. It is found that the statistical accuracy of the ACE experiment on itself is high enough to see a signature of reacceleration. However, the uncertainties in nuclear production cross sections are probably too large to conclude that reacceleration process took place. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. Russian Acad Sci, IZMIRAN, Troitsk 142092, Moscow Region, Russia. New Mexico State Univ, Las Cruces, NM 88003 USA. RP Jones, FC (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. NR 14 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 737 EP 741 DI 10.1016/S0273-1177(01)00113-2 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800013 ER PT S AU Streitmatter, RE Stephens, SA AF Streitmatter, RE Stephens, SA BE Israel, MH TI The abundance of radioactive nuclei under different physical environments around the solar system SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID PROPAGATION; BE-10 AB Differential equations describing the propagation of cosmic-ray nuclei from Be-7 to Fe-56 in a homogeneous interstellar medium (ISM) were solved simultaneously in the time domain, so as to determine the escape path length using the observed B/C ratio as a constraint. The spectra of nuclei thus obtained were then used to obtain the Be-10/Be-9 ratio as a function of energy. From a comparison with the data, we determined the mean density of n(H) in the confinement volume of cosmic rays to be 0.2 atom/cc and the corresponding escape life time of 30 My. The effect of the solar system being in a "local bubble" of low density was examined. It was found that if cosmic-ray nuclei have spent considerable amount of time in the local bubble, the mean value Of nH in the Galaxy needs to be raised to account for the observation. The ratio of Al-26/Al-17 and Cl-36/Cl are more sensitive to the propagation in the local hole and cur study showed that in order that the data are consistent with each other, the diffusion co-efficient in the local bubble should be > 10(29)cm(2)/s. This clearly demonstrates the need to include in the diffusion models the variation of diffusion co-efficient with gas density. We then examined the effect of the local hole on the abundance ratio of C-14/C-13 and bring out the need to measure C-14 to further constrain the diffusion co-efficient in the local hole. Published by Elsevier Science Ltd on behalf of COSPAR. C1 NASA, Goddard Space Flight Ctr, High Energy Phys Lab, Greenbelt, MD 20771 USA. Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. RP Streitmatter, RE (reprint author), NASA, Goddard Space Flight Ctr, High Energy Phys Lab, Code 661, Greenbelt, MD 20771 USA. NR 13 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 743 EP 748 DI 10.1016/S0273-1177(01)00115-6 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800014 ER PT S AU Stephens, SA Streitmatter, RE AF Stephens, SA Streitmatter, RE BE Israel, MH TI Source composition of cosmic ray nuclei SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID ENERGY-SPECTRA AB During propagation in the Galaxy, cosmic-ray nuclei undergo spallation and as a result, their composition at the time of acceleration gets modified. Propagation models have been used to obtain the source composition from the observed abundance. We made use of the standard leaky-box model with time as the propagation variable to examine the spectra of all elements. The main ingredients in this method are the spallation cross-sections, which has considerably changed over the time. Using the latest available cross-sections, we show that the spectral index of the power-law injection spectrum in rigidity is -2.32. We also derive the escape path-length and the source abundances. The derived abundances differ from those of Webber for some of the elements. Published by Elsevier Science Ltd on behalf of COSPAR. C1 Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. NASA, Goddard Space Flight Ctr, High Energy Phys Lab, Greenbelt, MD 20771 USA. RP Stephens, SA (reprint author), Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan. NR 21 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 749 EP 754 DI 10.1016/S0273-1177(01)00123-5 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800015 ER PT S AU Circella, M Ambriola, M Barbiellini, G Bartalucci, S Bellotti, R Bergstrom, D Bidoli, V Boezio, M Bonvicini, V Bravar, U Cafagna, F Carlson, P Casolino, M Ciacio, F Circella, M De Marzo, C De Pascale, MP Finetti, N Francke, T Grimani, C Grinstein, S Hof, M Kremer, J Menn, W Mitchell, JW Morselli, A Ormes, JF Papini, P Piccardi, S Picozza, P Ricci, M Schiavon, P Simon, M Sparvoli, R Spillantini, P Stephens, SA Stochaj, SJ Streitmatter, RE Suffert, M Vacchi, A Weber, N Zampa, N AF Circella, M Ambriola, M Barbiellini, G Bartalucci, S Bellotti, R Bergstrom, D Bidoli, V Boezio, M Bonvicini, V Bravar, U Cafagna, F Carlson, P Casolino, M Ciacio, F Circella, M De Marzo, C De Pascale, MP Finetti, N Francke, T Grimani, C Grinstein, S Hof, M Kremer, J Menn, W Mitchell, JW Morselli, A Ormes, JF Papini, P Piccardi, S Picozza, P Ricci, M Schiavon, P Simon, M Sparvoli, R Spillantini, P Stephens, SA Stochaj, SJ Streitmatter, RE Suffert, M Vacchi, A Weber, N Zampa, N CA WiZard Collaboration BE Israel, MH TI Measurements of primary cosmic-ray hydrogen and helium by the wizard collaboration SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID ATMOSPHERIC MUONS; SPECTRA; FLUX; PROTONS AB We present the measurements of primary protons and helium nuclei performed by the WiZard Collaboration in different balloon-borne campaigns. A superconducting magnet spectrometer was used in these experiments together with detectors for particle recognition. These combinations of detectors made it possible to perform accurate particle measurements over a large (up to 200 GV for protons) energy interval. We focus in particular on the results from the MASS91 and CAPRICE94 experiments: We find a very good agreement between these two sets of measurements, also in comparison to other recent results. All these results seem to suggest that the normalization of primary cosmic rays may be significantly lower than previously estimated. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Bari, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Univ Trieste, I-34147 Trieste, Italy. Ist Nazl Fis Nucl, I-34147 Trieste, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Royal Inst Technol, S-10405 Stockholm, Sweden. New Mexico State Univ, RL Golden Particle Astrophys Lab, Las Cruces, NM 88003 USA. Univ Roma Tor Vergata, I-00133 Rome, Italy. Ist Nazl Fis Nucl, I-00133 Rome, Italy. Univ Florence, I-50125 Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Univ Gesamthsch Siegen, D-57068 Siegen, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Ctr Rech Nucl, F-67037 Strasbourg, France. RP Circella, M (reprint author), Univ Bari, Via Amendola 173, I-70126 Bari, Italy. RI Morselli, Aldo/G-6769-2011; Cafagna, Francesco/A-9299-2010; Vacchi, Andrea/C-1291-2010; OI Morselli, Aldo/0000-0002-7704-9553; Cafagna, Francesco/0000-0002-7450-4784; Vacchi, Andrea/0000-0003-3855-5856; Bellotti, Roberto/0000-0003-3198-2708; casolino, marco/0000-0001-6067-5104; Sparvoli, Roberta/0000-0002-6314-6117; Picozza, Piergiorgio/0000-0002-7986-3321; Papini, Paolo/0000-0003-4718-2895; Boezio, Mirko/0000-0002-8015-2981 NR 16 TC 1 Z9 1 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 755 EP 760 DI 10.1016/S0273-1177(01)00117-X PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800016 ER PT S AU Sanuki, T Matsumoto, H Nozaki, M Abe, K Anraku, K Asaoka, Y Fujikawa, M Imori, M Maeno, T Makida, Y Matsui, N Matsunaga, H Mitchell, J Mitsui, T Moiseev, A Motoki, M Nishimura, J Orito, S Ormes, J Saeki, T Sasaki, M Seo, ES Shikaze, Y Sonoda, T Streitmatter, R Suzuki, J Tanaka, K Ueda, I Wang, JZ Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K AF Sanuki, T Matsumoto, H Nozaki, M Abe, K Anraku, K Asaoka, Y Fujikawa, M Imori, M Maeno, T Makida, Y Matsui, N Matsunaga, H Mitchell, J Mitsui, T Moiseev, A Motoki, M Nishimura, J Orito, S Ormes, J Saeki, T Sasaki, M Seo, ES Shikaze, Y Sonoda, T Streitmatter, R Suzuki, J Tanaka, K Ueda, I Wang, JZ Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K BE Israel, MH TI Precise measurements of cosmic-ray hydrogen and helium spectra with BESS SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID PROTON; FLUX; ATMOSPHERE; NUCLEI AB A series of Balloon-borne Experiments with a Superconducting Spectrometer, BESS, has been made since 1993. We report here the absolute cosmic-ray proton and helium spectra in energy ranges of 1 to 120 GeV and I to 54 GeV/nucleon, respectively, as measured by the 1998 balloon flight of the BESS spectrometer. Those spectra were determined within overall uncertainties of +/-5 % for protons and +/- 10 % for helium nuclei including statistical and systematic errors. The covered energy range is relevant to the atmospheric neutrinos observed as "fully contained events" in Super-Kamiokande. In order to extend the energy range up to around I TeV, we have started to design and develop new tracking detectors. Those energy spectra in a higher energy region will help to estimate the interstellar spectra of primary cosmic rays and the absolute fluxes of "up-going muons." (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Tokyo, Bunkyo Ku, Tokyo 1130033, Japan. Kobe Univ, Kobe, Hyogo 6578501, Japan. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 3050801, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, College Pk, MD 20742 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. RP Sanuki, T (reprint author), Univ Tokyo, Bunkyo Ku, Tokyo 1130033, Japan. RI MOTOKI, Masakazu/B-4212-2009; OI Seo, Eun-Suk/0000-0001-8682-805X NR 18 TC 4 Z9 4 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 761 EP 766 DI 10.1016/S0273-1177(01)00118-1 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800017 ER PT S AU Binns, WR Wiedenbeck, ME Christian, ER Cummings, AC George, JS Hink, PL Israel, MH Klarmann, J Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE AF Binns, WR Wiedenbeck, ME Christian, ER Cummings, AC George, JS Hink, PL Israel, MH Klarmann, J Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE BE Israel, MH TI Galactic cosmic ray neon isotopic abundances measured by the cosmic ray isotope spectrometer (CRIS) on ACE SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID ADVANCED-COMPOSITION-EXPLORER; SOLAR; STARS; METEORITES; EVOLUTION; ANOMALIES; ELEMENTS; GALAXY AB We present measurements of neon isotopic abundances from the ACE-CRIS experiment. These abundances have been obtained in seven energy intervals over the energy range of similar to 80 less than or equal toE less than or equal to 280 MeV/nucleon. We find that the Ne-22/Ne-20 abundance ratio at the cosmic-ray source is a factor of 5.0 +/-0.2 greater than for the solar wind. These measured abundances agree well with previous experiments. The significance of these results is discussed. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Washington Univ, St Louis, MO 63130 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Pasadena, CA 91125 USA. RP Binns, WR (reprint author), Washington Univ, St Louis, MO 63130 USA. RI Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 31 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 767 EP 772 DI 10.1016/S0273-1177(01)00119-3 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800018 ER PT S AU Wiedenbeck, ME Binns, WR Christian, ER Cummings, AC Davis, AJ George, JS Hink, PL Israel, MH Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE AF Wiedenbeck, ME Binns, WR Christian, ER Cummings, AC Davis, AJ George, JS Hink, PL Israel, MH Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE BE Israel, MH TI The isotopic source composition of cosmic-ray iron, cobalt, and nickel SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID VOYAGER MEASUREMENTS; ABUNDANCES; NUCLEI; NUCLEOSYNTHESIS; SILICON; FE; ACCELERATION; RADIATION; EVOLUTION; ELEMENTS AB The isotopic composition of cosmic-ray Fe, Co, and Ni at energies similar to 150-500 MeV/nucleon has been measured with the Cosmic-Ray Isotope Spectrometer (CRIS) instrument on ACE. Source abundances have been derived from a leaky-box propagation model using secondary species in the range 41 less than or equal to A less than or equal to 55 to constrain the calculated secondary contributions to the Fe, Co, and Ni isotopes. The derived relative source abundances bear a strong resemblance to solar-system values. The most significant difference, an excess of similar to (70 +/- 30)%, is found for the source abundance ratio (58)Fe/(56)Fe. Some implications of the derived source composition for the origin of cosmic rays are discussed. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Washington Univ, St Louis, MO 63130 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Pasadena, CA 91125 USA. RP Wiedenbeck, ME (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 28 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES-SERIES PY 2001 VL 27 IS 4 BP 773 EP 778 DI 10.1016/S0273-1177(01)00120-X PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800019 ER PT S AU George, JS Wiedenbeck, ME Barghouty, AF Binns, WR Christian, ER Cummings, AC Hink, PL Leske, RA Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE AF George, JS Wiedenbeck, ME Barghouty, AF Binns, WR Christian, ER Cummings, AC Hink, PL Leske, RA Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE BE Israel, MH TI Distinguishing galactic cosmic-ray source models with first ionization potential and volatility SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID ENERGETIC PARTICLES; SOLAR; ABUNDANCES; NUCLEOSYNTHESIS; ACCELERATION; CONSTRAINTS; ELEMENTS; NUCLEI AB Studies of the galactic cosmic-ray source composition reveal a pattern in the elemental abundances that may be controlled by the first ionization potential (FIP) or a closely correlated parameter, the condensation temperature (volatility). Determining the true parameter is key identifying the galactic cosmic-ray source (GCRS) material. Using data from the CRIS instrument onboard the ACE spacecraft, we examine five elements that are more volatile than other elements of similar FIR Three of these (Na, Cu, Ge) show small deficits in their source abundances that may suggest a volatility-dependent fractionation. The source abundances of Ga and Zn (an intermediate FIP element) are consistent with either model. Possible systematic uncertainties from the cosmic-ray pathlength estimate as well as effects due to the instrumental acceptance are discussed. We also compare the GCRS composition to that observed in solar energetic particles. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 CALTECH, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Roanoke Coll, Dept Phys, Salem, VA 24153 USA. Washington Univ, St Louis, MO 63130 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP George, JS (reprint author), CALTECH, Pasadena, CA 91125 USA. RI Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 21 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 779 EP 784 DI 10.1016/S0273-1177(01)00116-8 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800020 ER PT S AU Adams, J Bashindzhagyan, G Bashindzhagyan, P Chilingarian, A Drury, L Egorov, N Golubkov, S Korotkova, N Menn, W Panasyuk, M Podorozhnyi, D Procureur, J Roganova, T Saavedra, O Sidorov, A Simon, M Sveshnikova, L Thompson, A Turundaevsky, A Yashin, I AF Adams, J Bashindzhagyan, G Bashindzhagyan, P Chilingarian, A Drury, L Egorov, N Golubkov, S Korotkova, N Menn, W Panasyuk, M Podorozhnyi, D Procureur, J Roganova, T Saavedra, O Sidorov, A Simon, M Sveshnikova, L Thompson, A Turundaevsky, A Yashin, I BE Israel, MH TI An instrument to measure elemental energy spectra of cosmic-ray nuclei up to 10(16) eV SO ORIGIN AND ACCELERATION OF COSMIC RAYS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 3 Symposium of COSPAR-Scientific-Commission-E held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP COSPAR ID SILICON STRIP DETECTORS AB A longstanding goal of cosmic-ray research is to measure the elemental energy spectra of cosmic rays up to and through the "knee" (approximate to 3x10(15) eV). It is not currently feasible to achieve this goal with an ionisation calorimeter because the mass required to be deployed in Earth orbit is very large (at least 50 tonnes). An alternative method is presented. This is based on measuring the primary particle energy by determining the angular distribution of secondaries produced in a target layer using silicon microstrip detector technology. The proposed technique can be used over a wide range of energies (10(11)-10(16) eV) and gives an energy resolution of 60% or better. Based on this technique, a design for a new lightweight instrument with a large aperture (KLEM) is described. Published by Elsevier Science Ltd on behalf of COSPAR. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia. Yerevan Phys Inst, Yerevan 375036, Armenia. Dublin Inst Adv Studies, Dublin 4, Ireland. Res Inst Mat Sci & Technol, Zelenograd, Russia. Univ Siegen, D-5900 Siegen, Germany. Ctr Nucl Energy, Gradignan, France. Univ Turin, Turin, Italy. RP Adams, J (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RI chilingarian, ashot/B-1901-2014; Panasyuk, Mikhail/E-2005-2012; Drury, Luke/B-1916-2017; Roganova, Tatiana/E-2118-2012 OI chilingarian, ashot/0000-0002-2018-9715; Drury, Luke/0000-0002-9257-2270; Roganova, Tatiana/0000-0002-6645-7543 NR 5 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 4 BP 829 EP 833 DI 10.1016/S0273-1177(01)00127-2 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS72Y UT WOS:000171020800028 ER PT B AU Barnes, A AF Barnes, A BE Scherer, K Fichtner, H Fahr, HJ Marsch, E TI Interaction of the local interstellar medium with the heliosphere: role of the interior and exterior magnetic fields SO OUTER HELIOSPHERE: THE NEXT FRONTIERS, PROCEEDINGS SE COSPAR COLLOQUIA SERIES LA English DT Proceedings Paper CT 11th COSPAR Colloquium on Outer Heliosphere - The Next Frontiers CY JUL 24-28, 2000 CL POTSDAM, GERMANY SP Max-Planck Inst Aeronomie ID SOLAR-WIND INTERACTION; TERMINATION SHOCK MOTION; RADIAL IMF COMPONENT; INTERPLANETARY DISTURBANCES; LATITUDINAL DEPENDENCE; FLOW DOWNSTREAM; MHD SIMULATION; MODEL; HELIOPAUSE; INTERFACE AB This paper reviews the role that the exterior magnetic field (of interstellar origin) and the interior magnetic field (of solar origin) may play in the heliosphere-LISM interaction. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Barnes, A (reprint author), NASA, Ames Res Ctr, Div Space Sci, 245-3, Moffett Field, CA 94035 USA. EM abarnes@mail.arc.nasa.gov NR 61 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND BN 0-444-50909-7 J9 COSPAR COLL PY 2001 VL 11 BP 43 EP 52 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BV09S UT WOS:000177816500005 ER PT B AU Moskalenko, IV Christian, ER Moiseev, AA Ormes, JF Strong, AW AF Moskalenko, IV Christian, ER Moiseev, AA Ormes, JF Strong, AW BE Scherer, K Fichtner, H Fahr, HJ Marsch, E TI Antiprotons below 200 MeV in the interstellar medium: perspectives for observing exotic matter signatures SO OUTER HELIOSPHERE: THE NEXT FRONTIERS, PROCEEDINGS SE COSPAR COLLOQUIA SERIES LA English DT Proceedings Paper CT 11th COSPAR Colloquium on Outer Heliosphere - The Next Frontiers CY JUL 24-28, 2000 CL POTSDAM, GERMANY SP Max-Planck Inst Aeronomie ID COSMIC-RAY NUCLEONS; DARK-MATTER; GAMMA-RAYS; SPECTRUM; HELIUM; PROTON; GALAXY AB Most cosmic ray antiprotons observed near the Earth are secondaries produced in collisions of energetic cosmic ray (CR) particles with interstellar gas. The spectrum of secondary antiprotons is expected to peak at similar to 2 GeV and decrease sharply at lower energies. This leaves a low energy window in which to look for signatures of exotic processes such as evaporation of primordial black holes or dark matter annihilation. In the inner heliosphere, however, modulation of CRs by the solar wind makes analysis difficult. Detecting these antiprotons outside the heliosphere on an interstellar probe removes most of the complications of modulation. We present a new calculation of the expected secondary antiproton flux (the background) as well as a preliminary design of a light-weight, low-power instrument for the interstellar probe to make such measurements. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Moskalenko, IV (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Christian, Eric/D-4974-2012; Moskalenko, Igor/A-1301-2007 OI Christian, Eric/0000-0003-2134-3937; Moskalenko, Igor/0000-0001-6141-458X NR 14 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND BN 0-444-50909-7 J9 COSPAR COLL PY 2001 VL 11 BP 195 EP 198 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BV09S UT WOS:000177816500026 ER PT B AU Sackheim, R Van Dyke, M Houts, M Poston, D Lipinski, R Polk, J Frisbee, R AF Sackheim, R Van Dyke, M Houts, M Poston, D Lipinski, R Polk, J Frisbee, R BE Scherer, K Fichtner, H Fahr, HJ Marsch, E TI In-space nuclear power as an enabling technology for exploration of the outer heliopause SO OUTER HELIOSPHERE: THE NEXT FRONTIERS, PROCEEDINGS SE COSPAR COLLOQUIA SERIES LA English DT Proceedings Paper CT 11th COSPAR Colloquium on Outer Heliosphere - The Next Frontiers CY JUL 24-28, 2000 CL POTSDAM, GERMANY SP Max-Planck Inst Aeronomie AB Deep space missions, both for scientific and human exploration and development, are as weight limited today as they were 35 yr ago. Right behind the weight constraints is the nearly equally important mission limitation of cost. Launch vehicles, upper stages, and in-space propulsion systems also cost about the same today with the same efficiency as they have had for many years (excluding impact of inflation). These dual mission constraints combine to force either very expensive, megasystem missions or very light weight, but high risk/low margin planetary spacecraft designs, such as the recent unsuccessful attempts for an extremely low cost mission to Mars during the 1998-99 opportunity (Mars Climate Orbiter and Mars Polar Lander). When one considers spacecraft missions to the heliopause, the enormous weight and cost constraints will impose even more daunting concerns for mission cost, risk, and the ability to establish adequate mission margins for success. This paper will address the benefits of using a safe in-space nuclear reactor as the basis for providing both sufficient electric energy and high performance space propulsion that will greatly reduce mission risk and significantly increase weight initial mass in low-Earth orbit (IMLEO) and cost margins. Weight and cost margins are increased by enabling much higher payload fractions and redundant design features for a given launch vehicle (higher payload fraction of IMLEO). This paper will also discuss and summarize the recent advances in nuclear reactor technology and safety of modem reactor designs and operating practices and experience, as well as advances in reactor control coupled with high power generation and high performance nuclear thermal and electric propulsion technologies. It will be shown that these nuclear propulsion and power technologies are major enabling capabilities for higher reliability, higher margin and lower cost deep space missions designed to reliably reach the heliopause for scientific exploration. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Sackheim, R (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND BN 0-444-50909-7 J9 COSPAR COLL PY 2001 VL 11 BP 399 EP 409 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BV09S UT WOS:000177816500055 ER PT B AU Liewer, PC Mewaldt, RA Ayon, JA Garner, C Gavit, S Wallace, RA AF Liewer, PC Mewaldt, RA Ayon, JA Garner, C Gavit, S Wallace, RA BE Scherer, K Fichtner, H Fahr, HJ Marsch, E TI Interstellar probe using a solar sail: Conceptual design and technological challenges SO OUTER HELIOSPHERE: THE NEXT FRONTIERS, PROCEEDINGS SE COSPAR COLLOQUIA SERIES LA English DT Proceedings Paper CT 11th COSPAR Colloquium on Outer Heliosphere - The Next Frontiers CY JUL 24-28, 2000 CL POTSDAM, GERMANY SP Max-Planck Inst Aeronomie AB NASA's Interstellar Probe, conceived to travel to 200-400 AU, will be the first spacecraft designed specifically to explore the unknown regions beyond the solar system and directly sample the dust, neutrals and plasma of the surrounding interstellar material. Here we present the mission concept developed by NASA's Interstellar Probe Science and Technology Definition Team in 1999 and discuss the technological challenges it presents. The Team selected a solar sail concept in which the spacecraft reaches 200 AU in 15 years. This rapid passage is made by using a 400-m diameter solar sail and heading first inward to similar to0.25 AU to increase the radiation pressure. The Probe then heads out in the interstellar upwind direction at similar to14/AU year, about 5 times the speed of the Voyager 1 and 2 spacecraft. Advanced lightweight instruments and spacecraft systems, as well as solar sail propulsion, are needed to achieve these high speeds. The spacecraft coasts to 200-400 AU, exploring the Kuiper Belt, the boundaries of the heliosphere, and the nearby interstellar medium. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Liewer, PC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 6 Z9 6 U1 2 U2 2 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND BN 0-444-50909-7 J9 COSPAR COLL PY 2001 VL 11 BP 411 EP 420 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BV09S UT WOS:000177816500056 ER PT B AU Gazis, PR AF Gazis, PR BE Scherer, K Fichtner, H Fahr, HJ Marsch, E TI Artificial intelligence techniques for the onboard analysis of space science data SO OUTER HELIOSPHERE: THE NEXT FRONTIERS, PROCEEDINGS SE COSPAR COLLOQUIA SERIES LA English DT Proceedings Paper CT 11th COSPAR Colloquium on Outer Heliosphere - The Next Frontiers CY JUL 24-28, 2000 CL POTSDAM, GERMANY SP Max-Planck Inst Aeronomie AB Future space science missions will face severe constraints on communications bandwidth. This is particularly true for missions such as the proposed Interstellar Probe, for which the data volume from even a minimal science package could overwhelm any conceivable communications link. The traditional response to low communications bandwidth has been to reduce time resolution. This is unlikely to be satisfactory when the data rate is extremely low. One solution to this problem might be to use artificial intelligence (AI) techniques to identify interesting data on board the spacecraft for return to Earth at higher resolution. We are evaluating several AI techniques for onboard science analysis of space science data. These techniques included several different neural network architectures as well as conventional rule-based systems. We will discuss several aspects of these techniques: 1) their utility and capabilities for space science data analysis, 2) their ability to identify interesting events and novel time periods, 3) reliability, sensitivity, and false positive rates, 4) operational requirements, such as communications bandwidth and any need for external oversight. C1 NASA, Ames Res Ctr, SJSU Fdn, Moffett Field, CA 94035 USA. RP Gazis, PR (reprint author), NASA, Ames Res Ctr, SJSU Fdn, Moffett Field, CA 94035 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND BN 0-444-50909-7 J9 COSPAR COLL PY 2001 VL 11 BP 435 EP 438 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BV09S UT WOS:000177816500059 ER PT B AU Corcoran, MF Ishibashi, K Swank, JH Petre, R AF Corcoran, MF Ishibashi, K Swank, JH Petre, R BE DeGroot, M Sterken, C TI X-ray emission and variability of eta Carinae SO P CYGNI 2000 : 400 YEARS OF PROGRESS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT P Cygni 2000 Workshop CY AUG 21-23, 2000 CL ARMAGH, NORTH IRELAND SP Armagh Observ, First Trust Bank AB We review the X-ray properties of the supermassive LBV 97 Carinae, and briefly compare the X-ray observations of eta Carinae with P Cygni, another "canonical" LBV. In the rest of this paper we try to fit the RXTE light curve with a colliding-wind emission model to refine the ground-based orbital elements. Our X-ray light curve modelling suggests that the mass-loss rate from eta Carinae is generally less than 3 x 10(-4) M-circle * yr(-1), about a factor of 5 lower than that derived from some observations in other wavebands. We could not match the duration of the X-ray minimum with any colliding-wind model in which the wind is spherically symmetric and the mass-loss rate is constant. However, we show that we can match the variations around X-ray minimum if we include an increase of a factor of similar to 20 in the mass-loss rate from eta Carinae for approximately 80 days following periastron. Based on the X-ray fluxes, the distance to eta Carinae is 2300 pc with formal uncertainties of only similar to 10%. C1 NASA, Goddard Space Flight Ctr, USRA, LHEA, Greenbelt, MD 20771 USA. RP Corcoran, MF (reprint author), NASA, Goddard Space Flight Ctr, USRA, LHEA, Code 662, Greenbelt, MD 20771 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-070-6 J9 ASTR SOC P PY 2001 VL 233 BP 75 EP 80 PG 6 WC Astronomy & Astrophysics; Spectroscopy SC Astronomy & Astrophysics; Spectroscopy GA BU31P UT WOS:000175668800008 ER PT B AU Gang, T AF Gang, T BE DeGroot, M Sterken, C TI Ultra-high resolution spectroscopy of P Cygni and similar stars in the optical wavelength region SO P CYGNI 2000 : 400 YEARS OF PROGRESS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT P Cygni 2000 Workshop CY AUG 21-23, 2000 CL ARMAGH, NORTH IRELAND SP Armagh Observ, First Trust Bank ID SPECTRAL ATLAS; VARIABILITY AB present and discuss optical spectra of Luminous Blue Variables (LBVs) with resolutions of R approximate to 50 000-100 000 and high signal-to-noise ratios (S/N approximate to 100-1000, depending on wavelength region and object). None of the stars show significant variations in their spectra during our snap-shot observations (time-scale of a few hours). All objects exhibit inhomogeneities in their line profiles that get more pronounced and more frequent in spectral lines that are formed further out in the atmosphere. These findings indicate that LBVs might have non-uniform wind structures where clumps and/or shells could be common features. All spectra and their detailed descriptions can be found in chapter 4 and the appendix of the Ph.D. thesis at: http://chippewa.nascom.nasa.gov/gaeng/. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gang, T (reprint author), NASA, Goddard Space Flight Ctr, Code 682-4, Greenbelt, MD 20771 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-070-6 J9 ASTR SOC P PY 2001 VL 233 BP 129 EP 132 PG 4 WC Astronomy & Astrophysics; Spectroscopy SC Astronomy & Astrophysics; Spectroscopy GA BU31P UT WOS:000175668800016 ER PT B AU Gull, T Ishibashi, K Davidson, K AF Gull, T Ishibashi, K Davidson, K BE DeGroot, M Sterken, C TI Nebular observations of the ejecta surrounding eta Carinae using the STIS and HST SO P CYGNI 2000 : 400 YEARS OF PROGRESS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT P Cygni 2000 Workshop CY AUG 21-23, 2000 CL ARMAGH, NORTH IRELAND SP Armagh Observ, First Trust Bank AB We are using the Space Telescope Imaging Spectrograph (STIS) with the Hubble Space Telescope (HST) to study Eta Carinae and its associated ejecta. The 52" x 0.1" aperture and medium-dispersion gratings with CCD provide angular resolution of 0.1" and spectral resolving power of 5000 from 1640 to 10100Angstrom. Observations began at the spectroscopic minimum in early 1998 with the intent to study the time-development of the star and nebulosity through one 5.5-year spectroscopic period. As the star increased in brightness, the nebula underwent very significant changes in brightness, ionization, line emission and structure. A major program is underway to identify the many new lines measured in this series of observations, to model the nebular conditions and to describe the spatial structure of the ejecta. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gull, T (reprint author), NASA, Goddard Space Flight Ctr, Code 681, Greenbelt, MD 20771 USA. RI Gull, Theodore/D-2753-2012 OI Gull, Theodore/0000-0002-6851-5380 NR 2 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-070-6 J9 ASTR SOC P PY 2001 VL 233 BP 185 EP 188 PG 4 WC Astronomy & Astrophysics; Spectroscopy SC Astronomy & Astrophysics; Spectroscopy GA BU31P UT WOS:000175668800022 ER PT B AU Galbraith, L AF Galbraith, L GP SMTA SMTA TI High density microelectronics packaging roadmap for space applications SO PAN PACIFIC MICROELECTRONICS SYMPOSIUM, 2001, PROCEEDINGS LA English DT Proceedings Paper CT 6th Annual Pan Pacific Microelectronics Symposium CY FEB 13-16, 2001 CL ISL KAUAI, HI SP Surface Mount Technol Assoc, GPD Global, IMAPS, ITRI, Japan Inst Electr Packaging, Semiconduct Equipment & Mat Int, SMT China, Surface Mount Circuit Board Assoc DE microelectronic packaging; roadmap; trends; forecasts AB High density interconnect microelectronics emphasizes the effective integration of several critical and complex electronic packages and technologies. This Roadmap introduces current technologies in use, related strategic issues and trends, and research recommendations for space applications. Electronic packages arc optimized for low cost, portability, robustness, high speed, power efficiency, and for small size and loin, weight. Satisfying these increasing demands will require enhanced electronic performance with an associated improvement in packaging performance and better relief from thermal and mechanical stresses. Technical challenges and directions for high density interconnect microelectronics packaging include understanding latent electromigration and dendritic growth, multilayer board hole wall wicking reliability issues, and characterization of reworkable inexpensive underfill, Current research directions include Vertical Cavity Surface Emitting Laser (VCSEL) packaging for low cost optical interconnects, high density vias, and stencil printing with conductive adhesives for direct chip attach. Technology challenges arc described first for components. Forecasts and recommendations for research direction are given for components, materials, and packaging. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 15 TC 1 Z9 2 U1 1 U2 3 PU SURFACE MOUNT TECHNOLOGY ASSOC PI EDINA PA 5200 WILLSON RD, SUITE 215, EDINA, MN 55424-1343 USA PY 2001 BP 91 EP 96 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BU69T UT WOS:000176732600011 ER PT B AU Barr, SL AF Barr, SL GP SMTA SMTA TI Dimpled ball grid array process development for space flight applications SO PAN PACIFIC MICROELECTRONICS SYMPOSIUM, 2001, PROCEEDINGS LA English DT Proceedings Paper CT 6th Annual Pan Pacific Microelectronics Symposium CY FEB 13-16, 2001 CL ISL KAUAI, HI SP Surface Mount Technol Assoc, GPD Global, IMAPS, ITRI, Japan Inst Electr Packaging, Semiconduct Equipment & Mat Int, SMT China, Surface Mount Circuit Board Assoc DE BGA; D-BGA; process; validation AB With smaller and smaller Printed Wiring Board (PWB) form factors, such as CompactPCI((R)) the need for smaller packages with high I/Os has grown significantly. Thus, the use of Ball Grid Array, packages has become necessary for space flight applications. A Jet Propulsion Laboratory/NASA technology and system development program that services various spacecraft missions uses a 3U CompactPCI((R)) form factor. The System Input/Output board requires a large amount of I/Os and has limited area, so conventional packages, such as quad flat packs will not fit. Thus, the use of Ball Grid Arrays (BGAs) with much smaller package dimensions than leaded packages are needed to meet area requirements and are being evaluated for spaceflight applications. Since this type of package has not been used in past space flight environments, it was necessary to develop a process that would yield robust and reliable solder joints. The process, developing assembly, inspection and rework techniques, were verified by conducting environmental tests. The test article was a printed wiring assembly, (PWA) consisting of four daisy chained D-BGA packages. Visual inspection of the outer solder joints and real time X-ray were used to verify solder quality. Three environmental tests were conducted: random vibration at 0.2 g(2)/Hz, pyro shock at 2000g for 50 ms, and thermal cycling from -55degreesC to 100degreesC for 200 cycles. The test article was electrically monitored for shorts and opens at or above 1 mus during all environmental tests, After testing, Scanning Electron Microscope (SEM) analysis was performed on various D-BGA cross sections to determine the quality of the package-to-board interface. The 472 D-BGA solder attachments passed the above environmental tests meeting the minimum requirements for use on space flight electronics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Barr, SL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SURFACE MOUNT TECHNOLOGY ASSOC PI EDINA PA 5200 WILLSON RD, SUITE 215, EDINA, MN 55424-1343 USA PY 2001 BP 339 EP 350 PG 12 WC Engineering, Electrical & Electronic SC Engineering GA BU69T UT WOS:000176732600043 ER PT B AU Ricks, KG Weir, JM Wells, BE AF Ricks, KG Weir, JM Wells, BE BE Sha, E TI SADL: Simulation architecture description language SO PARALLEL AND DISTRIBUTED COMPUTING SYSTEMS LA English DT Proceedings Paper CT 14th International Conference on Parallel and Distributed Computing Systems CY AUG 08-10, 2001 CL RICHARDSON, TX SP Int Soc Comp & Their Applicat DE Architecture Description Language; real-time; hardware in-the-loop simulation; software architecture; simulation model AB This paper introduces the Simulation Architecture Description Language (SADL) developed at the National Aeronautics and Space Administration's Marshall Space Flight Center to support the real-time simulation of advanced avionics systems. SADL is a graphical, domain-specific Architecture Description Language that facilitates the high-level specification of both the software and hardware aspects of hard real-time, hardware-in-the-loop, avionics system simulations targeted for execution on diverse hardware architectures including multiprocessor systems. It supports the hierarchical expression of the architecture of an entire simulation at various levels of abstraction. A detailed description of SADL is provided. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Ricks, KG (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU INTERNATIONAL SOCIETY COMPUTER S & THEIR APPLICATIONS (ISCA) PI RALEIGH PA 8820 SIX FORKS ROAD, RALEIGH, NC 27615 USA BN 1-880843-39-0 PY 2001 BP 219 EP 224 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Theory & Methods SC Computer Science GA BV53S UT WOS:000179289500036 ER PT J AU Balsara, DS Norton, CD AF Balsara, DS Norton, CD TI Highly parallel structured adaptive mesh refinement using parallel language-based approaches SO PARALLEL COMPUTING LA English DT Article; Proceedings Paper CT Conference on High Performance Computing Users and Intel Supercomputer Users Group CY 1999 CL SUNY, STONY BROOK, NY HO SUNY DE parallel adaptive mesh refinement; fortran 90; distributed shared memory; load balancer; finite difference methods ID RADIATION MAGNETOHYDRODYNAMICS CODE; 2 SPACE DIMENSIONS; HYPERBOLIC CONSERVATION-LAWS; BOUNDARY-VALUE-PROBLEMS; LINEARIZED FORMULATION; ASTROPHYSICAL FLOWS; RIEMANN PROBLEM; ISOTHERMAL MAGNETOHYDRODYNAMICS; HYDRODYNAMIC ALGORITHMS; EULER EQUATIONS AB Adaptive Mesh Refinement (AMR) calculations carried out on structured meshes play an exceedingly important role in several areas of science and engineering. This is so not just because AMR techniques allow us to carry out calculations very efficiently but also because they model very precisely the multi-scale fashion in which nature itself works. Many AMR applications are also amongst the most computationally intensive calculations undertaken making it necessary to use parallel supercomputers for their solution. While class library-based approaches are being attempted for parallel AMR we point out here that recent advances in the Fortran 90/95 standard and the OpenMP standard now make it possible to carry out highly parallel AMR calculations using language-based approaches, The language-based approaches offer several advantages over library-based approaches, the two principal ones being portability across parallel platforms and the best possible utilization of Distributed Shared Memory (DSM) hardware on machines that have such hardware. They also free up the applications scientist from being constrained by the static features of a class library. The choice of Fortran also ensures maximal reuse of pre-existing Fortran 77 applications and full Fortran 77-based processing efficiency on each computational node. Our implementation of the ideas presented here in the first author's RIEMANN framework essentially permits any serial, uniform grid, stencil-based Fortran code to be turned into a parallel AMR code, In this paper we first describe our strategy for using Fortran 90 in an object-oriented fashion, This permits AMR applications to be expressed in terms of familiar abstractions that are natural to the process of solving AMR hierarchies. We then describe the OpenMP features that are useful for parallel processing of AMR hierarchies in a load balanced fashion on multiprocessors. The automatic. parallel regridding of AMR hierarchies is also described. We then present a very efficient load balancer and show how it is to be used for load balanced solution of AMR hierarchies. Our load balancer is extremely general and should also see use in other disciplines. We follow this up with the application of the parallel AMR techniques developed here to the solution of elliptic and hyperbolic problems. For our elliptic problem we choose parallel, self-adaptive multigrid as an example. For our hyperbolic problem we choose time-dependent MHD as an example. In either case illustrative information is given about the adaptive processing of these systems. We also provide detailed scalability studies for both the above-mentioned problems which show that our methods scale extremely well up to several hundreds of processors. (C) 2001 Elsevier Science B.V. All rights reserved. C1 NASA, Jet Prop Lab, CALTECH, Pasadena, CA 91109 USA. Univ Illinois, NCSA, Champaign, IL 61820 USA. Univ Illinois, CSAR, Champaign, IL 61820 USA. RP NASA, Jet Prop Lab, CALTECH, MS 168-522,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM dbalsara@ncsa.uiuc.edu; nortonc@bryce.jpl.nasa.gov NR 60 TC 16 Z9 16 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 EI 1872-7336 J9 PARALLEL COMPUT JI Parallel Comput. PD JAN PY 2001 VL 27 IS 1-2 BP 37 EP 70 DI 10.1016/S0167-8191(00)00088-0 PG 34 WC Computer Science, Theory & Methods SC Computer Science GA 417AX UT WOS:000167814100003 ER PT B AU Smith, W Gunter, D Quesnel, D AF Smith, W Gunter, D Quesnel, D BE Arabnia, HR TI An XML-Based protocol for distributed event services SO PDPTA'2001: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 2001) CY JUN 25-28, 2001 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Int Technol Inst, Korea Informat Processing Soc, World Acad Sci Informat Technol, PACT Corp DE event service; XML; distributed computing; computational grids AB A recent trend in distributed computing is the construction of high-performance distributed systems called computational grids. One difficulty we have encountered is that there is no standard format for the representation of performance information and no standard protocol for transmitting this information. This limits the types of performance analysis that can be undertaken in complex distributed systems. To address this problem, we present an XML-based protocol for transmitting performance events in distributed systems and evaluate the performance of this protocol. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Smith, W (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-71-8 PY 2001 BP 1668 EP 1674 PG 3 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BT77Y UT WOS:000174014500252 ER PT S AU Trujillo, AC AF Trujillo, AC GP IEE IEE TI Response times in correcting non-normal system events when collocating status, alerts and procedures, and controls SO PEOPLE IN CONTROL SE IEE CONFERENCE PUBLICATIONS LA English DT Proceedings Paper CT 2nd International Conference on Human Interfaces in Control Rooms, Cockpits and Command Centres CY JUN 19-21, 2001 CL UNIV MANCHESTER, INST SCI TECHNOL, MANCHESTER, ENGLAND SP Inst Elect Engineers, Human Syst Engn Grp, British Comp Soc, Inst Chem Engineers, Dept Trade & Ind, Inst Highways & Transportat, Ergonom Soc, Inst Mech Engineers HO UNIV MANCHESTER, INST SCI TECHNOL AB Currently, most of the displays in control rooms can be categorized as status, alerts/procedures, or control screens. With the advent and use of CRTs and the associated computing power available to compute and display information, it is now possible to combine these different elements of information and control onto a single display. An experiment was conducted to determine which, if any, of these functions should be collocated in order to better handle simple anticipated non-normal system events. The results indicated that there are performance benefits and subject preferences to combining all the information onto one screen or combining the status and alert/procedure information onto one screen and placing the controls in another area. C1 NASA, Langley Res Ctr, Washington, DC 20546 USA. RP Trujillo, AC (reprint author), NASA, Langley Res Ctr, Washington, DC 20546 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU INST ELECTRICAL ENGINEERS INSPEC INC PI EDISON PA 379 THORNALL ST, EDISON, NJ 08837 USA SN 0537-9989 BN 0-85296-742-X J9 IEE CONF PUBL PY 2001 IS 481 BP 8 EP 13 PG 6 WC Automation & Control Systems; Computer Science, Information Systems; Ergonomics SC Automation & Control Systems; Computer Science; Engineering GA BT83K UT WOS:000174172100003 ER PT J AU Chukova, SV Kaiander, IN Ahumada, AJ AF Chukova, S. V. Kaiander, I. N. Ahumada, A. J., Jr. TI Is apparent motion real or really apparent? SO PERCEPTION LA English DT Meeting Abstract C1 [Chukova, S. V.] Russian Acad Sci, Pavlov Inst Physiol, St Petersburg 199034, Russia. [Kaiander, I. N.] AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. [Ahumada, A. J., Jr.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM Sveta@chvs.infran.ru NR 0 TC 0 Z9 0 U1 0 U2 0 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON NW2 5JN, ENGLAND SN 0301-0066 J9 PERCEPTION JI Perception PY 2001 VL 30 BP 79 EP 79 PG 1 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA V05FY UT WOS:000207113100250 ER PT J AU Brooks, K AF Brooks, K TI Stereomotion speed perception is contrast dependent SO PERCEPTION LA English DT Article ID MOTION-IN-DEPTH; PERCEIVED SPEED; SPATIAL-FREQUENCY; CYCLOPEAN MOTION; DISCRIMINATION; DIRECTION; MECHANISMS; THRESHOLDS AB The effect of contrast on the perception of stimulus speed for stereomotion and monocular lateral motion was investigated for successive matches in random-dot stimuli. The familiar 'Thompson effect'-that a reduction in contrast leads to a reduction in perceived speed-was found in similar proportions for both binocular images moving in depth, and for monocular images translating laterally. This result is consistent with the idea that the monocular motion system has a significant input to the stereomotion system, and dominates the speed percept for approaching motion. C1 Univ Sussex, Dept Expt Psychol, Brighton BN1 9QG, E Sussex, England. RP Brooks, K (reprint author), NASA, Ames Res Ctr, Human Informat Proc Res Branch, M-S 262-2, Moffett Field, CA 94035 USA. OI Brooks, Kevin/0000-0003-1424-4092 NR 27 TC 33 Z9 33 U1 0 U2 1 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON NW2 5JN, ENGLAND SN 0301-0066 J9 PERCEPTION JI Perception PY 2001 VL 30 IS 6 BP 725 EP 731 DI 10.1068/p3143 PG 7 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA 450FW UT WOS:000169731700007 PM 11464560 ER PT J AU Eckstein, MP Beutter, BR Stone, LS AF Eckstein, MP Beutter, BR Stone, LS TI Quantifying the performance limits of human saccadic targeting during visual search SO PERCEPTION LA English DT Article ID FRONTAL EYE FIELD; SIGNAL-DETECTION; STRUCTURED BACKGROUNDS; NEURAL BASIS; CONTRAST; NOISE; IDENTIFICATION; MOVEMENTS; LOCATION; DISCRIMINATION AB In previous studies of saccadic targeting, the issue how visually guided saccades to unambiguous targets are programmed and executed has been examined. These studies have found different degrees of guidance for saccades depending on the task and task difficulty. In this study, we use ideal-observer analysis to estimate the visual information used for the first saccade during a search for a target disk in noise. We quantitatively compare the performance of the first saccadic decision to that of the ideal observer (ie absolute efficiency of the first saccade) and to that of the associated final perceptual decision at the end of the search (ie relative efficiency of the first saccade). Our results show, first, that at all levels of salience tested, the first saccade is based on visual information from the stimulus display, and its highest absolute efficiency is similar to 20%. Second, the efficiency of the first saccade is lower than that of the final perceptual decision after active search with eye movements) and has a minimum relative efficiency of 19% at the lowest level of saliency investigated. Third, we found that requiring observers to maintain central fixation (no saccades allowed) decreased the absolute efficiency of their perceptual decision by up to a factor of two, but that the magnitude of this effect depended on target salience. Our results demonstrate that ideal-observer analysis can be extended to measure the visual information mediating saccadic target-selection decisions during visual search, which enables direct comparison of saccadic and perceptual efficiencies. C1 NASA, Ames Res Ctr, Human Factors Res & Technol Div, Human Informat Proc Res Branch, Moffett Field, CA 94035 USA. Univ Calif Santa Barbara, Dept Psychol, Santa Barbara, CA 93106 USA. RP Eckstein, MP (reprint author), NASA, Ames Res Ctr, Human Factors Res & Technol Div, Human Informat Proc Res Branch, Moffett Field, CA 94035 USA. NR 42 TC 37 Z9 37 U1 0 U2 0 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON NW2 5JN, ENGLAND SN 0301-0066 J9 PERCEPTION JI Perception PY 2001 VL 30 IS 11 BP 1389 EP 1401 DI 10.1068/p3128 PG 13 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA 500UU UT WOS:000172645800009 PM 11768491 ER PT J AU Cohen, MM Stoper, AE Welch, RB DeRoshia, CW AF Cohen, MM Stoper, AE Welch, RB DeRoshia, CW TI Effects of gravitational and optical stimulation on the perception of target elevation SO PERCEPTION & PSYCHOPHYSICS LA English DT Article ID PERCEIVED EYE LEVEL; VISUAL-FIELD PITCH AB To examine the combined effects of gravitational and optical stimulation on perceived target elevation, we independently altered gravitational-inertial force and both the orientation and the structure of a background visual array. While being exposed to 1.0, 1.5, or 2.0 G(Z), in the human centrifuge at NASA Ames Research Center, observers attempted to set a target to the apparent horizon. The target was viewed against the far wall of a box that was pitched at various angles. The box was brightly illuminated, had only its interior edges dimly illuminated, or was kept dark. Observers lowered their target settings as G(Z) was increased; this effect was weakened when the box was illuminated. Also, when the box was visible, settings were displaced in the same direction as that in which the box was pitched. We attribute our results to the combined influence of otolith-oculomotor mechanisms that underlie the elevator illusion and visual-oculomotor mechanisms (optostatic responses) that underlie the perceptual effects of viewing pitched visual arrays. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Calif State Univ Hayward, Hayward, CA 94542 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Cohen, MM (reprint author), NASA, Ames Res Ctr, Mail Stop 262-2, Moffett Field, CA 94035 USA. NR 23 TC 11 Z9 11 U1 1 U2 1 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 USA SN 0031-5117 J9 PERCEPT PSYCHOPHYS JI Percept. Psychophys. PD JAN PY 2001 VL 63 IS 1 BP 29 EP 35 DI 10.3758/BF03200500 PG 7 WC Psychology; Psychology, Experimental SC Psychology GA 409GD UT WOS:000167375400003 PM 11304014 ER PT S AU Gunapala, S Bandara, S Bock, J Ressler, M Liu, J Mumolo, J Rafol, S Ting, D Werner, M AF Gunapala, S Bandara, S Bock, J Ressler, M Liu, J Mumolo, J Rafol, S Ting, D Werner, M BE Brown, GJ Razeghi, M TI Large format long-wavelength GaAs/AlGaAs multi-quantum well infrared detector arrays for astronomy SO PHOTODETECTORS: MATERIALS AND DEVICES VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Photodetectors - Materials and Devices VI CY JAN 22-24, 2001 CL SAN JOSE, CA SP SPIE ID PHOTODETECTORS; CAMERA; GAIN AB A long-wavelength large format Quantum Well Infrared Photodetector (QWIP) focal plane array has been successfully used in a ground based astronomy experiment. QWIP arrays afford greater flexibility than the usual extrinsically doped semiconductor infrared (IR) arrays. The wavelength of the peak response and cutoff can be continuously tailored over a range wide enough to enable light detection at any wavelength range between 6-20 mum. The spectral band width of these detectors can be tuned from narrow (Delta lambda/lambda similar to 10 %) to wide (Delta lambda/lambda similar to 40%) allowing various applications. Also, QWIP device parameters can be optimized to achieve extremely high performances at lower operating temperatures (similar to 30 K) due to exponential suppression of dark current. Furthermore, QWIPs offer low cost per pixel and highly uniform large format focal plane arrays (FPAs) mainly due to mature GaAs/A1GaAs growth and processing technologies. The other advantages of GaAs/A1GaAs based QWIPs are higher yield, lower 1/f noise and radiation hardness. Recently, we operated an infrared camera with a 256x256 QWIP array sensitive at 8.5 mum at the prime focus of the 5-m Hale telescope, obtaining the images. The remarkable noise stability - and low 1/f noise - of QWIP focal plane arrays enable camera to operate by modulating the optical signal with a nod period up to 100 s. A 500 s observation on dark sky renders a flat image with little indication of the low spatial frequency structures associated with imperfect sky subtraction or detector drifts. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gunapala, S (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 11 TC 3 Z9 3 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3966-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4288 BP 278 EP 285 DI 10.1117/12.429415 PG 4 WC Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics; Physics, Applied SC Instruments & Instrumentation; Materials Science; Optics; Physics GA BS89K UT WOS:000171334100032 ER PT S AU Stirbl, R Pain, B Cunningham, T Hancock, B Yang, G Heynssens, J Wrigley, C AF Stirbl, R Pain, B Cunningham, T Hancock, B Yang, G Heynssens, J Wrigley, C BE Berghmans, F Taylor, EW TI Advances in ultra-low power, highly integrated, Active Pixel Sensor CMOS imagers for space and radiation environments SO PHOTONICS FOR SPACE AND RADIATION ENVIRONMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 2nd Conference on Photonics for Space and Radiation Environments CY SEP 17-18, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, CNES, NASA DE active pixel sensor; optical communications; radiation tolerant; start trackers; CMOS imager; visible detector ID STAR AB To develop more cost-effective future satellites and spacecraft systems, instruments and avionics are evolving into smaller/lighter-weight and more power efficient modules. NASA's future missions will require that these lighter weight systems have smaller shielding mass margins and operate at cryogenics temperatures in stressing radiation. JPL has been exploring several approaches to improving the radiation performance of CMOS Active Pixel Sensor (APS) imagers for ultra-low power, "smart" science cameras, star trackers, and optical link beacon trackers to be used in next generation space systems. Active Pixel Sensor CMOS imagers, fabricated on a 0.5 micron RHCMOS process line, are being designed and tested to investigate the incorporation of on-chip digital control and timing, adaptive windowing with digital or analog output for ultra-low power, data-channel efficient on-chip preprocessing, with no blooming and wide dynamic range. These imagers also provide excellent performance at cryogenic operating temperatures appropriate to some anticipated flight missions. Ultra-low power APS imagers with their high level of integration, on-chip timing and control and environmental robustness are excellent candidates for NASA's earth observing, interplanetary and deep space exploration missions. This presentation will give the status of the work in the development of these radiation-robust, ultra-low power photodiode APS devices. C1 CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. RP Stirbl, R (reprint author), CALTECH, Jet Prop Lab, NASA, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4272-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4547 BP 1 EP 10 PG 10 WC Optics SC Optics GA BU44A UT WOS:000175999000001 ER PT S AU Flanegan, M AF Flanegan, M BE Berghmans, F Taylor, EW TI Fiber optic system on NASA GLAS Spaceflight instrument SO PHOTONICS FOR SPACE AND RADIATION ENVIRONMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 2nd Conference on Photonics for Space and Radiation Environments CY SEP 17-18, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, CNES, NASA DE Spaceflight fiber optics; GLAS; IceSat AB GLAS is a satellite laser altimeter designed to measure ice-sheet topography and cloud and atmospheric properties. The onboard Nd:YAG laser emits 1064nm and (frequency doubled) 532nm light, which is reflected from the Earth and atmosphere and collected by a telescope. A small portion of the light emitted toward the Earth is picked off by a free space to fiber optic coupling system and routed around the instrument by connectorized fiber optic cables. There is also a 2 kin fiber optic delay line to provide for onboard timing calibration, a fiber optic pigtailed diode laser onboard test source and a fiber optic connectorized LED onboard test source. The stability of the signals through the fiber optic system must be maintained to 10% in amplitude and 20ps in timing for certain critical signal paths. It has been challenging to meet these requirements with the spacecraft resources available. Components from many commercial vendors have been used to satisfy these requirements. The system design, components selected and testing performed will be discussed in this paper. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Flanegan, M (reprint author), NASA, Goddard Space Flight Ctr, Code 554, Greenbelt, MD 20771 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4272-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4547 BP 86 EP 93 PG 8 WC Optics SC Optics GA BU44A UT WOS:000175999000011 ER PT J AU Kamiya, K Nemirovskii, S Murakami, M AF Kamiya, K Nemirovskii, S Murakami, M TI Dynamical characteristics of the propagation of He-I-He-II interface created by fast reduction of vapor pressure SO PHYSICA B LA English DT Article DE He-I-He-II interface; superconducting temperature sensor; NK theory AB A He-I-He-II interface is generated by rapidly reducing the temperature of He-I so as to pass the lambda -point under saturated vapor pressure. The dynamical characteristics of the interface are examined by measuring its propagation speed. A theory is proposed and compared with the experimental data. (C) 2001 Elsevier Science B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Tsukuba, Inst Mech Engn & Syst, Tsukuba, Ibaraki 3058573, Japan. Russian Acad Sci, Inst Thermophys, Novosibirsk 630090, Russia. RP Kamiya, K (reprint author), NASA, Goddard Space Flight Ctr, Code 552, Greenbelt, MD 20771 USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 2001 VL 293 IS 3-4 BP 347 EP 349 DI 10.1016/S0921-4526(00)00528-7 PG 3 WC Physics, Condensed Matter SC Physics GA 401LV UT WOS:000166929800019 ER PT J AU Nikjoo, H Uehara, S Khvostunov, IG Cucinotta, FA Wilson, WE Goodhead, DT AF Nikjoo, H Uehara, S Khvostunov, IG Cucinotta, FA Wilson, WE Goodhead, DT TI Monte Carlo track structure for radiation biology and space applications SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE Monte Carlo; cross-sections; microdosimetry; TEPC ID RAY-SCATTERING SPECTROSCOPY; LIQUID WATER; CROSS-SECTIONS; ELASTIC-SCATTERING; OPTICAL-SPECTRA; ELECTRON-SPECTRA; SIMULATION; VAPOR; RADIOBIOLOGY; IMPACT AB Over the past two decades event by event Monte Carlo track structure codes have increasingly been used for biophysical modelling and radiotherapy. Advent of these codes has helped to shed light on many aspects of microdosimetry and mechanism of damage by ionising radiation in the cell, These codes have continuously been modified to include new improved cross sections and computational techniques. This paper provides a summary of input data for ionizations, excitations and elastic scattering cross sections for event by event Monte Carlo track structure simulations for electrons and ions in the form of parametric equations, which makes it easy to reproduce the data. Stopping power and radial distribution of dose are presented for ions and compared with experimental data. A model is described for simulation of full slowing down of proton tracks in water in the range 1 keV to 1 MeV. Modelling and calculations are presented for the response of a TEPC proportional counter irradiated with 5 MeV alpha-particles. Distributions are presented for the wall and wall-less counters. Data shows contribution of indirect effects to the lineal energy distribution for the wall counters responses even at such a low ion energy. C1 MRC, Radiat & Genome Stabil Unit, Harwell OX11 0RD, Berks, England. Kyushu Univ, Sch Hlth Sci, Fukuoka, Japan. MRRC, Med Radiol Res Ctr, Obninsk, Russia. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Washington State Univ, Richland, WA 99352 USA. NR 52 TC 20 Z9 22 U1 0 U2 3 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 38 EP 44 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900010 PM 11770535 ER PT J AU Wilson, JW Cucinotta, FA Kim, MHY Schimmerling, W AF Wilson, JW Cucinotta, FA Kim, MHY Schimmerling, W TI Optimized shielding for space radiation protection SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE human exploration; Galactic Cosmic Radiation; shielding materials AB Future deep space mission and International Space Station exposures ME be dominated by the high-charge and -energy (HZE) ions of the Galactic Cosmic Rays (GCR). A few mammalian systems have been extensively tested over a broad range of ion types and energies. For example, C31410T1/2 cells, V79 cells, and Harderian aland tumors have been described by various track-structure dependent response models. The attenuation of GCR induced biological effects depends strongly on the biological endpoint, response model used, and material composition. Optimization of space shielding is then driven by the nature of the response model and the transmission characteristics of the given material. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Coll William & Mary, Williamsburg, VA 23187 USA. NASA, Washington, DC 20546 USA. NR 14 TC 26 Z9 26 U1 0 U2 1 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 67 EP 71 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900014 PM 11770540 ER PT J AU Kim, MHY Thibeault, SA Wilson, JW Heilbronn, L Kiefer, RL Weakley, JA Dueber, JL Fogarty, T Wilkins, R AF Kim, MHY Thibeault, SA Wilson, JW Heilbronn, L Kiefer, RL Weakley, JA Dueber, JL Fogarty, T Wilkins, R TI Radiation protection using Martian surface materials in human exploration of Mars SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE human exploration; galactic cosmic radiation; Martian regolith; polyimides AB To develop materials for shielding astronauts from the hazards of GCR, natural Martian surface materials are considered for their potential as radiation shielding for manned Mars missions. The modified radiation fluences behind various kinds of Martian rocks and regolith are determined by solving the Boltzmann equation using NASA Langley's HZETRN code along with the 1977 Solar Minimum galactic cosmic ray environmental model. To develop structural shielding composite materials for Martian surface habitats, theoretical predictions of the shielding properties of Martian regolith/polyimide composites has been computed to assess their shielding effectiveness. Adding high-performance polymer binders to Martian regolith to enhance structural properties also enhances the shielding properties of these composites because of the added hydrogenous constituents. Heavy ion beam testing of regolith simulant/polyimide composites is planned to validate this prediction. Characterization and proton beam tests are performed to measure structural properties and to compare the shielding effects on microelectronic devices, respectively. C1 Coll William & Mary, Williamsburg, VA 23187 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Prairie View A&M Univ, Prairie View, TX 77446 USA. RI Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 5 TC 1 Z9 1 U1 1 U2 5 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 81 EP 83 PG 3 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900016 PM 11770542 ER PT J AU Pinsky, LS Wilson, TL Ferrari, A Sala, P Carminati, F Brun, R AF Pinsky, LS Wilson, TL Ferrari, A Sala, P Carminati, F Brun, R TI Development of a space radiation Monte Carlo computer simulation based on the FLUKA and ROOT codes SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE cosmic rays; Monte Carlo; transport code; simulation software AB This NASA funded project is proceeding to develop a Monte Carlo-based computer simulation of the radiation environment in space. With actual funding only initially in place at the end of May 2000, the study is still in the early stage of development. The general tasks have been identified and personnel have been selected. The code to be assembled will be based upon two major existing software packages. The radiation transport simulation will be accomplished by updating the FLUKA Monte Carlo program, and the user interface will employ the ROOT software being developed at CERN. The end-product will be a Monte Carlo-based code which will complement the existing analytic codes such as BRYNTRN/ HZETRN presently used by NASA to evaluate the effects of radiation shielding in space. The planned code will possess the ability to evaluate the radiation environment for spacecraft and habitats in Earth orbit, in interplanetary space, on the lunar surface, or on a planetary surface such as Mars. Furthermore, it will be useful in the design and analysis of experiments such as ACCESS (Advanced Cosmic-ray Composition Experiment for Space Station), which is an Office of Space Science payload currently under evaluation for deployment on the International Space Station (ISS). FLUKA will be significantly improved and tailored for use in simulating space radiation in four ways. First, the additional physics not presently within the code that is necessary to simulate the problems of interest, namely the heavy ion inelastic processes, will be incorporated. Second, the internal geometry package will be replaced with one that will substantially increase the calculation speed as well as simplify the data input task. Third, default incident flux packages that include all of the different space radiation sources of interest will be included. Finally, the user interface and internal data structure will be melded together with ROOT, the object-oriented data analysis infrastructure system. Beyond the benefits of 'objectivity', ROOT's incorporation will also provide a graphical user interface with powerful tools for input prior to the calculation, as well as for data analysis and visualization of the results. C1 Univ Houston, Houston, TX 77004 USA. NASA, Johnson Space Flight Ctr, Houston, TX USA. Ist Nazl Fis Nucl, I-20133 Milan, Italy. CERN, CH-1211 Geneva, Switzerland. RI sala, paola/E-2868-2013 OI sala, paola/0000-0001-9859-5564 NR 14 TC 3 Z9 3 U1 0 U2 1 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 86 EP 89 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900018 PM 11770544 ER PT J AU Singleterry, RC Wilson, JW Shinn, JL Tripathi, RK Thibeault, SA Noor, AK Cucinotta, FA Badavi, FF Chang, CK Qualls, GD Clowdsley, MS Kim, MHY Heinbockel, JH Norbury, J Blattning, SR Miller, J Zeitlin, C Heilbronn, LH AF Singleterry, RC Wilson, JW Shinn, JL Tripathi, RK Thibeault, SA Noor, AK Cucinotta, FA Badavi, FF Chang, CK Qualls, GD Clowdsley, MS Kim, MHY Heinbockel, JH Norbury, J Blattning, SR Miller, J Zeitlin, C Heilbronn, LH TI Creation and utilization of a World Wide Web based space radiation effects code: SIREST SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE space radiation; collaborative design; design optimization; space radiation transport AB In order for humans and electronics to fully and safely operate in the space environment, codes like HZETRN (High Charge and Energy Transport) must be included in any designer's toolbox for design evaluation with respect to radiation damage. Currently, spacecraft designers do not have easy access to accurate radiation codes like HZETRN to evaluate their design for radiation effects on humans and electronics. Today, the World Wide Web is sophisticated enough to support the entire HZETRN code and all of the associated pre and post processing tools. This package is called SIREST (Space Ionizing Radiation Effects and Shielding Tools). There are many advantages to SIREST. The most important advantage is the instant update capability of the web. Another major advantage is the modularity that the web imposes on the code. Right now, the major disadvantage of SIREST will be its modularity inside the designer's system. This mostly comes from the fact that a consistent interface between the designer and the computer system to evaluate the design is incomplete. This, however, is to be solved in the Intelligent Synthesis Environment (ISE) program currently being funded by NASA. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Univ Virginia, NASA, Langley Res Ctr, Hampton, VA USA. Johnson Space Flight Ctr, Houston, TX USA. Christopher Newport Univ, Newport News, VA 23606 USA. FDC NYMA Inc, Hampton, VA USA. CNR, Washington, DC 20418 USA. Coll William & Mary, Williamsburg, VA USA. Old Dominion Univ, Norfolk, VA USA. Univ Wisconsin, Milwaukee, WI 53201 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 6 TC 3 Z9 3 U1 0 U2 1 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 90 EP 93 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900019 PM 11770545 ER PT J AU Clowdsley, MS Wilson, JW Kim, MHY Singleterry, RC Tripathi, RK Heinbockel, JH Badavi, FF Shinn, JL AF Clowdsley, MS Wilson, JW Kim, MHY Singleterry, RC Tripathi, RK Heinbockel, JH Badavi, FF Shinn, JL TI Neutron environments on the Martian surface SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE neutrons; space radiation; Mars AB Radiation is a primary concern in the planning of a manned mission to Mars. Recent studies using NASA Langley Research Center's HZETRN space radiation transport code show that the low energy neutron fluence on the Martian surface is larger than previously expected. The upper atmosphere of Mars is exposed to a background radiation field made up of a large number of protons during a solar particle event and mixture of light and heavy ions caused by galactic cosmic rays at other times. In either case, these charged ions interact with the carbon and oxygen atoms of the Martian atmosphere through ionization and nuclear collisions producing secondary ions and neutrons which then interact with the atmospheric atoms in a similar manner. In the past, only these downward moving particles have been counted in evaluating the neutron energy spectrum on the surface. Recent enhancements in the HZETRN code allow for the additional evaluation of those neutrons created within the Martian regolith through the same types of nuclear reactions, which rise to the surface. New calculations using this improved HZETRN code show that these upward moving neutrons contribute significantly to the overall neutron spectrum for energies less than 10 MeV. C1 CNR, Washington, DC 20418 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. Coll William & Mary, Williamsburg, VA USA. Old Dominion Univ, Norfolk, VA USA. Christopher Newport Univ, Newport News, VA 23606 USA. NR 8 TC 12 Z9 13 U1 0 U2 1 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 94 EP 96 PG 3 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900020 PM 11770546 ER PT J AU Saganti, PB Zapp, EN Wilson, JW Cucinotta, FA AF Saganti, PB Zapp, EN Wilson, JW Cucinotta, FA TI Visual assessment of the radiation distribution in the ISS Lab module: Visualization in the human body SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE space radiation; international space station and destiny module; radiation transport; 3D-visualization AB The US Lab module of the International Space Station (ISS) is a primary working area where the crew members are expected to spend majority of their time. Because of the directionality of radiation fields caused by the Earth shadow, trapped radiation pitch angle distribution, and inherent variations in the ISS shielding, a model is needed to account for these local variations in the radiation distribution. We present the calculated radiation dose (rem/yr) values for over 3,000 different points in the working area of the Lab module and estimated radiation dose values for over 25,000 different points in the human body for a given ambient radiation environment. These estimated radiation dose values are presented in a three dimensional animated interactive visualization format. Such interactive animated visualization of the radiation distribution can be generated in near real-time to track changes in the radiation environment during the orbit precession of the ISS. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 15 TC 2 Z9 2 U1 0 U2 2 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 106 EP 112 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900024 PM 11770523 ER PT J AU Shavers, MR Cucinotta, FA Miller, J Zeitlin, C Heilbronn, L Wilson, JW Singleterry, RC AF Shavers, MR Cucinotta, FA Miller, J Zeitlin, C Heilbronn, L Wilson, JW Singleterry, RC TI Shielded heavy-ion environment linear detector (SHIELD): An experiment for the radiation and technology demonstration (RTD) mission SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE radiation shielding; cosmic radiation; heavy ion fragmentation ID 670A MEV NE-20; 510-MEV/NUCLEON FE-56; TRANSPORT-THEORY; FRAGMENTATION; DEPTH; WATER; POLYETHYLENE AB Radiological assessment of the many cosmic ion species of widely distributed energies requires the Use of theoretical transport models to accurately describe diverse physical processes related to nuclear reactions in spacecraft structures, planetary atmospheres and surfaces, and tissues. Heavy-ion transport models that were designed to characterize shielded radiation fields have been validated through comparison with data from thick-target irradiation experiments at particle accelerators. With the RTD Mission comes a unique opportunity to validate existing radiation transport models and guide the development of tools for shield design. For the first time, transport properties will be measured in free-space to characterize the shielding effectiveness of materials that are likely to be aboard interplanetary space missions. Target materials composed of aluminum, advanced composite spacecraft structure and other shielding materials, helium (a propellant) and tissue equivalent matrices will be evaluated. Large solid state detectors will provide kinetic energy and charge identification for incident heavy-ions and for secondary ions created in the target material. Transport calculations using the HZETRN model suggest that 8 g cm(-2) thick targets would be adequate to evaluate the shielding effectiveness during solar minimum activity conditions for a period of 30 days or more. C1 Loma Linda Univ, SN3 NASA Johnson Space Ctr, Houston, TX 77058 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NASA, Langley Res Ctr, MS 483, Hampton, VA 23681 USA. RI Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 7 TC 0 Z9 0 U1 0 U2 1 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 131 EP 132 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900030 PM 11770530 ER PT J AU Ponomarev, AL Cucinotta, FA Sachs, RK Brenner, DJ AF Ponomarev, AL Cucinotta, FA Sachs, RK Brenner, DJ TI Monte Carlo predictions of DNA fragment-size distributions for large sizes after HZE particle irradiation SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE polymer chromatin model; non-random DNA break-age ID DOUBLE-STRAND BREAKS; RADIATION; MODEL; CHROMOSOMES; POLYMER AB DSBs (double-strand breaks) produced by densely ionizing space radiation are not located randomly in the genome: recent data indicate DSB clustering along chromosomes. DSB clustering at large scales, from > 100 Mbp down to approximate to 2 kbp, is modeled using a Monte-Carlo algorithm. A random-walk model of chromatin is combined with a track model, that predicts the radial distribution of energy from an ion, and the RLC (randomly-located-clusters) formalism, in software called DNAbreak. This model generalizes the random-break-age model, whose broken-stick fragment-size distribution is applicable to low-LET radiation. DSB induction due to track interaction with the DNA volume depends on the radiation quality parameter 2. This dose-independent parameter depends only weakly on LET. Multi-track, high-dose effects depend on the cluster intensity parameter, proportional to fluence as defined by the RLC formalism. After lambda is determined by a numerical experiment, the model reduces to one adjustable parameter 2 The best numerical fits to the experimental data, determining 2, are obtained. The knowledge of lambda and 2 allows us to give biophysically based extrapolations of high-dose DNA fragment-size data to low doses or to high LETs. C1 NASA, Johnson Space Ctr, Houston, TX 77058 USA. Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. Columbia Univ, Ctr Radiolob Res, New York, NY 10032 USA. FU NCI NIH HHS [CA-77285, CA-49062, CA-24232]; NCRR NIH HHS [RR-11623]; NIEHS NIH HHS [ES-07361]; NIGMS NIH HHS [GM 57245] NR 12 TC 9 Z9 9 U1 0 U2 0 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 153 EP 156 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900037 PM 11771543 ER PT J AU Katz, R Cucinotta, FA Fromm, M Chambaudet, A AF Katz, R Cucinotta, FA Fromm, M Chambaudet, A TI Ion-kill dosimetry SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE ion-kill; biological dose; late effects; heavy ion therapy AB Unanticipated late effects in neutron and heavy ion therapy, not attributable to overdose, imply a qualitative difference between low and high LET therapy. We identify that difference as 'ion kill', associated with the spectrum of z/beta in the radiation field, whose measurement we label 'ion-kill dosimetry'. C1 Univ Nebraska, Lincoln, NE 68588 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Franche Comte, F-25030 Besancon, France. RI FROMM, Michel/E-3011-2012 NR 8 TC 1 Z9 1 U1 0 U2 0 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 164 EP 165 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900040 PM 11771546 ER PT J AU George, K Wu, H Willingham, V Cucinotta, FA AF George, K Wu, H Willingham, V Cucinotta, FA TI The effect of space radiation on the induction of chromosome damage SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE biodosimetry; chromosomes; high-LET; FISH ID ABERRATIONS; LYMPHOCYTES; PARTICLES; EXPOSURE AB To obtain information on the cytogenetic damage caused by space radiation, chromosome exchanges in lymphocytes from crewmembers of long-term Mir missions, and a shorter duration shuttle mission, were examined using fluorescence in situ hybridization. A significant increase in chromosomal aberrations was observed after the long duration flights. The ratio of aberrations identified as complex was higher post-flight for some crewmembers, which is thought to be an indication of exposure to high-LET radiation. Ground-based studies have shown that the frequency of aberrations measured post-flight could be influenced by a mitotic delay in cells damaged by high-LET radiation and this effect could lower biological dose estimates. To counteract this effect, prematurely condensed chromosome (PCC) spreads were collected. Frequencies of aberrations in PCC were compared with those in metaphase spreads. C1 Wyle Labs, Houston, TX USA. Kelsey Seybold, Houston, TX USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 9 TC 6 Z9 9 U1 1 U2 3 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 222 EP 225 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900061 PM 11776981 ER PT J AU Kawata, T Durante, M George, K Furusawa, Y Gotoh, E Takai, N Wu, H Cucinotta, FA AF Kawata, T Durante, M George, K Furusawa, Y Gotoh, E Takai, N Wu, H Cucinotta, FA TI Kinetics of chromatid break repair in G2-human fibroblasts exposed to low- and high-LET radiations SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE premature chromosome condensation; high-LET radiations; chromatid breaks and exchanges ID PREMATURE CHROMOSOME CONDENSATION; TUMOR-CELL LINES; ABERRATIONS; DAMAGE AB The purpose of this study is to determine the kinetics of chromatid break, rejoining following exposure to radiations of different quality. Exponentially growing human fibroblast cells AG1522 were irradiated with gamma -rays, energetic carbon (290 MeV/u), silicon (490 MeV/u) and iron (200 MeV/u, 600 MeV/u). Chromosomes were prematurely condensed using calyculin A. Prematurely condensed chromosomes were collected after several post-irradiation incubation times, ranging from 5 to 600 minutes, and the number of chromatid breaks and exchanges in G2 cells were scored. The relative biological effectiveness (RBE) for initial chromatid breaks per unit dose showed LET dependency having a peak at 55 keV/mum silicon (2.4) or 80 keV/mum carbon particles (2.4) and then decreased with increasing LET. The kinetics of chromatid break rejoining following low- or high-LET irradiation consisted of two exponential components. Chromatid breaks decreased rapidly after exposure, and then continued to decrease at a slower rate. The rejoining kinetics was similar for exposure to each type of radiation, although the rate of unrejoined breaks was higher for high-LET radiation. Chromatid exchanges were also formed quickly. C1 NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX USA. Univ Naples Federico II, Dept Phys, Naples, Italy. Wyle Labs, Houston, TX USA. Natl Inst Radiol Sci, Int Space Radiat Lab, Chiba 260, Japan. Natl Inst Infect Dis, Div Genet Resources, Tokyo, Japan. Kelsey Seybold Clin, Houston, TX USA. RI Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 8 TC 2 Z9 2 U1 0 U2 1 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 226 EP 228 PG 3 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900062 PM 11776982 ER PT J AU Wu, H George, K Willingham, V Cucinotta, FA AF Wu, H George, K Willingham, V Cucinotta, FA TI Comparison of chromosome aberration frequencies in pre- and postflight astronaut lymphocytes irradiated in vitro with gamma rays SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE radiation; space flight; chromosoma aberration ID DOUBLE-STRAND BREAKS; DNA; MICROGRAVITY; RADIATION; REPAIR; SPACE AB If radiosensitivity is altered in a microgravity environment, it will affect the accuracy of assessing astronauts' risk from exposure to space radiation. To investigate the effects of space flight on radiosensitivity, we exposed a crewmember's blood to gamma rays at doses ranging from 0 to 3 Gy and analyzed chromosome aberrations in mitotic lymphocytes. The blood samples were collected 10 days prior to an 8-day Shuttle mission, the day the flight returned, and 14 days after the flight. After exposure, lymphocytes were stimulated to grow in media containing phytohaemagglutinin (PHA) and mitotic cells were harvested for chromosome analysis using a fluorescence in situ hybridization (FISH) with whole chromosome specific probes. The dose response of total exchanges showed no changes in the radiosensitivity after the mission. C1 NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Kelsey Seybold Clin, Houston, TX 77058 USA. Wyle Labs, Houston, TX 77058 USA. NR 11 TC 8 Z9 9 U1 0 U2 2 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 229 EP 231 PG 3 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900063 PM 11776983 ER PT J AU Badhwar, GD AF Badhwar, GD TI Radiation measurements on the International Space Station SO PHYSICA MEDICA LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE radiation; space station; anthropomorphic phantom; risk AB The International Space Station (ISS) is becoming a reality with the docking of the Russian Service module (Zarya) with the Unity module (Zaveda). ISS will be in a nominal 51.65-degree inclination by 400 km orbit. This paper reviews the currently planned radiation measurements, which are in many instances, based on experiments previously flown on the Space Shuttle. Results to be expected based on Shuttle measurements are presented. C1 NASA, Johnson Space Ctr, Houston, TX 77058 USA. NR 5 TC 13 Z9 13 U1 1 U2 3 PU ISTITUTI EDITORIALI E POLGRAFICI INTERNAZIONALI PI PISA PA CASELLA POSTALE N 1, SUCCURSALE N 8, 56123 PISA, ITALY SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 287 EP 291 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900079 PM 11780621 ER PT J AU Cucinotta, FA AF Cucinotta, FA TI Once we know all the radiobiology we need to know, how can we use it to predict space radiation risks and achieve fame and fortune? SO PHYSICA MEDICA-EUROPEAN JOURNAL OF MEDICAL PHYSICS LA English DT Article; Proceedings Paper CT Joint Meeting of the 1st Interenational Workshop on Space Radiation Research/11th Annual NASA Space Radiation Health Investigators Workshop CY MAY 27-31, 2000 CL ARONA, ITALY SP Italian Space Agcy, European Sci Inst, NASA DE space radiation; radiation carcinogenesis; high-LET; HZE ions ID CARCINOGENESIS; CANCER; INSTABILITY; PARTICLES; EXPOSURE; CELL AB It has been over 40 years since occupational radiation exposures to NASA's astronauts began and more than 300 individuals have been exposed to low and intermediate doses of trapped protons and galactic cosmic rays (GCR). The International Space Station (ISS) will add substantially to this number and significantly increase average lifetime doses. We review these exposures in this report. After many years of investigation, the method used to assess risk have not changed significantly. However, molecular biology and genetics have made enormous progress in establishing the mechanisms of cancer formation, damage to the central nervous system, and individual variation in sensitivity to radiation. We discuss critical questions and possible new approaches to the prediction of risk from space radiation exposures. Experimental models can lead to testable theories that along with extensive biophysical and informatics approaches, will lead to fame and fortune by allowing for accurate projections of astronaut risks and for the development of biological countermeasures. