FN Thomson Reuters Web of Science™ VR 1.0 PT B AU COPPENBARGER, RA CHENG, VHL AF COPPENBARGER, RA CHENG, VHL GP IEEE, CONTROL SYST SOC TI SIMULATION EVALUATION OF A PILOT INTERFACE WITH AN AUTOMATED ROTORCRAFT OBSTACLE AVOIDANCE SYSTEM SO SECOND IEEE CONFERENCE ON CONTROL APPLICATIONS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 2nd IEEE Conference on Control Applications CY SEP 13-16, 1993 CL VANCOUVER, CANADA SP IEEE, CONTROL SYST SOC C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-0908-1 PY 1993 BP 649 EP 657 PG 9 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA BA20D UT WOS:A1993BA20D00103 ER PT B AU ZELENKA, RE YEE, Z ZIRKLER, A AF ZELENKA, RE YEE, Z ZIRKLER, A GP IEEE, CONTROL SYST SOC TI FLIGHT TEST DEVELOPMENT AND EVALUATION OF A KALMAN FILTER STATE ESTIMATOR FOR LOW-ALTITUDE FLIGHT SO SECOND IEEE CONFERENCE ON CONTROL APPLICATIONS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 2nd IEEE Conference on Control Applications CY SEP 13-16, 1993 CL VANCOUVER, CANADA SP IEEE, CONTROL SYST SOC C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-0908-1 PY 1993 BP 783 EP 790 PG 8 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA BA20D UT WOS:A1993BA20D00124 ER PT B AU VARY, A AF VARY, A BE Vary, A TI OVERVIEW OF APPLICATIONS AND POTENTIALS OF ACOUSTO-ULTRASONICS SO SECOND INTERNATIONAL CONFERENCE ON ACOUSTO-ULTRASONICS: ACOUSTO-ULTRASONIC MATERIALS CHARACTERIZATION LA English DT Proceedings Paper CT 2nd International Conference on Acousto-Ultrasonics: Acousto-Ultrasonic Materials Characterization CY JUN 24-25, 1993 CL ATLANTA, GA SP AMER SOC NONDESTRUCT TESTING INC C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NONDESTRUCTIVE TESTING PI COLUMBUS PA 1711 ARLINGATE LANE, PO BOX 28518, COLUMBUS, OH 43228-0518 BN 0-931403-20-0 PY 1993 BP 7 EP 8 PG 2 WC Acoustics; Materials Science, Characterization & Testing SC Acoustics; Materials Science GA BA75R UT WOS:A1993BA75R00002 ER PT B AU KAUTZ, HE AF KAUTZ, HE BE Vary, A TI DETERMINATION OF PLATE WAVE VELOCITIES AND DIFFUSE FIELD DECAY-RATES WITH BROAD-BAND ACOUSTOULTRASONIC SIGNALS SO SECOND INTERNATIONAL CONFERENCE ON ACOUSTO-ULTRASONICS: ACOUSTO-ULTRASONIC MATERIALS CHARACTERIZATION LA English DT Proceedings Paper CT 2nd International Conference on Acousto-Ultrasonics: Acousto-Ultrasonic Materials Characterization CY JUN 24-25, 1993 CL ATLANTA, GA SP AMER SOC NONDESTRUCT TESTING INC C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NONDESTRUCTIVE TESTING PI COLUMBUS PA 1711 ARLINGATE LANE, PO BOX 28518, COLUMBUS, OH 43228-0518 BN 0-931403-20-0 PY 1993 BP 75 EP 83 PG 9 WC Acoustics; Materials Science, Characterization & Testing SC Acoustics; Materials Science GA BA75R UT WOS:A1993BA75R00009 ER PT B AU KAUTZ, HE CHULYA, A AF KAUTZ, HE CHULYA, A BE Vary, A TI ACOUSTOULTRASONIC ANALYSIS OF FAILURE IN CERAMIC-MATRIX SO SECOND INTERNATIONAL CONFERENCE ON ACOUSTO-ULTRASONICS: ACOUSTO-ULTRASONIC MATERIALS CHARACTERIZATION LA English DT Proceedings Paper CT 2nd International Conference on Acousto-Ultrasonics: Acousto-Ultrasonic Materials Characterization CY JUN 24-25, 1993 CL ATLANTA, GA SP AMER SOC NONDESTRUCT TESTING INC C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NONDESTRUCTIVE TESTING PI COLUMBUS PA 1711 ARLINGATE LANE, PO BOX 28518, COLUMBUS, OH 43228-0518 BN 0-931403-20-0 PY 1993 BP 265 EP 272 PG 8 WC Acoustics; Materials Science, Characterization & Testing SC Acoustics; Materials Science GA BA75R UT WOS:A1993BA75R00027 ER PT J AU LAWLESS, BD WILLIAMS, J AF LAWLESS, BD WILLIAMS, J TI CARBONYL IRON PARTICLES IN MAGNETIC CELL SORTING SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article DE CARBONYL IRON; DEXTRAN; MAGNETICS; CELL SEPARATION ID SEPARATION; MICROSPHERES AB Iron-dextran microspheres are easily and inexpensively made by coating uniformly sized carbonyl iron particles with dextran. The iron-dextran spheres can be conjugated with a variety of ligands (antibodies, lectins, avidin, etc.) and used with a permanent rare earth magnet to remove cells, organelles, or macromolecules from mixtures and suspensions. The spheres can be stored indefinitely for use when they are needed. Results obtained with iron-dextran particles in magnetic cell sorting are comparable to those with commercial products. They are particularly helpful when large numbers of cells are to be sorted or when a large panel of antibodies is needed. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RP LAWLESS, BD (reprint author), ROCKEFELLER UNIV,DEPT CELLULAR PHYSIOL & IMMUNOL,BOX 280,1230 YORK AVE,NEW YORK,NY 10021, USA. NR 12 TC 0 Z9 1 U1 1 U2 2 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 SN 0149-6395 J9 SEPAR SCI TECHNOL JI Sep. Sci. Technol. PY 1993 VL 28 IS 11-12 BP 1939 EP 1945 DI 10.1080/01496399308016724 PG 7 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA LM916 UT WOS:A1993LM91600001 ER PT J AU FREUND, RW GUTKNECHT, MH NACHTIGAL, NM AF FREUND, RW GUTKNECHT, MH NACHTIGAL, NM TI AN IMPLEMENTATION OF THE LOOK-AHEAD LANCZOS-ALGORITHM FOR NON-HERMITIAN MATRICES SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE LANCZOS METHOD; ORTHOGONAL POLYNOMIALS; LOOK-AHEAD STEPS; EIGENVALUE PROBLEMS; ITERATIVE METHODS; NON-HERMITIAN MATRICES; SPARSE LINEAR SYSTEMS ID LINEAR-SYSTEMS AB The nonsymmetric Lanczos method can be used to compute eigenvalues of large sparse non-Hermitian matrices or to solve large sparse non-Hermitian linear systems. However, the original Lanczos algorithm is susceptible to possible breakdowns and potential instabilities. An implementation of a look-ahead version of the Lanczos algorithm is presented that, except for the very special situation of an incurable breakdown, overcomes these problems by skipping over those steps in which a breakdown or near-breakdown would occur in the standard process. The proposed algorithm can handle look-ahead steps of any length and requires the same number of matrix-vector products and inner products as the standard Lanczos process without look-ahead. C1 NASA,AMES RES CTR,ADV COMP SCI RES INST,MOFFETT FIELD,CA 94035. SWISS FED INST TECHNOL,INTERDISCIPLINARY PROJECT CTR SUPERCOMP,CH-8092 ZURICH,SWITZERLAND. RI Gutknecht, Martin/C-5250-2012 NR 29 TC 166 Z9 166 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD JAN PY 1993 VL 14 IS 1 BP 137 EP 158 DI 10.1137/0914009 PG 22 WC Mathematics, Applied SC Mathematics GA KP465 UT WOS:A1993KP46500009 ER PT J AU PRATT, TW AF PRATT, TW TI KERNEL-CONTROL PARALLEL VERSUS DATA PARALLEL - A TECHNICAL COMPARISON SO SIGPLAN NOTICES LA English DT Article C1 NASA, GODDARD SPACE FLIGHT CTR, CTR EXCELLENCE SPACE DATA & INFORMAT SCI, GREENBELT, MD 20771 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 2 PENN PLAZA, STE 701, NEW YORK, NY 10121-0701 USA SN 0362-1340 J9 SIGPLAN NOTICES JI Sigplan Not. PD JAN PY 1993 VL 28 IS 1 BP 5 EP 8 PG 4 WC Computer Science, Software Engineering SC Computer Science GA KG090 UT WOS:A1993KG09000002 ER PT J AU PONNUSAMY, R SALTZ, J DAS, R KOELBEL, C CHOUDHARY, A AF PONNUSAMY, R SALTZ, J DAS, R KOELBEL, C CHOUDHARY, A TI EMBEDDING DATA MAPPERS WITH DISTRIBUTED MEMORY MACHINE COMPILERS SO SIGPLAN NOTICES LA English DT Article; Proceedings Paper CT 2ND WORKSHOP ON LANGUAGES, COMPILERS, AND RUN-TIME ENVIRONMENTS FOR DISTRIBUTED MEMORY MULTIPROCESSORS CY SEP 30-OCT 02, 1992 CL BOULDER, CO SP UNIV COLORADO C1 SYRACUSE UNIV,NE PARALLEL ARCHITECTURES CTR,SYRACUSE,NY 13244. NASA,LANGLEY RES CTR,ICASE,HAMPTON,VA 23666. RICE UNIV,CTR RES PARALLEL COMPUTAT,HOUSTON,TX 77251. RI Choudhary, Alok/C-5486-2009 NR 16 TC 4 Z9 4 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 SN 0362-1340 J9 SIGPLAN NOTICES JI Sigplan Not. PD JAN PY 1993 VL 28 IS 1 BP 52 EP 55 PG 4 WC Computer Science, Software Engineering SC Computer Science GA KG090 UT WOS:A1993KG09000014 ER PT J AU CHATTERJEE, S GILBERT, JR SCHREIBER, R TENG, SH AF CHATTERJEE, S GILBERT, JR SCHREIBER, R TENG, SH TI OPTIMAL EVALUATION OF ARRAY EXPRESSIONS ON MASSIVELY PARALLEL MACHINES SO SIGPLAN NOTICES LA English DT Article; Proceedings Paper CT 2ND WORKSHOP ON LANGUAGES, COMPILERS, AND RUN-TIME ENVIRONMENTS FOR DISTRIBUTED MEMORY MULTIPROCESSORS CY SEP 30-OCT 02, 1992 CL BOULDER, CO SP UNIV COLORADO AB We investigate the problem of optimal evaluation of Fortran-90 style array expressions on a massively parallel distributed-memory machine. On such machines, an elementwise operation can be performed in unit time for arrays whose corresponding elements are in the same processor. If the arrays are not aligned in this manner, the cost of alignment is part of the cost of expression evaluation. The choice of where to perform the operation then affects this cost. We demonstrate how a dynamic programming technique can be applied to solve this problem efficiently for a wide variety of interconnection schemes, including multidimensional grids and rings, hypercubes, and fat-trees. We also consider the variant where the operations may change the shape of the arrays, and show that our approach extends naturally to handle this case. C1 NASA,AMES RES CTR,ADV COMP SCI RES INST,MOFFETT FIELD,CA 94035. XEROX CORP,PALO ALTO RES CTR,PALO ALTO,CA 94304. NR 4 TC 2 Z9 2 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 SN 0362-1340 J9 SIGPLAN NOTICES JI Sigplan Not. PD JAN PY 1993 VL 28 IS 1 BP 68 EP 71 PG 4 WC Computer Science, Software Engineering SC Computer Science GA KG090 UT WOS:A1993KG09000018 ER PT J AU CHAPMAN, B MEHROTRA, P ZIMA, H AF CHAPMAN, B MEHROTRA, P ZIMA, H TI USER DEFINED MAPPINGS IN VIENNA FORTRAN SO SIGPLAN NOTICES LA English DT Article C1 UNIV VIENNA, DEPT STAT & COMP SCI, A-1210 VIENNA, AUSTRIA. NASA, LANGLEY RES CTR, ICASE, HAMPTON, VA 23681 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 2 PENN PLAZA, STE 701, NEW YORK, NY 10121-0701 USA SN 0362-1340 J9 SIGPLAN NOTICES JI Sigplan Not. PD JAN PY 1993 VL 28 IS 1 BP 72 EP 75 PG 4 WC Computer Science, Software Engineering SC Computer Science GA KG090 UT WOS:A1993KG09000019 ER PT J AU ROSING, M SCHNABEL, RB WEAVER, RP AF ROSING, M SCHNABEL, RB WEAVER, RP TI A PROGRAMMABLE PREPROCESSOR APPROACH TO EFFICIENT PARALLEL LANGUAGE DESIGN SO SIGPLAN NOTICES LA English DT Article AB This paper briefly describes the design and philosophy of the new stage of our parallel language research, which we are just now beginning. The basic goals for this new language are to support a very broad range of parallel computations, to provide ways to obtain efficient code over this entire range, and to provide ease of programming as far as this is consistent with the first two goals. To achieve these goals, we are designing an explicitly parallel language that allows the expression of fundamental parallel constructs, including synchronization, communication, and data distribution, at either low- or high-levels, with a well-structured progression between levels. The multi-level approach to parallel language constructs should allow the language to meet the needs of a broad variety of sophisticated and unsophisticated users, as well as providing expressiveness and efficiency for a broad range of applications. This approach will also allow us to develop a fully expressive prototype of our language quickly. C1 NASA, LANGLEY RES CTR, INST COMP APPLICAT SCI & ENGN, HAMPTON, VA 23665 USA. UNIV COLORADO, DEPT COMP SCI, BOULDER, CO 80309 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 2 PENN PLAZA, STE 701, NEW YORK, NY 10121-0701 USA SN 0362-1340 J9 SIGPLAN NOTICES JI Sigplan Not. PD JAN PY 1993 VL 28 IS 1 BP 76 EP 79 PG 4 WC Computer Science, Software Engineering SC Computer Science GA KG090 UT WOS:A1993KG09000020 ER PT B AU MELSON, ND SANETRIK, MD ATKINS, HL AF MELSON, ND SANETRIK, MD ATKINS, HL BE Melson, ND Manteuffel, TA McCormick, SF TI TIME ACCURATE NAVIER-STOKES CALCULATIONS WITH MULTIGRID ACCELERATION SO SIXTH COPPER MOUNTAIN CONFERENCE ON MULTIGRID METHODS SE NASA CONFERENCE PUBLICATION LA English DT Proceedings Paper CT 6th Copper Mountain Conference on Multigrid Methods CY APR 04-09, 1993 CL COPPER MT, CO SP NASA, USAF, OFF SCI RES, BOLLING AIR FORCE BASE, US DOE, NATL SCI FDN C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23681. NR 0 TC 21 Z9 21 U1 0 U2 1 PU NASA PI WASHINGTON PA WASHINGTON, DC 20546 J9 NASA CONF P PY 1993 VL 3224 BP 423 EP 437 PN 1-2 PG 15 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BB85A UT WOS:A1993BB85A00029 ER PT B AU MORANO, E DERVIEUX, A AF MORANO, E DERVIEUX, A BE Melson, ND Manteuffel, TA McCormick, SF TI LOOKING FOR O(N) NAVIER-STOKES SOLUTIONS ON NON-STRUCTURED MESHES SO SIXTH COPPER MOUNTAIN CONFERENCE ON MULTIGRID METHODS SE NASA CONFERENCE PUBLICATION LA English DT Proceedings Paper CT 6th Copper Mountain Conference on Multigrid Methods CY APR 04-09, 1993 CL COPPER MT, CO SP NASA, USAF, OFF SCI RES, BOLLING AIR FORCE BASE, US DOE, NATL SCI FDN C1 NASA,LANGLEY RES CTR,ICASE,HAMPTON,VA 23665. NR 0 TC 5 Z9 5 U1 0 U2 3 PU NASA PI WASHINGTON PA WASHINGTON, DC 20546 J9 NASA CONF P PY 1993 VL 3224 BP 449 EP 463 PN 1-2 PG 15 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BB85A UT WOS:A1993BB85A00031 ER PT B AU BATES, JR MCCORMICK, SF RUGE, J SHOLL, DS YAVNEH, I AF BATES, JR MCCORMICK, SF RUGE, J SHOLL, DS YAVNEH, I BE Melson, ND Manteuffel, TA McCormick, SF TI A SEMI-LAGRANGIAN APPROACH TO THE SHALLOW WATER EQUATIONS SO SIXTH COPPER MOUNTAIN CONFERENCE ON MULTIGRID METHODS SE NASA CONFERENCE PUBLICATION LA English DT Proceedings Paper CT 6th Copper Mountain Conference on Multigrid Methods CY APR 04-09, 1993 CL COPPER MT, CO SP NASA, USAF, OFF SCI RES, BOLLING AIR FORCE BASE, US DOE, NATL SCI FDN C1 NASA,GODDARD SPACE FLIGHT CTR,GODDARD LAB ATMOSPHERES,GREENBELT,MD 20771. NR 0 TC 1 Z9 1 U1 0 U2 0 PU NASA PI WASHINGTON PA WASHINGTON, DC 20546 J9 NASA CONF P PY 1993 VL 3224 BP 593 EP 604 PN 1-2 PG 12 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BB85A UT WOS:A1993BB85A00040 ER PT J AU SOCKOL, PM AF SOCKOL, PM BE Melson, ND Manteuffel, TA McCormick, SF TI MULTIGRID SOLUTION OF THE NAVIER-STOKES EQUATIONS ON HIGHLY STRETCHED GRIDS WITH DEFECT CORRECTION SO SIXTH COPPER MOUNTAIN CONFERENCE ON MULTIGRID METHODS SE NASA CONFERENCE PUBLICATION LA English DT Proceedings Paper CT 6th Copper Mountain Conference on Multigrid Methods CY APR 04-09, 1993 CL COPPER MT, CO SP NASA, USAF, OFF SCI RES, BOLLING AIR FORCE BASE, US DOE, NATL SCI FDN C1 NASA,LEWIS RES CTR,DIV INTERNAL FLUID MECH,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NASA PI WASHINGTON PA WASHINGTON, DC 20546 J9 NASA CONF P PY 1993 VL 3224 BP 605 EP 619 PN 1-2 PG 15 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BB85A UT WOS:A1993BB85A00041 ER PT B AU OVERMAN, A VANROSENDALE, J AF OVERMAN, A VANROSENDALE, J BE Melson, ND Manteuffel, TA McCormick, SF TI MAPPING ROBUST PARALLEL MULTIGRID ALGORITHMS TO SCALABLE MEMORY ARCHITECTURES SO SIXTH COPPER MOUNTAIN CONFERENCE ON MULTIGRID METHODS SE NASA CONFERENCE PUBLICATION LA English DT Proceedings Paper CT 6th Copper Mountain Conference on Multigrid Methods CY APR 04-09, 1993 CL COPPER MT, CO SP NASA, USAF, OFF SCI RES, BOLLING AIR FORCE BASE, US DOE, NATL SCI FDN C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23681. NR 0 TC 2 Z9 2 U1 0 U2 0 PU NASA PI WASHINGTON PA WASHINGTON, DC 20546 J9 NASA CONF P PY 1993 VL 3224 BP 635 EP 647 PN 1-2 PG 13 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BB85A UT WOS:A1993BB85A00043 ER PT J AU VENKATAKRISHNAN, V MAVRIPLIS, DJ BERGER, MJ AF VENKATAKRISHNAN, V MAVRIPLIS, DJ BERGER, MJ BE Melson, ND Manteuffel, TA McCormick, SF TI UNSTRUCTURED MULTIGRID THROUGH AGGLOMERATION SO SIXTH COPPER MOUNTAIN CONFERENCE ON MULTIGRID METHODS SE NASA CONFERENCE PUBLICATION LA English DT Proceedings Paper CT 6th Copper Mountain Conference on Multigrid Methods CY APR 04-09, 1993 CL COPPER MT, CO SP NASA, USAF, OFF SCI RES, BOLLING AIR FORCE BASE, US DOE, NATL SCI FDN C1 NASA,AMES RES CTR,COMP SCI CORP,NAS APPL RES BRANCH,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NASA PI WASHINGTON PA WASHINGTON, DC 20546 J9 NASA CONF P PY 1993 VL 3224 BP 649 EP 662 PN 1-2 PG 14 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BB85A UT WOS:A1993BB85A00044 ER PT J AU WARREN, GP ROBERTS, TW AF WARREN, GP ROBERTS, TW BE Melson, ND Manteuffel, TA McCormick, SF TI MULTIGRID PROPERTIES OF UPWIND-BIASED DATA RECONSTRUCTIONS SO SIXTH COPPER MOUNTAIN CONFERENCE ON MULTIGRID METHODS SE NASA CONFERENCE PUBLICATION LA English DT Proceedings Paper CT 6th Copper Mountain Conference on Multigrid Methods CY APR 04-09, 1993 CL COPPER MT, CO SP NASA, USAF, OFF SCI RES, BOLLING AIR FORCE BASE, US DOE, NATL SCI FDN C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23665. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NASA PI WASHINGTON PA WASHINGTON, DC 20546 J9 NASA CONF P PY 1993 VL 3224 BP 663 EP 677 PN 1-2 PG 15 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BB85A UT WOS:A1993BB85A00045 ER PT B AU BEICHMAN, C AF BEICHMAN, C BE Soifer, BT TI THE IRAS VIEW OF THE GALAXY SO SKY SURVEYS: PROTOSTARS TO PROTOGALAXIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Sky Surveys: Protostars to Protogalaxies, in Honor of Gerry Neugebauer CY SEP 16-18, 1992 CL CALIF INST TECHNOL, PASADENA, CA SP CALIF INST TECHNOL HO CALIF INST TECHNOL C1 JET PROP LAB,CTR INFRARED PROC & ANAL,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-62-7 J9 ASTR SOC P PY 1993 VL 43 BP 23 EP 34 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94S UT WOS:A1993BZ94S00005 ER PT B AU MADORE, BF AF MADORE, BF BE Soifer, BT TI THE MEGAGALAXY PROJECT - BOLOMETRIC HUBBLE TYPES FOR GALAXIES SO SKY SURVEYS: PROTOSTARS TO PROTOGALAXIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Sky Surveys: Protostars to Protogalaxies, in Honor of Gerry Neugebauer CY SEP 16-18, 1992 CL CALIF INST TECHNOL, PASADENA, CA SP CALIF INST TECHNOL HO CALIF INST TECHNOL C1 CALTECH,PALOMAR OBSERV,NASA,IPAC EXTRAGALACT DATABASE,PASADENA,CA 91125. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-62-7 J9 ASTR SOC P PY 1993 VL 43 BP 149 EP 152 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94S UT WOS:A1993BZ94S00023 ER PT B AU HAUSER, MG AF HAUSER, MG BE Soifer, BT TI COSMOLOGY FROM COBE SO SKY SURVEYS: PROTOSTARS TO PROTOGALAXIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Sky Surveys: Protostars to Protogalaxies, in Honor of Gerry Neugebauer CY SEP 16-18, 1992 CL CALIF INST TECHNOL, PASADENA, CA SP CALIF INST TECHNOL HO CALIF INST TECHNOL C1 NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-62-7 J9 ASTR SOC P PY 1993 VL 43 BP 205 EP 216 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94S UT WOS:A1993BZ94S00030 ER PT B AU ROELLIG, TL AF ROELLIG, TL BE Soifer, BT TI SURVEYS FROM THE INFRARED TELESCOPE IN-SPACE SO SKY SURVEYS: PROTOSTARS TO PROTOGALAXIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Sky Surveys: Protostars to Protogalaxies, in Honor of Gerry Neugebauer CY SEP 16-18, 1992 CL CALIF INST TECHNOL, PASADENA, CA SP CALIF INST TECHNOL HO CALIF INST TECHNOL C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-62-7 J9 ASTR SOC P PY 1993 VL 43 BP 227 EP 232 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94S UT WOS:A1993BZ94S00033 ER PT B AU WERNER, MW AF WERNER, MW BE Soifer, BT TI SIRTF SURVEYS SO SKY SURVEYS: PROTOSTARS TO PROTOGALAXIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Sky Surveys: Protostars to Protogalaxies, in Honor of Gerry Neugebauer CY SEP 16-18, 1992 CL CALIF INST TECHNOL, PASADENA, CA SP CALIF INST TECHNOL HO CALIF INST TECHNOL C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 3 Z9 3 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-62-7 J9 ASTR SOC P PY 1993 VL 43 BP 249 EP 266 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94S UT WOS:A1993BZ94S00035 ER PT J AU HUTCHINSON, GL GUENZI, WD LIVINGSTON, GP AF HUTCHINSON, GL GUENZI, WD LIVINGSTON, GP TI SOIL-WATER CONTROLS ON AEROBIC SOIL EMISSION OF GASEOUS NITROGEN-OXIDES SO SOIL BIOLOGY & BIOCHEMISTRY LA English DT Article ID NITRIC-OXIDE; MICROBIAL-PRODUCTION; NITRATE; N2O; NITRIFICATION; NITRIFIERS; GRASSLAND; SYSTEM; NO AB Soil water content has multiple effects on the emission of gaseous N oxides. To separate and characterize these effects, we monitored rates of CO2, NO, and N2O evolution and changes in inorganic N concentrations of soil under a factorial combination of three N treatments and three water treatments during a 10-day laboratory incubation study. Because the emission of NO from control and NH4NO3-amended soil varied with the rate of chemoautotrophic NH4+ oxidation and was virtually eliminated by a specific inhibitor of that process [nitrapyrin (2-chloro-6-(trichloromethyl)-pyridine)], we concluded that nitrification was the principal NO source over the entire tested range of soil water potentials ( - 10 to less than - 1000 kPa). Denitrification made no significant contribution to N oxide emissions from even the wettest soil, so nitrifiers were probably also responsible for the much smaller emission of N2O under all treatments. Slower ps diffusion in soil with highest, compared to lowest, water content caused a 3-fold reduction in the mean NO:NO3- product ratio of nitrification, suggesting that the NO produced by NH4+-oxidizers is further oxidized unless conditions permit its rapid escape to the atmosphere. Nitrapyrin also eliminated the brief burst of N oxide emissions that typically follows wetting of dry soil, indicating that chemoautotrophic NH4+ oxidation is also involved in this phenomenon despite the poor correlation of the burst's magnitude With soil NH4+ or NO2- concentrations. A second burst of N oxide emissions from control or NH4NO3-amended soil with no inhibitor occurred only where desiccation reduced both NO and CO2 evolution to near zero prior to rewetting the soil after a 7-day drying cycle. C1 NASA,AMES RES CTR,TGS TECHNOL INC,DIV EARTH SYST SCI,MOFFETT FIELD,CA 94035. RP HUTCHINSON, GL (reprint author), USDA ARS,POB E,FT COLLINS,CO 80522, USA. NR 26 TC 66 Z9 67 U1 3 U2 22 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-0717 J9 SOIL BIOL BIOCHEM JI Soil Biol. Biochem. PD JAN PY 1993 VL 25 IS 1 BP 1 EP 9 DI 10.1016/0038-0717(93)90234-3 PG 9 WC Soil Science SC Agriculture GA KH853 UT WOS:A1993KH85300001 ER PT S AU GUHATHAKURTA, M FISHER, RR ALTROCK, RC AF GUHATHAKURTA, M FISHER, RR ALTROCK, RC BE Gabriel, AH TI THE SOLAR-CYCLE VARIATION OF CORONAL TEMPERATURE AND DENSITY DURING CYCLE-21-22 SO SOLAR CORONA SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E1 of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT UNION GEODESY & GEOPHYS, INT ASSOC GEOMAGNETISM & AERON AB In this paper we characterize the temperature and the density structure of the corona utilizing co-spatial spectrophotometric observations during the descending phase of cycle 21 through the ascending phase of cycle 22. The data include ground-based intensity observations of the green (5303 Angstrom Fe XIV) and red (6374 Angstrom Fe X) coronal forbidden Lines from Sacramento Peak and synoptic maps of white-light K-coronal polarized brightness, pB from the High Altitude Observatory, and photospheric magnetographs from the National Solar Observatory, Sacramento Peak. A determination of plasma temperature T can be derived unambiguously from the intensity ratio Fe X/Fe XIV, since both emission lines come from ionized states of Fe, and the ratios are only weakly dependent on density. The latitudinal variation of the temperature and the density within the descending and the ascending phases of solar cycle 21 and 22 are presented. There is a large-scale organization of the inferred coronal temperature distribution; these structures tend to persist through most of the magnetic activity cycle. This distribution differs in spatial and temporal characterization from the traditional picture of sunspot and active region evolution over the range of sunspot cycle. C1 NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. NATL SOLAR OBSERV,GEOPHYS DIRECTORATE,PHILLIPS LAB,ASFC,SUNSPOT,NM 88349. RP GUHATHAKURTA, M (reprint author), UNIV COLORADO,ATMOSPHER & SPACE PHYS LAB,CAMPUS BOX 392,BOULDER,CO 80309, USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042478-3 J9 ADV SPACE RES PY 1993 VL 14 IS 4 BP 49 EP 52 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BA32J UT WOS:A1993BA32J00008 ER PT S AU NEUPERT, WM BROSIUS, JW THOMAS, RJ THOMPSON, WT AF NEUPERT, WM BROSIUS, JW THOMAS, RJ THOMPSON, WT BE Gabriel, AH TI EVIDENCE OF MASS OUTFLOW IN THE LOW CORONA OVER A LARGE SUNSPOT SO SOLAR CORONA SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E1 of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT UNION GEODESY & GEOPHYS, INT ASSOC GEOMAGNETISM & AERON ID TRANSITION ZONE; SOLAR CORONA; SPECTROGRAPH AB An extreme ultraviolet (EW) imaging spectrograph designed for sounding rocket flight has been used to search for velocity fields in the low solar corona. During a flight in May, 1989, we obtained emission line profile measurements along a chord through an active region on the Sun. Relative Doppler velocities were measured in emission lines of Mg IX, Fe XV, and Fe XVI with a sensitivity of 2-3 km s(-1) at 350 A. The only Doppler shift appreciably greater than this level was observed in the line of Mg IX at 368.1 A over the umbra of the large sunspot. The maximum shift measured at that location corresponded to a velocity toward the observer of 14 +/- 3 km s(-1) relative to the mean of measurements in that emission line made elsewhere over the active region. The magnetic field in the low corona was aligned to within 10 degrees of the line of sight at the location of maximum Doppler shift. Depending on the magnetic field geometry, this mass outflow could either re-appear as a downflow of material in distant footpoints of closed coronal loops or, if along open field lines, could contribute to the solar wind. The site of the sunspot was near a major photospheric magnetic field boundary. Such boundaries have been associated with low-speed solar winds as observed in interplanetary plasmas. C1 HUGHES STX CORP,LANHAM,MD 20706. APPL RES CORP,LANDOVER,MD 20785. RP NEUPERT, WM (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 680,GREENBELT,MD 20771, USA. RI Thompson, William/D-7376-2012 NR 14 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042478-3 J9 ADV SPACE RES PY 1993 VL 14 IS 4 BP 61 EP 64 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BA32J UT WOS:A1993BA32J00011 ER PT S AU FOSSI, BCM LANDINI, M THOMAS, RJ NEUPERT, WM AF FOSSI, BCM LANDINI, M THOMAS, RJ NEUPERT, WM BE Gabriel, AH TI ABUNDANCE DETERMINATION IN SOLAR ACTIVE-REGION SO SOLAR CORONA SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E1 of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT UNION GEODESY & GEOPHYS, INT ASSOC GEOMAGNETISM & AERON ID SPECTRUM AB An improved method has been developed to evaluate element abundances from emission line intensities of thin plasmas, depending on the differential emission measure (DEM) of the source. Observations made by the SERTS Rocket EUV Spectrograph are used to perform a detailed analysis of the DEM distribution for temperatures larger than 10(5) K in a solar active region. Comparison of the DEM distributions obtained by means of lines from different elements allows the verification of relative abundances for the most common elements of the solar corona, and gives an abundance estimates for the minor components, such as Na, Al, Ar, Cr, Mn and Zn. C1 UNIV FLORENCE,DEPT ASTRON & SPACE SCI,I-50125 FLORENCE,ITALY. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP FOSSI, BCM (reprint author), OSSERV ASTROFIS ARCETRI,LARGO E FERMI 5,I-50125 FLORENCE,ITALY. NR 13 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042478-3 J9 ADV SPACE RES PY 1993 VL 14 IS 4 BP 163 EP 166 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BA32J UT WOS:A1993BA32J00025 ER PT S AU REAMES, DV AF REAMES, DV BE Gabriel, AH TI CORONAL ELEMENT ABUNDANCES DERIVED FROM SOLAR ENERGETIC PARTICLES SO SOLAR CORONA SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E1 of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT UNION GEODESY & GEOPHYS, INT ASSOC GEOMAGNETISM & AERON AB The large gradual solar-energetic-particle (SEP) events, where abundances are commonly measured, are produced when coronal mass ejections (CMEs) drive shock waves through the corona and the interplanetary medium. The shock accelerates particles from the highly-ionized, similar to 1.5 MK, plasma in a manner that depends only weakly upon the Q/A of the ion, except at very high energies. Averaging the similar to 1 MeV/amu abundances over many events compensates for the acceleration effects to produce abundances that appear to correspond directly to those in the coronal source for all observed elements, including H. The resulting abundances reflect the 4 x enhancement of ions with low values of first ionization potential (FIP) arising from ion-neutral fractionation that occurs as the atoms are transported up from the photosphere. A different pattern of fractionation is found for ions that are shock-accelerated from the high-speed solar wind emerging from coronal holes. RP REAMES, DV (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 661,GREENBELT,MD 20771, USA. NR 12 TC 7 Z9 7 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042478-3 J9 ADV SPACE RES PY 1993 VL 14 IS 4 BP 177 EP 180 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BA32J UT WOS:A1993BA32J00029 ER PT J AU APPELBAUM, J LANDIS, GA SHERMAN, I AF APPELBAUM, J LANDIS, GA SHERMAN, I TI SOLAR-RADIATION ON MARS - UPDATE 1991 SO SOLAR ENERGY LA English DT Article ID MARTIAN ATMOSPHERE AB Detailed information on solar radiation characteristics on Mars are necessary for effective design of future planned solar energy systems operating on the surface of Mars. In this paper we present a procedure and solar radiation related data from which the daily variation of the global, direct beam, and diffuse insolation on Mars are calculated. Given the optical depth of the Mars atmosphere, the global radiation is calculated from the normalized net flux function based on multiple wavelength and multiple scattering of the solar radiation. The direct beam was derived from the optical depth using Beer's law, and the diffuse component was obtained from the difference of the global and the direct beam radiation. The optical depths of the Mars atmosphere were derived from images taken of the Sun with a special diode on the cameras used on the two Viking Landers. C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. SVERDRUP TECHNOL INC,LEWIS RES CTR GRP,BROOK PK,OH 44142. RP APPELBAUM, J (reprint author), TEL AVIV UNIV,FAC ENGN,IL-69978 TEL AVIV,ISRAEL. NR 13 TC 17 Z9 17 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-092X J9 SOL ENERGY JI Sol. Energy PD JAN PY 1993 VL 50 IS 1 BP 35 EP 51 DI 10.1016/0038-092X(93)90006-A PG 17 WC Energy & Fuels SC Energy & Fuels GA KC091 UT WOS:A1993KC09100005 ER PT B AU DUNCAN, BS LUMLEY, JL SHIH, TH TO, WM AF DUNCAN, BS LUMLEY, JL SHIH, TH TO, WM BE Qiu, SQ TI A NEW MODEL FOR THE TURBULENT DISSIPATION SO SOME NEW TRENDS ON FLUID MECHANICS AND THEORETICAL PHYSICS LA English DT Proceedings Paper CT International Conference on Fluid Mechanics and Theoretical Physics, in Honor of Professor Pei-Yuan Chous 90th Anniversary CY JUN 01-03, 1992 CL BEIJING, PEOPLES R CHINA SP Peking Univ, Chinese Soc Theoret & Appl Mech, Chinese Phys Soc C1 NASA,LEWIS RES CTR,SVERDRUP TECHNOL INC,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PEKING UNIV PRESS PI BEIJING PA HAIDIANQU, BEIJING, PEOPLES R CHINA BN 7-301-02070-8 PY 1993 BP 66 EP 81 PG 16 WC Mechanics; Physics, Mathematical SC Mechanics; Physics GA BD18F UT WOS:A1993BD18F00008 ER PT B AU JIANG, BN AF JIANG, BN BE Qiu, SQ TI A UNIFIED METHOD IN COMPUTATIONAL FLUID DYNAMICS SO SOME NEW TRENDS ON FLUID MECHANICS AND THEORETICAL PHYSICS LA English DT Proceedings Paper CT International Conference on Fluid Mechanics and Theoretical Physics, in Honor of Professor Pei-Yuan Chous 90th Anniversary CY JUN 01-03, 1992 CL BEIJING, PEOPLES R CHINA SP Peking Univ, Chinese Soc Theoret & Appl Mech, Chinese Phys Soc C1 NASA,LEWIS RES CTR,INST COMPUTAT MECH PROPULS,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 1 PU PEKING UNIV PRESS PI BEIJING PA HAIDIANQU, BEIJING, PEOPLES R CHINA BN 7-301-02070-8 PY 1993 BP 266 EP 272 PG 7 WC Mechanics; Physics, Mathematical SC Mechanics; Physics GA BD18F UT WOS:A1993BD18F00032 ER PT B AU SHIH, TH AF SHIH, TH BE Qiu, SQ TI 2ND ORDER MODELING OF NEAR-WALL TURBULENCE SO SOME NEW TRENDS ON FLUID MECHANICS AND THEORETICAL PHYSICS LA English DT Proceedings Paper CT International Conference on Fluid Mechanics and Theoretical Physics, in Honor of Professor Pei-Yuan Chous 90th Anniversary CY JUN 01-03, 1992 CL BEIJING, PEOPLES R CHINA SP Peking Univ, Chinese Soc Theoret & Appl Mech, Chinese Phys Soc C1 NASA,LEWIS RES CTR,ICOMP,CTR MODELING TURBULENCE & TRANSIT,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PEKING UNIV PRESS PI BEIJING PA HAIDIANQU, BEIJING, PEOPLES R CHINA BN 7-301-02070-8 PY 1993 BP 403 EP 415 PG 13 WC Mechanics; Physics, Mathematical SC Mechanics; Physics GA BD18F UT WOS:A1993BD18F00069 ER PT B AU YANG, Z SHIH, TH AF YANG, Z SHIH, TH BE Qiu, SQ TI A kappa-epsilon MODELING OF TRANSITIONAL BOUNDARY LAYERS SO SOME NEW TRENDS ON FLUID MECHANICS AND THEORETICAL PHYSICS LA English DT Proceedings Paper CT International Conference on Fluid Mechanics and Theoretical Physics, in Honor of Professor Pei-Yuan Chous 90th Anniversary CY JUN 01-03, 1992 CL BEIJING, PEOPLES R CHINA SP Peking Univ, Chinese Soc Theoret & Appl Mech, Chinese Phys Soc C1 NASA,LEWIS RES CTR,ICOMP,CTR MODELING TURBULENCE & TRANSIT,CLEVELAND,OH 44142. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PEKING UNIV PRESS PI BEIJING PA HAIDIANQU, BEIJING, PEOPLES R CHINA BN 7-301-02070-8 PY 1993 BP 419 EP 420 PG 2 WC Mechanics; Physics, Mathematical SC Mechanics; Physics GA BD18F UT WOS:A1993BD18F00071 ER PT B AU MAYMON, PW DITTMAN, MG PASQUALE, BA JENNINGS, DE MEHALICK, KI TROUT, CJ AF MAYMON, PW DITTMAN, MG PASQUALE, BA JENNINGS, DE MEHALICK, KI TROUT, CJ BE Bely, PY Breckinridge, JB TI OPTICAL DESIGN OF THE COMPOSITE INFRARED SPECTROMETER (CIRS) FOR THE CASSINI MISSION SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RI Jennings, Donald/D-7978-2012 NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 100 EP 111 DI 10.1117/12.158752 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00013 ER PT B AU SHAKLAN, S YU, J BRIGGS, HC AF SHAKLAN, S YU, J BRIGGS, HC BE Bely, PY Breckinridge, JB TI INTEGRATED STRUCTURAL AND OPTICAL MODELING OF THE ORBITING STELLAR INTERFEROMETER SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 124 EP 132 DI 10.1117/12.158754 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00015 ER PT B AU NEEDELS, L LEVINE, BM MILMAN, M AF NEEDELS, L LEVINE, BM MILMAN, M BE Bely, PY Breckinridge, JB TI LIMITS ON ADAPTIVE OPTICS SYSTEMS FOR LIGHTWEIGHT SPACE TELESCOPES SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 176 EP 184 DI 10.1117/12.158760 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00020 ER PT B AU BOLTON, J AF BOLTON, J BE Bely, PY Breckinridge, JB TI CONCEPTUAL DESIGN FOR A 2ND-GENERATION SPACE TELESCOPE SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 NASA,GODDARD SPACE FLIGHT CTR,SYST ENGN OFF,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 197 EP 205 DI 10.1117/12.158794 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00022 ER PT B AU SAHA, TT LEVITON, DB AF SAHA, TT LEVITON, DB BE Bely, PY Breckinridge, JB TI THEORETICAL AND MEASURED ENCIRCLED ENERGY AND WIDE-ANGLE SCATTER OF SUMER DEMONSTRATION TELESCOPE MIRROR IN FUV SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NR 0 TC 7 Z9 7 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 398 EP 409 DI 10.1117/12.158784 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00043 ER PT B AU MILLER, LM AGRONIN, ML BARTMAN, RK KAISER, WJ KENNY, TW NORTON, RL VOTE, EC AF MILLER, LM AGRONIN, ML BARTMAN, RK KAISER, WJ KENNY, TW NORTON, RL VOTE, EC BE Bely, PY Breckinridge, JB TI FABRICATION AND CHARACTERIZATION OF A MICROMACHINED DEFORMABLE MIRROR FOR ADAPTIVE OPTICS APPLICATIONS SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 27 Z9 28 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 421 EP 430 DI 10.1117/12.158786 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00045 ER PT B AU HANNAN, PG WILSON, ME AF HANNAN, PG WILSON, ME BE Bely, PY Breckinridge, JB TI OPTICAL DESIGN OF 2-MIRROR WIDE-FIELD CAMERAS FOR LARGE TELESCOPES SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NR 0 TC 1 Z9 2 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 443 EP 452 DI 10.1117/12.158790 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00048 ER PT B AU JALOTA, L GOTTHELF, EV ZOONERMATKERMANI, S AF JALOTA, L GOTTHELF, EV ZOONERMATKERMANI, S BE Bely, PY Breckinridge, JB TI IMAGE-RECONSTRUCTION AND DECONVOLUTION TECHNIQUES APPLIED TO ASCA DATA SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 NASA,GODDARD SPACE FLIGHT CTR,UNIV SPACE RES ASSOC,GREENBELT,MD 20771. NR 0 TC 11 Z9 11 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 453 EP 464 DI 10.1117/12.158791 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00049 ER PT B AU SHAKLAN, S PRAVDO, S AF SHAKLAN, S PRAVDO, S BE Bely, PY Breckinridge, JB TI A SPACE-BASED CCD EXPERIMENT FOR HIGH-PRECISION ASTROMETRY SO SPACE ASTRONOMICAL TELESCOPES AND INSTRUMENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Space Astronomical Telescopes and Instruments II CY APR 13-14, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1181-7 J9 P SOC PHOTO-OPT INS PY 1993 VL 1945 BP 505 EP 511 DI 10.1117/12.158799 PG 7 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BZ81R UT WOS:A1993BZ81R00055 ER PT S AU KIMBLE, RA DAVIDSEN, AF AF KIMBLE, RA DAVIDSEN, AF BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI OBSERVATIONS OF STARS WITH THE HOPKINS ULTRAVIOLET TELESCOPE SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT ID LOCAL INTERSTELLAR-MEDIUM; PLANETARY-NEBULAE; MODEL ATMOSPHERES; U-GEMINORUM; HYDROGEN; SPECTROSCOPY; IONIZATION; SPECTRA; GRW AB The Hopkins Ultraviolet Telescope (HUT) was flown aboard the space shuttle Columbia as part of the Astro-1 mission during December 1990. During the nine-day flight, HUT carried out 3 Angstrom resolution spectrophotometry of a wide variety of astronomical objects, including a number of stellar targets, in the 912-1860 Angstrom range of the far ultraviolet. A few nearby stars were observed in the 415-912 Angstrom range of the extreme ultraviolet as well. For nearly all of these targets, the spectra obtained by HUT are the first ever obtained in the spectroscopically rich region between Lyman alpha (1216 Angstrom) and the Lyman limit (912 Angstrom). Here, we present highlights of the results obtained by HUT in a variety of areas of stellar astronomy. C1 JOHNS HOPKINS UNIV,CTR ASTROPHYS SCI,BALTIMORE,MD 21218. RP KIMBLE, RA (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771, USA. RI Kimble, Randy/D-5317-2012 NR 35 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 33 EP 42 DI 10.1016/0273-1177(93)90095-S PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00005 ER PT S AU PETRE, R SERLEMITSOS, P MARSHALL, F JAHODA, K SZYMKOWIAK, A SMALE, A SWANK, J CORCORAN, M PTAK, A BOLDT, E HOLT, S KELLEY, R MUSHOTZKY, R WEAVER, K AF PETRE, R SERLEMITSOS, P MARSHALL, F JAHODA, K SZYMKOWIAK, A SMALE, A SWANK, J CORCORAN, M PTAK, A BOLDT, E HOLT, S KELLEY, R MUSHOTZKY, R WEAVER, K BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI BBXRT OBSERVATIONS OF SUPERNOVA-REMNANTS SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT ID X-RAY-EMISSION; NOVA REMNANTS; G109.1-1.0; COMPLEX; PULSAR AB The Broad Band X-Ray Telescope (BBXRT) was designed to perform sensitive, moderate resolution spectroscopy of cosmic X-ray sources in the 0.3-10 keV band from the Space Shuttle. During its nine-day flight in December, 1990, the BBXRT observed a variety of supernova remnants and related objects. We present results from some of these observations, emphasizing the ability of the BBXRT to perform spatially-resolved spectroscopy. The improved spectral resolution and efficiency over previous instruments makes possible measurements of previously undetectable lines, and the broad bandpass allows simultaneous measurements of lines from oxygen through iron. C1 NASA,GODDARD SPACE FLIGHT CTR,USRA,GREENBELT,MD 20771. UNIV MARYLAND,COLL PK,MD 20742. RP PETRE, R (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,CODE 666,GREENBELT,MD 20771, USA. RI Jahoda, Keith/D-5616-2012; Ptak, Andrew/D-3574-2012; Swank, Jean/F-2693-2012; Kelley, Richard/K-4474-2012 NR 23 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 57 EP 66 DI 10.1016/0273-1177(93)90097-U PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00007 ER PT S AU AWAKI, H KOYAMA, K AF AWAKI, H KOYAMA, K BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI GINGA OBSERVATIONS OF SEYFERT-GALAXIES SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT ID X-RAY; EMISSION; SPECTROPOLARIMETRY; REFLECTION; STARBURST; NGC-1068 AB We observed twenty-eight Seyfert 2 galaxies with the Japanese X-ray satellite, Ginga, and found Seyfert 2 galaxies, in general, have the X-ray spectral characteristics of obscured Seyfert 1 nuclei. This result agrees with the predictions from Unified Seyfert model proposed by Antonucci and Miller/1/. However, among the observed Seyfert 2 galaxies, there are a few galaxies with no evidence of an obscuration, contrary to the general predictions of the unified model. We note that type 2 AGN will contribute to the Cosmic Diffuse X-ray Background, if the unified Seyfert model can be extended to the far distant AGN such as quasars. C1 KYOTO UNIV,DEPT PHYS,SAKYO KU,KYOTO 606,JAPAN. RP AWAKI, H (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 666,GREENBELT,MD 20771, USA. NR 31 TC 33 Z9 33 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 221 EP 230 DI 10.1016/0273-1177(93)90114-Q PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00024 ER PT S AU JAHODA, K AF JAHODA, K BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI HEAO-1 AND BBXRT NON-SOURCE X-RAY OBSERVATIONS SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT AB A more appropriate title for this talk would have been ''Measurements of Large Scale Structure from X-ray Background Fluctuations''. While it has long been recognized that the X-ray Background (XRB) is primarily of a cosmological origin (with z < a few), it has recently become apparent that surface brightness fluctuations in the surveys of the XRB can be used to trace the distribution of matter in much the same way as complete catalogs of individual objects. The distance which is probed is related to the angular resolution of the detector, for the HEAO-1 A2 experiment, which provides the best all-sky data base for the XRB in the 2-20 keV band, the effective depth is a few 100 Mpc. RP JAHODA, K (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,CODE 666,GREENBELT,MD 20771, USA. RI Jahoda, Keith/D-5616-2012 NR 21 TC 15 Z9 14 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 231 EP 240 DI 10.1016/0273-1177(93)90115-R PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00025 ER PT S AU CORCORAN, MF SHORE, SN SWANK, JH HEAP, SR RAWLEY, GL POLLOCK, AMT STEVENS, IR AF CORCORAN, MF SHORE, SN SWANK, JH HEAP, SR RAWLEY, GL POLLOCK, AMT STEVENS, IR BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI X-RAY VARIABILITY IN V444 CYGNI - EVIDENCE FOR COLLIDING WINDS SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT AB Phase-resolved ROSAT observations of the soft X-ray flux from V444 Cygni confirm the orbital dependence of the flux suggested by analysis of IPC observations. The X-ray behavior suggests that a region of X-ray emitting gas exists between the 2 stars, probably produced by a collision between the WR and O star winds. C1 APPL RES CORP,LANDOVER,MD 20785. UNIV CAMBRIDGE,INST ASTRON,CAMBRIDGE CB3 0HA,ENGLAND. RP CORCORAN, MF (reprint author), NASA,GODDARD SPACE FLIGHT CTR,USRA,CODE 668,GREENBELT,MD 20771, USA. RI heap, sara/E-2237-2012; Swank, Jean/F-2693-2012 NR 2 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 295 EP 297 DI 10.1016/0273-1177(93)90124-T PG 3 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00034 ER PT S AU PARMAR, AN REYNOLDS, AP WHITE, NE AF PARMAR, AN REYNOLDS, AP WHITE, NE BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI THE LUMINOSITY DEPENDENCE OF THE PHASE-AVERAGED X-RAY-SPECTRUM OF THE TRANSIENT 42 SECOND PULSAR EXO2030+375 SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT ID DISCOVERY; HERCULES-X-1; EXO-2030+375 AB We report on the evolution in the X-ray spectrum of the transient X-ray pulsar EXO 2030+375 during part of an outburst in 1985 May-August. The overall continuum spectral shape is similar to that of other accreting pulsars and can be represented by a power-law spectrum modified at low energies by significant absorption and at high-energies either by an exponential cut-off or by the effects of cyclotron scattering. As the luminosity decreased by a factor similar to 100, the X-ray spectrum became harder with the photon index decreasing from 1.83 +/- 0.01 to 1.29 +/- 0.01. In addition, the high-energy cutoff decreased from 20 to 10 keV during the same interval. If the cutoff is interpreted in terms of cyclotron resonance scattering, then this implies a magnetic field strength that decreased from 2.6 x 10(12) G to 1.3 x 10(12) G. This variation implies that the cutoff energy does not provide a reliable measure of the surface magnetic field strength in this system. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP PARMAR, AN (reprint author), EUROPEAN SPACE TECHNOL CTR,EUROPEAN SPACE AGCY,DEPT SPACE SCI,DIV ASTROPHYS,KEPLERLAAN 1,2200 AG NOORDWIJK,NETHERLANDS. RI White, Nicholas/B-6428-2012 OI White, Nicholas/0000-0003-3853-3462 NR 18 TC 1 Z9 2 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 355 EP 360 DI 10.1016/0273-1177(93)90139-3 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00049 ER PT S AU TURNER, TJ GEORGE, IM MUSHOTZKY, RF AF TURNER, TJ GEORGE, IM MUSHOTZKY, RF BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI ROSAT PSPC SPECTRA OF 6 SEYFERT-1 GALAXIES SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT ID X-RAY REFLECTION; COLD MATTER; NUCLEI AB We present six ROSAT PSPC observations of Seyfert 1 galaxies chosen to have low Galactic line-of-sight absorption (N-H similar to 10(20) cm(-2)). As expected, it is found that all of these sources possess significantly steeper spectra below similar to 1 keV, than that observed at higher X-ray energies. In addition we find evidence for soft X-ray spectral features, which are best parameterized as line emission at similar to 0.63 keV in NGC7469 and similar to 0.75 keV in ESO198-G24. We examine these results in the light of the accuracy of the PSPC spectral calibration. We suggest that Seyfert galaxies are a class of object whose spectra are similar to the diffuse X-ray background in the soft X-ray band. We suggest these data provide the first direct evidence that the sources which dominate the background differ as a function of energy. These results are discussed more fully in a paper submitted to Ap.J./1/. C1 UNIV SPACE RES ASSOC,GREENBELT,MD. RP TURNER, TJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,CODE 668,GREENBELT,MD 20771, USA. NR 19 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 387 EP 390 DI 10.1016/0273-1177(93)90146-3 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00056 ER PT S AU BENNETT, CL BOGGESS, NW CHENG, ES HAUSER, MG KELSALL, T MATHER, JC MOSELEY, SH MURDOCK, TL SHAFER, RA SILVERBERG, RF SMOOT, GF WEISS, R WRIGHT, EL AF BENNETT, CL BOGGESS, NW CHENG, ES HAUSER, MG KELSALL, T MATHER, JC MOSELEY, SH MURDOCK, TL SHAFER, RA SILVERBERG, RF SMOOT, GF WEISS, R WRIGHT, EL BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI SCIENTIFIC RESULTS FROM COBE SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT ID COSMIC-BACKGROUND-RADIATION; DIFFERENTIAL MICROWAVE RADIOMETERS; INFLATIONARY UNIVERSE SCENARIO; COLD DARK MATTER; SCALE ANISOTROPIES; EXPLORER COBE; SPECTRUM; LIGHT; PERTURBATIONS; FLUCTUATIONS AB NASA's Cosmic Background Explorer (COBE(1)) carries three scientific instruments to make precise measurements of the spectrum and anisotropy of the cosmic microwave background (CMB) radiation on angular scales greater than 7 degrees and to conduct a search for a diffuse cosmic infrared background (CIB) radiation with 0.7 degrees angular resolution. Data from the Far-InfraRed Absolute Spectrophotometer (FIRAS) show that the spectrum of the CMB is that of a blackbody of temperature T=2.73+/-0.08 It, with no deviation from a blackbody spectrum greater than 0.25% of the peak brightness. The first year of data from the Differential Microwave Radiometers (DMR) show statistically significant CMB anisotropy. The anisotropy is consistent with a scale invariant primordial density fluctuation spectrum. Infrared sky brightness measurements from the Diffuse InfraRed Background Experiment (DIRBE) provide new conservative upper limits to the CIB. Extensive modeling of solar system anti galactic infrared foregrounds is required for further improvement in the CIB limits. C1 GEN RES CORP,DANVERS,MA 01923. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. UNIV CALIF LOS ANGELES,DEPT ASTRON,LOS ANGELES,CA 90024. RP BENNETT, CL (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 685,GREENBELT,MD 20771, USA. RI Moseley, Harvey/D-5069-2012 NR 102 TC 2 Z9 2 U1 0 U2 2 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 409 EP 423 DI 10.1016/0273-1177(93)90150-A PG 15 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00059 ER PT S AU WERNER, MW BOTHWELL, M AF WERNER, MW BOTHWELL, M BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI THE SIRTF MISSION SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT AB This paper describes the status of NASA's Space Infrared Telescope Facility (SIRTF) program. SIRTF will be a cryogenically cooled observatory for infrared astronomy from space and is planned for launch early in the next decade. We discuss a newly modified baseline SIRTF mission and review the state of the detector technology which will provide the heart of SIRTFs scientific advances. RP WERNER, MW (reprint author), CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 10 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 521 EP 529 DI 10.1016/0273-1177(93)90160-D PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00069 ER PT S AU THRONSON, HA HAWARDEN, TG BALLY, J BURNELL, SJB PENNY, AJ RAPP, D AF THRONSON, HA HAWARDEN, TG BALLY, J BURNELL, SJB PENNY, AJ RAPP, D BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI EDISON AND RADIATIVELY-COOLED IR SPACE-OBSERVATORIES SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT AB Radiative cooling of IR space telescopes is an alternative to embedding within massive cryostats and should offer advantages for future missions, including longer life, larger aperture for a fixed spacecraft size, lower cost due to less complex engineering, and easier ground handling. Relatively simple analyses of conventional designs show that it is possible to achieve telescope temperatures in the range of 25 to 40 K at distances from the sun of about 1 AU. Lower temperatures may be possible with ''open'' designs or distant orbits. At similar to 25 K, an observatory will be limited by the celestial thermal background in the near- and mid-IR and by the confusion limit in the far-IR. We outline here our concept for a moderate aperture (similar to 1.75 m; Ariane 4 or Atlas launch) international space observatory for the next decade. C1 JOINT ASTRON CTR,HILO,HI 96720. UNIV COLORADO,BOULDER,CO 80309. JET PROP LAB,PASADENA,CA. RP THRONSON, HA (reprint author), WYOMING INFRARED OBSERV,LARAMIE,WY, USA. RI Thronson, Harley/E-3382-2012 NR 5 TC 0 Z9 0 U1 0 U2 2 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 531 EP 534 DI 10.1016/0273-1177(93)90161-4 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00070 ER PT S AU ERICKSON, EF DAVIDSON, JA AF ERICKSON, EF DAVIDSON, JA BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI SOFIA - STRATOSPHERIC OBSERVATORY FOR INFRARED ASTRONOMY SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposium E2, and the Topical Meeting of the COSPAR Interdisciplinary Scientific Commission E of the COSPAR 29th Plenary Meeting CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ASTRON UNION, INT ACAD ASTRONAUT AB SOFIA is a planned 2.5 meter telescope to be installed in a Boeing 747 aircraft and operated at altitudes from 41,000 to 46,000 feet. It will permit routine measurement of infrared radiation inaccessible from the ground-based sites, and observation of astronomical objects and transient events from anywhere in the world. The concept is based on 18 years of experience with NASA's Kuiper Airborne Observatory (KAO), which SOFIA would replace. RP ERICKSON, EF (reprint author), NASA,AMES RES CTR,MS 345-6,MOFFETT FIELD,CA 94035, USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES PY 1993 VL 13 IS 12 BP 549 EP 556 DI 10.1016/0273-1177(93)90164-7 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00073 ER PT S AU FICHTEL, CE BERTSCH, DL DINGUS, B HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA KWOK, PW LIN, YC MATTOX, JR MAYERHASSELWANDER, HA MICHELSON, PF VONMONTIGNY, C NOLAN, PL PINKAU, K ROTHERMEL, H SCHNEID, EJ SOMMER, M SREEKUMAR, P THOMPSON, DJ AF FICHTEL, CE BERTSCH, DL DINGUS, B HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA KWOK, PW LIN, YC MATTOX, JR MAYERHASSELWANDER, HA MICHELSON, PF VONMONTIGNY, C NOLAN, PL PINKAU, K ROTHERMEL, H SCHNEID, EJ SOMMER, M SREEKUMAR, P THOMPSON, DJ BE Trumper, J Cesarsky, C Palumbo, GGC Bignami, GF TI RESULTS FROM THE ENERGETIC GAMMA-RAY EXPERIMENT TELESCOPE (EGRET) ON THE COMPTON GAMMA-RAY OBSERVATORY SO SPACE ASTRONOMY SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Review ID ACTIVE GALACTIC NUCLEI; MAGELLANIC CLOUD; VELA PULSAR; COSMIC-RAYS; X-RAY; RADIATION; GEMINGA; NEBULA; JETS AB The Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory covers the high energy gamma ray energy range, approximately 30 MeV to 30 GeV, with a sensitivity considerably greaterater than earlier high energy gamma-my satellites. Thus far, 4 pulsars have Seen detected and their properties measured, including in 3 cases the energy spectrum as a function of phase. The details of the galactic plane are being mapped and a spectra of the center region has been obtained in good agreement with that expected from cosmic ray interactions. The Magellanic clouds have been examined with the Large Magellanic Cloud having been detected at a level consistent with it having a cosmic ray density compatible with quasi-stable equilibrium. Sixteen Active Galactic Nuclei (AGN's) have been seen thus far with a high degree of certainty including 12 quasars and 4 BL Lac objects, but no Seyferts. Time variation has been detected in some of these AGN's. C1 MAX PLANCK INST EXTRATERR PHYS, W-8046 GARCHING, GERMANY. STANFORD UNIV, HANSEN EXPTL PHYS LAB, STANFORD, CA 94305 USA. GRUMMAN AEROSP CORP, BETHPAGE, NY 11714 USA. HAMPDEN SYDNEY COLL, HAMPDEN SYDNEY, VA 23943 USA. USRA RES ASSOCIATES, NRC, WASHINGTON, DC USA. RP NASA, GODDARD SPACE FLIGHT CTR, CODE 662, GREENBELT, MD 20771 USA. RI Nolan, Patrick/A-5582-2009; Hunter, Stanley/D-2942-2012; Thompson, David/D-2939-2012 OI Thompson, David/0000-0001-5217-9135 NR 52 TC 3 Z9 3 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 BN 0-08-042353-1 J9 ADV SPACE RES-SERIES PY 1993 VL 13 IS 12 BP 637 EP 646 DI 10.1016/0273-1177(93)90175-B PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BZ58Q UT WOS:A1993BZ58Q00083 ER PT S AU STANSBERY, EG BOHANNON, G PITTS, C TRACY, T STANLEY, J AF STANSBERY, EG BOHANNON, G PITTS, C TRACY, T STANLEY, J BE Flury, W TI RADAR OBSERVATIONS OF SMALL SPACE DEBRIS SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Proceedings Paper CT SCIENTIFIC MEETING ON SPACE DEBRIS, AT THE COSPAR 29TH PLENARY MEETING CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ACAD ASTRONAUT, INT ASTRONAUT FEDERAT RP STANSBERY, EG (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058, USA. NR 0 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA OXFORD SN 0273-1177 J9 ADV SPACE RES PY 1993 VL 13 BP 43 EP 48 DI 10.1016/0273-1177(93)90566-T PG 6 WC Engineering, Aerospace SC Engineering GA BY61Y UT WOS:A1993BY61Y00004 ER PT S AU ARNDT, GD FINK, P WARREN, WB AF ARNDT, GD FINK, P WARREN, WB BE Flury, W TI A SPACE STATION-BASED ORBITAL DEBRIS TRACKING SYSTEM SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Proceedings Paper CT SCIENTIFIC MEETING ON SPACE DEBRIS, AT THE COSPAR 29TH PLENARY MEETING CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ACAD ASTRONAUT, INT ASTRONAUT FEDERAT RP ARNDT, GD (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058, USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA OXFORD SN 0273-1177 J9 ADV SPACE RES PY 1993 VL 13 BP 65 EP 68 DI 10.1016/0273-1177(93)90569-W PG 4 WC Engineering, Aerospace SC Engineering GA BY61Y UT WOS:A1993BY61Y00007 ER PT S AU ZOLENSKY, ME KINARD, WH AF ZOLENSKY, ME KINARD, WH BE Flury, W TI RESULTS OF THE LDEF METEOROID AND DEBRIS SPECIAL INVESTIGATION GROUP SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Proceedings Paper CT SCIENTIFIC MEETING ON SPACE DEBRIS, AT THE COSPAR 29TH PLENARY MEETING CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ACAD ASTRONAUT, INT ASTRONAUT FEDERAT RP ZOLENSKY, ME (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,DIV SOLAR SYST EXPLORAT,HOUSTON,TX 77058, USA. NR 0 TC 5 Z9 5 U1 0 U2 6 PU PERGAMON PRESS LTD PI OXFORD PA OXFORD SN 0273-1177 J9 ADV SPACE RES PY 1993 VL 13 BP 75 EP 85 DI 10.1016/0273-1177(93)90571-R PG 11 WC Engineering, Aerospace SC Engineering GA BY61Y UT WOS:A1993BY61Y00009 ER PT S AU KESSLER, DJ AF KESSLER, DJ BE Flury, W TI ORBITAL DEBRIS ENVIRONMENT IN LOW-EARTH-ORBIT - AN UPDATE SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Proceedings Paper CT SCIENTIFIC MEETING ON SPACE DEBRIS, AT THE COSPAR 29TH PLENARY MEETING CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ACAD ASTRONAUT, INT ASTRONAUT FEDERAT RP KESSLER, DJ (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058, USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA OXFORD SN 0273-1177 J9 ADV SPACE RES PY 1993 VL 13 BP 139 EP 148 DI 10.1016/0273-1177(93)90581-U PG 10 WC Engineering, Aerospace SC Engineering GA BY61Y UT WOS:A1993BY61Y00019 ER PT S AU ANZMEADOR, PD RAST, RH POTTER, AE AF ANZMEADOR, PD RAST, RH POTTER, AE BE Flury, W TI APPARENT DENSITIES OF ORBITAL DEBRIS SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Proceedings Paper CT SCIENTIFIC MEETING ON SPACE DEBRIS, AT THE COSPAR 29TH PLENARY MEETING CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ACAD ASTRONAUT, INT ASTRONAUT FEDERAT RP ANZMEADOR, PD (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,SPACE SCI BRANCH,SN3,HOUSTON,TX 77058, USA. NR 0 TC 2 Z9 2 U1 1 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA OXFORD SN 0273-1177 J9 ADV SPACE RES PY 1993 VL 13 BP 153 EP 156 DI 10.1016/0273-1177(93)90583-W PG 4 WC Engineering, Aerospace SC Engineering GA BY61Y UT WOS:A1993BY61Y00021 ER PT S AU CHRISTIANSEN, EL ROBINSON, JH CREWS, JL OLSEN, GD VILAS, F AF CHRISTIANSEN, EL ROBINSON, JH CREWS, JL OLSEN, GD VILAS, F BE Flury, W TI SPACE STATION FREEDOM DEBRIS PROTECTION TECHNIQUES SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Proceedings Paper CT SCIENTIFIC MEETING ON SPACE DEBRIS, AT THE COSPAR 29TH PLENARY MEETING CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ACAD ASTRONAUT, INT ASTRONAUT FEDERAT RP CHRISTIANSEN, EL (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058, USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA OXFORD SN 0273-1177 J9 ADV SPACE RES PY 1993 VL 13 BP 191 EP 200 DI 10.1016/0273-1177(93)90590-8 PG 10 WC Engineering, Aerospace SC Engineering GA BY61Y UT WOS:A1993BY61Y00028 ER PT S AU LOFTUS, JP ANZMEADOR, PD REYNOLDS, R AF LOFTUS, JP ANZMEADOR, PD REYNOLDS, R BE Flury, W TI ORBITAL DEBRIS MINIMIZATION AND MITIGATION TECHNIQUES SO SPACE DEBRIS SE ADVANCES IN SPACE RESEARCH LA English DT Proceedings Paper CT SCIENTIFIC MEETING ON SPACE DEBRIS, AT THE COSPAR 29TH PLENARY MEETING CY AUG 28-SEP 05, 1992 CL WASHINGTON, DC SP COMM SPACE RES, INT ACAD ASTRONAUT, INT ASTRONAUT FEDERAT RP LOFTUS, JP (reprint author), LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058, USA. NR 0 TC 2 Z9 2 U1 1 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA OXFORD SN 0273-1177 J9 ADV SPACE RES PY 1993 VL 13 BP 263 EP 282 DI 10.1016/0273-1177(93)90599-7 PG 20 WC Engineering, Aerospace SC Engineering GA BY61Y UT WOS:A1993BY61Y00037 ER PT J AU PARKER, JW AF PARKER, JW TI A DISSECTION OF 30-DORADUS AND A DISCUSSION OF OTHER MAGELLANIC CLOUD OB ASSOCIATIONS SO SPACE SCIENCE REVIEWS LA English DT Review DE 30-DORADUS; MAGELLANIC CLOUDS; MASSIVE STARS; MASS FUNCTION ID STELLAR CONTENT; 30-DORADUS; STARS AB I Present the results of ground-based and Hubble Space Telescope photometry and spectroscopy of the stars in the central region (roughly 7 x 7 arcmin) of 30 Doradus in the Large Magellanic Cloud (LMC). Using photometric data for over 2400 stars (complete to V almost-equal-to 18 mag), and spectroscopic observations of over 150 stars in the region, the best estimate of the initial mass function (IMF) yields a slope of GAMMA = -1.5 +/- 0.2 for masses > 12M., where the Salpeter slope is GAMMA = -1.35. I compare these results to other measurements of the IMF for OB associations in the Magellanic Clouds. RP PARKER, JW (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 17 TC 2 Z9 2 U1 0 U2 2 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. PY 1993 VL 66 IS 1-4 BP 55 EP 59 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NL418 UT WOS:A1993NL41800005 ER PT J AU SCHULTELADBECK, RE CLAYTON, GC LEITHERER, C DRISSEN, L ROBERT, C NOTA, A PARKER, JW AF SCHULTELADBECK, RE CLAYTON, GC LEITHERER, C DRISSEN, L ROBERT, C NOTA, A PARKER, JW TI WIND ASYMMETRIES IN MASSIVE STARS SO SPACE SCIENCE REVIEWS LA English DT Review DE LUMINOUS BLUE VARIABLES; B [E] STARS; POLARIZATION ID LARGE MAGELLANIC CLOUD; WAVELENGTH DEPENDENCE; P-CYGNI; POLARIZATION; CARINAE AB We are in the process of surveying the linear polarization in luminous, early-type stars. We here report on new observations of the B [e] stars S 18 and R 50, and of the Luminous Blue Variables HR Car, R 143, and HD 160529. Together with previously published data, these observations provide clear evidence for the presence of intrinsic polarization in 1 B[e] star (HD 34664) and in 5 LBVs (eta Car, P Cyg, R 127, AG Car, and HR Car). The data indicate that anisotropic stellar winds are a common occurrence among massive stars in these particular evolutionary stages. For such stars, mass-loss rates estimated using the assumption of a spherical, homogeneous and stationary outflow may be in error. C1 UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,BOULDER,CO 80309. SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP SCHULTELADBECK, RE (reprint author), UNIV PITTSBURGH,DEPT PHYS & ASTRON,PITTSBURGH,PA 15260, USA. NR 27 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 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PY 1993 VL 66 IS 1-4 BP 193 EP 198 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NL418 UT WOS:A1993NL41800024 ER PT J AU WHEELER, JC SWARTZ, DA AF WHEELER, JC SWARTZ, DA TI THE EVOLUTION OF MASSIVE STARS TO EXPLOSION SO SPACE SCIENCE REVIEWS LA English DT Review DE STARS; SUPERNOVAE ID SUPERNOVA LIGHT CURVES; GIANT BRANCH STARS; II SUPERNOVAE; IB SUPERNOVAE; MODELS; HELIUM; LITHIUM; SPECTRA; EMISSION; NOVAE AB We review the possible evolutionary paths from massive stars to explosive endpoints as various types of supernovae associated with Population I and hence with massive stars: Type II-P, Type II-L, Type Ib, Type Ic, and the hybrid events SN 1987K and SN 1993J. We identify SN 1954A as another hybrid event from the evidence for both H and He in its spectrum with velocities nearly the same as SN 1983J. Evidence for ejected Ni-58 mass of approximately 0.07 M. suggests that SN II-P underwent standard iron core collapse, not collapse of an O-Ne-Mg core nor thermonuclear explosion of a C-O core. Most SN II-P presumably arise in single stars or wide binaries of approximately 10 - 20 M.. There may be indirect evidence for duplicity in some cases in the form of strong Ba II lines, such as characterized SN 1987A. SN II-L are recognizably distinct from typical SN II-P and must undergo a significantly different evolution. Despite indications that SN II-L have small envelopes that may be helium enriched, they are also distinct from events like SN 1993J that must have yet again a different evolution. The SN II-L that share a common luminosity seem to have ejected a small nickel mass and hence may come from stars with O-Ne-Mg cores. The amount of nickel ejected by the exceptionally bright events, SN 1980K and SN 1979C, remains controversial. SN Ib require the complete loss of the H envelope, either to a binary companion or to a wind. The few identified have relatively large ejecta masses. It is not clear what evolutionary processes distinguish SN Ib's evolving in binary systems from hybrid events that retain some H in the envelope. SN Ic events are both H and He deficient. Binary models that can account for transfer of an extended helium envelope from low mass helium cores, approximately 2 to 4 M., imply C-O core-masses that are roughly consistent with that deduced from the ejecta mass plus a neutron star, approximately 2 to 3 M.. It is possible that the hybrid events are the result of Roche lobe overflow and that the ''pure'' events, SN Ib or SN Ic, result from common envelope evolution. C1 NASA, GEORGE C MARSHALL SPACE FLIGHT CTR, XRAY ASTRON BRANCH, HUNTSVILLE, AL 35812 USA. RP WHEELER, JC (reprint author), UNIV TEXAS, DEPT ASTRON, AUSTIN, TX 78712 USA. NR 63 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PY 1993 VL 66 IS 1-4 BP 425 EP 437 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NL418 UT WOS:A1993NL41800056 ER PT B AU GUPTA, KK AF GUPTA, KK BE Parke, GAR Howard, CM TI MULTIDISCIPLINARY MODELING AND ANALYSIS OF AEROSPACE STRUCTURES SO SPACE STRUCTURES 4, VOL 1 LA English DT Proceedings Paper CT 4th International Conference on Space Structures CY SEP 05-10, 1993 CL UNIV SURREY, GUILDFORD, ENGLAND SP UNIV SURREY, SPACE STRUCT RES CTR HO UNIV SURREY C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU THOMAS TELFORD SERVICES LTD PI LONDON PA THOMAS TELFORD HOUSE, 1 HERON QUAY, LONDON, ENGLAND E14 4JD BN 0-7277-1968-8 PY 1993 BP 38 EP 50 PG 13 WC Engineering, Aerospace; Construction & Building Technology SC Engineering; Construction & Building Technology GA BB63Y UT WOS:A1993BB63Y00005 ER PT J AU AUSTIN, RE AF AUSTIN, RE TI DESIGNING THE SPACE TRANSFER VEHICLE (STV) SO SPACE TECHNOLOGY-INDUSTRIAL AND COMMERCIAL APPLICATIONS LA English DT Article AB This paper describes the overall Space Transfer Vehicle (STV) Study and specifically the concept definition approach which the Boeing Aerospace and Electronics Company is performing for NASA Marshall Space Flight Center. RP AUSTIN, RE (reprint author), NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,HUNTSVILLE,AL 35812, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0892-9270 J9 SPACE TECHNOL JI Space Tech.-Ind. Comm. Appl. PD JAN PY 1993 VL 13 IS 1 BP 1 EP 10 PG 10 WC Engineering, Aerospace SC Engineering GA JX582 UT WOS:A1993JX58200001 ER PT J AU HARRIS, LA AMBRUS, JH HEMMERLY, RA AF HARRIS, LA AMBRUS, JH HEMMERLY, RA TI IN-SPACE TECHNOLOGY EXPERIMENTS PREREQUISITE FOR MISSIONS OF THE FUTURE SO SPACE TECHNOLOGY-INDUSTRIAL AND COMMERCIAL APPLICATIONS LA English DT Article AB Experience with the Shuttle and free-flying satellites as technology test beds has shown the feasibility and desirability of using space assets as facilities for technology development. Thus, with the arrival of the Space Station Freedom era, technologists will be ready for an accessible engineering facility in space, particularly to support technology development for manned space exploration. As the 21st century is approached, virtually every flight to the Space Station Freedom will carry one or more RT&E experiments. The experiments planned will utilize both the pressurized volume and the external attachment facilities. A unique class of experiments will use the space station itself as an experimental test bed. Based upon recent examination of possible space station assembly sequences, technology payloads may utilize upwards of 20% of available resources. RP HARRIS, LA (reprint author), NASA,OFF AERONAUT EXPLORAT & TECHNOL,WASHINGTON,DC 20546, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0892-9270 J9 SPACE TECHNOL JI Space Tech.