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 35 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1120-1797 J9 PHYS MEDICA JI Phys. Medica PY 2001 VL 17 SU 1 BP 5 EP 12 PG 8 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 480LB UT WOS:000171461900004 PM 11770537 ER PT J AU Brown, GV Beiersdorfer, P Boyce, KR Gendreau, KC Gu, MF Gygax, J Kahn, SM Kelley, R Porter, FS Savin, DW Utter, SB AF Brown, GV Beiersdorfer, P Boyce, KR Gendreau, KC Gu, MF Gygax, J Kahn, SM Kelley, R Porter, FS Savin, DW Utter, SB TI Measurements of atomic parameters of highly charged ions for interpreting astrophysical spectra SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT 10th International Conference on the Physics of Highly Charged Ions (HCI 2000) CY JUL 30-AUG 03, 2000 CL CLARK KERR CAMPUS, BERKELEY, CALIFORNIA SP Amer Vacuum Soc, Lawrence Livermore Natl Lab HO CLARK KERR CAMPUS ID X-RAY-SPECTRUM; FE-XVII; LABORATORY MEASUREMENTS; ACTIVE-REGION; TRAP; SPECTROSCOPY; SPECTROMETER; EXCITATION AB High-resolution X-ray spectra obtained by the Chandra X-ray Observatory and the X-ray Multi-Mirror Mission put new demands on atomic data including line positions, excitation cross sections, and radiative rates of cosmically-abundant highly-charged ions. To address this need, we are performing measurements of the line emission from ions of cosmically abundant elements. The data are obtained at the LLNL Electron Beam Ion Trap and focus on cross sections for electron-impact excitation, dielectronic recombination, and resonance excitation as well as atomic structure measurements. We find that ratios of the electron-impact excitation cross sections of singlet and triplet levels are systematically different from the calculated values in the case of many highly charged ions. This, for example, has a profound impact on inferring optical depths from solar and stellar atmospheres. Moreover, new line identifications are presented that resolve some long-standing puzzles in the interpretation of solar data, and the importance of resonance contributions to the spectral emission is assessed. C1 Lawrence Livermore Natl Lab, Livermore, CA USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Columbia Univ, New York, NY USA. Swales & Associates, Beltsville, MD USA. RP Brown, GV (reprint author), Lawrence Livermore Natl Lab, Livermore, CA USA. RI Porter, Frederick/D-3501-2012; Savin, Daniel/B-9576-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; Savin, Daniel/0000-0002-1111-6610; NR 27 TC 6 Z9 7 U1 0 U2 1 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PY 2001 VL T92 BP 130 EP 134 DI 10.1238/Physica.Topical.092a00130 PG 5 WC Physics, Multidisciplinary SC Physics GA 460CK UT WOS:000170288100029 ER PT J AU Spann, JF Abbas, MM Venturini, CC Comfort, RH AF Spann, JF Abbas, MM Venturini, CC Comfort, RH TI Electrodynamic balance far studies of cosmic dust particles SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT International Topical Conference on Plasma Physics CY JUL 03-07, 2000 CL TRIESTE, ITALY ID NOCTILUCENT CLOUDS; SOLAR-SYSTEM; MST RADAR; PLASMAS; SPACE; MESOSPHERE; EMISSION; GRAINS; SIZE; MASS AB Knowledge of the formation and distribution of interstellar, interplanetary, and planetary dust grains, and their physical, chemical and optical characteristics provide valuable information about many issues dealing with the origin and formation of the solar system bodies, interplanetary and interstellar environments as well as various industrial processes. Understanding the microphysics of individual grains and their interaction with the surrounding environment is a key to properly model various conditions and interpret existing data. The theory and models of individual dust grains are well developed for environments that vary from dense planetary atmospheres to dusty plasmas to diffuse environments such as interplanetary space. However, experimental investigations of individual dust grains in equilibrium are less common, perhaps due to the difficulty of these experiments. Laboratory measurements of dust grains have primarily measured ensemble properties or transient properties of single grains. A technique developed in the 1950's for ion spectroscopy, generally referred to as a quadrupole trap has recently been employed as an electrodynamic balance to investigate single micron-sized dust grains and for atmospheric aerosol research. A description of the theoretical basis and the experimental setup of the electrodynamic balance being developed in our laboratory are given. This laboratory technique lends itself to many applications that relate to planetary atmospheres, heliospheric environments, pre-stellar and pre-planetary conditions, and industrial settings. We present results from some recent experiments carried out to investigate the equilibrium potential of dust grains exposed to far ultraviolet light or to an electron beam. Some future experiments using an electrodynamic balance to investigate the optical characteristics, and condensation process involving dust grains in various astrophysical environments are discussed. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Alabama, Ctr Space Plasma & Aeron Res, Huntsville, AL 35899 USA. RP NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 40 TC 19 Z9 19 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 EI 1402-4896 J9 PHYS SCRIPTA JI Phys. Scr. PY 2001 VL T89 BP 147 EP 153 DI 10.1238/Physica.Topical.089a00147 PG 7 WC Physics, Multidisciplinary SC Physics GA 402LT UT WOS:000166989200033 ER PT J AU Greenwood, JB Williams, ID Smith, SJ Chutjian, A AF Greenwood, JB Williams, ID Smith, SJ Chutjian, A TI X-ray emission from charge exchange of highly-charged ions in atoms and molecules SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT 10th International Conference on the Physics of Highly Charged Ions (HCI 2000) CY JUL 30-AUG 03, 2000 CL CLARK KERR CAMPUS, BERKELEY, CALIFORNIA SP Amer Vacuum Soc, Lawrence Livermore Natl Lab HO CLARK KERR CAMPUS ID ELECTRON-CAPTURE; CROSS-SECTIONS; COLLISIONS; PROJECTILES; MODEL AB Charge exchange followed by radiative stabilization are the main processes responsible for the recent observations of X-ray emission from comets in their approach to the Sun. A new apparatus was constructed at JPL to measure, in collisions of HCIs with atoms and molecules, (a) absolute cross sections for single and multiple charge exchange, and (b) normalized X-ray emission cross sections. The ions are produced by the JPL HCI Facility and passed through a neutral-gas target cell. The product charge states are analyzed by a retarding potential difference technique. Results are made absolute by measuring target pressure, and incident and product ion currents. X-rays emitted from the product ions are detected with a Ge solid-state detector having a resolution of approximately 100 eV. X-ray astronomy has taken major steps forward with the recent launch of the high-resolution satellites Chandra and Newton. The cross sections reported herein are essential for the development of the solar wind comet interaction models inspired by these observations. C1 Queens Univ Belfast, Dept Phys, Belfast BT7 1NN, Antrim, North Ireland. CALTECH, Jet Prop Lab, Atom & Mol Collis Team, Pasadena, CA 91109 USA. RP Greenwood, JB (reprint author), Queens Univ Belfast, Dept Phys, Belfast BT7 1NN, Antrim, North Ireland. RI Greenwood, Jason/L-4799-2014 NR 18 TC 3 Z9 3 U1 0 U2 1 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PY 2001 VL T92 BP 150 EP 152 DI 10.1238/Physica.Topical.092a00150 PG 3 WC Physics, Multidisciplinary SC Physics GA 460CK UT WOS:000170288100035 ER PT J AU Muller, HSP AF Muller, HSP TI The rotational spectrum of chlorine trifluoride, ClF3. Centrifugal distortion analysis, Cl nuclear magnetic shielding tensor, structure, and the harmonic force field SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-PROPERTIES; SPECTROSCOPY; QUADRUPOLE; FLUORIDE; CONSTANTS; BRF3; CIF3 AB The rotational spectrum of the T-shaped ClF3 was recorded for both Cl-35 and Cl-37 isotopomers in selected regions between 66 and 581 GHz. The observation of transitions involving J and K-a quantum numbers of up to 82 and 27, respectively, permitted the first centrifugal distortion analysis for this molecule. The quartic distortion constants were used together with data for the fundamental vibrations to derive harmonic force constants which were also calculated by means of ab initio methods. The harmonic force field and the rotational constants were employed to obtain ground state average (r(z)) structural parameters and to estimate the equilibrium structure (r(e)). Most of the rotational transitions showed resolved hyperfine splitting due to the Cl-35 or Cl-37 nucleus yielding, under consideration of previous data, accurate quadrupole coupling constants and, for the first time, nuclear spin-rotation coupling constants. While the former have been interpreted in terms of ionic bonding of the two different ClF bonds comparable to that in the ClF molecule, the latter were used to calculate nuclear magnetic shielding tensors. C1 Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Muller, HSP (reprint author), Univ Cologne, Inst Phys 1, Zulpicher Str 77, D-50937 Cologne, Germany. OI Mueller, Holger/0000-0002-0183-8927 NR 41 TC 6 Z9 6 U1 1 U2 2 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PY 2001 VL 3 IS 9 BP 1570 EP 1575 DI 10.1039/b100527h PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 420ZN UT WOS:000168035300002 ER PT S AU Greenleaf, JE AF Greenleaf, JE BE Shiraki, K Sagawa, S Yousef, MK TI Exercise stress: aging and thirst SO PHYSICAL FITNESS AND HEALTH PROMOTION IN ACTIVE AGING SE PROGRESS IN BIOMETEOROLOGY LA English DT Proceedings Paper CT International Symposium on Physical Fitness and Health Promotion in Active Aging CY OCT 25-27, 2000 CL KITAKYUSHU, JAPAN SP Univ Occupat & Environm Hlth, Soc Int Cooperat Occupat Hlth, Int Union Physiol Sci, Environm Physiol Commmiss DE fluid compartments; involuntary dehydration; salt intake; thirst; deconditoning ID PLASMA-VOLUME; DRINKING; DEHYDRATION; BEHAVIOR; MEN AB Consumption by humans of non-alcoholic fluids is one of the more important but lesser understood daily requirements for maintaining health and well-being, Total body water (TBW) volume is maintained by a balance between intake (mainly by drinking and water in food) and the major avenues of outgo including urinary, sweat, and insensible loss. The adverse effects of total body dehydration are many and include both physiological responses (hypovolemia and hyperosmotemia) associated with impaired thermoregulation, reduced exercise endurance, and orthostatic intolerance; and psychological responses including a sense of oppression, and impaired concentration and cognitive function. Many of these adverse effects, which occur during bed-rest (BR) deconditioning, are not only present but exaggerated in the aged. Absolute TBW, composed of the extracellular volume (ECV) plus the intracellular volume (ICV), is relatively stable but tends to decrease somewhat throughout adulthood. Voluntary fluid intake also decreases with age and may contribute to the decline of TBW. Ad libitum drinking in young men can be increased from 400 ml/hr to about 1000 ml/hr during an exercise-heat acclimation program which facilitates increases in ECV and TBW This acclimation-induced hyperdipsia does not occur in older (70 + yr) men and was accompanied by reduced plasma renin activity - angiotensin II and vasopressin (which can act as dipogens), and decreased subjective ratings of thirst that may be involved in attenuation of the acclimation-induced increase in drinking and body fluid volume. Many physiological responses involved with maintenance of body fluid balance such as body weight, thirst, involuntary fluid intake, TBW, ECV including plasma volume (PV), muscle atrophy, and fluid- electrolyte hormones that occur in the aged also occur in otherwise healthy people exposed to prolonged bed rest. Thus, bed rest may provide an appropriate model for studying effects of aging on thirst and drinking. C1 NASA, Ames Res Ctr, Gravitat Res Branch, Moffett Field, CA 94035 USA. RP Greenleaf, JE (reprint author), NASA, Ames Res Ctr, Gravitat Res Branch, Moffett Field, CA 94035 USA. NR 63 TC 0 Z9 0 U1 0 U2 0 PU BACKHUYS PUBLISHERS PI LEIDEN PA PO BOX 321, 2300 AH LEIDEN, NETHERLANDS SN 0923-0688 BN 90-5782-093-5 J9 PROG BIOMET PY 2001 VL 17 BP 91 EP 104 PG 14 WC Geriatrics & Gerontology; Sport Sciences SC Geriatrics & Gerontology; Sport Sciences GA BT17H UT WOS:000172148000008 ER PT J AU Moore, AW AF Moore, AW TI A review of currently available IGS network summaries SO PHYSICS AND CHEMISTRY OF THE EARTH PART A-SOLID EARTH AND GEODESY LA English DT Article; Proceedings Paper CT 2nd Network Workshop of the International GPS Service (IGS) CY JUL 10-12, 2000 CL OSLO, NORWAY AB All components of the International GPS Service (IGS) community have cause to seek metrics, reports, or summaries of the IGS network. Station personnel may wish to monitor the performance of their own stations, users need to select subnetworks of stations appropriate to a particular study, and analysts must understand station configurations to assure high quality results. With its role in day-to-day management and coordination of the IGS, the Central Bureau devises and maintains information appropriate to these needs on its information system, and also refers users to useful summaries maintained at IGS Data Centers and Analysis Centers. This paper reviews the content and possible usage of several network summaries that are located at or useful to the Central Bureau, with the intent of ensuring that the community has ready access to information that enables both assessment and improvement of network performance. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Int GPS Serv, Cent Bur, Pasadena, CA 91109 USA. RP Moore, AW (reprint author), CALTECH, Jet Prop Lab, Int GPS Serv, Cent Bur, 4800 Oak Grove Dr,Mail Stop 238-540, Pasadena, CA 91109 USA. NR 0 TC 5 Z9 6 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1895 J9 PHYS CHEM EARTH PT A JI Phys. Chem. Earth Pt. A-Solid Earth Geod. PY 2001 VL 26 IS 6-8 BP 591 EP 594 DI 10.1016/S1464-1895(01)00106-5 PG 4 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 436DM UT WOS:000168921300040 ER PT J AU Noll, C AF Noll, C TI Current status of and backup plans for flow of IGS data and products SO PHYSICS AND CHEMISTRY OF THE EARTH PART A-SOLID EARTH AND GEODESY LA English DT Article; Proceedings Paper CT 2nd Network Workshop of the International GPS Service (IGS) CY JUL 10-12, 2000 CL OSLO, NORWAY AB The IGS has been operational for nearly seven years. Recent changes in the data and products archived at the data centers prompts the review of the current IGS data flow and archiving methodologies. This presentation will outline the current structure at the IGS data centers, including the flow of both the daily and hourly data products, and will detail ideas for improvements to the data flow to ensure timely and consistent availability of IGS data and products, (C) 2001 Elsevier Science Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Noll, C (reprint author), NASA, Goddard Space Flight Ctr, Code 922, Greenbelt, MD 20771 USA. RI Noll, Carey/D-8884-2012 NR 3 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1895 J9 PHYS CHEM EARTH PT A JI Phys. Chem. Earth Pt. A-Solid Earth Geod. PY 2001 VL 26 IS 6-8 BP 595 EP 601 DI 10.1016/S1464-1895(01)00107-7 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 436DM UT WOS:000168921300041 ER PT J AU Noll, C Dube, M AF Noll, C Dube, M TI The IGS global data center at the CDDIS - An update SO PHYSICS AND CHEMISTRY OF THE EARTH PART A-SOLID EARTH AND GEODESY LA English DT Article; Proceedings Paper CT 2nd Network Workshop of the International GPS Service (IGS) CY JUL 10-12, 2000 CL OSLO, NORWAY AB The Crustal Dynamics Data Information System (CDDIS) has served as a global data center for the International GPS Service (IGS) since its start in June 1992, providing on-line access to data from over 175 sites on a daily basis. This paper will present information about the GPS and GLONASS data and products archive at the CDDIS. General information about the system and its support of other international space geodesy services (the ILRS, IVS, IGLOS-PP, and DPE) will also be discussed. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Raytheon Informat Technol & Sci Serv, Greenbelt, MD 20770 USA. RP Noll, C (reprint author), NASA, Goddard Space Flight Ctr, Code 922, Greenbelt, MD 20771 USA. RI Noll, Carey/D-8884-2012 NR 1 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1895 J9 PHYS CHEM EARTH PT A JI Phys. Chem. Earth Pt. A-Solid Earth Geod. PY 2001 VL 26 IS 6-8 BP 603 EP 604 DI 10.1016/S1464-1895(01)00108-9 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 436DM UT WOS:000168921300042 ER PT J AU Zumberge, JF Gendt, G AF Zumberge, JF Gendt, G TI The demise of selective availability and implications for the International GPS Service SO PHYSICS AND CHEMISTRY OF THE EARTH PART A-SOLID EARTH AND GEODESY LA English DT Article; Proceedings Paper CT 2nd Network Workshop of the International GPS Service (IGS) CY JUL 10-12, 2000 CL OSLO, NORWAY AB Early on May 2, 2000, selective availability (SA) - the intentional dithering of clocks on GPS satellites - was terminated. The amplitude of variations in transmitter clocks, formerly tens of meters, was reduced by orders of magnitude. These clocks are now much more predictable, with the possibility that the International GPS Service (IGS) can produce, in addition to real-time orbits, real-time clocks that are of significantly higher quality than those in the broadcast ephemeris. Furthermore, the meaning of high in "high rate ground network" to support low-Earth-orbiter (LEO) missions needs to be re-examined. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Geoforsch Zentrum, Potsdam, Germany. RP Zumberge, JF (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NR 0 TC 10 Z9 14 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1895 J9 PHYS CHEM EARTH PT A JI Phys. Chem. Earth Pt. A-Solid Earth Geod. PY 2001 VL 26 IS 6-8 BP 637 EP 644 DI 10.1016/S1464-1895(01)00113-2 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 436DM UT WOS:000168921300047 ER PT J AU Clemmons, JH Pfaff, RF AF Clemmons, JH Pfaff, RF TI The collision meter: An experimental technique to measure charged-neutral interactions and gas composition in the upper atmosphere SO PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE LA English DT Article AB A method of exploring the upper atmosphere through measurements of charged-neutral particle collisions is described. The method utilizes a charged particle beam which is injected into space from an in-situ probe and returns to the probe under its gyromotion about the ambient magnetic field. Measurements of the attenuation of the re turned beam provide direct information on the collisional cross sections between the beam particles and the ambient medium. The method is discussed and expected measurements displayed and evaluated. In addition to providing new information on collision processes in the upper atmosphere, it is shown that this method has the potential for returning very accurate determinations of the densities of the major neutral gas species, including atomic oxygen. Initial in-situ experiments and directions for extension and further use are discussed, (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Aerospace Corp, El Segundo, CA 90245 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Clemmons, JH (reprint author), Aerospace Corp, El Segundo, CA 90245 USA. RI Pfaff, Robert/F-5703-2012; OI Pfaff, Robert/0000-0002-4881-9715; Clemmons, James/0000-0002-5298-5222 NR 11 TC 1 Z9 1 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1917 J9 PHYS CHEM EARTH PT C JI Phys. Chem. Earth Pt. C-Solar-Terr. Planet. Sci. PY 2001 VL 26 IS 4 BP 247 EP 252 DI 10.1016/S1464-1917(00)00116-1 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 415FZ UT WOS:000167711400001 ER PT J AU Grebowsky, JM Gervin, JC AF Grebowsky, JM Gervin, JC TI Geospace electrodynamic connections SO PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE LA English DT Article AB As part of NASA's Solar Terrestrial Probe (STP) line of spacecraft, the planned Geospace Electrodynamic Connections (GEC) mission is designed to finally explore in depth the intricacies of electrodynamic coupling processes in the lower ionosphere, where magnetospheric processes couple with the thermosphere. It is currently envisioned as a 4-spacecraft (identically instrumented) mission, which will measure all relevant in situ plasma and neutral atmosphere parameters with the option of including remote observations for a wider perspective. The parking orbits will be 200X2000 km with weeklong dipping campaigns planned down below 130 km where the neutral atmosphere begins to dominate the dissipation of plasma energy and momentum. Each spacecraft will carry hundreds of kilograms of propellant to enable deep dipping campaigns and to have the maneuverability to investigate a broad spectrum of relevant electrodynamic coupling scale sizes. Thruster firings will be used to provide different spacings between spacecraft - either along a common pearls-on-a-string configuration, or by separating the planes of the orbits in local time, or by relative changes in the latitude of the argument of perigee. GEC has the exciting potential for resolving many of the uncertainties in our understanding of the ionosphere as an inseparable part of the electrodynamic physics chain connecting the sun's magnetoplasma with the Earth's upper atmosphere. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Grebowsky, JM (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Grebowsky, Joseph/I-7185-2013 NR 5 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1917 J9 PHYS CHEM EARTH PT C JI Phys. Chem. Earth Pt. C-Solar-Terr. Planet. Sci. PY 2001 VL 26 IS 4 BP 253 EP 258 DI 10.1016/S1464-1917(00)00117-3 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 415FZ UT WOS:000167711400002 ER PT J AU Prasad, SS Aikin, A Poulet, G Stolte, S AF Prasad, SS Aikin, A Poulet, G Stolte, S TI New chemistry of the atmosphere SO PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE LA English DT Editorial Material C1 Goddard Space Flight Ctr, Greenbelt, MD USA. Univ Orleans, CNRS, LPCE, F-45067 Orleans, France. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1917 J9 PHYS CHEM EARTH PT C JI Phys. Chem. Earth Pt. C-Solar-Terr. Planet. Sci. PY 2001 VL 26 IS 7 BP 465 EP 465 DI 10.1016/S1464-1917(01)00032-0 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 450YE UT WOS:000169771800001 ER PT J AU Aikin, AC AF Aikin, AC TI Isotope identification in NO as a chemical tracer in the middle atmosphere SO PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE LA English DT Article; Proceedings Paper CT 25th General Assembly of the European-Geophysical-Society CY APR 24-29, 2000 CL NICE, FRANCE SP European Geophys Soc ID STRATOSPHERIC NITROUS-OXIDE; NITRIC-OXIDE; 2-DIMENSIONAL MODEL; N2O; FRACTIONATION; RATIOS; OZONE; CYCLE AB The nitrogen isotope ratio of middle atmosphere nitrogen oxide is predicted as a function of altitude. Nitrogen oxides originate photochemically either from stratospheric nitrous oxide reacting with O(D-1) or in the mesosphere and thermosphere from direct dissociation of N-2 and ionization-initiated reactions involving O-2 and N-2. During its formation process, N2O acquires a nitrogen isotopic composition of N isotopes different than N-2. Photodissociation within the stratosphere also modifies the proportion of isotopes. Reaction of stratospheric NO with 4 produces NO2, which when photodissociated yields NO depleted in N-15 relative to NO2 in laboratory air. The value of delta (NO)-N-15 in the stratosphere is -100 parts per thousand. In the altitude region between 50 and 65 km, NO is transformed into NO2 and then returned to NO by reaction of NO2 with O and by NO2 photodissociation These reactions determine the isotopic makeup of NO. Above 65 km, nitric oxide is produced by local ionization processes and gas phase photochemical reactions involving N-2 and excited O-2. These processes determine the isotopic composition of NO in the upper mesosphere and thermosphere. Here delta (NO)-N-15 is 0 parts per thousand. Air transported into the mesosphere above 65 km will reflect the NO isotopic values of the region below, while mesospheric NO transported below 65 km will not be distinguishable from NO originating in the stratosphere. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Aikin, AC (reprint author), Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. NR 26 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1917 J9 PHYS CHEM EARTH PT C JI Phys. Chem. Earth Pt. C-Solar-Terr. Planet. Sci. PY 2001 VL 26 IS 7 BP 527 EP 532 DI 10.1016/S1464-1917(01)00041-1 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 450YE UT WOS:000169771800010 ER PT S AU Li, JZ Cheung, SH Ning, CZ AF Li, JZ Cheung, SH Ning, CZ BE Arakawa, Y Blood, P Osinski, M TI Theory and simulation of self- and mutual-diffusion of carrier density and temperature in semiconductor lasers SO PHYSICS AND SIMULATION OF OPTOELECTRONIC DEVICES IX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Physics and Simulation of Optoelectronic Devices IX CY JAN 22-26, 2001 CL SAN JOSE, CA SP SPIE DE semiconductor laser; inhomogeneity; carrier diffusion; plasma heating effect; VCSEL ID SURFACE-EMITTING LASERS; GAAS QUANTUM WELLS; EXCITED SEMICONDUCTORS; BLOCH EQUATIONS; DYNAMICS AB Carrier diffusion and thermal conduction play a fundamental role in the operation of high-power, broad-area semiconductor lasers. Restricted geometry, high pumping level and dynamic instability lead to inhomogeneous spatial distribution of plasma density, temperature, as well as light field, due to strong light-matter interaction. Thus, modeling and simulation of such optoelectronic devices rely on detailed descriptions of carrier dynamics and energy transport in the system. A self-consistent description of lasing and heating in large-aperture, spatially-inhomogencous edge- or surface-emitting lasers (VCSELs) require coupled diffusion equations for carrier density and temperature. In this paper., we derive such equations from the Boltzmann transport equation for the carrier distributions. The derived self- and mutual-diffusion coefficients are in general nonlinear functions of carrier density and temperature including many-body interactions. We study the effects of many-body interactions on these coefficients, as well as the nonlinearity of these coefficients for large-area VCSELs. The effects of mutual diffusions on carrier and temperature distributions in gain-guided VCSELs will be also presented. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Li, JZ (reprint author), NASA, Ames Res Ctr, M-S T27A-1, Moffett Field, CA 94035 USA. NR 22 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3961-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4283 BP 267 EP 274 DI 10.1117/12.432574 PG 4 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BT06P UT WOS:000171845100027 ER PT S AU Goorjian, PM Ning, CZ Agrawal, GP AF Goorjian, PM Ning, CZ Agrawal, GP BE Arakawa, Y Blood, P Osinski, M TI Spatial dynamics of VCSEL arrays SO PHYSICS AND SIMULATION OF OPTOELECTRONIC DEVICES IX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Physics and Simulation of Optoelectronic Devices IX CY JAN 22-26, 2001 CL SAN JOSE, CA SP SPIE DE VCSELs; laser arrays; spatial dynamics; computational modeling; optoelectronics; laser optics ID TRANSVERSE-MODE DYNAMICS; SEMICONDUCTOR-LASERS; SIMULATION AB Numerical simulations of the spatial dynamics of the light output of two-dimensional arrays of VCSELs are presented. The cases presented include square and circular arrays of nine elements. For both configurations the spacing between elements is varied to study the effects on the interaction between elements. In addition, the effects of index guiding on the supermodes of the arrays will be shown. It was found that, with only a small amount of index guiding, the interactions between elements of the VCSEL array are effectively eliminated for all spacings between elements. The time evolutions of the spatial profiles of the laser intensity and carrier density are obtained by solving the Effective Semiconductor Bloch-Maxwell equations by a finite-difference algorithm. The algorithm can handle devices with multiple active regions of any shapes or pattern. There is no a priori assumption about the type or number of modes. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Goorjian, PM (reprint author), NASA, Ames Res Ctr, MS 202A-1, Moffett Field, CA 94035 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3961-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4283 BP 287 EP 292 DI 10.1117/12.432576 PG 4 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BT06P UT WOS:000171845100029 ER PT J AU Bandyopadhyay, S Svizhenko, S AF Bandyopadhyay, S Svizhenko, S TI What has scattering got to do with noise in nanostructures SO PHYSICS OF LOW-DIMENSIONAL STRUCTURES LA English DT Article ID QUANTUM WIRES AB A counter-intuitive relationship between scattering and noise in nano-structures is explored. It is shown that in the case of quasi one-dimensional structures, increase in scattering is actually attended by a decrease in noise. The physical origin of this surprising result is elucidated. C1 Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU V S V CO. LTD PI MOSCOW PA BOX 11, 105523 MOSCOW, RUSSIA SN 0204-3467 J9 PHYS LOW-DIMENS STR JI Phys. Low-Dimens. Struct. PY 2001 VL 9-10 BP 161 EP 168 PG 8 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 522FY UT WOS:000173886400016 ER PT S AU Keys, AS Fork, RL Nelson, TR Ehret, JE Van Nostrand, JE AF Keys, AS Fork, RL Nelson, TR Ehret, JE Van Nostrand, JE BE Lalanne, P TI Characterization of a multilayered dielectric transmissive phase modulator SO PHYSICS, THEORY, AND APPLICATIONS OF PERIODIC STRUCTURES IN OPTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Physics, Theory, and Applications of Periodic Structures in Optics CY AUG 01-02, 2001 CL SAN DIEGO, CA SP SPIE DE thin film stacks; optical beam steering; phase modulator; diffractive optics; optical interference coatings; optical bandpass filter; gallium arsenide; aluminum arsenide ID ARRAY AB We describe a multilayered dielectric stack configuration designed specifically for use as a transmissive phase modulator for broadband optical signals. Applications for this device range from full aperture wavefront correction to nonmechanical beam steering arrays for free space optical communication links. Our implementation employs alternating GaAs and AlAs layers of varying thickness on a GaAs substrate to create a bandpass region of high average transmission in the near infrared. Within this transmission bandpass, the phase component of the complex transmission coefficient varies in a near-linear fashion with respect to wavelength. The transmission bandpass is designed to have a bandwidth of 21.0 am (or 6.3THz frequency bandwidth) and to have an edge-to-edge relative phase change of greater than 4pi radians. Modification of the stack materials' optical properties causes the transmission profile to shift spectrally, resulting in a phase modulation for specific bands of transmitted frequencies. Our broadband phase modulator imparts nearly a full-cycle of phase modulation with low loss and low group velocity dispersion. A sample comprising 91 alternating layers has been fabricated to exhibit the bandpass properties required for optical signal phase modulation. We experimentally characterize the sample using an interferometer and spectrometer to measure the spectral transmission and relative phase profiles and to assess the relative phase modulation in response to a variable angle of incidence. We compare the experimental data to computational predictions and discuss the results. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Keys, AS (reprint author), NASA, George C Marshall Space Flight Ctr, Mail Stop SD72, Huntsville, AL 35812 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4152-X J9 P SOC PHOTO-OPT INS PY 2001 VL 4438 BP 96 EP 107 DI 10.1117/12.451482 PG 4 WC Optics SC Optics GA BT90L UT WOS:000174395400011 ER PT J AU Wilson, T AF Wilson, T TI Theory, phenomenology, and 'who ordered that?' SO PHYSICS TODAY LA English DT Letter C1 NASA, Houston, TX 77058 USA. RP Wilson, T (reprint author), NASA, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD JAN PY 2001 VL 54 IS 1 BP 13 EP 13 PG 1 WC Physics, Multidisciplinary SC Physics GA 388UB UT WOS:000166200500003 ER PT J AU McKay, CP Coustenis, A Samuelson, RE Lemmon, MT Lorenz, RD Cabane, M Rannou, P Drossart, P AF McKay, CP Coustenis, A Samuelson, RE Lemmon, MT Lorenz, RD Cabane, M Rannou, P Drossart, P TI Physical properties of the organic aerosols and clouds on Titan SO PLANETARY AND SPACE SCIENCE LA English DT Review ID VOYAGER-1 RADIO-OCCULTATION; INFRARED OBSERVATIONS; OPTICAL-PROPERTIES; LABORATORY INVESTIGATIONS; VERTICAL-DISTRIBUTION; GENERAL-CIRCULATION; AGGREGATE PARTICLES; HYPOTHESIZED OCEAN; GEOMETRIC ALBEDO; LOWER ATMOSPHERE AB Titan's haze is optically thick in the visible, with an optical depth at 0.5 mum of about three. The haze varies with latitude in a seasonal cycle and has a detached upper layer. Microphysical models, photochemical models, and laboratory simulations all imply that the production rate of the haze is in the range of 0.5-2 x 10(-14) g cm(-2) s(-1). Given the rate of sedimentation, the total mass loading is about 250 mg m(-2). The transparency of the haze is high for wavelengths above 1 mum because the haze material becomes almost purely scattering and the optical depth decreases with increasing wavelength. The particles in the main haze deck are probably fractal in structure with an equivalent volume radius of 0.2 mum. The haze material is organic and, if similar to laboratory tholin, has a C/N ratio in the range of 2-4 and a C/H ratio of about unity. The haze significantly affects the thermal balance of Titan, causing an antigreenhouse effect that cools the surface by 9 K. Titan's faintly banded appearance suggests strong zonal winds in the lower stratosphere. Condensate clouds of ethane or methane, if present, are thin, patchy, or transient. Stratospheric clouds of condensed nitriles and (possibly) hydrocarbons appear to be associated with, though not contained entirely in, the polar shadow, suggesting abundances may vary with the season. Precipitating condensate particles from the stratosphere probably act as nucleating centers for the formation and rapid growth of methane ice particles in the troposphere, where the gas phase appears to be highly supersaturated Once formed, fallout times for these hailstones are similar to 2 h or less. Melting, and possible subsequent fragmentation of methane raindrops should occur at similar to 12 km and below. Almost complete evaporation should occur just above the surface. A thin residue of ethane-enriched fog particles would then slowly settle to the surface, steadily modifying an existing surface or subsurface residue of liquid hydrocarbons. The optical properties of the haze in the 1 to 3 mum spectral region and the implications for the visibility of the surface are probably the most pressing current research questions. Other key questions include the nature of the high altitude detached haze layer, altitude and seasonal changes in composition of the haze, the role of haze particles as condensation nuclei for clouds, and the nature of any condensate clouds. Published by Elsevier Science Ltd. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Observ Paris Meudon, DESPA, F-92195 Meudon, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Arizona, LPL, Tucson, AZ 85721 USA. Univ Paris 06, Serv Aeron, F-75252 Paris, France. RP McKay, CP (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RI Lemmon, Mark/E-9983-2010; RANNOU, Pascal/I-9059-2012; Lorenz, Ralph/B-8759-2016 OI Lemmon, Mark/0000-0002-4504-5136; Lorenz, Ralph/0000-0001-8528-4644 NR 137 TC 117 Z9 117 U1 0 U2 22 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD JAN PY 2001 VL 49 IS 1 BP 79 EP 99 DI 10.1016/S0032-0633(00)00051-9 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 392JC UT WOS:000166407100010 ER PT S AU Forbes, JM Hagan, ME Bougher, SW Hollingsworth, JL AF Forbes, JM Hagan, ME Bougher, SW Hollingsworth, JL BE Cravens, TE Nagy, AF TI Kelvin wave propagation in the upper atmospheres of Mars and Earth SO PLANETARY IONOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT C3 2/D3 8 Symposium of COSPAR Scientific Commission C held at the 33rd COPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Inst Space Astronut Sci, Comm Space Res ID GENERAL-CIRCULATION MODEL; MIGRATING SOLAR TIDES; MARTIAN ATMOSPHERE; THERMAL TIDES; GLOBAL SURVEYOR; MEAN WINDS; MIDDLE AB The propagation characteristics of a diurnal Kelvin wave (DKW) in the atmosphere of Mars and a 3-day Kelvin wave in the terrestrial atmosphere are compared and interpreted for Northern Hemisphere summer conditions (Ls = 90 and July, respectively). Significant horizontal wind and temperature perturbations are shown to accompany these oscillations in the thermospheres, of both planets: similar to 10-40 ms(-1) and 10-25 K on Earth and 20-70 ms(-1) and 10-30 K on Mars. Molecular dissipation on both planets serves to latitudinally broaden the thermospheric response, and to induce meridional wind maxima at the poles. On Earth, mean zonal winds asymmetric about the equator are found to locally (in altitude) distort the latitudinal shapes of the Kelvin wave fields by coupling,into modes which tend to remain confined to the level of excitation, and which are equatorially trapped. On Mars the first asymmetric eastward propagating mode with vertical wavelength of about 60 km is very efficiently induced by the asymmetric zonal mean winds in the middle atmosphere; this wave component propagates well into the thermosphere and accounts for much global asymmetry seen in the wave fields. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. Natl Ctr Atmospher Res, Boulder, CO 80303 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. NASA, Ames Res Ctr, SJSUF, Moffett Field, CA 94035 USA. RP Forbes, JM (reprint author), Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. RI Hagan, Maura/C-7200-2008; Bougher, Stephen/C-1913-2013 OI FORBES, JEFFREY/0000-0001-6937-0796; Hagan, Maura/0000-0002-8866-7429; Bougher, Stephen/0000-0002-4178-2729 NR 23 TC 10 Z9 11 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 11 BP 1791 EP 1800 DI 10.1016/S0273-1177(01)00286-1 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT29L UT WOS:000172545300001 ER PT S AU Pesnell, WD Grebowsky, JM AF Pesnell, WD Grebowsky, JM BE Cravens, TE Nagy, AF TI Meteoric ions in planetary ionospheres SO PLANETARY IONOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT C3 2/D3 8 Symposium of COSPAR Scientific Commission C held at the 33rd COPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Inst Space Astronut Sci, Comm Space Res ID NIGHTSIDE IONOSPHERE; METALLIC-IONS; ATMOSPHERE; MAGNESIUM; NEPTUNE AB Solar system debris, in the form of meteoroids, impacts every planet. The flux, relative composition and speed of the debris at, each planet depends on the planet's size and location in the solar system. Ablation of this debris by the atmosphere leaves behind metal atoms. During the ablation process metallic ions are formed by impact ionization. For small inner solar system planets, including Earth, this source of ionization is typically small compared to either photoionization or charge exchange with ambient molecular ions. For Earth, the atmosphere above the main deposition region absorbs the spectral lines capable of ionizing the major metallic atoms (Fe and Mg) so that charge exchange with ambient ions is the dominant cause of ionization. Within the carbon dioxide atmosphere of Mars (and possibly Venus), photoionization is important in determining the ion density. For a heavy planet like Jupiter, far from the sun, impact ionization of ablated neutral atoms by impacts with molecules becomes a prominent source of ionization due to the gravitational acceleration to high incident speeds. We will describe the processes and location and extent of metal ion layers for Mars, Earth and Jupiter, concentrating on flagging the uncertainties in the models at the present, time. This is an important problem, because low altitude ionosphere layers for the planets, particularly at night, probably consist predominantly of metallic ions. Comparisons with Earth will be used to illustrate the differing processes in the three planetary atmospheres. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Nomad Res Inc, Arnold, MD 21012 USA. NASA, Goddard Space Flight Ctr, Lab Extraterrestrial Phys, Greenbelt, MD 20771 USA. RP Pesnell, WD (reprint author), Nomad Res Inc, 795 Scarborough Court, Arnold, MD 21012 USA. RI Pesnell, William/D-1062-2012; Grebowsky, Joseph/I-7185-2013 OI Pesnell, William/0000-0002-8306-2500; NR 22 TC 11 Z9 11 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 11 BP 1807 EP 1814 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT29L UT WOS:000172545300003 ER PT S AU Crider, D Acuna, M Connerney, J Mitchell, D Lin, R Cloutier, P Reme, H Mazelle, C Brain, D Ness, N Bauer, S AF Crider, D Acuna, M Connerney, J Mitchell, D Lin, R Cloutier, P Reme, H Mazelle, C Brain, D Ness, N Bauer, S BE Cravens, TE Nagy, AF TI Magnetic field draping around Mars: Mars global surveyor results SO PLANETARY IONOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT C3 2/D3 8 Symposium of COSPAR Scientific Commission C held at the 33rd COPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Inst Space Astronut Sci, Comm Space Res ID IONOSPHERE AB We investigate the contribution of the radial component of the magnetic field in the solar wind interaction with Mars. We use Mars Global Surveyor Magnetometer and Electron Reflectometer data during the Science Phasing Orbits to gain a qualitative understanding of the magnitude of the radial magnetic field from the solar wind draping around the dayside of Mars. Using only data far away, from the strong crustal magnetic sources, we find that the angle the magnetic field makes to the horizontal within the martian ionosphere has an average closer to zero than that outside the ionosphere. However, we find a much larger spread in angles inside the ionosphere. In addition, we find that the angle of inclination increases with increasing altitude and local time, but more spatial coverage is needed to quantify these relationships. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA USA. Rice Univ, Houston, TX 77251 USA. Ctr Etud Spatiale Rayonnements, Toulouse, France. Univ Colorado, Boulder, CO 80309 USA. Univ Delaware, Bartol Res Inst, Newark, DE USA. Graz Univ, Graz, Austria. RP Crider, D (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. RI connerney, john/I-5127-2013; Hurley, Dana/F-4488-2015; OI Hurley, Dana/0000-0003-1052-1494; Bauer, Siegfried/0000-0003-4213-2047 NR 4 TC 14 Z9 15 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 11 BP 1831 EP 1836 DI 10.1016/S0273-1177(01)00333-7 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT29L UT WOS:000172545300006 ER PT S AU Chassefiere, E Forget, F Hourdin, F Vial, F Reme, H Mazelle, C Vignes, D Sauvaud, JA Blelly, PL Toublanc, D Berthelier, JJ Cerisier, JC Chanteur, G Duvet, L Menvielle, M Lilensten, J Witasse, O Touboul, P Quemerais, E Bertaux, JL Hulot, G Cohen, Y Lognonne, P Barriot, JP Balmino, G Blanc, M Pinet, P Parrot, M Trotignon, JG Moncuquet, M Bougeret, JL Issautier, K Lellouch, E Meyer, N Sotin, C Grasset, O Barlier, F Berger, C Tarits, P Dyment, J Breuer, D Spohn, T Patzold, M Sperveslage, K Gough, P Buckley, A Szego, K Sasaki, S Smrekar, S Lyons, D Acuna, M Connerney, J Purucker, M Lin, R Luhmann, J Mitchell, D Leblanc, F Johnson, R Clarke, J Nagy, A Young, D Bougher, S Keating, G Haberle, R Jakosky, B Hodges, R Parmentier, M Waite, H Bass, D AF Chassefiere, E Forget, F Hourdin, F Vial, F Reme, H Mazelle, C Vignes, D Sauvaud, JA Blelly, PL Toublanc, D Berthelier, JJ Cerisier, JC Chanteur, G Duvet, L Menvielle, M Lilensten, J Witasse, O Touboul, P Quemerais, E Bertaux, JL Hulot, G Cohen, Y Lognonne, P Barriot, JP Balmino, G Blanc, M Pinet, P Parrot, M Trotignon, JG Moncuquet, M Bougeret, JL Issautier, K Lellouch, E Meyer, N Sotin, C Grasset, O Barlier, F Berger, C Tarits, P Dyment, J Breuer, D Spohn, T Patzold, M Sperveslage, K Gough, P Buckley, A Szego, K Sasaki, S Smrekar, S Lyons, D Acuna, M Connerney, J Purucker, M Lin, R Luhmann, J Mitchell, D Leblanc, F Johnson, R Clarke, J Nagy, A Young, D Bougher, S Keating, G Haberle, R Jakosky, B Hodges, R Parmentier, M Waite, H Bass, D BE Cravens, TE Nagy, AF TI Scientific objectives of the DYNAMO mission SO PLANETARY IONOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT C3 2/D3 8 Symposium of COSPAR Scientific Commission C held at the 33rd COPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Inst Space Astronut Sci, Comm Space Res ID MARS GLOBAL SURVEYOR; SOLAR-WIND; ISOTOPIC FRACTIONATION; MARTIAN ATMOSPHERE; MAGNETIC-FIELD; HOT OXYGEN; VENUS; HYDROGEN; SPECTROMETER; ENVIRONMENTS AB DYNAMO is a small Mars orbiter planned to be launched in 2005 or 2007, in the frame of the NASA/ CNES Mars exploration program. It is aimed at improving gravity and magnetic field resolution, in order to better understand the magnetic, geologic and thermal history of Mars, and at characterizing current atmospheric escape, which is still poorly constrained. These objectives are achieved by using a low periapsis orbit, similar to the one used by the Mars Global Surveyor spacecraft during its aerobraking phases. The proposed periapsis altitude for DYNAMO of 120-130 km, coupled with the global distribution of periapses to be obtained during one Martian year of operation, through about 5000 low passes, will produce a magnetic/gravity field data set with approximately five times the spatial resolution of MGS. Additional data on the internal structure will be obtained by mapping the electric conductivity. Low periapsis provides a unique opportunity to investigate the chemical and dynamical properties of the deep ionosphere, thermosphere, and the interaction between the atmosphere and the solar wind, therefore atmospheric escape, which may have played a crucial role in removing atmosphere and water from the planet. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Paris 06, IPSL, Lab Meteorol Dynam, F-75252 Paris 05, France. Ctr Etud Spatiale Rayonnements, Toulouse, France. IPSL, Ctr Etude Environm Terrestre & Planetaires, Paris, France. Lab Planetol Grenoble, Grenoble, France. Off Natl Etudes & Rech Aerospatiales, Paris, France. IPSL, Serv Aeronomie, Paris, France. Inst Phys Globe, Paris, France. Observ Midi Pyrenees, Toulouse, France. Lab Phys & Chim Environm, Orleans, France. Observ Paris, Dept Etudes Spatiales, Paris, France. Lab Planetol & Geodynam, Nantes, France. Observ Cote Azur, CERGA, Grasse, France. Univ Bretagne Occidentale, Plouzane, France. Inst Planetol, Munster, Germany. Inst Geophys & Meteorol, Cologne, Germany. Univ Sussex, Brighton BN1 9RH, E Sussex, England. Hungarian Acad Sci, Budapest, Hungary. Univ Tokyo, Geol Inst, Tokyo, Japan. Jet Prop Lab, Pasadena, CA USA. Goddard Space Flight Ctr, Greenbelt, MD USA. Space Sci Lab, Berkeley, CA USA. Univ Virginia, Charlottesville, VA USA. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Arizona, Tucson, AZ USA. George Washington Univ, Hampton, VA USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Colorado, Boulder, CO 80309 USA. Univ Texas, Dallas, TX 75230 USA. Brown Univ, Providence, RI 02912 USA. SW Res Inst, San Antonio, TX USA. RP Chassefiere, E (reprint author), Univ Paris 06, IPSL, Lab Meteorol Dynam, 4 Pl Jussieu,BP 99, F-75252 Paris 05, France. RI ipgp, Laboratoire geoscien/F-8471-2010; Hulot, Gauthier/A-5627-2011; Dyment, Jerome/A-6788-2011; IPGP, Geosciences Marines/F-8780-2010; Bougher, Stephen/C-1913-2013; Lognonne, Philippe/F-8846-2010; connerney, john/I-5127-2013; Clarke, John/C-8644-2013 OI Bougher, Stephen/0000-0002-4178-2729; NR 39 TC 5 Z9 5 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 11 BP 1851 EP 1860 DI 10.1016/S0273-1177(01)00338-6 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT29L UT WOS:000172545300009 ER PT S AU Hartle, RE Intriligator, DS Grebowsky, JM AF Hartle, RE Intriligator, DS Grebowsky, JM BE Cravens, TE Nagy, AF TI Ionospheric flow and escape of ions from Titan and Venus SO PLANETARY IONOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT C3 2/D3 8 Symposium of COSPAR Scientific Commission C held at the 33rd COPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Inst Space Astronut Sci, Comm Space Res ID PLASMA OBSERVATIONS; VOYAGER-1; HYDROGEN; TAIL AB Knowledge gained from measurements and models is used to study the high-speed plasmas interacting with the atmospheres and ionospheres of Titan and Venus. Considering the similarities of the interactions, comparative analysis is used to support the interpretations of observations made at each body. Ionospheric flow, inferred to exist by analysis of measurements made from the Pioneer Venus Orbiter, supports the interpretation of similar flow in the ionosphere of Titan. The concept of cold ion escape from the ionosphere of Venus is supported by the Voyager 1 observation that cold ions escape down the magnetic tail of Titan. Pickup O+ ion energy distributions observed at their source in the ionosheath of Venus are shown to be influenced by finite gyroradius effects. The signatures of such effects are expected to be retained as the ions move into the wakes of Titan and Venus. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Carmel Res Ctr, Santa Monica, CA 90406 USA. RP Hartle, RE (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Grebowsky, Joseph/I-7185-2013 NR 14 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 11 BP 1869 EP 1874 DI 10.1016/S0273-1177(01)00276-9 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT29L UT WOS:000172545300011 ER PT S AU Verigin, MI Kotova, GA Slavin, J Szabo, A Kessel, M Safrankova, J Nemecek, Z Gombosi, TI Kabin, K Shugaev, F Kalinchenko, A AF Verigin, MI Kotova, GA Slavin, J Szabo, A Kessel, M Safrankova, J Nemecek, Z Gombosi, TI Kabin, K Shugaev, F Kalinchenko, A BE Dougherty, M Menietti, JD TI Analysis of the 3-D shape of the terrestrial bow shock by INTERBALL/MAGION 4 observations SO PLANETARY MAGNETOSPHERES SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT D3 1/C3 3 Symposium of COSPAR Scientific Commission D held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Amer Geophys Union, Comm Space Res ID MAGNETIC-FIELD ORIENTATION; SOLAR-WIND FLOW; MACH NUMBERS; MAGNETOPAUSE; MAGNETOSPHERE; POSITION; SIMULATIONS; DIMENSIONS AB Location and shape of the terrestrial bow shock are analyzed using MAGION 4 (sub satellite of INTERBALL 1) crossings of this boundary and upstream solar wind parameters measured by the WIND spacecraft. Different crossing points were mapped to the Sun - Earth line and to the terminator plane using an analytical model of the planetary bow shock previously developed for the Martian bow shock investigation. Analysis of the subsolar bow shock position as a function of Alfvenic Mach number (M(a)) revealed fine effect that this boundary tends to approach the Earth when M(a) is decreasing for field-aligned flow of the solar wind, while for non field-aligned flow the bow shock moves away from the planet. Asymmetry of the terrestrial bow shock in the terminator plane is found for non field-aligned flow with anisotropic Friedrichs diagrams. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Space Res Inst, Moscow 117997, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Charles Univ Prague, CR-18000 Prague 8, Czech Republic. Univ Michigan, Ann Arbor, MI 48109 USA. Moscow MV Lomonosov State Univ, Fac Phys, Moscow 119899, Russia. RP Verigin, MI (reprint author), Space Res Inst, Ul Profsoyuznaya 84-32,GSP-7, Moscow 117997, Russia. RI Slavin, James/H-3170-2012; Gombosi, Tamas/G-4238-2011 OI Slavin, James/0000-0002-9206-724X; Gombosi, Tamas/0000-0001-9360-4951 NR 19 TC 24 Z9 26 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES-SERIES PY 2001 VL 28 IS 6 BP 857 EP 862 DI 10.1016/S0273-1177(01)00502-6 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT60K UT WOS:000173494400004 ER PT S AU Verigin, MI Kotova, GA Remizov, AP Szego, K Tatrallyay, M Slavin, J Rosenbauer, H Livi, S Riedler, W Schwingenschuh, K Zhang, TL AF Verigin, MI Kotova, GA Remizov, AP Szego, K Tatrallyay, M Slavin, J Rosenbauer, H Livi, S Riedler, W Schwingenschuh, K Zhang, TL BE Dougherty, M Menietti, JD TI Evidence of the influence of equatorial Martian crustal magnetization on the position of the planetary magnetotail boundary by Phobos 2 data SO PLANETARY MAGNETOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT D3 1/C3 3 Symposium of COSPAR Scientific Commission D held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Amer Geophys Union, Comm Space Res ID MARS GLOBAL SURVEYOR; WIND RAM PRESSURE; SOLAR-WIND; MAG/ER EXPERIMENT; BOW SHOCK; MAGNETOSPHERE; MAGNETOPAUSE; FIELDS AB In addition to earlier found variations of the Martian magnetotail thickness as a function of the solar wind ram pressure, succeeding analysis of the magnetotail boundary crossings by Phobos 2 orbiter revealed modulation of magnetopause positions by planetary crustal magnetization. It was shown that magnetic anomalies mostly influence the magnetotail thickness when they are approaching the terminator region due to planetary rotation. The areographic position of the equatorial regions of Mars, which efficiently increase planetary magnetotail thickness, corresponds to strongly magnetized regions recently mapped by the Mars Global Surveyor. Local enhancement of the magnetotail thickness due to non-uniform crustal magnetization can be as high as 500-1000 km. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Moscow Space Res Inst, Moscow 117810, Russia. KFKI, Res Inst Particle & Nucl Phys, Budapest, Hungary. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Max Planck Inst Aeron, Katlenburg Lindau, Germany. Space Res Inst, Graz, Austria. RP Verigin, MI (reprint author), Moscow Space Res Inst, Profsoyuznaya 84-32, Moscow 117810, Russia. RI Slavin, James/H-3170-2012 OI Slavin, James/0000-0002-9206-724X NR 18 TC 6 Z9 6 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 28 IS 6 BP 885 EP 889 DI 10.1016/S0273-1177(01)00510-5 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT60K UT WOS:000173494400009 ER PT S AU Santos-Costa, D Sault, R Bourdarie, S Boscher, D Bolton, S Thorne, R Leblanc, Y Dulk, G Levin, S Gulkis, S AF Santos-Costa, D Sault, R Bourdarie, S Boscher, D Bolton, S Thorne, R Leblanc, Y Dulk, G Levin, S Gulkis, S BE Dougherty, M Menietti, JD TI Synchrotron emission images from three-dimensional modeling of the Jovian electron radiation belts SO PLANETARY MAGNETOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT D3 1/C3 3 Symposium of COSPAR Scientific Commission D held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP Amer Geophys Union, Comm Space Res AB Images of Jupiter's synchrotron emission give a global view of the inner Jovian magnetosphere: they are very useful to analyze both the Salammbo-3D results (a three-dimensional modeling of the Jovian radiation belts (Beutier and Boscher, 1995) and the relative importance of prominent physical processes occurring in this region. Here we present comparisons between model synchrotron emission images highlighting specific processes deduced from our 3-D simulation, and observations made with the VLA in May 1997 at 20 cm. Both realistic and unrealistic models are presented to judge of the importance of few physical processes. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Off Natl Etud & Rech Aerosp, DESP, F-31055 Toulouse, France. CSIRO, Australia Telescope Natl Facil, Epping, NSW 2121, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90095 USA. Observ Paris, Dept Rech Spatiale, F-92195 Meudon, France. Univ Colorado, Boulder, CO 80309 USA. RP Santos-Costa, D (reprint author), Off Natl Etud & Rech Aerosp, DESP, 2 Av Edouard Belin, F-31055 Toulouse, France. NR 15 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 28 IS 6 BP 915 EP 918 DI 10.1016/S0273-1177(01)00527-0 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT60K UT WOS:000173494400014 ER PT B AU Sahai, R AF Sahai, R BE Szczerba, R Gorny, SK TI HST imaging of proto-planetary nebulae and very young planetary nebulae - Towards a new understanding of their formation SO POST-AGB OBJECTS AS A PHASE OF STELLAR EVOLUTION SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT Workshop on Post-AGB Objects as a Phase of Stellar Evolution CY JUL 05-07, 2000 CL TORUN, POLAND SP Polish State Comm Sci Res ID BIPOLAR PROTOPLANETARY NEBULA; SPACE-TELESCOPE OBSERVATIONS; CIRCUMSTELLAR ENVELOPES; AGB STARS; DISCOVERY; EMISSION; JETS; EVOLUTION AB With the advent of the Wide Field Planetary Camera2 (WFPC2) onboard the Hubble Space Telescope (HST) in Dec 1993, a growing number of young planetary and proto-planetary nebulae (PNe and PPNe) have been imaged with unprecedented high angular resolution and dynamic range. These objects represent the last phases of the evolution of intermediate-mass (similar to1-8 MD) stars. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Sahai, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS183-900, Pasadena, CA 91109 USA. NR 42 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-7145-3 J9 ASTROPHYS SPACE SC L PY 2001 VL 265 BP 53 EP 63 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT46X UT WOS:000173071400008 ER PT B AU Ryan, MA Herman, JA Fleurial, JP Williams, RM Snyder, GJ Daly, D Huang, CK Caillat, T Borshchevsky, A AF Ryan, MA Herman, JA Fleurial, JP Williams, RM Snyder, GJ Daly, D Huang, CK Caillat, T Borshchevsky, A BE Ryan, MA Surampudi, S Jain, M TI Electrochemical deposition of semiconductors for thermoelectric devices SO POWER SOURCES FOR THE NEW MILLENNIUM, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Power Sources for the New Millennium CY OCT 22-27, 2000 CL PHOENIX, AZ SP Electrochem Soc Energy Tecchnol & Ind Electrolysis Div, Electrochem Soc Electrochem Engn Div AB Thermoelectric microgenerators are an approach to power conversion which can deliver milliwatts to watts of power at a few to several tens of Volts. The fabrication of micrometer-scale thermoelectric elements from bulk materials is limited mechanically; however, electrochemical deposition allows fabrication of tens of thousands of elements simultaneously at scales as small as several nanometers. In order for thermoelectric microgenerators to be fabricated, approaches to the electrochemical deposition of the semiconductors used must be developed. Depositions must be stoichiometric, dense and have surface roughness less than a few micrometers. Compounds studied include Bi2Te3 and alloys such as Bi2-xSbxTe3 for near room temperature operation, and PbTe and CoSb3 for higher temperature operation. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ryan, MA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Snyder, G. Jeffrey/E-4453-2011; Snyder, G/I-2263-2015 OI Snyder, G. Jeffrey/0000-0003-1414-8682; NR 7 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-289-3 J9 ELEC SOC S PY 2001 VL 2000 IS 22 BP 229 EP 234 PG 6 WC Electrochemistry; Energy & Fuels SC Electrochemistry; Energy & Fuels GA BX93U UT WOS:000186891500025 ER PT B AU Whitacre, JF West, WC Ratnakumar, BV Brandon, E Surampudi, S AF Whitacre, JF West, WC Ratnakumar, BV Brandon, E Surampudi, S BE Ryan, MA Surampudi, S Jain, M TI Low process temperature nanocrystalline LiCoO2e thin film cathodes SO POWER SOURCES FOR THE NEW MILLENNIUM, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Power Sources for the New Millennium CY OCT 22-27, 2000 CL PHOENIX, AZ SP Electrochem Soc Energy Tecchnol & Ind Electrolysis Div, Electrochem Soc Electrochem Engn Div ID RECHARGEABLE LITHIUM BATTERIES; COBALT AB The highest capacity thin film cathode layers (LiCoO2) typically require an annealing step of 700 degreesC. Since this high temperature is not compatible with Si device technology or flexible polymer substrates, the development of a low process temperature (less than or equal to300 degreesC) cathode layer has been undertaken. LiCoO2 thin films were RF sputter deposited and subsequently incorporated into thin film batteries. A variety of deposition and post-deposition parameters were varied in an effort to optimize film microstructure and content. Film composition and microstructure were examined using a variety of techniques including x-ray diffraction using synchrotron radiation. It was found that LiCoO2 could be deposited at room temperature in a nanocrystalline state with a strong (104) out of plane texture and a high degree of lattice distortion. By heating these layers to 300 degreesC, the grain size is significantly increased while lattice distortion is eliminated. Cycling data reveals that the heating step increases cell capacity to near theoretical values (at lower discharge currents) while significantly improving both the rate capability and discharge voltage. C1 CALTECH, Jet Prop Lab, Ctr Integrated Space Microsyst, Electrochem Technol Grp, Pasadena, CA 91109 USA. RP Whitacre, JF (reprint author), CALTECH, Jet Prop Lab, Ctr Integrated Space Microsyst, Electrochem Technol Grp, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 14 TC 8 Z9 9 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-289-3 J9 ELEC SOC S PY 2001 VL 2000 IS 22 BP 257 EP 265 PG 9 WC Electrochemistry; Energy & Fuels SC Electrochemistry; Energy & Fuels GA BX93U UT WOS:000186891500029 ER PT J AU Elmustafa, AA Lagally, MG AF Elmustafa, AA Lagally, MG TI Flexural-hinge guided motion nanopositioner stage for precision machining: finite element simulations SO PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY LA English DT Article DE flexural-hinge; nanopositioner; precision machining; piezoelectric actuator; finite element simulations ID COMPENSATION; TOOL AB Finite element analysis has been used to study the behavior of flexural-hinge guided- motion nanopositioning stages designed for use in precision machining. The primary criteria of such nanopositioners are a high stiffness and large load carrying ability. Both static loading and modal frequency analysis an performed. A procedure is developed by which we can redesign and reanalyze the model while simulating the performance of the nanopositioner. Modification of dimensions enables us to control and optimize resonant frequency, displacement, stresses, and force to be applied to the hinges to achieve the desired response of the positioner and the positioner motion. (C) 2000 Elsevier Science Inc. All rights reserved. C1 PIEZOMAX Technol Inc, Madison, WI 53719 USA. RP Elmustafa, AA (reprint author), NASA, Langley Res Ctr, Ctr Adv Computat Technol UVA, Hampton, VA 23681 USA. NR 10 TC 35 Z9 44 U1 0 U2 6 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0141-6359 J9 PRECIS ENG JI Precis. Eng.-J. Int. Soc. Precis. Eng. Nanotechnol. PD JAN PY 2001 VL 25 IS 1 BP 77 EP 81 DI 10.1016/S0141-6359(00)00058-1 PG 5 WC Engineering, Multidisciplinary; Engineering, Manufacturing; Nanoscience & Nanotechnology; Instruments & Instrumentation SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation GA 392JY UT WOS:000166409000010 ER PT S AU Altunin, V AF Altunin, V BE Cohen, RJ Sullivan, WT TI Protecting space-based radio astronomy SO PRESERVING THE ASTRONOMICAL SKY SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 196th Symposium of the International-Astronomical-Union held in conjunction with UNISPACE III CY JUL 12-16, 1999 CL VIENNA, AUSTRIA SP Int Astron Union ID MICROWAVE BACKGROUND ANISOTROPY; MISSION; VLBI; TELESCOPE AB This paper outlines some of the radio frequency interference issues related to radio astronomy performed with space-based radio telescopes. Radio frequency interference that threatens radio astronomy observations from the surface of Earth will also degrade observations with space-based radio telescopes. However, any resulting interference could be different than for ground-based telescopes due to several factors. Space radio astronomy observations significantly enhance studies in different areas of astronomy. Several space radio astronomy experiments for studies in low-frequency radio astronomy, space VLBI, the cosmic microwave background and the submillimetre wavelengths have flown already. The first results from these missions have provided significant breakthroughs in our understanding of the nature of celestial radio radiation. Radio astronomers plan to deploy more radio telescopes in Earth orbit, in the vicinity of the L-2 Sun-Earth Lagrangian point, and, in the more distant future, in the shielded zone of the Moon. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Altunin, V (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 27 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-078-1 J9 IAU SYMP PY 2001 IS 196 BP 324 EP 334 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35Q UT WOS:000175748300056 ER PT B AU Caillat, T Fleurial, JP Snyder, J Borshchevsky, A AF Caillat, T Fleurial, JP Snyder, J Borshchevsky, A BE Hanada, S Zhong, Z Nam, SW Wright, RN TI Development of high efficiency thermoelectric materials and unicouples for power generation applications SO PRICM 4: FORTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, VOLS I AND II LA English DT Proceedings Paper CT 4th Pacific Rim International Conference on Advanced Materials and Processing (PRICM4) CY DEC 11-15, 2001 CL HONOLULU, HI SP Japan Inst Met, Chinese Soc Met, Korean Inst Met & Mat, Minerals, Met & Mat Soc, Iketani Sci & Technol Fdn, USN, Off Naval Res Int Field Off, Asian Off Aerosp Res & Dev, USA Res Off Far E ID SKUTTERUDITES AB The efficiency of current solid state thermoelectric coolers and power generators is primarily limited by the relatively low efficiency of the thermoelectric materials used to fabricate these devices. A brief review of state-of-the-art thermoelectric materials both for cooling and power generation is given. A considerable amount of research has been performed over the last decade to develop new efficient thermoelectric materials. Promising results have been obtained and new materials with superior thermoelectric properties have been discovered. Some of the new materials under development are introduced in this paper. Highly efficient, segmented thermoelectric unicouples incorporating advanced thermoelectric materials with superior thermoelectric figures of merit are currently being developed at the Jet Propulsion Laboratory (JPL). These segmented unicouples include a combination of state-of-the-art thermoelectric materials based on Bi2Te3 and novel p-type Zn4Sb3, p-type CeFe4Sb(12)-based alloys and n-type CoSb3-based alloys developed at JPL. The maximum predicted thermal to electrical efficiency is about 15% for a hot-side temperature of 975K and a cold-side temperature of about 300K. Several unicouples with different segmentation are currently being fabricated and tested at JPL. Experimental thermal to electrical efficiency values of about 10% have been demonstrated. These advanced unicouples could be used in a variety of power generation applications including waste heat recovery and space. These applications are briefly reviewed. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Caillat, T (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 277-207, Pasadena, CA 91109 USA. RI Snyder, G. Jeffrey/E-4453-2011 OI Snyder, G. Jeffrey/0000-0003-1414-8682 NR 19 TC 0 Z9 0 U1 0 U2 7 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-404-8 PY 2001 BP 2165 EP 2168 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA BV26R UT WOS:000178391600549 ER PT B AU Fleurial, JP Snyder, GJ Ryan, MA Huang, CK Borshchevsky, A Herman, JA Caillat, T AF Fleurial, JP Snyder, GJ Ryan, MA Huang, CK Borshchevsky, A Herman, JA Caillat, T BE Hanada, S Zhong, Z Nam, SW Wright, RN TI Thermoelectric microdevices for on-chip power generation and cooling SO PRICM 4: FORTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, VOLS I AND II LA English DT Proceedings Paper CT 4th Pacific Rim International Conference on Advanced Materials and Processing (PRICM4) CY DEC 11-15, 2001 CL HONOLULU, HI SP Japan Inst Met, Chinese Soc Met, Korean Inst Met & Mat, Minerals, Met & Mat Soc, Iketani Sci & Technol Fdn, USN, Off Naval Res Int Field Off, Asian Off Aerosp Res & Dev, USA Res Off Far E DE thermoelectric; microdevice; energy conversion; electrochemistry; cooling; power generation ID CONDUCTIVITY AB Solid-state thermoelectric devices used in power generation and active cooling applications have demonstrated attractive characteristics such as long life, the absence of moving parts or emissions, low maintenance and high reliability. hi spite of a large number of potential civilian and military applications, their use has been severely limited due to their relatively low energy conversion efficiency and high development costs. To broaden the field of thermoelectrics, higher performance materials and devices are needed. Much larger values of the materials' dimensionless thermoelectric figure of merit ZT are theoretically possible and the investigation of radically new compounds and the development of nanostructured materials (superlattices, nanowires and quantum dots) are new approaches that have recently resulted in promising discoveries. Also, new concepts and microfabrication techniques are currently being developed based on thick and thin film processes and are expected to remove some of the physical limitations of bulk devices and result in significant design and performance improvement. Key challenges associated with novel thermoelectric microdevices and on-going efforts at the Jet-Propulsion Laboratory are reviewed. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Fleurial, JP (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Snyder, G. Jeffrey/E-4453-2011; Snyder, G/I-2263-2015 OI Snyder, G. Jeffrey/0000-0003-1414-8682; NR 20 TC 1 Z9 1 U1 0 U2 2 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-404-8 PY 2001 BP 2937 EP 2940 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA BV26R UT WOS:000178391600744 ER PT S AU Jadaan, O Nemeth, N Powers, L Palko, J Baker, E AF Jadaan, O Nemeth, N Powers, L Palko, J Baker, E BE Soboyejo, ABO Orisamolu, IR Soboyejo, WO TI Time-dependent reliability of ceramic components under transient loads SO PROBABILISTIC METHODS IN FATIGUE AND FRACTURE SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT Symposium on Probabilistic Methods in Fatigue and Fracture held at the ASME Winter Annual Meeting CY NOV, 2000 CL ORLANDO, FLORIDA SP ASME DE failure; fatigue; reliability; transient; Weibull ID FRACTURE AB Present capabilities of the NASA CARES/Life code include probabilistic life prediction of ceramic components subjected to fast fracture, slow crack growth (stress corrosion), and cyclic fatigue failure modes. Currently, this code has the capability to compute the time-dependent reliability of ceramic structures subjected to simple time-dependent loading. For example, in slow crack growth (SCG) type failure conditions CARES/Life can handle the cases of sustained and linearly increasing time-dependent loads, while for cyclic fatigue applications various types of repetitive constant amplitude loads can be accounted for. In real applications applied loads are rarely that simple, but rather vary with time in more complex ways such as, for example, engine start up, shut down, and dynamic and vibrational loads, In addition, when a given component is subjected to transient environmental and or thermal conditions, the material properties also vary with time. The objective of this paper is to demonstrate a methodology capable of predicting the time-dependent reliability of components subjected to transient thermomechanical loads that takes into account the change in material response with time. In this paper, the dominant delayed failure mechanism is assumed to be SCG. This capability has been added to the NASA CARES/Life (Ceramic Analysis and Reliability Evaluation of Structures/Life) code, which has also been modified to have the ability of interfacing with commercially available FEA codes executed for transient load histories. An example involving a ceramic exhaust valve subjected to combustion cycle loads is presented to demonstrate the viability of this methodology and the CARES/Life program. C1 Univ Wisconsin, Platteville, WI 53818 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Case Western Reserve Univ, Cleveland, OH 44106 USA. Connecticut Reserve Technol, Cleveland, OH USA. Cleveland State Univ, Cleveland, OH 44115 USA. RP Jadaan, O (reprint author), Univ Wisconsin, Platteville, WI 53818 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 1013-9826 BN 0-87849-872-9 J9 KEY ENG MAT PY 2001 VL 200 BP 213 EP 228 PG 16 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BS10N UT WOS:000168666800010 ER PT B AU Nandra, K AF Nandra, K BE Peterson, BM Polidan, RS Pogge, RW TI X-ray variability of AGN and its relationship to the Optical/UV SO PROBING THE PHYSICS OF ACTIVE GALACTIC NUCLEI BY MULTIWAVELENGTH MONITORING, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Workshop on Probing the Physics of Active Galactic Nuclei by Multiwavelength Monitoring CY JUN 20-22, 2000 CL GREENBELT, MD ID ACTIVE GALACTIC NUCLEI; BROAD-LINE REGION; SEYFERT-1 GALAXIES; ACCRETION-DISK; ULTRAVIOLET VARIABILITY; SPECTRAL VARIABILITY; ASCA OBSERVATIONS; MAGNETIC FLARES; BLACK-HOLES; CONTINUUM AB Some models predict a connection between the X-ray emission of active galactic nuclei (AGN) and lower-energy radiation in the optical and ultraviolet (OUV), which can be tested by multiwaveband observations. Strong correlations are observed within the optical/UV band and between the extreme ultraviolet (EUV) and X-rays. The relationship between the X-ray and OUV fluxes is much less clear, with some recent intensive campaigns showing little or no correlation. Furthermore, the X-rays usually show very rapid variations which are not seen in the OUV. We show, however: that before drawing conclusions about possible emission mechanisms, it is important to consider the X-ray spectrum and its variability in detail. The current data strongly favor thermal Comptonization as the origin of the X-rays, with the OUV acting: as the seed photons. Reprocessing: is not ruled out as a mechanism for producing relatively rapid variations in OUV flux, and these can feed back into the Compton upscattering process. The most rapid variability in the X-ray band is almost certainly unrelated to the OUV seed photons, however, and probably originates intrinsically in the the X-ray corona. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Nandra, K (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 662, Greenbelt, MD 20771 USA. NR 51 TC 4 Z9 4 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-055-2 J9 ASTR SOC P PY 2001 VL 224 BP 167 EP 181 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BS48S UT WOS:000170040700016 ER PT B AU Hartman, RC Thompson, DJ Villata, M Raiteri, CM Sobrito, G Ostorero, L De Francesco, G Tosti, G Kurtanidze, O Nikolashvili, M Takalo, L Sillanpaa, A Koskimies, H Pursimo, T Rekola, R Heidt, J Wagner, S Carini, MT Noble, JC Balonek, TJ Miller, HR Ferrara, EC McFarland, JP Wilson, JW AF Hartman, RC Thompson, DJ Villata, M Raiteri, CM Sobrito, G Ostorero, L De Francesco, G Tosti, G Kurtanidze, O Nikolashvili, M Takalo, L Sillanpaa, A Koskimies, H Pursimo, T Rekola, R Heidt, J Wagner, S Carini, MT Noble, JC Balonek, TJ Miller, HR Ferrara, EC McFarland, JP Wilson, JW BE Peterson, BM Polidan, RS Pogge, RW TI A possible Optical/Gamma-ray short-term correlation in 3C 279 SO PROBING THE PHYSICS OF ACTIVE GALACTIC NUCLEI BY MULTIWAVELENGTH MONITORING, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Workshop on Probing the Physics of Active Galactic Nuclei by Multiwavelength Monitoring CY JUN 20-22, 2000 CL GREENBELT, MD ID GAMMA-RAY; VARIABILITY; BLAZARS AB Evidence is presented for possible day-scale correlations between R-band optical fluxes and gamma -rays detected by the EGRET instrument on the Compton Gamma-Ray Observatory during 1999 January 20 through February 2. At that time, the gamma -ray time variations appear to have lagged behind those in optical by about 3.5 days. Similar monitoring about 13 months later yielded no apparent correlation between the gamma -ray and optical fluxes. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hartman, RC (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Thompson, David/D-2939-2012 OI Thompson, David/0000-0001-5217-9135 NR 5 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-055-2 J9 ASTR SOC P PY 2001 VL 224 BP 249 EP 254 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BS48S UT WOS:000170040700021 ER PT B AU Polidan, RS Peterson, BM AF Polidan, RS Peterson, BM BE Peterson, BM Polidan, RS Pogge, RW TI The Kronos MIDEX concept SO PROBING THE PHYSICS OF ACTIVE GALACTIC NUCLEI BY MULTIWAVELENGTH MONITORING, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Workshop on Probing the Physics of Active Galactic Nuclei by Multiwavelength Monitoring CY JUN 20-22, 2000 CL GREENBELT, MD AB We describe an Explorer-class mission concept designed for long-term, high time-resolution multiwavelength monitoring of active galactic nuclei and accretion-driven Galactic sources. We outline the basic characteristics of the science instruments and the proposed high-Earth orbit. C1 NASA, Goddard Space Flight Ctr, Space Sci Directorate, Greenbelt, MD 20771 USA. RP Polidan, RS (reprint author), NASA, Goddard Space Flight Ctr, Space Sci Directorate, Code 600, Greenbelt, MD 20771 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-055-2 J9 ASTR SOC P PY 2001 VL 224 BP 479 EP 482 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BS48S UT WOS:000170040700041 ER PT S AU Pappa, RS Giersch, LR Quagliaroli, JM AF Pappa, RS Giersch, LR Quagliaroli, JM GP SPIE SPIE TI Photogrammetry of a 5m inflatable space antenna with consumer digital cameras SO PROCEEDINGS OF IMAC-XIX: A CONFERENCE ON STRUCTURAL DYNAMICS, VOLS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 19th International Model Analysis Conference CY FEB 05-08, 2001 CL KISSIMMEE, FL SP Soc Expt Mech Inc AB This paper discusses photogrammetric measurements of a Sm-diameter inflatable space antenna using four Kodak DC290 (2.1 megapixel) digital cameras. The study had two objectives: 1) Determine the photogrammetric measurement precision obtained using multiple consumer-grade digital cameras and 2) Gain experience with new commercial photogrammetry software packages, specifically PhotoModeler Pro from Eos Systems, Inc. The paper covers the eight steps required using this hardware/software combination. The baseline data set contained four images of the structure taken from various viewing directions. Each image came from a separate camera. This approach simulated the situation of using multiple time-synchronized cameras, which will be required in future tests of vibrating or deploying ultra-lightweight space structures. With four images, the average measurement precision for more than 500 points on the antenna surface was less than 0.020 inches in-plane and approximately 0.050 inches out-of-plane. C1 NASA, Langley Res Ctr, Struct Dynam Branch, Hampton, VA 23681 USA. RP Pappa, RS (reprint author), NASA, Langley Res Ctr, Struct Dynam Branch, Hampton, VA 23681 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-72-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4359 BP 550 EP 560 PG 5 WC Engineering, Civil; Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS11E UT WOS:000168694300086 ER PT S AU Levine, MB White, C AF Levine, MB White, C GP SPIE SPIE TI Microdynamic analysis for establishing nanometric stability requirements of jointed precision space structures SO PROCEEDINGS OF IMAC-XIX: A CONFERENCE ON STRUCTURAL DYNAMICS, VOLS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 19th International Model Analysis Conference CY FEB 05-08, 2001 CL KISSIMMEE, FL SP Soc Expt Mech Inc AB This paper presents a framework for microdynamic analysis - analyzing a structure for nonlinear dynamic behavior in the nanometric regime - and illustrates how these analyses might be used in structural design and system verification. A categorization of the different microdynamic analyses as a function of frequency response and complexity of structural analysis is established. Analysis methods appropriate for some of these categories are outlined. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Levine, MB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,M-S 157-316, Pasadena, CA 91109 USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-72-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4359 BP 1395 EP 1401 PG 3 WC Engineering, Civil; Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS11E UT WOS:000168694300214 ER PT B AU Su, J Harrison, JS St Clair, T AF Su, J Harrison, JS St Clair, T BE Streiffer, SK Gibbons, BJ Tsurumi, T TI Novel polymeric elastomers for actuation SO PROCEEDINGS OF THE 2001 12TH IEEE INTERNATIONAL SYMPOSIUM ON APPLICATIONS OF FERROELECTRICS, VOLS I AND II LA English DT Proceedings Paper CT 12th IEEE International Symposium on Applications of Ferroelectrics (ISAF 2000) CY JUL 21-AUG 02, 2000 CL HONOLULU, HI SP IEEE, Ultrason, Ferroelectr & Frequency Control Soc ID ELECTROSTRICTIVE RESPONSE; POLYURETHANE ELASTOMER; DIELECTRICS AB Efficient actuators that are lightweight, high performance and compact are needed to support telerobotic requirements for future NASA missions. A new class of electrostrictive polymeric materials has been developed in our recent work. The materials are graft elastomers that exhibit not only large electric field-induced strain (4%) but also a relatively high mechanical modulus (560 MPa). Consequently, the materials offer high actuation output power for enhanced actuation performance. In addition to the promising electromechanical properties, the materials are readily processable by conventional methods. By combining this graft elastomer with a piezoelectric polymer, polyvinylidene fluoride (PVDF), an electrostrictive-piezoelectric multifunctional polymer blend system has also been developed. This multifunctional system exhibits a significantly high piezoelectric strain coefficient, d(31), of 12 pC/N while the electric field-induced strain is enhanced due to the combination of the mechanisms of electrostriction and piezoelectricity. Experimental results of the electric field-induced strain in the polymeric elastomers and the electrostrictive-piezoelectric polymer blend system will be discussed. A prototype bending actuator using the materials is also presented. C1 NASA Langley Res Ctr, ICASE, Hampton, VA 23681 USA. RP Su, J (reprint author), NASA Langley Res Ctr, ICASE, Hampton, VA 23681 USA. NR 8 TC 1 Z9 2 U1 1 U2 5 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5941-0 PY 2001 BP 811 EP 814 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS91S UT WOS:000171370100177 ER PT S AU Kimiaghalam, B Homaifar, A Sayarrodsari, B AF Kimiaghalam, B Homaifar, A Sayarrodsari, B GP AACC AACC AACC TI An application of Model Predictive Control for a shipboard crane SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC DE Model Predictive Control; crane control; nonlinear control; discrete control AB Designing an effective controller for shipboard cranes by means of analytical methods is too complex, because of their highly nonlinear equations of motion. In this work we formulate the swinging suppression problem for a new structure of shipboard crane designed by Maryland research group. Then a feedforward control law to greatly decrease the load sway will be introduced. This feedforward control counteracts the effect of ship rolling on load sway based on measurements of ship rolling angle at each instant. The measurement errors and also sways caused by other disturbance sources are not taken into account by this feedforward control. Next, we describe the Model Predictive Control (MPC) based nonlinear controller that is designed for this problem. The proposed controller uses an optimizer to find an open loop solution at each sampling interval for a given horizon, based on a model of the plant and an appropriately defined objective function. WC acts as a feedback control that will compensate for shortcomings of the feedforward control. Details of the controller, the design process and the simulation results are presented. C1 N Carolina Agr & Tech State Univ, Dept Elect Engn, NASA, Autonomous Control Engn Ctr, Greensboro, NC 27411 USA. RP Kimiaghalam, B (reprint author), N Carolina Agr & Tech State Univ, Dept Elect Engn, NASA, Autonomous Control Engn Ctr, Greensboro, NC 27411 USA. NR 16 TC 10 Z9 10 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 929 EP 934 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300162 ER PT S AU Starin, SR Yedavalli, RK Sparks, AG AF Starin, SR Yedavalli, RK Sparks, AG GP AACC AACC AACC TI Design of a LQR controller of reduced inputs for multiple spacecraft formation flying SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC AB Regarding multiple spacecraft formation flying, the observation is made that control thrust need only be applied coplanar to the local horizon to achieve complete controllability of a two-satellite formation. Without the need for zenith-nadir (radial) thrust, simplifications and reduction of the weight of the propulsion system may be accomplished. This work focuses an the validation of this radial-excluding control system on its own merits, and in comparison to a related system which does provide thrust parallel to the orbital radius. Simulations are performed using commercial ODE solvers to propagate the Keplerian dynamics of a controlled satellite relative to an uncontrolled, leader satellite. The conclusion is drawn that, despite the exclusion of the radial thrust axis, the remaining control thrust available still provides enough control to design a gain matrix of adequate performance using linear-quadratic regulator (LQR) techniques. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Starin, SR (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. NR 13 TC 8 Z9 8 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 1327 EP 1332 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300231 ER PT S AU Bayard, DS AF Bayard, DS GP AACC AACC AACC TI An optimization result with application to optimal spacecraft reaction wheel orientation design SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC AB This paper provides the globally optimal solution for both minimizing and maximizing the squared Frobenious norm of YQX (where X and Y are arbitrary compatibly dimensioned matrices) over the class of orthogonal matrices Q. The specialization of this optimization result to 3 dimensions is found applicable to optimally orienting spacecraft reaction wheel actuators with respect to specified torque, momentum storage, and power requirements. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bayard, DS (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 10 TC 5 Z9 7 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 1473 EP 1478 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300255 ER PT S AU Homaifar, A Shen, Y Stack, BV AF Homaifar, A Shen, Y Stack, BV GP AACC AACC AACC TI Vibration control of plate structures using PZT actuators and Type II Fuzzy Logic SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC AB This study focuses on methods for achieving active damping on plate structures by use of discrete point piezoelectric sensors and actuators structure consists of a series of thin panels that(PZTs). A typical spacecraft or launch vehicle structure consists of a series of thin panels that are clamped around their individual boundaries by a continuous metal frame. Avionic equipment mounted onto these panels can be exposed to excessive vibration due to large acoustic emanations during launch. In this study, a two degree-of-freedom model has been constructed for a structural dynamic system consisting of a linear elastic plate bonded with piezoelectric sensors and actuators. The signal from the sensors is the input of our Type H Fuzzy Logic System, and the actuators receive its output. To test this new control technique, a digital control system was built that uses the MATLAB/SIMULINK modeling software in a personal computer. The off-line simulation results confirm that the Fuzzy Type II control method is robust and efficient in the suppression of steady-state resonance vibrations. C1 N Carolina Agr & Tech State Univ, NASA, Autonomous Control Engn Ctr, Dept Elect Engn, Greensboro, NC 27411 USA. RP Homaifar, A (reprint author), N Carolina Agr & Tech State Univ, NASA, Autonomous Control Engn Ctr, Dept Elect Engn, Greensboro, NC 27411 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 1575 EP 1580 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300274 ER PT S AU Belcastro, CM Belcastro, CM AF Belcastro, CM Belcastro, CM GP AACC AACC AACC TI Application of failure detection, identification, and accommodation methods for improved aircraft safety SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE Proceedings of the American Control Conference LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC AB This paper provides an overview of technologies being developed under NASA's Aviation Safety Program to reduce aircraft accidents due to vehicle loss of control and system failures. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Belcastro, CM (reprint author), NASA, Langley Res Ctr, MS 161, Hampton, VA 23665 USA. EM christine.m.belcastro@larc.nasa.gov; celeste.m.belcastro@larc.nasa.gov NR 0 TC 4 Z9 4 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 2623 EP 2624 PG 2 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300463 ER PT S AU Soloway, D Haley, P AF Soloway, D Haley, P GP AACC AACC AACC TI Aircraft reconfiguration using Neural Generalized Predictive Control SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC AB The objective of this paper is to report the preliminary results from the research being conducted in reconfigurable flight control. This paper highlights the Neural Generalized Predictive Control algorithm which is capable of real-time control law reconfiguration, model adaptation, and the ability to identify failures in control effectiveness. This paper presents results for a fullmission six degree-of-freedom conceptual commercial transport aircraft simulation where the elevator is frozen during the flight and the algorithm reconfigures to use symmetric aileron deflections to control pitch rate, thereby stabilizing the aircraft. The neural network is activated to learn the changed dynamics of having frozen elevators and performance is improved. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Soloway, D (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 2924 EP 2929 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300517 ER PT S AU Guo, TH AF Guo, TH GP AACC AACC AACC TI A roadmap for aircraft engine life extending control SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC AB The concept of Aircraft Engine Life Extending Control is introduced. A brief description of the tradeoffs between performance and engine life are first explained. The overall goal of the life extending controller is to reduce the engine operating cost by extending the on-wing engine life while improving operational safety. The research results for NASA's Rocket Engine life extending control program are also briefly described. Major building blocks of the Engine Life Extending Control architecture are examined. These blocks include: life prediction models, engine operation models, stress and thermal analysis tools, control schemes, and intelligent control systems. The technology areas that would likely impact the successful implementation of an aircraft engine life extending control are also briefly described. Near, intermediate, and long term goals of NASA's programs are also presented. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Guo, TH (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 7 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 3702 EP 3705 PG 4 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300659 ER PT S AU Alighanbari, M Sayarrodsari, B Homaifar, A AF Alighanbari, M Sayarrodsari, B Homaifar, A GP AACC AACC AACC TI Estimation-based approach to simultaneous adaptive control and parameter estimation in filtered-LMS problems SO PROCEEDINGS OF THE 2001 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference (ACC) CY JUN 25-27, 2001 CL ARLINGTON, VA SP Amer Automat Control Council, IFAC AB This paper presents an estimation-based approach to the adaptive filtering (control) problem in the Filtered-LMS scenarios with unknown parameters in the secondary path. The approach discussed here produces a robust estimate for the unknown system parameters while fulfilling adaptive control objectives. The control objective is to limit the worst-case energy gain from exogenous disturbances, initial condition uncertainty, and parameter estimation error to the cancellation error at the output of the secondary path. Simulation results on a typical active noise cancellation problem are presented to demonstrate the main features of the proposed approach. C1 NC A&T State Univ, NASA, Autonomous Control Engn Ctr, Dept Elect Engn, Greensboro, NC 27411 USA. RP Alighanbari, M (reprint author), NC A&T State Univ, NASA, Autonomous Control Engn Ctr, Dept Elect Engn, Greensboro, NC 27411 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-6495-3 J9 P AMER CONTR CONF PY 2001 BP 4167 EP 4171 PG 5 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA BT65Z UT WOS:000173663300744 ER PT S AU Klipstein, WM Dick, GJ Jefferts, SR Walls, FL AF Klipstein, WM Dick, GJ Jefferts, SR Walls, FL GP IEEE IEEE TI Phase modulation with independent cavity-phase control in laser cooled clocks in space SO PROCEEDINGS OF THE 2001 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM & PDA EXHIBITION SE IEEE International Frequency Control Symposium LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium and PDA Exhibition CY JUN 06-08, 2001 CL SEATTLE, WA SP IEEE Ultrason Ferroelect & Frequency Control Soc, EIA Electr Components Assemblies & Mat Assoc AB The standard interrogation technique in atomic beam clocks is square-wave frequency modulation (SWFM), which suffers a first-order sensitivity to vibrations as changes in the transit time of the atoms translates to perceived frequency errors. Square-wave phase modulation (SWPM) interrogation eliminates sensitivity to this noise. We present a particular scheme utilizing independent phase control of the two cavities. The technique is being considered for use with the Primary Atomic Reference Clock in Space (PARCS), a laser-cooled cesium clock scheduled to fly aboard the International Space Station in 2005. In addition to eliminating first-order sensitivity to vibrations, the minimum attack time now in this scheme is the Rabi pulse time (t), rather than the Ramsey time (T). This helps minimize dead time and the degradation of stability due to aliasing. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Klipstein, WM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 10 TC 5 Z9 5 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-7028-7 J9 P IEEE INT FREQ CONT PY 2001 BP 25 EP 32 DI 10.1109/FREQ.2001.956155 PG 8 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Condensed Matter SC Engineering; Instruments & Instrumentation; Physics GA BU18C UT WOS:000175262100005 ER PT S AU Klipstein, WM Seidel, DJ White, JA Young, BC AF Klipstein, WM Seidel, DJ White, JA Young, BC GP IEEE IEEE TI Optical frequency standard development in support of NASA's gravity-mapping missions SO PROCEEDINGS OF THE 2001 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM & PDA EXHIBITION SE PROCEEDINGS OF THE IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium and PDA Exhibition CY JUN 06-08, 2001 CL SEATTLE, WA SP IEEE Ultrason Ferroelect & Frequency Control Soc, EIA Electr Components Assemblies & Mat Assoc ID 2-PHOTON TRANSITION; LASER; NM AB We have begun constructing all-solid-state laser systems at 778 nm and at 532 nm in support of a satellite-based gravity-mapping mission tentatively planned to fly in 2007. In each case the lasers will be stabilized at short times to high-finesse Fabry-Perot cavities similar to those of Ref. 1. At longer times the 778 nm laser will be stabilized to the 2-photon transition in rubidium [2,3]. In the 532 nm system, a frequency-doubled Nd:YAG laser with a non-planar ring oscillator (NPRO) design will be frequency-locked to a molecular iodine line [4]. We intend to combine the exquisite performance over short time scales coming from a cavity reference with the long-term stability of an atomic frequency standard with an eye towards reliability in a spaceflight application. By developing two separate candidate systems with proven performance we intend to maximize the probability of success for this mission-critical system development. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Klipstein, WM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 5 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-7028-7 J9 P IEEE INT FREQ CONT PY 2001 BP 108 EP 110 DI 10.1109/FREQ.2001.956171 PG 3 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Condensed Matter SC Engineering; Instruments & Instrumentation; Physics GA BU18C UT WOS:000175262100021 ER PT S AU Huang, SH Maleki, L Le, T AF Huang, SH Maleki, L Le, T GP IEEE IEEE TI A 10 GHz optoelectronic oscillator with continuous frequency tunability and low phase noise SO PROCEEDINGS OF THE 2001 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM & PDA EXHIBITION SE PROCEEDINGS OF THE IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium and PDA Exhibition CY JUN 06-08, 2001 CL SEATTLE, WA SP IEEE Ultrason Ferroelect & Frequency Control Soc, EIA Electr Components Assemblies & Mat Assoc AB A 10 GHz; optoelectronic oscillator (OEO) with continuous frequency tunability and low phase noise is presented. By means of coarse tuning (selecting different RF filter) and fine tuning (tuning control voltage of phase shifter), we demonstrated the OEO can operate at any frequency on X-band (similar to10 GHz, and any frequency on the interested frequency range up to at least 45 GHz) with very low phase noise. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Huang, SH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 2 TC 8 Z9 9 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-7028-7 J9 P IEEE INT FREQ CONT PY 2001 BP 720 EP 727 PG 8 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Condensed Matter SC Engineering; Instruments & Instrumentation; Physics GA BU18C UT WOS:000175262100121 ER PT S AU Thienel, J Sanner, RM AF Thienel, J Sanner, RM GP IEEE IEEE TI A coupled nonlinear spacecraft attitude controller/observer with an unknown constant gyro bias SO PROCEEDINGS OF THE 40TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-5 SE IEEE CONFERENCE ON DECISION AND CONTROL - PROCEEDINGS LA English DT Proceedings Paper CT 40th IEEE Conference on Decision and Control CY DEC 04-07, 2001 CL ORLANDO, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci AB A nonlinear control scheme for attitude control of a spacecraft is combined with a nonlinear gyro bias observer for the case of constant gyro bias. A persistency of excitation analysis shows the observer bias estimates converge to the true bias values exponentially fast. The resulting coupled, closed loop dynamics are proven by a Lyapunov analysis to be globally stable, with asymptotically perfect tracking. The analysis is extended to consider the effects of noise in addition to the gyro bias. A simulation of the proposed observer-controller design is given for a rigid spacecraft tracking a specified, time-varying attitude sequence to illustrate the theoretical claims. C1 NASA, Goddard Space Flight Ctr, Flight Dynam Anal Branch, Greenbelt, MD 20771 USA. RP Thienel, J (reprint author), NASA, Goddard Space Flight Ctr, Flight Dynam Anal Branch, Greenbelt, MD 20771 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0191-2216 BN 0-7803-7061-9 J9 IEEE DECIS CONTR P PY 2001 BP 3441 EP 3446 PG 6 WC Automation & Control Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Operations Research & Management Science SC Automation & Control Systems; Computer Science; Engineering; Operations Research & Management Science GA BV26B UT WOS:000178362200633 ER PT S AU Minor, J AF Minor, J BE Harris, RA TI Sponsor's comments - NASA SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Minor, J (reprint author), NASA, George C Marshall Space Flight Ctr, Bldg 4487,Mail Code ED03, Huntsville, AL 35812 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 5 EP 5 PG 1 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200002 ER PT S AU Ferguson, DC AF Ferguson, DC BE Harris, RA TI Spacecraft Charging - Welcome and the NASA Glenn perspective or my world and welcome to it SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB Here, we welcome participants to the 7th Spacecraft Charging Technology Conference - A Spacecraft Charging Odyssey, and lay out the NASA Glenn Research Center perspective on spacecraft charging past, present, and future. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Ferguson, DC (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 83 EP 88 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200013 ER PT S AU Carruth, MR Schneider, T McCollum, M Finckenor, M Suggs, R Ferguson, D Katz, I Mikatarian, R Alred, J Pankop, C AF Carruth, MR Schneider, T McCollum, M Finckenor, M Suggs, R Ferguson, D Katz, I Mikatarian, R Alred, J Pankop, C BE Harris, RA TI ISS and space environment interactions in event of plasma contactor failure SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB Solar arrays on the International Space Station (ISS) operate at 160 volts. The negative side of the power system is grounded to ISS structure. The high voltage solar arrays coupled with ISS design and materials properties can lead to detrimental interactions with the ionospheric plasma. A plasma contactor unit (PCU) on ISS provides a "ground wire" to control the voltage between the ISS structure and local plasma and prevents such interactions. An evaluation of possible effects that could result in the event of plasma contactor failure was undertaken and is reported in this paper. In general, any identified impacts on ISS function take several months of contactor malfunction to develop. Possible hazards to crewmembers on EVA are addressed and sufficient controls have been put in place. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Carruth, MR (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 95 EP 100 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200015 ER PT S AU Frederickson, AR Benson, CE AF Frederickson, AR Benson, CE BE Harris, RA TI Improved testing procedures for spacecraft discharge pulses SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB A new set of discharge laws has been developed, if only qualitatively in some ways, which guides one to better develop testing procedures for spacecraft pulse discharge testing. Other papers indicate how the discharge is generated by a burst of gas. The physics of that gas discharge provides a set of discharge phenomena that must be considered when designing ground tests for insulator discharges for spacecraft systems. Most important, the amplitude of the discharge pulse is critically dependent on: the distribution of image charges prior to the discharge, the path of current through the gas discharge, the amount of gas issued in the event, and the electric field in the vacuum that drives the gas current avalanche. The amount of gas issued into the vacuum is critically dependent on the electric field inside the insulator. Thus, proper testing must simulate the electric field and image charge distributions that actually occur on structures in space. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Frederickson, AR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 109 EP 114 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200017 ER PT S AU Minor, J AF Minor, J BE Harris, RA TI NASA's Space Environments and Effects (SEE) program SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB The return of the Long Duration Exposure Facility (LDEF) in 1990 brought a wealth of space exposure data on materials, paints, solar cells, adhesives and other data on the many space environments. The effects of the harsh space environments can provide damaging or even disabling effects on a spacecraft, its sub-systems, materials and instruments. In partnership with industry, academia, and other US and international government agencies, the National Aeronautics & Space Administration's (NASA's) Space Environments & Effects (SEE) Program defines the space environments and provides technology development to accommodate or mitigate these harmful environments on the spacecraft. This program (agency-wide in scope but managed at the Marshall Space Flight Center) provides a very comprehensive and focused approach to understanding the space environment. It does this by defining the best techniques for both flight- and ground-based experimentation, updating models which predict both the environments and the environmental effects on spacecraft and ensuring that this information is properly maintained and inserted into spacecraft design programs. This paper will describe the current SEE Program and discuss several current technology development activities associated with the spacecraft charging phenomenon. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Minor, J (reprint author), NASA, George C Marshall Space Flight Ctr, Bldg 4487,Mail Code ED03, Huntsville, AL 35812 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 223 EP 228 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200035 ER PT S AU Frederickson, AR Whittlesey, AC Garrett, HB AF Frederickson, AR Whittlesey, AC Garrett, HB BE Harris, RA TI Comparing CRRES internal discharge monitor results with ground tests and published guidelines SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY ID SPACECRAFT; ENVIRONMENT; INSULATORS; SCATHA AB Various attempts have been made to reconcile data from the CRRES IDM space experiment, and other space experiments with ground test results, with modeling and with guidelines. Based on recent ground testing supported by the NASA/MSFC SEE program and other NASA programs, it is now easier to compare the in-space data with ground test data. Recent test data will be described to show how these results improve our understanding. Suggestions are offered for improving existing guidelines, focusing on NASA-HDBK-4002 and NASA TP-2361. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Frederickson, AR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 303-217, Pasadena, CA 91109 USA. NR 20 TC 1 Z9 1 U1 0 U2 2 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 265 EP 274 PG 10 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200042 ER PT S AU Ferguson, DC Hillard, GB Morton, TL AF Ferguson, DC Hillard, GB Morton, TL BE Harris, RA TI The Floating Potential Probe (FPP) for ISS - Operations and initial results SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB In this paper we report early results from the Floating Potential Probe (FPP) recently installed on the International Space Station (ISS). The data show that FPP properly measures the electrical potential of ISS structure with respect to the plasma it is flying through. FPP Langmuir probe data seem to give accurate measurements of the ambient plasma density, and are Generally consistent with the IRI-90 model. FPP data are used to judge the performance of the ISS Plasma Contacting Units (PCUs), and to evaluate the extent of ISS charging in the absence of the PCUs.. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Ferguson, DC (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 12 TC 0 Z9 0 U1 1 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 365 EP 370 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200059 ER PT S AU Vaughn, JA Schneider, TA Finckenor, MM AF Vaughn, JA Schneider, TA Finckenor, MM BE Harris, RA TI Life testing of the hollow cathode plasma contactor for the ProSEDS mission SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB The Propulsive Small Expendable Deployer System (ProSEDS) mission is designed to provide an on-orbit demonstration of the electrodynamic propulsion capabilities of tethers in space. The ProSEDS experiment will be a secondary payload on a Delta II unmanned expendable booster. A 5-km conductive tether is attached to the Delta II second stage and collects current from the low Earth orbit (LEO) plasma. A hollow cathode plasma contactor (HCPC) emits the collected electrons from the Delta II, completing the electrical circuit with the ambient plasma. The current flowing through the tether generates thrust based on the Lorentz Force Law. The thrust will be generated opposite to the velocity vector, slowing down the spacecraft and causing it to de-orbit in approximately 14 days compared to the normal 6 months. A 10-km non-conductive tether is between the conductive tether and an endmass containing several scientific instruments. Extensive testing of a development unit for the HCPC has been performed at the Marshall Space Flight Center. The purpose to the testing was to examine the HCPC design and ensure that the design would meet the unique requirements of the ProSEDS mission. Because of the science requirements to measure the background ambient plasma, the HCPC must operate on a duty cycle, where the HCPC is shutdown once every minute while on orbit. Because of this unique requirement, the development unit for tested for a simulated ProSEDS mission where the HCPC was cycled on and off for 10,095 cycles. RP Vaughn, JA (reprint author), NASA, George C Marshall Space Flight Ctr, ED31, Huntsville, AL 35812 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 371 EP 376 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200060 ER PT S AU Schneider, TA Carruth, MR Finckenor, MM Vaughn, JA Heard, J Ferguson, D AF Schneider, TA Carruth, MR Finckenor, MM Vaughn, JA Heard, J Ferguson, D BE Harris, RA TI An experimental investigation of the effects of charging on the international space station SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB An experimental investigation has been undertaken to determine the effects associated with operating the International Space Station (ISS) without a Plasma Contactor Unit (PCU). The role of the PCU is to maintain the potential of the ISS to within 40 volts of the ambient plasma potential. In the event of a PCU failure, ISS structure may charge to -160 volts with respect to the Low Earth Orbit (LEO) plasma, due to the use of high voltage photovoltaic solar arrays. Operation without a PCU will result in the charging of the oxide layers on anodized aluminum components facing into the RAM direction. In this investigation, arcs were observed as a result of anodized materials charging in a plasma environment. Actual ISS materials were used in the investigation. The materials included meteoroid and debris shield samples, as well as components from the Extra-vehicular Mobility Unit (EMU). Results show that the occurrence of arcs was dependent on several factors including material composition and applied voltage. Damage resulting from an arc is shown, as well as the effect of arc damage on thermal properties. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Schneider, TA (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 405 EP 410 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200066 ER PT S AU Frederickson, AR AF Frederickson, AR BE Harris, RA TI New scaling laws for spacecraft discharge pulses SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB The electrostatic discharge pulse waveform, current as a function of time, was investigated as many parameters were varied. Electron beams from 5 keV to 1.5 MeV and beam current densities from I pA/cm(2) to 2 nA/cm(2) were used to charge insulating samples. FR4 circuit boards, electrical connectors, Duroid boards, space-rated Teflon-insulated wiring, Kapton wiring, and epoxy fiberglass were irradiated, and the resulting pulses were recorded. The old scaling laws were found to result from the condition of very high static electric field inside the insulator, fields beyond those expected in space service. At realistic internal static field strength, the pulse amplitude is much less than that predicted by the old scaling, laws. For reasonable fields, the pulses do not clearly scale with sample area, and instead, become constant at areas larger than a few square centimeters. Additionally, the "geometry" of the electric field in the vacuum also controls the pulse amplitude. A scaling law for pulse event rate now appears obtainable. A scaling law for the voltage and energy imparted to any load resistance is now available. Pulse rate and amplitude both increase with increasing internal electric field. Usually, small electrodes receive only a small part of the pulsed current, but under some conditions all of the discharge current will go to a small electrode. A new conceptual framework has evolved such that it may now be possible to measure the static field strength and radiation-charging rate inside the insulator material by measuring the pulse rate. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Frederickson, AR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 417 EP 422 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200068 ER PT S AU Frederickson, AR Benson, CE AF Frederickson, AR Benson, CE BE Harris, RA TI Gas discharge phenomena in spacecraft discharge pulses SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Frederickson, AR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 467 EP 467 PG 1 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200076 ER PT S AU Vayner, B Galofaro, J Ferguson, D AF Vayner, B Galofaro, J Ferguson, D BE Harris, RA TI Arc inception mechanism on a solar array immersed in a low-density plasma SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY ID SURFACE FLASHOVER; VOLTAGE; DISCHARGES; VACUUM AB In this report, results are presented of an experimental and theoretical study of arc phenomena and snapover for two samples of solar arrays immersed in argon plasma. The effects of arcing, and snapover are investigated. IN curves are measured, and arc and snapover inception voltages and are rates are determined within the wide range of plasma parameters. A considerable increase in arc rate due to absorption of molecules from atmospheric air has been confirmed. It is shown that increasing gas pressure causes increasing ion current collection and, consequently, arc rate even though the effect of conditioning also takes place. Arc sites have been determined by employing a video-camera. It is confirmed that keeping sample under high vacuum for a long time results in shifting arc threshold voltage well below -300 V. The results obtained seem to be important for the understanding of arc inception mechanism. C1 NASA, Glenn Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. RP Vayner, B (reprint author), NASA, Glenn Res Ctr, Ohio Aerosp Inst, MS 302-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 469 EP 474 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200077 ER PT S AU Hillard, GB Ferguson, DC Snyder, DB AF Hillard, GB Ferguson, DC Snyder, DB BE Harris, RA TI Design and testing of the Floating Potential Probe for ISS SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB Flight 4A was an especially critical mission for the International Space Station (ISS). For the first time, the high voltage solar arrays generated significant amounts of power and long predicted environmental interactions (high negative floating potential and concomitant dielectric charging) became serious concerns. Furthermore, the same flight saw the Plasma Contacting Unit (PCU) deployed and put into operation to mitigate and control these effects. The ISS program office has recognized the critical need to verify, by direct measurement, that ISS does not charge to unacceptable levels. A Floating Potential Probe (FPP) was therefore deployed on ISS to measure ISS floating potential relative to the surrounding plasma and to measure relevant plasma parameters. The primary objective of FPP is to verify that ISS floating potential does not exceed the specified level of 40 volts with respect to the ambient. Since it is expected that in normal operations the PCU will maintain ISS within this specification, it is equivalent to say that the objective of FPP is to monitor the functionality of the PCU. In this paper, we present a top-level overview of the design and testing of the ISS FPP. In a separate paper, the operations and results obtained so far by the FPP will be presented. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Hillard, GB (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 485 EP 490 PG 6 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200080 ER PT S AU Garrett, HB Evans, RW AF Garrett, HB Evans, RW BE Harris, RA TI Internal electrostatic discharge environment at Jupiter SO PROCEEDINGS OF THE 7TH SPACECRAFT CHARGING TECHNOLOGY CONFERENCE: 2001: A SPACECRAFT CHARGING ODYSSEY SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 7th Spacecraft Charging Technology Conference CY APR 23-27, 2001 CL EUROPEAN SPACE AGCY, NOORDWIJK, NETHERLANDS SP AFRL, CNES, DERK, NASA HO EUROPEAN SPACE AGCY AB Although a fairly common occurrence in the Earth's environment, internal electrostatic discharge (or IESD) is seldom discussed with regards to extraterrestrial space missions. The Voyager 1 flyby of Jupiter, however, clearly demonstrated the importance of this phenomena in the context of the jovian radiation belts-Voyager suffered 42 Power-On Resets that were ultimately attributed to IESD during passage through the jovian belts. As several missions are being considered for the jovian environment, it is appropriate to revisit the effects observed on Voyager and review what we now know of the jovian IESD environment. In particular, NASA is considering a mission to orbit the moon Europa for the purpose of a close-up look at this possibly oceanic moon to determine if it might harbor life. This presentation will review the previous IESD observations from Voyager 1 in the context of our new understanding of the jovian radiation belts based on Galileo data and present simple tools for estimating IESD at Jupiter. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Garrett, HB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 23 TC 2 Z9 2 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-745-3 J9 ESA SP PUBL PY 2001 VL 476 BP 609 EP 615 PG 7 WC Engineering, Aerospace SC Engineering GA BU07A UT WOS:000174908200100 ER PT B AU Handschuh, RF AF Handschuh, RF BE Qin, DT Chen, XO Chen, BK Lin, C TI Testing of face-milled spiral bevel gears at high-speed and load SO PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MECHANICAL TRANSMISSIONS LA English DT Proceedings Paper CT International Conference on Mechanical Transmissions (ICMT 2001) CY APR 05-09, 2001 CL CHONGQING, PEOPLES R CHINA DE gears; transmissions AB Spiral bevel gears are an important drive system components of rotorcraft (helicopters) currently in use. In this application the spiral bevel gears are required to transmit very high torque at high rotational speed. Available experimental data on the operational characteristics for thermal and structural behavior is relatively small in comparison to that found for parallel axis gears. An ongoing test program has been in place at NASA Glenn Research Center over the last ten years to investigate their operational behavior at operating conditions found in aerospace applications. This paper will summarize the results of the tests conducted on face-milled spiral bevel gears. The data from the pinion member (temperature and stress) were taken at conditions from slow-roll to 14400 rpm and up to 537 kW (720 hp). The results have shown that operating temperature is affected by the location of the lubricating jet with respect to the point it is injected and the operating conditions that are imposed. Also the stress measured from slow-roll to very high rotational speed, at various torque levels, indicated little dynamic affect over the rotational speeds tested. C1 NASA, Glenn Res Ctr, US Army Res Lab, Vehicle Technol Ctr, Washington, DC 20546 USA. RP Handschuh, RF (reprint author), NASA, Glenn Res Ctr, US Army Res Lab, Vehicle Technol Ctr, Washington, DC 20546 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU CHINA MACHINE PRESS PI BEIJING PA NO 1 NANLI BAIWANZHUANG, BEIJING, PEOPLES R CHINA BN 7-900066-14-4 PY 2001 BP 83 EP 89 PG 7 WC Engineering, Mechanical SC Engineering GA BS37T UT WOS:000169681100015 ER PT S AU Jenniskens, P AF Jenniskens, P BE Warmbein, B TI Forecast for the remainder of the Leonid storm season. (ESA SP-495) SO PROCEEDINGS OF THE METEOROIDS 2001 CONFERENCE SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT Meteoroids 2001 Conference CY AUG 06-10, 2001 CL SWEDISH INST SPACE PHYS, KIURNA, SWEDEN SP European Space Agcy, European Off Aerosp Res & Dev, USAF Off Sci Res, USAF Res Lab, Swedish Space Corp, Municipal Kiruna, Umea Univ, Dept Space Phys, Lulea Univ Technol, Wenner Gren Fdn, Langman Entrepreneurial Fdn, County Adm Board Norrbotten, Swedish Res Council HO SWEDISH INST SPACE PHYS ID DUST TRAIL; COMET 55P/TEMPEL-TUTTLE; NUCLEUS AB The dust trails of comet 55P/Tempel-Tuttle lead to Leonid storms on Earth, threatening satellites in orbit. Here we derive a model that accounts in detail for the observed properties of the dust trails evolved by the comet at previous oppositions. The model is interpreted as a projection of the comet light curve and the effects of a precessing comet nucleus. We find that the directional ejection of dust by a northerly jet causes the 1767-dust trail to be closer to Earth's orbit in 2001 than originally thought; increasing expected peak Leonid rates to a significant storm for North American observers. Predictions for the 2002 storms are less affected. C1 NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. RP Jenniskens, P (reprint author), NASA, Ames Res Ctr, SETI Inst, Mail Stop 239-4, Moffett Field, CA 94035 USA. NR 39 TC 4 Z9 4 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-805-0 J9 ESA SP PUBL PY 2001 VL 495 BP 83 EP 90 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT99B UT WOS:000174658200014 ER PT S AU Jenniskens, P AF Jenniskens, P BE Warmbein, B TI Meteors as a delivery vehicle for organic matter to the early earth (ESA SP-495) SO PROCEEDINGS OF THE METEOROIDS 2001 CONFERENCE SE ESA Special Publications LA English DT Proceedings Paper CT Meteoroids 2001 Conference CY AUG 06-10, 2001 CL SWEDISH INST SPACE PHYS, KIURNA, SWEDEN SP European Space Agcy, European Off Aerosp Res & Dev, USAF Off Sci Res, USAF Res Lab, Swedish Space Corp, Municipal Kiruna, Umea Univ, Dept Space Phys, Lulea Univ Technol, Wenner Gren Fdn, Langman Entrepreneurial Fdn, County Adm Board Norrbotten, Swedish Res Council HO SWEDISH INST SPACE PHYS ID INTERPLANETARY DUST PARTICLES; LEONID METEORS; WATER; ASTEROIDS; NITROGEN; CARBON AB Only in recent years has a concerted effort been made to study the circumstances under which extraterrestrial organic matter is accreted on Earth by way of meteors. Meteors are the luminous phenomena associated with the (partial) ablation of meteoric matter and represent the dominant pathway from space to Earth, with the possible exception of rare giant impacts of asteroids and comets. Meteors dominated the supply of organics to the early Earth if organic matter survived this pathway efficiently. Moreover, meteors are a source of kinetic energy that can convert inert atmospheric gasses such as CO2, N-2 and H2O into useful compounds, such as HCN and NO. Understanding these processes relies heavily on empirical evidence that is still very limited. Here I report on the observations in hand and discuss their relevance in the context of the origin of life. C1 NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. RP Jenniskens, P (reprint author), NASA, Ames Res Ctr, SETI Inst, Mail Stop 239-4, Moffett Field, CA 94035 USA. EM pjenniskens@mail.arc.nasa.gov NR 34 TC 14 Z9 14 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-805-0 J9 ESA SPEC PUBL PY 2001 VL 495 BP 247 EP 254 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT99B UT WOS:000174658200041 ER PT B AU Gilliam, DP Kelly, JC Powell, JD Bishop, M AF Gilliam, DP Kelly, JC Powell, JD Bishop, M GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Development of a software security assessment instrument to reduce software security risk SO PROCEEDINGS OF THE TENTH IEEE INTERNATIONAL WORKSHOPS ON ENABLING TECHNOLOGIES: INFRASTRUCTURE FOR COLLABORATIVE ENTERPRISES LA English DT Proceedings Paper CT 10th IEEE International Workshop on Enabling Technologies: Infrastructure for Collaborative Enterprises (WET ICE 2001 ) CY JUN 20-22, 2001 CL MIT, CAMBRIDGE, MA SP IEEE Comp Soc, IEEE Comp Soc Tech Comm Data Engn, Concurrent Engn Res Ctr, Natl Inst Stand & Technol, Linkoping Univ HO MIT DE security toolset; vulnerability matrix; property-based testing; model checking; security verification AB This paper discusses joint work by the California Institute of Technology's Jet Propulsion Laboratory and the University of California at Davis (UC Davis) sponsored by the National Aeronautics and Space Administration to develop a security assessment instrument for the software development and maintenance life cycle. The assessment instrument is a collection of tools and procedures to support development of secure software. Specifically, the instrument offers a formal approach for engineering network security into software systems and application throughout the software development arid maintenance life cycle. The security assessment instrument includes a Vulnerability Matrix (VMatrix) with platform/ application, and signature fields in a database. The information in the VMatrix has become the bases for the Database of Vulnerabilities, Exploits, and Signatures (DOVES) at UC Davis. The instrument also includes a set of Security Assessment Tools (SAT), including the development of a property-based testing tool by UC Davis, to slice software code looking for specific vulnerability properties. A third component of the research is an investigation into the verification of software designs for compliance to security properties. This is based on innovative model checking approaches that will facilitate the development and verification of software security models. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. EM david.p.Gilliam@jpl.nasa.gov; john.c.kellyw@jpl.nasa.gov; John.Powell@jpl.nasa.gov; bishop@cs.ucdavis.edu NR 8 TC 2 Z9 2 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1269-0 PY 2001 BP 144 EP 149 DI 10.1109/ENABL.2001.953404 PG 6 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BT36S UT WOS:000172786100027 ER PT S AU Johnson, NL AF Johnson, NL BE SawayaLacoste, H TI Activities on space debris in US SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB In the U.S. space debris activities are addressed at all government levels, from the Executive Office of the President to the individual federal agencies to specialized centers, laboratories, organizations, and research groups. U.S. Space Policy specifically challenges government agencies to seek to minimize the creation of space debris and to promote debris minimization practices, both domestically and internationally. A set of space debris mitigation standard practices has been developed and adopted by relevant U.S. government agencies, and their application by the commercial aerospace community is highly encouraged. A growing number of U.S. government agencies have issued their own space debris mitigation policies, directives, regulations, and standards. Space debris research, including the definition and modeling of the current and future near-Earth space environment and the development of debris protection technologies, is principally conducted by NASA and the Department of Defense. The U.S. Space Surveillance Network continues to provide the most complete and timely characterization of the population of space debris larger than 10 cm. During the past several years major advancements have been achieved in extending this environment definition in LEO to include particles as small as only a few millimeters. The inspection of returned spacecraft surfaces continues to shed light on the even smaller debris population. With improvements in computer technology, new and more capable programs have been and are being developed to solve a number of operational and research problems. Finally, the academic and industrial sectors of the U.S. are also increasing their participation in and contributions to space debris operations and research. The cooperation of spacecraft and launch vehicle developers and operators is essential to the U.S. objective of promoting the preservation of the space environment for future generations. C1 NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Office, Houston, TX 77058 USA. RP Johnson, NL (reprint author), NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Office, SN3, Houston, TX 77058 USA. NR 7 TC 2 Z9 2 U1 0 U2 3 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 13 EP 19 PG 7 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200001 ER PT S AU Stansbery, G AF Stansbery, G BE SawayaLacoste, H TI Preliminary results from the US participation in the 2000 Beam Park Experiment SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB The United States participated in the 2000 Beam Park Experiment (BPE) conducted in late October, 2000 under the auspices of the Inter-Agency Space Debris Coordination Committee (IADC). The U.S. participated using several sensors which have participated in previous campaigns: Haystack, TRADEX, and COBRA DANE radars, and the Liquid Mirror Telescope. New to the BPE experiments this time are the GBR-P radar located at Kwajalein Atoll and the Haystack Auxiliary (HAX) radar located in Massachusetts. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Stansbery, G (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 49 EP 52 PG 4 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200006 ER PT S AU Johnson, NL AF Johnson, NL BE SawayaLacoste, H TI Space debris modeling at NASA SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB Since the Second European Conference on Space Debris in 1997, the Orbital Debris Program Office at the NASA Johnson Space Center has undertaken a major effort to update and improve the principal software tools employed to model the space debris environment and to evaluate mission risks. NASA's orbital debris engineering model, ORDEM, represents the current and near-term Earth orbital debris population from the largest spacecraft to the smallest debris in a manner which permits spacecraft engineers and experimenters to estimate the frequency and velocity with which a satellite may be struck by debris of different sizes. Using expanded databases and a new program design, ORDEM2000 provides a more accurate environment definition combined with a much broader array of output products in comparison with its predecessor, ORDEM96. Studies of the potential long-term space debris environment are now conducted with EVOVLE 4.0, which incorporates significant advances in debris characterization and breakup modeling. An adjunct to EVOLVE 4.0, GEO-EVOLVE has been created to examine debris issues near the geosynchronous orbital regime. In support of NASA Safety Standard (NSS) 1740.14, which establishes debris mitigation guidelines for all NASA space programs, a set of evaluation tools called the Debris Assessment Software (DAS) is specifically designed for program offices to determine whether they are in compliance with NASA debris mitigation guidelines. DAS 1.5 has recently been completed with improved WINDOWS compatibility and graphics functions. DAS 2.0 will incorporate guideline changes in a forthcoming revision to NSS 1740.14. Whereas DAS contains a simplified model to calculate possible risks associated with satellite reentries, NASA's higher fidelity Object Reentry Survival Analysis Tool (ORSAT) has been upgraded to Version 5.0. With the growing awareness of the potential risks posed by uncontrolled satellite reentries to people and property on Earth, the application of both DAS and ORSAT has increased markedly in the past two years. C1 NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Off, Houston, TX 77058 USA. RP Johnson, NL (reprint author), NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Off, SN3, Houston, TX 77058 USA. NR 18 TC 0 Z9 0 U1 1 U2 5 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 259 EP 264 PG 6 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200042 ER PT S AU Johnson, NL AF Johnson, NL BE SawayaLacoste, H TI Evidence for historical satellite fragmentations in and near the geosynchronous regime SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB Satellite fragmentations are well known to be the principal source of debris larger than 1 cm in low Earth orbit (LEO). Since 1963, over 500 missions have placed more than 830 spacecraft and upper stages in or near the geosynchronous (GEO) regime. If the historical non-GEO breakup rate for other than deliberate or aerodynamic causes is applied to GEO, then as many as 15 breakups might be expected near GEO. Some space surveillance specialists have interpreted specific GEO satellite orbital perturbations as evidence for collisions or explosions for up to two dozen GEO satellites. Moreover, recent searches for small (20-100 cm diameter) objects near GEO have been undertaken in the US and Europe, and preliminary results suggest a significant small debris population. However, to date only two GEO regime breakups have been identified with confidence. This paper summarizes a study of potential indicators of GEO satellite breakups and a review of the two known GEO breakups and of satellites which have been the subject of breakup speculation. Recent GEO debris observations have not revealed obvious breakup clouds which would support these hypotheses. Although some of the detected debris may be of breakup origin, some debris might well have originated from non-fragmentation sources. A LEO non-fragmentation analog might explain some of the observed orbital perturbations in GEO. C1 NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Off, Houston, TX 77058 USA. RP Johnson, NL (reprint author), NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Off, SN3, Houston, TX 77058 USA. NR 9 TC 6 Z9 6 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 355 EP 359 PG 5 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200057 ER PT S AU Jorgensen, K Culp, RD Clark, RN AF Jorgensen, K Culp, RD Clark, RN BE SawayaLacoste, H TI Spectral measurements of returned spacecraft surfaces and the implications for space debris material measurements SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB Knowledge of the physical properties of orbital debris is necessary for modeling the debris environment. Current methods determine the size and mass of orbital debris based on knowledge or assumption of the material type of the piece. By using spectroscopy, one can determine the material type of the piece by comparing the absorption features of its spectra to that of lab spectra for given materials. The goal of this research is not to improve the models themselves, but to improve the information others use to make the models. In order to determine the effects of the space environment on the reflectance spectra of spacecraft materials, researchers measured materials from returned spacecraft. Measurements of material degradation for returned missions from the Long Duration Exposure Facility (LDEF) are documented herein. When the spectra of returned spacecraft materials were compared with the pre-flight laboratory spectra degradation in the samples were seen mostly in the visible wavelengths, while the samples showed similar features in the near-infrared. Overall, the results displayed less degradation on the spaceflight samples than anticipated. The spectral measurements of returned spacecraft materials lent credence to continuing the study of determining the material type of orbital debris using spectroscopy. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Jorgensen, K (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 385 EP 389 PG 5 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200062 ER PT S AU Hall, DT Anz-Meador, P AF Hall, DT Anz-Meador, P BE SawayaLacoste, H TI A solar-flux temperature relationship derived from multiple-satellite orbital decay SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB We report an analysis of the orbital decay rates of 95 satellites to determine the best-fit relationship between solar 10.7cm flux (F-10.7cm) and Earth's globally-averaged exospheric temperature (Tinfinity). The analysis focuses on reproducing atmospheric drag rates observed over a period spanning nearly 3 solar cycles, and yields globally-averaged exospheric temperatures appropriate for use in models that project Earth's satellite and orbital debris populations many decades into the future. Exospheric temperatures derived using an oblate-Earth/rotating atmosphere drag model are uniformly larger than best-fit temperatures derived using a spherical-Earth/non-rotating atmosphere model, an effect that should be included in long-term orbital debris projection models. C1 NASA, Lyndon B Johnson Space Ctr, Hernandez Engn Inc, Houston, TX 77058 USA. RP Hall, DT (reprint author), NASA, Lyndon B Johnson Space Ctr, Hernandez Engn Inc, 2400 NASA Rd 1,Mail Code C-104, Houston, TX 77058 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 411 EP 414 PG 4 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200067 ER PT S AU Theall, J Liou, JC Matney, M Kessler, D AF Theall, J Liou, JC Matney, M Kessler, D BE SawayaLacoste, H TI The space debris environment for the ISS orbit SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana ID INTERPLANETARY AB Recent work at the Johnson Space Center has focused on updating the existing space debris models. The Orbital Debris Engineering Model (ORDEM) has been restructured to take advantage of state-of-the-art desktop computing capability and revised with recent measurements from Haystack, HAX, and Goldstone radars, additional analysis of LDEF and Space Shuttle impacts, and the most recent Space Surveillance Network catalog. The new model also contains the capability to extrapolate the current environment in time to the year 2030. A revised meteoroid model that includes the meteor showers for Earth orbit has also been developed. This paper quantifies the space debris environment for the ISS orbit from anthropogenic and natural sources. Particle flux and velocity distributions as functions of size and angle are given for particles 10 microns and larger. The environment is projected forward in time until 2030. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Theall, J (reprint author), NASA, Lyndon B Johnson Space Ctr, Mailcode SN3, Houston, TX 77058 USA. NR 11 TC 0 Z9 0 U1 0 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 429 EP 432 PG 4 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200070 ER PT S AU Ahmed, M Mangus, D Burch, P AF Ahmed, M Mangus, D Burch, P BE SawayaLacoste, H TI Risk management approach for de-orbiting of the Compton Gamma Ray Observatory SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB De-orbiting of space debris into Earth is one of the methods to control and minimize the degradation of the space environment. The de-orbiting scenario poses a challenge of providing safety for the Earth population and other space-based assets below the orbit track of the spacecraft being de-orbited. Rigorous risk management is needed to provide the necessary safety margin for de-orbit operations. These challenges were faced during the controlled de-orbit of the Compton Gamma Ray Observatory (CGRO) into the Pacific Ocean on June 4, 2000. This paper presents a risk management approach utilized at various stages of this mission; processes used to identify credible contingencies; and planned responses to contingencies for use during mission execution. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ahmed, M (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 495 EP 500 PG 6 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200081 ER PT S AU Bacon, J AF Bacon, J BE SawayaLacoste, H TI International space station as an observation platform for hypersonic re-entry of its visiting vehicles SO PROCEEDINGS OF THE THIRD EUROPEAN CONFERENCE ON SPACE DEBRIS, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 3rd European Conference on Space Debris CY MAR 19-21, 2001 CL DARMSTADT, GERMANY SP European Space Agcy, Agenzia Spaziale Italiana AB The International Space Station (ISS) will receive an armada of visiting supply vehicles during its life in orbit. Over 500 tons of material will be destroyed in targeted re-entries of these vehicles. Because all such re-entries lie in the same orbital plane of the station, and because the visiting vehicles typically deorbit within a few hours of departure, the ISS will usually be within sight of the re-entry process, at a range of only 300-600 kilometers. This vantage point offers an unprecedented opportunity for systematically measuring hypersonic destructive processes. This paper examines the integrated operational constraints of the ISS, its supply vehicles, and candidate sensors which can be employed in the scientific observation of the re-entry process. It is asserted the ISS program has the potential to reduce the worldwide risks from future deorbiting spacecraft, through systematic experimental characterization of the factors which affect the rupture, debris survival, and footprint size of its visiting vehicle fleet. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Bacon, J (reprint author), NASA, Lyndon B Johnson Space Ctr, OM5, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-733-X J9 ESA SP PUBL PY 2001 VL 473 BP 547 EP 551 PG 5 WC Engineering, Aerospace; Engineering, Environmental SC Engineering GA BU06Z UT WOS:000174907200089 ER PT B AU Boyan, J Mitzenmacher, M AF Boyan, J Mitzenmacher, M GP SIAM SIAM SIAM TI Improved results for route planning in stochastic transportation networks SO PROCEEDINGS OF THE TWELFTH ANNUAL ACM-SIAM SYMPOSIUM ON DISCRETE ALGORITHMS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT 12th Annual ACM-SIAM Symposium on Discrete Algorithms CY JAN 07-09, 2001 CL WASHINGTON, DC SP ACM SIGACT, SIAM Act Grp Discrete Math AB In the bus network problem, the goal is to generate a plan for getting from point X to point Y within a city using buses in the smallest expected time. Because bus arrival times are not determined by a fixed schedule but instead may be random, the problem requires more than standard shortest path techniques. In recent work, Datar and Ranade provide algorithms in the case where bus arrivals are assumed to be independent and exponentially distributed. We offer solutions to two important generalizations of the problem, answering open questions posed by Datar and Ranade. First, we provide a polynomial time algorithm for a much wider class of arrival distributions, namely those with increasing failure rate. This class includes not only exponential distributions but also uniform, normal, and gamma distributions. Second, in the case where bus arrival times are independent, and geometric discrete random variables, we provide an algorithm for transportation networks of buses and trains, where trains run according to a fixed schedule. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Boyan, J (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 9 TC 9 Z9 9 U1 0 U2 1 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-490-7 J9 SIAM PROC S PY 2001 BP 895 EP 902 PG 8 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BU87L UT WOS:000177257800123 ER PT J AU Shyy, W Papila, N Vaidyanathan, R Tucker, K AF Shyy, W Papila, N Vaidyanathan, R Tucker, K TI Global design optimization for aerodynamics and rocket propulsion components SO PROGRESS IN AEROSPACE SCIENCES LA English DT Review ID SENSITIVITY ANALYSIS; SHAPE OPTIMIZATION; NEURAL-NETWORKS; DYNAMICS; EQUATION AB Modern computational and experimental tools for aerodynamics and propulsion applications have matured to a stage where they can provide substantial insight into engineering processes involving fluid flows, and can be Fruitfully utilized to help improve the design of practical devices. In particular. rapid and continuous development in aerospace engineering demands that new design concepts be regularly proposed to meet goals for increased performance, robustness and safety while concurrently decreasing cost. To date, the majority of the effort in design optimization of fluid dynamics has relied on gradient-based search algorithms. Global optimization methods can utilize the information collected from various sources and by different tools. These methods offer multi-criterion optimization, handle the existence of multiple design points and trade-offs via insight into the entire design space, can easily perform tasks in parallel, and are often effective in filtering the noise intrinsic to numerical and experimental data. However, a successful application of the global optimization method needs to address issues related to data requirements with an increase in the number of design variables, and methods for predicting the model performance. In this article, we review recent progress made in establishing suitable global optimization techniques employing neural-network- and polynomial-based response surface methodologies. Issues addressed include techniques for construction of the response surface, design of experiment techniques for supplying information in an economical manner, optimization procedures and multi-level techniques, and assessment of relative performance between polynomials and neural networks. Examples drawn From wing aerodynamics, turbulent diffuser flows, gas-gas injectors, and supersonic turbines are employed to help demonstrate the issues involved in an engineering design context. Both the usefulness of the existing knowledge to aid current design practices and the need for future research are identified. (C) 2001 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Florida, Dept Aerosp Engn Mech & Engn Sci, Gainesville, FL 32611 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Shyy, W (reprint author), Univ Florida, Dept Aerosp Engn Mech & Engn Sci, 231 Aerosp Bldg, Gainesville, FL 32611 USA. EM wei-shyy@ufl.edu OI Shyy, Wei/0000-0001-6670-5394 NR 62 TC 82 Z9 89 U1 2 U2 20 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0376-0421 J9 PROG AEROSP SCI JI Prog. Aeosp. Sci. PD JAN PY 2001 VL 37 IS 1 BP 59 EP 118 DI 10.1016/S0376-0421(01)00002-1 PG 60 WC Engineering, Aerospace SC Engineering GA 415YR UT WOS:000167751600003 ER PT J AU Leonard, CL Bidigare, RR Seki, MP Polovina, JJ AF Leonard, CL Bidigare, RR Seki, MP Polovina, JJ TI Interannual mesoscale physical and biological variability in the North Pacific Central Gyre SO PROGRESS IN OCEANOGRAPHY LA English DT Article; Proceedings Paper CT Conference on Beyond El Nino CY MAR, 2000 CL LA JOLLA, CA ID TEMPORAL VARIABILITY; SATELLITE ALTIMETRY; COMMUNITY STRUCTURE; EQUATORIAL PACIFIC; EL-NINO; OCEAN; PHYTOPLANKTON; CHLOROPHYLL; DISTRIBUTIONS AB Springtime composites of surface chlorophyll a (chi) from the SeaWiFS instrument show a sharp increase in chi standing stock (from similar to0.1 to 0.3 mg m(-3)) occurring between 30 degrees and 40 degreesN in the eastern North Pacific Ocean. To investigate the spatial and interannual variability of this springtime feature, multi-platform surveys (23 degrees -33 degreesN, 158 degreesW), including shipboard and satellite measurements, were conducted in April 1998 and 1999 to characterize the hydrographic conditions associated with the large chi gradient. Irradiance and chi data collected during the cruise periods were used in an optical model to compute depth-integrated rates of primary production. The southern portion of both transects resembled the climatological conditions at the Hawai'i Ocean Time-series (HOT) study site, Station ALOHA (22.75 degreesN, 158 degreesW), with two major physical and biological frontal features encountered: 1) the South Subtropical Front (SSTF) in 1998 at 27 degrees -28 degreesN and in 1999 at 32.5 degreesN; and 2) the Subtropical Front (STF) in 1998 at 32 degreesN, which in 1999 had migrated northward out of our study area to similar to 34 degreesN. Integrated chi and primary production both increased at the frontal locations in both years. Increases in surface chi from SeaWiFS and shipboard measurements were not apparent at the SSTF, yet the subsurface chi maximum both shallowed and doubled at this front. In addition, primary production modeled from the satellite chi data did not reflect the smaller mesoscale variability of the SSTF. The increase in surface chi at the STF, however, was clearly recorded in both the satellite and shipboard chi measurements. HPLC pigment analysis was performed for select samples collected during the 1998 cruise and revealed a change in phytoplankton composition at all frontal locations. Specifically, there were distinct increases in the dinoflagellate marker, peridinin, and the diatom marker, fucoxanthin, at the SSTF. The same patterns at the SSTF were observed during both cruises, except all gradients were shifted to the north, as a result of changes in the large-scale circulation of the gyre in 1999. While the eastern equatorial Pacific experienced a dramatic decrease in chi concentrations during El Nino events, the subtropical Pacific appeared to be more 'green' with a southward shift of the circulatory and high surface chl fronts. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Dept Oceanog, Honolulu, HI 96822 USA. Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI USA. RP Leonard, CL (reprint author), Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Dept Oceanog, 1000 Pope Rd, Honolulu, HI 96822 USA. EM carrie@soest.hawaii.edu NR 36 TC 14 Z9 16 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6611 J9 PROG OCEANOGR JI Prog. Oceanogr. PY 2001 VL 49 IS 1-4 SI SI BP 227 EP 244 DI 10.1016/S0079-6611(01)00024-6 PG 18 WC Oceanography SC Oceanography GA 477AU UT WOS:000171261600013 ER PT J AU Polovina, JJ Howell, E Kobayashi, DR Seki, MP AF Polovina, JJ Howell, E Kobayashi, DR Seki, MP TI The transition zone chlorophyll front, a dynamic global feature defining migration and forage habitat for marine resources SO PROGRESS IN OCEANOGRAPHY LA English DT Article; Proceedings Paper CT Conference on Beyond El Nino CY MAR, 2000 CL LA JOLLA, CALIFORNIA ID OCEAN COLOR; PACIFIC AB Pelagic ecosystem dynamics on all temporal scales may be driven by the dynamics of very specialized oceanic habitats. One such habitat is the basin-wide chlorophyll front located at the boundary between the low chlorophyll subtropical gyres and the high chlorophyll subarctic gyres. Global satellite maps of surface chlorophyll clearly show this feature in all oceans. In the North Pacific, the front is over 8000 km long and seasonally migrates north and south about 1000 km. In the winter this front is located at about 30-35 degreesN latitude and in the summer at about 40-45 degreesN. It is a zone of surface convergence where cool, vertically mixed, high chlorophyll, surface water on the north side sinks beneath warm, stratified, low chlorophyll water on the south side. Satellite telemetry data on movements of loggerhead turtles and detailed fisheries data for albacore tuna show that both apex predators travel along this front as they migrate across the North Pacific. The front is easily monitored with ocean color satellite remote sensing. A change in the position of the TZCF between 1997 and 1998 appears Lo have altered the spatial distribution of loggerhead turtles. The position and dynamics of the front varied substantially between the 1998 El Nino and the 1999 La Nina. For example, from May to July 1999 the transition zone chlorophyll front (TZCF) remained between about 35 degreesN and 40 degreesN latitude showing very little meandering, whereas in 1998, during the same period, the TZCF exhibited considerable meandering and greater monthly latitudinal movement. Catch rates for albacore were considerably higher in 1998 than in 1999, and we hypothesize that a meandering TZCF creates regions of convergence, which enhances the foraging habitat for apex predators along the front. Published by Elsevier Science Ltd. C1 NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. Univ Hawaii, Joint Inst Marine & Atmospher Res, Honolulu, HI 96822 USA. RP Polovina, JJ (reprint author), NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, 2570 Dole St, Honolulu, HI 96822 USA. OI Howell, Evan/0000-0001-9904-4633 NR 11 TC 237 Z9 256 U1 3 U2 42 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6611 J9 PROG OCEANOGR JI Prog. Oceanogr. PY 2001 VL 49 IS 1-4 SI SI BP 469 EP 483 DI 10.1016/S0079-6611(01)00036-2 PG 15 WC Oceanography SC Oceanography GA 477AU UT WOS:000171261600025 ER PT B AU Banks, BA Stueber, TJ Norris, MJ AF Banks, BA Stueber, TJ Norris, MJ BE Kleiman, JI Tennyson, RC TI Monte Carlo computational modeling of the energy dependence of atomic oxygen undercutting of protected polymers SO PROTECTION OF SPACE MATERIALS FROM THE SPACE ENVIRONMENT SE SPACE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT 4th International Conference on Protection of Materials from the Space Environment (ICPMSE-4) CY APR 23-24, 1998 CL TORONTO, CANADA AB A Monte Carlo computational model has been developed which simulates atomic oxygen attack of protected polymers at defect sites in the protective coatings. The parameters defining how atomic oxygen interacts with polymers and protective coatings, as well as the scattering processes which occur, have been optimized to replicate experimental results observed from protected polyimide Kapton on the Long Duration Exposure Facility (LDEF) mission. Computational prediction of atomic oxygen undercutting at defect sites in protective coatings for various arrival energies was investigated. The atomic oxygen undercutting energy dependence predictions enable one to predict mass loss that would occur in low Earth orbit, based on lower energy ground laboratory atomic oxygen beam systems. Results of computational model prediction of undercut cavity size as a function of energy and defect size will be presented to provide insight into expected in-space mass loss of protected polymers with protective coating defects based on lower energy ground laboratory testing. C1 NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP Banks, BA (reprint author), NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. NR 18 TC 9 Z9 10 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6981-5 J9 SPACE TECHNOL PROC PY 2001 VL 4 BP 1 EP 14 PG 14 WC Engineering, Aerospace; Astronomy & Astrophysics; Materials Science, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Materials Science GA BS88M UT WOS:000171315800001 ER PT B AU Rutledge, SK Banks, BA Kitral, M AF Rutledge, SK Banks, BA Kitral, M BE Kleiman, JI Tennyson, RC TI A comparison of space- and ground-based facility environmental effects for FEP Teflon SO PROTECTION OF SPACE MATERIALS FROM THE SPACE ENVIRONMENT SE SPACE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT 4th International Conference on Protection of Materials from the Space Environment (ICPMSE-4) CY APR 23-24, 1998 CL TORONTO, CANADA AB Fluorinated Ethylene Propylene (FEP) Teflon (TM) is widely used as a thermal control material for spacecraft. However, it is susceptible to erosion, cracking, and subsequent mechanical failure in low Earth orbit (LEO). One of the difficulties in determining whether FEP Teflon will survive during a mission is the wide disparity of erosion rates observed for this material in space and in ground-based facilities. Each environment contains different levels of atomic oxygen, ions, and vacuum ultraviolet (VUV) radiation, in addition to parameters such as the energy of the arriving species and temperature. These variations make it difficult to determine what is causing the observed differences in erosion rates. This paper attempts to narrow down which factors affect the erosion rate of FEP Teflon through attempting to change only one environmental constituent at a time. This was attempted through the use of a single simulation facility (plasma asher) environment with a variety of Faraday cages and VUV transparent windows. Isolating one factor inside of a radio frequency (RF) plasma proved to be very difficult. Two observations could be made. First, it appears that the erosion yield of FEP Teflon with respect to that of polyimide Kapton is not greatly affected by the presence or lack of VUV radiation present in the RF plasma and the relative erosion yield for the FEP Teflon may decrease with increasing fluence. Second, shielding from charged particles appears to lower the relative erosion yield of the FEP to approximately that observed in space, however it is difficult to determine for sure whether ions, electrons, or some other components are causing the enhanced erosion. C1 NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP Rutledge, SK (reprint author), NASA, Lewis Res Ctr, 21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6981-5 J9 SPACE TECHNOL PROC PY 2001 VL 4 BP 165 EP 179 PG 15 WC Engineering, Aerospace; Astronomy & Astrophysics; Materials Science, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Materials Science GA BS88M UT WOS:000171315800013 ER PT B AU Dever, JA Rutledge, SK Hasegawa, MM Reed, CK AF Dever, JA Rutledge, SK Hasegawa, MM Reed, CK BE Kleiman, JI Tennyson, RC TI Evaluation of low earth orbit environmental effects on International Space Station thermal control materials SO PROTECTION OF SPACE MATERIALS FROM THE SPACE ENVIRONMENT SE SPACE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT 4th International Conference on Protection of Materials from the Space Environment (ICPMSE-4) CY APR 23-24, 1998 CL TORONTO, CANADA AB Samples of International Space Station (ISS) thermal control coatings were exposed to simulated low Earth orbit (LEO) environmental conditions to determine effects on optical properties. In one test, samples of the white paint coating Z-93P were coated, with outgassed products from Tefzel (R) (ethylene tetrafluoroethylene copolymer) power cable insulation as may occur on ISS. These samples were then exposed, along with an uncontaminated Z-93P witness sample, to vacuum ultraviolet (VUV) radiation to determine solar absorptance degradation. The Z-93P samples coated with Tefzel outgassing products experienced greater increases in solar absorptance than witness samples not coated with Tefzel outgassing products. In another test, samples of second surface silvered Teflon (R) FEP (fluorinated ethylene propylene), SiOx (where x approximate to2)-coated silvered Teflon FEP, and Z-93P witness samples were exposed to the combined environments of atomic oxygen and VUV radiation to determine optical properties changes due to these simulated ISS environmental effects. This test verified the durability of these materials in the absence of contaminants. C1 NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP Dever, JA (reprint author), NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. NR 7 TC 0 Z9 0 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6981-5 J9 SPACE TECHNOL PROC PY 2001 VL 4 BP 181 EP 195 PG 15 WC Engineering, Aerospace; Astronomy & Astrophysics; Materials Science, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Materials Science GA BS88M UT WOS:000171315800014 ER PT B AU de Groh, KK Banks, BA Sechkar, EA Scheiman, DA AF de Groh, KK Banks, BA Sechkar, EA Scheiman, DA BE Kleiman, JI Tennyson, RC TI Simulated solar flare X-ray and thermal cycling durability evaluation of hubble space telescope thermal control candidate replacement materials SO PROTECTION OF SPACE MATERIALS FROM THE SPACE ENVIRONMENT SE SPACE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT 4th International Conference on Protection of Materials from the Space Environment (ICPMSE-4) CY APR 23-24, 1998 CL TORONTO, CANADA AB During the Hubble Space Telescope (HST) second servicing mission (SM2), astronauts noticed that the multi-layer insulation (NILI) covering the telescope was damaged, Large pieces of the outer layer of NILI (aluminized Teflon (R) fluorinated ethylene propylene (Al-FEP)) were cracked in several locations around the telescope. A piece of curled-up Al-FEP was retrieved by the astronauts and was found to be severely embrittled, as witnessed by ground testing. The National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) organized an HST NILI Failure Review Board (FRB) to determine the damage mechanism of the Al-FEP in the HST environment, and to recommend a replacement thermal control outer layer material to be installed on HST during the subsequent servicing missions. Candidate thermal control replacement materials were chosen by the FRB and tested for environmental durability under various exposures and durations by GSFC and NASA Lewis Research Center (LeRC). This paper describes durability testing at LeRC of candidate materials which were exposed to charged particle radiation, simulated solar flare X-ray radiation and thermal cycling under load. Samples were evaluated for changes in solar absorptance and tear resistance. Descriptions of environmental exposures and durability evaluations of these materials are presented. C1 NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP de Groh, KK (reprint author), NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6981-5 J9 SPACE TECHNOL PROC PY 2001 VL 4 BP 253 EP 279 PG 27 WC Engineering, Aerospace; Astronomy & Astrophysics; Materials Science, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Materials Science GA BS88M UT WOS:000171315800020 ER PT J AU Mills, PJ Ziegler, MG Fritsch-Yelle, JM Waters, WW D'Aunno, D AF Mills, PJ Ziegler, MG Fritsch-Yelle, JM Waters, WW D'Aunno, D TI The stress of spaceflight and landing lead to a catecholamine-mediated leukocyte redistrubution that is dependent upon mission duration SO PSYCHOSOMATIC MEDICINE LA English DT Meeting Abstract C1 Univ Calif San Diego, Cardiovasc Labs, San Diego, CA 92103 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0033-3174 J9 PSYCHOSOM MED JI Psychosom. Med. PD JAN-FEB PY 2001 VL 63 IS 1 MA 1075 BP 137 EP 137 PG 1 WC Psychiatry; Psychology; Psychology, Multidisciplinary SC Psychiatry; Psychology GA 399ZB UT WOS:000166843200163 ER PT J AU Masci, FJ Condon, JJ Barlow, TA Lonsdale, CJ Xu, C Shupe, DL Pevunova, O Fang, F Cutri, R AF Masci, FJ Condon, JJ Barlow, TA Lonsdale, CJ Xu, C Shupe, DL Pevunova, O Fang, F Cutri, R TI A new complete sample of submillijansky radio sources: An optical and near-infrared study SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID STAR-FORMATION HISTORY; LUMINOSITY FUNCTION; SOURCE COUNTS; STARBURST GALAXIES; NUMBER COUNTS; HIGH-REDSHIFT; VLA SURVEY; DUST; SPECTROSCOPY; GHZ AB The Very Large Array has been used in C configuration to map an area similar or equal to 0.3 deg(2) at 1.4 GHz with 5 sigma sensitivities of 0.305, 0.325, 0.380, and 0.450 mJy beam(-1) over four equal subareas. Radio properties are presented for 62 detected sources. Deep optical imaging to Gunn r similar or equal to 25 mag using the Hale 5 m telescope covering similar or equal to 0. 21 deg(2) is reported for a subset of 43 sources. This optical follow- up is much deeper than that of existing larger area radio surveys of similar radio sensitivity. Archival J-, H-, and K- band photometry from the Two- Micron All Sky Survey is also presented. Using a robust likelihood ratio technique, we optically identified 26 radio sources with probabilities greater than or equal to 80%, nine with uncertain/ ambiguous detections, and eight with empty fields. Comparisons with a stellar synthesis model that includes radio emission and dust reddening suggest that the near- infrared- optical emission in a small, bright subsample is reddened by "optically thin" dust with absorption A(V) similar or equal to 2-2.5 mag, regardless of morphological type. This is consistent with other, more direct determinations of absorption. The radio- optical(- near- infrared) flux ratios of early- type galaxies require significant contamination in the radio by an active galactic nucleus, consistent with the current paradigm. Using our simple modeling approach, we also discuss a potential diagnostic for selecting ultraluminous infrared galaxies to z similar or equal to from microjansky radio surveys. C1 CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. RP Masci, FJ (reprint author), CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, M-S 100-22, Pasadena, CA 91125 USA. EM fmasci@ipac.caltech.edu.au NR 61 TC 11 Z9 11 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD JAN PY 2001 VL 113 IS 779 BP 10 EP 28 DI 10.1086/317978 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 386LG UT WOS:000166062400003 ER PT B AU O'Keeffe, J Mingo, N Han, J AF O'Keeffe, J Mingo, N Han, J BE Cahay, M Leburton, JP Lockwood, DJ Bandyopadhyay, S Harris, JS TI Local distribution of the current flowing between a carbon nanotube and a metal SO QUANTUM CONFINEMENT VI: NANOSTRUCTURED MATERIALS AND DEVICES SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 6th International on Quantum Confinement - Nanostructured Materials and Devices CY SEP 05-06, 2001 CL SAN FRANCISCO, CA SP Electrochem Soc, Dielect Sci & Technol Div, Electrochem Soc, Electr Div, Electrochem Soc, Luminescence & Display Mat Div ID SCANNING TUNNELING MICROSCOPE; CONTACT RESISTANCE; QUANTUM UNIT AB We theoretically study the dependence of the total and local conductances as a molecular size wire is being dipped into a metal. Examples of carbon nanotubes dipped into a free electron metal are analysed. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Mingo, N (reprint author), NASA, Ames Res Ctr, Mail Stop T27A-1, Moffett Field, CA 94035 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-352-0 J9 ELEC SOC S PY 2001 VL 2001 IS 19 BP 23 EP 33 PG 11 WC Electrochemistry; Engineering, Electrical & Electronic; Optics; Physics, Applied SC Electrochemistry; Engineering; Optics; Physics GA BV99J UT WOS:000180622500004 ER PT B AU Yamada, T AF Yamada, T BE Cahay, M Leburton, JP Lockwood, DJ Bandyopadhyay, S Harris, JS TI Transport modeling for metallic electrode - Carbon nanotube systems SO QUANTUM CONFINEMENT VI: NANOSTRUCTURED MATERIALS AND DEVICES SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 6th International on Quantum Confinement - Nanostructured Materials and Devices CY SEP 05-06, 2001 CL SAN FRANCISCO, CA SP Electrochem Soc, Dielect Sci & Technol Div, Electrochem Soc, Electr Div, Electrochem Soc, Luminescence & Display Mat Div ID FIELD-EFFECT TRANSISTORS; SINGLE-WALL; JUNCTIONS; SURFACE AB A model is proposed for two observed current-voltage (I-V) patterns in recent experiment with a scanning tunneling microscope tip and a carbon nanotube [Collins et al., Science 278, 100 (1997)]. We consider that there are two contact modes for a tip (metal)-nanotube (semiconductor) junction depending on whether the alignment of the metal and the semiconductor band structures is (1) variable (vacuum-gap) or (2) fixed (touching) with V With the tip grounded, the tunneling transport in (1) will produce large dI/ dV with V > 0, small dI/dV with V < 0, and I = 0 near V = 0 for an either nor p-nanotube. However, the Schottky transport in (2) will result in forward current with V < 0 for an n-nanotube, while with V > 0 for a p-nanotube. The two observed I-V patterns are thus entirely explained by a tip-nanotube contact of the two types, and the nanotube must be n-type. We apply this model to a long nanotube-channel field-effect-transistor and analyze its I-V characteristics at low temperature. Two independent metal-semiconductor junctions at the source and the drain are responsible for the observed behavior. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Yamada, T (reprint author), NASA, Ames Res Ctr, M-S T27A-1, Moffett Field, CA 94035 USA. NR 28 TC 1 Z9 1 U1 1 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-352-0 J9 ELEC SOC S PY 2001 VL 2001 IS 19 BP 81 EP 87 PG 7 WC Electrochemistry; Engineering, Electrical & Electronic; Optics; Physics, Applied SC Electrochemistry; Engineering; Optics; Physics GA BV99J UT WOS:000180622500008 ER PT J AU Andreev, AA Klimanov, VA Sulerzhitsky, LD AF Andreev, AA Klimanov, VA Sulerzhitsky, LD TI Vegetation and climate history of the Yana River lowland, Russia, during the last 6400 yr SO QUATERNARY SCIENCE REVIEWS LA English DT Article; Proceedings Paper CT Beringian Paleoenvironments Workshop CY 1997 CL BERINGIA, RUSSIA AB New pollen records and radiocarbon dates from two sites in the Yana River lowlands, Arctic Yakutia, Russia provide reconstructions of vegetation and climate history of this region during the last 6400 yr. The fluctuations in pollen and spores reflect the local hydrological events and regional climate changes. The data show that larch (Larix dahurica) forests with shrub alder (Alnus fruticosa) and dwarf birch (Betula exilis) dominated the area during the last 6400 yr BP. There is no evidence for tree-line fluctuations at the sites during the latter half of the Holocene. Climate reconstructions made by transfer function from one site show that the warmest lime was between 6000 and 4500 yr BP. All climate fluctuations reconstructed at this site correspond well with regional climate changes. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Russian Acad Sci, Inst Geog, Moscow 109017, Russia. Russian Acad Sci, Inst Geol, Moscow 109017, Russia. RP Andreev, AA (reprint author), Forsch Stelle Potsdam, Alfred Wegener Inst Polar & Marine Res, Telegrafenberg A43, D-14478 Potsdam, Germany. RI Andreev, Andrei/J-2701-2015 NR 23 TC 25 Z9 29 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0277-3791 J9 QUATERNARY SCI REV JI Quat. Sci. Rev. PD JAN PY 2001 VL 20 IS 1-3 BP 259 EP 266 DI 10.1016/S0277-3791(00)00118-9 PG 8 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 386NK UT WOS:000166068300019 ER PT J AU Wu, HL George, K Kawata, T Willingham, V Cucinotta, FA AF Wu, HL George, K Kawata, T Willingham, V Cucinotta, FA TI Comparison of F ratios generated from interphase and metaphase chromosome damage induced by high doses of low- and high-LET radiation SO RADIATION RESEARCH LA English DT Article ID DENSELY IONIZING-RADIATION; HUMAN-LYMPHOCYTES; FINGERPRINT; ABERRATIONS; CHROMATIN; EXPOSURE; BREAKS AB Although biophysical models predict a difference in the ratio of interchromosomal to intrachromosomal interarm exchanges (F ratio) for low- and high-LET radiations, few experimental data support this prediction. However, the F ratios in experiments to date have been generated using data on chromosome aberrations in samples collected at the first postirradiation mitosis, which may not be indicative of the aberrations formed in interphase after exposure to high-LET radiations. In the present study, we exposed human lymphocytes in vitro to 2 and 5 Gy of gamma rays and 3 Gy of 1 GeV/nucleon iron ions (LET = 140 keV/mum), stimulated the cells to grow with phytohemagglutinin (PHA), and collected the condensed chromosomes after 48 h of incubation using both chemically induced premature chromosome condensation (PCC) and the conventional metaphase techniques. The PCC technique used here condenses chromosomes mostly in the G(2) phase of the cell cycle. The F ratio was calculated using data on asymmetrical chromosome aberrations in both the PCC and metaphase samples. It was found that the F ratios were similar for the samples irradiated with low- and high-LET radiation and collected at metaphase. However, for irradiated samples assayed by PCC, the F ratio was found to be 8.2 +/- 2.0 for 5 Gy gamma rays and 5.2 +/- 0.9 for 3 Gy iron ions. The distribution of the aberrations indicated that, in the PCC samples irradiated with iron ions, most of the centric rings occurred in spreads containing five or more asymmetrical aberrations. These heavily damaged cells, which were either less likely to reach mitosis or may reach mitosis at a later time, were responsible for the difference in the F ratios generated from interphase and metaphase analysis after exposure to iron ions. (C) 2001 by Radiation Research Society. C1 NASA, Lyndon B Johnson Space Ctr, Kelsey Seybold Clin, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. Wyle Lab, Houston, TX 77058 USA. Keio Univ, Dept Radiol, Tokyo, Japan. RP Wu, HL (reprint author), NASA, Lyndon B Johnson Space Ctr, Kelsey Seybold Clin, Mail Code SD23, Houston, TX 77058 USA. NR 16 TC 23 Z9 27 U1 0 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 2001 VL 155 IS 1 BP 57 EP 62 DI 10.1667/0033-7587(2001)155[0057:COFRGF]2.0.CO;2 PN 1 PG 6 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 391TB UT WOS:000166370300008 PM 11121216 ER PT S AU Gorham, PW Liewer, KM Naudet, CJ Saltzberg, DP Williams, D AF Gorham, PW Liewer, KM Naudet, CJ Saltzberg, DP Williams, D BE Saltzberg, D Gorham, P TI New limits on a diffuse flux of >= 100 EeV cosmic neutrinos SO RADIO DETECTION OF HIGH ENERGY PARTICLES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1st International Workshop on Radio Detection of High Energy Particles (RADHEP 2000) CY NOV 16-18, 2000 CL LOS ANGELES, CA SP Univ Calif Los Angeles ID HIGH-ENERGY NEUTRINOS; PULSES AB We report on results from about 30 hours of livetime with the Goldstone Lunar Ultra-high energy neutrino Experiment (GLUE). The experiment searches for similar to 10 ns microwave pulses from tile lunar regolith, appearing in coincidence at two large radio telescopes separated by about 20 km and linked by optical fiber. The pulses can arise from subsurface electromagnetic cascades induced by interactions of up-coming similar to 100 EeV neutrinos in the lunar regolith. A new triggering method implemented after the first 12 hours of livetime has significantly reduced the terrestrial interference background, and we now operate at the thermal noise level. No strong candidates are yet seen, We report on limits implied by this non-detection, based on new Monte Carlo estimates of the efficiency. We also report on preliminary analysis of smaller pulses, where some indications of notitatistical excess may be present. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gorham, PW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 24 TC 15 Z9 15 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0018-0 J9 AIP CONF PROC PY 2001 VL 579 BP 177 EP 188 PG 12 WC Physics, Particles & Fields SC Physics GA BS97M UT WOS:000171562900017 ER PT S AU Gorham, PW AF Gorham, PW BE Saltzberg, D Gorham, P TI On radar detection of EeV air showers SO RADIO DETECTION OF HIGH ENERGY PARTICLES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1st International Workshop on Radio Detection of High Energy Particles (RADHEP 2000) CY NOV 16-18, 2000 CL LOS ANGELES, CA SP Univ Calif Los Angeles AB Extensive air showers produced by EeV cosmic rays leave a significant ionization trail, which may be detectable by radar reflection, by analogy to the way both meteor and lightning ionization trails are presently observed. Such methods could lead to low-cost detection and characterization of events near and above the GZK cutoff. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gorham, PW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 15 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0018-0 J9 AIP CONF PROC PY 2001 VL 579 BP 253 EP 262 PG 10 WC Physics, Particles & Fields SC Physics GA BS97M UT WOS:000171562900024 ER PT S AU Vinogradova, T Chapin, E Gorham, P Saltzberg, D AF Vinogradova, T Chapin, E Gorham, P Saltzberg, D BE Saltzberg, D Gorham, P TI Proposed experiment to detect air showers with the Jicamarca radar system SO RADIO DETECTION OF HIGH ENERGY PARTICLES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1st International Workshop on Radio Detection of High Energy Particles (RADHEP 2000) CY NOV 16-18, 2000 CL LOS ANGELES, CA SP Univ Calif Los Angeles AB When an extremely high energy particle interacts in the atmosphere, the collision induces a multiplicative cascade of charged particles, which grows exponentially until the energy per secondary degrades enough to dissipate in ionization of the surrounding air. During this process the compact cloud of energetic secondary particles travels 10-20 kin through the atmosphere, leaving a column of ionization behind it. This ionized column quickly recombines, but for a period of order 0.1 ms it is highly reflective at frequencies below 100 MHz. This ionization trail, which is comparable in ionization density to that of a micro-meteor. should be clearly detectable using standard radar methods. We. propose radar measurements using the facilities operated by Cornell University and the Instituto Geofisico del Peru (IGP) at the Jicamarca Radio Observatory near Lima, Peru. This facility's primary instrument is 49.92 MHz incoherent scatter radar, transmitting up to 1.5 MW of pulse power. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Vinogradova, T (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 2 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0018-0 J9 AIP CONF PROC PY 2001 VL 579 BP 271 EP 276 PG 6 WC Physics, Particles & Fields SC Physics GA BS97M UT WOS:000171562900026 ER PT S AU Diaz, FRC AF Diaz, FRC BE Mau, TK DeGrassie, J TI An overview of the VASIMR engine: High power space propulsion with RF plasma generation and heating SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 14th Topical Conference on Radio Frequency Power in Plasmas CY MAY 07-09, 2001 CL OXNARD, CA SP Gen Atom, Univ Calif San Diego, Amer Inst Phys AB The Variable Specific Impulse Magnetoplasma Rocket (VASIMR) is a high power, radio frequency-driven magnetoplasma rocket capable of exhaust modulation at constant power. While the plasma is produced by a helicon discharge, the bulk of the energy is added in a separate downstream stage by ion cyclotron resonance heating (ICRH.) Axial momentum is obtained by the adiabatic expansion of the plasma in a magnetic nozzle. Exhaust variation in the VASIMR is primarily achieved by the selective partitioning of the RF power to the helicon and ICRH systems, with the proper adjustment of the propellant flow. However, other complementary techniques are also being studied. Operational and performance considerations favor the light gases. The physics and engineering of this device have been under study since the late 1970s. A NASA-led, research effort, involving several teams in the United States, continues to explore the scientific and technological foundations of this concept. The research involves theory, experiment, engineering design, mission analysis, and technology development. Experimentally, high density, stable plasma discharges have been generated in Helium, Hydrogen and Deuterium, as well as mixtures of these gases. Key issues involve the optimization of the helicon discharge for high-density operation and the efficient coupling of ICRH to the plasma, prior to acceleration by the magnetic nozzle. Theoretically, the dynamics of the magnetized plasma are being studied from kinetic and fluid perspectives. Plasma acceleration by the magnetic nozzle and subsequent detachment has been demonstrated in numerical simulations. These results are presently undergoing experimental verification. A frisk technology development effort for space-qualified, compact, solid-state RF equipment, and high temperature superconducting magnets is under way in support of this project. A Conceptual point design for an early space demonstrator on the International Space Station has been defined. Also a parametric study of a fast (115 day,) VASIMR-driven human Mars mission has been completed. This paper reviews the progress obtained in all these areas and outlines plans and strategies for continued research. C1 NASA, Adv Space Prop Lab, Johnson Space Ctr, Houston, TX 77059 USA. RP Diaz, FRC (reprint author), NASA, Adv Space Prop Lab, Johnson Space Ctr, Houston, TX 77059 USA. NR 9 TC 5 Z9 5 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0038-5 J9 AIP CONF PROC PY 2001 VL 595 BP 3 EP 15 PG 13 WC Physics, Fluids & Plasmas SC Physics GA BT43V UT WOS:000173023300001 ER PT S AU Moss, JN AF Moss, JN BE Bartel, TJ Gallis, MA TI DSMC simulations of shock interactions about sharp double cones SO RAREFIED GAS DYNAMICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 22nd International Symposium on Rarefied Gas Dynamics CY JUL 09-14, 2000 CL SYDNEY, AUSTRALIA SP Sandia Natl Labs, AFOSR/AOARD, ONR IFO Asia, Far E, DLR, USA Res Off, GAB Consulting Pty Ltd, Telstra AB This paper presents the results of a numerical study of shock interactions resulting from Mach 10 flow about sharp double cones. Computations are made by using the direct simulation Monte Carlo (DSMC) method of Bird. The sensitivity and characteristics of the interactions are examined by varying flow conditions, model size, and configuration. The range of conditions investigated includes those for which experiments have been or will be performed in the ONERA R5Ch low-density wind tunnel and the Calspan-University of Buffalo Research Center (CUBRC) Large Energy National Shock (LENS) tunnel. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Moss, JN (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0025-3 J9 AIP CONF PROC PY 2001 VL 585 BP 691 EP 698 PG 8 WC Physics, Fluids & Plasmas SC Physics GA BT38R UT WOS:000172834300093 ER PT S AU Glass, CE Gnoffo, PA AF Glass, CE Gnoffo, PA BE Bartel, TJ Gallis, MA TI A 3-D coupled CFD-DSMC solution method with application to the Mars Sample Return Orbiter SO RAREFIED GAS DYNAMICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 22nd International Symposium on Rarefied Gas Dynamics CY JUL 09-14, 2000 CL SYDNEY, AUSTRALIA SP Sandia Natl Labs, AFOSR/AOARD, ONR IFO Asia, Far E, DLR, USA Res Off, GAB Consulting Pty Ltd, Telstra ID SIMULATION MONTE-CARLO; BODY WAKE FLOWS AB A method to obtain coupled CFD-DSMC, 3-D flow field solutions for highly blunt bodies at low incidence is presented and applied to one concept of the Mars Sample Return Orbiter vehicle as a demonstration of the technique. CFD is used to solve the high-density blunt forebody flow defining an inflow boundary condition for a DSMC solution of the afterbody wake flow. By combining the two techniques in flow regions where most applicable, the entire mixed flow field is modeled in an appropriate manner. C1 NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. RP Glass, CE (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0025-3 J9 AIP CONF PROC PY 2001 VL 585 BP 723 EP 729 PG 7 WC Physics, Fluids & Plasmas SC Physics GA BT38R UT WOS:000172834300097 ER PT S AU Gizon, L Duvall, TL Larsen, RM AF Gizon, L Duvall, TL Larsen, RM BE Brekke, P Fleck, B Gurman, JB TI Probing surface flows and magnetic activity with time-distance helioseismology SO RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 24th General Assembly of the International-Astronomical-Union CY AUG 07-18, 2000 CL MANCHESTER, ENGLAND SP Int Astron Union ID REGIONS AB We estimate near-surface flows using the techniques of f-mode time-distance helioseismology together with MDI/SOHO data. (1) Synoptic maps of horizontal flows are obtained for 1996, 1998 and 1999. Rotation, torsional oscillations and meridional circulation are measured. We detect weak large-scale flows converging toward active regions. Travel times are found to be shorter at locations of high magnetic activity. In addition, we measure the motion of the supergranulation pattern. (2) Realistic travel-time sensitivity kernels are used in an iterative deconvolution to infer horizontal flows at a high spatial resolution. The radial outflow outside a sunspot penumbra, called the moat, is measured. C1 Stanford Univ, HEPL, Stanford, CA 94305 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Stanford Univ, SCCM, Stanford, CA 94305 USA. RP Gizon, L (reprint author), Stanford Univ, HEPL, Stanford, CA 94305 USA. RI Gizon, Laurent/B-9457-2008; Duvall, Thomas/C-9998-2012 NR 9 TC 4 Z9 4 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-069-2 J9 IAU SYMP PY 2001 IS 203 BP 189 EP 191 PG 3 WC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences GA BU43X UT WOS:000175997400034 ER PT S AU Ireland, J Fludra, A AF Ireland, J Fludra, A BE Brekke, P Fleck, B Gurman, JB TI EUV line intensities and the magnetic field in solar active regions SO RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 24th General Assembly of the International-Astronomical-Union CY AUG 07-18, 2000 CL MANCHESTER, ENGLAND SP Int Astron Union ID ULTRAVIOLET AB The Coronal Diagnostic Spectrometer (CDS) on SOHO carries out daily synoptic observations of the Sun in four EUV (extreme ultraviolet) spectra : He 1 584 Angstrom, 0 V 630 Angstrom, Mg IX 368 Angstrom and Fe XVI 360 A, over a 4 arcmin-wide strip along the solar central meridian. Using 53 active regions observed in this data set along with co-temporally observed SOHO-MDI (Michelson Doppler Imager) magnetograms we study the correlation of the chromospheric, transition region and coronal emission with the photospheric magnetic field for meridional active regions, probing the relation between the radiative output and magnetic observables. We also establish empirical, quantitative relations among intensities of different lines, and between intensities and the magnetic field flux. C1 NASA, Goddard Space Flight Ctr, ESA, Greenbelt, MD 20771 USA. Rutherford Appleton Lab, Space Sci & Technol Dept, Didcot OX11 0QX, Oxon, England. RP Ireland, J (reprint author), NASA, Goddard Space Flight Ctr, ESA, Mailcode 682-3,Bldg 26, Greenbelt, MD 20771 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-069-2 J9 IAU SYMP PY 2001 IS 203 BP 276 EP 279 PG 4 WC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences GA BU43X UT WOS:000175997400058 ER PT S AU Schmieder, B van Driel-Gesztelyi, L Delannee, C Simnett, GM Wiik, JE AF Schmieder, B van Driel-Gesztelyi, L Delannee, C Simnett, GM Wiik, JE BE Brekke, P Fleck, B Gurman, JB TI The relationship between CMEs and prominence eruptions SO RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 24th General Assembly of the International-Astronomical-Union CY AUG 07-18, 2000 CL MANCHESTER, ENGLAND SP Int Astron Union ID SOHO AB We have studied the temporal relationship between three selected prominence eruptions and their associated coronal mass ejections (CME). For these three events it is not possible to predict from the CME time history when the prominence would erupt. However, both are signatures of destabilisation of the global coronal magnetic field. The lack of a precise temporal relationship reflects the fact that several coronal stuctures are destabilised, and in general one will predominate in the CME structure. If this structure happens to be the same as that constraining the prominence, then the latter will erupt following the launch of the CME. If the prominence is constrained by a separate magnetic structure, then it may erupt before or after the main CME. Reconfiguration of the global coronal field probably drives a fast increase of the poloidal field in the prominence flux tube or introduces destabilising shear forces. Events on May 1, 1996, September 25-27, 1996, and May 31 1997 are discussed. C1 Observ Paris, F-92195 Meudon, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. Univ Oslo, Inst Astrophys, Blindern, Norway. RP Schmieder, B (reprint author), Observ Paris, F-92195 Meudon, France. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-069-2 J9 IAU SYMP PY 2001 IS 203 BP 310 EP 313 PG 4 WC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences GA BU43X UT WOS:000175997400068 ER PT S AU Yokoyama, T Akita, K Morimoto, T Inoue, K Newmark, J AF Yokoyama, T Akita, K Morimoto, T Inoue, K Newmark, J BE Brekke, P Fleck, B Gurman, JB TI Observation of reconnection inflow of a solar flare SO RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 24th General Assembly of the International-Astronomical-Union CY AUG 07-18, 2000 CL MANCHESTER, ENGLAND SP Int Astron Union AB We find an important piece of evidence for magnetic reconnection inflow in a flare on March 18, 1999. The flare occurred on the north-east limb, displaying a nice cusp-shaped soft X-ray loop and a plasmoid ejection typical for the long-duration-events. As the plasmoid is ejected, magnetic reconnection occurs at the disconnecting point. A clear ingoing pattern toward the magnetic X-point is seen. The velocity of this apparent motion is about 5 km sec(-1), which is an upper limit on reconnection inflow speed. Based on this observation, we derive the reconnection rate as M-A = 0.001 - 0.03, where M-A is a Alfven Mach number of the inflow. C1 Nobeyama Radio Observ, Natl Astron Observ Japan, Minamimaki, Tochigi 3841305, Japan. Osaka Gakuin Univ, Suita, Osaka 5648511, Japan. Kyoto Univ, Kyoto 6068502, Japan. NASA, Goddard Space Flight Ctr, Emergent Informat Technol East, Greenbelt, MD 20771 USA. RP Yokoyama, T (reprint author), Nobeyama Radio Observ, Natl Astron Observ Japan, Minamimaki, Tochigi 3841305, Japan. RI Yokoyama, Takaaki/B-9315-2008 OI Yokoyama, Takaaki/0000-0001-5457-4999 NR 4 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-069-2 J9 IAU SYMP PY 2001 IS 203 BP 344 EP 346 PG 3 WC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences GA BU43X UT WOS:000175997400078 ER PT S AU Haugan, SVH AF Haugan, SVH BE Brekke, P Fleck, B Gurman, JB TI Anomalous line shifts on the SOHO/CDS NIS detector SO RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 24th General Assembly of the International-Astronomical-Union CY AUG 07-18, 2000 CL MANCHESTER, ENGLAND SP Int Astron Union AB Observations with the SOHO/CDS NIS detector prior to the recovery of SOHO showed strong correlations between line shifts and local intensity gradients along the slit, probably caused by an elliptical, tilted point spread function. This must be taken into account when interpreting NIS observations with strong intensity gradients. An initial analysis of post-recovery data does not display the same pattern, indicating that this particular problem was eliminated by changes in the optics during SOHO's "vacation". C1 NASA, Goddard Space Flight Ctr, ESA, Dept Space Sci, Greenbelt, MD 20771 USA. RP Haugan, SVH (reprint author), NASA, Goddard Space Flight Ctr, ESA, Dept Space Sci, Mail Code 682-3,Bldg 26,room G-1, Greenbelt, MD 20771 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-069-2 J9 IAU SYMP PY 2001 IS 203 BP 396 EP 400 PG 5 WC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences GA BU43X UT WOS:000175997400091 ER PT S AU van Driel-Gesztelyi, L Demoulin, P Ireland, J Thompson, B Fludra, A Olah, K Kovari, Z Harra, LK Mandrini, CH Bocchialini, K Orlando, S AF van Driel-Gesztelyi, L Demoulin, P Ireland, J Thompson, B Fludra, A Olah, K Kovari, Z Harra, LK Mandrini, CH Bocchialini, K Orlando, S BE Brekke, P Fleck, B Gurman, JB TI An observational test for solar atmospheric heating SO RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 24th General Assembly of the International-Astronomical-Union CY AUG 07-18, 2000 CL MANCHESTER, ENGLAND SP Int Astron Union AB We study the evolution of the emissivity correlated with magnetic flux density of an active region from its birth until its decay throughout all atmospheric layers. We analyse multi-wavelength data obtained from SOHO, Yohkoh, GOES, SOLSTICE and 10.7 cm radio data from DRAO, Canada. We utilise our results to understand the scaling laws in different atmospheric layers. We confirm that the relationship between the emitted excess flux (flux-basal flux) and photospheric magnetic flux density DeltaF(< fB >) follow power laws, and the powers depend on the formation temperature of the line(s) involved. C1 Observ Paris, DASOP, F-92195 Meudon, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Konkoly Observ Budapest, H-1525 Budapest, Hungary. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Inst Astron & Fis Espacio, RA-1428 Buenos Aires, DF, Argentina. Univ Paris 11, IAS, Paris, France. RP van Driel-Gesztelyi, L (reprint author), Observ Paris, DASOP, F-92195 Meudon, France. RI Thompson, Barbara/C-9429-2012; OI Kovari, Zsolt/0000-0001-5160-307X NR 4 TC 0 Z9 0 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-069-2 J9 IAU SYMP PY 2001 IS 203 BP 514 EP 516 PG 3 WC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences GA BU43X UT WOS:000175997400119 ER PT J AU Lenoir, B Scherrer, H Caillat, T AF Lenoir, B Scherrer, H Caillat, T TI An overview of recent developments for BiSb alloys SO RECENT TRENDS IN THERMOELECTRIC MATERIALS RESEARCH I SE SEMICONDUCTORS AND SEMIMETALS LA English DT Article ID BI0.96SB0.04 ALLOYS; BI1-XSBX ALLOYS; HOLE TRANSPORT; BISMUTH; GROWTH; CRYSTALS; ELECTRON C1 Ecole Mines, Phys Mat Lab, F-54042 Nancy, France. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Lenoir, B (reprint author), Ecole Mines, Phys Mat Lab, F-54042 Nancy, France. NR 118 TC 20 Z9 21 U1 8 U2 21 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0080-8784 J9 SEMICONDUCT SEMIMET PY 2001 VL 69 BP 101 EP 137 PG 37 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BR34J UT WOS:000166169700004 ER PT S AU Meier, DL AF Meier, DL BE Wheeler, JC Martel, H TI Jet power and jet suppression: The role of disk structure and black hole rotation SO RELATIVISTIC ASTROPHYSICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 20th Texas Symposium on Relativistic Astrophysics CY DEC 10-15, 2000 CL AUSTIN, TX SP Natl Sci Fdn, NASA, US DOE, Univ Texas Austin, Off Vice President Res, Univ Texas Austin, Coll Natl Sci, Univ Texas Austin, Dept Astronom, Univ Texas Austin, McDonald Observ ID HARD X-RAY; GALAXIES; FANAROFF; BEHAVIOR AB I review a model in which the strongest radio-emitting jets are produced by black hole systems only when the accretion flow is both geometrically thick and the black hole is rotating rapidly. The model accounts for the radio powers of the strongest extragalactic sources and explains the correlation between radio jet power and accretion disk state seen in galactic black hole candidate sources. It appears unlikely that an ADAF-accreting Schwarzschild black hole will be able to produce a strong jet, despite the possibility of an inner rotationally-supported disk near the last stable orbit; the poloidal magnetic field will not be strong enough in that region. Comparison of these theoretical results with a radio power/black hole mass relation recently derived for quasars suggests that more massive black holes (e.g., bright quasars) may be rotating more rapidly than less massive ones (e.g., Seyfert galaxies). C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Meier, DL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0026-1 J9 AIP CONF PROC PY 2001 VL 586 BP 420 EP 425 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT35V UT WOS:000172735600062 ER PT S AU Weaver, KA AF Weaver, KA BE Wheeler, JC Martel, H TI Probing black holes with constellation-X SO RELATIVISTIC ASTROPHYSICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 20th Texas Symposium on Relativistic Astrophysics CY DEC 10-15, 2000 CL AUSTIN, TX SP Natl Sci Fdn, NASA, US DOE, Univ Texas Austin, Off Vice President Res, Univ Texas Austin, Coll Natl Sci, Univ Texas Austin, Dept Astronom, Univ Texas Austin, McDonald Observ ID GALAXY MCG-6-30-15; DISK; VARIABILITY; ASCA AB Constellation-X is a premiere X-ray spectroscopy mission due to launch within the next decade. With a factor of 100 increase in sensitivity over current Xray spectroscopy missions and an excellent energy resolution of 2 eV at 6 keV, one of the prime science goals of the mission will be to observe activity near the black hole event horizon by measuring changes in the Fe K alpha fluorescence emission line profile and time-linked intensity changes between the line and the continuum. Detailed variability studies with Constellation-X will allow us to reconstruct "images" of the accretion disk, probe the effects of strong gravity in the vicinity of black holes and measure black hole mass and spin via deconvolution of the line profile. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Weaver, KA (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. NR 13 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0026-1 J9 AIP CONF PROC PY 2001 VL 586 BP 702 EP 704 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT35V UT WOS:000172735600118 ER PT S AU Mueller, J Yang, EH Green, A White, V Chakraborty, I Reinicke, R AF Mueller, J Yang, EH Green, A White, V Chakraborty, I Reinicke, R BE Ramesham, R TI Design and fabrication of MEMS-based micropropulsion devices at JPL SO RELIABILITY, TESTING AND CHARACTERIZATION OF MEMS/MOEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability, Testing, and Characterization of MEMS/MOEMS CY OCT 22-24, 2001 CL SAN FRANCISCO, CA SP SPIE DE micropropulsion; microvalves; microfabrication; microspacecraft AB The development and fabrication of microfabricated propulsion components at the Jet Propulsion Laboratory (JPL) is reviewed. These include a vaporizing liquid micro-thruster (VLM), which vaporizes propellant to produce thrust. Thrust performances of 32 muN for an input power of 0.8 W were measured. Miniature solenoid and latch valves are being developed by Moog, Inc. in collaboration with JPL. Although metal-based, these valves employ batch fabrication approaches in their design. A valve prototype 1 cm(3) in size and weighing 7 gram was recently manufactured by Moog. This valve has a power requirement (holding power) of 0.7 W, a 5-V operating voltage, and response times of 1.5 ms (open) and 0.5 ms (close). In a lifetest at Moog this valve reached 1,000,000 cycles. A piezoelectrically actuated microvalve is being developed at JPL. The device is still in early development, however, initial testing showed leak rates as low as 0.001 sccm N-2 at pressures between 10-100 psig. A micro-isolation valve being developed at JPL is aimed at isolating propulsion systems prior to their use. This one-time opening valve can be actuated with 0.01 J within 0.1 ms. This valve, fabricated entirely from silicon and Pyrex, reaches burst pressures as high as 3,000 psia. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Mueller, J (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. OI Yang, Eui-Hyeok/0000-0003-4893-1691 NR 11 TC 4 Z9 4 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4286-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4558 BP 57 EP 71 DI 10.1117/12.443018 PG 15 WC Materials Science, Characterization & Testing SC Materials Science GA BT48E UT WOS:000173103600009 ER PT B AU Kinne, S Holben, B Eck, T Smirnov, A Dubovik, O Slutsker, I Tanre, D Zibozdi, G Lohmann, U Ghan, S Easter, R Chin, M Ginoux, P Takemura, T Tegen, I Koch, D Kahn, R Vermote, E Stowe, L Torres, O Mishchenko, M Geogdzhayev, I Hiragushi, A AF Kinne, S Holben, B Eck, T Smirnov, A Dubovik, O Slutsker, I Tanre, D Zibozdi, G Lohmann, U Ghan, S Easter, R Chin, M Ginoux, P Takemura, T Tegen, I Koch, D Kahn, R Vermote, E Stowe, L Torres, O Mishchenko, M Geogdzhayev, I Hiragushi, A BE Beniston, M Verstraete, MM TI How well do aerosol retrievals from satellites and representation in global circulation models match ground-based AERONET aerosol statistics? SO REMOTE SENSING AND CLIMATE MODELING: SYNERGIES AND LIMITATIONS SE ADVANCES IN GLOBAL CHANGE RESEARCH LA English DT Proceedings Paper CT Workshop on Satellite Remote Sensing and Climate Simulations CY SEP 20-24, 1999 CL LES DIABLERETS, SWITZERLAND SP ENAMORS, Swiss Natl Sci Fdn ID TROPOSPHERIC AEROSOLS; SULFATE AEROSOLS; SAHARAN DUST; SKY RADIANCE; SPACE; EXTINCTION; NETWORK; SMOKE; LAND AB Statistics from sky/sunphotometers at AERONET sites throughout the world provide the background for a comparison of monthly or seasonally averaged aerosol optical depths to retrievals by operational satellites and to representations in global models. Available data-sets, however, rarely relate to the same year(s). With strong year-to-year variations even for monthly averaged aerosol optical depths and open issues on sampling biases and regional representation by local measurements only larger discrepancies are investigated. Aerosol optical depths retrievals of five different satellites and five different global models are compared. Quantitative accurate satellite retrievals over land remain a challenge and even their relative difference cannot provide clear answers on regional representation. Model predicted aerosol optical depth averages are usually smaller than AERONET. The behavior of models is further explored on a component basis. For sulfate, dust, carbon and sea-salt optical depths, mass and assumed aerosol sizes are compared. For the conversion of the column (dry) component mass in optical depth in models, assumptions for component aerosol size and aerosol humidification are critical. Statistical comparisons to ground-based monitoring will be more useful, if temporal differences are removed. This requires data from the same time-period and the use of sampling screens, to accommodate less frequent measurements. For the understanding of regional representation by local measurements, satellite data play a key role. Necessities to validate critical aerosol assumptions in models or satellite retrievals require field- experiments that focus on individual aerosol components plus continued and additional monitoring (e.g. AERONET) at sites, where a particular aerosol component dominates. C1 NASA, Goddard Space Flight Ctr, UMBC, JCET, Greenbelt, MD 20771 USA. RP Kinne, S (reprint author), NASA, Goddard Space Flight Ctr, UMBC, JCET, Greenbelt, MD 20771 USA. RI Dubovik, Oleg/A-8235-2009; Smirnov, Alexander/C-2121-2009; ECK, THOMAS/D-7407-2012; Takemura, Toshihiko/C-2822-2009; Vermote, Eric/K-3733-2012; Chin, Mian/J-8354-2012; Kahn, Ralph/D-5371-2012; Torres, Omar/G-4929-2013; Mishchenko, Michael/D-4426-2012; Ghan, Steven/H-4301-2011 OI Dubovik, Oleg/0000-0003-3482-6460; Smirnov, Alexander/0000-0002-8208-1304; Takemura, Toshihiko/0000-0002-2859-6067; Kahn, Ralph/0000-0002-5234-6359; Ghan, Steven/0000-0001-8355-8699 NR 55 TC 12 Z9 11 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6801-0 J9 ADV GLOB CHANGE RES PY 2001 VL 7 BP 103 EP 158 PG 56 WC Geography, Physical; Meteorology & Atmospheric Sciences; Remote Sensing SC Physical Geography; Meteorology & Atmospheric Sciences; Remote Sensing GA BS25L UT WOS:000169197900006 ER PT S AU Chang, A Chiu, L AF Chang, A Chiu, L BE Owe, M Braubaker, K Ritchie, J Rango, A TI Monthly oceanic rainfall derived from space-borne microwave data SO REMOTE SENSING AND HYDROLOGY 2000 SE IAHS PUBLICATION LA English DT Proceedings Paper CT International Symposium on Remote Sensing and Hydrology 2000 CY APR 02-07, 2000 CL SANTA FE, NM SP Int Commiss Remote Sensing, Int Assoc Hydrol Sci DE microwave radiometer; precipitation; SSM/I; TMI; TRMM AB A technique for estimating monthly oceanic rainfall rate using multi-channel microwave measurements has been in use for over ten years. A modified version of this algorithm is now being applied to the TRMM (Tropical Rainfall Measuring Mission) Microwave Imager (TMI) data. There are three prominent features to this algorithm. First, knowledge of the form of the rainfall intensity probability density function is used to augment the measurements in rain retrieval. Second, utilizing a linear combination of the 19.4 and 21.3 GHz channels, the effect of water vapour is de-emphasized. Third, an objective technique is used to estimate the rain layer thickness from the 19.4 and 21.3 GHz brightness temperature histograms. One year of rainfall data (January-December 1998) is used in this study. The mean differences of TMI and SSM/I (Special Sensor Microwave/Imager) rain estimates are typically less than 15%. The differences are discussed in the context of radiative transfer calculations and the rainfall estimate algorithm. C1 NASA, Hydrol Sci Branch, Lab Hydrospher Proc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Chang, A (reprint author), NASA, Hydrol Sci Branch, Lab Hydrospher Proc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU INT ASSOC HYDROLOGICAL SCIENCES PI WALLINGFORD PA INST OF HYDROLOGY, WALLINGFORD OX10 8BB, ENGLAND SN 0144-7815 BN 1-901502-46-5 J9 IAHS-AISH P PY 2001 IS 267 BP 22 EP 26 PG 3 WC Engineering, Civil; Remote Sensing; Water Resources SC Engineering; Remote Sensing; Water Resources GA BT42U UT WOS:000172971600004 ER PT S AU Fisher, B Wolff, DB Amitai, E AF Fisher, B Wolff, DB Amitai, E BE Owe, M Braubaker, K Ritchie, J Rango, A TI Analytical software for validating time synchronous radar and raingauge data SO REMOTE SENSING AND HYDROLOGY 2000 SE IAHS PUBLICATION LA English DT Proceedings Paper CT International Symposium on Remote Sensing and Hydrology 2000 CY APR 02-07, 2000 CL SANTA FE, NM SP Int Commiss Remote Sensing, Int Assoc Hydrol Sci DE bulk-adjustment; radar-gauge quality control; radar-gauge validation; RRGAT AB Validation studies that compare radar and gauge data are often skewed due to poor data quality. The Tropical Rainfall Measuring Mission (TRMM) Global Validation (GV) Programme uses regional gauge networks to compute corrections to a standard reflectivity-rain rate (Z-R) relationship. This bulk adjustment scheme requires quality gauge and radar data as input. In support of this operational effort, a software package called the Radar Rain Gauge Analysis Tool (RRGAT) was developed to ingest gauge time series data and full radar volume scans for graphical analysis. RRGAT was designed to allow users to compare individual gauge time series with the radar data over a small areal region (6 x 6 km) centred on the gauge. C1 NASA, SSAI Corp, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fisher, B (reprint author), NASA, SSAI Corp, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU INT ASSOC HYDROLOGICAL SCIENCES PI WALLINGFORD PA INST OF HYDROLOGY, WALLINGFORD OX10 8BB, ENGLAND SN 0144-7815 BN 1-901502-46-5 J9 IAHS-AISH P PY 2001 IS 267 BP 27 EP 31 PG 3 WC Engineering, Civil; Remote Sensing; Water Resources SC Engineering; Remote Sensing; Water Resources GA BT42U UT WOS:000172971600005 ER PT S AU Amitai, E Wolff, DB Robinson, M Marks, DA Kulie, MS Ferrier, BS AF Amitai, E Wolff, DB Robinson, M Marks, DA Kulie, MS Ferrier, BS BE Owe, M Braubaker, K Ritchie, J Rango, A TI Systematic variations of Z(e)-R relations: implications for hydrology SO REMOTE SENSING AND HYDROLOGY 2000 SE IAHS PUBLICATION LA English DT Proceedings Paper CT International Symposium on Remote Sensing and Hydrology 2000 CY APR 02-07, 2000 CL SANTA FE, NM SP Int Commiss Remote Sensing, Int Assoc Hydrol Sci DE PMM; precipitation; radar; rain rate; rainfall classification; rainfall estimates; raingauge; reflectivity; Z-R ID RADAR; WPMM AB Radar estimates of precipitation depend on the relations between the radar observed reflectivity (Z(e)) and surface rainfall rate (R). The dependence of the relations on the method used to relate Z(e) to R, and on the rain type was investigated. While probability matching method (PMM) based Z(e)-R curves demonstrated systematic variation between convective and stratiform rain, power law based Z(e)-R curves showed no systematic trend, and in a few cases were found to be the same for both rain types. Over a large time-space domain both methods will result in similar rainfall estimates since the radar observations are tuned to the monthly gauge network accumulation. However, for many hydrological applications, where the rain intensities or the rain depth over a small time-space domain is of great concern, the application of a power law based Z(e)-R will yield systematic estimation errors. C1 Univ Maryland Baltimore Cty, JCET, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Amitai, E (reprint author), Univ Maryland Baltimore Cty, JCET, NASA, Goddard Space Flight Ctr, Mail Code 912-1, Greenbelt, MD 20771 USA. RI Kulie, Mark/C-3289-2011 OI Kulie, Mark/0000-0003-1400-1007 NR 4 TC 0 Z9 0 U1 0 U2 0 PU INT ASSOC HYDROLOGICAL SCIENCES PI WALLINGFORD PA INST OF HYDROLOGY, WALLINGFORD OX10 8BB, ENGLAND SN 0144-7815 BN 1-901502-46-5 J9 IAHS-AISH P PY 2001 IS 267 BP 43 EP 45 PG 3 WC Engineering, Civil; Remote Sensing; Water Resources SC Engineering; Remote Sensing; Water Resources GA BT42U UT WOS:000172971600010 ER PT S AU Hall, DK Riggs, GA Salomonson, VV Scharfen, GR AF Hall, DK Riggs, GA Salomonson, VV Scharfen, GR BE Owe, M Braubaker, K Ritchie, J Rango, A TI Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS) global snow-cover maps SO REMOTE SENSING AND HYDROLOGY 2000 SE IAHS PUBLICATION LA English DT Proceedings Paper CT International Symposium on Remote Sensing and Hydrology 2000 CY APR 02-07, 2000 CL SANTA FE, NM SP Int Commiss Remote Sensing, Int Assoc Hydrol Sci DE Earth Observing System; satellite snow mapping; snow cover AB Following the 1999 launch of the Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS), the capability exists to produce global snow-cover maps on a daily basis at 500 m resolution. Eight-day composite snow-cover maps are also available. The snow maps are also produced at a spatial resolution of 1/4degrees x 1/4degrees, and enhancements are available that provide information on sub-pixel (fractional) snow cover. MODIS snow-cover products are produced at Goddard Space Flight Center and archived and distributed by the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado. The products are produced in both orbital and gridded formats. An online search and order toot and user-services staff are available at NSIDC to assist users with the snow products. Pre-launch validation work has shown that snow-mapping algorithms perform best under conditions of continuous snow cover in low vegetation areas, but can also map snow cover in dense forests. Post-launch validation activities are being performed using field and aircraft measurements from a March 2000 validation mission, as well as from existing satellite-derived snow-cover maps from NOAA and Landsat-7 Enhanced Thematic Mapper Plus (ETM+). C1 NASA, Hydrol Sci Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hall, DK (reprint author), NASA, Hydrol Sci Branch, Goddard Space Flight Ctr, Code 974, Greenbelt, MD 20771 USA. RI Hall, Dorothy/D-5562-2012 NR 13 TC 2 Z9 2 U1 0 U2 1 PU INT ASSOC HYDROLOGICAL SCIENCES PI WALLINGFORD PA INST OF HYDROLOGY, WALLINGFORD OX10 8BB, ENGLAND SN 0144-7815 BN 1-901502-46-5 J9 IAHS-AISH P PY 2001 IS 267 BP 55 EP 60 PG 4 WC Engineering, Civil; Remote Sensing; Water Resources SC Engineering; Remote Sensing; Water Resources GA BT42U UT WOS:000172971600013 ER PT S AU Pinheiro, AC Tucker, CJ Entekhabi, D Privette, JL Berry, JA AF Pinheiro, AC Tucker, CJ Entekhabi, D Privette, JL Berry, JA BE Owe, M Braubaker, K Ritchie, J Rango, A TI Assessing the relationship between surface temperature and soil moisture in southern Africa SO REMOTE SENSING AND HYDROLOGY 2000 SE IAHS PUBLICATION LA English DT Proceedings Paper CT International Symposium on Remote Sensing and Hydrology 2000 CY APR 02-07, 2000 CL SANTA FE, NM SP Int Commiss Remote Sensing, Int Assoc Hydrol Sci DE SAFARI 2000; SAVE, soil moisture; southern Africa; surface temperature; thermal inertia AB Droughts have important implications for the natural and socioeconomic environments of southern Africa. An understanding of the relationship between soil moisture content and vegetation condition is necessary to predict the impact of those events. In this paper we explore a methodological approach for early drought prediction. We hypothesize that the amplitude of the diurnal temperature cycle of a vegetated surface, determined using remote sensing measurements. can indicate soil moisture content and vegetation condition. We present a preliminary analysis of three months of soil moisture and temperature data collected at Skukuza, South Africa. The results support our basic hypothesis yet suggest that further work is required to better understand the coupling of these parameters. The SiB2 model will be adapted for this purpose. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Pinheiro, AC (reprint author), NASA, Goddard Space Flight Ctr, Code 923, Greenbelt, MD 20771 USA. NR 4 TC 1 Z9 1 U1 0 U2 1 PU INT ASSOC HYDROLOGICAL SCIENCES PI WALLINGFORD PA INST OF HYDROLOGY, WALLINGFORD OX10 8BB, ENGLAND SN 0144-7815 BN 1-901502-46-5 J9 IAHS-AISH P PY 2001 IS 267 BP 296 EP 301 PG 2 WC Engineering, Civil; Remote Sensing; Water Resources SC Engineering; Remote Sensing; Water Resources GA BT42U UT WOS:000172971600061 ER PT S AU Owe, M AF Owe, M BE Owe, M Braubaker, K Ritchie, J Rango, A TI Estimating long term surface soil moisture from satellite microwave observations in Illinois, USA SO REMOTE SENSING AND HYDROLOGY 2000 SE IAHS PUBLICATION LA English DT Proceedings Paper CT International Symposium on Remote Sensing and Hydrology 2000 CY APR 02-07, 2000 CL SANTA FE, NM SP Int Commiss Remote Sensing, Int Assoc Hydrol Sci DE microwave; optical depth; remote sensing; SMMR; soil moisture ID VEGETATION; MODEL AB A database of long-term soil moisture was compared to satellite microwave observations over a test site in the midwestern United States. Night-time microwave brightness temperatures were observed at a frequency of 6.6 GHz by the Scanning Multichannel Microwave Radiometer (SMMR). At 6.6 GHz, the instrument provides a spatial resolution of approximately 150 km, and a temporal frequency over the test area of about two to three night-time orbits per week. Vegetation radiative transfer characteristics, such as the canopy transmissivity, were estimated from vegetation indices such as the NDVI and the MPDI. Because the time of satellite coverage does not always coincide with the ground measurements of soil moisture, the existing ground data were used to calibrate a water balance for the top 10 cm surface soil layer in order to interpolate daily surface moisture values. Passive microwave remote sensing presents the greatest potential for providing regular spatially representative estimates of surface soil moisture at global scales. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Owe, M (reprint author), NASA, Goddard Space Flight Ctr, MC 974, Greenbelt, MD 20771 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU INT ASSOC HYDROLOGICAL SCIENCES PI WALLINGFORD PA INST OF HYDROLOGY, WALLINGFORD OX10 8BB, ENGLAND SN 0144-7815 BN 1-901502-46-5 J9 IAHS-AISH P PY 2001 IS 267 BP 394 EP 399 PG 2 WC Engineering, Civil; Remote Sensing; Water Resources SC Engineering; Remote Sensing; Water Resources GA BT42U UT WOS:000172971600081 ER PT S AU Owe, M de Jeu, R Van de Griend, A AF Owe, M de Jeu, R Van de Griend, A BE Owe, M DUrso, G Zilioli, E TI A methodology for estimating surface soil temperature from high frequency microwave observations SO REMOTE SENSING FOR AGRICULTURE, ECOSYSTEMS, AND HYDROLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Remote Sensing for Agriculture, Ecosystems, and Hydrology II CY SEP 25-27, 2000 CL BARCELONA, SPAIN SP European Opt Soc, SPIE, NASA DE remote sensing; brightness temperature; emissivity; surface temperature ID MOISTURE AB A methodology for deriving spatially averaged emitting layer temperature from high frequency microwave observations is presented. Microwave brightness temperature is a function of the emissivity and the physical temperature of the emitting soil layer, thereby possessing a strong physical basis for estimating soil temperature. Field observations have shown that maximum and minimum daily air temperatures are strongly related to midday and midnight surface soil temperature. Field measurements of surface temperature are also compared to METEOSAT thermal observations. Long term daily maximum and minimum air temperatures are used to derive data sets of daytime and nighttime surface temperatures. Results indicate that 37 GHz vertical polarization brightness temperature provides a reasonable estimate of the emitting layer soil temperature. This technique is especially useful for normalizing microwave brightness temperatures at longer wavelengths for soil moisture retrieval algorithms, It could provide a useful tool for climate modelling, land surface processes investigations, and other energy balance applications by providing consistent and independent long term estimates of daily global surface temperature. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Owe, M (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3827-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4171 BP 86 EP 96 DI 10.1117/12.413921 PG 11 WC Agriculture, Multidisciplinary; Ecology; Geosciences, Multidisciplinary; Remote Sensing; Water Resources SC Agriculture; Environmental Sciences & Ecology; Geology; Remote Sensing; Water Resources GA BS01H UT WOS:000168322100008 ER PT S AU Foster, JL Barton, JS Chang, ATC Hall, DK AF Foster, JL Barton, JS Chang, ATC Hall, DK BE Owe, M DUrso, G Zilioli, E TI Snow crystal and land cover effects on the scattering of passive microwave radiation for algorithm development SO REMOTE SENSING FOR AGRICULTURE, ECOSYSTEMS, AND HYDROLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Remote Sensing for Agriculture, Ecosystems, and Hydrology II CY SEP 25-27, 2000 CL BARCELONA, SPAIN SP European Opt Soc, SPIE, NASA DE passive microwave; snow crystals; scattering; random orientation; algorithms; modeling AB In developing and tuning passive microwave algorithms, which are used to estimate snow extent, snow water equivalent and snow depth, much of the effort has been directed towards better accounting for the effects of snow crystal size on the microwave response, and relatively little effort has been given to the role that crystal shape or orientation plays in this regard. Modeling using a discrete dipole scattering models has shown that the assumption used in radiative transfer approaches, where snow crystals are modeled as randomly oriented spheres, is adequate to account for the transfer of microwave energy emanating from the ground and passing through a snowpack. With this in mind and by having some knowledge of the size of the particles in the snowpack as well as the snowpack density, snow depth algorithms can be designed for specific basins to assess the snow water equivalent of the basin and to thus, estimate snowmelt runoff and seasonal streamflow. Work performed on an ongoing GCIP/GEWEX experiment for watersheds in the upper Mid West and the northern Great Plains (the Roseau river basin in Minnesota/Manitoba, and the Black river basin in Wisconsin) has shown that for each of these basins, a strong correlation exists between snow depth derived from SSMI passive microwave data and snow depth measured at meteorological stations and determined from airborne gamma overflights. For instance, for the Roseau basin in mid March (Julian day 75), during the period from 1992-1998, the coefficient of determination (R-2) is a very strong 0.8975. Thus, ninety percent of the mid March snow depth variation in this basin, during these years, can be explained by the SSMI snow algorithm. Streamflow has also been correlated with maximum seasonal snow depth for these two basins as well (Figure 3). Using only SSMI-derived snow depth as the predictor or dependent variable, the R2 value for the Roseau basin was 0.715 between the basin-wide snow depth on March 15 and ensuing streamflow for the month of April. When there is a high degree of assurance that the satellite-derived estimates are reliable (the algorithms produce results which reflect the streamflow - hydrographs), they can then be used to generate input to hydrologic models. C1 NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Lab Hydrospher Proc, Greenbelt, MD 20771 USA. RP Foster, JL (reprint author), NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Lab Hydrospher Proc, Code 974, Greenbelt, MD 20771 USA. RI Hall, Dorothy/D-5562-2012 NR 17 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3827-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4171 BP 149 EP 155 DI 10.1117/12.413927 PG 7 WC Agriculture, Multidisciplinary; Ecology; Geosciences, Multidisciplinary; Remote Sensing; Water Resources SC Agriculture; Environmental Sciences & Ecology; Geology; Remote Sensing; Water Resources GA BS01H UT WOS:000168322100014 ER PT S AU Woods, DC Osborn, MT AF Woods, DC Osborn, MT BE Russell, JE Schafer, K LadoBordowsky, O TI Twenty six years of lidar monitoring of the northern mid-latitude stratospheric aerosol SO REMOTE SENSING OF CLOUDS AND THE ATMOSPHERE V SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Remote Sensing of Clouds and the Atmosphere V CY SEP 26-28, 2000 CL BARCELONA, SPAIN SP European Opt Soc, SPIE, NASA DE lidar; aerosols; backscattering; volcanic eruption ID PINATUBO; ERUPTION; CLOUD AB Aerosols in the upper troposphere and lower stratosphere have been monitored continuously during the past 26 years by a ground-based lidar system at the NASA Langley Research Center in Hampton, Virginia. The measurements were started in 1974 to support NASA's on-going atmospheric research programs, and have produced one of the world's longest continuous lidar records on northern midlatitude aerosols. The 26-year record spans periods during which the stratospheric aerosol loading was greatly enhanced by highly explosive volcanic eruptions including, Fuego in 1974, El Chichon in 1982, and Mt. Pinatubo in 1991, each of which injected enormous quantities of aerosols and gases into the stratosphere. These lidar observations of volcanic aerosol plumes in the stratosphere over long time periods have provided insight into their potential impact on global climate and other atmospheric processes. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3824-3 J9 PROC SPIE PY 2001 VL 4168 BP 249 EP 255 DI 10.1117/12.413871 PG 7 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Remote Sensing SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Remote Sensing GA BR99X UT WOS:000168299600027 ER PT S AU Neil, DO Gordley, LL Marshall, BT Sachse, GW AF Neil, DO Gordley, LL Marshall, BT Sachse, GW BE Russell, JE Schafer, K LadoBordowsky, O TI Tropospheric carbon monoxide measurements from geostationary orbit SO REMOTE SENSING OF CLOUDS AND THE ATMOSPHERE V SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Remote Sensing of Clouds and the Atmosphere V CY SEP 26-28, 2000 CL BARCELONA, SPAIN SP European Opt Soc, SPIE, NASA DE atmospheric chemistry; tropospheric chemistry; carbon monoxide; geostationary; remote sensing; pollution; air quality; GeoTRACE; calibration ID OZONE RETRIEVAL; PERFORMANCE; INSTRUMENT; CALIBRATION; BAND AB Remote sensing of atmospheric trace gases from geostationary orbit has unique scientific value and unique measurement interpretation advantages. This paper describes a proposed measurement method and analysis strategy for inferring CO concentration in the troposphere. Gas filter correlation radiometry is found to be very well suited for remote sensing using full globe images from geostationary orbit. Strengths of the gas correlation technique include measurement efficiency, effective high spectral resolution, excellent spectral calibration, manageable data rate, and measurements over the full spectral bandpass simultaneously. Unlike previous gas filer correlation radiometer systems, the design presented here enables simultaneous analysis for surface temperature, surface emissivity, atmospheric water vapor, atmospheric temperature gradient, and cloud contamination. The concurrent determination of these quantities is essential for accurate CO retrievals under clear-sky conditions for a variety of atmospheric states and surface properties. The paper discusses the measurement requirements, modeled performance, calibration approach, and measurement enhancements due to the geostationary nature of the observations. We suggest the utility of such measurements to identify source regions and long range transport, and to provide context for more localized measurement and modeling studies. This work is a summary of CO measurement capability proposed for GeoTRACE (Geostationary Observatory for Tropospheric Air Chemistry). C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP NASA, Langley Res Ctr, MS401B, Hampton, VA 23681 USA. EM d.o.neil@larc.nasa.gov NR 17 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3824-3 J9 PROC SPIE PY 2001 VL 4168 BP 265 EP 273 DI 10.1117/12.413873 PG 9 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Remote Sensing SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Remote Sensing GA BR99X UT WOS:000168299600029 ER PT J AU Choudhury, BJ AF Choudhury, BJ TI Estimating gross photosynthesis using satellite and ancillary data: Approach and preliminary results SO REMOTE SENSING OF ENVIRONMENT LA English DT Review ID RADIATION-USE EFFICIENCY; LEAF NITROGEN DISTRIBUTION; HUBBARD BROOK ECOSYSTEM; GLOBAL SOLAR-RADIATION; WATER-USE EFFICIENCY; ACTIVE RADIATION; CARBON-DIOXIDE; CANOPY PHOTOSYNTHESIS; DIFFUSE-RADIATION; DECIDUOUS FOREST AB Observations by space-borne sensors can provide photosynthetically active radiation (PAR) intercepted by a canopy (IPAR), which, together with radiation zee efficiency (RUE), can be used to estimate carbon assimilation by terrestrial plant communities. Evaluation of biological and environmental factors determining variability of RUE for daily total gross photosynthesis within and among species suggests a biophysically based approach for estimating daily total grass photosynthesis using satellite and ancillary data. Calculations have been done using leaf photosynthesis and canopy characteristics derived from field measure ments for six cultivated herbaceous and 12 uncultivated (herbaceous and needle leaf and broadleaf woody) species, and mixed species stands of temperate deciduous forest and tropical moist and dry forests. These data are for 65 canopies, divided about equally between cultivated and uncultivated species, and the leaf area index varies between 0.6 and 9.5. A model for instantaneous canopy photosynthesis, considering sunlit and shaded leaves, variation of maximum rate of leaf photosynthesis within the canopy, and a solution of the radiative transfer equation for propagation of direct and diffuse PAR, is numerically integrated in space (angular variation of radiances and depth within the canopy) and time (diurnal variation) to obtain daily total gross photosynthesis and IPAR for varied incident irradiances. The results show that the maximum rate of leaf photosynthesis and magnitudes of direct and diffuse irradiance incident on the canopy are the major factors determining RUE for unstressed conditions. Also, while woody species on the average have lower RUE, they are found to utilize diffuse radiation more efficiently them cultivated species. Comparison of calculated RUE with observations for 10 cultivated species in varied environment gave differences of -23% to +11% for individual species, but aggregately they have almost equal coefficient of variation (similar to 25%) and their averages differ by -6% (underestimation), Monthly and annual gross photosynthesis determined using satellite and ancillary data are obtained for rainforest (in Brazil), boreal forest (in Canada), and cropland (in the United States). Annual photosynthesis calculated using satellite data for the three biomes differed from, that determined from field measurements by -29% to +15%, averaging to +6%. The above error estimates for RUE and photosynthesis are obtained without calibrating any model parameter. (C)2001 Published by Elsevier Science Ireland Ltd. C1 NASA, Goddard Space Flight Ctr, Lab Hydrospher Proc, Hydrol Sci Branch, Greenbelt, MD 20771 USA. RP Choudhury, BJ (reprint author), NASA, Goddard Space Flight Ctr, Lab Hydrospher Proc, Hydrol Sci Branch, Code 974, Greenbelt, MD 20771 USA. NR 142 TC 57 Z9 66 U1 0 U2 12 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD JAN PY 2001 VL 75 IS 1 BP 1 EP 21 DI 10.1016/S0034-4257(00)00151-6 PG 21 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 387VF UT WOS:000166142000001 ER PT J AU Kimball, JS McDonald, KC Keyser, AR Frolking, S Running, SW AF Kimball, JS McDonald, KC Keyser, AR Frolking, S Running, SW TI Application of the NASA scatterometer (NSCAT) for determining the daily frozen and nonfrozen landscape of Alaska SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID ENVIRONMENTAL-CONDITIONS; MICROWAVE SIGNATURES; BOREAL FOREST; IMAGING RADAR; ERS-1 SAR; THAW; ECOSYSTEMS; BALANCE; TERRAIN; SYSTEM AB The seasonal transition of the land surface between frozen and nonfrozen conditions affects a number of terrestrial processes that cycle between wintertime dormant and summertime active states. The relatively short (2.14 cm) K-u-band of the space-borne NASA scatterometer (NSCAT) is sensitive to changes in dielectric properties, associated with large-scale shifts in the relative abundance and phase (frozen or thawed) of canopy and surface water. We used a temporal change detection analysis of NSCAT daily radar backscatter measurements to classify surface freeze/thaw state across a 1.4 million km(2) region of Alaska from January to June 1997. In the spring, radar backscatter measurements showed pronounced decreases (1.6-4.9 dB) relative to reference frozen state conditions, which corresponded with sustained maximum daily air temperature measurements above 0.0 degreesC and total decreases in measured snow depths from 28% to 61% of seasonal maximum values. We classified the daily frozen and nonfrozen area for the region based on the sign (+/-) of the radar backscatter temporal difference relative to frozen and nonfrozen reference conditions. These results compared favorably (e.g., r(2) = 0.881; p less than or equal to 0.0001) with frozen area estimates derived from the regional weather station network. NSCAT-derived estimates of the timing and spatial variation in regional thaw during spring were also generally consistent with seasonal increases in river discharge for five major Alaska basins. The NSCAT sensor appears to be responsive to changes in dielectric properties associated with surface freeze/thaw transitions over broad boreal and arctic landscapes. Further study involving longer time-series information, alternative radar wavelengths, and finer spatial scales is needed, however, to resolve the various components (i.e., soil, vegetation, snow) of the regional radar freeze/thaw signature for improved monitoring of the circumpolar high latitudes. (C) Elsevier Science Inc., 2001. C1 Univ Montana, Flathead Lake Biol Stn, Polson, MT 59860 USA. Univ Montana, Sch Forestry, NTSG, Missoula, MT 59812 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ New Hampshire, Durham, NH 03824 USA. RP Kimball, JS (reprint author), Univ Montana, Flathead Lake Biol Stn, 311 Bio Stn Lane, Polson, MT 59860 USA. NR 40 TC 55 Z9 62 U1 1 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD JAN PY 2001 VL 75 IS 1 BP 113 EP 126 DI 10.1016/S0034-4257(00)00160-7 PG 14 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 387VF UT WOS:000166142000010 ER PT B AU Roberts, MJ AF Roberts, MJ BE Thompson, DO Chimenti, DE TI Temporal microwave nondestructive evaluation for material characterization, void and moisture detection in layered structures SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOLS 20A AND 20B SE REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION LA English DT Proceedings Paper CT 27th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 16-20, 2000 CL IOWA STATE UNIV, AMES, IA SP Amer Soc Nondestruct Testing, FAA, Inst Phys Sci & Technol, NASA, Natl Sci Fdn HO IOWA STATE UNIV DE microwaves; voids; moisture; delamination ID COMPOSITES AB Temporal microwave contact reflection measurements are performed using a vector network analyzer for delamination, void and moisture detection. Specific layered structures are measured and numerically simulated: a plexiglas panel and transparent glass piece, and a generic composite containing three holes and transparent glass piece. Each structure either has water placed between its layers and / or in contained voids or is kept dry. Numerical comparisons are made with reflection measurements. C1 NASA, Langley Res Ctr, NDE Sci Branch, Hampton, VA 23681 USA. RP Roberts, MJ (reprint author), NASA, Langley Res Ctr, NDE Sci Branch, Hampton, VA 23681 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA BN 1-56396-988-2 J9 REV PROG Q PY 2001 VL 557 BP 414 EP 421 PN A&B PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Optics; Physics, Applied SC Acoustics; Engineering; Materials Science; Optics; Physics GA BT38Q UT WOS:000172833800052 ER PT B AU Yost, WT Cantrell, JH Na, JK AF Yost, WT Cantrell, JH Na, JK BE Thompson, DO Chimenti, DE TI Nonlinear ultrasonic pulsed measurements and applications to metal processing and fatigue SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOLS 20A AND 20B SE REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION LA English DT Proceedings Paper CT 27th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 16-20, 2000 CL IOWA STATE UNIV, AMES, IA SP Amer Soc Nondestruct Testing, FAA, Inst Phys Sci & Technol, NASA, Natl Sci Fdn HO IOWA STATE UNIV ID HARMONIC-GENERATION AB Nonlinear ultrasonics research at NASA-Langley Research Center emphasizes development of experimental techniques and modeling, with applications to metal fatigue and metals processing. This review work includes a summary of results from our recent efforts in technique refinements modeling of fatigue related microstructure contributions, and measurements on fatigued turbine blades. Also presented are data on 17-4PH and 410-Cb stainless steels. The results are in good agreement with the models. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Yost, WT (reprint author), NASA, Langley Res Ctr, Mail Stop 231, Hampton, VA 23681 USA. NR 15 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA BN 1-56396-988-2 J9 REV PROG Q PY 2001 VL 557 BP 1268 EP 1275 PN A&B PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Optics; Physics, Applied SC Acoustics; Engineering; Materials Science; Optics; Physics GA BT38Q UT WOS:000172833800165 ER PT J AU Pinelli, TE AF Pinelli, TE TI Distinguishing engineers from scientists - The case for an engineering knowledge community SO SCIENCE & TECHNOLOGY LIBRARIES LA English DT Article DE engineers; scientists; knowledge community; library services; management; knowledge diffusion; innovation ID INFORMATION NEEDS; TECHNOLOGY AB This article makes the case for an engineering knowledge community. We begin by discussing the differences between science and technology. We next discuss the similarities and differences between engineers and scientists. Next, we analyze previous research into the information use behaviors of engineers. Finally, using the research results from the NASA/DoD Aerospace Knowledge Diffusion Research Project, we compare and contrast aerospace engineers and scientists as a means of developing similarities and differences between engineers and scientists in terms of their information-seeking behavior. The goal of this article is to demonstrate that engineers are not scientists and that knowledge production and use differ in engineering and science. We believe that the current model used to explain information-seeking behavior assumes no difference between the information-seeking of engineers and scientists. The distinctions between engineering and science, engineers and scientists and the information-seeking behaviors of engineers and scientists have multiple implications for providing information services, knowledge management, and diffusing knowledge. The message to libraries is "know thy customer". C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Pinelli, TE (reprint author), NASA, Langley Res Ctr, Mail Stop 400, Hampton, VA 23681 USA. NR 68 TC 2 Z9 2 U1 1 U2 7 PU HAWORTH PRESS INC PI BINGHAMTON PA 10 ALICE ST, BINGHAMTON, NY 13904-1580 USA SN 0194-262X J9 SCI TECH LIBR JI Sci. Technol. Libr. PY 2001 VL 21 IS 3-4 BP 131 EP 163 DI 10.1300/J122v21n03_09 PG 33 GA 731AR UT WOS:000185862800009 ER PT B AU Stapelfeldt, K Padgett, D AF Stapelfeldt, K Padgett, D BE Wootten, A TI Comparing Hubble Space Telescope and millimeter interferometer images of young stellar object disks SO SCIENCE WITH THE ATACAMA LARGE MILLIMETER ARRAY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Science with the Atacama Large Millimeter Array CY OCT 06-08, 1999 CL CARNEGIE INST WASHINGTON, WASHINGTON, D.C. SP Assoc Univ Inc, Natl Radio Astron Observ HO CARNEGIE INST WASHINGTON ID CIRCUMSTELLAR DISKS; CIRCUMBINARY DISK; ORION NEBULA; UY AURIGAE; GG TAURI; BINARY; MASS; RING AB With angular sizes of just a few arcseconds, circumstellar disks in nearby star formation regions require subarcsecond imaging to study in detail. The best-resolved disk images currently available are those made in optical and near-infrared reflected light using the Hubble Space Telescope. Millimeterwave imaging provides crucial comparative information on these disks, but at somewhat lower spatial resolution. We illustrate this through a comparison of OVRO Millimeter Array maps and HST images for two edge-on young disks, IRAS 04302+2247 and HH 30. Dense, rotating molecular gas structures are found along their visible dust lanes. Somewhat unexpectedly, the scattered light and millimeterwave data lead us to derive similar values for the size and mass of these disks. By providing millimeter maps with resolutions equal to or exceeding that of HST, ALMA will increase nearly one hundredfold the number of young disks that can be imaged at 10 AU resolution, thereby enabling huge gains in our understanding of how planetary systems form and evolve. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Stapelfeldt, K (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RI Stapelfeldt, Karl/D-2721-2012 NR 24 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-072-2 J9 ASTR SOC P PY 2001 VL 235 BP 163 EP 170 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU31Q UT WOS:000175670700024 ER PT B AU Yorke, HW Richling, S AF Yorke, HW Richling, S BE Wootten, A TI Modeling high spatial resolution images of protostellar disks SO SCIENCE WITH THE ATACAMA LARGE MILLIMETER ARRAY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Science with the Atacama Large Millimeter Array CY OCT 06-08, 1999 CL CARNEGIE INST WASHINGTON, WASHINGTON, D.C. SP Assoc Univ Inc, Natl Radio Astron Observ HO CARNEGIE INST WASHINGTON ID PHOTOEVAPORATION C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yorke, HW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-072-2 J9 ASTR SOC P PY 2001 VL 235 BP 187 EP 190 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU31Q UT WOS:000175670700029 ER PT B AU Leisawitz, D Mather, JC Langer, W Moseley, SH Mundy, LG Swain, M Yorke, HW Zhang, X AF Leisawitz, D Mather, JC Langer, W Moseley, SH Mundy, LG Swain, M Yorke, HW Zhang, X BE Wootten, A TI Far-Infrared/Submillimeter interferometry: A space frontier SO SCIENCE WITH THE ATACAMA LARGE MILLIMETER ARRAY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Science with the Atacama Large Millimeter Array CY OCT 06-08, 1999 CL CARNEGIE INST WASHINGTON, WASHINGTON, D.C. SP Assoc Univ Inc, Natl Radio Astron Observ HO CARNEGIE INST WASHINGTON ID BACKGROUND EXPERIMENT SEARCH; FIRAS AB Space-based Far IR/submillimeter (FIR/SMM) interferometry is necessary to answer fundamental cosmological questions concerning the development of structure in the Universe and could also be used to probe nearby objects such as protoplanetary disks and star forming regions in unprecedented detail. We describe concepts for the Space Infrared Interferometric Telescope (SPIRIT) and the Submillimeter Probe of the Evolution of Cosmic Structure (SPECS). Both are imaging and spectral Michelson interferometers operating in the wavelength range similar to 40 - 500mum. SPIRIT, which could be launched in a decade, is built on a deployable boom and has a maximum baseline of - 30 m, providing arcsecond resolution in the far-IR. SPECS uses formation flying to attain baseline lengths up to similar to 1 km, and thus angular resolution comparable to that of the Hubble Space Telescope (HST), the Next Generation Space Telescope (NGST), and the Atacama Large Millimeter Array (ALMA). SPIRIT and SPECS would provide access to many important cooling and diagnostic spectral lines and to the bulk of the thermal emission from dust, and make observations complementary to those obtained with ALMA and NGST. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Leisawitz, D (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Moseley, Harvey/D-5069-2012 NR 10 TC 0 Z9 0 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-072-2 J9 ASTR SOC P PY 2001 VL 235 BP 237 EP 240 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU31Q UT WOS:000175670700037 ER PT J AU Bennett, CL Hinshaw, GF Page, L AF Bennett, CL Hinshaw, GF Page, L TI A cosmic cartographer SO SCIENTIFIC AMERICAN LA English DT Article C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Bennett, CL (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. OI Page, Lyman/0000-0002-9828-3525 NR 0 TC 1 Z9 1 U1 0 U2 1 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 USA SN 0036-8733 J9 SCI AM JI Sci.Am. PD JAN PY 2001 VL 284 IS 1 BP 44 EP 45 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 384TP UT WOS:000165962000029 PM 11132421 ER PT B AU Boggs, CH AF Boggs, CH BE Melvin, EF Parrish, JK TI Deterring albatrosses from contacting baits during swordfish longline sets SO SEABIRD BYCATCH: TRENDS,ROADBLOCKS AND SOLUTIONS SE UNIVERSITY OF ALASKA SEA GRANT COLLEGE PROGRAM REPORT LA English DT Proceedings Paper CT 26th Annual Meeting of the Pacific-Seabird-Group CY FEB 26-27, 1999 CL BLAINE, WA SP Pacific Seabird Grp, US Fish & Wildlife Serv, Portland Migrator Bird Off ID CATCH RATES; FISHERY AB The effectiveness of albatross deterrent techniques was examined during line setting operations in the Hawaii-based longline fishery for swordfish (Xiphias gladius). Methods tested were bird scaring streamer lines, weights added to baits, and camouflaging bait with food coloring. Observations were made on ca. 66 baited branch lines deployed on 96 occasions. Baits dyed blue and baits with added weight both reduced the number of contacts between baits and Black-footed (Phoebastria nigripes) and Laysan (P. immutabilis) Albatrosses by about 90%. Streamer lines reduced contacts between baits and albatrosses by about 70%. C1 NOAA, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. RP Boggs, CH (reprint author), NOAA, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. NR 15 TC 22 Z9 25 U1 0 U2 1 PU UNIV ALASKA SEA GRANT PI FAIRBANKS PA POB 755040, 205 ONEILL BLDG, FAIRBANKS, AK 99775 USA BN 1-56612-066-7 J9 UASGCP REP PY 2001 VL 2001 IS 1 BP 79 EP 94 PG 16 WC Zoology SC Zoology GA BS49J UT WOS:000170086700007 ER PT B AU Cousins, KL AF Cousins, KL BE Melvin, EF Parrish, JK TI The Black-footed Albatross population biology workshop: A step to understanding the impacts of longline fishing on seabird populations SO SEABIRD BYCATCH: TRENDS,ROADBLOCKS AND SOLUTIONS SE UNIVERSITY OF ALASKA SEA GRANT COLLEGE PROGRAM REPORT LA English DT Proceedings Paper CT 26th Annual Meeting of the Pacific-Seabird-Group CY FEB 26-27, 1999 CL BLAINE, WA SP Pacific Seabird Grp, US Fish & Wildlife Serv, Portland Migrator Bird Off AB Experts in seabird ecology, fisheries management, and population modeling participated in a three-day workshop (October 8-10, 1998) at the Western Pacific Regional Fishery Management Council (WPRFMC) offices in Honolulu to investigate the population dynamics of the Black-footed Albatross (Phoebastria nigripes). The workshop's primary goal was to characterize the population biology of the Black-footed Albatross and evaluate its resilience to the effects of mortality due to longline fishery interactions. Worldwide there are 61,866 and 558,415 breeding pairs of Black-footed and Laysan (P. immutabilis) Albatrosses, respectively, and both species are caught in approximately equal numbers during longline fishing. This suggests that the Black-footed Albatross population may be more seriously affected. The Black-footed Albatross population suffers different combinations of both anthropogenic and natural mortalities, in common with many seabird populations. Thus, a series of simulations were conducted to investigate how population removals added onto baseline mortality would affect the sustainable population growth rates. Also, analyses generated from the bird-banding data sets found that juvenile Black-footed Albatrosses were caught on longline more frequently than adults. Simulated experiments also investigated how differences in juvenile and adult removals would affect the Black-footed Albatross population dynamics. The findings showed that over the long term, a chronic mortality such as longline fishing resulted in slow decline of species population size irrespective of uncertainties associated with the estimated parameters. Workshop participants generated seven recommendations for consideration by the WPRFMC, including the improvement and standardization of data collection and the completion of analyses as studies progress. C1 NOAA, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. RP Cousins, KL (reprint author), NOAA, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. NR 15 TC 2 Z9 3 U1 0 U2 0 PU UNIV ALASKA SEA GRANT PI FAIRBANKS PA POB 755040, 205 ONEILL BLDG, FAIRBANKS, AK 99775 USA BN 1-56612-066-7 J9 UASGCP REP PY 2001 VL 2001 IS 1 BP 95 EP 114 PG 20 WC Zoology SC Zoology GA BS49J UT WOS:000170086700008 ER PT S AU Hoover, RB Rozanov, AY AF Hoover, RB Rozanov, AY BE Kingsley, SA Bhathal, R TI Evidence for biomarkers and microfossils in ancient rocks and meteorites SO SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE (SETI) IN THE OPTICAL SPECTRUM III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on the Search for Extraterrestrial Intelligence (SETI) in the Optical Spectrum III CY JAN 22-24, 2001 CL SAN JOSE, CA SP SPIE DE biomarkers; meteorites; carbonaceous chondrites; astrobiology; extremophiles; microfossils ID MASSIVE SULFIDE DEPOSIT; EARLY SOLAR-SYSTEM; MURCHISON METEORITE; CARBONACEOUS CHONDRITES; AMINO-ACIDS; ORGANIC-MATTER; HYDROCARBONS; EARTH; SEDIMENTS; BACTERIA AB We review prior studies of chemical and morphological biomarkers in ancient rocks and meteorites and present recently obtained ESEM images of microfossils and nanofossils in-situ in freshly fractured surfaces of Nogoya and pristine samples of Murchison as farther evidence of indigenous microfossils in meteorites. C1 NASA, George C Marshall Space Flight Ctr, Astrobiol Grp, Dept Space Sci, Huntsville, AL 35812 USA. RP Hoover, RB (reprint author), NASA, George C Marshall Space Flight Ctr, Astrobiol Grp, Dept Space Sci, SD-50, Huntsville, AL 35812 USA. NR 125 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3951-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4273 BP 15 EP 32 DI 10.1117/12.435380 PG 18 WC Optics SC Optics GA BT28H UT WOS:000172533100003 ER PT S AU Stride, SL AF Stride, SL BE Kingsley, SA Bhathal, R TI Instrument technologies for the detection of extraterrestrial interstellar robotic probes SO SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE (SETI) IN THE OPTICAL SPECTRUM III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on the Search for Extraterrestrial Intelligence (SETI) in the Optical Spectrum III CY JAN 22-24, 2001 CL SAN JOSE, CA SP SPIE DE SETI; OSETI; interstellar probes; instruments; sensors; embedded computing; detection platforms AB In the continuing endeavor to detect evidence of ETI (Extraterrestrial Intelligence) in the solar neighborhood, instrument technologies now exist that allow the formation of a scientific method to carry out a search for interstellar robotic probes of possible extraterrestrial origin. The range of currently observable probe features/manifestations will be shown and how they influence search space, instrument selection and deployment. Autonomous instrument platforms (i.e. robotic observatories) to search for anomalous energy signatures can be designed and assembled using Commercial off-the-shelf (COTS) hardware and software. The COTS approach to observatory design provides an economical, flexible and robust path toward collecting reliable data. The present variety of COTS instruments permits the necessary observational sensitivity, bandwidth and embedded processing speed to establish a nearby robotic probe detection envelope. A survey of these instrument technologies will be presented and how they can be applied to the challenge of collecting enough scientific data on anomalous observational phenomena to determine whether or not a robotic probe was detected. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Stride, SL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3951-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4273 BP 178 EP 189 DI 10.1117/12.435372 PG 12 WC Optics SC Optics GA BT28H UT WOS:000172533100020 ER PT S AU Hemmati, H AF Hemmati, H BE Kingsley, SA Bhathal, R TI Overview of laser communications research at JPL SO SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE (SETI) IN THE OPTICAL SPECTRUM III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on the Search for Extraterrestrial Intelligence (SETI) in the Optical Spectrum III CY JAN 22-24, 2001 CL SAN JOSE, CA SP SPIE DE optical communications; laser communications; photon bucket ID DESIGN AB Future NASA arid commercial space missions will require communications terminals to provides higher data rate with lower mass and power. Optical communications is a rapidly developing technology in response to this demand. Component and system technologies for both communications from Earth orbit and deep space is under development. This includes both ends of the link: the flight terminal and the ground receiver. Data-rates for Earth-orbit to ground or earth-orbit to earth orbit (e.g. LEO-to-GEO) are on the order of Gig-bits per second (Gbps). A 1-meter diameter ground receiver would be adequate at this range. The deep-space communication data-rates are on the order of 10's of kbps to 100's of kbps. Large receiver diameters (ideally greater than 10 m) will be required for most deep-space missions. The ground receiver will be a non-imaging system to efficiently collect signal photons. Thus, surface quality could be inferior to those used for astronomy. However, surface quality has to be high enough quality such that the received beams may be focused to a small diameter detector (a few hundred microns to a few millimeters in active region depending on the pulse-width of the signal and requirements for ranging). NASA is currently building a 1-m R&D telescope laboratory at its Table Mountain Facility in southern California to answer key implementation questions of this technology. The telescope is designed with fast tracking capability and will act as a testbed for development of ground acquisition, tracking and communications strategies applicable to future operational stations. Establishment of requirements and analysis to predict the performance of large diameter "photon bucket" telescope is continuing. These and other programs currently under development are described below. C1 CALTECH, Jet Prop Lab, Opt Commun Grp, Pasadena, CA 91109 USA. RP Hemmati, H (reprint author), CALTECH, Jet Prop Lab, Opt Commun Grp, 4800 Oak Grove Dr,MS 161-135, Pasadena, CA 91109 USA. NR 6 TC 2 Z9 2 U1 1 U2 6 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3951-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4273 BP 190 EP 193 DI 10.1117/12.435371 PG 4 WC Optics SC Optics GA BT28H UT WOS:000172533100021 ER PT S AU Baumgartner, ET Aghazarian, H Trebi-Ollennu, A AF Baumgartner, ET Aghazarian, H Trebi-Ollennu, A BE McKee, GT Schenker, PS TI Rover localization results for the FIDO Rover SO SENSOR FUSION AND DECENTRALIZED CONTROL IN ROBOTIC SYSTEMS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensor Fusion and Decentralized Control in Robotic Systems IV Conference CY OCT 28-29, 2001 CL NEWTON, MA SP SPIE DE rover localization; rover state estimation; Kalman filter; inertial measurement units ID MOBILE AB This paper describes the development of a two-tier state estimation approach for NASA/JPL's FIDO Rover that utilizes wheel odometry, inertial measurement sensors, and a sun sensor to generate accurate estimates of the rover's position and attitude throughout a rover traverse. The state estimation approach makes use of a linear Kalman filter to estimate the rate sensor bias terms associated with the inertial measurement sensors and then uses these estimated rate sensor bias terms to compute the attitude of the rover during a traverse. The estimated attitude terms are then combined with the wheel odometry to determine the rover's position and attitude through an extended Kalman filter approach. Finally, the absolute heading of the vehicle is determined via a sun sensor which is then utilized to initialize the rover's heading prior to the next planning cycle for the rover's operations. This paper describes the formulation, implementation, and results associated with the two-tier state estimation approach for the FIDO rover. C1 CALTECH, Jet Prop Lab, Sci & Technol Dev Sect, Pasadena, CA 91109 USA. RP Baumgartner, ET (reprint author), CALTECH, Jet Prop Lab, Sci & Technol Dev Sect, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 15 TC 11 Z9 12 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4299-2 J9 P SOC PHOTO-OPT INS PY 2001 VL 4571 BP 34 EP 44 DI 10.1117/12.444167 PG 11 WC Engineering, Electrical & Electronic; Robotics; Optics SC Engineering; Robotics; Optics GA BT92W UT WOS:000174463400004 ER PT S AU Pirjanian, P Huntsberger, TL Schenker, PS AF Pirjanian, P Huntsberger, TL Schenker, PS BE McKee, GT Schenker, PS TI Development of CAMPOUT and its further applications to planetary rover operations: a multi-robot control architecture SO SENSOR FUSION AND DECENTRALIZED CONTROL IN ROBOTIC SYSTEMS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensor Fusion and Decentralized Control in Robotic Systems IV Conference CY OCT 28-29, 2001 CL NEWTON, MA SP SPIE DE control architecture; multi-robot systems; tight coordination; planetary rover operations ID NAVIGATION AB In this paper, we describe an architecture for the development of autonomy software for multi-robot distributed control and collective estimation. CAMPOUT, the Control Architecture for Multi-Robot Planetary OUTposts, provides communication facilities for sharing of state information across robots and it uses a behavior network for representation and execution of group activities as well as the activities of a single robot. In our research, we have shown that CAMPOUT provides a level of abstraction that enables us to develop multi-robot software in a manner much similar to what we use for single robot software development. We showcase the main architectural components by describing two multi-robot tasks for planetary construction and collective cliff-descent. For both tasks, we show how behavior networks can be used to describe group activities and how publish/subscribe and other communication mechanisms can be used to share state information across multiple robots. C1 CALTECH, Jet Prop Lab, Planetary Robot Lab, Pasadena, CA 91109 USA. RP Pirjanian, P (reprint author), CALTECH, Jet Prop Lab, Planetary Robot Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 19 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4299-2 J9 P SOC PHOTO-OPT INS PY 2001 VL 4571 BP 108 EP 119 DI 10.1117/12.444151 PG 12 WC Engineering, Electrical & Electronic; Robotics; Optics SC Engineering; Robotics; Optics GA BT92W UT WOS:000174463400011 ER PT S AU Hancock, BR Cunningham, TJ McCarty, K Yang, G Wrigley, C Ringold, PG Stirbl, RC Pain, B AF Hancock, BR Cunningham, TJ McCarty, K Yang, G Wrigley, C Ringold, PG Stirbl, RC Pain, B BE Blouke, MM Canosa, J Sampat, N TI Multi-megarad (Si) radiation tolerant integrated CMOS imager SO SENSORS AND CAMERA SYSTEMS FOR SCIENTIFIC, INDUSTRIAL, AND DIGITAL PHOTOGRAPHY APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensors and Camera Systems for Scientific, Industrial, and Digital Photography Applications CY JAN 24-26, 2000 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, SPIE DE CMOS imager; radiation-hardness; visible detector; dark current; LOCOS; interface ID SENSORS AB The paper describes the design, operation, and performance of integrated CMOS imagers that withstand multi-megarad(Si) total dose of ionizing radiation. It reports test results from two imagers - one with on-chip integrated timing and control, and the other with a variety of pixel structures for parametrically investigating the effects of radiation on imager performance. The CMOS imager has been shown to respond only to ionizing radiation, and is able to withstand high proton fluence. Minimal change in imager performance is observed after being subjected to a proton fluence of 1.2x10(12) protons/cm(2). The imager also exhibits minimal change in optical response after being dosed with 1.5 Megarad(Si). The radiation-induced dark current is small (similar to few pA/cm(2)/krad), and is well-behaved over the entire dose range. No change in operating bias is needed either for operating the imager at low-temperature or after irradiation. The parametric test chip indicates that the LOCOS region plays a significant role in determining the total-dose-hardness of the pixel. Based on test results, most promising pixel structures for imaging under high radiation environments have been identified. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Hancock, BR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. NR 12 TC 18 Z9 18 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3984-3 J9 P SOC PHOTO-OPT INS PY 2001 VL 4306 BP 147 EP 155 DI 10.1117/12.426989 PG 3 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BS57Y UT WOS:000170428700017 ER PT S AU Neeck, SP Flaming, GM Adams, WJ Smith, EA AF Neeck, SP Flaming, GM Adams, WJ Smith, EA BE Fujisada, H Lurie, JB Weber, K TI Global Precipitation Measurement (GPM) SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA AB The National Aeronautics and Space Administration (NASA) is studying options for future space-based missions for the EOS Follow-on Era (post 2003), building upon the measurements made by Pre-EOS and EOS First Series Missions. One mission under consideration is the Global Precipitation Measurement (GPM), a cooperative venture of NASA, Japan, and other international partners. GPM will capitalize on the experience of the highly successful Tropical Rainfall Measurement Mission (TRMM). It's goal is to extend the measurement of rainfall to high latitudes with high temporal frequency, providing a global data set every three hours. A reference concept has been developed consisting of an improved TRMM-like primary satellite with precipitation radar and microwave radiometer to make detailed and accurate estimates of the precipitation structure and a constellation of small satellites flying compact microwave radiometers to provide the required temporal sampling of highly variable precipitation systems. Considering that DMSP spacecraft equipped with SSMIS microwave radiometers, successor NPOESS spacecraft equipped with CMIS microwave radiometers, and other relevant international systems are expected to be in operation during the timeframe of the reference concept, the total number of small satellites required to complete the constellation will be reduced. A no minal plan is to begin implementation in FY'03 with launches in 2007. NASA is presently engaged in advanced mission studies and advanced instrument technology development related to the mission. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Neeck, SP (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 11 EP 15 DI 10.1117/12.450651 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200002 ER PT S AU Storey, JC AF Storey, JC BE Fujisada, H Lurie, JB Weber, K TI Landsat 7 on-orbit modulation transfer function estimation SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA DE landsat 7; ETM; MTF; point spread function AB The Landsat 7 spacecraft and its Enhanced Thematic Mapper Plus (ETM+) were launched on April 15, 1999. Pre-launch modeling of the ETM+ optical system predicted that modulation transfer function (MTF) performance would change on-orbit. A method was developed to monitor the along-scan MTF performance of the ETM+ sensor system using on-orbit data of the Lake Pontchartrain Causeway in Louisiana. ETM+ image scan lines crossing the bridge were treated as multiple measurements of the target taken at varying sampling phases. These line measurements were interleaved to construct an over-sampled target profile for each ETM+ scan direction. Corresponding profiles were simulated using analytical models of the bridge and of the ETM+ system transfer function. Model parameters were adjusted to achieve the best fit between the simulated profiles and the image measurements. The ETM+ modulation at the Nyquist frequency and the full width at half maximum of the point spread function were computed from the best-fit system transfer function model. Trending these parameters over time revealed apparent MTF performance degradation, observed mainly in the 15-meter resolution ETM+ panchromatic band. This confirmed the pre-launch model prediction that the panchromatic band was the most sensitive to changes in ETM+ optical performance. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Storey, JC (reprint author), NASA, Goddard Space Flight Ctr, Code 923, Greenbelt, MD 20771 USA. NR 11 TC 20 Z9 21 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 50 EP 61 DI 10.1117/12.450647 PG 12 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200006 ER PT S AU Shiue, JC AF Shiue, JC BE Fujisada, H Lurie, JB Weber, K TI The Advanced Technology Microwave Sounder, a new atmospheric temperature and humidity sounder for operational polar-orbiting weather satellites SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA DE microwave radiometry; atmosphere; temperature; humidity; sounders AB The Advanced Technology Microwave Sounder (ATMS) is a new generation of microwave instrument for measuring atmospheric temperature and humidity profiles from satellites. It is being developed in the U.S. for the future operational weather satellite systems, called the National Polar-orbiting Operational Environment Satellite System (NPOESS). This paper presents some key design features of the ATMS, its essential characteristics, the expected performance, and program status. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Shiue, JC (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 2 TC 2 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 159 EP 165 DI 10.1117/12.450657 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200016 ER PT S AU Palluconi, F Tonooka, H Hook, S Abtahi, A Alley, R Thompson, T Hoover, G Zadourian, S AF Palluconi, F Tonooka, H Hook, S Abtahi, A Alley, R Thompson, T Hoover, G Zadourian, S BE Fujisada, H Lurie, JB Weber, K TI EOS ASTER thermal infrared band vicarious calibration SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA AB Calibration of the five EOS ASTER instrument emission bands (90 in pixels at surface) is being checked during the operational life of the mission using field measurements simultaneous with the image acquisition. For water targets, radiometers, temperature measuring buoys and local radiosonde atmospheric profiles are used to determine the average water surface kinetic temperature over areas roughly 3 X 3 pixels in size. The in-band surface leaving radiance is then projected through the atmosphere using the MODTRAN radiation transfer code allowing an at sensor radiance comparison. The instrument at sensor radiance is also projected to the water surface allowing a comparison in terms of water surface kinetic temperature. Over the first year of operation, the field measurement derived at sensor radiance agrees with the image derived radiance to better than plus/minus 1% for all five bands indicating both stable and accurate operation. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Palluconi, F (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 1 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 255 EP 259 DI 10.1117/12.450667 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200026 ER PT S AU Stirbl, R Pain, B Cunningham, T Hancock, B Sun, C Yang, G Heynssens, J Wrigley, C AF Stirbl, R Pain, B Cunningham, T Hancock, B Sun, C Yang, G Heynssens, J Wrigley, C BE Fujisada, H Lurie, JB Weber, K TI Advances in 2nd generation, ultra-low power CMOS active pixel sensor imagers for remote sensing, star tracking, optical comm and low-cost solar array/antenna boom deployment metrology SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA DE APS; active pixel sensor; lasercom; sun sensor; deployment monitor; "camera-on-a-chip"; star tracker ID APS AB JPL has implemented advances in CMOS APS visible sensors(1-4) well suited for the development of ultra-low power, miniature, highly integrated image sensor systems. Applications for these low cost, modular, high performance "camera-on-a-chip" sensors include: remote earth and planetary visible science cameras, wireless payload deployment monitors(5) for large mirrors, solar panels, booms and antennas, and FPAs for star trackers(6-11), sun sensors(12) and high bandwidth multi-window optical communication beacon tracker(13,14). This paper reports on the newest generation of CMOS APS dubbed the Versatile Integrated Digital Imager or VIDI APS "camera-on-a-chip". VIDI is an integrated, digital "chip-camera" with a 512 x 512 format, 12-um pixels, utilizing a single 3.3 V supply, with analog or 10-bit digital output, fabricated on a standard 0.5 um CMOS process. The chip size is 10 mm x 15.5 mm. Features include a simple, all digital "five-wire" interface, on-chip timing, control, four five-bit DACs for bias generation, and 512 column parallel ADCs. VIDI offers programmable exposure, resolution, data efficient "smart" area-of-interest windowed high speed readout, no blooming, while continuing to operate with similar to 20 mW of power in the on-state and similar to 40 uW in the "sleep" state and has a maximum data rate of 20 Mbits/sec. C1 CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. RP Stirbl, R (reprint author), CALTECH, Jet Prop Lab, NASA, 4800 Oak Grove Dr,MS-300-315, Pasadena, CA 91109 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 278 EP 287 DI 10.1117/12.450670 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200029 ER PT S AU Eisenman, A Liebe, CC Maimone, MW Schwochert, MA Willson, RG AF Eisenman, A Liebe, CC Maimone, MW Schwochert, MA Willson, RG BE Fujisada, H Lurie, JB Weber, K TI Mars exploration rover engineering cameras SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA DE Mars; Mars Exploration Rover; CCD; surface navigation; hazard avoidance; solar imaging ID SYSTEM AB The NASA Mars Exploration Rover mission will launch two scientific spacecraft to Mars in 2003. The primary goal of the mission is to obtain knowledge of ancient water and climate on the red planet. Each spacecraft will carry one rover with a mass of similar to150 kg and a design lifetime of about 90 days to the surface of Mars. The rovers are intended to travel up to 100 meters per day. The scientific payloads of the rovers will include a stereo pair of Panoramic cameras and a Microscopic Imager. The Panoramic cameras also support the engineering functions of high gain antenna pointing and navigation by solar imaging. The rovers have six additional cameras that will be used, exclusively, for engineering. All nine cameras share a common design, except for their optics. The focal plane of each camera is a 1024 x 1024-pixel frame transfer CCD. A stereo pair of Navigation cameras is mounted on a gimbal with the Panoramic camera pair. The Navigation camera pair is used for traverse planning and general imaging. Finally, one stereo pair of wide-angle Hazard Avoidance cameras will be mounted on the front (and one pair on the back) of each rover to autonomously generate range maps of the surrounding area for obstacle detection and avoidance. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Eisenman, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,M-S 198-135, Pasadena, CA 91109 USA. NR 9 TC 6 Z9 7 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 288 EP 297 DI 10.1117/12.450671 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200030 ER PT S AU Minnis, P Huang, J Doelling, DR Valero, FPJ AF Minnis, P Huang, J Doelling, DR Valero, FPJ BE Fujisada, H Lurie, JB Weber, K TI Simulation and correction of Triana viewed earth radiation budget with ERBE data SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA AB This paper describes the simulation of the earth radiation budget (ERB) as viewed by Triana and the development of correction models for converting Triana-viewed radiances in to a complete ERB. A full range of Triana views and global radiation fields are simulated using data from the Earth Radiation Budget Experiment (ERBE) and analyzed with a set of empirical correction factors specific to the Triana views. The results show that the accuracy of global correction factors to estimate ERB from Triana radiances is a function of the Triana position from Lagrange-1 (L1) or the Sun position. Spectral analysis of the global correction factor indicates that both shortwave (SW) and longwave (LW) parameters undergo seasonal and diurnal cycles that dominate the periodic fluctuations. The diurnal cycle, especially its amplitude. is also strongly dependent on the seasonal cycle. Based on these results, models are developed to correct the radiances for unviewed areas and anisotropic emission and reflection. A preliminary assessment indicates that these correction models can be applied to Triana radiances to produce the most accurate global ERB to date. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Minnis, P (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 391 EP 401 DI 10.1117/12.450681 PG 11 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200040 ER PT S AU Sorensen, IJ Sanchez, MC Priestley, KJ Mahan, JR AF Sorensen, IJ Sanchez, MC Priestley, KJ Mahan, JR BE Fujisada, H Lurie, JB Weber, K TI Optimization of CERES level 1 data products SO SENSORS, SYSTEMS AND NEXT-GENERATION SATELLITES V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Sensors, Systems, and Next-Generation Satellites V Conference CY SEP 17-20, 2001 CL TOULOUSE, FRANCE SP SPIE, European Opt Soc, Ctr Natl Etud Spatiales, NASA DE radiometry; calibration; spectral response ID EARTH AB The objective of the current research is to minimize the theoretical uncertainty of the CERES ERBE-like level 1 instantaneous filtered and unfiltered radiance data products. The instrument's measured digital counts are converted to a filtered radiance by means of instrument calibration coefficients. The filtered radiance is then converted to an unfiltered radiance with an algorithm that utilizes the instrument's spectral response function. Uncertainties in the calibration sources and the spectral response function of the instrument can negatively affect the quality of the final data products. To reduce this effect, we are seeking to increase our understanding of the relative impact that various instrument and calibration parameters have on the level-1 filtered and unfiltered data products. Results of a statistical study of data products sensitivity to various instrument and calibration parameters axe presented. The sensitivity of the level-1 data products to the spectral response of the instrument when viewing non-Planck Earth scenes is also discussed. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Sorensen, IJ (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4265-8 J9 P SOC PHOTO-OPT INS PY 2001 VL 4540 BP 507 EP 517 DI 10.1117/12.450698 PG 11 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Instruments & Instrumentation; Remote Sensing SC Engineering; Instruments & Instrumentation; Remote Sensing GA BT92U UT WOS:000174463200056 ER PT S AU Kessel, RL AF Kessel, RL BE Warmbein, B TI ULF waves and the importance of Pc5 during high speed solar wind streams SO SHEFFIELD SPACE PLASMA MEETING: MULTIPOINT MEASUREMENT VERSUS THEORY, PROCEEDINGS: LES WOOLLISCROFT MEMORIAL CONFERENCE SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT Les Wolliscroft Memorial Conference/Sheffield Space Plasma Meeting on Multipoint Measurements Versus Theory CY APR 24-26, 2001 CL SHEFFIELD, ENGLAND ID MAGNETOHYDRODYNAMIC FLUCTUATIONS; DEPENDENCE; MAGNETOSPHERE; PULSATIONS; EVOLUTION; ORIGIN; POWER AB ULF waves have been studied in the interplanetary medium, upstream of planetary bow shocks, particularly at Earth, and in Earth's magnetosphere. Pc5 ULF waves have been studied extensively inside the magnetosphere, especially in conjunction with high speed solar wind streams occurring during the declining phase of the solar cycle. These are providing an excellent test bed for studying the transfer of mass, momentum, and energy through the solar-terrestrial space environment. High speed streams in 1995 already have been correlated with increased intensity of Pc5 ULF pulsations both in the equatorial outer zone and on the ground and with increased fluxes of energetic electrons in the outer zone of the magnetosphere. The Pc5 pulsations have been theorized to energize the electrons to relativistic levels. We have recently reported an additional correlation between high speed streams and Pc5 ULF waves upstream from Earth's bow shock. We have suggested that the streams provide a direct source of wave energy in the Pc5 range, and that this wave energy is transferred to the magnetosphere. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20770 USA. RP Kessel, RL (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20770 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-802-6 J9 ESA SP PUBL PY 2001 VL 492 BP 99 EP 105 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA BT55S UT WOS:000173316000014 ER PT J AU Ghoshal, A Parthan, S Hughes, D Schulz, MJ AF Ghoshal, A Parthan, S Hughes, D Schulz, MJ TI Free vibration characteristics of cylindrical shells using a wave propagation method SO SHOCK AND VIBRATION LA English DT Article ID PERIODIC AXIAL CURVATURE; STIFFENERS; BEAMS AB In the present piper, concept of a periodic structure is used to study the characteristics of the natural f'requencies of a complete unstiffened cylindrical shell. A segment of the shell between two consecutive nodal points is chosen to be a periodic structural element. The present effort is to modify Mead and Bardell's approach to study the free vibration characteristics of unstiffened cylindrical shell. The Love-Timoshenko formulation for the strain energy is used in conjunction with Hamilton's principle to compute the natural propagation constants for two shell geometries and different circumferential nodal patterns employing Floquet's principle. The natural frequencies were obtained using Sengupta's method and were compared with those obtained from classical Arnold-Warburton's method. The results from the wave propagation method were found to compare identically with the classical methods, since both the methods lead to the exact solution of the same problem. Thus consideration of the shell segment between two consecutive nodal points as a periodic Structure is validated. The variations of the phase constants at the lower bounding frequency for the first propagation band for different nodal patterns have been computed. The method is highly computationally efficient. C1 N Carolina Agr & Tech State Univ, NASA, Ctr Aerosp Res, Aerosp Struct Grp, Greensboro, NC 27410 USA. Indian Inst Technol, Dept Aerosp Engn, Kharagpur 721302, W Bengal, India. N Carolina Agr & Tech State Univ, Struct Dynam & Control Lab, Greensboro, NC 27410 USA. N Carolina Agr & Tech State Univ, Dept Mech Engn, Greensboro, NC 27410 USA. RP Ghoshal, A (reprint author), N Carolina Agr & Tech State Univ, NASA, Ctr Aerosp Res, Aerosp Struct Grp, 1601 E Market St, Greensboro, NC 27410 USA. NR 25 TC 4 Z9 4 U1 1 U2 2 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1070-9622 J9 SHOCK VIB JI Shock Vib. PY 2001 VL 8 IS 2 BP 71 EP 84 PG 14 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 473RB UT WOS:000171060800001 ER PT S AU Devaty, RP Bai, S Choyke, WJ Hobgood, D Larkin, DJ AF Devaty, RP Bai, S Choyke, WJ Hobgood, D Larkin, DJ BE Pensl, G Stephani, D Hundhausen, M TI Valence sand splittings of 15R SiC measured using wavelength modulated absorption spectroscopy SO SILICON CARBIDE AND RELATED MATERIALS, ECSCRM2000 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 3rd European Conference on Silicon Carbide and Related Materials CY SEP, 2000 CL KLOSTER BANZ, GERMANY SP Deutsch Forschung Gemeinschaft, European Commiss, High Level Sci Conf, US ARL European Res Off, US Off Naval Res Int Field Off, Cree, Axitron, DaimlerChrysler, Emcore, Epigress, H C Starck, Infineon Technologies, Leybold, NovaSiC, Omicron, Phys Tech, Saes Getters, SiCrystal, Siemens, Specs, Steag RTP Syst, Sterling Semicond, TDI, Triple O Microscopy, II VI Inc, Varian, Wacker Siltron DE absorption; band structure; crystal field splitting; spin orbit splitting; valence bands ID BAND-STRUCTURE; POLYTYPES AB 15R SiC has significant advantages over 4H and 6H SiC for certain device applications. We have measured the free exciton low temperature photoluminescence (LTPL) spectrum for E perpendicular to (c) over cap and the wavelength derivative of the absorption coefficient d alpha /d lambda, of 15R SiC for both polarizations E perpendicular to (c) over cap and E parallel to (c) over cap using modulation absorption spectroscopy. We use the E perpendicular to (c) over cap intrinsic 2 K photoluminescence spectrum to make assignments to features in the E perpendicular to (c) over cap absorption derivative spectrum. We obtain 7.15 +/-0.25 meV for the spin orbit splitting, in agreement with previous work, but with improved precision. The determination of the crystal field splitting is more challenging. We argue for a value of about SI meV. This value is in good agreement with recent calculations. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Cree Inc, Durham, NC 27703 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Devaty, RP (reprint author), Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-873-7 J9 MATER SCI FORUM PY 2001 VL 353-356 BP 357 EP 360 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing SC Materials Science GA BS06N UT WOS:000168535200087 ER PT B AU Zak, M AF Zak, M BE Giambiasi, N Frydman, C TI Dynamical networks with topological self-organization SO SIMULATION IN INDUSTRY 2001 LA English DT Proceedings Paper CT 13th European Simulation Symposium CY OCT 18-20, 2001 CL MARSEILLE, FRANCE SP Soc Comp Simulat, Soc Modeling & Simulat Int, ASIM, DIAM IUSPIM, Chinese Assoc Syst Simulat, Czech & Slovak Simulat Soc, European Simulat Council, Federat European Simulat Soc, Hungarian Simulat Soc, Japan Soc Simulat Technol, Latvian Simulat Soc, Turkish Simulat Soc DE tensor structure; attractors; self-organization AB Coupled evolution of state and topology of dynamical networks is introduced. Due to well organized tensor structure, the governing equations are presented in a canonical form, and required attractors as well as their basins can be easily implanted and controlled. This new class of dynamical networks can represent phenomenological models for self-organization of biomolecular sequences or of the genome in order to understand enormous complexity in their behavior. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Zak, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 90-77039-02-3 PY 2001 BP 709 EP 712 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BU02E UT WOS:000174740600127 ER PT B AU Kohen, HS Toomarian, N Bearman, GH Seligson, DB AF Kohen, HS Toomarian, N Bearman, GH Seligson, DB BE Giambiasi, N Frydman, C TI Cancer detection using neural computing methodology SO SIMULATION IN INDUSTRY 2001 LA English DT Proceedings Paper CT 13th European Simulation Symposium CY OCT 18-20, 2001 CL MARSEILLE, FRANCE SP Soc Comp Simulat, Soc Modeling & Simulat Int, ASIM, DIAM IUSPIM, Chinese Assoc Syst Simulat, Czech & Slovak Simulat Soc, European Simulat Council, Federat European Simulat Soc, Hungarian Simulat Soc, Japan Soc Simulat Technol, Latvian Simulat Soc, Turkish Simulat Soc DE cancer; neural network learning; morphology; molecular assessments; multi-spectral images; liquid crystal tunable filters. ID CLASSIFICATION AB This paper describes a novel learning methodology used to analyze bio-materials. The premise of this research is to help pathologists quickly identify anomalous cells in a cost efficient method. Skilled pathologists must methodically, efficiently and carefully analyze manually histopathologic materials for the presence, amount and degree of malignancy and/or other disease states. The prolonged attention required to accomplish this task induces fatigue that may result in a higher rate of diagnostic errors.. In addition, automated image analysis systems to date lack a sufficiently intelligent means of identifying even the most general regions of interest in tissue based studies and this shortfall greatly limits their utility. An intelligent data understanding system that could quickly and accurately identify diseased tissues and/or could choose regions of interest would be expected to increase the accuracy of diagnosis and usher in truly automated tissue based image analysis. We have developed a diagnostic tool (Bio-Analysis system) that uses a novel framework of morphological and molecular assessment of human histopathologic tissues based on multispectral signatures. The Bio-Analysis system creates multispectral imagery of tissue sections called 'BioCubes' and integrates them with neural network learning processing techniques to provide analysis and diagnosis capabilities. A complex ultra dimensional data set of bio-cubes of both benign and malignant prostate glandular epithelium was created and analyzed. In assigning either a benign or a malignant group designation to each gland, conclusive results were obtained with a high-speed turn-around and a 98% correct classification, as compared to manual analysis. System knowledge was gained by biologically inspired neural network learning algorithm generalization of spectral and spatial information. This technology can provide a human like learning process, which may eventually be utilized to help physicians more inexpensively and accurately diagnose normal vs. abnormal biological tissues. This methodology is also applicable to planet surface information gathering and to molecular assessment of bacteria. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kohen, HS (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 90-77039-02-3 PY 2001 BP 725 EP 729 PG 3 WC Computer Science, Artificial Intelligence; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BU02E UT WOS:000174740600130 ER PT B AU Timmerman, P Whitcannak, L Davies, E Deligianis, F AF Timmerman, P Whitcannak, L Davies, E Deligianis, F BE Das, RSL Frank, H TI Ultra-radiation hard aerospace batteries SO SIXTEENTH ANNUAL BATTERY CONFERENCE ON APPLICATIONS AND ADVANCES LA English DT Proceedings Paper CT 16th Annual Battery Conference on Applications and Advances CY JAN 09-12, 2001 CL CALIF STATE UNIV LONG BEACH, LONG BEACH, CA SP Amer Inst Aeronaut & Astronaut, Electrochem Soc Inc, Los Angeles City, Dept Water & Power, Independent Battery Manufacturers Assoc Inc, Int Cadmium Assoc (N Amer), Int Battery Technol Inc, SO Calif Edison Co, IEEE, Aerosp & Electr Syst Soc, Calif State, Dept Elect Engn HO CALIF STATE UNIV LONG BEACH C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Timmerman, P (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6545-3 PY 2001 BP 55 EP 55 DI 10.1109/BCAA.2001.905100 PG 1 WC Electrochemistry; Engineering, Electrical & Electronic SC Electrochemistry; Engineering GA BR58U UT WOS:000166855600009 ER PT B AU Manzo, MA Strawn, DM Hall, SW AF Manzo, MA Strawn, DM Hall, SW BE Das, RSL Frank, H TI Aerospace nickel-cadmium cell verification - Final report SO SIXTEENTH ANNUAL BATTERY CONFERENCE ON APPLICATIONS AND ADVANCES LA English DT Proceedings Paper CT 16th Annual Battery Conference on Applications and Advances CY JAN 09-12, 2001 CL CALIF STATE UNIV LONG BEACH, LONG BEACH, CA SP Amer Inst Aeronaut & Astronaut, Electrochem Soc Inc, Los Angeles City, Dept Water & Power, Independent Battery Manufacturers Assoc Inc, Int Cadmium Assoc (N Amer), Int Battery Technol Inc, SO Calif Edison Co, IEEE, Aerosp & Electr Syst Soc, Calif State, Dept Elect Engn HO CALIF STATE UNIV LONG BEACH AB During the early years of satellites, NASA successfully flew "NASA-Standard" nickel-cadmium (Ni-Cd) cells manufactured by GE/Gates/SAFT on a variety of spacecraft. In 1992 a NASA Battery Review Board determined that the strategy of a NASA Standard Cell and Battery Specification and the accompanying NASA control of a standard manufacturing control document (MCD) for Ni-Cd cells and batteries was unwarranted. As a result of that determination, standards were abandoned and the use of cells other than the NASA Standard was required. In order to gain insight into the performance and characteristics of the various aerospace Ni-Cd products available, tasks were initiated within the NASA Aerospace Flight Battery Systems Program that involved the procurement and testing of representative aerospace Ni-Cd cell designs. A standard set of test conditions was established in order to provide similar information about the products from various vendors. The objective of this testing was to provide independent verification of representative commercial flight cells available in the marketplace today. This paper will provide a summary of the verification tests run on cells from various manufacturers: Sanyo 35 Ampere-hour (Ah) standard and 35 Ah advanced Ni-Cd cells, SAFT 50 Ah Ni-Cd cells and Eagle-Picher 21 Ah Magnum and 21 Ah Super Ni-Cd-(TM) cells from Eagle-Picher were put through a full evaluation. A limited number of 18 Ah and 55 Ah cells from Acme Electric were also tested to provide an initial evaluation of the Acme aerospace cell designs. Additionally, 35 Ah aerospace design Ni-MH cells from Sanyo were evaluated under the standard conditions established for this program. The test program is essentially complete. The cell design parameters, the verification test plan and the details of the test result well will be discussed. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Manzo, MA (reprint author), NASA, Glenn Res Ctr, 21000 Brookpk Rd,MS 309-1, Cleveland, OH 44135 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6545-3 PY 2001 BP 59 EP 66 DI 10.1109/BCAA.2001.905101 PG 8 WC Electrochemistry; Engineering, Electrical & Electronic SC Electrochemistry; Engineering GA BR58U UT WOS:000166855600010 ER PT B AU West, WC Whitacre, JF Brandon, EJ Ratnakumar, BV AF West, WC Whitacre, JF Brandon, EJ Ratnakumar, BV BE Das, RSL Frank, H TI Lithium micro-battery development at the jet propulsion laboratory SO SIXTEENTH ANNUAL BATTERY CONFERENCE ON APPLICATIONS AND ADVANCES LA English DT Proceedings Paper CT 16th Annual Battery Conference on Applications and Advances CY JAN 09-12, 2001 CL CALIF STATE UNIV LONG BEACH, LONG BEACH, CA SP Amer Inst Aeronaut & Astronaut, Electrochem Soc Inc, Los Angeles City, Dept Water & Power, Independent Battery Manufacturers Assoc Inc, Int Cadmium Assoc (N Amer), Int Battery Technol Inc, SO Calif Edison Co, IEEE, Aerosp & Electr Syst Soc, Calif State, Dept Elect Engn HO CALIF STATE UNIV LONG BEACH AB Recent successes in the effort to miniaturize spacecraft components using MEMS technology, integrated passive components, and Low power electronics have driven the need for very low power, low profile, low mass micro-power sources for micro/nanospacecraft applications. Recent work at JPL has focused upon developing thin film/micro-batteries compatible with temperature sensitive substrates. A process to prepare crystalline LiCoO2 films with RF sputtering and moderate (<700C) annealing temperature has been developed. Thin film batteries with cathode films prepared with this process have specific capacities approaching the practical limit for LiCoO2, with acceptable rate capabilities and discharge voltage profiles. Solid state micro-scale batteries have also been fabricated, with feature sizes on the order of 50 microns. C1 Jet Prop Lab, Pasadena, CA 91109 USA. RP West, WC (reprint author), Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6545-3 PY 2001 BP 237 EP 241 DI 10.1109/BCAA.2001.905131 PG 5 WC Electrochemistry; Engineering, Electrical & Electronic SC Electrochemistry; Engineering GA BR58U UT WOS:000166855600040 ER PT B AU Ratnakumar, BV Smart, MC Whitcanack, L Davies, E Surampudi, S AF Ratnakumar, BV Smart, MC Whitcanack, L Davies, E Surampudi, S BE Das, RSL Frank, H TI Performance and safety of Li-ion cells SO SIXTEENTH ANNUAL BATTERY CONFERENCE ON APPLICATIONS AND ADVANCES LA English DT Meeting Abstract CT 16th Annual Battery Conference on Applications and Advances CY JAN 09-12, 2001 CL CALIF STATE UNIV LONG BEACH, LONG BEACH, CA SP Amer Inst Aeronaut & Astronaut, Electrochem Soc Inc, Los Angeles City, Dept Water & Power, Independent Battery Manufacturers Assoc Inc, Int Cadmium Assoc (N Amer), Int Battery Technol Inc, SO Calif Edison Co, IEEE, Aerosp & Electr Syst Soc, Calif State, Dept Elect Engn HO CALIF STATE UNIV LONG BEACH C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6545-3 PY 2001 BP 381 EP 381 DI 10.1109/BCAA.2001.905159 PG 1 WC Electrochemistry; Engineering, Electrical & Electronic SC Electrochemistry; Engineering GA BR58U UT WOS:000166855600066 ER PT B AU Feather, MS Fickas, S Razermera-Mamy, NA AF Feather, MS Fickas, S Razermera-Mamy, NA GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Model-checking for validation of a Fault Protection system SO SIXTH IEEE INTERNATIONAL SYMPOSIUM ON HIGH ASSURANCE SYSTEMS ENGINEERING LA English DT Proceedings Paper CT 6th IEEE International Symposium on High Assurance Systems Engineering CY OCT 22-24, 2001 CL BOCA RATON, FL SP IEEE Comp Soc Tech Comm Distribut Proc DE verification and validation; analysis; model checking; fault protection; state machines; message bus; NASA AB The Fault Protection (FP) system of a spacecraft is a critical component for its operation. The system diagnoses problems with the health of the spacecraft, and directs actions to resolve those problems. It therefore warrants a high degree of assurance as to its correctness. In this paper, we describe the use of model checking to help validate key requirements of such a FP system. The particular system we deal with is that of a genetic FP engine "networked" to the rest of the spacecraft. Its design is specified with a high degree of rigor, using state machine diagrams to define both the FP engine, and the spacecraft-specific responses that the engine directs. We describe the way we have modeled the FP engine and its operating environment so as to validate key requirements of its operation, and the influence of the above design characteristics on this effort. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Feather, MS (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 12 TC 2 Z9 2 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1275-5 PY 2001 BP 32 EP 41 DI 10.1109/HASE.2001.966805 PG 10 WC Computer Science, Information Systems; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BU53L UT WOS:000176274700003 ER PT S AU Adamovsky, G Lekki, J Sutter, JK Sarkisov, SS Curley, MJ Martin, CE AF Adamovsky, G Lekki, J Sutter, JK Sarkisov, SS Curley, MJ Martin, CE BE Sood, DK Lawes, RA Varadan, VV TI Smart microsystems with photonic element and their applications to aerospace platforms SO SMART STRUCTURES AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Symposium on Smart Materials and MEMS CY DEC 13-15, 2000 CL MELBOURNE, AUSTRALIA SP SPIE, Dept Def, Australia, Def Sci & Technol Org, State Govt Victoria, Australia, Victorian Dept State & Reg Dev, Swinburne Univ Technol DE fiber optics; photonics; sensing; actuation; smart systems; signal processing; vehicle health management ID PHOTOREFRACTIVE CRYSTALS; GRATINGS AB The need to make manufacturing, operation, and support of airborne vehicles safer and more efficient forces engineers and scientists to look for lighter, cheaper, more reliable technologies. Light weight, immunity to EMI, fire safety, high bandwidth, and high signal fidelity have already made photonics in general and fiber optics in particular an extremely attractive medium for communication purposes. With the fiber optics serving as a central nervous system of the vehicle, generation, detection, and processing of the signal occurs at the peripherals that include smart structures and devices. Due to their interdisciplinary nature, photonic technologies cover such diverse areas as optical sensors and actuators, embedded and distributed sensors, sensing schemes and architectures, harnesses and connectors, signal processing and algorithms. The paper includes a brief description of work in the photonic area that is going on at NASA, especially at the Glenn Research Center (GRC). C1 NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Adamovsky, G (reprint author), NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. NR 23 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3909-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4235 BP 407 EP 418 PG 12 WC Computer Science, Artificial Intelligence; Optics SC Computer Science; Optics GA BS26D UT WOS:000169262900042 ER PT S AU Turner, TL Lach, CL Cano, RJ AF Turner, TL Lach, CL Cano, RJ BE Lynch, CS TI Fabrication and characterization of SMA hybrid composites SO SMART STRUCTURES AND MATERIALS 2001: ACTIVE MATERIALS: BEHAVIOR AND MECHANICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE shape memory alloys; Nitinol; embedded actuators; hybrid composites; nonlinear thermoelasticity; composite fabrication; thermomechanical characterization AB Results from an effort to fabrication shape memory alloy hybrid composite (SMAHC) test specimens and characterize the material system are presented in this study. The SMAHC specimens are conventional composite structures with an embedded SMA constituent. The fabrication and characterization work was undertaken to better understand the mechanics of the material system, address fabrication issues cited in the literature, and provide specimens for experimental validation of a recently developed thermomechanical model for SMAHC structures. Processes and hardware developed for fabrication of the SMAHC specimens are described. Fabrication of a SMAHC laminate with quasi-isotropic lamination and ribbon-type Nitinol actuators embedded in the 0 degrees layers is presented. Beam specimens are machined from the laminate and are the focus of recent work, but the processes and hardware are readily extensible to more practical structures. Results of thermomechanical property testing on the composite matrix and Nitinol ribbon are presented. Test results from the Nitinol include stress-strain behavior, modulus versus temperature, and constrained recovery stress versus temperature and thermal cycle. Complex thermomechanical behaviors of the Nitinol and composite matrix are demonstrated, which have significant implications for modeling of SMAHC structures. C1 NASA, Langley Res Ctr, Struct Acoust Branch, Hampton, VA 23681 USA. RP Turner, TL (reprint author), NASA, Langley Res Ctr, Struct Acoust Branch, Mail Stop 463, Hampton, VA 23681 USA. NR 13 TC 20 Z9 20 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4019-1 J9 P SOC PHOTO-OPT INS PY 2001 VL 4333 BP 343 EP 354 DI 10.1117/12.432774 PG 12 WC Engineering, Electrical & Electronic; Engineering, Mechanical SC Engineering GA BT02A UT WOS:000171643800040 ER PT S AU Ounaies, Z Mossi, K Smith, R Bernd, J AF Ounaies, Z Mossi, K Smith, R Bernd, J BE Lynch, CS TI Low-field and high-field characterization of THUNDER actuators SO SMART STRUCTURES AND MATERIALS 2001: ACTIVE MATERIALS: BEHAVIOR AND MECHANICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE piezoelectric; pre-stressed ceramic; hysteresis; temperature effect; isothermal aging AB THUNDER (Thin Unimorph DrivER) actuators are pre-stressed piezoelectric devices developed at NASA LaRC that exhibit enhanced strain capabilities. As a result, they are of interest in a variety of aerospace applications. Characterization of their performance as a function of electric field, temperature and frequency is needed in order to optimize their operation. Towards that end, a number of THUNDER devices were obtained from FACE International Co. with a stainless steel substrate varying in thickness from 1 mil to 20 mils. The various devices were evaluated to determine low-field and high-field displacement as well as the polarization hysteresis loops. The thermal stability of these drivers was evaluated by two different methods. First, the samples were thermally cycled under electric field by systematically increasing the maximum temperature from 25 degreesC to 200 degreesC while the displacement was being measured. Second, the samples were isothermally aged at 0 degreesC, 50 degreesC, 100 degreesC and 150 degreesC in air, and the isothermal decay of the displacement was measured at room temperature as a function of time. C1 NASA, Langley Res Ctr, ICASE, Hampton, VA 23665 USA. RP Ounaies, Z (reprint author), NASA, Langley Res Ctr, ICASE, Hampton, VA 23665 USA. NR 8 TC 21 Z9 21 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4019-1 J9 P SOC PHOTO-OPT INS PY 2001 VL 4333 BP 399 EP 407 DI 10.1117/12.432779 PG 9 WC Engineering, Electrical & Electronic; Engineering, Mechanical SC Engineering GA BT02A UT WOS:000171643800045 ER PT S AU Bar-Cohen, Y AF Bar-Cohen, Y BE BarCohen, Y TI Transition of EAP material from novelty to practical applications - are we there yet? SO SMART STRUCTURES AND MATERIALS 2001: ELECTROACTIVE POLYMER ACTUATORS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE EAP; artificial muscles; EAP actuators; active polymers; medical EAP; manipulators AB For many years, EAPs received relatively little attention due to their limited actuation capability and the small number of available materials. In the last ten years, new EAP materials have emerged that exhibit large displacement response to electrical stimulation and they are enabling great potentials for the field. EAP are very attractive for their operational similarity to biological muscles, particularly their resilience, damage tolerant, and ability to induce large actuation strains. The application of these materials as actuators to drive various manipulation, mobility and robotic devices involves multidiscipline including materials, chemistry, electro-mechanics, computers, electronics, etc. Even though the force actuation of existing EAP materials and their robustness require further improvement, there has already been a series of reported successes. The successful devices that were reported include miniature manipulation devices including catheter steering element, miniature manipulator, dust-wiper, miniature robotic arm, grippers and others. Some of the currently considered applications may be difficult to accomplish and it is important to scope the requirements to the level that current materials can address. Using EAP to replace existing actuators may be a difficult challenge and therefore it is highly desirable to identify a niche application where it would not need to compete with existing capabilities. This paper will review the current efforts and the expectations for the future. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bar-Cohen, Y (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4015-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4329 BP 1 EP 6 DI 10.1117/12.432639 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Composites; Robotics; Optics; Polymer Science SC Engineering; Materials Science; Robotics; Optics; Polymer Science GA BT16G UT WOS:000172146700001 ER PT S AU Bar-Cohen, Y Sherrit, S Lih, SS AF Bar-Cohen, Y Sherrit, S Lih, SS BE BarCohen, Y TI Characterization of the electromechanical properties of EAP materials SO SMART STRUCTURES AND MATERIALS 2001: ELECTROACTIVE POLYMER ACTUATORS AND DEVICES SE Proceedings of SPIE LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE EAP; characterization; testing; electromechanical properties; electroactive polymers; actuators AB Electroactive polymers (EAP) are an emerging class of actuation materials. Their large electrically induced strains (longitudinal or bending), low density, mechanical flexibility, and ease of processing offer advantages over traditional electroactive materials. However, before the benefits of these materials can be exploited, their electrical and mechanical behavior must be properly quantified. Two general types of EAP can be identified. The first class is ionic EAP, which requires relatively low voltages (< 10V) to achieve large bending deflections. This class usually needs to be hydrated and electrochemical reactions may occur. The second class is Electronic-EAP and it involves piezoelectric, electrostrictive and/or Maxwell stresses. These materials can require large electric fields (> 100MV/m) to achieve longitudinal deformations at the range from 4 - 360%. Some of the difficulties in characterizing EAP include: nonlinear properties, large compliance (large mismatch with metal electrodes), nonhomogeneity (resulting from processing) and hysteresis. To support the need for reliable data, the authors are developing characterization techniques to quantify the electroactive responses and material properties of EAT materials. The emphasis of the current study is on addressing electromechanical issues related to the ion-exchange type EAP also known as IPMC. The analysis, experiments and test results are discussed in this paper. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 82-105, Pasadena, CA 91109 USA. EM yosi@jpl.nasa.gov NR 30 TC 21 Z9 21 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4015-9 J9 PROC SPIE PY 2001 VL 4329 BP 319 EP 327 DI 10.1117/12.432663 PG 9 WC Engineering, Electrical & Electronic; Materials Science, Composites; Robotics; Optics; Polymer Science SC Engineering; Materials Science; Robotics; Optics; Polymer Science GA BT16G UT WOS:000172146700038 ER PT S AU Bar-Cohen, Y Mavroidis, C Bouzit, MB Dolgin, B Harm, DL Kopchok, GE White, R AF Bar-Cohen, Y Mavroidis, C Bouzit, MB Dolgin, B Harm, DL Kopchok, GE White, R BE BarCohen, Y TI Virtual reality robotic telesurgery simulations using MEMICA haptic system SO SMART STRUCTURES AND MATERIALS 2001: ELECTROACTIVE POLYMER ACTUATORS AND DEVICES SE Proceedings of SPIE LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE haptic interfaces; MEMICA; virtual surgery; medical training; controlled stiffness; ERF; rheological fluids ID ELECTRORHEOLOGICAL FLUIDS; FEEDBACK AB There is increasing realization that some tasks can be performed significantly better by humans than robots but, due to associated hazards, distance, etc., only a robot can be employed. Telemedicine is one area where remotely controlled robots can have a major impact by providing urgent care at remote sites. In recent years, remotely controlled robotics has been greatly advanced and the NASA Johnson Space Center's robotic astronaut, "Robonaut," is one such example. Unfortunately, due to the unavailability of force and tactile feedback the operator must determine the required action by visually examining the remote site and therefore limiting the tasks that Robonaut can perform. There is a great need for dexterous, fast, accurate teleoperated robots with the operator's ability to "feel" the environment at the robot's field. The authors conceived a haptic mechanism called MEMICA (Remote MEchanical MIrroring using Controlled stiffness and Actuators) that can enable the design of high dexterity, rapid response, and large workspace haptic system. The development of a novel MEMICA gloves and virtual reality models are being explored to allow simulation of telesurgery and other applications. The MEMICA gloves are being designed to provide intuitive mirroring of the conditions at a virtual site where a robot simulates the presence of a human operator. The key components of MEMICA are miniature electrically controlled stiffness (ECS) elements and Electrically Controlled Force and Stiffness (ECFS) actuators that are based on the use of Electro-Rheological Fluids (ERF). In this paper the design of the MEMICA system and initial experimental results are presented. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Drive,MC 82-105, Pasadena, CA 91109 USA. EM yosi@jpl.nasa.gov NR 17 TC 5 Z9 5 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4015-9 J9 PROC SPIE PY 2001 VL 4329 BP 357 EP 363 DI 10.1117/12.432667 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Composites; Robotics; Optics; Polymer Science SC Engineering; Materials Science; Robotics; Optics; Polymer Science GA BT16G UT WOS:000172146700042 ER PT S AU Costen, RC Su, J Harrison, JS AF Costen, RC Su, J Harrison, JS BE BarCohen, Y TI Model for bending actuators that use electrostrictive graft elastomers SO SMART STRUCTURES AND MATERIALS 2001: ELECTROACTIVE POLYMER ACTUATORS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE electrostrictive; electromechanical; graft elastomers; actuators; modeling ID POLYURETHANE ELASTOMER; POLYMER DIELECTRICS AB Recently, it was reported that an electrostrictive graft elastomer exhibits large electric field-induced strain (4%). Combined with its high mechanical modulus, the elastomer can offer very promising electromechanical properties, in terms of output mechanical energy density, for an electroactive polymeric material. Therefore, it has been considered as one of the candidates, that can be used in high performance, low mass actuation devices in many aerospace applications. Various bilayer-based bending actuators have been designed and fabricated. An analytic model based on beam theory in the strength of materials has been derived for the transverse deflection, or curvature, and the longitudinal strain of the bi-layer beam.. The curvature and strain are functions of the applied voltage and the thickness, width, and Young's modulus of the active and passive layers. The model can be used to optimize the, performance of electrostrictive graft elastomer-based actuators to meet the requirements of various applications. In this, presentation, optimization and sensitivity studies are applied to the bending performance of such actuators. C1 NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. RP Costen, RC (reprint author), NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. NR 8 TC 2 Z9 2 U1 1 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4015-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4329 BP 436 EP 444 DI 10.1117/12.432677 PG 9 WC Engineering, Electrical & Electronic; Materials Science, Composites; Robotics; Optics; Polymer Science SC Engineering; Materials Science; Robotics; Optics; Polymer Science GA BT16G UT WOS:000172146700051 ER PT S AU Moses, RW Wieseman, CD Bent, AA Pizzochero, AE AF Moses, RW Wieseman, CD Bent, AA Pizzochero, AE BE McGowan, AMR TI Evaluation of new actuators in a buffet loads environment SO SMART STRUCTURES AND MATERIALS 2001: INDUSTRIAL AND COMMERCIAL APPLICATIONS OF SMART STRUCTURES TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE buffet loads alleviation; smart structures ID SCALE WIND-TUNNEL; PRESSURE MEASUREMENTS; F/A-18 TAIL AB Ongoing research in buffet loads alleviation has provided an application for recently developed piezoelectric actuators capable of higher force output than previously existing actuators could provide and that can be embedded within the vehicle's structure. These new actuators, having interdigitated electrodes, promise increased performance over previous piezoelectric actuators that were tested on the fin of an F/A-18 aircraft. Two new actuators being considered by the United States Air Force to reduce buffet loads on high performance aircraft were embedded into the fins of an F/A-18 wind-tunnel model and tested in the Transonic Dynamics Tunnel at the NASA Langley Research Center. The purpose of this test program, called ENABLE (Evaluation of New Actuators in a Buffet Loads Environment), was to examine the performance of the new actuators in alleviating fin buffeting, leading to a systems-level study of a fin buffet loads alleviation system architecture being considered by the USAF, Boeing, and NASA for implementation on high performance aircraft. During this wind-tunnel test, the two actuators per-formed superbly in alleviating fin buffeting. Peak values of the power spectral density functions for tip acceleration were reduced by as much as 85%. RMS values of tip acceleration were reduced by as much as 40% while using less than 50% of the actuators' capacity. Details of the wind-tunnel model and results of the wind-tunnel test are provided herein. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Moses, RW (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 20 TC 16 Z9 16 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4018-3 J9 P SOC PHOTO-OPT INS PY 2001 VL 4332 BP 10 EP 21 DI 10.1117/12.429653 PG 12 WC Engineering, Mechanical; Optics SC Engineering; Optics GA BT01Z UT WOS:000171643700002 ER PT S AU Horner, G Teter, J Robbins, E AF Horner, G Teter, J Robbins, E BE McGowan, AMR TI Flex patch, a highly flexible piezoceramic composite with attached electrical leads SO SMART STRUCTURES AND MATERIALS 2001: INDUSTRIAL AND COMMERCIAL APPLICATIONS OF SMART STRUCTURES TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab AB A new packaging technique for piezoceramic wafers is presented in which encapsulation of the piezoceramic incorporates the electrical leads. This technique for encapsulation produces a hermetically sealed package that also is flexible. The resulting product is called Flex-Patch because of the high flexibility. Micro-graphs of the flexed piezoceramic show that despite micro-cracking within the ceramic there is little, if any, loss in performance. Flex-Patch may be surface mounted or embedded into composites. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Horner, G (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 1 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4018-3 J9 P SOC PHOTO-OPT INS PY 2001 VL 4332 BP 259 EP 268 DI 10.1117/12.429665 PG 10 WC Engineering, Mechanical; Optics SC Engineering; Optics GA BT01Z UT WOS:000171643700028 ER PT S AU Washburn, AE AF Washburn, AE BE McGowan, AMR TI NASA micro-aero-adaptive control SO SMART STRUCTURES AND MATERIALS 2001: INDUSTRIAL AND COMMERCIAL APPLICATIONS OF SMART STRUCTURES TECHNOLOGIES SE Proceedings of SPIE LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE active flow control; synthetic jet; glow discharge; separation control; circulation control; viscous drag reduction; cavity; thrust vectoring ID TURBULENCE; SEPARATION; DELAY; JETS AB A summary of current research topics in active flow control at NASA Langley Research Center is presented. These topics are predominantly part of the Morphing Project, but closely related research topics from other projects are also included. A multi-disciplinary approach to technology development is being attempted that includes researchers from the more historical disciplines of fluid mechanics, acoustics, material science, structural mechanics, and control theory. The overall goals of the topics presented are focused on advancing the state of knowledge and understanding of controllable fundamental mechanisms in fluids rather than on specific engineering problems. The term "micro" used in the title indicates that the topics discussed are problems where a small, low-cost fluidic or shape-change input can create a large controllable output through the use of unsteady and nonlinear aerodynamics at receptive sites. Accompanying these fluid mechanics problems is the associated research in innovative actuators, sensors and control strategies including the development of design tools and system integration aids. The products of this research are to be demonstrated either in bench-top experiments, wind-tunnel tests, or in flight as part of the fundamental NASA R&D program and then transferred to more applied research programs within NASA, DOD, and U.S. industry. C1 NASA, Langley Res Ctr, Flor Phys & Control Branch, Hampton, VA 23681 USA. RP NASA, Langley Res Ctr, Flor Phys & Control Branch, MS 170, Hampton, VA 23681 USA. NR 69 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4018-3 J9 PROC SPIE PY 2001 VL 4332 BP 326 EP 344 DI 10.1117/12.429672 PG 19 WC Engineering, Mechanical; Optics SC Engineering; Optics GA BT01Z UT WOS:000171643700035 ER PT S AU Turner, TL AF Turner, TL BE Rao, VS TI Experimental validation of a thermoelastic model for SMA hybrid composites SO SMART STRUCTURES AND MATERIALS 2001: MODELING, SIGNAL PROCESSING, AND CONTROL IN SMART STRUCTURES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE shape memory alloys; Nitinol; embedded actuators; hybrid composites; nonlinear thermoelasticity; thermal buckling; thermal post-buckling; random response ID SHAPE-MEMORY MATERIALS; ALLOY AB This study presents results from experimental validation of a recently developed model for predicting the thermomechanical behavior of shape memory alloy hybrid composite (SMAHC) structures, composite structures with an embedded SMA constituent. The model captures the material nonlinearity of the material system with temperature and is capable of modeling constrained, restrained, or free recovery behavior from experimental measurement of fundamental engineering properties. A brief description of the model and analysis procedures is given, followed by an overview of a parallel effort to fabricate and characterize the material system of SMAHC specimens. Static and dynamic experimental configurations for the SMAHC specimens are described and experimental results for thermal post-buckling and random response are presented. Excellent agreement is achieved between the measured and predicted results, fully validating the theoretical model for constrained recovery behavior of SMAHC structures. C1 NASA, Langley Res Ctr, Struct Acoust Branch, Hampton, VA 23681 USA. RP Turner, TL (reprint author), NASA, Langley Res Ctr, Struct Acoust Branch, Mail Stop 463, Hampton, VA 23681 USA. NR 16 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4012-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4326 BP 208 EP 219 DI 10.1117/12.436475 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Industrial SC Computer Science; Engineering GA BT28J UT WOS:000172533200021 ER PT S AU Lekki, JD Adamovsky, G Floyd, B AF Lekki, JD Adamovsky, G Floyd, B BE Udd, E Inaudi, D TI Demodulation system for fiber optic Bragg grating dynamic pressure sensing SO SMART STRUCTURES AND MATERIALS 2001: SENSORY PHENOMENA AND MEASUREMENT INSTRUMENTATION FOR SMART STRUCTURES AND MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE fiber; sensor; interferometer; Bragg grating ID STRAIN SENSOR AB Fiber optic Bragg gratings have been used for years to measure quasi-static phenomena. In aircraft engine applications there is a need to measure dynamic signals such as variable pressures. In order to monitor these pressures a detection system with broad dynamic range is needed. This paper describes an interferometric demodulator that was developed and optimized for this particular application. The signal to noise ratio was maximized through temporal coherence analysis. The demodulator was incorporated in a laboratory system that simulates conditions to be measured. Several pressure sensor configurations incorporating a fiber optic Bragg grating were also explored. The results of the experiments are reported in this paper. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Lekki, JD (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4014-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4328 BP 151 EP 159 DI 10.1117/12.435517 PG 9 WC Acoustics; Instruments & Instrumentation; Materials Science, Composites; Optics SC Acoustics; Instruments & Instrumentation; Materials Science; Optics GA BT33W UT WOS:000172674900018 ER PT S AU Choi, SH Golembiewski, WT Song, KD Bryant, RG AF Choi, SH Golembiewski, WT Song, KD Bryant, RG BE Varadan, VK TI Networked smart material actuators with rectenna array SO SMART STRUCTURES AND MATERIALS 2001: SMART ELECTRONICS AND MEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE smart actuators; rectenna; power allocation and distribution ID SURFACE AB The concept of microwave-driven smart material actuators is envisioned as, the best option to, alleviate the complexity associated with hard-wired control circuitry. Networked rectenna patch array receives and converts microwave power into a DC power for an array of smart actuators. To use microwave power effectively, the concept of a power allocation and distribution (PAD) circuit is adopted for networking a recterma/actuator patch array. The PAD circuit is imbedded into a single embodiment of rectenna and actuator array. The thin-film, microcircuit embodiment of PAD circuit adds, insignificant amount of rigidity to membrane flexibility. Preliminary design and fabrication of PAD circuitry that consists of a few nodal elements were made for laboratory testing The networked actuators were tested to correlate the network coupling effect, power allocation and distribution, and response time. The features of preliminary design are 16-channel computer control of actuators by a PCI board and the compensator for a power failure or leakage of one or more rectennas. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Choi, SH (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 17 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4020-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4334 BP 372 EP 381 DI 10.1117/12.436623 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT16H UT WOS:000172146800042 ER PT S AU Bar-Cohen, Y Chang, ZS AF Bar-Cohen, Y Chang, ZS BE Davis, LP TI Piezoelectrically actuated miniature peristaltic pump SO SMART STRUCTURES AND MATERIALS 2001: SMART STRUCTURES AND INTEGRATED SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE pumps; piezoelectric actuation; piezopump; peristaltic pump; actuators AB There is a range of NASA experiments, instruments and applications where miniature pumps are needed. To address such needs, a piezoelectrically actuated miniature pump is being developed. This pump employs a novel volume displacing mechanism using flexural traveling waves that acts peristaltically and eliminates the need for valves or physically moving parts. This pump is being developed for planetary instruments and space applications. Finite element model was developed using ANSYS for the purpose of prediction of the resonance frequency of the vibrating mode for the piezo-pump driving stator. The model allows determining simultaneously the mode shapes that are associated with the various resonance frequencies. This capability is essential for designing the pump size and geometry. To predict and optimize the pump efficiency that is determined by the volume of pumping chambers the model was modified to perform harmonic analysis. Current capability allows the determination of the effect of such design parameters as pump geometry, construction materials and operating modes on the volume of the chambers that are formed between the peaks and valleys of the waves. Experiments were made using a breadboard of the pump and showed water-pumping rate of about 4.5 cc/min. The pump is continually being modified to enhance the performance and efficiency. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bar-Cohen, Y (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 10 TC 5 Z9 5 U1 3 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4013-2 J9 P SOC PHOTO-OPT INS PY 2001 VL 4327 BP 425 EP 432 DI 10.1117/12.436554 PG 8 WC Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BT26D UT WOS:000172441200041 ER PT S AU Bar-Cohen, Y Sherrit, S Dolgin, BP Bao, XQ Chang, ZS Pal, DS Krahe, R Kroh, J Du, S Peterson, T AF Bar-Cohen, Y Sherrit, S Dolgin, BP Bao, XQ Chang, ZS Pal, DS Krahe, R Kroh, J Du, S Peterson, T BE Davis, LP TI Ultrasonic/sonic drilling/coring (USDC) for planetary applications SO SMART STRUCTURES AND MATERIALS 2001: SMART STRUCTURES AND INTEGRATED SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 2001 Conference CY MAR 05-08, 2001 CL NEWPORT BEACH, CA SP SPIE, Amer Soc Mech Engineers, Soc Exptl Mech, Boeing Co, USAF Res Lab, DARPA, Ceram Soc Japan, Intelligent Mat Forum, USA Res Off, Jet Propuls Lab DE drilling; coring; USDC; planetary sampling; ultrasonic drilling; in-situ analysis AB Future NASA exploration missions are increasingly seeking to conduct sampling, in-situ analysis and possibly return samples to Earth for further tests. Missions to Mars are the more near term projects that are seeking such capabilities. One of the major limitations of sampling on Mars and other low gravity environments is the need for high axial force when using conventional drilling. To address this limitation an ultrasonic/sonic drilling/coring (USDC) mechanism has been developed that employs an ultrasonic horn driven by a piezoelectric stack. The horn drives a free mass that resonates between the hom and drill stem. Tests have shown that the USDC addresses some of the key challenges to the NASA sampling objectives. The USDC is lightweight (450 g), requires low preload (< 5N) and can be driven at low power (5W). The device has been shown to drill rocks with various levels of hardness including granite, diorite, basalt and limestone. The hammering action involved with the coring process can produce cores of various shapes, which need not necessarily be round. Because it is driven by piezoelectric ceramics, the USDC is highly tolerant to changes in its operating environment. These actuation materials can be designed to operate at a wide range of temperatures including those expected on Mars and Venus. Although the drill is driven electrically at 20 kHz, a substantial sub-harmonic acoustic component is found that is crucial to drilling performance. An analytical model has been developed to explain this low frequency coupling in the horn, free mass, drill stem and rock. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bar-Cohen, Y (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 4 TC 3 Z9 3 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4013-2 J9 P SOC PHOTO-OPT INS PY 2001 VL 4327 BP 441 EP 448 DI 10.1117/12.436556 PG 8 WC Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BT26D UT WOS:000172441200043 ER PT B AU Venneri, SL AF Venneri, SL BE Roco, MC Bainbridge, WS TI Implications of nanotechnology for space exploration SO SOCIETAL IMPLICATIONS OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Proceedings Paper CT Workshop on Societal Implications of Nanoscience and Nanotechnology CY SEP 28-29, 2000 CL NATL SCI FDN, ARLINGTON, VA HO NATL SCI FDN AB Typically when NASA begins a new technology program the Agency is most concerned about the performance benefits, cost of development, time for development and new opportunities that are enabled. Ethics becomes part of the process if the development or ultimate use of the technology directly affects the health or well being of humans or other living creatures. However, as we move into the era of nanotechnology we are also encompassing biology and fundamental biological processes. Our vision of nanotechnology encompasses the attributes of self-generation, reproduction, self-assembly, self-repair and natural adaptation. These are all attributes we ascribe to living things. Thus, we are moving beyond the typical bounds of technology into the domain of natural philosophy. This can have significant implications for the public attitude toward such technology. Nanotechnology will enable NASA to build future systems with many of these "life-like" characteristics. We need this capability for our robotic systems to operate at great distances from Earth, in harsh environments without the benefit and high cost of continuous human control. As we develop new nanotechnology we must also pro-actively establish policies and guidelines to assure the technology and systems made from it are socially acceptable to the general public. C1 NASA, Washington, DC 20546 USA. RP Venneri, SL (reprint author), NASA, Headquarters Bldg,Rm 9S13, Washington, DC 20546 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-7178-X PY 2001 BP 213 EP 218 PG 6 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary; Social Issues SC Engineering; Materials Science; Social Issues GA BV19G UT WOS:000178107000028 ER PT S AU Reames, DV AF Reames, DV BE WimmerSchweingruber, RF TI Energetic particle composition SO SOLAR AND GALACTIC COMPOSITION SE AIP Conference Proceedings LA English DT Proceedings Paper CT Joint SOHO/ACE Workshop on Solar and Galactic Composition CY MAR 06-09, 2001 CL BERN, SWITZERLAND SP European Space Agcy, Schweizer Natl Fonds Forder Wissensch, Oerlikon Contraves Space SA, Univ Bern, Physikal Inst ID CORONAL MASS EJECTIONS; MEAN IONIC CHARGE; SOLAR-FLARES; COSMIC-RAYS; EVENTS; ACCELERATION; ABUNDANCES; HE-3; ENHANCEMENTS; HELIOSPHERE AB Abundances of elements and isotopes have been essential for identifying and measuring the sources of the energetic ions and for studying the physical processes of acceleration and transport for each particle population in the heliosphere. Many of the sources are surprising, in a few cases the acceleration bias is extreme, but an understanding of the fundamental physics allows us to use energetic ions to determine abundances for the average solar corona, the highspeed solar wind, and the local interstellar medium. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 48 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0042-3 J9 AIP CONF PROC PY 2001 VL 598 BP 153 EP 164 PG 12 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BT59T UT WOS:000173445900023 ER PT S AU Slocum, PL Christian, ER Cohen, CMS Cummings, AC Leske, RA Mewaldt, RA Stone, EC von Rosenvinge, TT Wiedenbeck, ME AF Slocum, PL Christian, ER Cohen, CMS Cummings, AC Leske, RA Mewaldt, RA Stone, EC von Rosenvinge, TT Wiedenbeck, ME BE WimmerSchweingruber, RF TI Measurements of heavy elements and isotopes in small solar energetic particle events SO SOLAR AND GALACTIC COMPOSITION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Joint SOHO/ACE Workshop on Solar and Galactic Composition CY MAR 06-09, 2001 CL BERN, SWITZERLAND SP European Space Agcy, Schweizer Natl Fonds Forder Wissensch, Oerlikon Contraves Space SA, Univ Bern, Physikal Inst ID ABUNDANCES; FLARES; HE-3; ACCELERATION; SUN AB Using the Solar Isotope Spectrometer on the Advanced Composition Explorer, we have examined the similar to10-20 MeV/nucleon elemental and isotopic composition of heavy (Zgreater than or equal to6) energetic nuclei accelerated in 30 small solar energetic particle (SEP) events which occurred between 31 March 1998 and 2 January 2001. We have measured the average heavy element content, the Ne-22/Ne-20 ratio, and the Mg-26/Mg-24 ratio in these events, and find good agreement with past studies. We have categorized the events according to their He-3/He-4 ratios, and find significant enhancements in the neutron-rich heavy isotopes of Ne and Mg in the combined He-3-rich data set: Ne-22/Ne-20=0.17+/-0.05 and Mg-26/Mg-24=0.25+/-0.05. We discuss the implications of these measurements for the acceleration of energetic nuclei in SEP events. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Slocum, PL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. RI Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 24 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0042-3 J9 AIP CONF PROC PY 2001 VL 598 BP 177 EP 182 PG 6 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BT59T UT WOS:000173445900026 ER PT S AU de Nolfo, GA Yanasak, NE Binns, WR Cummings, AC Christian, ER George, JS Hink, PL Israel, MH Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT Wiedenbeck, ME AF de Nolfo, GA Yanasak, NE Binns, WR Cummings, AC Christian, ER George, JS Hink, PL Israel, MH Leske, RA Lijowski, M Mewaldt, RA Stone, EC von Rosenvinge, TT Wiedenbeck, ME BE WimmerSchweingruber, RF TI Measurements of the isotopes of lithium, beryllium, and boron from ACE/CRIS SO SOLAR AND GALACTIC COMPOSITION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Joint SOHO/ACE Workshop on Solar and Galactic Composition CY MAR 06-09, 2001 CL BERN, SWITZERLAND SP European Space Agcy, Schweizer Natl Fonds Forder Wissensch, Oerlikon Contraves Space SA, Univ Bern, Physikal Inst ID GALACTIC COSMIC-RAYS; STAR-FORMING REGIONS; LIGHT-ELEMENTS; SUPERNOVA-REMNANTS; EVOLUTION; SOLAR; NUCLEOSYNTHESIS; NUCLEI; ORIGIN AB The isotopes of lithium, beryllium, and boron (LiBeB) are known in nature to be produced primarily by CNO spallation and alpha - alpha fusion from interactions between cosmic rays and interstellar nuclei. While the dominant source of LiBeB isotopes in the present epoch is cosmic-ray interactions, other sources are known to exist, including the production of Li-7 from big bang nucleosynthesis. Precise observations of galactic cosmic-ray LiBeB in addition to accurate modeling of cosmic-ray transport can help to constrain the relative importance among the different production mechanisms. The Cosmic Ray Isotope Spectrometer (CRIS) on the Advanced Composition Explorer (ACE) has measured nuclei with 2 less than or similar to Z less than or similar to 30 in the energy range similar to30-500 MeV/nucleon since 1997 with good statistical accuracy. We present measurements of the isotopic abundances of LiBeB and discuss these observations in the context of previous cosmic-ray measurements and spectroscopic observations. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP de Nolfo, GA (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RI de Nolfo, Georgia/E-1500-2012; Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 31 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0042-3 J9 AIP CONF PROC PY 2001 VL 598 BP 251 EP 255 PG 5 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BT59T UT WOS:000173445900036 ER PT S AU Wiedenbeck, ME Binns, WR Christian, ER Cummings, AC Davis, AJ George, JS Hink, PL Israel, MH Leske, RA Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE AF Wiedenbeck, ME Binns, WR Christian, ER Cummings, AC Davis, AJ George, JS Hink, PL Israel, MH Leske, RA Mewaldt, RA Stone, EC von Rosenvinge, TT Yanasak, NE BE WimmerSchweingruber, RF TI Constraints on the nucleosynthesis of refractory nuclides in galactic cosmic rays SO SOLAR AND GALACTIC COMPOSITION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Joint SOHO/ACE Workshop on Solar and Galactic Composition CY MAR 06-09, 2001 CL BERN, SWITZERLAND SP European Space Agcy, Schweizer Natl Fonds Forder Wissensch, Oerlikon Contraves Space SA, Univ Bern, Physikal Inst ID II SUPERNOVAE; ABUNDANCES; ELEMENTS; NI AB Abundances of the isotopes of the refractory elements Ca, Fe, Co, and Ni in the galactic cosmic-ray source are compared with corresponding abundances in solar-system matter. For the 12 nuclides considered, relative abundances agree to within a factor of 2, and typically within 20-30%. In addition, comparisons of cosmic-ray abundances with model calculations of supernova yields are used to argue that cosmic rays contain contributions from stars with a broad range of masses. Based on these and other results we suggest that cosmic rays probably represent a sample of contemporary interstellar matter, at least for refractory species. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Wiedenbeck, ME (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 14 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0042-3 J9 AIP CONF PROC PY 2001 VL 598 BP 269 EP 274 PG 6 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BT59T UT WOS:000173445900039 ER PT S AU Keller, JW Coplan, MA Lorenz, JE Ogilve, KW AF Keller, JW Coplan, MA Lorenz, JE Ogilve, KW BE WimmerSchweingruber, RF TI New concept for the measurement of energetic neutral atom composition and the imaging of their sources SO SOLAR AND GALACTIC COMPOSITION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Joint SOHO/ACE Workshop on Solar and Galactic Composition CY MAR 06-09, 2001 CL BERN, SWITZERLAND SP European Space Agcy, Schweizer Natl Fonds Forder Wissensch, Oerlikon Contraves Space SA, Univ Bern, Physikal Inst AB Enrgetic neutral atoms created by charge neutralization of ions convey information about the region from which they originate. Free of magnetic and electric fields the neutrals travel in straight lines and can be observed far from their source. The neutrals provide the means for imaging planetary magnetospheres and studying the interstellar gas and the neutral solar wind. Neutral atoms with energies above a few keV can be observed with instruments that are largely modifications of devices already designed to detect ions. For neutrals with lower energies, other techniques are required. We present a new concept for detecting and imaging neutral atoms below I keV energy that has the potential for improving detection efficiency and resolution by a factor of ten over existing methods. The proposed instrument will use an excited-atom electron-attachment cell for high neutral to ion conversion efficiency. A novel method to contain the gas but allow incident neutral atoms and converted ions to pass into and out of the cell with high efficiency is presented. Applications of the detector are discussed. C1 Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Keller, JW (reprint author), Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Keller, John/I-5097-2013 NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0042-3 J9 AIP CONF PROC PY 2001 VL 598 BP 291 EP 296 PG 6 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BT59T UT WOS:000173445900042 ER PT S AU Jones, FC Baring, MG Ellison, DC AF Jones, FC Baring, MG Ellison, DC BE WimmerSchweingruber, RF TI The effect of self-consistent stochastic preacceleration of pickup ions on the composition of anomalous cosmic rays. SO SOLAR AND GALACTIC COMPOSITION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Joint SOHO/ACE Workshop on Solar and Galactic Composition CY MAR 06-09, 2001 CL BERN, SWITZERLAND SP European Space Agcy, Schweizer Natl Fonds Forder Wissensch, Oerlikon Contraves Space SA, Univ Bern, Physikal Inst ID TERMINATION SHOCK; ACCELERATION; HELIOSPHERE AB We have previously calculated the spectrum of anomalous cosmic rays (ACR) by employing the supposed spectrum of interstellar pickup ions as the seed population for a Monte Carlo model of the solar wind termination shock. This pickup ion spectrum was extrapolated from measurements some distance from the shock under the assumption that adiabatic loss was the only energy change process acting prior to reaching the shock. Our results while reasonable in many respects were underabundant in He+ and O+ ions relative to H+ as determined by observation. le Roux and Ptuskin have shown that stochastic preacceleration is more effective for He+ and O+ ions than for H+ ions thereby redressing this underabundance. We have employed the results of le Roux and Ptuskin as input to our previous model and will show to what extent the relative abundances are improved thereby. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Jones, FC (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0042-3 J9 AIP CONF PROC PY 2001 VL 598 BP 335 EP 337 PG 3 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BT59T UT WOS:000173445900049 ER PT S AU von Rosenvinge, TT Cohen, CMS Christian, ER Cummings, AC Leske, RA Mewaldt, RA Slocum, PL Cyr, OCS Stone, EC Wiedenbeck, ME AF von Rosenvinge, TT Cohen, CMS Christian, ER Cummings, AC Leske, RA Mewaldt, RA Slocum, PL Cyr, OCS Stone, EC Wiedenbeck, ME BE WimmerSchweingruber, RF TI Time variations in elemental abundances in solar energetic particle events SO SOLAR AND GALACTIC COMPOSITION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Joint SOHO/ACE Workshop on Solar and Galactic Composition CY MAR 06-09, 2001 CL BERN, SWITZERLAND SP European Space Agcy, Schweizer Natl Fonds Forder Wissensch, Oerlikon Contraves Space SA, Univ Bern, Physikal Inst ID ACCELERATION; ACE; EVOLUTION; WIND AB The Solar Isotope Spectrometer (SIS) on-board the Advanced Composition Explorer has a large collection power and high telemetry rate, making it possible to study elemental abundances in large solar energetic particle (SEP) events as a function of time. Results have now been obtained for more than 25 such events. Understanding the causes of these variations is key to obtaining reliable solar elemental abundances and to understanding solar acceleration processes. Such variations have been previously attributed to two models: (1) a mixture of an initial impulsive phase having enhanced heavy element abundances with a longer gradual phase with coronal abundances and (2) rigidity dependent escape from CME-driven shocks through plasma waves generated by wave-particle interactions. In this second model the injected abundances are assumed to be coronal. Both these models can be expected to depend upon solar longitude since impulsive events axe associated with flares at longitudes well-connected magnetically to the observer, and shock properties and connection of the observer to the shock are also longitude dependent. We present results on temporal variations from event to event and within events and show that they appear to have a longitude dependence. We show that the events which have been well-explained by model (2) tend to be near central meridian or the west limb. In addition, we show that there are events with little time variation and heavy element enhancements similar to those of impulsive events. These events seem to be better explained by model (1) with only an impulsive phase. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP von Rosenvinge, TT (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Christian, Eric/D-4974-2012 OI Christian, Eric/0000-0003-2134-3937 NR 24 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0042-3 J9 AIP CONF PROC PY 2001 VL 598 BP 343 EP 348 PG 6 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BT59T UT WOS:000173445900051 ER PT S AU Abdeldayem, H Frazier, D Paley, MS AF Abdeldayem, H Frazier, D Paley, MS BE Lampert, CM Granqvist, CG Lewis, KL TI Polydiacetylene as an all-optical picosecond switch SO SOLAR AND SWITCHING MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Solar and Switching Materials CY AUG 01-02, 2001 CL SAN DIEGO, CA SP SPIE DE All-Optical switch; Z-scan; Polydiacetylene; thin film; organic; nonlinear optics; optical computing; Logic-gate ID CONJUGATED POLYMER AB Polydiacetylene derivative of 2-methyl-4-nitroaniline (PDAMNA) shows a picosecond switching property, which illustrated a partial all-optical picosecond NAND logic gate. The switching phenomenon was demonstrated by waveguiding two collinear beams at 633 nm and 532 run through a hollow fiber of 50 mum diameter, coated from inside with a thin film of PDAMNA. A Z-scan investigations of a PDAMNA thin film on quartz substrate revealed that the switching effect was attributed to an excited state absorption in the systems. The studies also showed that the polymer suffers a photo-oxidation beyond an intensity level of 2.9x10(6) w/cm(2). The photo-oxidized film has different physical properties that are different from the original film before oxidation. The life time of both excited states before and after oxidation as well as their absorption coefficients were estimated by fitting a three level system model to the experimental results. C1 NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc SD47, Huntsville, AL 35812 USA. RP Abdeldayem, H (reprint author), NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc SD47, Bldg 4481, Huntsville, AL 35812 USA. NR 24 TC 1 Z9 1 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4172-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4458 BP 240 EP 247 DI 10.1117/12.448255 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics; Physics, Condensed Matter SC Engineering; Materials Science; Optics; Physics GA BU48M UT WOS:000176126000029 ER PT S AU Szabo, A Lepping, RP Merka, J Smith, CW Skoug, RM AF Szabo, A Lepping, RP Merka, J Smith, CW Skoug, RM BE Battrick, B SawayaLacoste, H TI The evolution of interplanetary shocks driven by magnetic clouds SO SOLAR ENCOUNTER SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 1st Solar Orbiter Workshop CY MAY 14-18, 2001 CL PUERTO LA CRUZ, SPAIN SP European Space Agcy, Inst Astrofis Canarias ID RANKINE-HUGONIOT PROBLEM; AU AB As fast moving magnetic clouds travel through the variable inner heliospheric medium, the driven shocks have to adjust their characteristics and shape to reflect the local ambient solar wind conditions. Current, near-Earth, multi-point observations give us a limited insight of the final shape and properties of these driven shocks just before they impinge on the Earth's magnetosphere. ACE, WIND and IMP 8 measurements of interplanetary shocks driven by well-formed, force free fluxrope magnetic clouds observed during the rising phase of the past solar cycle (1995-1999), reveal that though, on average, the shock surface geometry is closer to planar, it has still significant deformations on the scale-length of the magnetosphere. In particular, fast and large magnetic clouds, intercepted at low impact parameters, tend to have the most planar driven shocks. The fitted shock normals indicate flaring with respect to the cloud axis and significant surface corrugation. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Szabo, A (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 17 TC 14 Z9 14 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-803-4 J9 ESA SP PUBL PY 2001 VL 493 BP 383 EP 387 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT66T UT WOS:000173695900065 ER PT S AU Vaisberg, O Goldstein, B Chornay, D Keller, J Avanov, L Smirnov, V Brinza, D Croley, D Sittler, E Moore, T Rozmarynowski, P Fuselier, S Ghielmetti, A AF Vaisberg, O Goldstein, B Chornay, D Keller, J Avanov, L Smirnov, V Brinza, D Croley, D Sittler, E Moore, T Rozmarynowski, P Fuselier, S Ghielmetti, A BE Battrick, B SawayaLacoste, H TI Ultra fast plasma analyzer - An all-sky camera for charged particles SO SOLAR ENCOUNTER SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 1st Solar Orbiter Workshop CY MAY 14-18, 2001 CL PUERTO LA CRUZ, SPAIN SP European Space Agcy, Inst Astrofis Canarias AB We address an issue of providing wide un-obscured field of view and fast data acquisition of the charged particles. The goal is achieved with cylindrically symmetric electrostatic mirror and single imaging detector. The use of mirror limits the upper limit of instrument by about 10 keV. An example is given that provides complete 2pi field of view, or all-sky charged particles camera. Adaptation to specific requirements of the experiment is feasible, including modification of field of view and additional energy and mass analyzers. For example, solar wind measurements can be performed with desired detail by modifying the mirror for this purpose. Full 4pi field of view can be covered with 2 analyzers located at the opposite sides of spacecraft. Both pseudo-integral and differential energy selection measurements are possible. High degree of UV rejection is achieved by the use of secondary mirror and intermediate particle focusing. Very high temporal resolution is feasible. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Vaisberg, O (reprint author), NASA, Goddard Space Flight Ctr, Code 692, Greenbelt, MD 20771 USA. RI Keller, John/I-5097-2013 NR 5 TC 5 Z9 5 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-803-4 J9 ESA SP PUBL PY 2001 VL 493 BP 451 EP 454 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT66T UT WOS:000173695900078 ER PT S AU Ruzmaikin, A AF Ruzmaikin, A BE Battrick, B SawayaLacoste, H TI A search for the source spectrum of solar wind fluctuations SO SOLAR ENCOUNTER SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 1st Solar Orbiter Workshop CY MAY 14-18, 2001 CL PUERTO LA CRUZ, SPAIN SP European Space Agcy, Inst Astrofis Canarias DE solar wind; magnetic fluctuations; co-rotation ID 1/F NOISE; TURBULENCE AB The Solar Orbiter will open a unique opportunity to measure for the first time the spectrum of fluctuations in the solar wind produced by localized solar source. It can be done during the co-rotation phase of the Solar Orbiter mission. All previous measurements have averaged the fluctuations over many sources distributed on the Sun. The spectrum of magnetic (as well as perpendicular velocity) fluctuations in the low-frequency spectral range is predicted to be very different from the 1/f spectrum measured in the absence of co-rotation. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ruzmaikin, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-803-4 J9 ESA SP PUBL PY 2001 VL 493 BP 455 EP 457 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT66T UT WOS:000173695900079 ER PT J AU Gary, GA AF Gary, GA TI Plasma beta above a solar active region: Rethinking the paradigm SO SOLAR PHYSICS LA English DT Article ID CORONAL MAGNETIC-FIELD; FORCE-FREE; TRANSITION REGION; LOOPS; STRENGTH; LINES; SUN; EXTRAPOLATION; TEMPERATURE; COMPONENTS AB In this paper, we present a model of the plasma beta above an active region and discuss its consequences in terms of coronal magnetic field modeling. The beta -plasma model is representative and derived from a collection of sources. The resulting beta variation with height in the solar atmosphere is used to emphasize that the assumption that the magnetic pressure dominates over the plasma pressure must be carefully employed when extrapolating the magnetic field. This paper points out (1) that the paradigm that the coronal magnetic field can be constructed from a force-free magnetic field must be used in the correct context, since the force-free region is sandwiched between two regions which have beta >1, (2) that the chromospheric Mg ii-C iv magnetic measurements occur near the beta -minimum, and (3) that, moving from the photosphere upwards, beta can return to similar to1 at relatively low coronal heights, e.g., R similar to1.2 R-s. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. EM Allen.Gary@msfc.nasa.gov NR 48 TC 240 Z9 245 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 EI 1573-093X J9 SOL PHYS JI Sol. Phys. PY 2001 VL 203 IS 1 BP 71 EP 86 DI 10.1023/A:1012722021820 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492MR UT WOS:000172172600006 ER PT J AU Benz, AO Lin, RP Sheiner, OA Krucker, S Fainberg, J AF Benz, AO Lin, RP Sheiner, OA Krucker, S Fainberg, J TI The source regions of impulsive solar electron events SO SOLAR PHYSICS LA English DT Article ID RADIO-BURSTS; FLARES AB Low-energy (2-19 keV) impulsive electron events observed in interplanetary space have been traced back to the Sun, using their interplanetary type III radiation and metric/decimetric radio-spectrograms. For the first time we are able to study the highest frequencies and thus the radio signatures closest to the source region. All the selected impulsive solar electron events have been found to be associated with an interplanetary type III burst. This allows to time the particle events at the 2 MHz plasma level and identify the associated coronal radio emissions. Except for 5 out of 27 cases, the electron events were found to be associated with a coronal type III burst in the metric wavelength range. The start frequency yields a lower limit to the density in the acceleration region. We also search for narrow-band spikes at the start of the type III bursts. In about half of the observed cases we find metric spikes or enhancements of type I bursts associated with the start of the electron event. If interpreted as the plasma emission of the acceleration process, the observed average frequency of spikes suggests a source density of the order of 3x10(8) cm(-3) consistent with the energy cut-off observed. C1 ETH Zentrum, Inst Astron, CH-8092 Zurich, Switzerland. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NIRFI, Radiophys Res Inst, Nizhnii Novgorod, Russia. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Benz, AO (reprint author), ETH Zentrum, Inst Astron, CH-8092 Zurich, Switzerland. NR 27 TC 11 Z9 11 U1 1 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PY 2001 VL 203 IS 1 BP 131 EP 144 DI 10.1023/A:1012725610185 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492MR UT WOS:000172172600010 ER PT J AU Gopalswamy, N St Cyr, OC Kaiser, ML Yashiro, S AF Gopalswamy, N St Cyr, OC Kaiser, ML Yashiro, S TI X-ray ejecta, white-light CMEs and a coronal shock wave SO SOLAR PHYSICS LA English DT Article ID WIND SPACECRAFT DATA; MASS EJECTIONS; INTERPLANETARY SHOCKS; RADIO EVIDENCE; SOLAR CORONA; II BURSTS; ORIGIN; PROMINENCES; TRANSIENT; LASCO AB We report on a coronal shock wave inferred from the metric type II burst of 13 January 1996. To identify the shock driver, we examined mass motions in the form of X-ray ejecta and white-light coronal mass ejections (CMEs). None of the ejections could be considered fast (> 400 km s(-1)) events. In white light, two CMEs occurred in quick succession, with the first one associated with X-ray ejecta near the solar surface. The second CME started at an unusually large height in the corona and carried a dark void in it. The first CME decelerated and stalled while the second one accelerated, both in the coronagraph field of view. We identify the X-ray ejecta to be the driver of the coronal shock inferred from metric type II burst. The shock speed reported in the Solar Geophysical Data (1000-2000 km s(-1)) seems to be extremely large compared to the speeds inferred from X-ray and white-light observations. We suggest that the MHD fast-mode speed in the inner corona could be low enough that the X-ray ejecta is supermagnetosonic and hence can drive a shock to produce the type II burst. C1 Catholic Univ Amer, Ctr Solar Phys & Space Weather, Washington, DC 20064 USA. Computat Phys Inc, Springfield, VA USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gopalswamy, N (reprint author), Catholic Univ Amer, Ctr Solar Phys & Space Weather, Washington, DC 20064 USA. RI Gopalswamy, Nat/D-3659-2012 NR 34 TC 12 Z9 12 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PY 2001 VL 203 IS 1 BP 149 EP 163 DI 10.1023/A:1012709903164 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492MR UT WOS:000172172600012 ER PT J AU Lawrence, JK Cadavid, AC Ruzmaikin, A AF Lawrence, JK Cadavid, AC Ruzmaikin, A TI Mesogranulation and turbulence in photospheric flows SO SOLAR PHYSICS LA English DT Article ID SOLAR CONVECTION; POWER SPECTRA; SCALE AB Below the scale of supergranules we find that cellular flows are present in the solar photosphere at two distinct size scales, approximately 2 Mm and 4 Mm, with distinct characteristic times. Simultaneously present in the flow is a non-cellular component, with turbulent scaling properties and containing 30% of the flow energy. These results are obtained by means of wavelet spectral analysis and modeling of vertical photospheric motions in a 2-hour sequence of 120 SOHO/MDI, high-resolution, Doppler images near disk center. The wavelets permit detection of specific local flow patterns corresponding to convection cells. C1 Calif State Univ Northridge, Dept Phys & Astron, Northridge, CA 91330 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lawrence, JK (reprint author), Calif State Univ Northridge, Dept Phys & Astron, Northridge, CA 91330 USA. NR 20 TC 13 Z9 13 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PY 2001 VL 202 IS 1 BP 27 EP 39 DI 10.1023/A:1011813925550 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DR UT WOS:000170968700003 ER PT J AU Auchere, F Hassler, DM Slater, DC Woods, TN AF Auchere, F Hassler, DM Slater, DC Woods, TN TI SWRI/LASP sounding rocket inter-calibration with the EIT instrument on board SOHO SO SOLAR PHYSICS LA English DT Article ID ULTRAVIOLET IMAGING TELESCOPE; MISSION AB Two successful sounding rocket flights were launched on 15 May 1997 and 2 November 1998 with an objective of providing inter-calibration with several of the instruments on board SOHO and TRACE. We will discuss here the results of the inter-calibration between the SwRI/LASP rocket imaging instruments and the Extreme-ultraviolet Imaging Telescope (EIT) on SOHO. The Multiple XUV Imager (MXUVI) sounding rocket instrument is a multi-layer mirror telescope equipped with an internal occulter and light trap to provide full-disk images of Fe IX/X 17.1 nm and off-limb observations of He II 30.4 nm. The SOHO/EIT instrument is also a full-disk multi-layer imager with four channels, Fe IX/X 17.1 nm, Fe XII 19.5 nm, Fe XV 28.4 nm and He II 30.4 nm. By comparison with the EIT observations taken at the same time, we provide new flat-field determinations for EIT which help quantify the sensitivity degradation of the EIT detector, as well as provide a measure of the off-limb stray-light characteristics of the two instruments. We find that the EIT stray-light function is strongly asymmetric, with greater stray light in the 17.1 and 19.5 nm quadrants than the 30.4 and 28.4 nm quadrants. Two possible causes of this asymmetry are the polishing processes of the EIT mirrors and the asymmetric support grid pattern in the foil mesh at the EIT pupil. C1 NASA, Goddard Space Flight Ctr, USRA, Greenbelt, MD 20771 USA. SW Res Inst, Boulder, CO 80302 USA. Univ Colorado, LASP, Boulder, CO 80307 USA. RP Auchere, F (reprint author), NASA, Goddard Space Flight Ctr, USRA, Code 682-3,Bldg 26,Room G-1, Greenbelt, MD 20771 USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PY 2001 VL 202 IS 2 BP 269 EP 280 DI 10.1023/A:1012237825048 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 486KG UT WOS:000171816500005 ER PT J AU Engvold, O Jakobsson, H Tandberg-Hanssen, E Gurman, JB Moses, D AF Engvold, O Jakobsson, H Tandberg-Hanssen, E Gurman, JB Moses, D TI On the nature of prominence absorption and emission in highly ionized iron and in neutral hydrogen SO SOLAR PHYSICS LA English DT Article ID TELESCOPE; EUV AB We have studied the behavior of the emission in the highly ionized EUV lines Fe IX/X, 171 Angstrom, Fe XII, 195 Angstrom, and Fe XV, 284 Angstrom observed in quiescent prominences. Kucera, Andretta, and Poland (1998) have explained the absorption of other highly ionized metallic EUV lines as due to absorption in the hydrogen continuum. However, since the authors noticed deviations from the expected lambda (3) dependence of the absorption strengths, we have explored the possibility that emission in EUV iron lines can influence the observations. We propose the existence of a hot, i.e., million-degree plasma component of the prominence-corona transition region (PCTR), where the EUV iron lines originate. We find that (i) neither of the two scenarios alone reproduces observations; (ii) both emission and absorption increase prior to eruption; (iii) the measurements of Kucera, Andretta, and Poland's 14 May event are strongly affected by hot PCTR emission. C1 Univ Oslo, Inst Theoret Astrophys, Oslo, Norway. Univ Alabama, CSPAR, Huntsville, AL 35899 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. USN, Res Lab, Washington, DC 20375 USA. RP Engvold, O (reprint author), Univ Oslo, Inst Theoret Astrophys, POB 1029, Oslo, Norway. NR 11 TC 31 Z9 31 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PY 2001 VL 202 IS 2 BP 293 EP 308 DI 10.1023/A:1012285218862 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 486KG UT WOS:000171816500007 ER PT J AU Harik, VM AF Harik, VM TI Ranges of applicability for the continuum beam model in the mechanics of carbon nanotubes and nanorods SO SOLID STATE COMMUNICATIONS LA English DT Article DE nanostructures; elasticity; mechanical properties AB Limitations in the validity of the continuum beam model for carbon nanotubes (NTs) and nanorods are examined. Applicability of all assumptions used in the model is restricted by the two criteria for geometric parameters that characterize the structure of NTs. The key non-dimensional parameters that control the NT buckling behavior are derived via dimensional analysis of the nanomechanical problem. A mechanical law of geometric similitude for NT buckling is extended from continuum mechanics for different molecular structures. A model applicability map, where two classes of beam-like NTs are identified, is constructed for distinct ranges of non-dimensional parameters. Expressions for the critical buckling loads and strains are tailored for two classes of NTs and compared with the data provided by the molecular dynamics simulations. (C) 2001 Elsevier Science Ltd. All ri-hts reserved. C1 NASA, Langley Res Ctr, ICASE, Hampton, VA 23681 USA. RP Harik, VM (reprint author), NASA, Langley Res Ctr, ICASE, MS 132C, Hampton, VA 23681 USA. NR 8 TC 82 Z9 84 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PY 2001 VL 120 IS 7-8 BP 331 EP 335 DI 10.1016/S0038-1098(01)00383-0 PG 5 WC Physics, Condensed Matter SC Physics GA 488AU UT WOS:000171912500016 ER PT J AU Buehrle, RD Fleming, GA Pappa, RS Grosveld, FW AF Buehrle, RD Fleming, GA Pappa, RS Grosveld, FW TI Finite element model development for aircraft fuselage structures SO SOUND AND VIBRATION LA English DT Article AB The ability to extend the valid frequency range for finite element based structural dynamic predictions using detailed models of the structural components and attachment interfaces is examined for several stiffened aircraft fuselage structures. This extended dynamic prediction capability is needed for the integration of mid-frequency noise control technology. Beam, plate and solid element models of the stiffener components are evaluated, Attachment models between the stiffener and panel skin range from a line along the rivets of the physical structure to a constraint over the entire contact surface. The finite element models are validated using experimental modal analysis results. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. Lockheed martin Engn & Sci, Hampton, VA USA. RP Buehrle, RD (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 8 TC 0 Z9 0 U1 1 U2 3 PU ACOUSTICAL PUBL INC PI BAY VILLAGE PA 27101 E OVIATT RD PO BOX 40416, BAY VILLAGE, OH 44140 USA SN 0038-1810 J9 SOUND VIB JI Sound Vib. PD JAN PY 2001 VL 35 IS 1 BP 32 EP 38 PG 7 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 399KC UT WOS:000166809300005 ER PT S AU Goldin, DS AF Goldin, DS BE Kondo, Y Sheffield, C Bruhweiler, FC TI Future space access and utilization SO SPACE ACCESS AND UTILIZATION BEYOND 2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT Symposium on Space Access and Utilization Beyond 2000 CY FEB 18, 2000 CL WASHINGTON, D.C. SP Amer Assoc Advancement Sci C1 NASA, Washington, DC 20546 USA. RP Goldin, DS (reprint author), NASA, Washington, DC 20546 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-475-3 J9 SCI TECH PY 2001 VL 101 BP 3 EP 5 PG 3 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BS03W UT WOS:000168410600001 ER PT S AU Mankins, JC AF Mankins, JC BE Kondo, Y Sheffield, C Bruhweiler, FC TI Technology strategies that may enable affordable human exploration and new space industries in the 21st century SO SPACE ACCESS AND UTILIZATION BEYOND 2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT Symposium on Space Access and Utilization Beyond 2000 CY FEB 18, 2000 CL WASHINGTON, D.C. SP Amer Assoc Advancement Sci C1 NASA, Off Space Flight, Adv Projects Off, Adv Concepts, Washington, DC 20546 USA. RP Mankins, JC (reprint author), NASA, Off Space Flight, Adv Projects Off, Adv Concepts, Washington, DC 20546 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-475-3 J9 SCI TECH PY 2001 VL 101 BP 59 EP 92 PG 34 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BS03W UT WOS:000168410600005 ER PT S AU Stone, EC AF Stone, EC BE Kondo, Y Sheffield, C Bruhweiler, FC TI Sampling the solar system SO SPACE ACCESS AND UTILIZATION BEYOND 2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT Symposium on Space Access and Utilization Beyond 2000 CY FEB 18, 2000 CL WASHINGTON, D.C. SP Amer Assoc Advancement Sci AB The Mariners, Pioneers, Voyagers, and Magellan missions gave us a global view of our diverse solar system. In the last five years, exploration has begun to shift from global to close-up views as we begin to sample these other worlds. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Stone, EC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-475-3 J9 SCI TECH PY 2001 VL 101 BP 93 EP 99 PG 7 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BS03W UT WOS:000168410600006 ER PT J AU Hsu, E Shopbell, PL Kadowaki, N Clark, G AF Hsu, E Shopbell, PL Kadowaki, N Clark, G TI Trans-Pacific Demonstrations (TPD): remote astronomy demonstration and results SO SPACE COMMUNICATIONS LA English DT Article AB In 1993, a proposal at the Japan-US Science, Technology, and Space Applications Program (JUSTSAP) workshop led to a subsequent series of satellite communications experiments and demonstrations, under the title of Trans-Pacific High Data Rate Satellite Communications Experiments. The first phase of this was a joint collaboration between government and industry teams in the United States and Japan that successfully demonstrated distributed high definition video (HDV) post-production on a global scale using a combination of high data rate satellites and terrestrial fiber optic asynchronous transfer mode (ATM) networks [1-3]. This was followed by the Phase-2 Internet Protocol (IP) based experiments and demonstrations [4-7] in tele-medicine and astronomical distance education, using another combination of two high data rate satellites and terrestrial fiber optic networks. This paper describes the Phase-2 remote astronomy experiment in detail. This experiment established a heterogeneous ground- and space-based network between Japan and several sites in the US, which was used by students, scientists, and educators to provide real-time interaction and collaboration with the 14-inch Telescopes in Education (TIE) telescope and associated data archive. The remote astronomy activity demonstrated collaborative observation and distance education at multiple locations around the globe and the transparent operations of distributed systems technologies over a combination of broadband satellites and terrestrial networks. The use of Internet Protocol related technologies allowed the general public to be an integral part of the exciting activities, helped to examine issues in constructing a global information infrastructure with broadband satellites, and afforded an opportunity to tap the research results from the (reliable) multicast and distributed systems communities. In this paper, we describe the network infrastructure at both the technical and user levels, review the operation of the experiment, and summarize our lessons learned. We find that such networking, while still somewhat complex to construct on highly distributed scales, can provide educators and students with a unique collaborative environment which greatly enhances the educational experience. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. IAI, Commun Res Lab, Tokyo 1848795, Japan. RP Hsu, E (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 19 TC 0 Z9 0 U1 0 U2 1 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 0924-8625 J9 SPACE COMMUN JI Space Commun. PY 2001 VL 17 IS 4 BP 279 EP 291 PG 13 WC Engineering, Aerospace; Telecommunications SC Engineering; Telecommunications GA 535CC UT WOS:000174626800004 ER PT J AU Kadowaki, N Yoshimura, N Nishinaga, N Gilstrap, R Foster, M AF Kadowaki, N Yoshimura, N Nishinaga, N Gilstrap, R Foster, M TI Trans-Pacific Demonstrations (TPD): network architecture, engineering and results SO SPACE COMMUNICATIONS LA English DT Article ID PERFORMANCE AB This paper presents the network architecture, engineering tests and their results for the Trans-Pacific Demonstrations (TPD). The experimental network was configured using an Intelsat satellite, N-STAR, and terrestrial networks in Japan, Canada and the United States. The TransPAC, submarine fiber-optic link was also used as a backup for the Intelsat link. We began to establish the full-scale experimental network in May 2000, and performed the engineering tests during about a two-month period of the TPD. We verified the connectivity of the satellite links, ATM connections, IP and higher layers, and then measured satellite link performance, ATM transmission performance, TCP/XTP performances and so on. As the result of the engineering test, we found that networks that include one or two satellite links can be used as network infrastructure for high data rate applications. C1 IAI, Commun Res Lab, Tokyo 1848795, Japan. NASA Res & Educ Network, Moffett Field, CA 94035 USA. RP Kadowaki, N (reprint author), IAI, Commun Res Lab, 4-2-1 Nukui Kita, Tokyo 1848795, Japan. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 0924-8625 J9 SPACE COMMUN JI Space Commun. PY 2001 VL 17 IS 4 BP 293 EP 302 PG 10 WC Engineering, Aerospace; Telecommunications SC Engineering; Telecommunications GA 535CC UT WOS:000174626800005 ER PT S AU Hebert, TJ Africano, JL Stansbery, EG Matney, MJ Hall, DT Pawlowski, JF Hanada, T Anz-Meador, PD Jarvis, KS Hartsough, N Mulrooney, MK AF Hebert, TJ Africano, JL Stansbery, EG Matney, MJ Hall, DT Pawlowski, JF Hanada, T Anz-Meador, PD Jarvis, KS Hartsough, N Mulrooney, MK BE Flury, W Klinkrad, H TI Optical observations of the orbital debris environment at NASA SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT B0 1/PEDAS1 Symposium of COSPAR Scientific Commission B held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP European Space Agcy, Int Acad Astronaut, Int Astronaut Federat, Int Astronaut Union, UN Off Outer Space Affair, Comm Space Res AB To monitor the orbital debris environment and facilitate orbital debris modeling and forecasting, the Orbital Debris Program Office of the NASA Johnson Space Center operates two principal telescopes: the liquid mirror telescope (LMT) and the charge coupled device debris telescope (CDT). Both telescopes are maintained at the NASA Cloudcroft Observatory, a 15-meter dome at 2761-meter elevation near Cloudcroft, NM. The LMT became operational in October 1996. Approximately 580 hours of digital video data from the LMT have been collected and processed by an automated hardware/software system. Results from 504 hours are presented. This paper also presents the results of a study of the detection sensitivity of the LMT system as well as a new measurement-based model for estimating object size from LMT measurements. The CDT, the other principal component of the optical program, became operational in November 1997. The CDT is currently being used in a statistical survey of catalogued and uncatalogued debris in geosynchronous earth orbit. Approximately 180 nights worth of data have been collected and results from a portion of this data are presented. A new direction for the CDT is to investigate various regions in GEO that would contain debris from hypothesized break-ups. Published by Elsevier Science Ltd on behalf of COSPAR. C1 Univ Houston, Dept Elect & Comp Engn, Houston, TX 77204 USA. Boeing N Amer, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Lockheed Martin Operat Co, Houston, TX 77058 USA. Hernandez Engn, Houston, TX USA. Kyushu Univ, Dept Aeronaut & Astronaut, Fukuoka 812, Japan. Viking Sci & Technol Inc, Houston, TX 77058 USA. Liberated Tech, Houston, TX 77058 USA. RP Hebert, TJ (reprint author), Univ Houston, Dept Elect & Comp Engn, Houston, TX 77204 USA. NR 10 TC 4 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 28 IS 9 BP 1283 EP 1290 DI 10.1016/S0273-1177(01)00398-2 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT60M UT WOS:000173496200004 ER PT S AU Johnson, NL Krisko, PH Liou, JC Anz-Meador, PD AF Johnson, NL Krisko, PH Liou, JC Anz-Meador, PD BE Flury, W Klinkrad, H TI NASA'S new breakup model of EVOLVE 4.0 SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT B0 1/PEDAS1 Symposium of COSPAR Scientific Commission B held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP European Space Agcy, Int Acad Astronaut, Int Astronaut Federat, Int Astronaut Union, UN Off Outer Space Affair, Comm Space Res AB Analyses of the fragmentation (due to explosions and collisions) of spacecraft and rocket bodies in low Earth orbit (LEO) have been performed this year at NASA/JSC. The overall goals of this study have been to achieve a better understanding of the results of fragmentations on the orbital debris environment and then to implement this understanding into the breakup model of EVOLVE 4.0. The previous breakup model implemented in EVOLVE 3.0 and other long-term orbital debris environment models was known to be inadequate in two major areas. First, it treated all fragmentational debris as spheres of a density which varied as a function of fragment diameter, where diameter was directly related to mass. Second, it underestimated the generation of fragments smaller than 10-cm in the majority of explosions. Without reliable data from both ground tests and on-orbit breakups, these inadequacies were unavoidable. Recent years, however, have brought additional data and related analyses: results of three ground tests, better on-orbit size and mass estimation techniques, more regular orbital tracking and reporting, additional radar resources dedicated to the observation of small objects, and simply a longer time period with which to observe the debris and their decay. Together these studies and data are applied to the reanalysis of the breakup model. In this paper we compare the new breakup model to the old break-up model in detail, including the size distributions for explosions and collisions, the area-to-mass and impact velocity assignments and distributions, and the delta-velocity distributions. These comparisons demonstrate a significantly better understanding of the fragmentation process as compared to previous versions of EVOLVE. C1 NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Off, Houston, TX 77058 USA. Lockheed Martin Space Operat, Houston, TX 77058 USA. Viking Sci & Technol Inc, Houston, TX 77058 USA. RP Johnson, NL (reprint author), NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Off, SN3, Houston, TX 77058 USA. NR 12 TC 105 Z9 118 U1 5 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 28 IS 9 BP 1377 EP 1384 DI 10.1016/S0273-1177(01)00423-9 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT60M UT WOS:000173496200015 ER PT S AU Krisko, PH Johnson, NL Opiela, JN AF Krisko, PH Johnson, NL Opiela, JN BE Flury, W Klinkrad, H TI EVOLVE 4.0 orbital debris mitigation studies SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT B0 1/PEDAS1 Symposium of COSPAR Scientific Commission B held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP European Space Agcy, Int Acad Astronaut, Int Astronaut Federat, Int Astronaut Union, UN Off Outer Space Affair, Comm Space Res AB In a continuing effort to limit future space debris generation, the NASA Policy Directive 8710.3 was issued in May 1997. It requires all NASA-sponsored programs to conduct formal assessments in accordance with NASA Safety Standard 1740.14 to quantify the potential to generate debris and to consider debris mitigation options. Recent improvements to the NASA long-term debris environment model, EVOLVE 4.0, allow for a reassessment of the effects of NASA Safety Standard mitigation measures on the projected debris environment. The NASA Safety Standard guidelines requiring the passivation of upper stages and spacecraft through depletion of on-board energy sources, and the post-mission disposal of satellites may be studied with EVOLVE 4.0. In this paper, we present the results of a set of parametric EVOLVE 4.0 studies. We set our test matrix to include a draconian level of explosion suppression, i.e., passivation in future launches, and post-mission disposal decay time periods ranging from 100 years to 25 years. The post-mission disposal options are initiated at a time 10 years in the future. It is confirmed that explosion suppression alone effects only a minor change in the long-term environment. Post-mission disposal implementation is required to significantly reduce it. But complications arise for the longer tested post-mission disposal lifetime. The enhanced dwell time at low altitudes (the dominant manned spacecraft region of Earth orbits) increases the likelihood that a collision will occur there compared to the lower post-mission disposal lifetime of 25 years. C1 Lockheed Martin Space Operat, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Orbital Debris Program Off, Houston, TX 77058 USA. RP Krisko, PH (reprint author), Lockheed Martin Space Operat, Houston, TX 77058 USA. NR 16 TC 4 Z9 4 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 28 IS 9 BP 1385 EP 1390 DI 10.1016/S0273-1177(01)00425-2 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT60M UT WOS:000173496200016 ER PT S AU Anz-Meador, PD Matney, MJ Liou, JC Johnson, NL AF Anz-Meador, PD Matney, MJ Liou, JC Johnson, NL BE Flury, W Klinkrad, H TI Updating the NASA debris engineering model: A review of source data and analytical techniques SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT B0 1/PEDAS1 Symposium of COSPAR Scientific Commission B held at the 33rd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP European Space Agcy, Int Acad Astronaut, Int Astronaut Federat, Int Astronaut Union, UN Off Outer Space Affair, Comm Space Res AB Orbital debris engineering models present a comprehensive view of the space environment to spacecraft designers and owners/operators. NASA is revising its orbital debris engineering model, ORDEM96, to incorporate approximately four years of new observations of the low Earth orbit (LEO) environment and new analytical methodologies. Since its last revision, significant measurements of the LEO environment have been made using radar and optical sensors (e.g. the Haystack and Haystack Auxiliary Radars and the Liquid Mirror Telescope) and returned surfaces (the Space Shuttle, the Hubble Space Telescope solar arrays, and the European Retrievable Carrier). This paper reviews the data sources and outlines analytical techniques used to reduce data to engineering quantities such as flux and directionality. Also, this paper describes one of the new analytical techniques-a method of building statistical distributions of orbit families. We use a Maximum Likelihood Estimator to take a given set of data and estimate the orbit populations that created that particular data set. This method precludes the ability to say whether a particular detected object is in a particular orbit, but it gives an overall picture of the debris families in orbit within the limits of the sampling error. C1 Viking Sci & Technol Inc, Houston, TX 77058 USA. Lockheed Martin Space Operat, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Anz-Meador, PD (reprint author), Viking Sci & Technol Inc, 16821 Buccaneer Lane,Ste 216, Houston, TX 77058 USA. NR 2 TC 0 Z9 0 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 28 IS 9 BP 1391 EP 1395 DI 10.1016/S0273-1177(01)00442-2 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT60M UT WOS:000173496200017 ER PT S AU Loftus, JP Johnson, NL AF Loftus, JP Johnson, NL BE Bendisch, J TI The current state of orbital debris mitigation standards in the United States SO SPACE DEBRIS 1999 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 32nd Symposium of the International-Academy-of-Astronautics on Safety, Rescue, and Quality in conjunction with the 50th International-Astronautical-Federation Congress CY OCT 04-08, 1999 CL AMSTERDAM, NETHERLANDS SP Amer Astronaut Soc, Int Acad Astronaut, Int Astronaut Federat AB Minimizing orbital debris generation has been United States national policy since February 1988, capping years of measurements and research by NASA and the Department of Defense. Today, orbital debris mitigation policies and standards in the U.S. have evolved and expanded to virtually all U.S. government space endeavors and a growing number of commercial programs as well. The current National Space Policy, signed by President Clinton in September 1996, not only directs the principal U.S. government agencies conducting space missions to minimize or reduce the accumulation of orbital debris but also recognizes the necessity of such practices by the international community. NASA Policy Directive 8710.3 (May 1997) has replaced Management Instruction 1700.8 (April 1993), and detailed orbital debris mitigation guidelines (NASA Safety Standard 1740.14, August 1995) are under revision. In the Department of Defense, orbital debris minimization and mitigation guidance are being formulated within the framework of U.S. Space Command Directives and Instructions. Separate instructions have also been issued by the component commands, e.g., U.S. Air Force Space Command. In 1997 both the Federal Aviation Administration. which licenses commercial space launches, and the National Oceanic and Atmospheric Administration, which licenses remote sensing spacecraft, issued notices of proposed rule making which included explicit passages addressing orbital debris mitigation. The Federal Communications Commission is also taking a more direct examination of orbital debris issues during its licensing of communications spacecraft. Since 1996, under the direction of the White House Office of Science and Technology Policy, a U.S. Government interagency working group on orbital debris has been developing recommended orbital debris mitigation standard practices for both government and industry. The first U.S. Government and industry workshop on orbital debris mitigation was held in January 1998. All of the above efforts support the U.S. Government promotion of responsible international debris mitigation measures, especially in the Inter-Agency Space Debris Coordination Committee and the Scientific and Technical Subcommittee of the United Nations' Committee on the Peaceful Uses of Outer Space. The special issue of the disposition of geosynchronous spacecraft is also addressed. Both the International Telecommunications Union and the Inter-Agency Space Debris Coordination Committee have made recommendations for the removal of spacecraft from the geostationary are at the end of mission. Most operators, however, have yet to accommodate their end-of-mission maneuvers to meet these criteria. NASA has been endeavoring to meet the recommendations but has encountered issues and difficulties which may also be experienced by other operators. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Johnson, NL (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-473-7 J9 SCI TECH PY 2001 VL 100 BP 157 EP 167 PG 11 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BS04R UT WOS:000168445500013 ER PT S AU Ahmed, M Burch, P Quinn, T AF Ahmed, M Burch, P Quinn, T BE Bendisch, J TI De-orbiting of the Compton Gamma Ray Observatory SO SPACE DEBRIS 2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 33rd Symposium on Safety, Rescue and Quality held in conjunction with the 51st International-Astronautical-Federation Congress CY OCT 02-06, 2000 CL RIO JANEIRO, BRAZIL SP Int Acad Astronaut AB After nine years of producing excellent science, the Compton Gamma Ray Observatory (CGRO) was successfully de-orbited into the Pacific Ocean on June 4, 2000. Even though the observatory was producing science when de-orbited, one of its three gyroscopes had failed, leaving no redundancy in the pointing control system of the spacecraft. The decision to de-orbit CGRO was made to minimize the risk to human life and property. Failure of another gyroscope would have caused the reentry to be uncontrollable. Therefore, NASA elected to de-orbit the observatory while it could still be directed to reenter in a selected area far away from any population. With human safety as the number one priority, the mission design and planning concentrated on optimizing all parameters to maximize the probability of mission success. Key aspects of the mission planning and execution consisted of the following: Debris Survival Analysis Debris Track Determination (assigning uncertainty margins) Reentry Location Selection Mission Design Parameters Probabilistic Risk Assessment Mission Execution Hazard Warning Notifications Contingency/Mishap Planning Collision Avoidance (with other space-borne assets) Public Affairs International Considerations Coordination with Other Organizations (Johnson Space Center, Jet Propulsion Lab, etc.) This paper summarizes the lessons learned during the planning and execution of the de-orbit mission and highlights important components of mission planning that must be considered carefully for future missions of this nature. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ahmed, M (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-485-0 J9 SCI TECH PY 2001 VL 103 BP 323 EP 330 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BS86F UT WOS:000171236700029 ER PT S AU Kern, VD Bhattacharya, S Bowman, RN Donovan, FM Elland, C Fahlen, TF Girten, B Kirven-Brooks, M Lagel, K Meeker, GB Santos, O AF Kern, VD Bhattacharya, S Bowman, RN Donovan, FM Elland, C Fahlen, TF Girten, B Kirven-Brooks, M Lagel, K Meeker, GB Santos, O BE Kiss, JZ Kern, VD TI Life sciences flight hardware development for the International Space Station SO SPACE LIFE SCIENCES: GRAVITY PERCEPTION AND TRANSDUCTION IN PLAN TS, FUNGI AND UNICELLULAR ORGANISMS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F1 1 Symposium of COSPAR Scientific Commission F held at 32nd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP natl Aeronut & Space Adm, Comm Space Res C1 NASA, Ames Res Ctr, Lockheed Martin Space Operat, Moffett Field, CA 94035 USA. RP Kern, VD (reprint author), NASA, Ames Res Ctr, Lockheed Martin Space Operat, POB 168, Moffett Field, CA 94035 USA. NR 7 TC 7 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 5 BP 1023 EP 1030 DI 10.1016/S0273-1177(01)00178-8 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT13V UT WOS:000172045600026 PM 11596633 ER PT S AU Sack, FD Schwuchow, JM Wagner, T Kern, V AF Sack, FD Schwuchow, JM Wagner, T Kern, V BE Kiss, JZ Kern, VD TI Gravity sensing in moss protonemata SO SPACE LIFE SCIENCES: GRAVITY PERCEPTION AND TRANSDUCTION IN PLANTS, FUNGI AND UNICELLULAR ORGANISMS SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT F1 1 Symposium of COSPAR Scientific Commission F held at 32nd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP NASA, Comm Space Res ID CERATODON-PURPUREUS; GRAVITROPISM; SEDIMENTATION; CELLS; TIP C1 Ohio State Univ, Dept Plant Biol, Columbus, OH 43210 USA. Duke Univ, Durham, NC 27708 USA. NASA, Ames Res Ctr, Lockheed Martin Space Operat, Moffett Field, CA 94035 USA. RP Sack, FD (reprint author), Ohio State Univ, Dept Plant Biol, 1735 Neil Ave, Columbus, OH 43210 USA. NR 21 TC 8 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES-SERIES PY 2001 VL 27 IS 5 BP 871 EP 876 DI 10.1016/S0273-1177(01)00151-X PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT13V UT WOS:000172045600003 PM 11594370 ER PT S AU Kern, VD Sack, FD AF Kern, VD Sack, FD BE Kiss, JZ Kern, VD TI Effects of spaceflight (STS-87) on tropisms and plastid positioning in protonemata of the moss Ceratodon purpureus SO SPACE LIFE SCIENCES: GRAVITY PERCEPTION AND TRANSDUCTION IN PLANTS, FUNGI AND UNICELLULAR ORGANISMS SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT F1 1 Symposium of COSPAR Scientific Commission F held at 32nd COSPAR Scientific Assembly CY JUL, 2000 CL WARSAW, POLAND SP NASA, Comm Space Res ID PHYSCOMITRELLA-PATENS; RED-LIGHT; WILD-TYPE; GRAVITROPISM; PHYTOCHROME; STATOLITHS; GRAVITY C1 Ohio State Univ, Dept Plant Biol, Columbus, OH 43210 USA. NASA, Ames Res Ctr, Lockheed Martin Space Operat, Moffett Field, CA 94035 USA. RP Kern, VD (reprint author), Ohio State Univ, Dept Plant Biol, 1735 Neil Ave, Columbus, OH 43210 USA. NR 21 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES-SERIES PY 2001 VL 27 IS 5 BP 941 EP 949 DI 10.1016/S0273-1177(01)00158-2 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BT13V UT WOS:000172045600012 PM 11596637 ER PT S AU Mvondo, DN Navarro-Gonzalez, R McKay, CP Coll, P Raulin, F AF Mvondo, DN Navarro-Gonzalez, R McKay, CP Coll, P Raulin, F BE Raulin, F Kobayashi, K Brack, A Greensberg, JM Hei, TK TI Production of nitrogen oxides by lightning and coronae discharges in simulated early earth, venus and mars environments SO SPACE LIFE SCIENCES: LIFE IN THE SOLAR SYSTEM: PREBIOTIC CHEMISTRY, CHIRALITY AND SPACE BIOLOGY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F3 4-2/F3 4-3/F2 4 Symposium of COSPAR Scientific Commission F held at the 32nd COSPAR Scientific Meeting CY JUL, 2000 CL WARSAW, POLAND SP Ctr Natk Etudes Spatiales, European Space Agcy, Int Soc Study Origin Life, Univ Paris 12, Comm Space Res, European Geophys Soc, Int Astonom Union, Agena Spaz Italiana, Inst Nazl Fis Nucl, Natl Aeronaut & Space Adm ID NOX PRODUCTION; NITRIC-OXIDE; FIELD-MEASUREMENTS; FIXATION; N2O; O-3; ATMOSPHERES; TITAN; RATES; AIR AB We present measurements for the production of nitrogen oxides (NO and N2O) in CO2-N-2 mixtures that simulate different stages of the evolution of the atmospheres of the Earth, Venus and Mars. The nitrogen fixation rates by two different types of electrical discharges, namely lightning and coronae, were studied over a wide range in CO2 and N-2 mixing ratios. Nitric oxide (NO) is formed with a maximum energy yield estimated to be similar to1.3x10(16) molecule J(-1) at 80% CO2 and similar to1.3x10(14) molecule J(-1) at 50% CO2 for lightning and coronae discharges, respectively. Nitrous oxide (N2O) is only formed by coronae discharge with a maximum energy yield estimated to be similar to1.2x10(13) molecule J(-1) at 50% CO2. The pronounced difference in NO production in lightning and coronae discharges and the lack of formation of N2O in lightning indicate that the physics and chemistry involved in nitrogen fixation differs substantially in these two forms of electric energy. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Natl Autonomous Univ Mexico, Inst Ciencias Nucl, Lab Quim Plasmas & Estudios Planetarios, Mexico City 04510, DF, Mexico. Univ Paris 12, Lab Interuniv Syst Atmospher, F-94010 Creteil, France. Univ Paris 07, F-94010 Creteil, France. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Mvondo, DN (reprint author), Natl Autonomous Univ Mexico, Inst Ciencias Nucl, Lab Quim Plasmas & Estudios Planetarios, Circuito Exter,Ciudad Univ,Apartado Postal 70-543, Mexico City 04510, DF, Mexico. RI Gonzalez, Rafael/D-1748-2009 NR 46 TC 13 Z9 13 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 2 BP 217 EP 223 PG 7 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS43Z UT WOS:000169859700006 PM 11605635 ER PT S AU Khare, BN Bakes, ELO Cruikshank, D McKay, CP AF Khare, BN Bakes, ELO Cruikshank, D McKay, CP BE Raulin, F Kobayashi, K Brack, A Greensberg, JM Hei, TK TI Solid organic matter in the atmosphere and on the surface of outer Solar System bodies SO SPACE LIFE SCIENCES: LIFE IN THE SOLAR SYSTEM: PREBIOTIC CHEMISTRY, CHIRALITY AND SPACE BIOLOGY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F3 4-2/F3 4-3/F2 4 Symposium of COSPAR Scientific Commission F held at the 32nd COSPAR Scientific Meeting CY JUL, 2000 CL WARSAW, POLAND SP Ctr Natk Etudes Spatiales, European Space Agcy, Int Soc Study Origin Life, Univ Paris 12, Comm Space Res, European Geophys Soc, Int Astonom Union, Agena Spaz Italiana, Inst Nazl Fis Nucl, Natl Aeronaut & Space Adm ID TITANS ATMOSPHERE; OPTICAL-PROPERTIES; CHEMISTRY; AEROSOLS; GAS; THOLINS; TEMPERATURE; HUYGENS; ORIGIN; N-2 C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Khare, BN (reprint author), NASA, Ames Res Ctr, MS 239-14, Moffett Field, CA 94035 USA. NR 49 TC 14 Z9 15 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 2 BP 299 EP 307 DI 10.1016/S0273-1177(01)00061-8 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS43Z UT WOS:000169859700016 PM 11605645 ER PT S AU Wu, HL Durante, M AF Wu, HL Durante, M BE Raulin, F Kobayashi, K Brack, A Greensberg, JM Hei, TK TI A biophysical model for estimating the frequency of radiation-induced mutations resulting from chromosomal translocations SO SPACE LIFE SCIENCES: LIFE IN THE SOLAR SYSTEM: PREBIOTIC CHEMISTRY, CHIRALITY AND SPACE BIOLOGY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F3 4-2/F3 4-3/F2 4 Symposium of COSPAR Scientific Commission F held at the 32nd COSPAR Scientific Meeting CY JUL, 2000 CL WARSAW, POLAND SP Ctr Natk Etudes Spatiales, European Space Agcy, Int Soc Study Origin Life, Univ Paris 12, Comm Space Res, European Geophys Soc, Int Astonom Union, Agena Spaz Italiana, Inst Nazl Fis Nucl, Natl Aeronaut & Space Adm ID HUMAN HPRT GENE; IONIZING-RADIATION; ABERRATIONS; BREAKS; REPAIR; CELLS AB Gene mutations can be induced by radiation as a result of chromosomal translocations. A biophysical model is developed to estimate the frequency of this type of mutation induced by low-LET radiation. Mutations resulting from translocations are assumed to be formed by misrejoining of two DNA double strand breaks (DSB), one within the gene and one on a different chromosome. The chromosome containing the gene is assumed to occupy a spherical territory and does not overlap spatially with other chromosomes. Misrejoining between two DSB can occur only if the two DSB are closer than an interaction distance at the time of their induction. Applying the model to mutations of the hprt gene induced in CO human lymphocyte cells by low-LET radiation, it is calculated that mutations resulting from translocations account for about 14% of the total mutations. The value of the interaction distance is determined to be 0.6 mum by comparing with the observed frequency of translocations in the X-chromosome. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, Kelsey Seybold Clin, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. Univ Naples Federico II, Dept Phys, Naples, Italy. RP Wu, HL (reprint author), NASA, Lyndon B Johnson Space Ctr, Kelsey Seybold Clin, Mail Code SD23, Houston, TX 77058 USA. RI Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 17 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 2 BP 361 EP 367 DI 10.1016/S0273-1177(01)00003-5 PG 7 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS43Z UT WOS:000169859700023 PM 11642298 ER PT S AU Kawata, T Durante, M Furusawa, Y George, K Ito, H Wu, H Cucinotta, FA AF Kawata, T Durante, M Furusawa, Y George, K Ito, H Wu, H Cucinotta, FA BE Raulin, F Kobayashi, K Brack, A Greensberg, JM Hei, TK TI G2-chromosome aberrations induced by high-LET radiations SO SPACE LIFE SCIENCES: LIFE IN THE SOLAR SYSTEM: PREBIOTIC CHEMISTRY, CHIRALITY AND SPACE BIOLOGY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F3 4-2/F3 4-3/F2 4 Symposium of COSPAR Scientific Commission F held at the 32nd COSPAR Scientific Meeting CY JUL, 2000 CL WARSAW, POLAND SP Ctr Natk Etudes Spatiales, European Space Agcy, Int Soc Study Origin Life, Univ Paris 12, Comm Space Res, European Geophys Soc, Int Astonom Union, Agena Spaz Italiana, Inst Nazl Fis Nucl, Natl Aeronaut & Space Adm ID PREMATURE CHROMOSOME CONDENSATION; HUMAN INTERPHASE CHROMOSOMES; ACCELERATED HEAVY-IONS; ALPHA-PARTICLES; CHARGED-PARTICLES; HUMAN FIBROBLASTS; MAMMALIAN-CELLS; MUTATION-INDUCTION; 10T1/2 CELLS; DAMAGE AB We report measurements of initial G2-chromatid breaks in normal human fibroblasts exposed to various types of high-LET particles. Exponentially growing AG 1522 cells were exposed to gamma -rays or heavy ions. Chromosomes were prematurely condensed by calyculin A. Chromatid-type breaks and isochromatid-type breaks were scored separately. The dose response curves for the induction of total chromatid breaks (chromatid-type + isochromatid-type) and chromatid-type breaks were linear for each type of radiation. However, dose response curves for the induction of isochromatid-type breaks were linear for high-LET radiations and linear-quadratic for gamma -rays. Relative biological effectiveness (RBE), calculated from total breaks, showed a LET dependent tendency with a peak at 55 keV/mum silicon (2.7) or 80 keV/mum carbon (2.7) and then decreased with LET (1.5 at 440 keV/mum). RBE for chromatid-type break peaked at 55 keV/mum (2.4) then decreased rapidly with LET. The RBE of 440 keV/mum iron particles was 0.7. The RBE calculated from induction of isochromatid-type breaks was much higher for high-LET radiations. It is concluded that the increased production of isochromatid-type breaks, induced by the densely ionizing track structure, is a signature of high-LET radiation exposure. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. Univ Space Res Assoc, Houston, TX USA. Univ Naples Federico II, Dept Phys, Naples, Italy. Natl Inst Radiol Sci, Int Space Radiat Lab, Chiba 260, Japan. Wyle Labs, Houston, TX USA. Chiba Univ, Dept Radiol, Chiba 260, Japan. Kelsey Seybold Clin, Houston, TX USA. RP Kawata, T (reprint author), NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. RI Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 33 TC 8 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 2 BP 383 EP 391 DI 10.1016/S0273-1177(01)00006-0 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS43Z UT WOS:000169859700025 PM 11642300 ER PT S AU Gonda, SR Wu, H Pingerelli, PL Glickman, BW AF Gonda, SR Wu, H Pingerelli, PL Glickman, BW BE Raulin, F Kobayashi, K Brack, A Greensberg, JM Hei, TK TI Three-dimensional transgenic cell model to quantify genotoxic effects of space environment SO SPACE LIFE SCIENCES: LIFE IN THE SOLAR SYSTEM: PREBIOTIC CHEMISTRY, CHIRALITY AND SPACE BIOLOGY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F3 4-2/F3 4-3/F2 4 Symposium of COSPAR Scientific Commission F held at the 32nd COSPAR Scientific Meeting CY JUL, 2000 CL WARSAW, POLAND SP Ctr Natk Etudes Spatiales, European Space Agcy, Int Soc Study Origin Life, Univ Paris 12, Comm Space Res, European Geophys Soc, Int Astonom Union, Agena Spaz Italiana, Inst Nazl Fis Nucl, Natl Aeronaut & Space Adm ID SIMULATED MICROGRAVITY; ASSAY; COCULTURE; MUTATIONS; RADIATION; SPECTRA; SYSTEMS; GROWTH; LINE; MICE AB In this paper we describe a three-dimensional, multicellular tissue-equivalent model, produced in NASA-designed, rotating wall bioreactors using mammalian cells engineered for genomic containment of multiple copies of defined target genes for genotoxic assessment. Rat 2 lambda fibroblasts, genetically engineered to contain high-density target genes for mutagenesis (Stratagene, Inc., Austin, TX), were cocultured with human epithelial cells on Cytodex beads in the High Aspect Ratio Bioreactor (Synthecon, Inc, Houston, TX). Multi-bead aggregates were formed by day 5 following the complete covering of the beads by fibroblasts. Cellular retraction occurred 8-14 days after coculture initiation culminating in spheroids retaining few or no beads. Analysis of the resulting tissue assemblies revealed: multicellular spheroids, fibroblasts synthesized collagen, and cell viability was retained for the 30-day test period after removal from the bioreactor. Quantification of mutation at the Lad gene in Rat 2 lambda fibroblasts in spheroids exposed to 0-2 Gy neon using the Big Blue color assay (Stratagene, Inc.), revealed a linear dose-response for mutation induction. Limited sequencing analysis of mutant clones from 0.25 or 1 Gy exposures revealed a higher frequency of deletions and multiple base sequencing changes with increasing dose. These results suggest that the three-dimensional, multicellular tissue assembly model produced in NASA bioreactors are applicable to a wide variety of studies involving the quantification and identification of genotocity including measurement of the inherent damage incurred in Space. Published by Elsevier Science Ltd on behalf of COSPAR. C1 NASA, Lyndon B Johnson Space Ctr, Biotechnol Program, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Seybold Clin, Houston, TX 77058 USA. Stratagene Inc, Cell Biol & Toxicol, Austin, TX 78612 USA. Univ Victoria, Ctr Environm Hlth, Victoria, BC V8W 2Y2, Canada. RP Gonda, SR (reprint author), NASA, Lyndon B Johnson Space Ctr, Biotechnol Program, 2101 NASA Rd 1, Houston, TX 77058 USA. NR 27 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 27 IS 2 BP 421 EP 430 DI 10.1016/S0273-1177(01)00010-2 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS43Z UT WOS:000169859700029 PM 11642304 ER PT S AU Newman, JS AF Newman, JS BE Reid, MS Romero, M TI Process Based Mission Assurance SO SPACE SAFETY, RESCUE AND QUALITY 1999-2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 33rd Symposium on Safety, Rescue and Quality held in conjunction with the 51st International-Astronautical-Federation Congress CY OCT 02-06, 2000 CL RIO JANEIRO, BRAZIL SP Int Acad Astronaut AB This paper presents a model for management of mission success in complex high technology programs. Process Based Mission Assurance (PBMA) is defined as implementing those management and systems engineering processes necessary to manage inherent aerospace program risks and maximize the likelihood of mission success. The PBMA model is derived from extensive benchmarking of "best practices" in aerospace, electronics, and automotive manufacturing, reinforced by "empirical evidence" derived from evaluation of selected NASA programs. The model has been developed to be consistent with U.S. government perform anc e-based contracting initiatives. The model provides a framework of high-level government expectations or "whats," within which contractors have the flexibility to identify and implement their own process "hows." The paper develops the hypothesis that regardless of contract form or procurement type, complex and demanding aerospace projects require a minimum set of processes necessary to assure safety, manage inherent aerospace pro,gram risks and maximize the likelihood of mission success. The paper develops the PBMA model centered on ten key elements, each element reflecting the themes of life-cycle risk management and defect/mishap prevention. The paper uses the PBMA template to evaluate a broad range of ongoing NASA initiatives, identifying the individual approaches deployed to manage risks and achieve mission success. C1 NASA, Washington, DC 20546 USA. RP Newman, JS (reprint author), NASA, Washington, DC 20546 USA. NR 6 TC 3 Z9 3 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-483-4 J9 SCI TECH PY 2001 VL 102 BP 3 EP 14 PG 12 WC Engineering, Aerospace SC Engineering GA BS86E UT WOS:000171236600001 ER PT S AU Greenfield, MA AF Greenfield, MA BE Reid, MS Romero, M TI Risk balancing profile tool SO SPACE SAFETY, RESCUE AND QUALITY 1999-2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 33rd Symposium on Safety, Rescue and Quality held in conjunction with the 51st International-Astronautical-Federation Congress CY OCT 02-06, 2000 CL RIO JANEIRO, BRAZIL SP Int Acad Astronaut C1 NASA, Washington, DC 20546 USA. RP Greenfield, MA (reprint author), NASA, Washington, DC 20546 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-483-4 J9 SCI TECH PY 2001 VL 102 BP 65 EP 71 PG 7 WC Engineering, Aerospace SC Engineering GA BS86E UT WOS:000171236600007 ER PT S AU Newman, JS AF Newman, JS BE Reid, MS Romero, M TI Failure-space: A systems engineering look at 50 space system failures SO SPACE SAFETY, RESCUE AND QUALITY 1999-2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 33rd Symposium on Safety, Rescue and Quality held in conjunction with the 51st International-Astronautical-Federation Congress CY OCT 02-06, 2000 CL RIO JANEIRO, BRAZIL SP Int Acad Astronaut AB Multiple perspectives are presented on failure-event-chain analysis and failure cause categorization followed by description of a systems engineering framework for failure evaluation. The framework consists of engineering and organizational elements typically within the program manager span of control. The systems engineering lens is then used to evaluate 50 space system failures. The high level mapping of failure attributes (causal root structure) indicates the need for across the board systems engineering rigor. That is, failure can propagate from virtually every critical activity in a space system life cycle. Analysis results show strong implication of design, design verification & test, manufacturing/production, and manufacturing/production verification & test as recurrent causal factors in space system failures. The Failure Space perspective reminds one of the need for thorough and complete risk management and assurance process implementation over the life of a project as well as, increased emphasis on lessons learned and recurrent monitoring of critical process fidelity. C1 NASA, Washington, DC 20546 USA. RP Newman, JS (reprint author), NASA, Washington, DC 20546 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-483-4 J9 SCI TECH PY 2001 VL 102 BP 103 EP 118 PG 16 WC Engineering, Aerospace SC Engineering GA BS86E UT WOS:000171236600011 ER PT S AU Greenfield, MA AF Greenfield, MA BE Reid, MS Romero, M TI NASA's use of quantitative risk assessment for safety upgrades SO SPACE SAFETY, RESCUE AND QUALITY 1999-2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 33rd Symposium on Safety, Rescue and Quality held in conjunction with the 51st International-Astronautical-Federation Congress CY OCT 02-06, 2000 CL RIO JANEIRO, BRAZIL SP Int Acad Astronaut AB Assured human space transportation is critical to the success of the U.S. space program. Today, the Space Shuttle serves as the primary vehicle for U.S. human space flight, and it has been designated as the fundamental space transportation system for U.S. participation in the assembly and maintenance of the International Space Station (ISS). NASA will continue to rely on the Space Shuttle until a replacement vehicle is complete and operational. Each Shuttle Orbiter was designed for a service life of 100 missions. This service life will extend well into the 21st century. Ensuring Space Shuttle continued success requires periodic maintenance and systems upgrades to improve safety, meet the manifest, improve supportability and avoid obsolescence, and lower cost to orbit. NASA's goal is to identify, prioritize, and implement the system upgrades that provide the greatest return and mitigation of risk. Quantitative risk assessment is a powerful tool to support decision-making in this regard. C1 NASA, Washington, DC 20546 USA. RP Greenfield, MA (reprint author), NASA, Washington, DC 20546 USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-483-4 J9 SCI TECH PY 2001 VL 102 BP 153 EP 159 PG 7 WC Engineering, Aerospace SC Engineering GA BS86E UT WOS:000171236600015 ER PT S AU Diaz, AV AF Diaz, AV BE Reid, MS Romero, M TI "Living With A Star - The NASA space weather initiative" SO SPACE SAFETY, RESCUE AND QUALITY 1999-2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 33rd Symposium on Safety, Rescue and Quality held in conjunction with the 51st International-Astronautical-Federation Congress CY OCT 02-06, 2000 CL RIO JANEIRO, BRAZIL SP Int Acad Astronaut AB Solar variability affects advanced technology, humans in space, and terrestrial climate. The sphere of the human environment continues to expand above and beyond our planet and we look to an increasing dependence on space-based systems and a permanent presence of humans in low Earth orbit and outward into the solar system. Specifically, improved space weather information is needed to address issues such as; human radiation exposure in space and during high altitude atmospheric flight; the radiation tolerance of technologies used in terrestrial and space communications and navigation systems as well as solar-drivers of near- and long-term climate change for the Earth. The goal of NASA's Living With A Star (LWS) Initiative is to lay the scientific foundation necessary for the development of a national policy and inter-agency response to space weather. An initial aim is the clear specification of the behavior of the coupled Earth-Sun system. With this system's specification an attempt will be made to identify the critical physical processes that dominate the system; an activity which leads to the development of an accurate predictive capability. The NASA LWS Initiative, led and directed by NASA Headquarters Office of Space Science with the Goddard Space Flight Center as the Lead Center for Program Management, will focus upon those aspects of the connected Sun-Earth system that directly affect life and society. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Diaz, AV (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-483-4 J9 SCI TECH PY 2001 VL 102 BP 201 EP 211 PG 11 WC Engineering, Aerospace SC Engineering GA BS86E UT WOS:000171236600019 ER PT S AU Curtis, SA Oberright, J Barth, J Folta, D Johnson, N AF Curtis, SA Oberright, J Barth, J Folta, D Johnson, N BE Reid, MS Romero, M TI Next generation mapping of the Earth's radiation environment: The radiation and technology development (RTD) mission SO SPACE SAFETY, RESCUE AND QUALITY 1999-2000 SE SCIENCE AND TECHNOLOGY SERIES LA English DT Proceedings Paper CT 33rd Symposium on Safety, Rescue and Quality held in conjunction with the 51st International-Astronautical-Federation Congress CY OCT 02-06, 2000 CL RIO JANEIRO, BRAZIL SP Int Acad Astronaut AB The lack of low latitude measurements of the terrestrial radiation environment between low and geosynchronous Earth orbit has been a major limitation in our ability to quantitatively predict the dosage levels for both piloted and robotic vehicles. A planned mission by NASA's office of the Human Exploration and Development of Space (HEDS) will allow the placement of about 8 identical near nanospacecraft in orbits between LEO and GEO. Outfitted with energetic particle detectors and magnetometers, these RTD spacecraft will allow us to study for the first time the space-time structure of the terrestrial radiation environment. The implications for model improvements and associated risk reduction and safety enhancement are discussed. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Curtis, SA (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 0278-4017 BN 0-87703-483-4 J9 SCI TECH PY 2001 VL 102 BP 243 EP 250 PG 8 WC Engineering, Aerospace SC Engineering GA BS86E UT WOS:000171236600023 ER PT J AU Pfaff, R Carlson, C Watzin, J Everett, D Gruner, T AF Pfaff, R Carlson, C Watzin, J Everett, D Gruner, T TI An overview of the Fast Auroral Snapshot (FAST) satellite SO SPACE SCIENCE REVIEWS LA English DT Review AB The FAST satellite is a highly sophisticated scientific satellite designed to carry out in situ measurements of acceleration physics and related plasma processes associated with the Earth's aurora. Initiated and conceptualized by scientists at the University of California at Berkeley, this satellite is the second of NASA's Small Explorer Satellite program designed to carry out small, highly focused, scientific investigations. FAST was launched on August 21, 1996 into a high inclination (83 degrees) elliptical orbit with apogee and perigee altitudes of 4175 km and 350 km, respectively. The spacecraft design was tailored to take high-resolution data samples (or `snapshots') only while it crosses the auroral zones, which are latitudinally narrow sectors that encircle the polar regions of the Earth. The scientific instruments include energetic electron and ion electrostatic analyzers, an energetic ion instrument that distinguishes ion mass, and vector DC and wave electric and magnetic field instruments. A state-of-the-art flight computer (or instrument data processing unit) includes programmable processors that trigger the burst data collection when interesting physical phenomena are encountered and stores these data in a 1 Gbit solid-state memory for telemetry to the Earth at later times. The spacecraft incorporates a light, efficient, and highly innovative design, which blends proven sub-system concepts with the overall scientific instrument and mission requirements. The result is a new breed of space physics mission that gathers unprecedented fields and particles observations that are continuous and uninterrupted by spin effects. In this and other ways, the FAST mission represents a dramatic advance over previous auroral satellites. This paper describes the overall FAST mission, including a discussion of the spacecraft design parameters and philosophy, the FAST orbit, instrument and data acquisition systems, and mission operations. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Pfaff, R (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Pfaff, Robert/F-5703-2012 OI Pfaff, Robert/0000-0002-4881-9715 NR 7 TC 28 Z9 29 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 98 IS 1-2 BP 1 EP 32 DI 10.1023/A:1013187826070 PG 32 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 500EA UT WOS:000172611900001 ER PT J AU Ergun, RE Carlson, CW Mozer, FS Delory, GT Temerin, M McFadden, JP Pankow, D Abiad, R Harvey, P Wilkes, R Primbsch, H Elphic, R Strangeway, R Pfaff, R Cattell, CA AF Ergun, RE Carlson, CW Mozer, FS Delory, GT Temerin, M McFadden, JP Pankow, D Abiad, R Harvey, P Wilkes, R Primbsch, H Elphic, R Strangeway, R Pfaff, R Cattell, CA TI The FAST satellite fields instrument SO SPACE SCIENCE REVIEWS LA English DT Review ID WAVE-PARTICLE CORRELATOR; PLASMA; MAGNETOSPHERE; DESIGN; GROWTH AB We describe the electric field sensors and electric and magnetic field signal processing on the FAST (Fast Auroral SnapshoT) satellite. The FAST satellite was designed to make high time resolution observations of particles and electromagnetic fields in the auroral zone to study small-scale plasma interactions in the auroral acceleration region. The DC and AC electric fields are measured with three-axis dipole antennas with 56 m, 8 m, and 5 m baselines. A three-axis flux-gate magnetometer measures the DC magnetic field and a three-axis search coil measures the AC magnetic field. A central signal processing system receives all signals from the electric and magnetic field sensors. Spectral coverage is from DC to similar to4 MHz. There are several types of processed data. Survey data are continuous over the auroral zone and have full-orbit coverage for fluxgate magnetometer data. Burst data include a few minutes of a selected region of the auroral zone at the highest time resolution. A subset of the burst data, high speed burst memory data, are waveform data at 2x10(6) sample s(-)1. Electric field and magnetic field data are primarily waveforms and power spectral density as a function of frequency and time. There are also various types of focused data processing, including cross-spectral analysis, fine-frequency plasma wave tracking, high-frequency polarity measurement, and wave-particle correlations. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Los Alamos Natl Lab, Los Alamos, NM USA. Univ Calif Los Angeles, Los Angeles, CA USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Minnesota, Minneapolis, MN USA. RP Ergun, RE (reprint author), Univ Colorado, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA. RI Pfaff, Robert/F-5703-2012; OI Pfaff, Robert/0000-0002-4881-9715; Cattell, Cynthia/0000-0002-3805-320X NR 14 TC 38 Z9 39 U1 1 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 98 IS 1-2 BP 67 EP 91 DI 10.1023/A:1013131708323 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 500EA UT WOS:000172611900003 ER PT J AU Habbal, SR Woo, R Vial, JC AF Habbal, SR Woo, R Vial, JC TI UVCS observations of velocity shear at streamer boundaries in the corona SO SPACE SCIENCE REVIEWS LA English DT Review ID SPECTROMETER; SOLAR AB Measurements of the intensities of the O VI 1032 and 1037 Angstrom spectral lines in the southern solar hemisphere, from 1.5 to 5 R-s, were made with the SOHO Ultraviolet Coronagraph Spectrometer (UVCS) in May 2000 close to solar maximum. The ratio of the intensity of the two oxygen lines is used as a proxy for solar wind velocity in the inner corona. White light images of the corona taken with the SOHO/LASCO-C2 during the same time period, and used to place the UVCS observations in the context of coronal structures, show streamers extending to high latitudes. The measured radial and azimuthal gradients of the intensity ratio reflect strong velocity shears in the corona with the slowest wind coinciding with the axis of streamers. Comparison of these results with ratios measured with UVCS during solar minimum indicates that the transition from fast to slow wind in the inner corona occurs within 20 degrees of the axis of streamers at both phases of the solar cycle. C1 Univ Wales, Aberystwyth SY23 3BZ, Dyfed, Wales. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Paris 11, Inst Astrophys Spatiale, CNRS, F-91405 Orsay, France. RP Univ Wales, Aberystwyth SY23 3BZ, Dyfed, Wales. EM shabbal@cfa.harvard.edu; richard.woo@jpl.nasa.gov; vial@ias.fr NR 6 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 5 EP 8 DI 10.1023/A:1011893104061 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700002 ER PT J AU Sittler, E Guhathakurta, M Skoug, R AF Sittler, E Guhathakurta, M Skoug, R TI Semi-empirical 2-D MHD model of the solar corona and solar wind: Energy flow in the corona SO SPACE SCIENCE REVIEWS LA English DT Review ID ELECTRONS AB We have developed a semi-empirical 2-D MHD model of the solar corona and solar wind for which the major data inputs are white light coronagraph data and plasma and magnetic field data from the Ulysses spacecraft. With regard to the white light coronagraph data we have used data from Spartan 201-05 to construct our empirical models of the electron density and magnetic field. We then use conservations laws of mass, momentum and energy to compute estimates of the flow velocity, effective temperature and effective heat flux as a function of radial distance and latitude. We will then compare our empirical model estimates with that of other theoretical models. An example, is the WKB contribution of Alfven waves to the effective temperature and effective heat flux. We have also investigated the importance of electron heat conduction in the context as past theoretical and empirical models and present a preliminary description of a semi-empirical model of electron heat conduction. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 39 EP 44 DI 10.1023/A:1011809707695 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700009 ER PT J AU Guhathakurta, M Sittler, E Fisher, R Kucera, T Gibson, S McComas, D Skoug, R AF Guhathakurta, M Sittler, E Fisher, R Kucera, T Gibson, S McComas, D Skoug, R TI Source region of high and low speed wind during the Spartan 201-05 flight SO SPACE SCIENCE REVIEWS LA English DT Review ID SOLAR CORONA; MODEL AB The large-scale coronal magnetic fields of the Sun are believed to play an important role in organizing the coronal plasma and channeling the high and low speed solar wind along the open magnetic field lines of the polar coronal holes and the rapidly diverging field lines close to the current sheet regions, as has been observed by the instruments aboard the Ulysses spacecraft from March 1992 to March 1997. We have performed a study of this phenomena within the framework of a semi-empirical model of the coronal expansion and solar wind using Spartan, SOHO, and Ulysses observations during the quiescent phase of the solar cycle. Key to this understanding is the demonstration that the white light coronagraph data can be used to trace out the topology of the coronal magnetic field and then using the Ulysses data to fix the strength of the surface magnetic field of the Sun. As a consequence, it is possible to utilize this semi-empirical model with remote sensing observation of the shape and density of the solar corona and in situ data of magnetic field and mass flux to predict values of the solar wind at all latitudes through out the solar system. We have applied this technique to the observations of Spartan 201-05 on 1-2 November, 1998, SOHO and Ulysses during the rising phase of this solar cycle and speculate on what solar wind velocities Ulysses will observe during its polar passes over the south and the north poles during September of 2000 and 2001. In order to do this the model has been generalized to include multiple streamer belts and co-located current sheets. The model shows some interesting new results. C1 SW Res Inst, NASA, Goddard Space Flight Ctr, San Antonio, TX 78284 USA. Los Alamos Natl Lab, San Antonio, TX USA. RP SW Res Inst, NASA, Goddard Space Flight Ctr, 6220 Culebra Rd, San Antonio, TX 78284 USA. RI Gibson, Sarah/A-9189-2011; Kucera, Therese/C-9558-2012 NR 5 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 45 EP 50 DI 10.1023/A:1011834413147 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700010 ER PT J AU Suess, S AF Suess, S TI Fine structure in the corona at high latitudes at solar maximum SO SPACE SCIENCE REVIEWS LA English DT Review ID WIND AB Microstreams and pressure balance structures in fast solar wind were more easily detected at Ulysses at 2.2 AU over the poles than at Helios at 0.3 AU. This is because solar rotation leads to dynamic interactions between different speed regimes at a rate that depends on latitude for the same size features. Dynamic interactions make structures more difficult to detect with increasing distance from the Sun. At solar maximum, Ulysses will sample high latitude solar wind coming from streamers, providing information on fine structure at the tops of streamers and on the source of slow solar wind. Examples are given here of the detectability of various sized structures at Ulysses when it is over the polar regions of the Sun. C1 NASA, George C Marshall Space Flight Ctr, SD50, Huntsville, AL 35812 USA. RP NASA, George C Marshall Space Flight Ctr, SD50, Huntsville, AL 35812 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 55 EP 58 DI 10.1023/A:1011813808604 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700012 ER PT J AU Suess, S Poletto, G AF Suess, S Poletto, G TI The Fall 2000 and Fall 2001 SOHO-Ulysses quadratures SO SPACE SCIENCE REVIEWS LA English DT Review AB SOHO-Ulysses quadrature occurs when their included angle with the Sun is 90 degrees. At these times the same plasma leaving the Sun in the direction of Ulysses can first be remotely analyzed with SOHO and then later be sampled in situ at Ulysses. Quadratures in Fall 2000/2001 are of special interest because Ulysses will be near the south and north heliographic poles, respectively, and it will be near sunspot maximum. But, the quadrature geometry is complex - Ulysses is not in a true polar orbit and the orbital speed of Ulysses and SOHO about the Sun will be comparable. In neither case is true quadrature achieved, but this works to the observer's advantage. Here we show plots of the relative positions of SOHO and Ulysses throughout the two quadrature intervals. C1 NASA, George C Marshall Space Flight Ctr, SD50, Huntsville, AL 35812 USA. Osserv Astrofis Arcetri, I-50125 Florence, Italy. RP NASA, George C Marshall Space Flight Ctr, SD50, Huntsville, AL 35812 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 59 EP 62 DI 10.1023/A:1011865825442 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700013 ER PT J AU Pauluhn, A Solanki, SK Schuhle, U Wilhelm, K Lang, J Thompson, WT Ruedi, I Hollandt, J Huber, MCE AF Pauluhn, A Solanki, SK Schuhle, U Wilhelm, K Lang, J Thompson, WT Ruedi, I Hollandt, J Huber, MCE TI Comparison of quiet-Sun radiances measured by CDS and SUMER on SOHO SO SPACE SCIENCE REVIEWS LA English DT Review AB Since the beginning of the SOHO (Solar and Heliospheric Observatory) mission an intercalibration programme was carried out which included simultaneous observations of the EUV instruments CDS (Coronal Diagnostic Spectrometer) and SUMER (Solar Ultraviolet Measurements of Emitted Radiation) of common targets on the quiet Sun. The observations in the chromospheric line of He i (584 Angstrom) and the two coronal lines of Mg x (609 Angstrom and 624 Angstrom) thus cover the long period of 4 years and provide a data set highly suitable not only for instrumental comparison but also for studies of the quiet Sun's long term variability. Up to the SOHO accident, both instruments show a very good temporal correlation and stability. Even after the loss and recovery of the spacecraft, when the instruments had been exposed to extreme temperature conditions, the performance of the CDS and SUMER instruments is still good, as is the temporal correlation. However, the ratio between the efficiencies of the two instruments, which remained constant with time until the SOHO accident seems to have changed afterwards. In the coronal lines both instruments show an increase of average radiances towards the solar maximum. C1 INTEC HTA Bern, Bern, Switzerland. Swiss Fed Inst Technol, Inst Astron, CH-8092 Zurich, Switzerland. Max Planck Inst Aeron, Katlenburg Lindau, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. NASA, Goddard Space Flight Ctr, Emergent Informat Technol Inc, Greenbelt, MD 20771 USA. PMOD WRC, Davos, Switzerland. Phys Tech Bundesanstalt, Berlin, Germany. ESA, ESTEC, Noordwijk, Netherlands. RP INTEC HTA Bern, Bern, Switzerland. EM pauluhn@issi.unibe.ch RI Thompson, William/D-7376-2012; Solanki, Sami/E-2487-2013; Hollandt, Jorg/A-2124-2014 OI Solanki, Sami/0000-0002-3418-8449; NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 63 EP 66 DI 10.1023/A:1011817909513 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700014 ER PT J AU Woo, R Habbal, SR AF Woo, R Habbal, SR TI Associating the solar wind measured by Ulysses with its source at the sun SO SPACE SCIENCE REVIEWS LA English DT Review ID POLAR CORONAL HOLE; INTERPLANETARY SPACE; PLASMA OBSERVATIONS; PHYSICAL-PROPERTIES; DENSITY STRUCTURE; SOURCE REGIONS; SLOW; STREAMERS AB Radio occultation, ultraviolet, and white-light measurements have expanded our knowledge of the morphology of density and velocity in polar coronal holes, and made it possible to carry out the first systematic comparisons between the Ulysses solar wind measurements and quantitative white-light observations of the solar corona. This paper summarizes the rationale and salient features of this new approach which has been used to relate the solar wind observed by Ulysses in 1993-1995 to the inner corona. The statistical characteristics (average, standard deviation, and autocorrelation function) of the Ulysses density measurements of the fast wind are found to be mirrored in those of polarized brightness measurements of path-integrated density made by the High Altitude Observatory (HAO) Mauna Loa K-coronagraph at 1.15 R-circle dot. These results reinforce the conclusions from comparisons between measurements of the outer and inner corona. They show that the polar coronal hole extends radially into the solar wind, and that sources of the fast wind are not limited to coronal holes. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Wales, Aberystwyth, Dyfed, Wales. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 27 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 81 EP 85 DI 10.1023/A:1011822010421 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700016 ER PT J AU Reiner, M AF Reiner, M TI Kilometric type III radio bursts, electron beams, and interplanetary density structures SO SPACE SCIENCE REVIEWS LA English DT Review ID MODEL INTERPRETATION; WIND SPACECRAFT; SOLAR-WIND; EMISSION; WAVES AB We briefly review kilometric type III radio bursts and what their physical characteristics reveal about the propagation and characteristics of suprathermal electron beams and about density structures in interplanetary medium. C1 Catholic Univ Amer, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Catholic Univ Amer, Greenbelt, MD 20771 USA. NR 15 TC 14 Z9 14 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 129 EP 139 DI 10.1023/A:1011894631803 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700023 ER PT J AU MacDowall, RJ Lin, NG McComas, DJ AF MacDowall, RJ Lin, NG McComas, DJ TI Langmuir wave activity: Comparing the Ulysses solar minimum and solar maximum orbits SO SPACE SCIENCE REVIEWS LA English DT Review ID MAGNETIC HOLES; PLASMA-WAVES; RADIO; WIND AB We examine the occurrence and intensity of Langmuir wave activity (electrostatic waves at the electron plasma frequency) during the solar minimum and solar maximum orbits of Ulysses. At high latitudes during the solar minimum orbit, occurrences of Langmuir waves in magnetic holes were frequent; in the second orbit, they were less common. This difference, in comparison with observations from the first Ulysses fast heliolatitude scan, suggests that Langmuir wave activity in magnetic holes is enhanced in solar wind from polar coronal holes. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SW Res Inst, San Antonio, TX 78228 USA. RP NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI MacDowall, Robert/D-2773-2012 NR 9 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 141 EP 146 DI 10.1023/A:1011846700852 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700024 ER PT J AU Balogh, A Smith, EJ AF Balogh, A Smith, EJ TI The heliospheric magnetic field at solar maximum: Ulysses observations SO SPACE SCIENCE REVIEWS LA English DT Review ID CURRENT SHEET; ALFVEN WAVES; WIND AB At solar maximum, the large-scale structure of the heliospheric magnetic field (HMF) reflects the complexity of the Sun's coronal magnetic fields. The corona is characterised by mostly closed magnetic structures and short-lived, small coronal holes. The axis of the Sun's dipole field is close to the solar equator; there are also important contributions from the higher order terms. This complex and variable coronal magnetic configuration leads to a much increased variability in the HMF on all time scales, at all latitudes. The transition from solar minimum to solar maximum conditions, as reflected in the HMF, is described, as observed by Ulysses during its passage to high southern heliolatitudes. The magnetic signatures associated with the interaction regions generated by short-lived fast solar wind streams are presented, together with the highly disordered period in mid-1999 when there was a considerable reorganisation in coronal structures. The magnetic sector structure at high heliolatitudes shows, from mid-1999, a recognisable two-sector structure, corresponding to a highly inclined Heliospheric Current Sheet. A preliminary investigation of the radial component of the magnetic field indicates that it remains, on average, constant as a function of heliolatitude. Intervals of highly Alfvenic fluctuations in the rarefaction regions trailing the interaction regions have been, even if intermittently, identified even close to solar maximum. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Prince Consort Rd, London SW7 2BZ, England. NR 17 TC 25 Z9 25 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 147 EP 160 DI 10.1023/A:1011854901760 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700025 ER PT J AU Forsyth, RJ Balogh, A Smith, EJ AF Forsyth, RJ Balogh, A Smith, EJ TI Latitudinal variation of the underlying heliospheric magnetic field direction: Comparison of the Ulysses first and second orbits SO SPACE SCIENCE REVIEWS LA English DT Review AB We discuss the underlying direction of the heliospheric magnetic field measured by Ulysses in the latitude range 6 degrees S-65 degrees S by examining distributions of the magnetic field azimuthal angle with respect to the simple Parker spiral model. During the first Ulysses traversal of this latitude range in 1992-1994, while solar activity was declining, the shape of the distributions obtained at high latitudes in the fast solar wind differed from that at lower latitudes. In the present data set, obtained during rising solar activity, both field polarities are present at all latitudes and the peaks of the distributions agree with the predicted spiral direction to first approximation. However, compared to the first orbit, a significantly greater percentage of the observed field vectors have large deviations from the spiral direction. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England. NR 6 TC 7 Z9 7 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 161 EP 164 DI 10.1023/A:1011859119507 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700026 ER PT J AU Lin, NG Kellogg, PJ MacDowall, RJ Gary, SP AF Lin, NG Kellogg, PJ MacDowall, RJ Gary, SP TI Ion acoustic waves in the heliosphere SO SPACE SCIENCE REVIEWS LA English DT Review ID SOLAR-WIND AB Observations of ion acoustic waves in the solar wind during the first and second orbit of the Ulysses spacecraft are presented. The observations show variations of the wave activity with the heliolatitude and with the phase of the solar cycle. The interrelationships between the wave intensity and the electron heat flux and the ratio of electron to proton temperature, T-e/T-p, are examined. C1 Univ Minnesota, Minneapolis, MN 55455 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Univ Minnesota, Minneapolis, MN 55455 USA. RI MacDowall, Robert/D-2773-2012 NR 5 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 193 EP 196 DI 10.1023/A:1011823505395 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700031 ER PT J AU Thejappa, G MacDowall, RJ AF Thejappa, G MacDowall, RJ TI In situ wave phenomena associated with magnetic clouds and other ejecta SO SPACE SCIENCE REVIEWS LA English DT Review ID CORONAL MASS EJECTIONS; SOLAR-WIND; ULYSSES AB We present Ulysses Unified Radio and Plasma Wave (URAP) observations of ion-acoustic waves associated with magnetic clouds and ejecta. The peak intensities of these waves, which usually occur inside CMEs when T-e/T(i)much greater than1, are not correlated with heliocentric distance or electron to ion temperature ratio inside the CMEs. C1 Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RI MacDowall, Robert/D-2773-2012 NR 9 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 211 EP 215 DI 10.1023/A:1011883724050 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700035 ER PT J AU Forsyth, RJ Rees, A Balogh, A Smith, EJ AF Forsyth, RJ Rees, A Balogh, A Smith, EJ TI Magnetic field observations of transient events at Ulysses, 1996-2000 SO SPACE SCIENCE REVIEWS LA English DT Review ID SOLAR-WIND; CLOUDS AB During the years 1996-2000 solar activity has been gradually rising and is now close to maximum. At the same time the Ulysses spacecraft has performed a north to south traverse of the low latitude regions of the heliosphere and is now once again travelling through high southerly latitudes. We show some examples and report on the occurence rates of transient solar wind disturbances which have been identified by their magnetic field signatures. 'Magnetic clouds' remain more common at low (compared to high) latitudes despite the rise in solar activity. However, more events were observed at high latitudes than at solar minimum. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England. NR 6 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 217 EP 220 DI 10.1023/A:1011835809029 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700036 ER PT J AU Moullard, O Marsden, RG Sanderson, TR Tranquille, C Forsyth, RJ Goldstein, BE AF Moullard, O Marsden, RG Sanderson, TR Tranquille, C Forsyth, RJ Goldstein, BE TI Energetic ions observed at low to high latitudes in the southern heliosphere during declining and rising solar activity SO SPACE SCIENCE REVIEWS LA English DT Review ID HIGH HELIOGRAPHIC LATITUDES; INTERACTION REGIONS; MAGNETIC-FIELD; ECLIPTIC-PLANE; ULYSSES; FLUXES AB We present and compare observations of energetic protons during the two first transits of the Ulysses spacecraft from low to high latitudes in the southern heliosphere. Protons in the energy range 1.8-3.8 MeV from the COSPIN experiment are studied for global trends and in relation to some ambient structures in the solar wind (corotating interaction region, forward/reverse shock). The global trends show the large dependence on the heliospheric condition and solar activity, including indications of a larger ambient particle population during the rising phase of solar activity and more efficient solar wind particle accelerators during the declining phase. More enhancements in the proton flux intensity are time associated with forward shocks than reverse contrary to first pass. Recurrent structures are found even during the second transit. Some latitude dependent periodicities are observed that could relate to the differential solar rotation. C1 ESA, ESTEC, Dept Space Sci, Noordwijk, Netherlands. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London, England. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP ESA, ESTEC, Dept Space Sci, Noordwijk, Netherlands. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 289 EP 292 DI 10.1023/A:1011885219024 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700050 ER PT J AU McDonald, FB Fujii, Z Ferrando, P Heber, B Raviart, A Kunow, H Lal, N Muller-Mellin, R Wibberenz, G McGuire, R Paizis, C AF McDonald, FB Fujii, Z Ferrando, P Heber, B Raviart, A Kunow, H Lal, N Muller-Mellin, R Wibberenz, G McGuire, R Paizis, C TI The onset of long term modulation in the heliosphere in cycle 23 SO SPACE SCIENCE REVIEWS LA English DT Review ID COSMIC-RAYS AB The combination of Voyager 1 (77.9 AU, 34.4 degrees N) and Voyager 2 (61.2 AU, 24.5 degrees S) at moderate heliolatitudes in the distant heliosphere and Ulysses with its unique latitudinal surveys in the inner heliosphere along with IMP 8 and other satellites at 1 AU constitutes a network of observatories that are ideally suited to study cosmic rays over the solar minimum of cycle 22 and the onset of solar activity and the long term cosmic ray modulation of cycle 23. Through 2000.7 there have been three well-defined step decreases in the cosmic ray intensity at 1 AU with the cumulative effect being in good agreement with the net decrease in cycle 21 at a comparable time in the solar cycle. Over this period the intensity changes at Ulysses are similar to those at 1 AU. In the distant heliosphere the initial decreases appear to be smaller than those at 1 AU. However the full effects of the interplanetary disturbances producing the most recent and largest step decrease in the inner heliosphere have not yet reached V-2. C1 Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. CE Saclay, Serv Astrophys, DAPNIA, DSM,CEA, Gif Sur Yvette, France. Nagoya Univ, Solar Terr Environm Lab, Chikusa Ku, Nagoya, Aichi, Japan. Univ Kiel, Inst Expt & Angew Phys, D-24098 Kiel, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Milan, Ist Fis Cosm, Milan, Italy. Max Planck Inst Aeron, D-37191 Katlenburg Duhm, Germany. RP Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 321 EP 325 DI 10.1023/A:1011841404003 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700053 ER PT J AU Wibberenz, G Cane, HV Richardson, IG Von Rosenvinge, TT AF Wibberenz, G Cane, HV Richardson, IG Von Rosenvinge, TT TI The influence of tilt angle and magnetic field variations on cosmic ray modulation SO SPACE SCIENCE REVIEWS LA English DT Review AB The maximum inclination of the heliospheric current sheet (the tilt angle) and the magnitude B of the heliospheric magnetic field are often used to characterize cosmic ray (CR) modulation. The relevance of B is likely to be the coupling of the interplanetary diffusion coefficients K to the field magnitude in a relation K proportional toB(-n). In this paper we study the coupled influence of tilt angle and magnetic field variations on the modulation of cosmic rays at neutron monitor energies for the 1974 mini-cycle and for the onsets of solar cycles 21, 22, and 23. It is suggested that for A >0 polarity epochs, the sensitivity of the CR response to variations in B is partly controlled by the size of the tilt angle, alpha. The onsets of cycles 21 and 23 exhibit differences, related to phase differences in these parameters. A simple model is used to predict the CR response to variations in B. C1 Univ Kiel, IEAP, D-24118 Kiel, Germany. NASA, LHEA, GSFC, Greenbelt, MD 20771 USA. RP Univ Kiel, IEAP, Olshaussenstr 40, D-24118 Kiel, Germany. OI Richardson, Ian/0000-0002-3855-3634 NR 6 TC 9 Z9 9 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 343 EP 347 DI 10.1023/A:1011849605820 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700057 ER PT J AU Wibberenz, G Ferreira, SES Potgieter, MS Cane, HV AF Wibberenz, G Ferreira, SES Potgieter, MS Cane, HV TI Time-dependent 2D model compared with observations during the 1974 mini cycle SO SPACE SCIENCE REVIEWS LA English DT Review ID COSMIC-RAYS; MODULATION AB The 1974 mini-cycle is a medium term cosmic ray modulation event with about one year duration. It occurred in an A >0 epoch of solar magnetic polarity during conditions of low activity, but with an increase in the latitudinal extent of the heliospheric current sheet (tilt angle alpha) and the magnitude B of the heliospheric magnetic field. This cosmic ray decrease can be used to test the hypothesis that such large scale decreases (mini cycles) may be caused primarily by a combination of changes in alpha and B. For this purpose a fully time-dependent 2D model of solar modulation is used, which includes the effects of global and current sheet drifts, and anisotropic perpendicular diffusion. Such models have been used successfully to describe the proton energy spectrum as well as the radial and latitudinal gradients near 1 AU. Comparison of the model solutions with the observed decrease for 1.8 GV protons allows us to study the combined influence of variable drift and diffusion effects throughout the event. C1 Univ Kiel, IEAP, D-24118 Kiel, Germany. Potchefstroom Univ Christian Higher Educ, Unit Space Phys, ZA-2520 Potchefstroom, South Africa. NASA, High Energy Astrophys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Univ Kiel, IEAP, Olshaussenstr 40, D-24118 Kiel, Germany. NR 10 TC 16 Z9 16 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 373 EP 376 DI 10.1023/A:1011862008546 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700063 ER PT J AU Robertson, IP Cravens, TE Snowden, S Linde, T AF Robertson, IP Cravens, TE Snowden, S Linde, T TI Temporal and spatial variations of heliospheric X-ray emissions associated with charge transfer of the solar wind with interstellar neutrals SO SPACE SCIENCE REVIEWS LA English DT Review ID COMET HYAKUTAKE; IONS AB A simple model has been developed that demonstrates that heliospheric X-ray emission can account for about 25%-50% of observed soft X-ray background intensities. Similar to cometary soft X-ray emission, these X-rays are thought to be produced in the heliosphere due to charge transfer collisions between heavy solar wind ions and interstellar neutrals. A more complex model has now been developed to take into account temporal and spatial variations of the solar wind and interstellar neutrals. Measured time histories of the solar wind proton flux are used in the model and the results are compared with the 'long-term enhancements' in the soft X-ray background measured by ROSAT for the same time period. C1 Univ Kansas, Lawrence, KS 66045 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Chicago, Chicago, IL 60637 USA. RP Univ Kansas, Lawrence, KS 66045 USA. RI Snowden, Steven/D-5292-2012 NR 7 TC 24 Z9 24 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2001 VL 97 IS 1-4 BP 401 EP 405 DI 10.1023/A:1011822327202 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 472DH UT WOS:000170967700068 ER PT J AU Ruzmaikin, A AF Ruzmaikin, A TI Origin of sunspots SO SPACE SCIENCE REVIEWS LA English DT Review ID SOLAR CONVECTION ZONE; BIPOLAR ACTIVE REGIONS; EMERGING FLUX TUBES; MAGNETIC-FLUX; ROTATION; MAGNETOCONVECTION; PATTERNS; INTERIOR; BUOYANCY; DYNAMOS AB Sunspots, seen as cool regions on the surface of the Sun, are a thermal phenomenon. Sunspots are always associated with bipolar magnetic loops that break through the solar surface. Thus to explain the origin of sunspots we have to understand how the magnetic field originates inside the Sun and emerges at its surface. The field predicted by mean-field dynamo theories is too weak by itself to emerge at the surface of the Sun. However, because of the turbulent character of solar convection the fields generated by dynamo are intermittent - i.e., concentrated into ropes or sheets with large spaces in between. The intermittent fields are sufficiently strong to be able to emerge at the solar surface, in spite of the fact that their mean (average) value is weak. It is suggested here that magnetic fields emerge at the solar surface at those random times and places when the total magnetic field (mean field plus fluctuations) exceeds the threshold for buoyancy. The clustering of coherently emerged loops results in the formation of a sunspot. A non-axisymmetric enhancement of the underlying magnetic field causes in the clustering of sunspots forming sunspot groups, clusters of activity and active longitudes. The mean field, which is not directly observable, is also important, being responsible for the ensemble regularities of sunspots, such as Hale's law of sunspot polarities and the 11-year periodicity. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ruzmaikin, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 42 TC 11 Z9 11 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD JAN PY 2001 VL 95 IS 1-2 BP 43 EP 53 DI 10.1023/A:1005290116078 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 391PU UT WOS:000166365000006 ER PT J AU Goodman, ML AF Goodman, ML TI The necessity of using realistic descriptions of transport processes in modeling the solar atmosphere, and the importance of understanding chromospheric heating SO SPACE SCIENCE REVIEWS LA English DT Review ID MAGNETIC-FLUX TUBES; LONGITUDINAL-TRANSVERSE WAVES; CONVECTIVE COLLAPSE; PLASMA TURBULENCE; BRIGHT POINTS; QUIET SUN; NETWORK; GRAINS; FIELDS; OSCILLATIONS AB Three points and research directions are discussed: The outstanding problem of identifying the mechanisms of solar atmospheric heating and wind acceleration can be solved only by combining quantitative models that include realistic descriptions of relevant transport processes with observational constraints on the inputs and outputs of these models. Most solar atmospheric heating, with the possible exception of flares, takes place in the chromosphere, emphasizing the importance of identifying the mechanisms of chromospheric heating, which may be important for understanding coronal heating and wind acceleration. Recent modeling leads to the conclusion that the onset of proton magnetization with increasing height in thin magnetic flux tubes triggers the onset of chromospheric network heating by resistive dissipation of Pedersen currents driven by the convection electric field of slow, longitudinal magnetoacoustic waves. C1 Catholic Univ Amer, Dept Phys, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Catholic Univ Amer, Dept Phys, Greenbelt, MD 20771 USA. EM goodman@spof02.gsfc.nasa.gov NR 53 TC 17 Z9 17 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD JAN PY 2001 VL 95 IS 1-2 BP 79 EP 93 DI 10.1023/A:1005234012443 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 391PU UT WOS:000166365000009 ER PT J AU Moore, TE Chandler, MO Fok, MC Giles, BL Delcourt, DC Horwitz, JL Pollock, CJ AF Moore, TE Chandler, MO Fok, MC Giles, BL Delcourt, DC Horwitz, JL Pollock, CJ TI Ring currents and internal plasma sources SO SPACE SCIENCE REVIEWS LA English DT Review ID BURSTY BULK FLOWS; GEOMAGNETIC STORM; EARTHS MAGNETOTAIL; HEAVY-IONS; INNER; SHEET; MAGNETOSPHERE; SUBSTORMS; DYNAMICS AB The discovery of terrestrial O+ and other heavy ions in magnetospheric hot plasmas, combined with the association of energetic ionospheric outflows with geomagnetic activity, led to the conclusion that increasing geomagnetic activity is responsible for filling the magnetosphere with ionospheric plasma. Recently it has been discovered that a major source of ionospheric heavy ion plasma outflow is responsive to the earliest impact of coronal mass ejecta upon the dayside ionosphere. Thus a large increase in ionospheric outflows begins promptly during the initial phase of geomagnetic storms, and is already present during the main phase development of such storms. We hypothesize that enhancement of the internal source of plasma actually supports the transition from substorm enhancements of aurora to storm-time ring current development in the inner magnetosphere. Other planets known to have ring current-like plasmas also have substantial internal sources of plasma, notably Jupiter and Saturn. One planet having a small magnetosphere, but very little internal source of plasma, is Mercury. Observations suggest that Mercury has substorms, but are ambiguous with regard to the possibility of magnetic storms of the planet. The Messenger mission to Mercury should provide an interesting test of our hypothesis. Mercury should support at most a modest ring current if its internal plasma source is as small as is currently believed. If substantiated, this hypothesis would support a general conclusion that the magnetospheric inflationary response is a characteristic of magnetospheres with substantial internal plasma sources. We quantitatively define this hypothesis and pose it as a problem in comparative magnetospheres. C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. NASA, George C Marshall Space Flight Ctr, Dept Space Sci, Huntsville, AL 35812 USA. CNES, CETP, St Maur, France. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. SW Res Inst, San Antonio, TX USA. RP Moore, TE (reprint author), NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RI Moore, Thomas/D-4675-2012; Fok, Mei-Ching/D-1626-2012 OI Moore, Thomas/0000-0002-3150-1137; NR 33 TC 18 Z9 18 U1 0 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD JAN PY 2001 VL 95 IS 1-2 BP 555 EP 568 DI 10.1023/A:1005264907107 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 391PU UT WOS:000166365000039 ER PT S AU Landis, GA AF Landis, GA BE ElGenk, MS TI Exploring Venus by solar airplane SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB A solar-powered airplane is proposed to explore the atmospheric environment of Venus. Venus has several advantages for a solar airplane. At the top of the cloud level, the solar intensity is comparable to or greater than terrestrial Solar intensities. The Earthlike atmospheric pressure means that the power required for flight is lower for Venus than that of Mars; and the slow rotation of Venus allows an airplane to be designed for continuous sunlight, with no energy storage needed for night-time flight. These factors mean that Venus is perhaps the easiest planet in the solar system for flight of a long-duration solar airplane. C1 NASA, John Glenn Res Ctr, Cleveland, OH 44135 USA. RP Landis, GA (reprint author), NASA, John Glenn Res Ctr, Mailstop 302-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 3 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 16 EP 18 PG 3 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300003 ER PT S AU Landis, GA AF Landis, GA BE ElGenk, MS TI Searching for life: the case for halobacteria on Mars SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB A major objective for NASA exploration of Mars is to determine whether life has existed on Mars in the past, and whether such life on Mars may persist to the present day. On Earth, life exists in all niches in which water exists in liquid form for at least a portion of the year. On Mars, any liquid water would have to be a highly concentrated brine solution. It is likely therefore, that any present-day Martian microorganisms would be similar to terrestrial halophiles. C1 NASA, John Glenn Res Ctr, Cleveland, OH 44135 USA. RP Landis, GA (reprint author), NASA, John Glenn Res Ctr, Mailstop 302-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 11 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 25 EP 28 PG 4 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300005 ER PT S AU Huntsberger, T Pirjanian, P Schenker, PS AF Huntsberger, T Pirjanian, P Schenker, PS BE ElGenk, MS TI Robotic outposts as precursors to a manned Mars habitat SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB A cost effective approach for the deployment of manned habitats on planetary surfaces is the use of robotic precursor missions far such tasks as the deployment and servicing of power systems and ISRU generators, construction of beaconed roadways, and the site preparation and deployment of manned habitat modules. Limitations in the lifetime, dexterous manipulation capabilities, control system architectures, mobility, and the overall degree of autonomy of the current generation of planetary revers such as Sojourner will have to be addressed before such a long term effort can be undertaken. Ongoing work in the Surface Systems Thrust Area under NASA's Cross Enterprise Technology Development Program (CETDP) in the area of robotic outposts is enabling many of the technology developments necessary for such an ambitious undertaking. This effort includes a strong cross section of University and NASA Center partners. The program includes the development of control architectures, ISRU systems, and new mobility designs for a sustained long term presence on planetary surfaces. This paper reviews some recent results from the JPL tasks under the Program and provides a roadmap for integration into robotic precursor missions in the 2010-2015 timeframe. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Huntsberger, T (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 46 EP 51 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300008 ER PT S AU Rochlis, JL Clarke, JP AF Rochlis, JL Clarke, JP BE ElGenk, MS TI Integrated design of a telerobotic workstation SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The experiments described in this paper are part of a larger joint MIT/NASA research effort that focuses on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multifunctional telerobots. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The exploratory research experiments presented here took an integrated approach and assessed how subjects operating a full-immersion telerobot perform during the transitions between sub-tasks of two common EVA tasks. Preliminary results show that up to 30% of total task time is spent gaining and maintaining Situation Awareness (SA) of their task space and environment during transitions. Although task performance improves over the two trial days, the percentage of lime spent on SA remains the same. This method identifies areas where workstation displays and feedback mechanisms are most needed to increase operator performance and decrease operator workload - areas that previous research methods have not been able to address. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Rochlis, JL (reprint author), NASA, Lyndon B Johnson Space Ctr, 2101 NASA Rd 1,Mail Code ER4, Houston, TX 77058 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 58 EP 63 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300010 ER PT S AU Sims, WH AF Sims, WH BE ElGenk, MS TI 2250-MHz High Efficiency Microwave Power Amplifier (HEMPA) SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB This paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10-kHz to 30-MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifer was built that demonstrated conversion efficiencies four to five times higher than current state of the art. C1 NASA, George C Marshall Space Flight Ctr, Avion Dept Engn Directorate, Radio Frequency Grp, Huntsville, AL 35812 USA. RP Sims, WH (reprint author), NASA, George C Marshall Space Flight Ctr, Avion Dept Engn Directorate, Radio Frequency Grp, Huntsville, AL 35812 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 70 EP 75 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300012 ER PT S AU Abbott, L Jochim, D Shuler, R AF Abbott, L Jochim, D Shuler, R BE ElGenk, MS TI Avionics for a small satellite SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB This paper discusses a small, seven and a half (7.5) inch diameter, satellite that NASA-JSC is developing as a technology demonstrator for an astronaut assistant. The free flyer, the Mini-AERCam. is designed to off load the flight crew's workload by performing inspections of the exteriors of the Space Shuttle or International Space Station. The Mini-AERCam is intended to be operated by the flight crew, thereby reducing the number of Extra Vehicle Activities (EVA) and reducing crew workload as a result. The paper focuses on the design constraints for a small satellite and the technology approach used to achieve the set of high performance requirements specified for the Mini-AERCam. Particular attention is paid to the flight computer as it is the system integration point of the Mini-AERCam. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Abbott, L (reprint author), NASA, Lyndon B Johnson Space Ctr, 2101 NASA Rd 1, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 83 EP 88 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300014 ER PT S AU Fullerton, RK AF Fullerton, RK BE ElGenk, MS TI Advanced EVA concepts and requirements SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB A wide variety of solutions can be theorized for the architectures, technologies and operations concepts of advanced EVA systems for future space and planetary applications. This paper reports on the status of ongoing work to capture and refine an initial set of candidate requirements. A summary of related research and development toward such an advanced system is also presented. The end goal is a cost effective, safe and resource efficient integrated system which enables work in a diversity of environments at multiple destinations. A balance of cooperative efforts between humans and automated/robotic devices is envisioned to maximize productivity and safety in remote locations. The knowledge to be captured will take advantage of past lessons learned and hoped for revolutionary solutions. This information is intended to provide credible and useful guidance for those involved in the eventual implementation, validation and utilization of an advanced EVA system. C1 NASA, Lyndon B Johnson Space Ctr, EVA Project Off, Houston, TX 77058 USA. RP Fullerton, RK (reprint author), NASA, Lyndon B Johnson Space Ctr, EVA Project Off, Mail Code XA,2101 NASA Rd 1, Houston, TX 77058 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 97 EP 102 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300016 ER PT S AU Schuiling, RL AF Schuiling, RL BE ElGenk, MS TI Lunar spaceport launch and landing operational parameters for human-based activity SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Future planning for operations on the lunar surface involving humans usually falls into two main areas of study. The first area being habitation and the second being commercial or science studies. Although much attention has been given to these two areas, very little has been given to the operations of the surface transportation node upon which they will be dependent - the "lunar spaceport" itself. Specifically, the operational factors that must be considered for flight vehicle landing, offloading, vehicle health monitoring, vehicle repair and refurbishment, reloading, and launch from the lunar surface. The complex set of parameters affecting such operations will form not only a major aspect of lunar surface operations, but a defining and limiting set of parameters for the human lunar colony or habitation element as well. The evaluation and study of such parameters as affect the launch and landing site operational environment must be conducted if lunar operations are addressed from a total systems standpoint. C1 NASA, Kennedy Space Ctr, Future Miss & Int Partners Interface Div, Int Space Stn & Payload Proc Directorate, Kennedy Space Ctr, FL 32899 USA. RP Schuiling, RL (reprint author), NASA, Kennedy Space Ctr, Future Miss & Int Partners Interface Div, Int Space Stn & Payload Proc Directorate, Mail Code UB-H, Kennedy Space Ctr, FL 32899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 109 EP 114 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300018 ER PT S AU Burley, PJ Fredrickson, SE Magruder, DF Rask, JD AF Burley, PJ Fredrickson, SE Magruder, DF Rask, JD BE ElGenk, MS TI An opposition class piloted mission to Mars using telerobotics for landing site reconnaissance and exploration SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The authors propose a new architecture for a first piloted mission to Mars. A crew travels to and from Mars in the same type of vehicle as will be used for the first piloted landing mission. Two or three surface revers travel to Mars separately. The revers land at widely separated potential human landing sites within a single hemisphere. The piloted vehicle (orbiter) achieves an orbit around Mars with a period equal to one Martian day (sol), so that continuous line-of-sight communications exists between the orbiter and the revers. The crew operates the revers from orbit using telerobotics and telepresence technology. The revers, which have traverse ranges measured in kilometers per day, perform extensive landing site reconnaissance, weather observations, and geological sample collection and analysis, including water detection experiments. The mission lasts approximately 40 days in Mars orbit. Major objectives include rigorous flight test of the piloted vehicle, precision landing site characterization and selection at a level of detail unattainable from orbit, and pre-deployment of the teleoperated revers for later use as robotic assistants during human surface missions. All of these objectives can reduce the risk to the first crew to land on Mars. Such a mission could be launched at least one synodic period ahead of the earliest planned piloted landing. C1 NASA, Lyndon B Johnson Space Ctr, Miss Operat Directorate, Orbit Dynam Branch,Flight Design & Dynam Div, Houston, TX 77058 USA. RP Burley, PJ (reprint author), NASA, Lyndon B Johnson Space Ctr, Miss Operat Directorate, Orbit Dynam Branch,Flight Design & Dynam Div, Houston, TX 77058 USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 115 EP 120 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300019 ER PT S AU Lueck, DE Parrish, CF Buttner, WJ Surma, JM AF Lueck, DE Parrish, CF Buttner, WJ Surma, JM BE ElGenk, MS TI A survey of alternative oxygen production technologies SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Utilization of the Martian atmosphere for the production of fuel and oxygen has been extensively studied. The baseline fuel production process is a Sabatier reactor, which produces methane and water from carbon dioxide and hydrogen. The oxygen produced from the electrolysis of the water is only half of that needed for methane-based rocket propellant, and additional oxygen is needed for breathing air, fuel cells and other energy sources. Zirconia electrolysis cells for the direct reduction of CO2 are being developed as an alternative means of producing oxygen, but present many challenges for a large-scale oxygen production system. The very high operating temperatures and fragile nature of the cells coupled with fairly high operating voltages leave room for improvement. This paper will survey alternative oxygen production technologies, present data on operating characteristics, materials of construction, and some preliminary laboratory results on attempts to implement each. C1 NASA, KSC, Spaceport Engn & Technol Directorate, Kennedy Space Ctr, FL 32899 USA. RP Lueck, DE (reprint author), NASA, KSC, Spaceport Engn & Technol Directorate, YA-D2, Kennedy Space Ctr, FL 32899 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 129 EP 132 PG 4 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300021 ER PT S AU Parrish, CF Lueck, DE Jennings, PA AF Parrish, CF Lueck, DE Jennings, PA BE ElGenk, MS TI Buffer gas acquisition and storage SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The acquisition and storage of buffer gases (primarily argon and nitrogen) from the Mars atmosphere provides a valuable resource for blanketing and pressurizing fuel tanks and as a buffer gas for breathing air for manned missions. During the acquisition of carbon dioxide (CO2), whether by sorption bed or cryo- freezer, the accompanying buffer gases build up in the carbon dioxide acquisition system, reduce the flow of CO2 to the bed, and lower system efficiency. it is this build up of buffer gases that provide a convenient source, which must be removed, for efficient capture of CO2. Removal of this buffer gas barrier greatly improves the charging rate of the CO2 acquisition bed and, thereby, maintains the fuel production rates required for a successful mission. Consequently, the acquisition, purification, and storage of these buffer gases are important goals of ISRU plans. Purity of the buffer gases is a concern e.g., if the CO2 freezer operates at 140K, the composition of the inert gas would be approximately 21 percent CO2, 50 percent nitrogen, and 29 percent argon. Although there are several approaches that could be used, this effort focused on a hollow-fiber membrane (HFM) separation method. This study measured the permeation rates of CO2, nitrogen (N-2), and argon (Ar) through a multiple-membrane system and the individual membranes from room temperature to 193K and 10kPa to 300kPa. Concentrations were measured with a gas chromatograph. The end result was data necessary to design a system that could separate CO2, N-2, and Ar. C1 NASA, Spaceport Engn & Technol Directorate, Kennedy Space Ctr, FL 32899 USA. RP Parrish, CF (reprint author), NASA, Spaceport Engn & Technol Directorate, YA-D2, Kennedy Space Ctr, FL 32899 USA. NR 6 TC 0 Z9 0 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 133 EP 138 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300022 ER PT S AU Patterson, LP AF Patterson, LP BE ElGenk, MS TI On-Orbit Maintenance operations strategy for the International Space Station - Concept and implementation SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The International Space Station (ISS) has an operational mission and profile that makes it a Logistics and Maintenance (L&M) support challenge different from previous programs. It is permanently manned, assembled on orbit, and multi-national. With this technical and operational challenge, a unique approach is needed to support the hardware and crew. The key is the integration of on-orbit and ground analysis, supply; maintenance, and crew training into a coherent functional process that supports ISS goals and objectives. To integrate all the necessary aspects of hardware and personnel to support on-orbit maintenance, a myriad of products and processes must be created and coordinated, such that the right resources are in the right place at the right time to ensure continued ISS functionality. This paper will familiarize the audience with ISS On-Orbit Maintenance (OOM) concepts and capabilities for different maintenance tasks and discuss some of the logic behind their selection. It will also identify the operational maintenance support responsibility split between the U.S. and the various International Partners (IPs). C1 NASA, Lyndon B Johnson Space Ctr, Mechanisms & Maintenance Grp, Syst Div,Mission Operat Directorate, Houston, TX 77058 USA. RP Patterson, LP (reprint author), NASA, Lyndon B Johnson Space Ctr, Mechanisms & Maintenance Grp, Syst Div,Mission Operat Directorate, DF53, Houston, TX 77058 USA. NR 3 TC 1 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 139 EP 146 PG 8 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300023 ER PT S AU Butina, AJ AF Butina, AJ BE ElGenk, MS TI Managing NASA's International Space Station Logistics and Maintenance program SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The International Space Station will be a permanently manned orbiting vehicle that has no landing gear, no international borders, and no organizational lines - it is one Station that must be supported by one crew, 24 hours a day, 7 days a week, 365 days a year. It flies partially assembled for a number of years before it is finally complete in April of 2006. Space logistics is a new concept that will have wide reaching consequences for both space travel and life on Earth. What is it like to do something that no one has done before? What challenges do you face? What kind of organization do you put together to perform this type of task? How do you optimize your resources to procure what you need? How do you change a paradigm within a space agency? How do you coordinate and manage a one of a kind system with approximately 5,700 Orbital Replaceable Units (ORUs)? How do you plan for preventive and corrective maintenance, when you need to procure spare parts which number into the hundreds of thousands, from 127 major US vendors and 70 major international vendors? How do you transport large sections of ISS hardware around the country? These are some of the topics discussed in this paper. From conception to operation, the ISS requires a unique approach in all aspects of development and operation. Today the dream is coming true; hardware is flying and hardware is failing. The system has been put into place to support the Station and only time will tell if we did it right. This paper discusses some of the experiences of the author after working 12 years on the International Space Station's integrated logistics & maintenance program. From his early days as a contractor supportability engineer and manager, to the NASA manager responsible for the entire ISS Logistics and Maintenance program. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77059 USA. RP Butina, AJ (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77059 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 161 EP 169 PG 9 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300026 ER PT S AU Werneth, RL AF Werneth, RL BE ElGenk, MS TI Lessons learned from Hubble Space Telescope extravehicular activity supportability SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB NASA's Hubble Space Telescope was designed for supportability by Space Shuttle astronauts performing extravehicular activities (EVAs), or spacewalks: to service, maintain, repair, and upgrade the telescope. Through three successful servicing missions to date, EVA processes have been developed by applying a series of important lessons learned. These lessons learned are also applicable to many other future human spaceflight and robotic missions, such as International Space Station, satellite retrieval and servicing, and long-duration spaceflight. HST has become NASA's pathfinder for observatories, EVA development, and EVA mission execution. C1 NASA, Goddard Space Flight Ctr, HST Project Off, Greenbelt, MD 20771 USA. RP Werneth, RL (reprint author), NASA, Goddard Space Flight Ctr, HST Project Off, Greenbelt, MD 20771 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 176 EP 188 PG 13 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300028 ER PT S AU Jacobson, C Meade, P AF Jacobson, C Meade, P BE ElGenk, MS TI Streamlined payload processing in the 21(st) Century SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Launching payloads into space continues to be a weekly occurrence around the world. Although it is becoming commonplace, it has not become a low-cost or low-risk, quick and simple process. Out of these conditions: concepts have been developed and efforts are underway to create a generic set of processes and tools that will advance payload processing into the 21(st) Century by making it more efficient and less complicated. These new approaches are developing more cost effective, shorter cycle time processes, and require fewer resources than in the past. The KSC Center of Excellence for Payload Processing, built on the last 40 years of experience in processing all types of payloads (Shuttle, Expendable, Space Station, etc.), has been addressing these areas. Development is complete and operations are underway on the high fidelity checkout system used to perform final verification of flight interfaces between the International Space Station (ISS) and its science experiments. This system is typical of what has been used in the past for verifying interfaces which include: high, medium, and low rate data communications; video, command and data handling; power; and fluids/gases. The system also contains an ISS Program equivalent ground station, which will receive and process payload telemetry and distribute that telemetry to the appropriate customers. The recently developed concepts and projects underway address the lifecycle of payload processing, integrating agency and customer needs and requirements, and support geographically distributed processing. These concepts have driven out areas of synergy and leverage which enable large improvements to be proposed for payloads headed for Space Station or flying on Shuttle. C1 NASA, Future Missions & Int Partner Div, Kennedy Space Ctr, FL 32899 USA. RP Jacobson, C (reprint author), NASA, Future Missions & Int Partner Div, Mail Code UB-H, Kennedy Space Ctr, FL 32899 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 189 EP 195 PG 7 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300029 ER PT S AU Gavert, RB AF Gavert, RB BE ElGenk, MS TI Three near term commercial markets in space and their potential role in space exploration SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Independent market studies related to Low Earth Orbit (LEO) commercialization have identified three near term markets that have return-on-investment potential. These markets are: (1) Entertainment (2) Education (3) Advertising/sponsorship. Commercial activity is presently underway focusing on these areas. A private company is working with the Russians on a commercial module attached to the ISS that will involve entertainment and probably the other two activities as well. A separate corporation has been established to commercialize the Russian Mir Space Station with entertainment and promotional advertising as important revenue sources. A new startup company has signed an agreement with NASA for commercial media activity on the International Space Station (ISS). Profit making education programs are being developed by a private firm to allow students to play the role of an astronaut and work closely with space scientists and astronauts. It is expected that the success of these efforts on the ISS program will extend to exploration missions beyond LEG. The objective of this paper is to extrapolate some of the LEO commercialization experiences to see what might be expected in space exploration missions to Mars, the Moon and beyond. C1 NASA, Space Utilizat & Prod Dev Div, Washington, DC 20546 USA. RP Gavert, RB (reprint author), NASA, Space Utilizat & Prod Dev Div, 300 E St SW, Washington, DC 20546 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 196 EP 201 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300030 ER PT S AU Tam, DC AF Tam, DC BE ElGenk, MS TI The business of space exploration SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Despite healthy economic conditions worldwide, aerospace companies have been struggling since the end of the Cold War. The industry faces a very uncertain future as people and money are leaving in droves. But that has not diminished interest in significantly opening up the space frontier for commercial uses. Is there a major disconnect between expectation and reality? What can the Government and private sectors do to positively shape the future? This paper examines the market forces in play and uses the development of the commercial air transportation business to assess the prospect for commercial space transportation and exploration. It also addresses the elements and criteria for business opportunity, and suggests ways in which the public and private sector can work together to build the future of space. C1 NASA, Washington, DC 20546 USA. RP Tam, DC (reprint author), NASA, 300 E St SW,Mail Code AJ, Washington, DC 20546 USA. NR 4 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 202 EP 205 PG 4 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300031 ER PT S AU Ku, JT Ottenstein, L Kobel, M Rogers, P Kaya, T AF Ku, JT Ottenstein, L Kobel, M Rogers, P Kaya, T BE ElGenk, MS TI Temperature oscillations in loop heat pipe operation SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Loop heat pipes (LHPs) are versatile two-phase heat transfer devices that have gained increasing acceptance for space and terrestrial applications. The operating temperature of an LHP is a function of its operating conditions. The LHP usually reaches a steady operating temperature for a given heat load and sink temperature. The operating temperature will change when the heat load and/or the sink temperature changes, but eventually reaches another steady state in most cases. Under certain conditions, however, the loop operating temperature never really reaches a true steady state, but instead becomes oscillatory. This paper discusses the temperature oscillation phenomenon using test data from a miniature LHP. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ku, JT (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 5 TC 23 Z9 28 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 255 EP 262 PG 8 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300037 ER PT S AU Birur, GC O'Donnell, TP AF Birur, GC O'Donnell, TP BE ElGenk, MS TI Advanced thermal control technologies for space science missions at Jet Propulsion Laboratory SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB A wide range of deep space science missions is planned by the National Aeronautics and Space Administration. These missions include planetary orbiters, planetary landers/rovers, planet/comet flybys, and planet/comet sample return missions. Many of these missions are being planned under strict cost caps and advanced technologies are needed in order to enable these challenging missions. Because of the wide range of thermal environments which the spacecraft experience during the mission, developing an appropriate thermal control system for the spacecraft is both complicated and challenging. Advanced thermal control technologies, the key to enabling many of these missions, are being developed at the Jet Propulsion Laboratory (JPL). The wide range of applications include: temperature control, minimizing heat losses, precision temperature control of large structures, universal thermal architecture for future missions, microspacecraft thermal technologies, and micro-electromechanical systems based thermal technologies for micro/nano spacecraft. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Birur, GC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 9 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 263 EP 270 PG 8 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300038 ER PT S AU Davis, D AF Davis, D BE ElGenk, MS TI Thermal analysis of the MC-1 chamber/nozzle SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB This paper will describe the thermal analysis techniques used to predict temperatures in the film-cooled ablative rocket nozzle used on the MC-I 60K rocket engine. A model was developed that predicts char and pyrolysis depths, liner thermal gradients. and temperatures of the bondline between the overwrap and liner. Correlation of the model was accomplished by thermal analog tests performed at Southern Research, and specially instrumented hot fire tests at the Marshall Space Flight Center. Infrared thermography was instrumental in defining nozzle hot wall surface temperatures. In-depth and outboard thermocouple data was used to correlate the kinetic decomposition routine used to predict char and pyrolysis depths. These depths were anchored with measured char and pyrolysis depths from cross-sectioned hot-fire nozzles. For the X-34 night analysis, the model includes the ablative Thermal Protection System (TPS) material that protects the overwrap from the recirculating plume. Results from model correlation, hot-fire testing, and night predictions will be discussed. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Davis, D (reprint author), NASA, George C Marshall Space Flight Ctr, ED25, Huntsville, AL 35812 USA. NR 1 TC 1 Z9 1 U1 2 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 292 EP 297 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300042 ER PT S AU Stuckey, CI Reinarts, TR Davis, D AF Stuckey, CI Reinarts, TR Davis, D BE ElGenk, MS TI Thermal characterization of an epoxy-based composite sandwich nose cap design for the space shuttle solid rocket booster SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB A recent effort was undertaken to develop an epoxy-based composite nose cap for the space shuttle solid rocket boosters (SRBs). Although this project was suspended in November 1999, a significant amount of thermal characterization testing was conducted on the design. The results from this effort are presented. The symmetric composite sandwich consisted of a core of epoxy-based syntactic foam (3M SC350G) sandwiched between composite laminates (Hexcel's AGP370 -8H/3501-6). The composite laminates provide structural strength and the syntactic foam serves as a thermal barrier. Three lots of each composite material were tested as part of the material characterization in an attempt to quantify lot to lot variability. A total of ninety-one test panels were tested in the Improved Hot Gas Facility (IHGF). Some of these were pre-conditioned prior to testing in the IHGF using humidity chambers, ovens, lightning strikes, or actual beach exposure. The majority of panels were tested at simulated flight design thermal environments, but some panels were intentionally over-tested to ensure that potential failure modes were enveloped while other panels were tested to failure. During much of the testing, several layers of the heated laminate surpassed the glass transition temperature of the epoxy (Tg approximate to 464 K). Little information exists on such materials beyond Ts, and so the data presented here increase that database significantly. The results of the present study indicate that, as far as thermal requirements are concerned, a nose cap made of this sandwich and topcoated with Hypalon paint should be an adequate replacement for the aluminum nose cap that is currently being used on the SRBs. C1 NASA, KSC, Kennedy Space Ctr, FL 32815 USA. RP Stuckey, CI (reprint author), NASA, KSC, VB A3, Kennedy Space Ctr, FL 32815 USA. NR 5 TC 2 Z9 2 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 298 EP 303 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300043 ER PT S AU Reinarts, TR Davis, D Stuckey, CI AF Reinarts, TR Davis, D Stuckey, CI BE ElGenk, MS TI Calibration of an analytical thermal model for an epoxy-based composite sandwich design SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB An epoxy-based sandwich configuration was designed to meet the structural and thermal requirements of a nose cap for the space shuttle solid rocket boosters (SRB's). This project was suspended in late 1999, but the information gathered during this work is unique in the sense that portions of graphite-epoxy layers were modeled at temperatures exceeding their glass transition temperatures. This work presents the results of the thermal model calibration efforts. A symmetric sandwich configuration was chosen that includes an inner and outer structural skin with a graphite-epoxy composite, Hexcel's AGP370 -8H/3501-6 (AS4/3501-6), and a center epoxy-based syntactic core, 3M SC350G, that provides thermal protection. Each graphite-epoxy section consists of seven layers, each layer with a 0 degrees, 90 degrees, or +/- 45 degrees graphite fiber orientation. Three flat panels (0.305 x 0.483 m top view dimensions) using this sandwich construction were fabricated and exposed to an aerothermal environment in the Marshall Space Flight Center (MSFC) Improved Hot Gas Facility (IHGF). Each of these panels had ten interstitial thermocouples in the panel. The exact locations of the thermocouples and thickness of the different layers were determined by X-ray evaluation. A I-D model was generated that used the outer surface IR measured temperature as a boundary condition, and the predicted temperatures were compared with the measured temperatures, calibrating the code. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Reinarts, TR (reprint author), NASA, George C Marshall Space Flight Ctr, MC ED 25, Huntsville, AL 35812 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 304 EP 309 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300044 ER PT S AU Didion, JR AF Didion, JR BE ElGenk, MS TI A prototype electrohydrodynamic driven thermal control system (EHD-TCS) SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Goddard Space Flight Center has designed and fabricated a novel, prototype thermal control system operated solely by electrohydrodynamic (EHD) forces. The EHD-TCS consists of an EHD pumping section, transport tubing, a thermal-hydraulic test section, and a condenser section. The prototype loop has been fabricated to characterize the operations of the EHD-TCS and to investigate specific applications of EHD techniques to flow management and heat transfer enhancement. This paper discusses operational issues regarding an EHD conduction pump in the EHD-TCS. In the preliminary testing presented herein, the EHD-TCS loop operated as a single-phase thermal control system. The EHD conduction pump performance is characterized in the following terms: (i) mass flow rate versus applied voltage and applied current and (ii) pressure head developed by the pump as a function of applied voltage and current. Other relevant performance issues such as determination of steady state and operational power requirements are presented. The conduction pump operated reliably with no operational failures for up to 120 hours. Operational differences between static loop and EHD-TCS performance are noted. Hypotheses regarding possible explanations are discussed. The remaining engineering and technical challenges in this development program are outlined. C1 NASA, Goddard Space Flight Ctr, Thermal Engn Branch, Greenbelt, MD 20771 USA. RP Didion, JR (reprint author), NASA, Goddard Space Flight Ctr, Thermal Engn Branch, Greenbelt, MD 20771 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 310 EP 315 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300045 ER PT S AU Rogers, JR Hyers, RW Rathz, T Savage, L Robinson, MB AF Rogers, JR Hyers, RW Rathz, T Savage, L Robinson, MB BE ElGenk, MS TI Thermophysical property measurement and materials research in the NASA/MSFC electrostatic levitator. SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP Conference Proceedings LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID VISCOSITY AB Containerless processing is an important tool for thermophysical property measurements and materials research. The freedom from a crucible allows processing of liquid materials in a metastable undercooled state, as well as allowing processing of high temperature and highly reactive melts. Electrostatic levitation (ESL) is a containerless method which provides a number of unique advantages, including the decoupling of positioning force from sample heating, the ability to operate in ultra-high vacuum or at moderate gas pressure (similar to3 atm), and the ability to process non-conducting materials. ESL also has the potential to reduce internal flow velocities below those possible with electromagnetic, acoustic, or aeroacoustic techniques. The ESL facility at NASA's Marshall Space Flight Center (MSFC) is in use for thermophysical property measurements and materials research by a number of different internal and external investigators. The methods for obtaining access to the facility, as well as a summary of current capabilities and some future directions will be discussed. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Rogers, JR (reprint author), NASA, George C Marshall Space Flight Ctr, Mail Code SD47, Huntsville, AL 35812 USA. EM jan.rogers@msfc.nasa.gov RI Hyers, Robert/G-3755-2010 NR 14 TC 4 Z9 4 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 332 EP 336 PG 5 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300048 ER PT S AU Landis, GA AF Landis, GA BE ElGenk, MS TI Interstellar flight by particle beam SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Two difficulties with the use of laser-propelled lightsails for interstellar propulsion are the extremely low energy efficiency, and the extremely large lenses required. Both the energy efficiency and the required lens size may be greatly improved by use of a particle beam, rather than a light beam. The particle beam is reflected by a magnetic field on the spacecraft, for example, by a magnetic sail or a mini-magnetosphere inflated by a plasma current. This results in a net force on the sail with no expenditure of propellant, allowing extremely high delta-V missions, such as an interstellar probe, to be accomplished. C1 NASA, John Glenn Res Ctr, Cleveland, OH 44135 USA. RP Landis, GA (reprint author), NASA, John Glenn Res Ctr, Mailstop 302-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 14 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 393 EP 396 PG 4 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300057 ER PT S AU Ballance, J Johnson, L AF Ballance, J Johnson, L BE ElGenk, MS TI Propulsive Small Expendable Deployer System (ProSEDS) SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The Propulsive Small Expendable Deployer System (ProSEDS) space experiment will demonstrate the use of an electrodynamic tether propulsion system to generate thrust in space by decreasing the orbital altitude of a Delta II expendable launch vehicle (ELV) second stage. ProSEDS, which is planned to fly in 2001, will use the flight-proven Small Expendable Deployer System (SEDS) to deploy a tether (5-km bare wire plus 10-km spectra or dyneema) from a Delta II second stage to achieve similar to0.4 N drag thrust. ProSEDS will utilize the tether-generated current to provide limited spacecraft power. The ProSEDS instrumentation includes a Langmuir probe and differential ion flux probe, which will determine the characteristics of the ambient ionospheric plasma. Two global positioning system (GPS) receivers will be used (one on the Delta and one on the endmass) to help determine tether dynamics and to limit transmitter operations to occasions when the spacecraft is over selected ground stations. The flight experiment is a precursor to the more ambitious electrodynamic tether upperstage demonstration mission, which will be capable of orbit raising, lowering, and inclination changes - all using electrodynamic thrust. An immediate application of ProSEDS technology is for the deorbit of spent satellites for orbital debris mitigation. In addition to the use of this technology to provide orbit transfer and debris mitigation, it may also be an attractive option for future missions to Jupiter and any other planetary body with a magnetosphere. C1 NASA, George C Marshall Space Flight Ctr, Dept Space Transportat, Huntsville, AL 35812 USA. RP Ballance, J (reprint author), NASA, George C Marshall Space Flight Ctr, Dept Space Transportat, Huntsville, AL 35812 USA. NR 1 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 419 EP 424 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300062 ER PT S AU Dickinson, RM AF Dickinson, RM BE ElGenk, MS TI Interstellar beamer engineering SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The fundamental differences between solar sails and interstellar beam Riders are presented. Design requirements and design considerations are developed for an interstellar beamer phased array of gigantic proportions for photon pushing beam riding spacecraft to significant fractions of the speed of light. Considerations for beam safety and beamer security are discussed. A suggested asteroid is selected for providing raw materials and a construction base. Means for financing and the economics of the beamer are presented, along with comparisons of the World's energy production and some rate of asset growth histories for putting such a large endeavor into perspective. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Dickinson, RM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 565 EP 570 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300083 ER PT S AU Lueck, DE Parrish, CF AF Lueck, DE Parrish, CF BE ElGenk, MS TI Closed end launch tube (CELT) SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB As an alternative to magnetic propulsion for launch assist, the authors propose a pneumatic launch assist system. Using off-the-shelf components, coupled with familiar steel and concrete construction, a launch assist system can be brought from the initial feasibility stage, through a flight capable 5000 kg demonstrator to a deployed full size launch assist system in 10 years. The final system would be capable of accelerating a 450,000 kg vehicle to 270 ms(-1). The CELT system uses commercially available compressors and valves to build a fail-safe system in less than half the time of a full Mag-Lev (magnetic levitation) system, and at a small fraction of the development cost. The resulting system could be ready in time to support some Gen 2 (Generation 2) vehicles, as well as the proposed Gen 3 vehicle. C1 NASA, Kennedy Space Ctr, Spaceport Engn & Technol Directorate, Kennedy Space Ctr, FL 32899 USA. RP Lueck, DE (reprint author), NASA, Kennedy Space Ctr, Spaceport Engn & Technol Directorate, YA-D2, Kennedy Space Ctr, FL 32899 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 660 EP 664 PG 5 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300095 ER PT S AU Kanki, BG Barth, T Blankmann-Alexander, D Parker, DB Coan, H AF Kanki, BG Barth, T Blankmann-Alexander, D Parker, DB Coan, H BE ElGenk, MS TI Human factors engineering of enhanced spaceport procedures SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Because operational procedures provide a first line of defense against human error, human-centered design is key for streamlining work processes, standardizing work practices, and providing invaluable reminders and cautions during high risk, complex operations. In contrast, inaccurate or poorly designed operational procedures and documentation can impede the work process, encourage unsafe work practices, and confuse or mislead operators during safety critical steps. In response to several internal KSC studies that concluded that operational procedures (work instructions) were the leading contributors to Shuttle ground processing incidents and inefficiencies, the Shuttle Work Instruction Task Team (WITT) was chartered to develop a vision for a new work instruction system. This paper describes some of the original WITT recommendations and activities: as well as collaborative human factors engineering projects supporting the WITT efforts. Past achievements as well as ongoing and planned initiatives to provide continued support for the enhancement of spaceport procedures are described. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Kanki, BG (reprint author), NASA, Ames Res Ctr, MS 262-4, Moffett Field, CA 94035 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 665 EP 670 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300096 ER PT S AU Fox, JJ AF Fox, JJ BE ElGenk, MS TI Informed maintenance for next generation space transportation systems SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Perhaps the most substantial single obstacle to progress of space exploration and utilization of space for human benefit is the safety & reliability and the inherent cost of launching to, and returning from, space. The primary influence in the high costs of current launch systems (the same is true for commercial and military aircraft and most other reusable systems) is the operations, maintenance and infrastructure portion of the program's total life cycle costs. Reusable Launch Vehicle (RLV) maintenance and design have traditionally been two separate engineering disciplines with often conflicting objectives - maximizing ease of maintenance versus optimizing performance, size and cost. Testability analysis, an element of Informed Maintenance (IM), has been an ad hoc, manual effort, in which maintenance engineers attempt to identify an efficient method of troubleshooting for the given product, with little or no control over product design. Therefore, testability deficiencies in the design cannot be rectified. It is now widely recognized that IM must be engineered into the product at the design stage itself, so that an optimal compromise is achieved between system maintainability and performance. The elements of IM include testability analysis, diagnostics/prognostics, automated maintenance scheduling, automated logistics coordination, paperless documentation and data mining. IM derives its heritage from complimentary NASA science, space and aeronautic enterprises such as the on-board autonomous Remote Agent Architecture recently flown on NASA's Deep Space 1 Probe as well as commercial industries that employ quick turnaround operations. Commercial technologies and processes supporting NASA's IM initiatives include condition based maintenance technologies from Boeing's Commercial 777 Aircraft and Lockheed-Martin's F-22 Fighter, automotive computer diagnostics and autonomous controllers that enable 100,000 mile maintenance free operations, and locomotive monitoring system software. This paper will summarize NASA's long-term strategy, development, and implementation plans for Informed Maintenance for next generation RLVs. This will be done through a convergence into a single IM vision the work being performed throughout NASA, industry and academia. Additionally, a current status of IM development throughout NASA programs such as the Space Shuttle, X-33, X-34 and X-37 will be provided and will conclude with an overview of near-term work that is being initiated in FY00 to support NASA's 2(nd) Generation Reusable Launch Vehicle Program. C1 NASA, Kennedy Space Ctr, Kennedy Space Ctr, FL 32815 USA. RP Fox, JJ (reprint author), NASA, Kennedy Space Ctr, Kennedy Space Ctr, FL 32815 USA. NR 11 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 671 EP 679 PG 9 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300097 ER PT S AU Ferrell, B Haley, S AF Ferrell, B Haley, S BE ElGenk, MS TI Autonomous system for launch vehicle range safety SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The Autonomous Flight Safety System (AFSS) is a launch vehicle subsystem whose ultimate goal is an autonomous capability to assure range safety (people and valuable resources), flight personnel safety, flight assets safety (recovery of valuable vehicles and cargo), and global coverage with a dramatic simplification of range infrastructure. The AFSS is capable of determining current vehicle position and predicting the impact point with respect to flight restriction zones. Additionally, it is able to discern whether or not the launch vehicle is an immediate threat to public safety, and initiate the appropriate range safety response. These features provide for a dramatic cost reduction in range operations and improved reliability of mission success. C1 NASA, Kennedy Space Ctr, FL 32899 USA. RP Ferrell, B (reprint author), NASA, Kennedy Space Ctr, FL 32899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 686 EP 692 PG 7 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300099 ER PT S AU Nilsen, EN AF Nilsen, EN BE ElGenk, MS TI Advanced radioisotope power sources for future deep space missions SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The use of Radioisotope Thermoelectric Generators (RTGs) has been well established for deep space mission applications. The success of the Voyager, Galileo, Cassini and numerous other missions proved the efficacy of these technologies in deep space. Future deep space missions may also require Advanced Radioisotope Power System (ARPS) technologies to accomplish their goals. In the Exploration of the Solar System (ESS) theme, several missions are in the planning stages or under study that would be enabled by ARPS technology. Two ESS missions in the planning stage may employ ARPS. Currently planned for launch in 2006, the Europa Orbiter mission (EO) will perform a detailed orbital exploration of Jupiter's moon Europa to determine the presence of liquid water under the icy surface. An ARPS based upon Stirling engine technology is currently baselined for this mission. The Pluto Kuiper Express mission (PKE), planned for launch in 2004 to study Pluto, its moon Charon, and the Kuiper belt, is baselined to use a new RTG (F-8) assembled from parts remaining from the Cassini spare RTG. However, if this unit is unavailable, the Cassini spare RTG (F-5) or ARPS technologies would be required. Future missions under study may also require ARPS technologies. Mission studies are now underway for a detailed exploration program for Europa, with multiple mission concepts for landers and future surface and subsurface explorers. For the orbital phase of these missions, ARPS technologies may provide the necessary power for the spacecraft and orbital telecommunications relay capability for landed assets. For extended surface and subsurface operations, ARPS may provide the power for lander operations and for drilling. Saturn Ring Observer (SRO) will perform a detailed study of Saturn's rings and ring dynamics. The Neptune Orbiter (NO) mission will perform a detailed multi disciplinary study of Neptune. Titan Explorer (TE) will perform in-situ exploration of Saturn's moon Titan, with both orbital operations and landed operations enabled by ARPS technologies. All of these missions would be enabled by ARPS technology. This paper presents the current status of ongoing studies of future ESS mission concepts and the design assumptions and capabilities required from ARPS technologies. Where specific capabilities have been assumed in the studies, the results are presented along with a discussion of the implementation alternatives. No decision on power sources would be made until after completion of an Environmental Impact Statement for each project. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Nilsen, EN (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 701 EP 706 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300101 ER PT S AU Zimmerman, W Bryant, S Zitzelberger, J Nesmith, B AF Zimmerman, W Bryant, S Zitzelberger, J Nesmith, B BE ElGenk, MS TI A radioisotope powered Cryobot for penetrating the Europan ice shell SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The Cryobot team at JPL has been working on the design of a Cryo-Hydro Integrated Robotic Penetrator System (CHIRPS), which can be used to penetrate the Mars North Polar Cap or the thick sheet ice surrounding Jupiter's moon, Europa The science for either one of these missions is compelling. For both Mars and Europa the major scientific interest is to reach regions where there is a reservoir of water that may yield signs of past or extant life. Additionally, a Mars polar cap penetration would help us understand both climatic and depositional histories for perhaps as far back as 20 million years. Similarly, penetration of the Europa ice sheet would allow scientists to unravel the mysteries surrounding the thick ice crust, its chemical composition, and subsurface ocean properties. Extreme mass and power constraints make deep drilling/coring impractical. The best way to explore either one of these environments is a cryobot mole penetrator vehicle, which carries a suite of instruments suitable for sampling and analyzing the ice or ocean environments. This paper concentrates on a Europa deep ice (i.e., kilometers thick) application of the CHIRPS, and introduces the reader to the vehicle design with focus on the use of radioisotope thermoelectric generator (RTG) technology as the primary heat (1 kW total) and power source for the robotic vehicle. Radioisotope heater unit (RHU) milli-watt power systems (120 mW total) are also employed to power the mini-radiowave ice transceivers, which are used to relay data through the ice up to the surface lander. The results of modeling and design work for both of these areas are discussed in this paper. Although radioisotope power is baselined for the Europa flight version of the cyrobot, no decision on the final design of the cryobot will be made until the environmental review process is complete. Any use of the cryobot for Mars or Europa will conform to all environmental and planetary protection requirements. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Zimmerman, W (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 3 Z9 3 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 707 EP 715 PG 9 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300102 ER PT S AU Gavit, SA Liewer, PC Wallace, RA Ayon, JA Frisbee, RH AF Gavit, SA Liewer, PC Wallace, RA Ayon, JA Frisbee, RH BE ElGenk, MS TI Interstellar travel - Challenging propulsion and power technologies for the next 50 years SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB In February, 1999, the National Aeronautics and Space Administration's (NASA's) Jet Propulsion Laboratory (JPL) established an Interstellar and Solar Sail Technology Program, whose goal is to launch exploratory spacecraft to the near interstellar medium in the next 10 years, and to the nearest star within the next 40 years. Later that year, NASA's Sun-Earth-Connection (SEC) subcommittee established a new quest and a campaign entitled "Explore the Boundaries of the Heliospere and Near Interstellar Environment" to its roadmap theme, with the Interstellar Probe proposed to launch as a flagship mission at earliest in 2010. At last, travel to our nearby interstellar medium may be possible in the near future due to recent technological advances, especially in the areas of ultra-lightweight structures, materials, and electronics. Interstellar travel provides a challenging vision for space technologies, as velocities of up to 20 AU/Year are required for near interstellar medium travel, and up to half the speed of light are desired to reach the nearest stars. This paper will propose one vision for an interstellar program. It will include a discussion of mission concepts as well as technological requirements for accomplishing those missions. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gavit, SA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 6 TC 0 Z9 0 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 716 EP 726 PG 11 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300103 ER PT S AU Juhasz, AJ AF Juhasz, AJ BE ElGenk, MS TI An analysis and procedure for determining space environmental sink temperatures with selected computational results SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The heat transfer problem posed by the determination of spacecraft temperatures is analyzed and the theoretically derived relationships are included in a computational code. Subject code (TSCALC) is based theoretical analysis of thermal radiative equilibrium in space, particularly in the Solar System. Starting with the solar luminosity, the code takes in to account a number of key variables, namely: the spacecraft-to-Sun distance expressed in Astronomical Units (AU); the angle in degrees at which solar radiation is incident on a spacecraft surface, the temperature of which is to be determined; the absorptivity to emissivity ratio of the surface, (alpha/epsilon)(1) with respect to solar radiation; and the view factor of the surface to space. For spacecraft in planetary circular orbits at various altitudes above the planet surface, the code will also compute the spacecraft surface temperature rise due to albedo (reflected solar radiation from the planetary surface), direct (infrared) planetary surface radiation, characterized by a second absorptivity to emissivity ratio, (alpha/epsilon)(2), and any on-board internal heat generation or heat removal. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Juhasz, AJ (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 805 EP 814 PG 10 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300116 ER PT S AU Houts, M Van Dyke, M Godfroy, T Pedersen, K Martin, J Dickens, R Salvail, P Hrbud, I AF Houts, M Van Dyke, M Godfroy, T Pedersen, K Martin, J Dickens, R Salvail, P Hrbud, I BE ElGenk, MS TI Options for development of space fission propulsion systems SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Fission technology can enable rapid, affordable access to any point in the solar system. Potential fission-based transportation options include high specific power continuous impulse propulsion systems; and bimodal nuclear thermal rockets. Despite their tremendous potential for enhancing or enabling deep space and planetary missions, to date space fission systems have only been used in Earth orbit. The first step towards utilizing advanced fission propulsion systems is development of a safe, near-term, affordable fission system that can enhance or enable near-term missions of interest. An evolutionary approach for developing space fission propulsion systems is proposed. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Houts, M (reprint author), NASA, George C Marshall Space Flight Ctr, TD40, Huntsville, AL 35812 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 822 EP 827 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300118 ER PT S AU Van Dyke, M Houts, M Pedersen, K Godfroy, T Dickens, R Poston, D Reid, B Salvail, P Ring, P AF Van Dyke, M Houts, M Pedersen, K Godfroy, T Dickens, R Poston, D Reid, B Salvail, P Ring, P BE ElGenk, MS TI Phase 1 space fission propulsion system testing and development progress SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Successful development of space fission systems will require an extensive program of affordable and realistic testing. In addition to tests related to design/development of the fission system, realistic testing of the actual flight unit must also be performed. Testing can be divided into two categories, non-nuclear tests and nuclear tests. Full power nuclear tests of space fission systems are expensive, time consuming, and of limited use, even in the best of programmatic environments. If the system is designed to operate within established radiation damage and fuel burn up limits while simultaneously being designed to allow close simulation of heat from fission using resistance heaters, high confidence in fission system performance and lifetime can be attained through a series of non-nuclear tests. Non-nuclear tests are affordable and timely, and the cause of component and system failures can be quickly and accurately identified. MSFC is leading a Safe Affordable Fission Engine (SAFE) test series whose ultimate goal is the demonstration of a 300 kW flight configuration system using non-nuclear testing. This test series is carried out in collaboration with other NASA centers, other government agencies, industry, and universities. If SAFE-related nuclear tests are desired, they will have a high probability of success and can be performed at existing nuclear facilities. The paper describes the SAFE non-nuclear test series, which includes test article descriptions, test results and conclusions, and future test plans. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Van Dyke, M (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 2 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 837 EP 842 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300120 ER PT S AU Pedersen, K Van Dyke, M Houts, M Godfroy, T Martin, J Dickens, R Williams, E Harper, R Salvil, P Reid, B AF Pedersen, K Van Dyke, M Houts, M Godfroy, T Martin, J Dickens, R Williams, E Harper, R Salvil, P Reid, B BE ElGenk, MS TI Results of 30 kWt Safe Affordable Fission Engine (SAFE-30) primary heat transport testing SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP Conference Proceedings LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The use of resistance heaters to simulate heat from fission allows extensive development of fission systems to be performed in non-nuclear test facilities, saving time and money. Resistance heated tests on the Safe Affordable Fission Engine - 30 kilowatt (SAFE30) test article are being performed at the Marshall Space Flight Center. This paper discusses the results of these experiments to date, and describes the additional testing that will be performed. Recommendations related to the design of testable space fission power and propulsion systems are made. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Pedersen, K (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. EM Kevin.Pedersen@msfc.nasa.gov NR 6 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 843 EP 848 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300121 ER PT S AU Roman, J AF Roman, J BE ElGenk, MS TI Safe Affordable Fission Engine (SAFE 30) module conductivity test thermal model correlation. SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The SAFE 30 is a simple, robust space fission power system that is comprised of several independent modules. Each module contains 4 fuel tubes bonded to a central heatpipe. Fission energy is conducted from the fuel tubes to the heatpipe, which in turn transfers the energy to a power conversion system. This paper benchmarks a thermal model of the SAFE 30 with actual test data from simulated SAFE 30 module tests. Two "dummy" SAFE 30 modules were fabricated - each consisted of 4 1-inch dia. tubes (simulating the fuel tubes) bonded to a central 1" dia. tube (simulating the heatpipe). In the first module the fuel tubes were simply brazed to the heatpipe along the line of contact (leaving void space in the interstices), and in the second module the tubes and heatpipe were brazed via tricusps that completely fill the interstices between the tubes. In these tests, fission energy is simulated by placing resistance heaters within each of the 4 fuel tubes. The tests were conducted in a vacuum chamber in 4 configurations: tri-cusps filled with and without an outer insulation wrap, and no tri-cusps with and without an outer insulation wrap. The baseline SAFE 30 configuration uses the brazed tri-cusps. During the tests, the power applied to the heaters was varied in a stepwise fashion, until a steady-state temperature profile was reached. These temperature levels varied between 773 K and 1073 K. To benchmark the thermal model, the input energy and chamber surface temperature were used as boundary conditions for the model. The analytical results from the nodes at the same location as the test thermocouples were plotted again test data to determinate the accuracy of the analysis. The unknown variables on the analysis are the radiation emissivity of the pipe and chamber and the radiation view factor between the module and the chamber. A correlation was determined using a parametric analysis by varying the surface emissivity and view factor until a good match was reached. This model and the corresponding data will later be used to evaluate the heat transfer characteristics of the SAFE 30 core, and perform various design trade-offs. Finally, the test data is evaluated to determine the effect of the tri-cusp insert on heat transfer. It is found that the tri-cusps cause a significant increase in module heat transfer. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35806 USA. RP Roman, J (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35806 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 849 EP 853 PG 5 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300122 ER PT S AU Godfroy, T Ring, P Patton, B Houts, M Pedersen, K AF Godfroy, T Ring, P Patton, B Houts, M Pedersen, K BE ElGenk, MS TI Mechanism to ensure safety of fission system during launch SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The potential for fission-based propulsion systems in opening the solar system to extensive exploration, development, and settlement has been recognized for decades. Work toward a first-generation flight demonstrator is underway at MSFC. Safety is one of the main concerns in the planning, development, and design of the system. The purpose of this research is to design, fabricate, and test a mechanism that will (1) enable complete separation of high reactivity worth nuclear fuel elements from the reactor core during launch and (2) enable reliable insertion of these elements into the core immediately prior to reactor startup. The mechanism will preclude any potential for inadvertent reactor startup during a launch accident. The mechanism thus represents one option for ensuring that the launch of space fission systems is fully safe. Early in the concept phase it became clear that there were many different ways to accomplish fuel separation followed by in-space insertion. The benefits of each method ultimately depended on the overall system (spacecraft or otherwise) design and the mission requirements or uses for the reactor. It became evident that since this information was not yet available thee best solution would be to provide multiple designs and let the mission and spacecraft requirements dictate which design to use. With this in mind, two different in-space fueling methods were pursued with the available funding. The first method involves placing the nuclear fuel off axis and external to the fuel. The second method involves replacing some of the fuel with a neutron absorber until the reactor is ready to be fueled. Each method has its benefits and constraints that should be balanced with system and mission requirements. C1 NASA, George C Marshall Space Flight Ctr, Prop Res Ctr, Huntsville, AL 35812 USA. RP Godfroy, T (reprint author), NASA, George C Marshall Space Flight Ctr, Prop Res Ctr, Huntsville, AL 35812 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 854 EP 858 PG 5 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300123 ER PT S AU Salvail, PG Reid, RS Ring, PJ AF Salvail, PG Reid, RS Ring, PJ BE ElGenk, MS TI Development of core cladding fabrication techniques for phase I fission propulsion systems SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Phase I fission propulsion systems focus on safety, timely development, and affordability. Prototype and flight units can be tested at full thrust, using resistance heaters to closely simulate heat from a fission reaction. In Phase I ground testing, one goal is to establish a reliable and affordable manufacturing technique for fabricating a flight-like core. A refractory metal (Mo) has been suggested for the core substrate, primarily due to the existence of a significant database for Mo/UO2 fuel. The core can be fabricated by bundling Mo tubes with a bonding system that meets preliminary test goals. These criteria include materials compatibility, ability to maintain thermal and structural integrity during 10,000 hours of operation, and fabrication with existing facilities. This paper describes an effort to investigate several fabrication techniques in a cost-effective manner. First, inexpensive materials were tested at low temperatures to determine the relative effectiveness of such techniques as welding, brazing, plating, and vacuum plasma spraying (VPSing). Promising techniques were chosen for further evaluation, including thermal and structural studies, using ceramic tubing at intermediate temperatures. The most desirable technique will be tested on actual Mo tubing at anticipated operating temperatures. This work is being performed by the National Aeronautics & Space Administration (NASA) at George C. Marshall Space Flight Center (MSFC), Los Alamos National Laboratory (LANL), and Advanced Methods & Materials (AMM), Inc. C1 NASA, George C Marshall Space Flight Ctr, IIT Res Inst, Huntsville, AL 35812 USA. RP Salvail, PG (reprint author), NASA, George C Marshall Space Flight Ctr, IIT Res Inst, Huntsville, AL 35812 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 859 EP 864 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300124 ER PT S AU Emrich, WJ AF Emrich, WJ BE ElGenk, MS TI Gasdynamic mirror fusion propulsion experiment SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Nuclear fusion appears to be the most promising concept for producing extremely high specific impulse rocket engines. One particular fusion concept which seems to be particularly well suited for fusion propulsion applications is the gasdynamic mirror (GDM). This device would, operate at much higher plasma densities and with much larger L/D ratios than previous mirror machines. Several advantages accrue from such a design. First, the high L/D ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of-plasma confinement. Second, the high plasma density will result in the plasma behaving much more like a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with "loss cone" microinstabilities. An experimental GDM device is currently being constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the feasibility of this type of propulsion system. Initial experiments are expected to commence in the late fall of 2000. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Emrich, WJ (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 886 EP 891 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300129 ER PT S AU Martin, J Lewis, R Kramer, K Meyer, K Smith, G AF Martin, J Lewis, R Kramer, K Meyer, K Smith, G BE ElGenk, MS TI Design and preliminary testing of a high performance antiproton trap (HiPAT) SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID CONFINEMENT; PLASMAS; MASS AB Antimatter represents the pinnacle of energy density, offering the potential to enhance current fusion/fission concepts enabling various classes of deep space missions. Current production rates are sufficient to support proof-of-concept evaluation of many key technologies associated with antimatter-derived propulsion. Storage has been identified as a key enabling technology for all antimatter-related operations, and as such is the current focus of this NASA-MSFC effort to design and fabricate a portable device capable of holding up to 10(12) particles. Hardware has been assembled and initial tests are underway to evaluate the trap behavior using electron gun generated, positive hydrogen ions. Ions have been stored for tens of minutes, limited by observed interaction with background gas. Additionally, radio frequency manipulation is being tested to increase lifetime by stabilizing the stored particles, potentially reducing their interaction with background gas, easing requirements on ultimate trap vacuum and precision mechanical alignment. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Martin, J (reprint author), NASA, George C Marshall Space Flight Ctr, TD40, Huntsville, AL 35812 USA. NR 21 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 931 EP 938 PG 8 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300135 ER PT S AU Thieme, LG Schreiber, JG AF Thieme, LG Schreiber, JG BE ElGenk, MS TI Update on the NASA GRC Stirling Technology development project SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB The Department of Energy, NASA Glenn Research Center (GRC), and Stirling Technology Company (STC) are developing a free-piston Stirling convertor for a Stirling radioisotope power system (SRPS) to provide spacecraft on-board electric power for NASA deep space missions. The SRPS has recently been identified for potential use on the Europa Orbiter and Solar Probe Space Science missions. Stirling is also now being considered for unmanned Mars revers. NASA GRC is conducting an in-house project to assist in developing the Stirling convertor for readiness for space qualification and mission implementation. As part of this continuing effort, the Stirling convertor will be further characterized under launch environment random vibration testing, methods to reduce convertor electromagnetic interference (EMI) will be developed, and an independent performance verification will be completed. Convertor life assessment and permanent magnet aging characterization tasks are also underway. Substitute organic materials for the linear alternator and piston bearing coatings for use in a high radiation environment have been identified and have now been incorporated in Stirling convertors built by STC for GRC. Electromagnetic and thermal finite element analyses for the alternator are also being conducted. This paper discusses the recent results and status for this NASA GRC in-house project. C1 NASA, John H Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Thieme, LG (reprint author), NASA, John H Glenn Res Ctr Lewis Field, MS 301-2,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 10 TC 1 Z9 1 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1005 EP 1010 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300148 ER PT S AU Schreiber, JG AF Schreiber, JG BE ElGenk, MS TI Power characteristics of a Stirling radioisotope power system over the life of the mission SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Stirling radioisotope power systems are presently being considered for use on long life deep space missions. Some applications that Stirling technology has been developed for in the past could control the heat input to the engine, as was the case in the Automotive Stirling Engine (ASE) program. The combustion system could change the rate at which fuel was burned in response to the Stirling heater head temperature and the desired set point. In other cases, heat input was not controlled. An example is the solar terrestrial Advanced Stirling Conversion System (ASCS), where the heat input was a function of solar intensity and the performance of the solar concentrator and receiver. The control system for this application would measure the Stirling heater head temperature and throttle the Stirling convertor to once again, maintain the Stirling heater head temperature at the desired set point. In both of these examples, the design was driven to be cost effective. In the Stirling radioisotope power system, the heat generated by the decay in plutonium is reduced with the half-life of the isotope, and the control system must be as simple as possible and still meet the mission requirements. The most simple control system would be one that allows the Stirling power convertor to autonomously change its operating conditions in direct response to the reduced heat input, with no intervention from the control system, merely seeking a new equilibrium point as the isotope decays. This paper presents an analysis of power system performance with this simple control system, which has no feedback and does not actively alter the operating point as the isotope decays. C1 NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Schreiber, JG (reprint author), NASA, Glenn Res Ctr Lewis Field, MS 301-2,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 5 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1011 EP 1016 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300149 ER PT S AU Mason, LS AF Mason, LS BE ElGenk, MS TI A comparison of Brayton and Stirling space nuclear power systems for power levels from 1 kilowatt to 10 megawatts SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB An analytical study was conducted to assess the performance and mass of Brayton and Stirling nuclear power systems for a wide range of future NASA space exploration missions. The power levels and design concepts were based on three different mission classes. Isotope systems, with power levels from 1 to 10 kilowatts, were considered for planetary surface revers and robotic science. Reactor power systems for planetary surface outposts and bases were evaluated from 10 to 500 kilowatts. Finally, reactor power systems in the range from 100 kilowatts to 10 megawatts were assessed for advanced propulsion applications. The analysis also examined the effect of advanced component technology on system performance. The advanced technologies included high temperature materials, lightweight radiators, and high voltage power management and distribution. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Mason, LS (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 10 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1017 EP 1022 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300150 ER PT S AU Wong, WA AF Wong, WA BE ElGenk, MS TI Solar refractive secondary concentrator technology overview SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Refractive secondary concentrators, coupled with advanced primary concentrators, can efficiently convert solar energy to heat for a wide variety of space applications including power generation, thermal propulsion, and furnaces. These applications typically require very high temperatures (as high as 2000 K) and high concentration ratios (10,000 to 1). To enable concentration systems that meet these requirements, the NASA Glenn Research Center is developing the refractive secondary concentrator, which uses refraction and total internal reflection to concentrate and direct solar energy. Presented is an overview of the refractive secondary concentrator technology development effort, including a description of benefits, past accomplishments, and future plans. Highlighted is a recent proof-of-concept test of a prototype sapphire refractive secondary concentrator performed in a solar vacuum environment that demonstrated throughput efficiency of 87%. It is anticipated that the application of an optical coating to the inlet surface of the refractive secondary to reduce the reflection losses at this surface can improve the throughput efficiency to 93%. Plans to conduct additional solar thermal vacuum tests to demonstrate high temperatures and high throughput power are also presented (up to 2000 K and 5 kW). C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Wong, WA (reprint author), NASA, Glenn Res Ctr, 21000 Brookpark Rd, Cleveland, OH 44135 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1023 EP 1028 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300151 ER PT S AU Schreiber, JG AF Schreiber, JG BE ElGenk, MS TI A comparative reliability analysis of free-piston Stirling machines SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB A free-piston Stirling power convertor is being developed for use in an advanced radioisotope power system to provide electric power for NASA deep space missions. These missions are typically long lived, lasting for up to 14 years. The Department of Energy (DOE) is responsible for providing the radioisotope power system for the NASA missions, and has managed the development of the free-piston power convertor for this application. The NASA Glenn Research Center has been involved in the development of Stirling power conversion technology for over 25 years and is currently providing support to DOE. Due to the nature of the potential missions, long life and high reliability are important features for the power system. Substantial resources have been spent on the development of long life Stirling cryocoolers for space applications. As a very general statement, free-piston Stirling power convertors have many features in common with free-piston Stirling cryocoolers, however there are also significant differences. For example, designs exist for both power convertors and cryocoolers that use the flexure bearing support system to provide noncontacting operation of the close-clearance moving parts. This technology and the operating experience derived from one application may be readily applied to the other application. This similarity does not pertain in the case of outgassing and contamination. In the cryocooler, the contaminants normally condense in the critical heat exchangers and foul the performance. In the Stirling power convertor just the opposite is true as contaminants condense on non-critical surfaces. A methodology was recently published that provides a relative comparison of reliability, and is applicable to systems. The methodology has been applied to compare the reliability of a Stirling cryocooler relative to that of a free-piston Stirling power convertor. The reliability analysis indicates that the power convertor should be able to have superior reliability compared to the cryocooler. C1 NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Schreiber, JG (reprint author), NASA, Glenn Res Ctr Lewis Field, 21000 Brookpark Rd, Cleveland, OH 44135 USA. NR 15 TC 0 Z9 0 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1041 EP 1046 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300154 ER PT S AU Williams, RM Shields, VB Homer, ML Kisor, AK Ryan, MA AF Williams, RM Shields, VB Homer, ML Kisor, AK Ryan, MA BE ElGenk, MS TI Challenges facing successful development of long life, high temperature, high efficiency/power AMTECs for space applications SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP Conference Proceedings LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID METAL THERMOELECTRIC CONVERTER; INTERFACIAL IMPEDANCE; ELECTRODES; SODIUM; VAPOR; MODEL; DEPENDENCE; TRANSPORT; KINETICS; ALUMINA AB The technical challenges confronting development of Alkali Metal Thermal-to Electric Converters (AMTEC) for up to 15 year life on NASA Mars and outer planetary missions are significant, although approaches to solutions are understood by many investigators. The technical challenges include material issues, specifically involving decomposition of materials or chemical reaction between materials in contact; electrical issues, including electrical shunts that reduce output power and possibly plasma discharges within AMTEC converter units in which potentials in excess of 5.25 Volts exist; and heat and mass transport issues which can have major effects on the converter unit's power and efficiency. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Williams, RM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rmw@jpl.nasa.gov NR 79 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1055 EP 1065 PG 11 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300156 ER PT S AU Shields, VB Williams, RM Ryan, MA Cortez, R Homer, ML Kisor, AK Manatt, K AF Shields, VB Williams, RM Ryan, MA Cortez, R Homer, ML Kisor, AK Manatt, K BE ElGenk, MS TI Mathematical modeling of the impedance of single and multi-cell AMTEC units SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID INTERFACIAL IMPEDANCE; ELECTRODES; TRANSPORT; KINETICS AB AMTEC power systems are designed for use on extended space missions. During the lifetime of such missions the power available for the spacecraft will depend on the degradation of the system performance. Development of a tool that allows monitoring of the system degradation will provide an aid in determining the condition of the power source. Since the power output is a function of the impedance across the BASE tube and electrodes, monitoring its variation can provide an understanding of the internal changes within the AMTEC unit. A lumped element impedance model is being developed for a single electrochemical cell and a six electrochemical cell AMTEC unit. The analysis was performed using the symbolic analysis software program, Mathematica. The model examines the cathode-BASE-anode impedance by allowing the BASE and the electrode-BASE interfaces to be depicted as a combination of resistances, Warburg impedances and pseudo capacitances (i.e. constant phase elements). The model results are compared with operational measurements from single and six electrochemical cell AMTEC units tested for more than 1000 hours. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Shields, VB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1082 EP 1087 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300159 ER PT S AU Ryan, MA Williams, RM Lara, L Fiebig, BG Cortez, RH Kisor, AK Shields, VB Homer, ML AF Ryan, MA Williams, RM Lara, L Fiebig, BG Cortez, RH Kisor, AK Shields, VB Homer, ML BE ElGenk, MS TI Advances in electrode materials for AMTEC SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID METAL THERMOELECTRIC CONVERTER; POROUS MOLYBDENUM ELECTRODES; INTERFACIAL IMPEDANCE; TRANSPORT; KINETICS; ALUMINA AB A mixed conducting electrode for the Alkali Metal Thermal to Electric Converter (AMTEC) has been made and tested. The electrode is made from a slurry of metal and TiO2 powders which is applied to the electrolyte and fired to sinter the electrode material. During the first 48-72 hours of operation in a SETC, the electrode takes up Na from low pressure sodium vapor to make a metal-Na-Ti-O compound. This compound is electronically conducting and ionically conducting to sodium; electronic conduction is also provided by the metal in the electrode. With a mixed conducting electrode made from robust, low vapor pressure materials, the promise for improved performance and lifetime is high. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ryan, MA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 22 TC 6 Z9 6 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1088 EP 1093 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300160 ER PT S AU Shields, VB Kisor, AK Fiebig, B Williams, RM Ryan, MA Homer, ML AF Shields, VB Kisor, AK Fiebig, B Williams, RM Ryan, MA Homer, ML BE ElGenk, MS TI Metallurgical examination of an AMTEC unit SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Two AMTEC units were operated for over 300 hours and then dissected and examined. The converter units were fabricated by Advanced Modular Power Systems, inc. using a cold end condenser manufactured by Creare, Inc. and were constructed with a stainless steel housing and stainless steel sheathed molybdenum wick. Creare Unit 1 operated for 342 hours with condenser and BASE tube cell temperatures of 663 K and 1003 K respectively; the output power varied from an initial 68 mw to a final 25 mw. Operation of Creare Unit 1 was halted due to a low initial output current and power that remained unchanged. Creare Unit 2 ran for 575 hours with condenser and BASE tube cell temperatures of 543 K and 978 K respectively; the output power varied from an initial 2.6 watts to a final 1.8 watts. Operation of Creare Unit 2 was halted due to a low power output after the heater unit supplying heat failed and was replaced. The expected output power for both units was about 1 to 4 watts. Both units were subsequently disassembled and dissected to determine a failure mechanism and analyze the internal sodium distribution. Analysis showed that the internal sodium was primarily distributed near the condenser end of the converter units extending out to a distance of 3.2 cm. No significant amounts of sodium deposits were observed in the BASE tubes or plenum of either converter unit. The wick was sliced into 2 to 3 mm sections and analyzed using a SEM and X-tay florescence to determine its sodium distribution. The sodium distribution along the wick from the condenser to the base of the evaporator was observed to be continuous throughout. The analysis however could not determine how the sodium flow varied during operation. The low power output of Creare Unit 1 and the final low power output of Creare Unit 2 was tentatively determined to result from a fracture of the structural joint at the BASE tube braze seal on several of the tubes. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Shields, VB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 1 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1094 EP 1099 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300161 ER PT S AU Williams, RM Kisor, AK Homer, ML Manatt, K Shields, BV Ryan, MA AF Williams, RM Kisor, AK Homer, ML Manatt, K Shields, BV Ryan, MA BE ElGenk, MS TI Reactivity of thin metal films on sodium beta'' alumina ceramic in high temperature, low pressure sodium vapor SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP Conference Proceedings LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID THERMOELECTRIC CONVERTER; INTERFACIAL IMPEDANCE; AMTEC ELECTRODES; CONVERSION; TRANSPORT; KINETICS AB Electrochemical techniques including impedance spectroscopy are routinely used to test the performance of AMTEC electrodes. These experiments may be carried out in an actual AMTEC cell, or in an sodium exposure test cell SETC where the sodium pressure and the temperature are identical at both the anode and cathode. These tests reveal details of electrode material grain growth, electrode decomposition and reaction of electrode materials with the sodium beta " alumina solid electrolyte. Tests of the same sort may be used to examine the compatibility of metals and sodium beta " alumina under simulated AMTEC operating conditions. Preliminary tests comparing rhodium/tungsten, molybdenum, titanium and vanadium electrodes are reported. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Williams, RM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rmw@jpl.nasa.gov NR 34 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1100 EP 1106 PG 7 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300162 ER PT S AU Caillat, T Borshchevsky, A Snyder, J Fleurial, JP AF Caillat, T Borshchevsky, A Snyder, J Fleurial, JP BE ElGenk, MS TI High efficiency segmented thermoelectric unicouples SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Highly efficient, segmented thermoelectric unicouple incorporating advanced thermoelectric materials with superior thermoelectric figures of merit are currently being developed at the Jet Propulsion Laboratory (JPL). These segmented unicouples incorporate a combination of state-of-the-art thermoelectric materials based on Bi2Te3 and novel p-type Zn4Sb3, p-type CeFe4Sb12-based alloys and n-type CoSb3-based alloys developed at JPL. They can be integrated into thermoelectric power generation modules which could be used for a variety of applications making use of waste heat recovery and also potentially in Radioisotope Power Systems (RPSs) that are needed for several NASA missions planned over the next few years. These missions call for electrical power requirements ranging from 20 to 200 watts and 6 to 15 years mission duration. The resulting RPSs would not only have a high specific power (similar to8 We/kg) that is about twice that of the state-of-the-art Radioisotope Thermoelectric Generators (RTGs), but also a higher overall efficiency (> 14%), halving the 238PuO(2) needed for a given electric power requirement. These advanced RPSs would couple the novel, segmented thermoelectric unicouples (STUs) to one or several standard General Purpose Heat Source (GPHS) modules (or bricks), depending on the electric power requirements. The advanced STUs would operate at a hot side temperature of about 1000 K, alleviating some of the concerns associated with the high temperature operation of current GPHS-RTGs (similar to 1300K), and at a cold side temperature of similar to 400 K. The latest developments in the fabrication and testing of the advanced segmented thermoelectric unicouples are presented and discussed. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Caillat, T (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Snyder, G. Jeffrey/E-4453-2011 OI Snyder, G. Jeffrey/0000-0003-1414-8682 NR 6 TC 10 Z9 10 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1107 EP 1112 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300163 ER PT S AU Badhwar, GD O'Neill, PM Troung, AG AF Badhwar, GD O'Neill, PM Troung, AG BE ElGenk, MS TI Galactic cosmic radiation environment models SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB Models of the radiation environment in free space and in near earth orbits are required to estimate the radiation dose to the astronauts for Mars, Space Shuttle, and the International Space Station missions, and to estimate the rate of single event upsets and latch-ups in electronic devices. Accurate knowledge of the environment is critical for the design of optimal shielding during both the cruise phase and for a habitat on Mars or the Moon. Measurements of the energy spectra of galactic cosmic rays (GCR) have been made for nearly four decades. In the last decade, models have been constructed that can predict the energy spectra of any GCR nuclei to an accuracy of better than 25%. Fresh and more accurate measurements have been made in the last year. These measurements can lead to more accurate models. Improvements in these models can be made in determining the local interstellar spectra and in predicting the level of solar modulation. It is the coupling of the two that defines a GCR model. This paper reviews of two of the more widely used models, and a comparison of their predictions with new proton and helium data from the Alpha Magnetic Spectrometer (AMS), and spectra of beryllium to iron in the similar to 40 to 500 MeV/n acquired by the Advanced Composition Explorer (ACE) during the 1997-98 solar minimum. Regressions equations relating the IMP-8 helium count rate to the solar modulation deceleration parameter calculated using the Climax neutron monitor rate have been developed and may lead to improvements in the predictive capacity of the models. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Badhwar, GD (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1179 EP 1184 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300174 ER PT S AU Reames, DV Tylka, AJ Ng, CK AF Reames, DV Tylka, AJ Ng, CK BE ElGenk, MS TI Solar energetic particles and space weather SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID TEMPORAL EVOLUTION; EVENTS; ACCELERATION; WAVES; TIME AB The solar energetic particles (SEPs) of consequence to space weather are accelerated at shock waves driven out from the Sun by fast coronal mass ejections (CMEs). In the large events, these great shocks fill half of the heliosphere. SEP intensity profiles change appearance with longitude. Events with significant intensities of > 10 MeV protons occur at an average rate of similar to 13 yr(-1) near solar maximum and several events with high intensities of > 100 MeV protons occur each decade. As particles stream out along magnetic field lines from a shock near the Sun, they generate waves that scatter subsequent particles. At high intensities, wave growth throttles the flow below the "streaming limit." However, if the shock maintains its strength, particle intensities can rise above this limit to a peak when the shock itself passes over the observer creating a 'delayed' radiation hazard, even for protons with energies up to similar to1 GeV. The streaming limit makes us blind to the intensities at the oncoming shock, however, heavier elements such as He, O, and Fe probe the shape of the wave spectrum, and variation in abundances of these elements allow us to evade the limit and probe conditions at the shock, with the aid of detailed modeling. At high energies, spectra steepen to form a spectral 'knee'. The location of the proton spectral knee can vary from similar to 10 MeV to similar to1 GeV, depending on shock conditions, greatly affecting the radiation hazard. Hard spectra are a serious threat to astronauts, placing challenging requirements for shielding, especially on long-duration missions to the moon or Mars. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Reames, DV (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. RI Tylka, Allan/G-9592-2014 NR 16 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1185 EP 1190 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300175 ER PT S AU Ansari, RR Giblin, FJ King, JF AF Ansari, RR Giblin, FJ King, JF BE ElGenk, MS TI Non-invasive, quantitative, and remote detection of early radiation cataracts for applications in bio-astronautics and bio-informatics SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program ID PROTEIN DIFFUSIVITY; RABBIT; LENS; PROBE AB Human exploration of Mars may be a possibility in the next twenty years. Maintaining good vision is an essential aspect of achieving a successful mission. Continuous radiation exposure is a risk factor for radiation-induced cataracts in astronauts. A compact device based on the technique of dynamic light scattering (DLS) is designed for monitoring an astronaut's ocular health during long-duration space travel. Preliminary data on the simulated effects of ionizing radiation exposure to the ocular tissues of nan-human animals and results on the sensitivity of DLS over established clinical procedures in investigating cataracts are presented. This capability of early diagnosis, unmatched by any other clinical technique in use today, may enable prompt initiation of preventive/curative therapy. An inter-net web based system integrating photon correlation data and controlling the hardware to monitor cataract development in vivo at a remote site in real time (tele-ophthalmology) is currently being developed. Cataract studies on-board the international Space Station (ISS) will be helpful in designing better protective radiation shields for future space vehicles and space suits. C1 NASA, Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Cleveland, OH 44135 USA. RP Ansari, RR (reprint author), NASA, Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Mail Stop 333-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1224 EP 1229 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300181 ER PT S AU Wilson, T Pinsky, L Carminati, F Brun, R Ferrari, A Sala, P Empl, A MacGibbon, J AF Wilson, T Pinsky, L Carminati, F Brun, R Ferrari, A Sala, P Empl, A MacGibbon, J BE ElGenk, MS TI A Monte Carlo transport code study of the space radiation environment using FLUKA and ROOT SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM-2001 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Space Technology and Applications International Forum (STAIF-2000) on Space Exploration and Transportation - Journey into the Future CY FEB 11-14, 2001 CL ALBUQUERQUE, NM SP US DOE, NASA, Amer Astronaut Soc, AIAA, AIChE, Amer Nucl Soc, Amer Soc Mech, IEEE, Int Astronaut Federat, Inst Space & Nucl Power Studies, NASA Natl Space Grant Coll & Fellowship Program AB We report on the progress of a current study aimed at developing a state-of-the-art Monte-Carlo computer simulation of the space radiation environment using advanced computer software techniques recently available at CERN, the European Laboratory for Particle Physics in Geneva, Switzerland. By taking the next-generation computer software appearing at CERN and adapting it to known problems in the implementation of space exploration strategies, this research is identifying changes necessary to bring these two advanced technologies together. The radiation transport tool being developed is tailored to the problem of taking measured space radiation fluxes impinging on the geometry of any particular spacecraft or planetary habitat and simulating the evolution of that flux through an accurate model of the spacecraft material. The simulation uses the latest known results in low-energy and high-energy physics. The output is a prediction of the detailed nature of the radiation environment experienced in space as well as the thermal neutron albedo and secondary particle albedo created by the spacecraft material itself. Beyond doing the physics transport of the incident flux using a Monte Carlo code called FLUKA, our software tool will provide a self-contained stand-alone object-oriented analysis and visualization infrastructure. The latter is known as ROOT. We will also describe the method for defining spacecraft geometries by utilizing aerospace finite element models (FEMs). C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Wilson, T (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-980-7 J9 AIP CONF PROC PY 2001 VL 552 BP 1234 EP 1239 PG 6 WC Engineering, Aerospace; Thermodynamics; Nuclear Science & Technology SC Engineering; Thermodynamics; Nuclear Science & Technology GA BR99Y UT WOS:000168300300183 ER PT S AU Withbroe, GL AF Withbroe, George L. BE Song, P Singer, HJ Siscoe, GL TI Living With a Star SO SPACE WEATHER SE Geophysical Monograph Series LA English DT Proceedings Paper CT Chapman Conference on Space Weather CY MAR 20-JUN 24, 2001 CL Clearwater, FL AB The goal of the Living With a Star (LWS) program is to develop scientific knowledge and understanding of those aspects of the connected Sun-Earth system that directly affect life and society. The NASA LWS initiative includes four major elements: (1) a Space Weather Research Network of solar-terrestrial spacecraft, (2) a theory, modeling, and data analysis program, (3) Space Environment Testbeds for flight testing radiation-hardened and radiation-tolerant systems in the Earth's space environment, and (4) development of partnerships with national and international agencies and industry. This paper provides a brief overview of the LWS program. C1 NASA Headquarters, Code SA, Off Space Sci, Washington, DC 20546 USA. RP Withbroe, GL (reprint author), NASA Headquarters, Code SA, Off Space Sci, Washington, DC 20546 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0065-8448 BN 978-0-87590-984-4 J9 GEOPH MONOG SERIES PY 2001 VL 125 BP 45 EP 51 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BOP22 UT WOS:000277201400006 ER PT S AU Reames, DV AF Reames, Donald V. BE Song, P Singer, HJ Siscoe, GL TI SEPs: Space Weather Hazard in Interplanetary Space SO SPACE WEATHER SE Geophysical Monograph Series LA English DT Proceedings Paper CT Chapman Conference on Space Weather CY MAR 20-JUN 24, 2001 CL Clearwater, FL ID SOLAR ENERGETIC PARTICLES; EVENTS; ACCELERATION; WAVES; EVOLUTION; SHOCKS; TIME AB In the largest and most hazardous of solar energetic particle (SEP) events, acceleration takes place at shock waves driven out from the Sun by fast CMEs. Multi-spacecraft studies show that the particles from the largest events span more than 180 degrees in solar longitude; the events can last for several days. Protons streaming away from the shock generate waves that trap particles in the acceleration region, limiting outflowing intensities but increasing the efficiency of acceleration to higher energies. Thus, early intensities are bounded, but at the time of shock passage, they can suddenly rise to a peak. These shock peaks extend to >500 MeV in the largest events, creating a serious 'delayed' radiation hazard. At high energies, spectra steepen to form a 'knee.' This spectral knee can vary from similar to 10 MeV to similar to 1 GeV depending on shock conditions, greatly affecting the radiation hazard. Elements with different charge-to-mass ratios differentially probe the wave spectra near shocks, producing abundance ratios that vary in space and time. These abundance ratios are a tool that can foretell conditions at an oncoming shock. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Reames, DV (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. NR 21 TC 12 Z9 12 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0065-8448 BN 978-0-87590-984-4 J9 GEOPH MONOG SERIES PY 2001 VL 125 BP 101 EP 107 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BOP22 UT WOS:000277201400012 ER PT S AU Hathaway, DH Wilson, RM Reichmann, EJ AF Hathaway, David H. Wilson, Robert M. Reichmann, Edwin J. BE Song, P Singer, HJ Siscoe, GL TI Status of Cycle 23 Forecasts SO SPACE WEATHER SE Geophysical Monograph Series LA English DT Proceedings Paper CT Chapman Conference on Space Weather CY MAR 20-JUN 24, 2001 CL Clearwater, FL ID SOLAR-CYCLE; PREDICTION; MINIMUM AB Forecasts for the amplitude of cycle 23 that were reported prior to the start of the cycle covered a full range of values from very small to very large. A forecast reached by the consensus of a panel of forecasters convened at the time of minimum in 1996 [Joselyn et al., 1997] suggested that this cycle would be much larger than average with the smoothed International Sunspot Number reaching a maximum of 160 +/- 30 in the middle of the year 2000. A recent survey of solar cycle prediction techniques [Hathaway et al., 1999] found that the two most reliable techniques for forecasting the cycle prior to its start give similar predictions for this cycle's maximum - 154 +/- 26 and 153 +/- 33. Curve-fitting and regression techniques can be used with some confidence now that cycle 23 is well underway. These techniques indicate a more modest sunspot cycle with a maximum of 114 +/- 10 - only slightly larger than average. The current (July 2000) prediction using the combined predictions from both precursors and curve-fitting gives a cycle amplitude of about 136 +/- 20. This is within the errors given by the consensus and the precursor technique predictions but very close to their lower bounds. C1 [Hathaway, David H.; Wilson, Robert M.; Reichmann, Edwin J.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Hathaway, DH (reprint author), NASA, George C Marshall Space Flight Ctr, Mail Code SD50, Huntsville, AL 35812 USA. EM david.hathaway@msfc.nasa.gov; robert.wilson@msfc.nasa.gov; ed.reichmann@msfc.nasa.gov NR 17 TC 1 Z9 2 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0065-8448 BN 978-0-87590-984-4 J9 GEOPH MONOG SERIES PY 2001 VL 125 BP 195 EP 200 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BOP22 UT WOS:000277201400021 ER PT S AU St Cyr, OC Davila, JM AF St Cyr, O. C. Davila, J. M. BE Song, P Singer, HJ Siscoe, GL TI The STEREO Space Weather Broadcast SO SPACE WEATHER SE Geophysical Monograph Series LA English DT Proceedings Paper CT Chapman Conference on Space Weather CY MAR 20-JUN 24, 2001 CL Clearwater, FL ID CORONAL MASS EJECTIONS; LASCO AB The NASA STEREO mission offers exciting possibilities for near-real-time transmission of important measurements for space weather. The STEREO payload will provide solar wind plasma, magnetic field, and energetic particle parameters, as well as optical and radio views of the Sun that cannot be obtained from groundbased observers or spacecraft near Earth. This space weather data will be transmitted continuously from each spacecraft over the X-band frequency (8.4 GHz) at a data rate of about 500 bps. Processing of the space weather broadcast data into useful online displays will be performed at the STEREO Science Center located at Goddard Space Flight Center. NASA will provide for partial coverage from each spacecraft through the Deep Space Network, and we are looking for partners who have ground stations to provide complementary coverage. We anticipate that these data will be very useful to forecasters of space environment conditions. C1 [St Cyr, O. C.; Davila, J. M.] NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. RP St Cyr, OC (reprint author), NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0065-8448 BN 978-0-87590-984-4 J9 GEOPH MONOG SERIES PY 2001 VL 125 BP 205 EP 209 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BOP22 UT WOS:000277201400023 ER PT S AU Tsyganenko, NA AF Tsyganenko, N. A. BE Song, P Singer, HJ Siscoe, GL TI Empirical Magnetic Field Models for the Space Weather Program SO SPACE WEATHER SE Geophysical Monograph Series LA English DT Proceedings Paper CT Chapman Conference on Space Weather CY MAR 20-JUN 24, 2001 CL Clearwater, FL ID SOLAR-WIND CONTROL; GEOMAGNETIC-FIELD; CURRENT SHEET; MAGNETOSPHERE; MAGNETOPAUSE; LOCATION; GEOTAIL; SHAPE AB A brief review is presented of the recent progress and the current state of the data-based modeling of the magnetospheric magnetic field. Combining the wealth of the observational data with flexible and realistic models advances our understanding of the dynamics of Earth's magnetic environment. The empirical approach to the modeling not only makes it possible to quantitatively represent the variable magnetosphere, but helps derive from data valuable information on its response to variations in interplanetary conditions. The cornerstones of the empirical modeling are (1) large sets of magnetic field and plasma data, (2) mathematical methods, allowing one to flexibly represent the B-field on a global scale, and (3) parameterization of magnetospheric field sources by the solar wind state variables and ground activity indices. This paper overviews most recent accomplishments made along these lines and discusses ongoing efforts to improve the data-based models; in particular, replicating the highly variable configuration of the magnetotail, introducing more flexible and realistic ring current model, and taking into account the variable shape and size of the magnetopause. Of special importance is the need to develop an improved representation of the high-latitude magnetosphere, including the dynamical large-scale Birkeland currents. Most of these problems can now be tackled, owing to recently devised powerful mathematical techniques, and a large amount of data obtained during several decades of spaceflight. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Tsyganenko, NA (reprint author), NASA, Goddard Space Flight Ctr, Raytheon ITSS Code 690-2, Greenbelt, MD 20771 USA. EM ys2nt@lepvx3.gsfc.nasa.gov RI Tsyganenko, Nikolai/J-7377-2012 OI Tsyganenko, Nikolai/0000-0002-5938-1579 NR 28 TC 3 Z9 3 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0065-8448 BN 978-0-87590-984-4 J9 GEOPH MONOG SERIES PY 2001 VL 125 BP 273 EP 280 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BOP22 UT WOS:000277201400030 ER PT S AU Ely, TA AF Ely, TA BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Optimal orbits, for sparse constellations of mars navigation satellites SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Current ideas for Mars navigation constellations range any where from placing telecom/navigation payloads on orbiters that have a primary mission to gather scientific data, to satellite(s) that are dedicated to a telecom/navigation mission. A common denominator to all the ideas being advanced is that the constellations have a complement that is small in number and provide only discontinuous coverage to Mars surface assets. This contrasts sharply with navigation systems at Earth, such as GPS, that provide continuous, multiple satellite coverage at all Earth surface locations. This study examines orbit selection for small constellations (4 or fewer satellites) at Mars that minimize time to achieve surface position accuracies at specified levels. A genetic algorithm coupled with a computationally efficient navigation metric tool is utilized to conduct the search through the constellation orbit space. The preliminary results indicate that retrograde, mid-altitude (2000 similar to 5000 km) orbits are most efficient. The presented results also quantify the impact that considering orbit error, the largest error contributor, can have on surface asset positioning on a global scale. C1 CALTECH, Jet Prop Lab, Navigat & Mission Design Sect, Pasadena, CA 91109 USA. RP Ely, TA (reprint author), CALTECH, Jet Prop Lab, Navigat & Mission Design Sect, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 25 EP 44 PN 1&2 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700002 ER PT S AU Guinn, JR AF Guinn, JR BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Mars surface asset positioning using in-situ radio tracking SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut ID PATHFINDER AB Previous Mars lander positioning results relied only upon Direct-To-Earth (DTE) radio metric observations. Accuracy improvements required many weeks of observations and ultimately an accuracy floor of about 100m (1sigma) was reached due to limited geometry and uncertainties in the observations. In early 2004, in-situ measurements of the Mars Exploration Rovers will be collected by the Odyssey Orbiter and used to obtain rover position solutions with accuracies of about 10m (1sigma) in three days or less. Rover surface operations will benefit from the improved accuracy and timely availability of solutions. Alternative techniques are available, but have disadvantages such as: no assured landmarks (image triangulation), reduced telemetry data return (orbiter-rover DTE ranging), or complex dual station tracking requirements (Same Beam Interferometry). Thus, this paper primarily addresses positioning performance improvements from in-situ orbiter to rover doppler tracking compared to DTE doppler only. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Guinn, JR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 45 EP 53 PN 1&2 PG 3 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700003 ER PT S AU Johnson, A Klumpp, A Collier, J Wolf, A AF Johnson, A Klumpp, A Collier, J Wolf, A BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Lidar-based hazard avoidance for safe landing on Mars SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Hazard avoidance is a key technology for landing large payloads safely on the surface of Mars. During hazard avoidance a lander uses onboard sensors to detect hazards in the landing zone, autonomously selects a safe landing site, and then maneuvers to the new site. Design of a system for hazard avoidance is facilitated by simulation where trades involving sensor and mission requirements can be explored. This paper describes the algorithms and models that comprise a scanning LIDAR-based hazard avoidance simulation including a terrain generator, a LIDAR model, hazard avoidance algorithms and powered landing guidance algorithms. Preliminary simulation results show, that the proposed hazard avoidance algorithms are effective at detecting hazards and guiding the lander to a safe landing site. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Johnson, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 125-209, Pasadena, CA 91109 USA. NR 6 TC 3 Z9 3 U1 2 U2 2 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 323 EP 337 PN 1&2 PG 3 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700020 ER PT S AU Taylor, AH Bordi, JJ AF Taylor, AH Bordi, JJ BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Approaching small bodies SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut ID ORBITS AB This paper presents analysis of when and how well, on the approach to previously unvisited small bodies, the trajectory-design relevant physical parameters are determined. Quick acquisition of the knowledge of these parameters is required so that the orbital phase of a mission can be designed. We give the modeling assumptions and show covariance analysis results for a variety of conditions on the approach to four classes of small bodies ranging in diameter from 1 to 500 km. Time histories of the knowledge of mass, rotation characteristics, and comet outgassing are given for a variety of approach trajectories. C1 CALTECH, Jet Prop Lab, Navigat & Mission Design Sect, Pasadena, CA 91109 USA. RP Taylor, AH (reprint author), CALTECH, Jet Prop Lab, Navigat & Mission Design Sect, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 727 EP 755 PN 1&2 PG 7 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700048 ER PT S AU Hamilton, C AF Hamilton, C BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Trajectory design and mission analysis of fast, outer solar system travel SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB An analytic model provided comprehensive minimized trip time and maximized payload mass ratio data for propulsion systems of very high specific impulse and specific power (20,000 < I-sp (seconds) < 125,000 and 5 < alpha (kW/kg) < 125) for piloted outer solar system missions. These ranges of propulsion system operating parameters were shown to enable rendezvous missions to the outer planets with trip times of 2 to 8 months and payload mass ratios up to 40%. Rendezvous vs. round trip missions, as well as conjunction vs. opposition missions, were compared. Nonoptimal mission performance data was calculated. A comparison of performance data was made between spacecraft in the motion picture 2001: A Space Odyssey and NASA's cur-rent study of piloted outer planetary spacecraft. C1 NASA, Glen Res Ctr, Cleveland, OH 44135 USA. RP Hamilton, C (reprint author), NASA, Glen Res Ctr, Mail Stop 86-8,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 11 TC 0 Z9 0 U1 0 U2 2 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 823 EP 832 PN 1&2 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700054 ER PT S AU Franz, H AF Franz, H BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Wind lunar backflip and distant prograde orbit implementation SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Since its launch on November 1, 1994, NASA's Interplanetary Physics Laboratory, or WIND spacecraft, has exploited the potential of lunar gravity assist flybys to drastically alter the spacecraft's trajectory, allowing WIND to fly an orbital profile that would have been impossible with reliance on propulsive delta-V (DeltaV) maneuvers alone, To implement the WIND trajectory, each lunar flyby is designed not only to effect the large-scale orbital modifications necessary for initiating the next mission phase, but also to establish the timing and geometry required for subsequent encounters with the Moon. In April 1999, WIND became the first spacecraft to demonstrate the practical mission application of the lunar backflip transfer concept. A second WIND backflip was performed in January 2000. The backflip trajectory employs a pair of close lunar flybys two weeks apart that rotate the orbital line of apsides by roughly 180 degrees. Achieving the same orbital change using solely propulsive DeltaV maneuvers would require more fuel than WIND's entire mission capacity. However, each of WIND's backflips was completed using only a few meters per second of spacecraft DeltaV. In August 2000, WIND's 32nd lunar flyby sent the spacecraft into a Distant Prograde Orbit (DPO), making WIND the first mission to utilize this orbit concept, as well. In the DPO - a periodic solution to Hill's formulation of the restricted three-body problem - the apogees alternately lead and trail the Earth in its orbit about the Sun, allowing the sampling of the solar wind in regions previously unexplored by other space missions. Measurements from WIND's DPO will be correlated with those of the Advanced Composition Explorer (ACE) spacecraft at the Sun-Earth L I libration point to provide a large-scale perspective of the solar wind. C1 NASA, Goddard Space Flight Ctr, Comp Sci Corp, Greenbelt, MD 20771 USA. RP Franz, H (reprint author), NASA, Goddard Space Flight Ctr, Comp Sci Corp, Code 661, Greenbelt, MD 20771 USA. RI Franz, Heather/F-3508-2012 NR 10 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 999 EP 1017 PN 1&2 PG 3 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700064 ER PT S AU Quadrelli, MB AF Quadrelli, MB BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Modeling and dynamics analysis of tethered formations for space interferometry SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB We describe a rather general simulation model used to predict the dynamics and control performance of formations of spacecraft connected by tethers in heliocentric orbit and in low Earth orbit. The primary function of these systems is in Synthetic Aperture Radar for low Earth orbit applications and for Deep Space Interferometry applications. Some numerical results demonstrate the applicability of these models. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Quadrelli, MB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 198-326, Pasadena, CA 91109 USA. NR 8 TC 3 Z9 3 U1 0 U2 2 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 1259 EP 1277 PN 1&2 PG 3 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700080 ER PT S AU Roberts, CE AF Roberts, CE BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Long duration lissajous orbit control for the ACE sun-earth L1 libration point mission SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The Advanced Composition Explorer (ACE) spacecraft represents the third ever NASA mission to fly to and maintain an orbital station about the Sun-Earth L1 collinear libration point located approximately 1.5 (10(6)) km Sun-ward of Earth. Like its predecessors, its mission is solar and solar wind science. Unlike its predecessors, it is the first libration point mission to fly a relatively small-amplitude Lissajous orbit, as opposed to their large-amplitude quasiperiodic halo orbits. C1 NASA, Goddard Space Flight Ctr, Comp Sci Corp, Greenbelt, MD 20771 USA. RP Roberts, CE (reprint author), NASA, Goddard Space Flight Ctr, Comp Sci Corp, Greenbelt, MD 20771 USA. NR 32 TC 3 Z9 3 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 1447 EP 1464 PN 1&2 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700090 ER PT S AU Folta, D Cooley, S Howell, K AF Folta, D Cooley, S Howell, K BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Trajectory design strategies for the NGST L-2 libration point mission SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The Origins' Next Generation Space Telescope (NGST) trajectory design is addressed in light of improved methods for attaining constrained orbit parameters and their control at the exterior collinear libration point, L-2. The use of a dynamical systems approach, state-space equations for initial libration orbit control, and optimization to achieve constrained orbit parameters are emphasized. The NGST trajectory design encompasses a direct transfer and orbit maintenance under a constant acceleration, A dynamical systems approach can be used to provide a biased orbit and stationkeeping maintenance method that incorporates the constraint of a single axis correction scheme. C1 NASA, Goddard Space Flight Ctr, Flight Dynam Anal Branch, Greenbelt, MD 20771 USA. RP Folta, D (reprint author), NASA, Goddard Space Flight Ctr, Flight Dynam Anal Branch, Greenbelt, MD 20771 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 1465 EP 1480 PN 1&2 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700091 ER PT S AU Vincent, MA AF Vincent, MA BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Probability of overlap for footprints of satellites flying in formation SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The general problem of determining footprint overlap for instruments on different platforms was analyzed by determining the formation flying and pointing requirements needed to satisfy the science requirements of the Cloudat and PI-CASSO-CENA missions. A control value of +/-1 km was found to satisfy the requirement of keeping the footprints within 2 km of each other. If the pointing errors are considered as pure random variables this control results in a 71% probability of footprint overlap. However, if the pointing errors a considered to be fixed biases, the difference between the crosstrack bias values must be less than the sum of the footprint half-widths in order to reach the goal of the footprints overlapping 50% of the time. Satisfying this limit has an 81% probability of occurrence. Combining both a bias and various noise levels indicated that the 50% overlap criterion is independent of the noise. For lower bias values the noise decreases the likelihood of overlap but the noise has the opposite effect for higher bias values. The effect of having a tighter control band on the overlap probability was also studied. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Vincent, MA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 301-140L, Pasadena, CA 91109 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 1617 EP 1629 PN 1&2 PG 3 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700100 ER PT S AU Hall, JL Le, AK AF Hall, JL Le, AK BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Aerocapture trajectories for spacecraft with large, towed ballutes SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Large, towed inflatable structures called ballutes, are a potential technology for enabling aerocapture maneuvers of spacecraft at other planets. The ballute provides most of the drag force and energy dissipation during the maneuver and is detached once the desired velocity change has been achieved. A key premise of this concept is that the timing of ballute detachment provides sufficient trajectory modulation capability to enable aerocapture despite atmospheric uncertainties and navigation errors at the target planet. Numerical simulations performed by two independent computer programs for four candidate missions have confirmed this premise and quantified the entry corridor in terms of initial flight path angle and zero-drag periapsis altitude ranges at each planet. A shared result across these missions is that the zero-drag periapse altitude range divided by the density scale height of the atmosphere yields a common value of approximately 2 despite a wide range of entry velocities, spacecraft masses and atmospheric compositions. Another important shared feature is that the aerocapture heating pulse is of short duration with a maximum value of approximately 250 seconds for the most challenging mission. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Hall, JL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 1857 EP 1872 PN 1&2 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700116 ER PT S AU Gabor, MJ Burns, RD McLaughlin, CA AF Gabor, MJ Burns, RD McLaughlin, CA BE DAmario, LA Sackett, LL Scheeres, DJ Williams, BG TI Class of orbits with 24 hour sun exposure SO SPACEFLIGHT MECHANICS 2001, VOL 108, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA 11th Space Flight Mechanics Meeting CY FEB 11-15, 2001 CL Santa Barbara, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB A satellite in an orbital plane that is perpendicular to the Earth, Sun line, will experience 24 hours of continual Sun exposure. It is expected that these continuous Sun exposure (CSE) orbits will be useful for satellite systems in the early phases of operations. That is, continuous Sun exposure provides a type of natural safe mode for charging batteries during boom/panel deployment and attitude acquisition. These orbits are also useful for maintaining solar panel Sun exposure for missions where attitude maneuvering is prohibited and for missions designed for short term solar observations. There is an extension to the design method when a shadow model and the altitude of the orbit are considered. The design criteria is adjusted to account for the altitude of the orbit and a cylindrical shadow model. For a satellite whose orbit plane is not perpendicular to the ecliptic plane, the use of a shadow model requires that when the orbit is behind the Earth, the perpendicular distance to the Earth-Sun line must be greater than the radius of the Earth. For the perpendicular case, the inclination varies with date. At the solstices, the obliquity combines with the inclination to yield a perpendicular orbit at an inclination of less than 67degrees. At the equinoxes, the obliquity does not affect the inclination of the orbit with respect to the ecliptic and the inclination must be 90 deg. When altitude and the shadow model are considered, the allowable inclination range for a satellite at 1000 km altitude to receive continual Sun exposure at the solstice is approximately 36.5degrees to 143.5degrees. C1 US Space Command, Anal Directorate, Peterson AFB, CO 80914 USA. RP Gabor, MJ (reprint author), US Space Command, Anal Directorate, Ste 116,250 S Peterson Blvd, Peterson AFB, CO 80914 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-487-7 J9 ADV ASTRONAUT SCI PY 2001 VL 108 BP 2019 EP 2030 PN 1&2 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BU35L UT WOS:000175747700126 ER PT B AU Lunsford, C Haldorson, L Fujioka, JT Quinn, TJ AF Lunsford, C Haldorson, L Fujioka, JT Quinn, TJ BE Kruse, GH Bez, N Booth, A Dorn, MW Hills, S Lipcius, RN Pelletier, D Roy, C Smith, SJ Witherell, D TI Distribution patterns and survey design considerations of pacific ocean perch (Sebastes alutus) in the Gulf of Alaska SO SPATIAL PROCESSES AND MANAGEMENT OF MARINE POPULATIONS SE LOWELL WAKEFIELD FISHERIES SYMPOSIA SERIES LA English DT Proceedings Paper CT Symposium on Spatial Processes and Management of Marine Populations CY OCT 27-30, 1999 CL ANCHORAGE, AK SP Alaska Dept Fish & Game, N Pacific Fishery Management Council, US Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Alaska Sea Grant Coll Program, Univ Alaska Fairbanks AB In the Gulf of Alaska, a stratified-random trawl survey has been conducted triennially since 1984 to obtain abundance estimates for major groundfish species. There is considerable uncertainty in the survey biomass estimates for Pacific ocean perch (Sebastes alutus) (POP). Using a geographic information system (GIS) and log-linear analyses, survey and commercial fishery data were analyzed to determine POP distribution patterns in the Gulf of Alaska (GOA). The survey and the fishery appear to encounter POP in the same areas throughout the GOA, and POP distribution does not appear to change temporally. Analysis of CPUE data indicates POP exhibit a tightly aggregated distribution pattern which is related to habitat type. The improvement of the survey design, or relative efficiency compared to a random estimate was 65%. Altering the allocation and stratification of the current design may improve the precision of POP biomass estimates but may be limited by the clustered distribution exhibited by POP in the GOA and the need to assess other species. Work is being conducted to evaluate the merits of adaptive cluster sampling for providing improved estimates for rockfish populations. C1 Natl Marine Fisheries Serv, Alaska Fishery Sci Ctr, Auke Bay Lab, Juneau, AK 99801 USA. RP Lunsford, C (reprint author), Natl Marine Fisheries Serv, Alaska Fishery Sci Ctr, Auke Bay Lab, Juneau, AK 99801 USA. NR 29 TC 6 Z9 6 U1 0 U2 0 PU UNIV ALASKA SEA GRANT PI FAIRBANKS PA POB 755040, 205 ONEILL BLDG, FAIRBANKS, AK 99775 USA BN 1-56612-068-3 J9 LOW WAKE FI PY 2001 VL 17 BP 281 EP 302 PG 22 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA BU03H UT WOS:000174771600014 ER PT B AU Kallman, TR AF Kallman, TR BE Ferland, G Savin, DW TI Photoionization modeling codes SO SPECTROSCOPIC CHALLENGES OF PHOTOIONIZED PLASMAS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Photoionized Plasmas 2000 Conference CY NOV 15-18, 2001 CL UNIV KENTUCKY, LEXINGTON, KY SP NASA Appl Informat Syst Res Program HO UNIV KENTUCKY ID ACTIVE GALACTIC NUCLEI; EMISSION-LINE REGIONS; QUASI-STELLAR OBJECTS; DIGITAL SKY SURVEY; HELIUM-LIKE IONS; X-RAY SPECTRUM; CROSS-SECTIONS; CHARGE-TRANSFER; DIELECTRONIC RECOMBINATION; RATE COEFFICIENTS AB I discuss the current status of numerical modeling of nebulae, including a brief list of historical developments and a summary of the assumptions and computational techniques in conventional use. The progress toward the current state of the art is compared to the progress in development of the various tools needed for modeling: computing technology, atomic rates, algorithms, manpower, and scientific motivation. This is then discussed in the context of the likely changes in the near future. C1 NASA, GSFC, High Energy Astrophys Lab, Greenbelt, MD 20874 USA. RP Kallman, TR (reprint author), NASA, GSFC, High Energy Astrophys Lab, Code 662, Greenbelt, MD 20874 USA. NR 98 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-085-4 J9 ASTR SOC P PY 2001 VL 247 BP 175 EP 195 PG 21 WC Astronomy & Astrophysics; Optics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Astronomy & Astrophysics; Optics; Physics; Spectroscopy GA BU54X UT WOS:000176291800018 ER PT B AU Hubeny, I AF Hubeny, I BE Ferland, G Savin, DW TI From escape probabilities to exact radiative transfer SO SPECTROSCOPIC CHALLENGES OF PHOTOIONIZED PLASMAS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Photoionized Plasmas 2000 Conference CY NOV 15-18, 2001 CL UNIV KENTUCKY, LEXINGTON, KY SP NASA Appl Informat Syst Res Program HO UNIV KENTUCKY ID APPROXIMATE LAMBDA-OPERATORS; LINE TRANSFER; EXPANDING ATMOSPHERES; QUADRATURE PERTURBATIONS; ACCURATE SOLUTION; ITERATION METHOD; SCHEME; LINEARIZATION; CONTINUUM; FULL AB The physical basis and the approximations involved in the escape probability methods are discussed, with particular emphasis on their advantages and drawbacks in individual applications. Next, a brief review of the Accelerated Lambda Iteration (ALI) methods is presented and it is outlined how they can be implemented in the current photoionization codes. C1 NASA, Goddard Space Flight Ctr, NOAO, AURA, Greenbelt, MD 20771 USA. RP Hubeny, I (reprint author), NASA, Goddard Space Flight Ctr, NOAO, AURA, Greenbelt, MD 20771 USA. NR 33 TC 9 Z9 9 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-085-4 J9 ASTR SOC P PY 2001 VL 247 BP 197 EP 219 PG 23 WC Astronomy & Astrophysics; Optics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Astronomy & Astrophysics; Optics; Physics; Spectroscopy GA BU54X UT WOS:000176291800019 ER PT B AU Rubin, RH Dufour, RJ Geballe, TR Colgan, SWJ Harrington, JP Lord, SD Liao, AL Levine, DA AF Rubin, RH Dufour, RJ Geballe, TR Colgan, SWJ Harrington, JP Lord, SD Liao, AL Levine, DA BE Ferland, G Savin, DW TI Infrared spectroscopy of atomic lines in gaseous nebulae SO SPECTROSCOPIC CHALLENGES OF PHOTOIONIZED PLASMAS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Photoionized Plasmas 2000 Conference CY NOV 15-18, 2001 CL UNIV KENTUCKY, LEXINGTON, KY SP NASA Appl Informat Syst Res Program HO UNIV KENTUCKY ID EFFECTIVE COLLISION STRENGTHS; FINE-STRUCTURE LINES; PLANETARY-NEBULAE; ORION-NEBULA; IRON PROJECT; EMISSION-LINES; TRANSITIONS; IONS; TEMPERATURE; EXCITATION AB Spectroscopy in the infrared provides a means to assess important properties of the plasma in gaseous nebulae. We present some of our own work that illustrates the need for interactions between the themes of this conference - astronomical data, atomic data, and plasma simulations. We undertook Infrared Space Observatory (ISO) observations with the intent of better understanding the effects of density variations in nebulae, particularly planetary nebulae (PNs), by determining average electron densities from the flux ratios of several fine-structure, IR emission lines. Instead, we are able to ascertain only minor density information because of several instances of the observed line flux ratios being out of range of the theoretical predictions using current atomic data. In these cases, the ISO data cannot presently be used to derive electron density, but rather provide direction for needed improvements in the atomic collision strengths. We have detected an unidentified (uid) strong emission line in an ISO/SWS spectrum of the Orion Nebula. The line has a rest wavelength 2.89350+/-0.00003 mum. A long-slit UKIRT observation confirms the presence of this line and shows that the emission is spatially extended and appears to be coincident with the brightest part of the ionized region. We do not detect the uid line in our SWS02 spectra of any of the several bright PNs which we observed for a comparable time. The need for basic atomic data, in this case wavelengths to aid species identification, is paramount for future progress. We look toward the future with a brief synopsis of upcoming or planned IR missions that promise a significant spectroscopic bearing. The missions (and their instruments) discussed are SIRTF, SOFIA, and HERSCHEL (upcoming) and NGST, GSMT, and SAFIR (planned). C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Rubin, RH (reprint author), NASA, Ames Res Ctr, MS 245-6, Moffett Field, CA 94035 USA. RI Colgan, Sean/M-4742-2014 NR 32 TC 9 Z9 9 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-085-4 J9 ASTR SOC P PY 2001 VL 247 BP 479 EP 498 PG 20 WC Astronomy & Astrophysics; Optics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Astronomy & Astrophysics; Optics; Physics; Spectroscopy GA BU54X UT WOS:000176291800044 ER PT B AU Gull, TR Ishibashi, K AF Gull, TR Ishibashi, K BE Ferland, G Savin, DW TI Spatially-resolved spectroscopy of Eta Carinae and its ejecta using STIS SO SPECTROSCOPIC CHALLENGES OF PHOTOIONIZED PLASMAS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Photoionized Plasmas 2000 Conference CY NOV 15-18, 2001 CL UNIV KENTUCKY, LEXINGTON, KY SP NASA Appl Informat Syst Res Program HO UNIV KENTUCKY AB Improved experimental capabilities always provide significant new insight to astrophysical problems. The Space Telescope Imaging Spectrograph (STIS), a second-generation instrument within the Hubble Space Telescope has merged good spectral resolution with near-diffraction-limited imagery, The ejecta surrounding the very massive Luminous Blue Variable, Eta Carinae, can now be studied with greatly increased detail. The STIS extended aperture spectroscopy is providing much information on the geometry and physical conditions of the complex ejecta. The data has revealed quite a number of puzzling results that will require much additional spectroscopic interpretation and modeling for improved understanding. For the low-ionization states of many heavy elements, new measurements of energy levels, and their lifetimes are needed to fully explain these results. C1 NASA, Goddard Space Flight Ctr, LASP, Greenbelt, MD 20771 USA. RP Gull, TR (reprint author), NASA, Goddard Space Flight Ctr, LASP, Greenbelt, MD 20771 USA. RI Gull, Theodore/D-2753-2012 OI Gull, Theodore/0000-0002-6851-5380 NR 8 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-085-4 J9 ASTR SOC P PY 2001 VL 247 BP 503 EP 510 PG 8 WC Astronomy & Astrophysics; Optics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Astronomy & Astrophysics; Optics; Physics; Spectroscopy GA BU54X UT WOS:000176291800046 ER PT B AU Kraemer, SB Crenshaw, DM AF Kraemer, SB Crenshaw, DM BE Ferland, G Savin, DW TI The kinematics and physical conditions in the narrow-line regions of the Seyfert galaxies NGC 1068 and NGC 4151 SO SPECTROSCOPIC CHALLENGES OF PHOTOIONIZED PLASMAS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Photoionized Plasmas 2000 Conference CY NOV 15-18, 2001 CL UNIV KENTUCKY, LEXINGTON, KY SP NASA Appl Informat Syst Res Program HO UNIV KENTUCKY ID LONG-SLIT SPECTROSCOPY; NGC-4151; NGC-1068 AB We have examined the physical conditions in the narrowline regions of the two prototypical Seyfert galaxies, NGC 1068 and NGC 4151, using long slit spectra obtained with the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope (HST) and photoionization models. In both galaxies, we find that the emission-line gas is outflowing radially from the nucleus, and cloud deceleration occurs at similar to 150 pc from the nucleus, probably due to interaction with an ambient medium. Although the emission-line gas is ionized by continuum emission from the active nucleus, there are regions in NGC 1068 which show evidence for an additional source of ionizing radiation. C1 Catholic Univ Amer, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kraemer, SB (reprint author), Catholic Univ Amer, NASA, Goddard Space Flight Ctr, Code 681, Greenbelt, MD 20771 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-085-4 J9 ASTR SOC P PY 2001 VL 247 BP 519 EP 522 PG 4 WC Astronomy & Astrophysics; Optics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Astronomy & Astrophysics; Optics; Physics; Spectroscopy GA BU54X UT WOS:000176291800049 ER PT B AU Cohen, EA AF Cohen, EA BE Demaison, J Sarka, K Cohen, EA TI Millimeter and submillimeter spectroscopy in support of upper atmospheric research SO SPECTROSCOPY FROM SPACE SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Spectroscopy from Space CY OCT 31-NOV 04, 2000 CL BRATISLAVA, SLOVAKIA SP NATO DE millimeter spectroscopy; upper atmosphere; limb sounding ID SPECTRAL-LINE CATALOG; HARMONIC FORCE-FIELD; FAR-INFRARED REGION; ROTATIONAL SPECTRUM; MOLECULAR-PROPERTIES; WAVE SPECTRA; NITRIC-ACID; HYPERFINE INTERACTIONS; NUCLEAR-QUADRUPOLE; DIBROMINE MONOXIDE AB This paper describes the laboratory program in millimeter and submillimeter spectroscopy at the Jet Propulsion Laboratory (JPL). The program directly supports ongoing and developing held measurement programs; in particular, the Microwave Limb Sounder (MLS) now in orbit aboard the Upper Atmospheric Research Satellite (UARS), the balloon borne Submillimeter Limb Sounder (SLS), the Far Infrared Limb Observing Spectrometer (FILOS), the 2.5 THz balloon OW spectrometer (BOH), and the MLS to be flown in 2002 on the Earth Observing System (EOS) AQUA platform. This program provides frequencies, linewidths and transition moments for species sought by the observing program, which have promise of being observed by instrumentation being developed by NASA, and which improved atmospheric models indicate are important. These data along with pertinent data available from other sources are analyzed and the results made available to the user community via the JPL "Microwave, Millimeter, and Submillimeter Spectral Line Catalog." From these data, accurate brightness temperatures and line profiles can be obtained. In addition, this program supplies necessary microwave through far infrared data that aid in the interpretation and assignment of infrared and optical spectra of importance to stratospheric research. Particular attention is paid to molecules whose high resolution infrared spectra are contained in the JPL and HITRAN infrared databases and to transient species relevant to research being done by the JPL kinetics group. This program has also been concerned with the determination of molecular structures and other molecular properties of halogen oxides and ore-acids which affect chemical reactivity. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Cohen, EA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 88 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6992-0 J9 NATO SCI SER II MATH PY 2001 VL 20 BP 59 EP 71 DI 10.1017/CBO9780511642333.003 PG 13 WC Engineering, Aerospace; Meteorology & Atmospheric Sciences; Spectroscopy SC Engineering; Meteorology & Atmospheric Sciences; Spectroscopy GA BS37M UT WOS:000169678100004 ER PT S AU Des Marais, DJ AF Des Marais, DJ BE Valley, JW Cole, DR TI Isotopic evolution of the biogeochemical carbon cycle during the Precambrian SO STABLE ISOTOPE GEOCHEMISTRY SE Reviews in Mineralogy & Geochemistry LA English DT Review ID IRON-FORMATION DEPOSITION; ORGANIC-CARBON; TRANSVAAL SUPERGROUP; ATMOSPHERIC OXYGEN; SOUTH-AFRICA; MOLECULAR FOSSILS; CONTINENTAL-CRUST; PROTEROZOIC EON; BILLION YEARS; EARLY EARTH C1 NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. RP Des Marais, DJ (reprint author), NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. NR 110 TC 36 Z9 38 U1 4 U2 22 PU MINERALOGICAL SOC AMER PI CHANTILLY PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA SN 1529-6466 BN 0-939950-55-3 J9 REV MINERAL GEOCHEM JI Rev. Mineral. Geochem. PY 2001 VL 43 BP 555 EP 578 DI 10.2138/gsrmg.43.1.555 PG 24 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA BT79K UT WOS:000174072300010 ER PT B AU Draper, SL Lerch, BA Pereira, JM Nathal, MV Nazmy, MY Staubli, M Clemens, DR AF Draper, SL Lerch, BA Pereira, JM Nathal, MV Nazmy, MY Staubli, M Clemens, DR BE Hemker, KJ Dimiduk, DM Clemens, H Darolia, R Inui, H Larsen, JM Sikka, VK Thomas, M Whittenberger, JD TI Effect of impact damage on the fatigue response of tial alloy-ABB-2 SO STRUCTURAL INTERMETALLICS 2001 LA English DT Proceedings Paper CT 3rd International Symposium on Structural Intermetallics (IS SI) CY SEP 23-27, 2001 CL JACKSON HOLE, WY SP Minerals, Met & Mat Soc, Struct Mat Div ID ALLOY AB The ability of gamma-TiAl to withstand potential foreign or domestic object damage is a technical risk to the implementation of gamma-TiAl in low pressure turbine (LPT) blade applications. In the present study, the impact resistance of TiAl alloy ABB-2 was determined and compared to the impact resistance of Ti-48AI-2Nb-2Cr [1], Specimens were impacted with four different impact conditions with impact energies ranging from 0.22 to 6.09 J. After impacting, the impact damage was characterized by crack lengths on both the front and backside of the impact. Due to the flat nature of gamma -TiAl's S-N (stress vs. cycles to failure) curve, step fatigue tests were used to determine the fatigue strength after impacting, Impact damage increased with increasing impact energy and led to a reduction in the fatigue strength of the alloy. For similar crack lengths, the fatigue strength of impacted ABB-2 was similar to the fatigue strength of impacted Ti-48Al-2Nb-2Cr [1], Similar to Ti-48Al-2Nb-2Cr, ABB-2 showed a classical mean stress dependence on fatigue strength. The fatigue strength of impacted ABB-2 could be accurately predicted using a threshold analysis, In fact, it is the fatigue threshold, not tensile properties, which determines the post-impact fatigue strength. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Draper, SL (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 14 TC 4 Z9 4 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-511-5 PY 2001 BP 295 EP 304 PG 10 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA BT48V UT WOS:000173131100034 ER PT B AU Whittenberger, JD Raj, SV Locci, IE Salem, JA AF Whittenberger, JD Raj, SV Locci, IE Salem, JA BE Hemker, KJ Dimiduk, DM Clemens, H Darolia, R Inui, H Larsen, JM Sikka, VK Thomas, M Whittenberger, JD TI Effects of minor alloying additions on the microstructure, toughness and creep strength of directionally solidified NiAl-31Cr-3Mo SO STRUCTURAL INTERMETALLICS 2001 LA English DT Proceedings Paper CT 3rd International Symposium on Structural Intermetallics (IS SI) CY SEP 23-27, 2001 CL JACKSON HOLE, WY SP Minerals, Met & Mat Soc, Struct Mat Div ID IN-SITU COMPOSITES; MECHANICAL-PROPERTIES; PLASTIC-FLOW; NIAL-CR; BEHAVIOR; SYSTEMS AB A study of the effects of small (0.25 to 1.0 at %) fifth element additions to the structure and mechanical properties of directionally solidified (DS) NiAl-31Cr-3Mo has been undertaken. Essentially all the additions changed the as-DS'ed microstructure from lamellar eutectic grains to cells and, in some case, introduced NiAl dendrites and/or third phases. In general the alloying additions did not improve strength or toughness over that possessed by the base composition; only Hf and, perhaps Ti, gave a minor increase in elevated temperature creep resistance. The lack of improvement in creep properties is probably due to inability to precipitation harden NiAl. C1 NASA, Glenn Res Ctr, CWRU, Cleveland, OH 44135 USA. RP Whittenberger, JD (reprint author), NASA, Glenn Res Ctr, CWRU, Cleveland, OH 44135 USA. NR 27 TC 4 Z9 4 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-511-5 PY 2001 BP 775 EP 784 PG 10 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA BT48V UT WOS:000173131100087 ER PT B AU Raj, SV Locci, IE Whittenberger, JD AF Raj, SV Locci, IE Whittenberger, JD BE Hemker, KJ Dimiduk, DM Clemens, H Darolia, R Inui, H Larsen, JM Sikka, VK Thomas, M Whittenberger, JD TI Development and evaluation of directionally-solidified NiAl(Cr,Mo)-based eutectic alloys for airfoil applications SO STRUCTURAL INTERMETALLICS 2001 LA English DT Proceedings Paper CT 3rd International Symposium on Structural Intermetallics (IS SI) CY SEP 23-27, 2001 CL JACKSON HOLE, WY SP Minerals, Met & Mat Soc, Struct Mat Div ID ROD-PLATE TRANSITION; NIAL-CR; COMPOSITES; BEHAVIOR AB The results of recent efforts to develop directionally-solidified alloys based on the Ni-33Al-31Cr-3Mo eutectic composition are discussed. These developmental efforts included studying the effects of macroalloying and growth rates on microstructure formation as well as the elevated temperature compressive and tensile properties of these alloys. These observations revealed that contrary to conventional opinion, the cellular microstructure was stronger and tougher than the planar eutectic microstructure due to a microstructural refinement of the cell size and interlamellar spacing. The high temperature strengths of these alloys are compared with those of commercial superalloys and advanced NiAl single crystals. The implications of this research on airfoil manufacturing and applications are discussed. C1 NASA, Glenn Res Ctr, CWRU, Cleveland, OH 44135 USA. RP Raj, SV (reprint author), NASA, Glenn Res Ctr, CWRU, Cleveland, OH 44135 USA. NR 25 TC 4 Z9 4 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-511-5 PY 2001 BP 785 EP 794 PG 10 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA BT48V UT WOS:000173131100088 ER PT S AU Seo, ES Wang, JZ Matsunaga, H Anraku, K Imori, M Makida, Y Matsumoto, H McDonald, FB Mitchell, J Moiseev, A Motoki, M Nishimura, J Nozaki, M Orito, S Ormes, JF Otoba, M Saeki, T Sanuki, T Streitmatter, RE Suzuki, J Tanaka, K Ueda, I Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K AF Seo, ES Wang, JZ Matsunaga, H Anraku, K Imori, M Makida, Y Matsumoto, H McDonald, FB Mitchell, J Moiseev, A Motoki, M Nishimura, J Nozaki, M Orito, S Ormes, JF Otoba, M Saeki, T Sanuki, T Streitmatter, RE Suzuki, J Tanaka, K Ueda, I Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K BE Culhane, JL Doyle, G Bentley, RD Wilkes, RJ TI Spectra of H and He measured in a series of annual flights SO SUN AND SIMILAR STARS/COSMIC RAY SPECTRA AND COMPOSITION SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E2 4 and E1 5 Symposia of COSPAR-Scientific-Commission-E held at the 32nd COSPAR Scientific Assembly CY JUL, 1998 CL NAGOYA, JAPAN SP COSPAR ID HELIUM AB We have obtained the absolute spectra of H and He by analyzing data collected by a series of annual flights of the Balloon borne Experiment with a Superconducting solenoid Spectrometer payload. This instrument is configured with a cylindrical magnet, a Time-of-Flight system, a set of cylindrical multiwire drift chambers inside and outside the magnet, and a central tracking device Jet chamber. The analysis involves Monte Carlo simulations of the effective geometry factor, studies of various efficiencies, and corrections for the ionization energy loss, attenuation and atmospheric secondaries. Variations of the H and He fluxes at different levels of solar modulation are presented. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Maryland, Inst Phys Sci & Tech, College Pk, MD 20742 USA. Univ Tokyo, Bunkyo Ku, Tokyo 113, Japan. Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Kobe Univ, Kobe, Hyogo, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 229, Japan. RP Seo, ES (reprint author), Univ Maryland, Inst Phys Sci & Tech, College Pk, MD 20742 USA. RI MOTOKI, Masakazu/B-4212-2009 NR 4 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 26 IS 11 BP 1831 EP 1834 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS67K UT WOS:000170800600019 ER PT S AU Orito, S Maeno, T Matsunaga, H Abe, K Anraku, K Asaoka, Y Fujikawa, M Imori, M Ishino, M Makida, Y Matsui, N Matsumoto, H Mitchell, J Mitsui, T Moiseev, A Motoki, M Nishimura, J Nozaki, M Ormes, J Saeki, T Sanuki, T Sasaki, M Seo, ES Shikaze, Y Sonoda, T Streitmatter, R Suzuki, J Tanaka, K Ueda, I Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K AF Orito, S Maeno, T Matsunaga, H Abe, K Anraku, K Asaoka, Y Fujikawa, M Imori, M Ishino, M Makida, Y Matsui, N Matsumoto, H Mitchell, J Mitsui, T Moiseev, A Motoki, M Nishimura, J Nozaki, M Ormes, J Saeki, T Sanuki, T Sasaki, M Seo, ES Shikaze, Y Sonoda, T Streitmatter, R Suzuki, J Tanaka, K Ueda, I Yajima, N Yamagami, T Yamamoto, A Yoshida, T Yoshimura, K BE Culhane, JL Doyle, G Bentley, RD Wilkes, RJ TI Precision measurement of antiproton spectrum with BESS SO SUN AND SIMILAR STARS/COSMIC RAY SPECTRA AND COMPOSITION SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E2 4 and E1 5 Symposia of COSPAR-Scientific-Commission-E held at the 32nd COSPAR Scientific Assembly CY JUL, 1998 CL NAGOYA, JAPAN SP COSPAR ID COSMIC-RAY ANTIPROTONS; SOLAR MINIMUM; BLACK-HOLES; FLUX AB The absolute fluxes of the cosmic-ray antiproton are measured at solar minimum in the energy range 0.2 to 3.2 GeV, based on 460 antiprotons unambiguously detected by BESS spectrometer during its '95 and '97 balloon flights from Lynn Lake, Canada. In the resultant antiproton spectrum we have detected a clear peak around 2 GeV and measured its flux to 10% accuracy. The position and the absolute flux of the peak agree with the prediction of the Standard Leaky Box model for the "secondary" antiprotons. At low energies below I GeV, we observe an excess antiproton flux over the simple Standard Leaky Box prediction. This might indicate that the propagation mechanism needs to be modified, or might suggest a contribution of low-energy antiproton component from novel sources such as evaporating primordial black holes or the annihilating neutralino dark matter. Data from '98 and future Rights are expected to help us to clarify the situation. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Tokyo, Tokyo 1130033, Japan. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 3050801, Japan. Kobe Univ, Kobe, Hyogo 6578501, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, College Pk, MD 20742 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Kyoto Univ, Kyoto 6068502, Japan. RP Orito, S (reprint author), Univ Tokyo, Tokyo 1130033, Japan. RI MOTOKI, Masakazu/B-4212-2009 NR 19 TC 1 Z9 1 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0273-1177 J9 ADV SPACE RES PY 2001 VL 26 IS 11 BP 1847 EP 1850 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BS67K UT WOS:000170800600022 ER PT B AU Fishman, GJ AF Fishman, GJ BE Livio, M Panagia, N Sahu, K TI Observations of gamma-ray bursts SO SUPERNOVAE AND GAMMA-RAY BURSTS: THE GREATEST EXPLOSIONS SINCE THE BIG BANG SE SPACE TELESCOPE SCIENCE INSTITUTE SYMPOSIUM SERIES LA English DT Proceedings Paper CT Space-Telescope-Science-Institute Symposium on the Greatest Explosions Since the Big Bang CY MAY 03-06, 1999 CL BALTIMORE, MD SP Space Telescope Sci Inst ID BATSE; AFTERGLOW; ENERGY AB Gamma-ray bursts (GRBs) are now recognized as the most luminous known objects in the Universe. Their brief, random appearance in the gamma-ray region had made their study difficult since their discovery, over thirty-five years ago. The recent discoveries of GRB afterglow radiation in other wavelengths and observations of their faint host galaxies have provided the long-sought breakthrough in the direct determination of their distance and luminosity scales. The observed time profiles of GRBs are very diverse and their durations cover a wide range. Their general spectral characteristics are summarized, primarily from data obtained from the BATSE experiment on the Compton Gamma-Ray Observatory. With over 2500 GRBs now observed, these temporal and spectral signatures, as well as population studies and global properties of GRBs., can now be described with greater accuracy than previously possible. C1 NASA, George C Marshall Space Flight Ctr, Dept Space Sci, Huntsville, AL 35812 USA. RP Fishman, GJ (reprint author), NASA, George C Marshall Space Flight Ctr, Dept Space Sci, SD-50, Huntsville, AL 35812 USA. NR 25 TC 2 Z9 2 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE CB2 1RP, CAMBS, ENGLAND BN 0-521-79141-3 J9 SPACE TEL S PY 2001 VL 13 BP 9 EP 16 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT43Z UT WOS:000173024800002 ER PT B AU Harding, AK AF Harding, AK BE Livio, M Panagia, N Sahu, K TI Magnetars, soft gamma-ray repeaters and gamma-ray bursts SO SUPERNOVAE AND GAMMA-RAY BURSTS: THE GREATEST EXPLOSIONS SINCE THE BIG BANG SE SPACE TELESCOPE SCIENCE INSTITUTE SYMPOSIUM SERIES LA English DT Proceedings Paper CT Space-Telescope-Science-Institute Symposium on the Greatest Explosions Since the Big Bang CY MAY 03-06, 1999 CL BALTIMORE, MD SP Space Telescope Sci Inst ID MAGNETIZED NEUTRON-STARS; X-RAY; PULSAR; DISCOVERY; SPECTRUM; SGR-1900+14; SUPERNOVA; FIELDS AB Recent observations of soft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars are providing evidence for the existence of magnetars, a class of neutron stars with surface magnetic fields exceeding the critical field of 4.4 x 10(13) Gauss. Magnetars are the first astrophysical sources believed to derive their primary radiation power from magnetic energy, which substantially exceeds their rotational energy. In addition, the physics of supercritical magnetic fields operates in a more exotic realm than even that of normal pulsars. The discovery of long periods and high period derivatives in soft gamma-ray repeaters (SGRs) over the past year strongly suggests that SGRs are magnetars. But do magnetars have any relation to classical gamma-ray bursts (GRBs)? I will review the evidence that SGRs are magnetars and discuss the question of whether any of the classical GRBs could be magnetars. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Harding, AK (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Harding, Alice/D-3160-2012 NR 41 TC 0 Z9 0 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE CB2 1RP, CAMBS, ENGLAND BN 0-521-79141-3 J9 SPACE TEL S PY 2001 VL 13 BP 121 EP 130 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT43Z UT WOS:000173024800011 ER PT J AU Tsurutani, BT Zhou, XY Vasyliunas, VM Haerendel, G Arballo, JK Lakhina, GS AF Tsurutani, BT Zhou, XY Vasyliunas, VM Haerendel, G Arballo, JK Lakhina, GS TI Interplanetary shocks, magnetopause boundary layers and dayside auroras: The importance of a very small magnetospheric region SO SURVEYS IN GEOPHYSICS LA English DT Review DE aurora; interplanetary shocks; magnetopause ID ELECTROSTATIC SOLITARY WAVES; BAND PLASMA-WAVES; PARTICLE INTERACTIONS; JUPITER; POLAR; BIPOLAR; TURBULENCE; SIMULATION; MISSION; GEOTAIL AB Dayside near-polar auroral brightenings occur when interplanetary shocks impinge upon the Earth's magnetosphere. The aurora first brightens near local noon and then propagates toward dawn and dusk along the auroral oval. The propagation speed of this wave of auroral light is similar to 10 km s(-1) in the ionosphere. This speed is comparable to the solar wind speed along the outer magnetosphere. The fundamental shock-magnetospheric interaction occurs at the magnetopause and its boundary layer. Several physical mechanisms transferring energy from the solar wind directly to the magnetosphere and from the magnetosphere to the ionosphere are reviewed. The same physical processes can occur at other solar system magnetospheres. We use the Haerendel (1994) formulation to estimate the acceleration of energetic electrons to 50 keV in the Jovian magnetosphere/ionosphere. Auroral brightenings by shocks could be used as technique to discover planets in other stellar systems. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Max Planck Inst Aeron, D-3411 Katlenburg Duhm, Germany. Int Univ Bremen, D-28725 Bremen, Germany. Indian Inst Geomagnetism, Bombay 400005, Maharashtra, India. RP Tsurutani, BT (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RI Lakhina, Gurbax /C-9295-2012; OI Lakhina, Gurbax /0000-0002-8956-486X NR 63 TC 24 Z9 25 U1 2 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0169-3298 J9 SURV GEOPHYS JI Surv. Geophys. PY 2001 VL 22 IS 2 BP 101 EP 130 DI 10.1023/A:1012952414384 PG 30 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 496FC UT WOS:000172384700001 ER PT J AU Degnan, JJ AF Degnan, JJ TI Unified approach to photon-counting microlaser rangers, transponders, and altimeters SO SURVEYS IN GEOPHYSICS LA English DT Article; Proceedings Paper CT Symposium on Evolving Geodesy - From Static to Kinematics, on Laser Technology CY APR 25, 2000 CL NICE, FRANCE SP European Geophys Soc DE interplanetary ranging; laser altimetry; laser ranging; laser transponders; lidar; precision orbits; time transfer; topography ID LASER AB Unlike current manned systems, NASA's next generation SLR2000 Satellite Laser Ranging (SLR) station is fully autonomous, eye-safe, relatively compact and inexpensive, and, during daytime tracking, operates at signal-to-noise ratios several orders of magnitude below unity. Tiny, passively Q-switched microlasers generate ultra-short pulses with output energies on the order of 100 muJ at few kHz rates to achieve mm-level ranging precision to satellite altitudes of 20,000 km. Special ranging receivers, combined with Poisson statistical analysis of the received photon distribution, enable the system to rapidly and reliably identify and extract the single photon laser echoes from the solar background. The enhanced rate of return, combined with a uniform signal strength, can actually drive down both systematic and random range errors. The new SLR2000 technology has already spawned exciting new applications. Compact microlaser altimeters, capable of mapping the surface of a planet or other celestial body at multikilohertz rates, is one such application, and a high altitude, airborne version is currently being developed under NASA's Instrument Incubator Program. Interplanetary microlaser transponders would be capable of performing decimeter ranging or subnanosecond time transfer to spacecraft throughout the inner Solar System, resulting in improved knowledge of planetary motions and librations and enhanced General Relativity experiments. C1 NASA, Geosci Technol Off, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Degnan, JJ (reprint author), NASA, Geosci Technol Off, Goddard Space Flight Ctr, Code 920-3, Greenbelt, MD 20771 USA. NR 11 TC 15 Z9 17 U1 2 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0169-3298 J9 SURV GEOPHYS JI Surv. Geophys. PY 2001 VL 22 IS 5-6 BP 431 EP 447 DI 10.1023/A:1015659931843 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 530RJ UT WOS:000174372500002 ER PT J AU Luthcke, SB Carabajal, CC Rowlands, DD Pavlis, DE AF Luthcke, SB Carabajal, CC Rowlands, DD Pavlis, DE TI Improvements in spaceborne laser altimeter data geolocation SO SURVEYS IN GEOPHYSICS LA English DT Article; Proceedings Paper CT Symposium on Evolving Geodesy - From Static to Kinematics, on Laser Technology CY APR 25, 2000 CL NICE, FRANCE SP European Geophys Soc DE altimetry; geolocation; instrument biases; laser altimetry; laser remote sensing; on-orbit calibration techniques; orbit determination ID ORBIT; MARS AB For many science applications of laser altimetry, the precise location of the point on the Earth's surface from which the laser energy reflects is required. The laser surface return geolocation is computed from the laser altimeter's range observation in combination with precise knowledge of spacecraft position, instrument tracking points referenced to the spacecraft center of mass, spacecraft attitude, laser orientation, observation and attitude data time tags. An approach that simultaneously estimates the geometric and dynamic parameters of the orbit and laser range measurement model by a combined reduction of both spacecraft tracking and laser altimeter surface range residuals is applied to produce improved pointing, orbit and range bias solutions and therefore improved geolocation. The data acquired by the Shuttle Laser Altimeter (SLA)-01 and 02 missions constitute a valuable pathfinder data set to test algorithms in preparation for the upcoming VCL (Vegetation Canopy Lidar) and ICESat (Ice, Cloud and Elevation Satellite) missions. Results from a preliminary SLA-01 data analysis are presented along with a brief description of the methodology and its application to future spaceborne missions. C1 NASA, Goddard Space Flight Ctr, Space Geodesy Branch, NVI Inc, Greenbelt, MD 20771 USA. Raytheon ITSS, Geodynam, Greenbelt, MD 20770 USA. RP Luthcke, SB (reprint author), NASA, Goddard Space Flight Ctr, Space Geodesy Branch, NVI Inc, Code 926, Greenbelt, MD 20771 USA. EM sluthcke@geodesy2.gsfc.nasa.gov RI Rowlands, David/D-2751-2012; Luthcke, Scott/D-6283-2012 NR 14 TC 4 Z9 4 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0169-3298 J9 SURV GEOPHYS JI Surv. Geophys. PY 2001 VL 22 IS 5-6 BP 549 EP 559 DI 10.1023/A:1015636721365 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 530RJ UT WOS:000174372500011 ER EF