-Ind. Comm. Appl. PD JAN PY 1993 VL 13 IS 1 BP 37 EP 51 PG 15 WC Engineering, Aerospace SC Engineering GA JX582 UT WOS:A1993JX58200005 ER PT B AU MELODY, JW BRIGGS, HC AF MELODY, JW BRIGGS, HC BE Reasenberg, RD TI ANALYSIS OF STRUCTURAL AND OPTICAL INTERACTIONS OF THE PRECISION OPTICAL INTERFEROMETER IN-SPACE (POINTS) SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 6 Z9 6 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 44 EP 57 DI 10.1117/12.155752 PG 14 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00004 ER PT B AU SCHUMAKER, B AGRONIN, M CHEN, GS LEDEBOER, W MELODY, J NOON, D ULVESTAD, J AF SCHUMAKER, B AGRONIN, M CHEN, GS LEDEBOER, W MELODY, J NOON, D ULVESTAD, J BE Reasenberg, RD TI SPACECRAFT AND MISSION DESIGN FOR THE PRECISION OPTICAL INTERFEROMETER IN-SPACE (POINTS) SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 58 EP 72 DI 10.1117/12.155747 PG 15 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00005 ER PT B AU SHAO, M AF SHAO, M BE Reasenberg, RD TI ORBITING STELLAR INTERFEROMETER SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 3 Z9 3 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 89 EP 90 DI 10.1117/12.155755 PG 2 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00008 ER PT B AU NEAT, GW SWORD, LF HINES, BE CALVET, RJ AF NEAT, GW SWORD, LF HINES, BE CALVET, RJ BE Reasenberg, RD TI MICRO-PRECISION INTERFEROMETER TESTBED - END-TO-END SYSTEM INTEGRATION OF CONTROL-STRUCTURE INTERACTION TECHNOLOGIES SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 2 Z9 2 U1 1 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 91 EP 103 DI 10.1117/12.155756 PG 13 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00009 ER PT B AU SWORD, LF CARNE, TG AF SWORD, LF CARNE, TG BE Reasenberg, RD TI PRECISION TRUSS STRUCTURES FROM CONCEPT TO HARDWARE REALITY - APPLICATION TO THE MICRO-PRECISION INTERFEROMETER TESTBED SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 1 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 104 EP 113 DI 10.1117/12.155735 PG 10 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00010 ER PT B AU HINES, B AF HINES, B BE Reasenberg, RD TI OPTICAL DESIGN ISSUES FOR THE MICRO-PRECISION INTERFEROMETER TESTBED FOR SPACE-BASED INTERFEROMETRY SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 114 EP 125 DI 10.1117/12.155736 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00011 ER PT B AU CALVET, RJ OBRIEN, JF NEAT, GW AF CALVET, RJ OBRIEN, JF NEAT, GW BE Reasenberg, RD TI VALIDATION OF AN INTEGRATED MODELING TOOL APPLIED TO THE MICRO-PRECISION INTERFEROMETER TESTBED SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 1 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 126 EP 138 DI 10.1117/12.155737 PG 13 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00012 ER PT B AU AGRONIN, M AF AGRONIN, M BE Reasenberg, RD TI PRECISION ACTUATORS FOR SPACEBORNE INTERFEROMETERS - A TUTORIAL SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 140 EP 160 DI 10.1117/12.155738 PG 21 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00013 ER PT B AU GURSEL, Y AF GURSEL, Y BE Reasenberg, RD TI LASER METROLOGY GAUGES FOR OSI SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 27 Z9 28 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 188 EP 197 DI 10.1117/12.155740 PG 10 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00016 ER PT B AU HINES, B AF HINES, B BE Reasenberg, RD TI OPTICAL TRUSS AND RETROREFLECTOR MODELING FOR PICOMETER LASER METROLOGY SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 8 Z9 8 U1 0 U2 2 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 198 EP 208 DI 10.1117/12.155741 PG 11 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00017 ER PT B AU YU, J SHAKLAN, S SHAO, M AF YU, J SHAKLAN, S SHAO, M BE Reasenberg, RD TI HIGH-PRECISION ASTROMETRY OF CROWDED FIELDS BY INTERFEROMETRY SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 209 EP 217 DI 10.1117/12.155742 PG 9 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00018 ER PT B AU DOLGIN, BP AF DOLGIN, BP BE Reasenberg, RD TI DIMENSIONALLY STABLE MATERIALS FOR SPACE INTERFEROMETERS SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 234 EP 248 DI 10.1117/12.155744 PG 15 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00020 ER PT B AU YU, J SHAO, M COLAVITA, M RAYMAN, M AF YU, J SHAO, M COLAVITA, M RAYMAN, M BE Reasenberg, RD TI DESIGN OF AN ORBITING STELLAR INTERFEROMETER FOR PLANET DETECTION SO SPACEBORNE INTERFEROMETRY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spaceborne Interferometry CY APR 15-16, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1183-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 1947 BP 261 EP 271 DI 10.1117/12.155743 PG 11 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BZ81S UT WOS:A1993BZ81S00022 ER PT S AU ESTEFAN, JA POLLMEIER, VM THURMAN, SW AF ESTEFAN, JA POLLMEIER, VM THURMAN, SW BE Teles, J Samii, MV TI PRECISION X-BAND DOPPLER AND RANGING NAVIGATION FOR CURRENT AND FUTURE MARS EXPLORATION MISSIONS SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 JET PROP LAB,NAVIGAT SYST SECT,PASADENA,CA 91109. NR 0 TC 3 Z9 3 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 3 EP 16 PN 1-2 PG 14 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00001 ER PT S AU POLLMEIER, VM KALLEMEYN, PH THURMAN, SW AF POLLMEIER, VM KALLEMEYN, PH THURMAN, SW BE Teles, J Samii, MV TI APPLICATION OF HIGH-PRECISION 2-WAY S-BAND RANGING TO THE NAVIGATION OF THE GALILEO EARTH ENCOUNTERS SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 JET PROP LAB,NAVIGAT SYST SECT,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 17 EP 30 PN 1-2 PG 14 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00002 ER PT S AU GRAMLING, CJ HART, RC TELES, J LONG, AC MAHER, MJ AF GRAMLING, CJ HART, RC TELES, J LONG, AC MAHER, MJ BE Teles, J Samii, MV TI PERFORMANCE ASSESSMENT OF THE TDRSS ONBOARD NAVIGATION SYSTEM (TONS) EXPERIMENT ON EP EUVE SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GSFC,FLIGHT DYNAM SUPPORT BRANCH,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 93 EP 108 PN 1-2 PG 16 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00007 ER PT S AU FOLTA, DC ELROD, B LORENZ, M KAPOOR, A AF FOLTA, DC ELROD, B LORENZ, M KAPOOR, A BE Teles, J Samii, MV TI PRECISE NAVIGATION FOR THE EARTH OBSERVING SYSTEM (EOS)-AM1 SPACECRAFT USING THE TDRSS ONBOARD NAVIGATION SYSTEM (TONS) SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GSFC,DIV FLIGHT DYNAM,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 109 EP 123 PN 1-2 PG 15 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00008 ER PT S AU BECKMAN, M YEE, C LEE, T HOPPE, M OZA, D AF BECKMAN, M YEE, C LEE, T HOPPE, M OZA, D BE Teles, J Samii, MV TI ORBIT DETERMINATION COVARIANCE ANALYSIS FOR THE DEEP SPACE PROGRAM SCIENCE EXPERIMENT MISSION SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GSFC,GREENBELT,MD 20771. NR 0 TC 0 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 173 EP 187 PN 1-2 PG 15 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00012 ER PT S AU YEOMANS, DK AF YEOMANS, DK BE Teles, J Samii, MV TI TARGETING AN ASTEROID THE DSPSE ENCOUNTER WITH ASTEROID-1620 GEOGRAPHOS SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 JET PROP LAB,SOLAR SYST DYNAM GRP,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 189 EP 196 PN 1-2 PG 8 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00013 ER PT S AU DOLL, C MISTRETTA, G HART, R OZA, D COX, C NEMESURE, M BOLVIN, D SAMII, M AF DOLL, C MISTRETTA, G HART, R OZA, D COX, C NEMESURE, M BOLVIN, D SAMII, M BE Teles, J Samii, MV TI COMPARISON OF TOPEX POSEIDON ORBIT DETERMINATION SOLUTIONS OBTAINED BY THE GODDARD-SPACE-FLIGHT-CENTER FLIGHT DYNAMICS DIVISION AND PRECISION ORBIT DETERMINATION TEAMS SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GSFC,GREENBELT,MD 20771. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 221 EP 235 PN 1-2 PG 15 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00016 ER PT S AU TELES, J PUTNEY, B PHELPS, J MCCARTHY, J EDDY, W KLOSKO, S AF TELES, J PUTNEY, B PHELPS, J MCCARTHY, J EDDY, W KLOSKO, S BE Teles, J Samii, MV TI PRECISION ORBIT DETERMINATION USING TOPEX POSEIDON TDRSS OBSERVATIONS SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 249 EP 263 PN 1-2 PG 15 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00018 ER PT S AU MARSHALL, JA LUTHCKE, SB AF MARSHALL, JA LUTHCKE, SB BE Teles, J Samii, MV TI CONSERVATIVE FORCE MODEL PERFORMANCE FOR TOPEX POSEIDON PRECISION ORBIT DETERMINATION SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,SPACE GEODESY BRANCH,GREENBELT,MD 20771. RI Luthcke, Scott/D-6283-2012 NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 265 EP 278 PN 1-2 PG 14 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00019 ER PT S AU SHARER, P ZSOLDOS, J FOLTA, D AF SHARER, P ZSOLDOS, J FOLTA, D BE Teles, J Samii, MV TI CONTROL OF LIBRATION POINT ORBITS USING LUNAR GRAVITY-ASSISTED TRANSFER SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NR 0 TC 2 Z9 3 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 651 EP 663 PN 1-2 PG 13 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00046 ER PT S AU MARKLEY, FL BERMAN, N SHAKED, U AF MARKLEY, FL BERMAN, N SHAKED, U BE Teles, J Samii, MV TI H-INFINITY-TYPE FILTER FOR SPACECRAFT ATTITUDE ESTIMATION SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 697 EP 711 PN 1-2 PG 15 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00049 ER PT S AU HARMAN, R LEE, M AF HARMAN, R LEE, M BE Teles, J Samii, MV TI EXTREME-ULTRAVIOLET EXPLORER ATTITUDE DETERMINATION SUPPORT WITH A MULTIMISSION 3-AXIS STABILIZED SPACECRAFT FLIGHT DYNAMICS SUPPORT SYSTEM SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,DIV FLIGHT DYNAM,GREENBELT,MD 20771. NR 0 TC 1 Z9 1 U1 0 U2 1 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 763 EP 777 PN 1-2 PG 15 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00053 ER PT S AU NEWMAN, LK FOLTA, DC ROSS, BP BOUSLOG, SA AF NEWMAN, LK FOLTA, DC ROSS, BP BOUSLOG, SA BE Teles, J Samii, MV TI REENTRY ANALYSIS FOR LOW EARTH ORBITING SPACECRAFT SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,DIV FLIGHT DYNAM,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 835 EP 846 PN 1-2 PG 12 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00058 ER PT S AU KETCHUM, EA TOLSON, RH AF KETCHUM, EA TOLSON, RH BE Teles, J Samii, MV TI LOST IN-SPACE - ONBOARD STAR IDENTIFICATION USING CCD STAR TRACKER DATA WITHOUT AN A-PRIORI ATTITUDE SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,DIV FLIGHT DYNAM,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 1101 EP 1113 PN 1-2 PG 13 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00077 ER PT S AU MARKLEY, FL AF MARKLEY, FL BE Teles, J Samii, MV TI NEW DYNAMIC VARIABLES FOR ROTATING SPACECRAFT SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,GUIDANCE & CONTROL BRANCH,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 1149 EP 1163 PN 1-2 PG 15 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00080 ER PT S AU CROUSE, P LEWIS, M AF CROUSE, P LEWIS, M BE Teles, J Samii, MV TI THE EFFECT OF HIGH LIFT TO DRAG RATIO ON AEROBRAKING SO SPACEFLIGHT DYNAMICS 1993, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/NASA International Symposium: Spaceflight Dynamics 1993 CY APR 26-30, 1993 CL GREENBELT, MD SP AMER ASTRONAUT SOC, NASA C1 NASA,GODDARD SPACE FLIGHT CTR,DIV FLIGHT DYNAM,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-378-1 J9 ADV ASTRONAUT SCI PY 1993 VL 84 BP 1265 EP 1278 PN 1-2 PG 14 WC Engineering, Aerospace SC Engineering GA BA20M UT WOS:A1993BA20M00091 ER PT S AU SCHEERES, DJ VINH, NX AF SCHEERES, DJ VINH, NX BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI SATELLITE DYNAMICS ABOUT A PLANET WITH A NARROW RING SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 747 EP 764 PN 1-2 PG 18 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00045 ER PT S AU MUELLERSCHOEN, RJ BERTIGER, WI WU, SC AF MUELLERSCHOEN, RJ BERTIGER, WI WU, SC BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI GRAVITY RECOVERY ANALYSIS USING GPS FOR STEP AND A LOW-LOW SATELLITE MISSION SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 821 EP 832 PN 1-2 PG 12 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00049 ER PT S AU BERTIGER, W WU, S YUNCK, T MUELLERSCHOEN, R WILLIS, P BARSEVER, Y DAVIS, A HAINES, B MUNSON, T LICHTEN, S SUNSERI, R AF BERTIGER, W WU, S YUNCK, T MUELLERSCHOEN, R WILLIS, P BARSEVER, Y DAVIS, A HAINES, B MUNSON, T LICHTEN, S SUNSERI, R BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI EARLY RESULTS FROM THE TOPEX POSEIDON GPS PRECISE ORBIT DETERMINATION DEMONSTRATION SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,TRACKING SYST & APPLICAT SECT,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 863 EP 876 PN 1-2 PG 14 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00052 ER PT S AU CHRISTENSEN, EJ WILLIAMS, BG YUAN, DN MCCOLL, KC AF CHRISTENSEN, EJ WILLIAMS, BG YUAN, DN MCCOLL, KC BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI MODELING NON-GRAVITATIONAL FORCES ACTING ON TOPEX POSEIDON - THE EARLY DAYS SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,TRACKING SYST & APPLICAT SECT,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 877 EP 888 PN 1-2 PG 12 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00053 ER PT S AU WILLIAMS, BG CHRISTENSEN, EJ YUAN, DN MCCOLL, KC SUNSERI, RF AF WILLIAMS, BG CHRISTENSEN, EJ YUAN, DN MCCOLL, KC SUNSERI, RF BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI SHORT ARC ORBIT DETERMINATION FOR ALTIMETER CALIBRATION AND VALIDATION ON TOPEX POSEIDON SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,NAVIGAT SYST SECT,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 889 EP 899 PN 1-2 PG 11 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00054 ER PT S AU VIGUE, Y LICHTEN, SM MUELLERSCHOEN, RJ BLEWITT, G HEFLIN, MB AF VIGUE, Y LICHTEN, SM MUELLERSCHOEN, RJ BLEWITT, G HEFLIN, MB BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI IMPROVED TREATMENT OF GPS FORCE PARAMETERS IN PRECISE ORBIT DETERMINATION APPLICATIONS SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 929 EP 935 PN 1-2 PG 7 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00057 ER PT S AU LICHTEN, SM EDWARDS, CD YOUNG, LE NANDI, S DUNN, C HAINES, BJ AF LICHTEN, SM EDWARDS, CD YOUNG, LE NANDI, S DUNN, C HAINES, BJ BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI A DEMONSTRATION OF TDRS ORBIT DETERMINATION USING DIFFERENTIAL TRACKING OBSERVABLES FROM GPS GROUND RECEIVERS SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,TRACKING SYST & APPLICAT SECT,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 937 EP 954 PN 1-2 PG 18 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00058 ER PT S AU THURMAN, SW ESTEFAN, JA AF THURMAN, SW ESTEFAN, JA BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI RADIO DOPPLER NAVIGATION OF INTERPLANETARY SPACECRAFT USING DIFFERENT DATA-PROCESSING MODES SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,NAVIGAT SYST SECT,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 985 EP 1004 PN 1-2 PG 20 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00061 ER PT S AU KAHN, RD THURMAN, SW EDWARDS, CD AF KAHN, RD THURMAN, SW EDWARDS, CD BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI IN-SITU RADIO-METRIC TRACKING TO SUPPORT NAVIGATION FOR INTERPLANETARY MISSIONS WITH MULTIPLE SPACECRAFT SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 CALIFORNIA INST TECHNOL,JET PROPULS LAB,TRACKING SYSTEMS & APPLICAT SECT,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 1005 EP 1022 PN 1-2 PG 18 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00086 ER PT S AU KROGER, PM FOLKNER, WM IIJIMA, BA HILDEBRAND, CE AF KROGER, PM FOLKNER, WM IIJIMA, BA HILDEBRAND, CE BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI VERY-LONG-BASE-LINE-INTERFEROMETRY MEASUREMENTS OF PLANETARY ORBITERS AT MARS AND VENUS SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 1023 EP 1037 PN 1-2 PG 15 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00062 ER PT S AU IONASESCU, R SONNABEND, D AF IONASESCU, R SONNABEND, D BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI ASTEROID APPROACH COVARIANCE ANALYSIS FOR THE CLEMENTINE MISSION SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,NAVIGAT SYST SECT,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 1039 EP 1050 PN 1-2 PG 12 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00063 ER PT S AU FOLKNER, WM MCELRATH, TP AF FOLKNER, WM MCELRATH, TP BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI DETERMINATION OF RADIO-FRAME POSITION FOR EARTH AND JUPITER FROM ULYSSES ENCOUNTER TRACKING SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,TRACKING SYST & APPLICAT SECT,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 1051 EP 1059 PN 1-2 PG 9 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00064 ER PT S AU NANDI, S BORDER, JS FOLKNER, WM AF NANDI, S BORDER, JS FOLKNER, WM BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI DEMONSTRATION OF USE OF A REAL-TIME TONE TRACKER TO OBTAIN SAME BEAM INTERFEROMETRY DATA SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 1061 EP 1070 PN 1-2 PG 10 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00065 ER PT S AU EVANS, SW DUKEMAN, GA AF EVANS, SW DUKEMAN, GA BE Melton, RG Wood, LJ Thompson, RC Kerridge, SJ TI DESCRIPTION AND PERFORMANCE ANALYSIS OF A GENERALIZED OPTIMAL ALGORITHM FOR AEROBRAKING GUIDANCE SO SPACEFLIGHT MECHANICS 1993 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Spaceflight Mechanics Meeting CY FEB 22-24, 1993 CL PASADENA, CA SP AMER ASTRONAUT SOC, AMER INST AERONAUT & ASTRONAUT C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,FLIGHT MECH BRANCH,HUNTSVILLE,AL 35812. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 SN 0065-3438 BN 0-87703-368-4 J9 ADV ASTRONAUT SCI PY 1993 VL 82 BP 1089 EP 1108 PN 1-2 PG 20 WC Engineering, Aerospace; Mechanics SC Engineering; Mechanics GA BZ64V UT WOS:A1993BZ64V00067 ER PT B AU JEPSON, AD HEEGER, DJ AF JEPSON, AD HEEGER, DJ BE Harris, L Jenkin, M TI LINEAR SUBSPACE METHODS FOR RECOVERING TRANSLATIONAL DIRECTION SO SPATIAL VISION IN HUMANS AND ROBOTS: THE PROCEEDINGS OF THE 1991 YORK CONFERENCE ON SPATIAL VISION IN HUMANS AND ROBOTS LA English DT Proceedings Paper CT 1991 York Conference on Spatial Vision in Humans and Robots CY JUN 19-22, 1991 CL YORK UNIV, TORONTO, CANADA SP INST SPACE & TERRESTRIAL SCI, HUMAN PERFORMANCE IN SPACE LAB, INFORMAT TECHNOL RES CTR, YORK UNIV, DEPT COMP SCI, NATL SCI & ENGN RES SOUNCIL CANADA, YORK UNIV, PRESIDENTS NSERC FUND, YORK UNIV, FAC PURE & APPL SCI HO YORK UNIV C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 24 Z9 24 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1RP BN 0-521-43071-2 PY 1993 BP 39 EP 62 PG 24 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA BA72V UT WOS:A1993BA72V00004 ER PT B AU HEEGER, DJ SIMONCELLI, EP AF HEEGER, DJ SIMONCELLI, EP BE Harris, L Jenkin, M TI MODEL OF VISUAL-MOTION SENSING SO SPATIAL VISION IN HUMANS AND ROBOTS: THE PROCEEDINGS OF THE 1991 YORK CONFERENCE ON SPATIAL VISION IN HUMANS AND ROBOTS LA English DT Proceedings Paper CT 1991 York Conference on Spatial Vision in Humans and Robots CY JUN 19-22, 1991 CL YORK UNIV, TORONTO, CANADA SP INST SPACE & TERRESTRIAL SCI, HUMAN PERFORMANCE IN SPACE LAB, INFORMAT TECHNOL RES CTR, YORK UNIV, DEPT COMP SCI, NATL SCI & ENGN RES SOUNCIL CANADA, YORK UNIV, PRESIDENTS NSERC FUND, YORK UNIV, FAC PURE & APPL SCI HO YORK UNIV C1 STANFORD UNIV,NASA,AMES RES CTR,STANFORD,CA 94305. NR 0 TC 9 Z9 9 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1RP BN 0-521-43071-2 PY 1993 BP 367 EP 392 PG 26 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA BA72V UT WOS:A1993BA72V00019 ER PT J AU SUAREZ, CB CHACKERIAN, C VALERO, F AF SUAREZ, CB CHACKERIAN, C VALERO, F TI ABSOLUTE INTENSITIES OF SPECTRAL-LINES IN THE Q-BRANCH OF THE CH3D AT LOW-TEMPERATURE SO SPECTROSCOPY LETTERS LA English DT Article AB This study reports the experimental measurement of absolute intensities for individual lines of the Q branch in the nu2 band of CH3D near 2000 cm-1 at low temperature. High resolution infrared spectroscopy is a powerful tool for understanding the composition and dynamical structures of planetary atmospheres. In fact, CH3D has been detected in the atmospheres of Jupiter, Saturn and Titan, so accurate intensities for individual ro-vibrational lines are needed for determining CH3D abundance and the D/H ratio in planetary atmospheres. C1 CONSEJO NACL INVEST CIENT & TECN,RA-1900 LA PLATA,ARGENTINA. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RP SUAREZ, CB (reprint author), PROGRAMA QUINOR,CC 962,RA-1900 LA PLATA,ARGENTINA. NR 1 TC 1 Z9 1 U1 0 U2 1 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 SN 0038-7010 J9 SPECTROSC LETT JI Spectr. Lett. PY 1993 VL 26 IS 8 BP 1465 EP 1468 DI 10.1080/00387019308011624 PG 4 WC Spectroscopy SC Spectroscopy GA LX053 UT WOS:A1993LX05300010 ER PT J AU SUAREZ, CB CHACKERIAN, C VALERO, F AF SUAREZ, CB CHACKERIAN, C VALERO, F TI SELF-BROADENING COEFFICIENTS OF CH3D SPECTRAL-LINES IN THE P-BRANCH OF THE NU-2 BAND AT 2200 CM-1 SO SPECTROSCOPY LETTERS LA English DT Article DE SPECTROSCOPY-INFRARED SPECTRA-HALF-WIDTHS-FOURIER SPECTROSCOPY AB We report the pressure broadening coefficients of 18 lines of the P-branch of the nu2 band of CH3D near 2200 cm-1, obtained at room temperature, using a Fourier Transform spectrometer with a resolution of 0.006 cm-1. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. CONSEJO NACL INVEST CIENT & TECN,RA-1900 LA PLATA,ARGENTINA. RP SUAREZ, CB (reprint author), PROGRAMA QUINOR,CC 962,RA-1900 LA PLATA,ARGENTINA. NR 1 TC 4 Z9 4 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 SN 0038-7010 J9 SPECTROSC LETT JI Spectr. Lett. PY 1993 VL 26 IS 8 BP 1523 EP 1527 DI 10.1080/00387019308011630 PG 5 WC Spectroscopy SC Spectroscopy GA LX053 UT WOS:A1993LX05300016 ER PT B AU MORRISON, DA LAWRENCE, TW AF MORRISON, DA LAWRENCE, TW BE Clark, BP Douglas, A Foley, BL Huberty, B Whitmill, LD TI PREPARING THE WAY FOR PLANETARY EXPLORATION - THE LUNAR-SCOUT-PROGRAM SO STATE-OF-THE-ART MAPPING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT State-of-the-Art Mapping Conference CY APR 13-15, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AMER SOC PHOTOGRAMMETRY & REMOTE SENSING C1 NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1179-5 J9 P SOC PHOTO-OPT INS PY 1993 VL 1943 BP 2 EP 13 DI 10.1117/12.157131 PG 12 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BZ81Q UT WOS:A1993BZ81Q00001 ER PT B AU SMITH, DE ZUBER, MT ABSHIRE, JB AF SMITH, DE ZUBER, MT ABSHIRE, JB BE Clark, BP Douglas, A Foley, BL Huberty, B Whitmill, LD TI THE MARS OBSERVER LASER ALTIMETER INVESTIGATION SO STATE-OF-THE-ART MAPPING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT State-of-the-Art Mapping Conference CY APR 13-15, 1993 CL ORLANDO, FL SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AMER SOC PHOTOGRAMMETRY & REMOTE SENSING C1 NASA,GODDARD SPACE FLIGHT CTR,TERR PHYS LAB,GREENBELT,MD 20771. RI Abshire, James/I-2800-2013 NR 0 TC 0 Z9 0 U1 2 U2 2 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1179-5 J9 P SOC PHOTO-OPT INS PY 1993 VL 1943 BP 14 EP 18 DI 10.1117/12.157137 PG 5 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BZ81Q UT WOS:A1993BZ81Q00002 ER PT B AU NESBITT, JA BARRETT, CA AF NESBITT, JA BARRETT, CA BE Darolia, R Lewandowski, JJ Liu, CT Martin, PL Miracle, DB Nathal, MV TI PREDICTING THE OXIDATION-LIMITED LIFETIME OF BETA-NIAL SO STRUCTURAL INTERMETALLICS LA English DT Proceedings Paper CT 1st International Symposium on Structural Intermetallics CY SEP 26-30, 1993 CL CHAMPION, PA SP MINERALS MET & MAT SOC, HIGH TEMP ALLOYS COMM, AMER SOC MET INT, AMER SOC MECH ENGINEERS C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 13 Z9 13 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 BN 0-87339-253-1 PY 1993 BP 601 EP 609 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA BZ64C UT WOS:A1993BZ64C00065 ER PT B AU BRINDLEY, PK DRAPER, SL AF BRINDLEY, PK DRAPER, SL BE Darolia, R Lewandowski, JJ Liu, CT Martin, PL Miracle, DB Nathal, MV TI FAILURE MECHANISMS OF 0-DEGREES AND 90-DEGREES SIC/TI-24AL-11NB COMPOSITES UNDER VARIOUS LOADING CONDITIONS SO STRUCTURAL INTERMETALLICS LA English DT Proceedings Paper CT 1st International Symposium on Structural Intermetallics CY SEP 26-30, 1993 CL CHAMPION, PA SP MINERALS MET & MAT SOC, HIGH TEMP ALLOYS COMM, AMER SOC MET INT, AMER SOC MECH ENGINEERS C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 14 Z9 15 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 BN 0-87339-253-1 PY 1993 BP 727 EP 737 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA BZ64C UT WOS:A1993BZ64C00079 ER PT B AU WHITTENBERGER, JD AF WHITTENBERGER, JD BE Darolia, R Lewandowski, JJ Liu, CT Martin, PL Miracle, DB Nathal, MV TI CHARACTERISTICS OF AN ELEVATED-TEMPERATURE ALN PARTICULATE-REINFORCED NIAL SO STRUCTURAL INTERMETALLICS LA English DT Proceedings Paper CT 1st International Symposium on Structural Intermetallics CY SEP 26-30, 1993 CL CHAMPION, PA SP MINERALS MET & MAT SOC, HIGH TEMP ALLOYS COMM, AMER SOC MET INT, AMER SOC MECH ENGINEERS C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 16 Z9 16 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 BN 0-87339-253-1 PY 1993 BP 819 EP 828 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA BZ64C UT WOS:A1993BZ64C00089 ER PT B AU JONES, DL AF JONES, DL BE Davis, RJ Booth, RS TI NORTHERN HEMISPHERE VLBI OBSERVATIONS OF PKS 1830-211 SO SUB-ARCSECOND RADIO ASTRONOMY LA English DT Proceedings Paper CT Nuffield-Radio-Astronomy-Laboratories Conference - Sub-arcsecond Radio Astronomy CY JUL 20-24, 1992 CL UNIV MANCHESTER, MANCHESTER, ENGLAND SP NUFFIELD RADIO ASTRON LABS HO UNIV MANCHESTER C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 4 Z9 4 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1RP BN 0-521-43472-6 PY 1993 BP 150 EP 151 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BC51K UT WOS:A1993BC51K00049 ER PT B AU MEIER, DL AF MEIER, DL BE Davis, RJ Booth, RS TI MULTI-EPOCH 8.4-GHZ VLBI OBSERVATIONS OF THE NUCLEUS OF CENTAURUS-A SO SUB-ARCSECOND RADIO ASTRONOMY LA English DT Proceedings Paper CT Nuffield-Radio-Astronomy-Laboratories Conference - Sub-arcsecond Radio Astronomy CY JUL 20-24, 1992 CL UNIV MANCHESTER, MANCHESTER, ENGLAND SP NUFFIELD RADIO ASTRON LABS HO UNIV MANCHESTER C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 6 Z9 6 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1RP BN 0-521-43472-6 PY 1993 BP 201 EP 203 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BC51K UT WOS:A1993BC51K00067 ER PT B AU MURPHY, DW AF MURPHY, DW BE Davis, RJ Booth, RS TI 2.3-GHZ VLBI IMAGES OF SOUTHERN HEMISPHERE RADIO GALAXIES AND QUASARS SO SUB-ARCSECOND RADIO ASTRONOMY LA English DT Proceedings Paper CT Nuffield-Radio-Astronomy-Laboratories Conference - Sub-arcsecond Radio Astronomy CY JUL 20-24, 1992 CL UNIV MANCHESTER, MANCHESTER, ENGLAND SP NUFFIELD RADIO ASTRON LABS HO UNIV MANCHESTER C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 3 Z9 3 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1RP BN 0-521-43472-6 PY 1993 BP 243 EP 244 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BC51K UT WOS:A1993BC51K00085 ER PT B AU PRESTON, RA AF PRESTON, RA BE Davis, RJ Booth, RS TI THE SOUTHERN HEMISPHERE VLBI EXPERIMENT (SHEVE) SO SUB-ARCSECOND RADIO ASTRONOMY LA English DT Proceedings Paper CT Nuffield-Radio-Astronomy-Laboratories Conference - Sub-arcsecond Radio Astronomy CY JUL 20-24, 1992 CL UNIV MANCHESTER, MANCHESTER, ENGLAND SP NUFFIELD RADIO ASTRON LABS HO UNIV MANCHESTER C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 6 Z9 6 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1RP BN 0-521-43472-6 PY 1993 BP 428 EP 430 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BC51K UT WOS:A1993BC51K00146 ER PT B AU MEIER, DL MURPHY, DW PRESTON, RA AF MEIER, DL MURPHY, DW PRESTON, RA BE Davis, RJ Booth, RS TI PRELIMINARY SPACE VLBI REQUIREMENTS FOR OBSERVING TIME ON GROUND RADIO TELESCOPES SO SUB-ARCSECOND RADIO ASTRONOMY LA English DT Proceedings Paper CT Nuffield-Radio-Astronomy-Laboratories Conference - Sub-arcsecond Radio Astronomy CY JUL 20-24, 1992 CL UNIV MANCHESTER, MANCHESTER, ENGLAND SP NUFFIELD RADIO ASTRON LABS HO UNIV MANCHESTER C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 1 Z9 1 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1RP BN 0-521-43472-6 PY 1993 BP 437 EP 438 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BC51K UT WOS:A1993BC51K00149 ER PT B AU SOMER, RA PECOT, CE AF SOMER, RA PECOT, CE GP SAS USERS GRP INT TI A MAINFRAME MICROCOMPUTER PERSONNEL SALARY REVIEW INPUT AND ANALYSIS MANAGEMENT INFORMATION APPLICATION SO SUGI 18: PROCEEDINGS OF THE EIGHTEENTH ANNUAL SAS USERS GROUP INTERNATIONAL CONFERENCE LA English DT Proceedings Paper CT 18th Annual SAS Users Group International Conference (SUGI 18) CY MAY 09-12, 1993 CL NEW YORK, NY SP SAS USERS GRP INT DE MAINFRAME MICRO; HUMAN RESOURCE APPLICATIONS; PERSONNEL DATA ANALYSIS; COMPENSATION ANALYSIS; MIS; SAS/CLIPPER MIS APPLICATION C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAS INST INC PI CARY PA SAS CIRCLE, PO BOX 8000, CARY, NC 27511 BN 1-55544-550-0 PY 1993 BP 1506 EP 1515 PG 10 WC Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA BA72C UT WOS:A1993BA72C00249 ER PT S AU DAGUM, L AF DAGUM, L GP IEEE TI AUTOMATIC PARTITIONING OF UNSTRUCTURED GRIDS INTO CONNECTED COMPONENTS SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,AMES RES CTR,COMP SCI CORP,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 94 EP 101 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00010 ER PT S AU VANDERWIJNGAART, RF AF VANDERWIJNGAART, RF GP IEEE TI EFFICIENT IMPLEMENTATION OF A 3-DIMENSIONAL ADI METHOD ON THE IPSC/860 SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,AMES RES CTR,MCAT INST,MOFFETT FIELD,CA 94035. NR 0 TC 2 Z9 2 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 102 EP 111 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00011 ER PT S AU LEUTENEGGER, ST SUN, XH AF LEUTENEGGER, ST SUN, XH GP IEEE TI DISTRIBUTED COMPUTING FEASIBILITY IN A NON-DEDICATED HOMOGENEOUS DISTRIBUTED SYSTEM SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,LANGLEY RES CTR,INST COMP APPLICAT SCI & ENGN,HAMPTON,VA 23665. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 143 EP 152 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00015 ER PT S AU CHATTERJEE, S GILBERT, JR SCHREIBER, R AF CHATTERJEE, S GILBERT, JR SCHREIBER, R GP IEEE TI MOBILE AND REPLICATED ALIGNMENT OF ARRAYS IN DATA-PARALLEL PROGRAMS SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,AMES RES CTR,ADV COMP SCI RES INST,MOFFETT FIELD,CA 94035. NR 0 TC 3 Z9 3 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 420 EP 429 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00043 ER PT S AU BARNARD, ST POTHEN, A SIMON, HD AF BARNARD, ST POTHEN, A SIMON, HD GP IEEE TI A SPECTRAL ALGORITHM FOR ENVELOPE REDUCTION OF SPARSE MATRICES SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,AMES RES CTR,CRAY RES INC,MOFFETT FIELD,CA 94035. NR 0 TC 4 Z9 4 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 493 EP 502 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00051 ER PT S AU GRAFFUNDER, SK AF GRAFFUNDER, SK GP IEEE TI BARRIER-BREAKING PERFORMANCE FOR INDUSTRIAL-PROBLEMS ON THE CRAY-C916 SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,AMES RES CTR,CRAY RES INC,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 516 EP 519 PG 4 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00054 ER PT S AU BAILEY, DH AF BAILEY, DH GP IEEE TI RISC MICROPROCESSORS AND SCIENTIFIC COMPUTING SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 645 EP 654 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00069 ER PT S AU CHENG, DY AF CHENG, DY GP IEEE TI HETEROGENEOUS DISTRIBUTED COMPUTING - SUMMARY OF A MINISYMPOSIUM SO SUPERCOMPUTING '93, PROCEEDINGS SE SUPERCOMPUTING PROCEEDINGS LA English DT Proceedings Paper CT Supercomputing 93 Conference CY NOV 15-19, 1993 CL PORTLAND, OR SP IEEE, COMP SOC, TECH COMM SUPERCOMPUT APPL & COMP ARCHITECTURE, ASSOC COMP MACHINERY, SPECIAL INTEREST GRP ARCHITECTURE C1 NASA,AMES RES CTR,CSC,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1063-9535 BN 0-8186-4340-4 J9 SUPERCOMP PROC PY 1993 BP 762 EP 762 PG 1 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BA18A UT WOS:A1993BA18A00080 ER PT J AU LANGEL, RA AF LANGEL, RA TI THE USE OF LOW ALTITUDE SATELLITE DATA-BASES FOR MODELING OF CORE AND CRUSTAL FIELDS AND THE SEPARATION OF EXTERNAL AND INTERNAL FIELDS SO SURVEYS IN GEOPHYSICS LA English DT Review ID MAPPING ELECTRODYNAMIC FEATURES; HIGH-LATITUDE IONOSPHERE; INCOHERENT-SCATTER RADAR; MAGSAT VECTOR DATA; LOCALIZED OBSERVATIONS; MAGNETIC-ANOMALIES; DATA SET; SCALE; EARTH; REGION AB The near-Earth geomagnetic field is a complex combination of fields from a variety of sources within and external to the Earth. These fields have a complex characterization in space and time such that if the field were known at all times and positions external to the Earth's surface it would be possible to separate the measured field into its component parts except for the low degree field from the crust and the high degree field from the core. In practice the measurements come far short of such a space-time characterization. Because of this it is useful to keep in mind several principles when working with these data. These principles are: (1) know the enemy, i.e., understand as much as possible about all the sources, (2) don't expect a boy to do a man's job, i.e., recognize the limitations of the data, (3) use some common sense, and, (4) recognize personal prejudice. Examples are given from published and unpublished results to illustrate how these principles have been, and ought to be, applied. At the same time, suggestions are made as to how future analyses might proceed. These examples are drawn first of all from the way the main field and near-Earth magnetospheric fields are modeled, then from analyses of residuals from such models resulting from ionospheric and crustal fields. RP LANGEL, RA (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GEODYNAM BRANCH,GREENBELT,MD 20771, USA. NR 69 TC 18 Z9 20 U1 0 U2 2 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. PD JAN PY 1993 VL 14 IS 1 BP 31 EP & DI 10.1007/BF01044077 PG 0 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KK141 UT WOS:A1993KK14100002 ER PT B AU MESSINA, P STERLING, T AF MESSINA, P STERLING, T BE Messina, P Sterling, T TI SYSTEM SOFTWARE AND TOOLS FOR HIGH-PERFORMANCE COMPUTING ENVIRONMENTS SO SYSTEM SOFTWARE AND TOOLS FOR HIGH PERFORMANCE COMPUTING ENVIRONMENTS LA English DT Proceedings Paper CT Pasadena Workshop on System Software and Tools for High Performance Computing Environments CY APR 14-16, 1992 CL JET PROPULS LAB, PASADENA, CA SP NASA, ADV RES PROJECTS AGCY, US DOE, NATL SCI FDN, NATL INST STAND & TECHNOL, NOAA, NIH, US EPA, NATL SECUR AGCY HO JET PROPULS LAB C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 BN 0-89871-326-9 PY 1993 BP 1 EP 7 PG 7 WC Computer Science, Software Engineering SC Computer Science GA BZ45E UT WOS:A1993BZ45E00001 ER PT B AU MESSINA, P STERLING, T AF MESSINA, P STERLING, T BE Messina, P Sterling, T TI SUMMARY OF WORKING GROUP FINDINGS SO SYSTEM SOFTWARE AND TOOLS FOR HIGH PERFORMANCE COMPUTING ENVIRONMENTS LA English DT Proceedings Paper CT Pasadena Workshop on System Software and Tools for High Performance Computing Environments CY APR 14-16, 1992 CL JET PROPULS LAB, PASADENA, CA SP NASA, ADV RES PROJECTS AGCY, US DOE, NATL SCI FDN, NATL INST STAND & TECHNOL, NOAA, NIH, US EPA, NATL SECUR AGCY HO JET PROPULS LAB C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 BN 0-89871-326-9 PY 1993 BP 9 EP 24 PG 16 WC Computer Science, Software Engineering SC Computer Science GA BZ45E UT WOS:A1993BZ45E00002 ER PT B AU MESSINA, P STERLING, T AF MESSINA, P STERLING, T BE Messina, P Sterling, T TI ISSUES AND OBSERVATIONS SO SYSTEM SOFTWARE AND TOOLS FOR HIGH PERFORMANCE COMPUTING ENVIRONMENTS LA English DT Proceedings Paper CT Pasadena Workshop on System Software and Tools for High Performance Computing Environments CY APR 14-16, 1992 CL JET PROPULS LAB, PASADENA, CA SP NASA, ADV RES PROJECTS AGCY, US DOE, NATL SCI FDN, NATL INST STAND & TECHNOL, NOAA, NIH, US EPA, NATL SECUR AGCY HO JET PROPULS LAB C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 BN 0-89871-326-9 PY 1993 BP 115 EP 135 PG 21 WC Computer Science, Software Engineering SC Computer Science GA BZ45E UT WOS:A1993BZ45E00010 ER PT B AU MESSINA, P STERLING, T AF MESSINA, P STERLING, T BE Messina, P Sterling, T TI CONCLUSIONS AND IMPLICATIONS TO HPC SO SYSTEM SOFTWARE AND TOOLS FOR HIGH PERFORMANCE COMPUTING ENVIRONMENTS LA English DT Proceedings Paper CT Pasadena Workshop on System Software and Tools for High Performance Computing Environments CY APR 14-16, 1992 CL JET PROPULS LAB, PASADENA, CA SP NASA, ADV RES PROJECTS AGCY, US DOE, NATL SCI FDN, NATL INST STAND & TECHNOL, NOAA, NIH, US EPA, NATL SECUR AGCY HO JET PROPULS LAB C1 JET PROP LAB,PASADENA,CA 91109. RI novacescu, florica/B-4503-2011 OI novacescu, florica/0000-0001-5561-4956 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 BN 0-89871-326-9 PY 1993 BP 137 EP 149 PG 13 WC Computer Science, Software Engineering SC Computer Science GA BZ45E UT WOS:A1993BZ45E00011 ER PT B AU KIM, WS SCHENKER, PS BEJCZY, AK LEAKE, S OLLENDORF, S AF KIM, WS SCHENKER, PS BEJCZY, AK LEAKE, S OLLENDORF, S BE Kim, WS TI AN ADVANCED OPERATOR INTERFACE DESIGN WITH PREVIEW PREDICTIVE DISPLAYS FOR GROUND-CONTROLLED SPACE TELEROBOTIC SERVICING SO TELEMANIPULATOR TECHNOLOGY AND SPACE TELEROBOTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1993 SPIE Technical Conference on Telemanipulator Technology and Space Telerobotics CY SEP 07-09, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1322-4 J9 P SOC PHOTO-OPT INS PY 1993 VL 2057 BP 96 EP 107 DI 10.1117/12.164892 PG 12 WC Automation & Control Systems; Engineering, Aerospace; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74F UT WOS:A1993BZ74F00009 ER PT B AU PALJUG, ED SCHENKER, PS AF PALJUG, ED SCHENKER, PS BE Kim, WS TI ADVANCED TELEOPERATION CONTROLLER ARCHITECTURE SO TELEMANIPULATOR TECHNOLOGY AND SPACE TELEROBOTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1993 SPIE Technical Conference on Telemanipulator Technology and Space Telerobotics CY SEP 07-09, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1322-4 J9 P SOC PHOTO-OPT INS PY 1993 VL 2057 BP 239 EP 248 DI 10.1117/12.164905 PG 10 WC Automation & Control Systems; Engineering, Aerospace; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74F UT WOS:A1993BZ74F00022 ER PT B AU CHEUNG, E LEAKE, S AF CHEUNG, E LEAKE, S BE Kim, WS TI END-TO-END ROBOTIC MODULE CHANGEOUT PROCEDURE ON THE EXPLORER PLATFORM SPACECRAFT SO TELEMANIPULATOR TECHNOLOGY AND SPACE TELEROBOTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1993 SPIE Technical Conference on Telemanipulator Technology and Space Telerobotics CY SEP 07-09, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 NASA,GODDARD SPACE FLIGHT CTR,JACKSON & TULL,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1322-4 J9 P SOC PHOTO-OPT INS PY 1993 VL 2057 BP 292 EP 302 DI 10.1117/12.164910 PG 11 WC Automation & Control Systems; Engineering, Aerospace; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74F UT WOS:A1993BZ74F00027 ER PT B AU DINER, DB AF DINER, DB BE Kim, WS TI MONOCULAR TV VS STEREO TV FOR SOLAR MAXIMUM SATELLITE REPAIR SUBTASKS SO TELEMANIPULATOR TECHNOLOGY AND SPACE TELEROBOTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1993 SPIE Technical Conference on Telemanipulator Technology and Space Telerobotics CY SEP 07-09, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1322-4 J9 P SOC PHOTO-OPT INS PY 1993 VL 2057 BP 325 EP 336 DI 10.1117/12.164913 PG 12 WC Automation & Control Systems; Engineering, Aerospace; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74F UT WOS:A1993BZ74F00030 ER PT B AU ERICKSON, JD AUCOIN, PJ OSSORIO, PG AF ERICKSON, JD AUCOIN, PJ OSSORIO, PG BE Kim, WS TI INTEGRATED APPROACH FOR DELINEATING ROBOTIC CAPABILITIES NEEDED FOR FUTURE SPACE EXPLORATION TASKS SO TELEMANIPULATOR TECHNOLOGY AND SPACE TELEROBOTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1993 SPIE Technical Conference on Telemanipulator Technology and Space Telerobotics CY SEP 07-09, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1322-4 J9 P SOC PHOTO-OPT INS PY 1993 VL 2057 BP 370 EP 384 DI 10.1117/12.164917 PG 15 WC Automation & Control Systems; Engineering, Aerospace; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74F UT WOS:A1993BZ74F00034 ER PT B AU HAWKINS, S AF HAWKINS, S BE Kim, WS TI A REACTIVE NAVIGATIONAL CONTROLLER FOR AUTONOMOUS MOBILE ROBOTS SO TELEMANIPULATOR TECHNOLOGY AND SPACE TELEROBOTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1993 SPIE Technical Conference on Telemanipulator Technology and Space Telerobotics CY SEP 07-09, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 NASA,LYNDON B JOHNSON SPACE CTR,DIV AUTOMAT & ROBOT,HOUSTON,TX 77058. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1322-4 J9 P SOC PHOTO-OPT INS PY 1993 VL 2057 BP 409 EP 417 DI 10.1117/12.164920 PG 9 WC Automation & Control Systems; Engineering, Aerospace; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74F UT WOS:A1993BZ74F00037 ER PT B AU KIZHNER, S AF KIZHNER, S BE Kim, WS TI ON CAPACIFLECTOR SENSOR IMAGING AND RANGING APPLICATIONS FOR ROBOT CONTROL SO TELEMANIPULATOR TECHNOLOGY AND SPACE TELEROBOTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1993 SPIE Technical Conference on Telemanipulator Technology and Space Telerobotics CY SEP 07-09, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 NASA,GODDARD SPACE FLIGHT CTR,ROBOT BRANCH,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1322-4 J9 P SOC PHOTO-OPT INS PY 1993 VL 2057 BP 443 EP 453 DI 10.1117/12.164923 PG 11 WC Automation & Control Systems; Engineering, Aerospace; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74F UT WOS:A1993BZ74F00040 ER PT B AU CHENG, DY AF CHENG, DY BE Yuan, BZ TI PARALLEL PROGRAMMING AS NASA/NAS SO TENCON '93: 1993 IEEE REGION 10 CONFERENCE ON COMPUTER, COMMUNICATION, CONTROL AND POWER ENGINEERING, VOL 1 LA English DT Proceedings Paper CT TENCON 93 - 1993 IEEE Region 10 Conference on Computer, Communication, Control and Power Engineering CY OCT 19-21, 1993 CL BEIJING, PEOPLES R CHINA SP IEEE, BEIJING SECT, NO JIAOTONG UNIV C1 NASA,AMES RES CTR,CSC,MOFFETT FIELD,CA 94305. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT ACADEMIC PUBL PI BEIJING PA 137 CHAONEI DAJIE, BEIJING 100010, PEOPLES R CHINA BN 7-80003-285-X PY 1993 BP 103 EP 105 PG 3 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BA40Y UT WOS:A1993BA40Y00025 ER PT S AU FICHTEL, CE AF FICHTEL, CE BE Akerlof, CW Srednicki, MA TI RECENT RESULTS FROM THE COMPTON GAMMA-RAY OBSERVATORY SO TEXAS/PASCOS 92 : RELATIVISTIC ASTROPHYSICS AND PARTICLE COSMOLOGY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Proceedings Paper CT 16TH TEXAS SYMP ON RELATIVISTIC ASTROPHYSICS / 3RD INTERNATIONAL SYMP ON PARTICLES, STRINGS, AND COSMOLOGY CY DEC 13-18, 1992 CL BERKELEY, CA SP NEW YORK ACAD SCI, CTR PARTICLE ASTROPHYS, US DOE, PERMILAB, LAWRENCE BERKELEY LAB, LAWRENCE LIVERMORE NATL LAB, NASA, NATL SCI FDN, SSC, STANFORD LINEAR ACCELERATOR RP FICHTEL, CE (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,GREENBELT,MD 20771, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA NEW YORK SN 0077-8923 BN 0-89766-805-7 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1993 VL 688 BP 136 EP 147 DI 10.1111/j.1749-6632.1993.tb43892.x PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BY69T UT WOS:A1993BY69T00012 PM 26469417 ER PT S AU MUSHOTZKY, R AF MUSHOTZKY, R BE Akerlof, CW Srednicki, MA TI IMPLICATIONS OF RECENT CLUSTER OBSERVATIONS FOR COSMOLOGY SO TEXAS/PASCOS 92 : RELATIVISTIC ASTROPHYSICS AND PARTICLE COSMOLOGY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Proceedings Paper CT 16TH TEXAS SYMP ON RELATIVISTIC ASTROPHYSICS / 3RD INTERNATIONAL SYMP ON PARTICLES, STRINGS, AND COSMOLOGY CY DEC 13-18, 1992 CL BERKELEY, CA SP NEW YORK ACAD SCI, CTR PARTICLE ASTROPHYS, US DOE, PERMILAB, LAWRENCE BERKELEY LAB, LAWRENCE LIVERMORE NATL LAB, NASA, NATL SCI FDN, SSC, STANFORD LINEAR ACCELERATOR RP MUSHOTZKY, R (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,GREENBELT,MD 20771, USA. NR 0 TC 12 Z9 12 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA NEW YORK SN 0077-8923 BN 0-89766-805-7 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1993 VL 688 BP 184 EP 194 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BY69T UT WOS:A1993BY69T00015 ER PT S AU HARDING, AK AF HARDING, AK BE Akerlof, CW Srednicki, MA TI GAMMA-RAY EMISSION FROM PULSARS SO TEXAS/PASCOS 92 : RELATIVISTIC ASTROPHYSICS AND PARTICLE COSMOLOGY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Proceedings Paper CT 16TH TEXAS SYMP ON RELATIVISTIC ASTROPHYSICS / 3RD INTERNATIONAL SYMP ON PARTICLES, STRINGS, AND COSMOLOGY CY DEC 13-18, 1992 CL BERKELEY, CA SP NEW YORK ACAD SCI, CTR PARTICLE ASTROPHYS, US DOE, PERMILAB, LAWRENCE BERKELEY LAB, LAWRENCE LIVERMORE NATL LAB, NASA, NATL SCI FDN, SSC, STANFORD LINEAR ACCELERATOR RP HARDING, AK (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,GREENBELT,MD 20771, USA. RI Harding, Alice/D-3160-2012 NR 0 TC 2 Z9 2 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA NEW YORK SN 0077-8923 BN 0-89766-805-7 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1993 VL 688 BP 573 EP 580 DI 10.1111/j.1749-6632.1993.tb43939.x PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BY69T UT WOS:A1993BY69T00059 PM 26469464 ER PT S AU OZERNOY, LM AF OZERNOY, LM BE Akerlof, CW Srednicki, MA TI THE GALACTIC-CENTER PUTATIVE BLACK-HOLE - RECENT MASS EVALUATIONS SO TEXAS/PASCOS 92 : RELATIVISTIC ASTROPHYSICS AND PARTICLE COSMOLOGY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Proceedings Paper CT 16TH TEXAS SYMP ON RELATIVISTIC ASTROPHYSICS / 3RD INTERNATIONAL SYMP ON PARTICLES, STRINGS, AND COSMOLOGY CY DEC 13-18, 1992 CL BERKELEY, CA SP NEW YORK ACAD SCI, CTR PARTICLE ASTROPHYS, US DOE, PERMILAB, LAWRENCE BERKELEY LAB, LAWRENCE LIVERMORE NATL LAB, NASA, NATL SCI FDN, SSC, STANFORD LINEAR ACCELERATOR RP OZERNOY, LM (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GSFC,USRA,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771, USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA NEW YORK SN 0077-8923 BN 0-89766-805-7 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1993 VL 688 BP 596 EP 597 DI 10.1111/j.1749-6632.1993.tb43942.x PG 2 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BY69T UT WOS:A1993BY69T00062 PM 26469467 ER PT S AU STEBBINS, A AF STEBBINS, A BE Akerlof, CW Srednicki, MA TI ON THE MEANING OF DELTA-T/T SO TEXAS/PASCOS 92 : RELATIVISTIC ASTROPHYSICS AND PARTICLE COSMOLOGY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Proceedings Paper CT 16TH TEXAS SYMP ON RELATIVISTIC ASTROPHYSICS / 3RD INTERNATIONAL SYMP ON PARTICLES, STRINGS, AND COSMOLOGY CY DEC 13-18, 1992 CL BERKELEY, CA SP NEW YORK ACAD SCI, CTR PARTICLE ASTROPHYS, US DOE, PERMILAB, LAWRENCE BERKELEY LAB, LAWRENCE LIVERMORE NATL LAB, NASA, NATL SCI FDN, SSC, STANFORD LINEAR ACCELERATOR RP STEBBINS, A (reprint author), NASA,FERMILAB ASTROPHYS CTR,FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA NEW YORK SN 0077-8923 BN 0-89766-805-7 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1993 VL 688 BP 824 EP 826 DI 10.1111/j.1749-6632.1993.tb43982.x PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BY69T UT WOS:A1993BY69T00102 PM 26469507 ER PT S AU KASHLINSKY, A AF KASHLINSKY, A BE Akerlof, CW Srednicki, MA TI LARGE-SCALE DATA, MICROWAVE BACKGROUND AND INFLATION SO TEXAS/PASCOS 92 : RELATIVISTIC ASTROPHYSICS AND PARTICLE COSMOLOGY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Proceedings Paper CT 16TH TEXAS SYMP ON RELATIVISTIC ASTROPHYSICS / 3RD INTERNATIONAL SYMP ON PARTICLES, STRINGS, AND COSMOLOGY CY DEC 13-18, 1992 CL BERKELEY, CA SP NEW YORK ACAD SCI, CTR PARTICLE ASTROPHYS, US DOE, PERMILAB, LAWRENCE BERKELEY LAB, LAWRENCE LIVERMORE NATL LAB, NASA, NATL SCI FDN, SSC, STANFORD LINEAR ACCELERATOR RP KASHLINSKY, A (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 685,GREENBELT,MD 20771, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA NEW YORK SN 0077-8923 BN 0-89766-805-7 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1993 VL 688 BP 830 EP 832 DI 10.1111/j.1749-6632.1993.tb43984.x PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BY69T UT WOS:A1993BY69T00104 PM 26469509 ER PT J AU RENDELL, AP LEE, TJ KOMORNICKI, A WILSON, S AF RENDELL, AP LEE, TJ KOMORNICKI, A WILSON, S TI EVALUATION OF THE CONTRIBUTION FROM TRIPLY EXCITED INTERMEDIATES TO THE 4TH-ORDER PERTURBATION-THEORY ENERGY ON INTEL DISTRIBUTED MEMORY SUPERCOMPUTERS SO THEORETICA CHIMICA ACTA LA English DT Article; Proceedings Paper CT WORKSHOP ON PARALLEL COMPUTING IN CHEMICAL PHYSICS CY JUL 17-19, 1991 CL ARGONNE NATL LAB, ARGONNE, IL SP ARGONNE NATL LAB, PHYS RES THEORY INST DICTIONARY FUND, BATTLE PACIFIC NW LABS HO ARGONNE NATL LAB DE 4TH-ORDER TRIPLE EXCITATION ENERGY; MANY-BODY PERTURBATION THEORY; INTEL DISTRIBUTED MEMORY PARALLEL COMPUTERS ID FULL CCSDT MODEL; MOLECULAR ELECTRONIC-STRUCTURE; SUBSTITUTIONS; EXCITATIONS; EXPANSION; INCLUDE; TERMS; ATOMS AB Three previously reported algorithms for the evaluation of the fourth-order triple excitation energy component in many-body perturbation theory have been compared. Their implementation on current Intel distributed memory parallel computers has been investigated. None of the algorithms, which were developed for shared memory computer architectures, performed well since they lead to prohibitive IO demands. A new algorithm suitable for distributed memory machines is suggested and its implementation on two Intel i860 super-computers is described. A high level of parallelism is obtained. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. POLYATOM RES INST,MT VIEW,CA 94043. SERC,RUTHERFORD APPLETON LAB,CHILTON OX11 0QX,OXON,ENGLAND. RP RENDELL, AP (reprint author), SERC,DARESBURY LAB,WARRINGTON WA4 4AD,CHESHIRE,ENGLAND. RI Rendell, Alistair/A-4883-2008; Lee, Timothy/K-2838-2012 OI Rendell, Alistair/0000-0002-9445-0146; NR 44 TC 18 Z9 18 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0040-5744 J9 THEOR CHIM ACTA JI Theor. Chim. Acta PD JAN PY 1993 VL 84 IS 4-5 BP 271 EP 287 DI 10.1007/BF01113267 PG 17 WC Chemistry, Physical SC Chemistry GA KJ022 UT WOS:A1993KJ02200003 ER PT B AU Chehbouni, A Njoku, EG Lhomme, JP Kerr, YH AF Chehbouni, A Njoku, EG Lhomme, JP Kerr, YH BE Carlson, T Taconet, O Vidal, A Moran, S Gillies, R TI Aggregation techniques for estimating hydrologic flux controlling parameters: Application to remotely sensed surface temperature SO THERMAL REMOTE SENSING OF THE ENERGY AND WATER BALANCE OVER VEGETATION IN CONJUNCTION WITH OTHER SENSORS LA English DT Proceedings Paper CT Workshop on Thermal Remote Sensing of the Energy and Water Balance Over Vegetation in Conjunction with Other Sensors CY SEP 20-24, 1993 CL LA LONDE LES MAURES, FRANCE SP Penn State Univ, Ctr Etude Environm Terrestre & Planetaires, CEMAGREF ENGREF C1 CALTECH,JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CEMAGREF EDITIONS PI ANTHONY CEDEX PA BP 22, 92162 ANTHONY CEDEX, FRANCE BN 2-85362-371-8 PY 1993 BP 129 EP 131 PG 3 WC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources SC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources GA BE49V UT WOS:A1993BE49V00015 ER PT B AU Jasinski, MF AF Jasinski, MF BE Carlson, T Taconet, O Vidal, A Moran, S Gillies, R TI Physically based estimation of subpixel vegetation cover using satellite multispectral imagery SO THERMAL REMOTE SENSING OF THE ENERGY AND WATER BALANCE OVER VEGETATION IN CONJUNCTION WITH OTHER SENSORS LA English DT Proceedings Paper CT Workshop on Thermal Remote Sensing of the Energy and Water Balance Over Vegetation in Conjunction with Other Sensors CY SEP 20-24, 1993 CL LA LONDE LES MAURES, FRANCE SP Penn State Univ, Ctr Etude Environm Terrestre & Planetaires, CEMAGREF ENGREF C1 NASA,GODDARD SPACE FLIGHT CTR,HYDROL SCI BRANCH,GREENBELT,MD 20771. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CEMAGREF EDITIONS PI ANTHONY CEDEX PA BP 22, 92162 ANTHONY CEDEX, FRANCE BN 2-85362-371-8 PY 1993 BP 177 EP 180 PG 4 WC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources SC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources GA BE49V UT WOS:A1993BE49V00022 ER PT B AU Luvall, JC James, K Schneider, E AF Luvall, JC James, K Schneider, E BE Carlson, T Taconet, O Vidal, A Moran, S Gillies, R TI Thermal remote sensing in landscape ecology: A powerful tool in the characterization of landscapes on a functional basis SO THERMAL REMOTE SENSING OF THE ENERGY AND WATER BALANCE OVER VEGETATION IN CONJUNCTION WITH OTHER SENSORS LA English DT Proceedings Paper CT Workshop on Thermal Remote Sensing of the Energy and Water Balance Over Vegetation in Conjunction with Other Sensors CY SEP 20-24, 1993 CL LA LONDE LES MAURES, FRANCE SP Penn State Univ, Ctr Etude Environm Terrestre & Planetaires, CEMAGREF ENGREF C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,HUNTSVILLE,AL 35812. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CEMAGREF EDITIONS PI ANTHONY CEDEX PA BP 22, 92162 ANTHONY CEDEX, FRANCE BN 2-85362-371-8 PY 1993 BP 201 EP 204 PG 4 WC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources SC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources GA BE49V UT WOS:A1993BE49V00028 ER PT B AU Kahle, AB AF Kahle, AB BE Carlson, T Taconet, O Vidal, A Moran, S Gillies, R TI ASTER, a new spaceborne instrument which will contribute to thermal remote sensing of the energy and water balance over land surfaces SO THERMAL REMOTE SENSING OF THE ENERGY AND WATER BALANCE OVER VEGETATION IN CONJUNCTION WITH OTHER SENSORS LA English DT Proceedings Paper CT Workshop on Thermal Remote Sensing of the Energy and Water Balance Over Vegetation in Conjunction with Other Sensors CY SEP 20-24, 1993 CL LA LONDE LES MAURES, FRANCE SP Penn State Univ, Ctr Etude Environm Terrestre & Planetaires, CEMAGREF ENGREF C1 CALTECH,JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CEMAGREF EDITIONS PI ANTHONY CEDEX PA BP 22, 92162 ANTHONY CEDEX, FRANCE BN 2-85362-371-8 PY 1993 BP 213 EP 215 PG 3 WC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources SC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources GA BE49V UT WOS:A1993BE49V00031 ER PT B AU Quattrochi, DA AF Quattrochi, DA BE Carlson, T Taconet, O Vidal, A Moran, S Gillies, R TI Use of thermal infrared multispectral scanner (TIMS) data for analysis of urban landscape and vegetation responses SO THERMAL REMOTE SENSING OF THE ENERGY AND WATER BALANCE OVER VEGETATION IN CONJUNCTION WITH OTHER SENSORS LA English DT Proceedings Paper CT Workshop on Thermal Remote Sensing of the Energy and Water Balance Over Vegetation in Conjunction with Other Sensors CY SEP 20-24, 1993 CL LA LONDE LES MAURES, FRANCE SP Penn State Univ, Ctr Etude Environm Terrestre & Planetaires, CEMAGREF ENGREF C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,SPACE SCI LAB,HUNTSVILLE,AL 35812. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CEMAGREF EDITIONS PI ANTHONY CEDEX PA BP 22, 92162 ANTHONY CEDEX, FRANCE BN 2-85362-371-8 PY 1993 BP 221 EP 226 PG 6 WC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources SC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources GA BE49V UT WOS:A1993BE49V00033 ER PT B AU Luvall, JC AF Luvall, JC BE Carlson, T Taconet, O Vidal, A Moran, S Gillies, R TI The use of an aircraft based thermal infrared multispectral scanner (TIMS) data to measure surface energy budgets on a landscape scale SO THERMAL REMOTE SENSING OF THE ENERGY AND WATER BALANCE OVER VEGETATION IN CONJUNCTION WITH OTHER SENSORS LA English DT Proceedings Paper CT Workshop on Thermal Remote Sensing of the Energy and Water Balance Over Vegetation in Conjunction with Other Sensors CY SEP 20-24, 1993 CL LA LONDE LES MAURES, FRANCE SP Penn State Univ, Ctr Etude Environm Terrestre & Planetaires, CEMAGREF ENGREF C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,EARTH SCI & APPLICAT DIV,HUNTSVILLE,AL 35812. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CEMAGREF EDITIONS PI ANTHONY CEDEX PA BP 22, 92162 ANTHONY CEDEX, FRANCE BN 2-85362-371-8 PY 1993 BP 275 EP 279 PG 5 WC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources SC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources GA BE49V UT WOS:A1993BE49V00043 ER PT B AU Quattrochi, DA Astling, EG AF Quattrochi, DA Astling, EG BE Carlson, T Taconet, O Vidal, A Moran, S Gillies, R TI TIMS data for measurement of thermal responses over mountain desert terrain SO THERMAL REMOTE SENSING OF THE ENERGY AND WATER BALANCE OVER VEGETATION IN CONJUNCTION WITH OTHER SENSORS LA English DT Proceedings Paper CT Workshop on Thermal Remote Sensing of the Energy and Water Balance Over Vegetation in Conjunction with Other Sensors CY SEP 20-24, 1993 CL LA LONDE LES MAURES, FRANCE SP Penn State Univ, Ctr Etude Environm Terrestre & Planetaires, CEMAGREF ENGREF C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,SPACE SCI LAB,NASA,HUNTSVILLE,AL 35812. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CEMAGREF EDITIONS PI ANTHONY CEDEX PA BP 22, 92162 ANTHONY CEDEX, FRANCE BN 2-85362-371-8 PY 1993 BP 317 EP 322 PG 6 WC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources SC Meteorology & Atmospheric Sciences; Remote Sensing; Water Resources GA BE49V UT WOS:A1993BE49V00051 ER PT B AU CHEN, PS SANDERS, JH ZIMMERMAN, FR LIAW, YK AF CHEN, PS SANDERS, JH ZIMMERMAN, FR LIAW, YK BE Berndt, CC Bernecki, TF TI MECHANICAL-PROPERTIES AND MICROSTRUCTURE OF VACUUM PLASMA-SPRAYED NARLOY-Z SO THERMAL SPRAY COATINGS: RESEARCH, DESIGN AND APPLICATIONS LA English DT Proceedings Paper CT 5th National Thermal Spray Conference and Exposition on Thermal Spray Technology: Growing to Serve Industry in Surface Protection and Materials Processing (NTSC 93) CY JUN 07-11, 1993 CL ANAHEIM, CA SP ASM INT, AMER WELDING SOC, DEUT VERBAND SCHWEISSTECH E V, JAPAN THERMAL SPRAYING SOC, HIGH TEMP SOC JAPAN, INT THERMAL SPRAY ASSOC C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,HUNTSVILLE,AL 35812. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASM INTERNATIONAL PI MATERIALS PARK PA 9503 KINSMAN RD, MATERIALS PARK, OH 44073 BN 0-87170-470-6 PY 1993 BP 549 EP 553 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BZ93M UT WOS:A1993BZ93M00086 ER PT B AU LIM, SG BREWE, DE HANDSCHUH, RF AF LIM, SG BREWE, DE HANDSCHUH, RF BE Dowson, D Taylor, CM Childs, THC Godet, M Dalmaz, G TI A TRANSIENT ELASTOHYDRODYNAMIC LUBRICATION ANALYSIS FOR SPIRAL BEVEL GEARS SO THIN FILMS IN TRIBOLOGY SE TRIBOLOGY SERIES LA English DT Proceedings Paper CT 19th Leeds-Lyon Symposium on Tribology: Thin Films in Tribology CY SEP 08-11, 1992 CL UNIV LEEDS, INST TRIBOL, LEEDS, ENGLAND HO UNIV LEEDS, INST TRIBOL C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE PUBL B V PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-89789-5 J9 TRIBOLOGY S PY 1993 VL 25 BP 157 EP 168 DI 10.1016/S0167-8922(08)70372-9 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BB04E UT WOS:A1993BB04E00015 ER PT S AU LOWRY, LE TAI, BH MATTILA, J WALSH, LH AF LOWRY, LE TAI, BH MATTILA, J WALSH, LH BE Townsend, PH Weihs, TP Sanchez, JE Borgesen, P TI MECHANICAL-STRESS EFFECTS ON ELECTROMIGRATION VOIDING IN A MEANDERING TEST STRIPE SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES IV SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films: Stresses and Mechanical Properties IV, at the 1993 Spring Meeting of the Materials-Research-Society CY APR 12-16, 1993 CL SAN FRANCISCO, CA SP MAT RES SOC, DOW CHEM CO, ADV MICRO DEVICES, LAWRENCE LIVERMORE NATL LAB, NANO INSTRUMENTS INC, QUAD GRP, TENCOR INSTRUMENTS, INDUSTRY CORNELL UNIV, ALLIANCE ELECTR PACKAGE C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOC PI PITTSBURGH PA 9800 MCKNIGHT RD, SUITE 327, PITTSBURGH, PA 15237 SN 0272-9172 BN 1-55899-204-9 J9 MATER RES SOC SYMP P PY 1993 VL 308 BP 273 EP 278 DI 10.1557/PROC-308-273 PG 6 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied SC Materials Science; Mechanics; Physics GA BZ55E UT WOS:A1993BZ55E00041 ER PT B AU GARYANTES, M GRIMM, M WILCK, H AF GARYANTES, M GRIMM, M WILCK, H BE Shostak, GS TI A WIDE-BAND, HIGH-RESOLUTION SPECTRUM ANALYZER SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 61 EP 64 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00008 ER PT B AU OLIVER, BM AF OLIVER, BM BE Shostak, GS TI SYMMETRY IN SETI SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. 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 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 67 EP 72 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00009 ER PT B AU CULLERS, DK AF CULLERS, DK BE Shostak, GS TI A NEW METHOD FOR DETERMINING THE MERITS OF SETI SEARCH STRATEGIES SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 75 EP 86 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00010 ER PT B AU ZIMMERMAN, GA GULKIS, S AF ZIMMERMAN, GA GULKIS, S BE Shostak, GS TI POLYPHASE DFT SPECTRUM ANALYSIS FOR THE SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE SKY SURVEY SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 119 EP 127 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00013 ER PT B AU OLSEN, ET JACKSON, EB GULKIS, S AF OLSEN, ET JACKSON, EB GULKIS, S BE Shostak, GS TI SETI SITE SURVEYS OF RFI IN THE BAND 1.0-GHZ-]10.4-GHZ SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 313 EP 321 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00029 ER PT B AU KLEIN, MJ BURNS, DJ FOSTER, CF GARYANTES, MF GULKIS, S LEVIN, SM OLSEN, ET WILCK, HC ZIMMERMAN, GA AF KLEIN, MJ BURNS, DJ FOSTER, CF GARYANTES, MF GULKIS, S LEVIN, SM OLSEN, ET WILCK, HC ZIMMERMAN, GA BE Shostak, GS TI THE NASA SETI MICROWAVE OBSERVING PROJECT SKY SURVEY SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 JET PROP LAB,PASADENA,CA 91109. 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 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 335 EP 347 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00031 ER PT B AU LEVIN, S ASMAR, P BURNS, D FOSTER, C GARYANTES, M GOSLINE, R GULKIS, S KLEIN, M OLSEN, ET WILCK, H ZIMMERMAN, G AF LEVIN, S ASMAR, P BURNS, D FOSTER, C GARYANTES, M GOSLINE, R GULKIS, S KLEIN, M OLSEN, ET WILCK, H ZIMMERMAN, G BE Shostak, GS TI PRELIMINARY TEST DATA FROM THE SETI MICROWAVE OBSERVING PROJECT SKY SURVEY PROTOTYPE SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 349 EP 355 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00032 ER PT B AU BILLINGHAM, J AF BILLINGHAM, J BE Shostak, GS TI SETI POSTDETECTION PROTOCOLS - WHAT DO YOU DO AFTER DETECTING A SIGNAL SO THIRD DECENNIAL US-USSR CONFERENCE ON SETI SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 3rd Decennial US-USSR Conference on SETI CY AUG 05-09, 1991 CL UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA SP UNIV CALIF SANTA CRUZ, SETI INST HO UNIV CALIF SANTA CRUZ C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. 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 BN 0-937707-66-X J9 ASTR SOC P PY 1993 VL 47 BP 417 EP 424 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BZ94V UT WOS:A1993BZ94V00039 ER PT B AU WALLACE, TA WIEDEMANN, KE CLARK, RK AF WALLACE, TA WIEDEMANN, KE CLARK, RK BE Froes, FH Caplan, IL TI OXIDATION CHARACTERISTICS OF BETA-21S IN AIR IN THE TEMPERATURE-RANGE 600 TO 800-DEGREES-C SO TITANIUM '92: SCIENCE AND TECHNOLOGY, VOLS 1-3 LA English DT Proceedings Paper CT Symposium on Titanium: Science and technology, at the 7th World Titanium Conference CY JUN 29-JUL 02, 1992 CL SAN DIEGO, CA SP MINERALS MET & MAT SOC, STRUCT MET DIV, TITANIUM COMM C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23665. NR 0 TC 2 Z9 2 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 BN 0-87339-222-1 PY 1993 BP 2177 EP 2184 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA BB20G UT WOS:A1993BB20G00265 ER PT B AU LEE, HS CHAI, JC PATANKAR, SV AF LEE, HS CHAI, JC PATANKAR, SV BE Lee, JS Chung, SH Kim, KH TI RECENT DEVELOPMENTS IN THE SOLUTION OF RADIATION HEAT-TRANSFER USING THE DISCRETE ORDINATES METHOD SO TRANSPORT PHENOMENA IN THERMAL ENGINEERING, VOLS 1 AND 2 LA English DT Proceedings Paper CT 6th International Symposium on Transport Phenomena in Thermal Engineering (ISTP-VI) CY MAY 09-13, 1993 CL SEOUL, SOUTH KOREA SP PACIFIC CTR THERMAL FLUIDS ENGN C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. RI Chai, John/A-3764-2010 NR 0 TC 1 Z9 1 U1 0 U2 0 PU BEGELL HOUSE, INC PI NEW YORK PA 79 MADISON AVE, SUITE 1106, NEW YORK, NY 10016 BN 1-56700-015-0 PY 1993 BP 203 EP 208 PG 6 WC Thermodynamics; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Engineering GA BA70Z UT WOS:A1993BA70Z00030 ER PT B AU SLATER, H OWENS, J AF SLATER, H OWENS, J BE Roehrenbeck, PW TI APPLIED IMAGING FOR SPACE EXPERIMENTS AT NASA LEWIS-RESEARCH-CENTER SO ULTRAHIGH- AND HIGH-SPEED PHOTOGRAPHY, VIDEOGRAPHY, AND PHOTONICS '93 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrahigh-Speed and High-Speed Photography, Videography, and Photonics 1993 CY JUL 13-14, 1993 CL SAN DIEGO, CA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1251-1 J9 P SOC PHOTO-OPT INS PY 1993 VL 2002 BP 58 EP 78 DI 10.1117/12.161370 PG 21 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BZ81G UT WOS:A1993BZ81G00006 ER PT J AU KLINE, RA CRUSE, G STRIZ, AG MADARAS, EI AF KLINE, RA CRUSE, G STRIZ, AG MADARAS, EI TI INTEGRATING NDE-DERIVED ENGINEERING PROPERTIES WITH FINITE-ELEMENT ANALYSIS FOR STRUCTURAL COMPOSITE-MATERIALS SO ULTRASONICS LA English DT Article DE FINITE ELEMENT ANALYSIS; QUANTITATIVE NDE; CARBON CARBON COMPOSITES AB In this work, the use of ultrasonic property measurements as the basis for finite element analysis of full-scale composite components is presented. The approach utilizes multiple velocity measurements at oblique angles of incidence and quantitative analysis of radiographic images for the local determination of each of the nine orthotropic moduli in a given carbon-carbon composite. These values were then used as input into a finite element code (NASTRAN) to analyse the response of the material to load; here diametric compression. The predicted response was then compared with strain gauge results at several locations in the part to validate the approach. C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP KLINE, RA (reprint author), UNIV OKLAHOMA,NORMAN,OK 73019, USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0041-624X J9 ULTRASONICS JI Ultrasonics PY 1993 VL 31 IS 1 BP 53 EP 59 DI 10.1016/0041-624X(93)90033-V PG 7 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA KG198 UT WOS:A1993KG19800007 ER PT B AU MADARAS, EI BRIDAL, SL HOLLAND, MR HANDLEY, SM MILLER, JG AF MADARAS, EI BRIDAL, SL HOLLAND, MR HANDLEY, SM MILLER, JG GP ULTRASONICS TI A METHOD FOR THE COMPENSATION OF THE EFFECTS OF SURFACE CLOTH IMPRESSIONS ON POLAR BACKSCATTER APPLIED TO POROUS EPOXY AND BIAXIAL GRAPHITE-EPOXY COMPOSITES SO ULTRASONICS INTERNATIONAL 93 - CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Ultrasonics International Conference CY JUL 06-08, 1993 CL VIENNA, AUSTRIA SP ULTRASONICS DE POLAR BACKSCATTER; INTERFACE IMPERFECTIONS; POROSITY C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23681. NR 0 TC 0 Z9 0 U1 0 U2 2 PU BUTTERWORTH-HEINEMANN PI OXFORD PA LINACRE HOUSE, JORDAN HILL, OXFORD, OXON, ENGLAND OX2 8DP BN 0-750618-77-9 PY 1993 BP 823 EP 826 PG 4 WC Acoustics SC Acoustics GA BA27D UT WOS:A1993BA27D00198 ER PT J AU NERGER, JL PIANTANIDA, TP LARIMER, J AF NERGER, JL PIANTANIDA, TP LARIMER, J TI COLOR APPEARANCE OF FILLED-IN BACKGROUNDS AFFECTS HUE CANCELLATION, BUT NOT DETECTION THRESHOLDS SO VISION RESEARCH LA English DT Article DE FILLING IN; STABILIZED RETINAL IMAGES; HUE CANCELLATION; DISCOUNTING THE BACKGROUND; CHROMATIC ADAPTATION ID TEMPORAL-MODULATION SENSITIVITY; CHROMATIC ADAPTATION; BLUE MECHANISM AB A long-wavelength background can affect the appearance of an increment of light superimposed upon it in two ways. It can change the visual system's sensitivity to the increment, and it can change the appearance of the increment by directly adding redness to it. Through selective retinal-image stabilization, we evoked the filling-in phenomenon to change the appearance of 640- and 575-nm backgrounds. Either of these backgrounds could be made to appear red or yellow, depending upon whether it was viewed under stabilized or unstabilized conditions. When the appearance of the 640-nm background was altered by filling-in to appear less red, test probes superimposed upon it required less 540-nm component to achieve an equilibrium hue. Increment thresholds measured on the 640- and 575-nm backgrounds, however, did not change with the appearance of the backgrounds. C1 SRI INT,CTR SENSORY SCI & TECHNOL,MENLO PK,CA 94025. NASA,AMES RES CTR,COMPUTAT HUMAN ENGN RES BRANCH,MOFFETT FIELD,CA 94035. RP NERGER, JL (reprint author), COLORADO STATE UNIV,DEPT PSYCHOL,FT COLLINS,CO 80523, USA. FU NEI NIH HHS [EY07014] NR 21 TC 11 Z9 11 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0042-6989 J9 VISION RES JI Vision Res. PD JAN PY 1993 VL 33 IS 2 BP 165 EP 172 DI 10.1016/0042-6989(93)90155-P PG 8 WC Neurosciences; Ophthalmology SC Neurosciences & Neurology; Ophthalmology GA KG753 UT WOS:A1993KG75300003 PM 8447090 ER PT B AU LEE, S YI, C AF LEE, S YI, C BE Breidenthal, SS Desrochers, AA TI FORCE-BASED REASONING IN ASSEMBLY PLANNING SO VISION, SENSORS, AND CONTROL FOR AUTOMATED MANUFACTURING SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Vision, Sensors, and Control for Automated Manufacturing Systems CY SEP 09-10, 1993 CL BOSTON, MA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS, AUTOMATED IMAGING ASSOC, CARNEGIE MELLON UNIV, CTR EXCELLENCE OPT DATA PROC, UNIV CONNECTICUT, ADV TECHNOL CTR PRECIS MFG, INT SOC PHOTOGRAMMETRY & REMOTE SENSING C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1328-3 J9 P SOC PHOTO-OPT INS PY 1993 VL 2063 BP 97 EP 108 DI 10.1117/12.164958 PG 12 WC Automation & Control Systems; Engineering, Manufacturing; Optics SC Automation & Control Systems; Engineering; Optics GA BZ74L UT WOS:A1993BZ74L00010 ER PT B AU LANE, DA AF LANE, DA BE Nielson, GM Bergeron, D TI VISUALIZATION OF TIME-DEPENDENT FLOW-FIELDS SO VISUALIZATION 93, PROCEEDINGS LA English DT Proceedings Paper CT Visualization 93, the 4th Annual IEEE Conference on Visualization CY OCT 25-29, 1993 CL SAN JOSE, CA SP IEEE, COMP SOC, TECH COMM COMP GRAPH, ACM, SIGGRAPH C1 COMP SCI CORP,NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 BN 0-8186-3940-7 PY 1993 BP 32 EP & PG 0 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BZ58G UT WOS:A1993BZ58G00004 ER PT B AU MA, KL SMITH, PJ AF MA, KL SMITH, PJ BE Nielson, GM Bergeron, D TI CLOUD TRACING IN CONVECTION-DIFFUSION SYSTEMS SO VISUALIZATION 93, PROCEEDINGS LA English DT Proceedings Paper CT Visualization 93, the 4th Annual IEEE Conference on Visualization CY OCT 25-29, 1993 CL SAN JOSE, CA SP IEEE, COMP SOC, TECH COMM COMP GRAPH, ACM, SIGGRAPH C1 NASA,LANGLEY RES CTR,ICASE,HAMPTON,VA 23681. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 BN 0-8186-3940-7 PY 1993 BP 253 EP & PG 0 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BZ58G UT WOS:A1993BZ58G00032 ER PT J AU STEVENS, R PINTO, J MAMANE, Y ONDOV, J ABDULRAHEEM, M ALMAJED, N SADEK, M COFER, W ELLENSON, W KELLOGG, R AF STEVENS, R PINTO, J MAMANE, Y ONDOV, J ABDULRAHEEM, M ALMAJED, N SADEK, M COFER, W ELLENSON, W KELLOGG, R TI CHEMICAL AND PHYSICAL-PROPERTIES OF EMISSIONS FROM KUWAITI OIL FIRES SO WATER SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL CONF OF THE ISRAEL SOC FOR ECOLOGY AND ENVIRONMENTAL QUALITY : ENVIRONMENTAL QUALITY AND ECOSYSTEM STABILITY CY JUN 21-26, 1992 CL JERUSALEM, ISRAEL SP ISRAEL SOC ECOL & ENVIRONM QUAL, BEN GURION UNIV NEGEV, ISRAEL OCEANOG & LIMNOL RES, KAREN KAYAMET LEISRAEL, RAV BARIAH, TECHNION, ISRAEL INST TECHNOL, TEL AVIV UNIV DE HELICOPTER SAMPLING; KUWAIT OIL FIRES; AEROSOL PLUME CHARACTERIZATION; AEROSOL SAMPLING; GLOBAL CLIMATE ID PARTICULATE AB After the Iraqi retreat from Kuwait in 1991, airborne sampling was conducted in the oil fire plumes near Kuwait City and ground-level samples were taken of the air within the city. For the airborne sampling, a versatile air pollution sampler was used to determine the SO2, elemental concentrations, the aerosol mass loadings and SO42- and NO3- concentrations. Striking differences between the black and white plumes were associated with high concentrations of NaCl and CaCl2 measured in the white plumes and large numbers of carbon chain agglomerates in the black plumes. For the ground-based measurements, an annular denuder system was used to determine levels of SO2, SO42-, trace elements, and mass loadings. Certain pollutant levels rose in the city during inversion conditions, when winds were too weak to continue moving the combustion products directly to the Persian Gulf, and the increased levels of Pb and certain trace elements were comparable to those in other large urban areas in Europe. This paper has been reviewed in accordance with the U.S. Environmental Protection Agency's peer and administrative review policies and approved for presentation and publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. C1 UNIV MARYLAND,DEPT CHEM,COLL PK,MD 20742. KUWAIT ENVIRONM PROTECT DEPT,KUWAIT,KUWAIT. MANTECH ENVIRONM TECHNOL INC,RES TRIANGLE PK,NC 27709. NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP STEVENS, R (reprint author), US EPA,RES TRIANGLE PK,NC 27711, USA. RI Ondov, John/B-6605-2009 NR 16 TC 29 Z9 29 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0273-1223 J9 WATER SCI TECHNOL JI Water Sci. Technol. PY 1993 VL 27 IS 7-8 BP 223 EP 233 PG 11 WC Engineering, Environmental; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA LL943 UT WOS:A1993LL94300029 ER PT B AU ROSS, MD DOSHAY, DG AF ROSS, MD DOSHAY, DG GP INT NEURAL NETWORK SOC TI VESTIBULAR MACULAR CIRCUITRY - A PROTOTYPIC NEURAL ARCHITECTURE SO WCNN'93 - PORTLAND, WORLD CONGRESS ON NEURAL NETWORKS, VOL II LA English DT Proceedings Paper CT World Congress on Neural Networks (WCNN 93, Portland) CY JUL 11-15, 1993 CL PORTLAND, OR SP INT NEURAL NETWORK SOC C1 NASA,AMES RES BIOCOMPUTAT CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC PUBL PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430 BN 0-8058-1497-3 PY 1993 BP 598 EP 601 PG 4 WC Computer Science, Artificial Intelligence; Neurosciences SC Computer Science; Neurosciences & Neurology GA BA45V UT WOS:A1993BA45V00134 ER PT B AU LEE, SK CHOI, YW AF LEE, SK CHOI, YW GP INT NEURAL NETWORK SOC TI UNCONSTRAINED HANDWRITTEN ZIP CODE RECOGNITION SO WCNN'93 - PORTLAND, WORLD CONGRESS ON NEURAL NETWORKS, VOL III LA English DT Proceedings Paper CT World Congress on Neural Networks (WCNN 93, Portland) CY JUL 11-15, 1993 CL PORTLAND, OR SP INT NEURAL NETWORK SOC C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC PUBL PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430 BN 0-8058-1497-3 PY 1993 BP 761 EP 766 PG 6 WC Computer Science, Artificial Intelligence; Neurosciences SC Computer Science; Neurosciences & Neurology GA BA45W UT WOS:A1993BA45W00163 ER PT B AU LEE, S PARK, J AF LEE, S PARK, J GP INT NEURAL NETWORK SOC TI AN OPTIMIZATION NEURAL-NETWORK WITH DUAL-MODE NETWORK DYNAMICS SO WCNN'93 - PORTLAND, WORLD CONGRESS ON NEURAL NETWORKS, VOL IV LA English DT Proceedings Paper CT World Congress on Neural Networks (WCNN 93, Portland) CY JUL 11-15, 1993 CL PORTLAND, OR SP INT NEURAL NETWORK SOC C1 JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC PUBL PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430 BN 0-8058-1497-3 PY 1993 BP 407 EP 414 PG 8 WC Computer Science, Artificial Intelligence; Neurosciences; Physics, Mathematical SC Computer Science; Neurosciences & Neurology; Physics GA BA45X UT WOS:A1993BA45X00089 ER PT B AU TAWEL, R AF TAWEL, R GP INT NEURAL NETWORK SOC TI ASSOCIATIVE MEMORY RECALL USING CASCADABLE ANALOG NEUROPROCESSORS SO WCNN'93 - PORTLAND, WORLD CONGRESS ON NEURAL NETWORKS, VOL IV LA English DT Proceedings Paper CT World Congress on Neural Networks (WCNN 93, Portland) CY JUL 11-15, 1993 CL PORTLAND, OR SP INT NEURAL NETWORK SOC C1 JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC PUBL PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430 BN 0-8058-1497-3 PY 1993 BP 865 EP 868 PG 4 WC Computer Science, Artificial Intelligence; Neurosciences; Physics, Mathematical SC Computer Science; Neurosciences & Neurology; Physics GA BA45X UT WOS:A1993BA45X00184 ER PT B AU BAAKLINI, GY AF BAAKLINI, GY BE Orphan, VJ TI ADVANCED COMPOSITES CHARACTERIZATION WITH X-RAY TECHNOLOGIES SO X-RAY DETECTOR PHYSICS AND APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Detector Physics and Applications II CY JUL 13-14, 1993 CL SAN DIEGO, CA SP SOC PHOTO OPT INSTRUMENTAT ENGINEERS C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-1258-9 J9 P SOC PHOTO-OPT INS PY 1993 VL 2009 BP 216 EP 228 DI 10.1117/12.164740 PG 13 WC Instruments & Instrumentation; Optics SC Instruments & Instrumentation; Optics GA BZ74V UT WOS:A1993BZ74V00022 ER PT J AU ASTHANA, R ROHATGI, PK AF ASTHANA, R ROHATGI, PK TI MELT INFILTRATION OF SILICON-CARBIDE COMPACTS .2. EVALUATION OF SOLIDIFICATION MICROSTRUCTURES SO ZEITSCHRIFT FUR METALLKUNDE LA English DT Article ID MATRIX; COMPOSITES AB Microstructural aspects of alloy solidification within the interstices of porous compacts of platelet-shaped single crystals of alpha-SiC, when the latter are infiltrated with a hot metal under pressure, have been described. Microstructural evidence is presented of selective reorientation of platelets and non-homogeneous solute distribution under shear of pressurized melt, of constrained growth of primary solid within finite width zones and of the modulation of coring due to microsegregation as a result of variations in the pore size of compacts. C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44030. UNIV WISCONSIN,DEPT MAT,MILWAUKEE,WI 53211. RP ASTHANA, R (reprint author), CLEVELAND STATE UNIV,DEPT CHEM ENGN,E 24TH EUCLID AVE,CLEVELAND,OH 44116, USA. NR 9 TC 6 Z9 6 U1 0 U2 1 PU CARL HANSER VERLAG PI MUNICH PA KOLBERGERSTRASSE 22, POSTFACH 860420, W-8163 MUNICH, GERMANY SN 0044-3093 J9 Z METALLKD JI Z. Metallk. PD JAN PY 1993 VL 84 IS 1 BP 44 EP 47 PG 4 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA KM592 UT WOS:A1993KM59200007 ER PT J AU MEARNS, LO ROSENZWEIG, C GOLDBERG, R AF MEARNS, LO ROSENZWEIG, C GOLDBERG, R TI EFFECT OF CHANGES IN INTERANNUAL CLIMATIC VARIABILITY ON CERES-WHEAT YIELDS - SENSITIVITY AND 2 X CO2 GENERAL-CIRCULATION MODEL STUDIES SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article ID SIMULATION; EUROPE AB This study concerns the investigation of how changes in climate variability could affect agricultural production. To date very few studies of this effect have been made, whereas changes in climate variability, in addition to changes in mean conditions could have serious effects on crops. Currently there is very little certainty regarding how climate variability will change in a greenhouse-gas-warmed world. In view of this uncertainty, it is desirable to perform sensitivity analyses of how crop-climate models (e.g. the CERES-Wheat model) respond to changes in climate variability. We apply the winter wheat model to two climate stations in the wheat growing region of Kansas: Goodland in the western region, and Topeka in the moister eastern region. Time series of temperature and precipitation, are simulated, systematically changing the interannual variance of the series (from one quarter to four times the actual variance), and determining how the crop climate model responds to these changes. In addition, these variability changes are combined with mean changes of both temperature and precipitation. We then also apply a GCM-derived climate change scenario. Results indicate that it is the relative magnitude of change of the mean and variance of the climate that determines their relative importance to changes in wheat yields. In general increases in variability of temperature and precipitation resulted in significant increases in yield variability and crop failures in the sensitivity experiments, but precipitation changes had a more pronounced effect. In the GCM-derived scenario, mean temperature effects dominate, resulting in increased yield variability and crop failures, because the magnitude of mean change is much greater than the magnitude of variance change. Over all experiments, the importance of considering not only mean but also variance changes of climate variables, when investigating the effect of climate change on wheat yields, is confirmed. C1 GODDARD INST SPACE STUDIES,NEW YORK,NY 10025. RP MEARNS, LO (reprint author), NATL CTR ATMOSPHER RES,POB 3000,BOULDER,CO 80307, USA. NR 36 TC 79 Z9 81 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD DEC 31 PY 1992 VL 62 IS 3-4 BP 159 EP 189 DI 10.1016/0168-1923(92)90013-T PG 31 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA KF063 UT WOS:A1992KF06300002 ER PT J AU LIOU, WWW MORRIS, PJ AF LIOU, WWW MORRIS, PJ TI THE EIGENVALUE SPECTRUM OF THE RAYLEIGH EQUATION FOR A PLANE SHEAR-LAYER SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article ID COORDINATE C1 PENN STATE UNIV,DEPT AEROSP ENGN,UNIV PK,PA 16802. RP LIOU, WWW (reprint author), NASA,LEWIS RES CTR,ICOMP,CTR MODELING TURBULENCE & TRANSIT,CLEVELAND,OH 44135, USA. NR 11 TC 8 Z9 8 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0271-2091 J9 INT J NUMER METH FL JI Int. J. Numer. Methods Fluids PD DEC 30 PY 1992 VL 15 IS 12 BP 1407 EP 1415 DI 10.1002/fld.1650151204 PG 9 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA KB753 UT WOS:A1992KB75300003 ER PT J AU GARVIN, JB SCHNETZLER, CC GRIEVE, RAF AF GARVIN, JB SCHNETZLER, CC GRIEVE, RAF TI CHARACTERISTICS OF LARGE TERRESTRIAL IMPACT STRUCTURES AS REVEALED BY REMOTE-SENSING STUDIES SO TECTONOPHYSICS LA English DT Article ID CRATER; METAMORPHISM; IMAGES; EARTH; VENUS; ROCKS AB Remote sensing data sets of a spectrum of impact structures on Earth have been analyzed in an effort to determine if such structures have identifiable signatures which could be used as an aid in searching broad areas for the ''missing craters'' predicted by current estimates of the cratering flux. Meteor Crater, Arizona has been used as a ''control'' site, due to the extensive data available for this feature. Laboratory thermal infrared reflectance spectra of shocked sandstones indicate that shock processes alter the appearance of fundamental absorption features enough to permit such effects to be observed in airborne thermal infrared imagery collected with the NASA TIMS instrument. Analysis of this TIMS imagery suggests that shocked and displaced target rocks can be readily identified. Aircraft multi-frequency imaging radar data collected with the NASA/JPL SAR polarimeter clearly reveals the textural pattern of the preserved components of the ejecta blanket. SPOT multi-spectral imagery of Bosumtwi, Ghana, illustrates the difficulties associated with remote sensing in highly vegetated terrains. Nevertheless, the imagery reveals the subtle expression of an outer tectonic ring at the crater, and may be sensitive to geobotanical variations associated with impact-related suevite deposits. In contrast, the Zhamanshin impact feature on the arid, sedimentary plains of Kazakhstan is ideal for multi-spectral remote sensing, although much of the expected morphologic expression of the complex crater is missing or subdued. Virtually all of the field-mapped impact-related deposits display a unique spectral pattern in decorrelated Landsat Thematic Mapper imagery. The extensive deposits of allogenic breccias, which cap the hills defining the inner ring of the crater, are very distinctive, as are certain of the impact glass deposits. A second, OT outer, ring at 13-13.5 km is apparent in the decorrelated principal component TM imagery. The suggestion is that spectral disruption patterns for large, multi-ring impact features in arid settings should be identifiable from orbit. By examining a pristine 144 km diameter multi-ring impact feature on the Venus rolling plains, an impression of the original morphology of a continental impact crater of the magnitude of the Cretaceous-Tertiary (K/T) boundary impact structure can be deduced. The 35 Ma Popigai structure is the only known 100 km class impact crater on Earth approximately equal in age or younger than the K/T event, and its morphology is poorly expressed in single-band Landsat imagery. Thus, spectral anomalies associated with key impact deposits, such as allogenic breccias, suevite, melt, and glasses may have to form the basis for identifying candidate K/T impact sites in the absence of preserved morphologic elements of the crater. It is apparent that remote sensing is not a panacea for the discovery and validation of new impact craters, but it can contribute by serving as a pathfinder both for the identification of promising structures and the possible locations of key deposits for detailed fieldwork and sampling. C1 GEOL SURVEY CANADA,DIV GEOPHYS,OTTAWA K1A 0Y3,ON,CANADA. RP GARVIN, JB (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 921,GREENBELT,MD 20771, USA. NR 50 TC 14 Z9 14 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-1951 J9 TECTONOPHYSICS JI Tectonophysics PD DEC 30 PY 1992 VL 216 IS 1-2 BP 45 EP 62 DI 10.1016/0040-1951(92)90155-Y PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KG551 UT WOS:A1992KG55100005 ER PT J AU MILLER, RH SMITH, BF AF MILLER, RH SMITH, BF TI LONGEVITY OF DISKS IN GALAXIES SO ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article ID DUST LANES; ELLIPTICAL GALAXIES; RADIO GALAXIES; OSCILLATIONS; EVOLUTION; PROLATE; WARPS C1 NASA, AMES RES CTR, THEORET STUDIES BRANCH, MOFFETT FIELD, CA 94035 USA. RP UNIV CHICAGO, DEPT ASTRON & ASTROPHYS, CHICAGO, IL 60637 USA. NR 32 TC 0 Z9 0 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 E 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PD DEC 28 PY 1992 VL 675 BP 227 EP 244 DI 10.1111/j.1749-6632.1992.tb56806.x PG 18 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KV090 UT WOS:A1992KV09000023 ER PT J AU WARD, WR AF WARD, WR TI DISK PROTOPLANET INTERACTIONS - TORQUES FROM THE COORBITAL ZONE SO ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article ID PRIMORDIAL SOLAR NEBULA; DENSITY WAVES; PLANET; LINDBLAD RP WARD, WR (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 15 TC 5 Z9 5 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 E 63RD ST, NEW YORK, NY 10021 SN 0077-8923 J9 ANN NY ACAD SCI JI Ann. N.Y. Acad. Sci. PD DEC 28 PY 1992 VL 675 BP 314 EP 323 DI 10.1111/j.1749-6632.1992.tb56814.x PG 10 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KV090 UT WOS:A1992KV09000031 ER PT J AU NEWELL, RE NEWELL, NE ZHU, Y SCOTT, C AF NEWELL, RE NEWELL, NE ZHU, Y SCOTT, C TI TROPOSPHERIC RIVERS - A PILOT-STUDY SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOUTHERN AB Computations of daily global tropospheric water vapor flux values show the presence of a filamentary structure. The filaments, here called rivers, have lengths many times their widths and persist for many days while being translated through the atmosphere. They are present in data analysed for both 1984 and 1991. The water vapor flux maxima coincide quite closely to reflectivity features (averaged from wavelengths of 380 and 360 nm) as revealed by the Total Ozone Mapping Spectrometer (TOMS). It is suggested that the filamentary structure may also be present in other trace constituents. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP NEWELL, RE (reprint author), MIT,DEPT EARTH ATMOSPHER & PLANETARY SCI,ROOM 54-1824,CAMBRIDGE,MA 02139, USA. NR 16 TC 98 Z9 99 U1 3 U2 23 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 24 PY 1992 VL 19 IS 24 BP 2401 EP 2404 DI 10.1029/92GL02916 PG 4 WC Geosciences, Multidisciplinary SC Geology GA KG677 UT WOS:A1992KG67700011 ER PT J AU DONAHUE, TM HARTLE, RE AF DONAHUE, TM HARTLE, RE TI SOLAR-CYCLE VARIATIONS IN H+ AND D+ DENSITIES IN THE VENUS IONOSPHERE - IMPLICATIONS FOR ESCAPE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HYDROGEN; DEUTERIUM AB The hydrogen ion concentrations recently observed on Venus, near solar minimum, by the Ion Mass Spectrometer on the Pioneer Venus Orbiter in the anti-solar sector (22:00-02:00 LST) of the ionosphere are more than an order of magnitude less than those previously observed at solar maximum. This strong solar cycle variation has a profound effect on the escape of hydrogen (and deuterium) from Venus; almost all escape occurs during solar maximum. After adjustment for solar cycle variation, a planet-averaged hydrogen escape flux of 0.6-1.4 x 10(7) cm-2 s-1 is obtained along with a large deuterium fractionation factor of 0.1-0.14. These results suggest at least two plausible scenarios for the evolution of water on Venus: (1) Water vapor on Venus may be approaching a steady state if the escape flux is balanced by endogenous or exogenous sources of water. The source of water must be highly fractionated, with a D/H ratio differing by less than an order of magnitude from the present ratio of 2.4 x 10(-2), thus precluding low D/H water from comets, asteroids or a mantle reservoir. (2) The present day D/H ratio of 2.4 x 10(-2) could be established by Rayleigh fractionation of an early low D/H water reservoir if the escape flux was sufficiently large in earlier times. An early water endowment at least 340 times today's abundance, equivalent to 4.2 to 14 m of liquid water on the surface, would be needed. C1 NASA,GODDARD SPACE FLIGHT CTR,ATMOSPHERES LAB,GREENBELT,MD 20771. RP DONAHUE, TM (reprint author), UNIV MICHIGAN,DEPT ATMOSPHER OCEAN & SPACE SCI,SPACE PHYS RES LAB,ANN ARBOR,MI 48109, USA. NR 16 TC 16 Z9 16 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 24 PY 1992 VL 19 IS 24 BP 2449 EP 2452 DI 10.1029/92GL02927 PG 4 WC Geosciences, Multidisciplinary SC Geology GA KG677 UT WOS:A1992KG67700023 ER PT J AU OTTERMAN, J SUSSKIND, J DALU, G KRATZ, D GOLDBERG, IL AF OTTERMAN, J SUSSKIND, J DALU, G KRATZ, D GOLDBERG, IL TI EFFECTS OF WATER-EMISSION ANISOTROPY ON MULTISPECTRAL REMOTE-SENSING AT THERMAL WAVELENGTHS OF OCEAN TEMPERATURE AND OF CIRRUS CLOUDS SO APPLIED OPTICS LA English DT Article ID SEA-SURFACE TEMPERATURES; INFRARED EXTINCTION CHARACTERISTICS; POLAR-REGIONS; TRENDS AB The assumption of blackbody emission (emissivity, 1.0) for a calm ocean surface can lead to significant underestimates of the sea-surface temperature (SST) derived from IR radiometric data. Taking the optical properties of the atmosphere as known, we calculate the errors stemming from the blackbody assumption for cases of a purely absorbing or a purely scattering atmosphere. It is observed that for an absorbing atmosphere the errors in SST are always reduced and are the same whether measurements are made from space or at any level in the atmosphere. As for atmospheric scattering, the SST errors are slightly reduced when one is viewing from large zenith angles but are slightly enhanced when one is viewing from the zenith. The inferred optical thickness tau of an absorbing layer can be in error under the blackbody assumption by a DELTAtau of 0.01-0.08, while the inferred optical thickness of a scattering layer can be in error by a larger amount, DELTAtau of 0.03-0.13. The error DELTAtau depends only weakly on the actual optical thickness and on the viewing angle, but it is rather sensitive to the wavelength of the measurement. In the absence of steep slopes in the wave-slope distribution, directional emissivities are essentially unchanged by sea state when one is viewing from or near the zenith. When one is viewing from moderately large zenith angles (such as 50-degrees), however, the departures in the directional emissivities from blackbody emission can be much larger under perturbed sea state than under calm conditions. C1 TEL AVIV UNIV, IL-69978 TEL AVIV, ISRAEL. NASA, GODDARD SPACE FLIGHT CTR, UNIV SPACE RES ASSOCIATES, GREENBELT, MD 20771 USA. CNR, IST FIS ATMOSFERA, ROME, ITALY. RP OTTERMAN, J (reprint author), NASA, GODDARD SPACE FLIGHT CTR, CODE 911, GREENBELT, MD 20771 USA. NR 29 TC 5 Z9 6 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 20 PY 1992 VL 31 IS 36 BP 7633 EP 7646 PG 14 WC Optics SC Optics GA KF520 UT WOS:A1992KF52000019 PM 20802644 ER PT J AU NAKAJIMA, T KING, MD AF NAKAJIMA, T KING, MD TI ASYMPTOTIC THEORY FOR OPTICALLY THICK LAYERS - APPLICATION TO THE DISCRETE ORDINATES METHOD SO APPLIED OPTICS LA English DT Article DE MULTIPLE SCATTERING; RADIATIVE TRANSFER; ASYMPTOTIC THEORY; DISCRETE ORDINATES METHOD ID ANISOTROPICALLY SCATTERING ATMOSPHERES; RADIATIVE-TRANSFER CALCULATIONS; SOLAR-RADIATION; MULTIPLE-SCATTERING; CLOUDS AB Asymptotic expressions for the reflected, transmitted, and internal scattered radiation field in optically thick, vertically homogeneous, plane-parallel media are derived from first principles by using the discrete ordinates method of radiative transfer. Compact matrix equations are derived for computing the escape function, diffusion pattern, diffusion exponent, and the reflection function of a semi-infinite atmosphere in terms of the matrices, eigenvectors, and eigenvalues that occur in the discrete ordinates method. These matrix equations are suitable for numerical computations and are valid throughout the full range of single scattering albedos. The present formulations are validated by comparing them with established methods of radiative transfer. C1 NASA, GODDARD SPACE FLIGHT CTR, EARTH SCI DIRECTORATE, GREENBELT, MD 20771 USA. RP NAKAJIMA, T (reprint author), UNIV TOKYO, CTR CLIMATE SYST RES, 4-6-1 KOMABA, MEGURO KU, TOKYO 153, JAPAN. RI King, Michael/C-7153-2011; Nakajima, Teruyuki/H-2370-2013 OI King, Michael/0000-0003-2645-7298; Nakajima, Teruyuki/0000-0002-9042-504X NR 34 TC 33 Z9 33 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 20 PY 1992 VL 31 IS 36 BP 7669 EP 7683 PG 15 WC Optics SC Optics GA KF520 UT WOS:A1992KF52000023 PM 20802648 ER PT J AU DECKER, AJ IZEN, SH AF DECKER, AJ IZEN, SH TI 3-DIMENSIONAL COMPUTED-TOMOGRAPHY FROM INTERFEROMETRIC MEASUREMENTS WITHIN A NARROW CONE OF VIEWS SO APPLIED OPTICS LA English DT Article DE TOMOGRAPHY; INTERFEROMETRY; FLOW; HOLOGRAPHY ID FUNCTION SERIES EXPANSIONS; DENSITY FIELD; TRANSFORM; LASER AB A theory is presented and tested for recovering a fluid property from measurements of its projections. Viewing comes as small as 10-degrees are evaluated, and the only assumption is that the property is space limited. The results of applying the theory to numerical and actual interferograms of a spherical discontinuity of refractive index are presented. The theory was developed to test the practicality and limits of using three-dimensional computed tomography to process optical diagnostic data for internal fluid dynamics. C1 CASE WESTERN RESERVE UNIV, DEPT MATH & STAT, CLEVELAND, OH 44106 USA. RP DECKER, AJ (reprint author), NASA, LEWIS RES CTR, OPT MEASUREMENT SYST BRANCH, 21000 BROOKPARK RD, CLEVELAND, OH 44135 USA. NR 21 TC 4 Z9 4 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 20 PY 1992 VL 31 IS 36 BP 7696 EP 7706 PG 11 WC Optics SC Optics GA KF520 UT WOS:A1992KF52000026 PM 20802651 ER PT J AU WALLIO, HA CHAN, CC GORMSEN, BB REICHLE, HG AF WALLIO, HA CHAN, CC GORMSEN, BB REICHLE, HG TI DIFFERENTIAL CORRECTION TECHNIQUE FOR REMOVING COMMON ERRORS IN GAS FILTER RADIOMETER MEASUREMENTS SO APPLIED OPTICS LA English DT Article DE GAS FILTER RADIOMETER; SATELLITE DATA RETRIEVAL ALGORITHMS; CARBON MONOXIDE ID CARBON-MONOXIDE AB The Measurement of Air Pollution from Satellites (MAPS) ps filter radiometer experiment was designed to measure CO mixing ratios in the Earth's atmosphere. MAPS also measures N2O to provide a reference channel for the atmospheric emitting temperature and to detect the presence of clouds. In this paper we formulate equations to correct the radiometric signals based on the spatial and temporal uniformity of the N2O Mixing ratio in the atmosphere. Results of an error study demonstrate that these equations reduce the error in inferred CO mixing ratios. Subsequent application of the technique to the MAPS 1984 data set decreases the error in the frequency distribution of mixing ratios and increases the number of usable data points. C1 ST SYST CORP, HAMPTON, VA 23666 USA. RP WALLIO, HA (reprint author), NASA, LANGLEY RES CTR, DIV ATMOSPHER SCI, HAMPTON, VA 23665 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 20 PY 1992 VL 31 IS 36 BP 7716 EP 7724 PG 9 WC Optics SC Optics GA KF520 UT WOS:A1992KF52000028 PM 20802653 ER PT J AU EDELSON, R AF EDELSON, R TI A SURVEY OF ULTRAVIOLET VARIABILITY IN BLAZARS SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL LACERTAE OBJECTS, GENERAL; GALAXIES, PHOTOMETRY; QUASARS, GENERAL; ULTRAVIOLET, GALAXIES ID BL LACERTAE OBJECT; ACTIVE GALACTIC NUCLEI; ACCRETION DISKS; PKS 2155-304; SPECTRA; PKS-2155-304; GALAXIES; QUASARS; MODELS AB This is the first comprehensive, consistent survey of the ultraviolet variability properties of a large sample of blazars. All of the 14 blazars with five or more observations in a single IUE camera showed significant variability. The strength of the ultraviolet variability is positively correlated with both the apparent ultraviolet luminosity and the degree of optical polarization of the source. This is the first clear indication that the ultraviolet continua of blazars are beamed. A search for rapid variability yielded nine "events" with doubling time scales of 0.5-7 days. These rapid flux variations and correlations argue for the standard synchrotron self-Compton model, and against the accretion disk model, which would predict slower variations and the opposite sense of correlation. Other analyses were less decisive. Short wavelength variability was stronger than that at long wavelengths. Of the two blazars with at least 35 observations in each band, one, Mkn 421, shows a correlation between flux and spectral index, while the other, PKS 2155-304, does not. Both sources show correlations between changes in flux density and spectral index, but the physical meaning, if any, is unclear. These data are too sparsely and unevenly sampled for more ambitious time-series analyses to yield meaningful results. C1 UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,BOULDER,CO 80309. RP EDELSON, R (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,CODE 666,GREENBELT,MD 20771, USA. NR 43 TC 35 Z9 35 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP 516 EP 528 DI 10.1086/172083 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD149 UT WOS:A1992KD14900010 ER PT J AU MALONEY, PR HOLLENBACH, DJ TOWNES, CH AF MALONEY, PR HOLLENBACH, DJ TOWNES, CH TI HEATING OF H-II REGIONS WITH APPLICATION TO THE GALACTIC-CENTER SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXY, CENTER; GALAXIES, ISM; RADIATIVE TRANSFER; RADIO LINES, ATOMIC ID RECOMBINATION LINE OBSERVATIONS; CENTRAL PARSEC; SAGITTARIUS-A; IONIZED-GAS; X-RAY; GASEOUS NEBULAE; RADIO; GALAXY; IONIZATION; DYNAMICS AB Recent observations of the H76alpha (Schwarz, Bregman, & van Gorkom) and H92alpha (Roberts et al.) radio recombination lines from the northern arm and bar of Sagittarius A using the Very Large Array (VLA) have suggested that there is a sharp drop in the line-to-continuum ratio in the bar close to the compact nonthermal source Sgr A*. If LTE is assumed, this implies that there is a dramatic increase of the electron temperature, with temperatures rising to T(e) approximately 50,000 K at r approximately 0.25 pc from Sgr A*. In this paper we review the heating and thermal equilibrium of photoionized gas and show that such high temperatures are implausible. Photon-heating mechanisms (UV photoionization heating, grain photoelectric heating, and X-ray heating) either fail to provide the required heating rates or else require that the ionization state of the gas is very high. Gas which is collisionally ionized and heated in shocks can reach high temperatures, but only over a limited range of column densities. Specific application to the Galactic center observations show that the total heating power required to maintain the gas at the derived temperatures, using the observed emission measure in the bar and the temperature distribution derived from the radio recombination lines, is approximately 7 x 10(6) L., comparable to the bolometric luminosity of the central source as measured by the far-infrared flux from grains. Thus, the cooling emission from this hot gas, if the LTE-derived temperatures are correct, would supply a major fraction of the bolometric and ionizing luminosity inferred from the ionized gas in the central 1 pc cavity and the dust and neutral gas in the surrounding torus. Photoionization and grain photoelectric heating fail as sources of the heating power by large factors. While X-ray heating can produce sufficiently high temperatures, it also violates the constraints on the ionization level of the gas in the bar and requires X-ray fluxes exceeding the observed upper limit for Sgr A* by orders of magnitude. Shock-heating can easily produce high gas temperatures, but the column density of gas at temperatures of a few times 10(4) K in shocks is small, requiring a very ad hoc superposition of a large number of shocks, which must also be truncated in column density so the emission measure is not dominated by the 10(4) K postshock gas. A number of more speculative heating mechanisms have also been considered, but are either inadequate or so ad hoc as to be implausible. Failure to find any reasonable mechanism for maintaining the gas at these temperatures, plus the disagreement between the observed Bralpha-to-radio-continuum ratio and that predicted for T(e) approximately 50,000 K gas, provide strong evidence that the gas is in fact at T(e) almost-equal-to 10,000 K and that either observational error or another physical mechanism has produced the low line-to-continuum ratios. We find no physical mechanism that is not ruled out by observations. Nevertheless, we feel that the evidence favors a normal electron temperature (T(e) approximately 10(4) K) for the bar. We propose several additional probes of this mysterious region. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP MALONEY, PR (reprint author), NASA,AMES RES CTR,MS 245-6,MOFFETT FIELD,CA 94035, USA. NR 54 TC 7 Z9 7 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP 559 EP 573 DI 10.1086/172086 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD149 UT WOS:A1992KD14900013 ER PT J AU CANNIZZO, JK MATTEI, JA AF CANNIZZO, JK MATTEI, JA TI ON THE LONG-TERM BEHAVIOR OF SS CYGNI SO ASTROPHYSICAL JOURNAL LA English DT Article DE ACCRETION, ACCRETION DISKS; NOVAE, CATACLYSMIC VARIABLES; STARS, INDIVIDUAL (SS CYG) ID ANGULAR-MOMENTUM TRANSPORT; X-RAY BINARIES; ACCRETION DISKS; DWARF NOVAE; MASS; MECHANISM; CYCLES; LIGHT AB We examine the complete historical light curve of the dwarf nova SS Cygni taken by the American Association of Variable Star Observers which spans more than 95 yr: from 1896 September 27 to 1992 April 7. The data consist of 29,387 daily means based on 180,233 individual observations. We investigate the statistical properties of the outburst durations, quiescence intervals, and cycle times associated with the 705 outbursts which occurred during this time. Our findings for the general properties of these time scales are in accord with previous studies. However, we find that correlations found by some earlier workers were artifacts of inconsistencies in their analyses. In particular, we find no significant difference between the correlations of (1) the duration of a burst with the length of the following cycle time and (2) the duration of a burst with the length of the preceding cycle time. By considering long-term moving averages we confirm an inverse relation between cycle time and quiescent magnitude pointed out previously by Warner. We use the accretion disk limit cycle computations of Duschl & Livio to infer from this relation that the mass transfer rate M(T) greater-than-or-similar-to 1 X 10(-9) M. yr-1 in SS Cyg. If we assume (1) the bright spot contributes approximately 25% to the quiescent visual flux, (2) variations of a given amplitude in M(T) produce variations of a similar amplitude in the bright spot flux, and (3) the observed fluctuations in the quiescent magnitude are primarily due to secular changes in M(T), then from the amplitude of the fluctuations in the quiescent magnitudes we infer that M(T) can vary by as much as about a factor of 2 on a time scale of several years, and by a smaller amount on longer time scales. In addition, the quiescent state appears to have undergone a secular decrease in brightness of approximately 0.1 mag over the past approximately 100 yr. C1 AMER ASSOC VARIABLE STAR OBSERVERS,CAMBRIDGE,MA 02138. RP CANNIZZO, JK (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GSFC,LASP,CODE 681,GREENBELT,MD 20771, USA. NR 35 TC 64 Z9 64 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP 642 EP 653 DI 10.1086/172092 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD149 UT WOS:A1992KD14900019 ER PT J AU ANDRE, P DEENEY, BD PHILLIPS, RB LESTRADE, JF AF ANDRE, P DEENEY, BD PHILLIPS, RB LESTRADE, JF TI VLBI SURVEY OF RHO-OPHIUCHI - A POPULATION OF MAGNETIZED, DISKLESS YOUNG STELLAR OBJECTS SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM, INDIVIDUAL (RHO-OPHIUCHI); RADIO CONTINUUM, STARS; STARS, PRE-MAIN-SEQUENCE ID T-TAURI STARS; MAIN-SEQUENCE STARS; RADIO-CONTINUUM OBSERVATIONS; DARK CLOUD COMPLEX; INFRARED OBSERVATIONS; CIRCUMSTELLAR DISKS; EMISSION; CLUSTER; AURIGA; PROTOSTARS AB In the past years, extensive radio-continuum surveys conducted with the Very Large Array (VLA) have shown that only approximately 10 of the approximately 100 young stellar objects (YSOs) embedded in the central region of the rho Oph molecular cloud have "strong" radio emission above S6 cm = 1 mJy. Two of these rho Oph radio stars, S1 and DoAr 21, have recently been detected and resolved by very long baseline interferometry (VLBI), implying that their radio emission is "peristellar," i.e., originates in magnetic structures up to approximately 25 R* in diameter. We report here VLBI observations of nine other rho Oph YSOs, yielding positive detections in five cases (VSSG 14, WL 5, ROC 16, ROX 39, and VSSG 11), with flux densities ranging from 1.2 to 9 mJy at 3.6 cm. In contrast, while simultaneously detected by the VLA at levels of a few mJy, the protostellar outflow source IRAS 16293 and the "protostar" candidate YLW 15 were apparently overresolved and undetected on the VLA-Goldstone baseline. The radio emission from the young A star VSSG 14 was measured to be circularly polarized, at a level (approximately 6%) comparable to what had previously been observed for the embedded magnetic B star SI. The brightness temperatures (T(b)) measured for the VLBI detected YSOs range from approximately 10(7) to greater than or similar to 8 x 10(7) K, unambiguously establishing that these radio sources are nonthermal, and not the result of circumstellar ionized winds as is probably the case for IRAS 16293 and YLW 15. The present VLBI observations thus confirm our earlier suggestion that most "strong" (S6 cm greater than or similar to 1 mJy) stellar radio sources of rho Oph are magnetic in character (i.e., nonthermal). When optically visible, these radio emitters are associated with " weak-line " T Tauri stars (DoAr 2 1, ROX 39) or young B-A stars without emission lines (S1 and VSSG 14). Others are optically invisible, low-luminosity YSOs with no or little infrared excesses (e.g., WL 5, VSSG 11). It appears that these nonthermal radio emitters make up a specific class of YSOs characterized by the absence of dense circumstellar disks and the presence of extended, organized magnetic structures reminiscent of those found around magnetic Bp-Ap stars. Remarkably, the magnetized radio YSOs of rho Oph are spatially more concentrated toward the cloud core than the majority of T Tauri stars, suggesting they are younger. Some of the youngest YSOs may thus be already "naked." It is tempting to speculate that, compared to classical T Tauri stars, the diskless, nonthermal radio stars have conserved particularly strong fossil magnetic fields, which caused fast clearing of their circumstellar material. C1 ASSOCIATED UNIV INC,NATL RADIO ASTRON OBSERV,TUCSON,AZ 85721. VILLANOVA UNIV,DEPT ASTRON & ASTROPHYS,VILLANOVA,PA 19085. MIT,HAYSTACK OBSERV,WESTFORD,MA 01886. CALTECH,JET PROP LAB,PASADENA,CA 91106. RP ANDRE, P (reprint author), CTR ETUDES SACLAY,SERV ASTROPHYS,F-91191 GIF SUR YVETTE,FRANCE. NR 66 TC 65 Z9 65 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP 667 EP 677 DI 10.1086/172094 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD149 UT WOS:A1992KD14900021 ER PT J AU MICHELSON, PF BERTSCH, DL CHIANG, J FICHTEL, CE HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA KWOK, PW LIN, YC MATTOX, JR MAYERHASSELWANDER, HA VONMONTIGNY, C NOLAN, PL PINKAU, K ROTHERMEL, H SCHNEID, E SOMMER, M SREEKUMAR, P THOMPSON, DJ AF MICHELSON, PF BERTSCH, DL CHIANG, J FICHTEL, CE HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA KWOK, PW LIN, YC MATTOX, JR MAYERHASSELWANDER, HA VONMONTIGNY, C NOLAN, PL PINKAU, K ROTHERMEL, H SCHNEID, E SOMMER, M SREEKUMAR, P THOMPSON, DJ TI SEARCH FOR PERIODIC GAMMA-RAY EMISSION FROM CYGNUS-X-3 BY THE EGRET TELESCOPE ON THE COMPTON-GAMMA-RAY-OBSERVATORY SO ASTROPHYSICAL JOURNAL LA English DT Article DE GAMMA-RAYS, OBSERVATIONS; STARS, INDIVIDUAL (CYGNUS X-3) ID X-RAY; MILLISECOND PULSAR; MASS-TRANSFER; BINARIES; EVOLUTION AB The Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory observed the Cygnus region of the Galaxy during the periods 1991 May 30-June 8 and 1991 August 8-15. We report on a periodicity analysis of the gamma rays originating from the direction of Cygnus X-3. This analysis showed no evidence of periodic modulation during these observations of the gamma-ray emission at the approximately 4.8 hr period observed at X-ray wavelengths. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. MAX PLANCK INST EXTRATERRESTR PHYS,W-8046 GARCHING,GERMANY. HAMPDEN SYDNEY COLL,HAMPDEN SYDNEY,VA 23943. NASA,GODDARD SPACE FLIGHT CTR,GSFC,NAS,NRC POSTDOCTORAL RES ASSOCIATE,GREENBELT,MD 20771. NASA,GODDARD SPACE FLIGHT CTR,GSFC,COMP SCI CORP,COMPTON OBSERV SCI SUPPORT CTR,GREENBELT,MD 20771. GRUMMAN AEROSP CORP,BETHPAGE,NY 11714. NASA,GODDARD SPACE FLIGHT CTR,GSFC,UNIV SPACE RES ASSOC,GREENBELT,MD 20771. RP MICHELSON, PF (reprint author), STANFORD UNIV,HANSEN EXPTL PHYS LAB,STANFORD,CA 94305, USA. RI Nolan, Patrick/A-5582-2009; Hunter, Stanley/D-2942-2012; Thompson, David/D-2939-2012 OI Thompson, David/0000-0001-5217-9135 NR 32 TC 10 Z9 10 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP 724 EP 727 DI 10.1086/172099 PN 1 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD149 UT WOS:A1992KD14900026 ER PT J AU ASCHWANDEN, MJ GUDEL, M AF ASCHWANDEN, MJ GUDEL, M TI THE COEVOLUTION OF DECIMETRIC MILLISECOND SPIKES AND HARD X-RAY-EMISSION DURING SOLAR-FLARES SO ASTROPHYSICAL JOURNAL LA English DT Article DE SUN, FLARES; SUN, RADIO RADIATION; SUN, X-RAYS, GAMMA-RAYS ID CYCLOTRON MASER INSTABILITY; BROAD-BAND SPECTROMETER; MICROWAVE RADIO-BURSTS; ENERGY-RELEASE; ELECTRON ACCELERATION; HARMONIC EMISSION; WAVE GROWTH; CORONA; POLARIZATION; SOFT AB A comprehensive data set of 27 solar flares with decimetric millisecond spikes between 1980 and 1989, simultaneously observed with the Zurich radio spectrometers (Ikarus, 0.1-1 GHz; Phoenix, 0.1-3 GHz) and the Hard X-Ray Burst Spectrometer (HXRBS, 25-500 keV on the Solar Maximum Mission (SMM) spacecraft, has been analyzed. A strong functional dependence was found between the radio spike flux and.the associated 25-50 keV hard X-ray emission, which can be expressed by a convolution of both flux time profiles with a delayed Gaussian kernel. From this convolution technique, we obtain the following results: (1) the delayed radio spike flux is best reproduced during the rise and decay of the impulsive hard X-ray (HXR) phase, (2) the smoothed radio spike flux is delayed by typically 2-5 s, and (3) there are correlations among the radio flux, the spike modulation depth of HXR flux, the HXR-radio delay, and the radio frequency. In order to study the evolution of the radio spike burst rate, we developed an algorithm that discriminates spike bursts against instrumental noise and irrelevant burst types. This counting algorithm yields the following results: (1) the total number of spikes per cluster varies from 10 to 10(4), (2) the maximum spike rate varies from 5 up to 100 s-1, (3) the irradiated radio energy per single spike is 10(16)-10(18) ergs, (4) the correlated photon flux per single radio spike is 0.1-10 photons (cm2 keV)-1 in the 25-50 keV range, and (5) the single radio spikes (with a duration of 20-100 ms) do not show corresponding fine structures in hard X-rays. However, the spatial dispersion of precipitating beams, the finite energy loss time, and the instrumental sensitivity can obscure possible HXR fine structures beyond a few tenths of a second. A number of scenarios are discussed which can account for the observed delay of 2-5 s between HXR and spiky radio emission: (1) propagation effects, (2) particle trapping, (3) anisotropic acceleration, (4) trigger by shock waves or conduction fronts, and (5) nonlinear threshold effects for coherent radio emission. Although the observed proportionality between the HXR flux and the delayed radio spike rate suggests a functional relationship between both emission mechanisms, no conclusive evidence can be drawn as to whether the spikiness in radio emission results from a possibly fragmented energy release or from secondary effects related to particle propagation and plasma instabilities in an inhomogeneous medium. C1 NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. SWISS FED INST TECHNOL,INST ASTRON,CH-8092 ZURICH,SWITZERLAND. RP ASCHWANDEN, MJ (reprint author), UNIV MARYLAND,DEPT ASTRON,COLL PK,MD 20742, USA. RI Guedel, Manuel/C-8486-2015 OI Guedel, Manuel/0000-0001-9818-0588 NR 56 TC 74 Z9 76 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP 736 EP 753 DI 10.1086/172101 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD149 UT WOS:A1992KD14900028 ER PT J AU MARISKA, JT DOWDY, JF AF MARISKA, JT DOWDY, JF TI SOLAR DOPPLER-SHIFT MEASUREMENTS IN THE NE-VII 465-ANGSTROM EMISSION-LINE SO ASTROPHYSICAL JOURNAL LA English DT Article DE SUN, TRANSITION REGION; SUN, UV RADIATION ID TRANSITION REGION; QUIET SUN AB Using a Dopplergram obtained with the Naval Research Laboratory extreme ultraviolet spectrograph on Skylab, we have searched for Doppler shifts in the Ne VII 465 angstrom emission line, which is formed at a temperature of approximately 5 x 10(5) K. In the quiet Sun we find no measurable average Doppler shift to a measurement accuracy of +/- 18 km s-1. Small regions of the quite Sun do, however, display measurable Doppler shifts. In active regions, we measure Doppler shifts indicating downflow velocities of up to 70 km s-1. C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,SPACE SCI LAB,HUNTSVILLE,AL 35812. RP MARISKA, JT (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,CODE 7671,WASHINGTON,DC 20375, USA. NR 11 TC 14 Z9 14 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP 754 EP 758 DI 10.1086/172102 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD149 UT WOS:A1992KD14900029 ER PT J AU LANDSMAN, WB ROBERTS, MS BOHLIN, RC OCONNELL, RW SMITH, AM STECHER, TP AF LANDSMAN, WB ROBERTS, MS BOHLIN, RC OCONNELL, RW SMITH, AM STECHER, TP TI THE ULTRAVIOLET COLOR GRADIENT IN THE LATE-TYPE SPIRAL GALAXY-M33 SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, INDIVIDUAL (M33); GALAXIES, PHOTOMETRY; ULTRAVIOLET, GALAXIES ID H-II REGIONS; NEARBY GALAXIES; M-33; M33; EXTINCTION; PHOTOMETRY; HYDROGEN; GAS AB The ultraviolet surface brightness and color distributions for the late-type spiral galaxy M33 are derived from images at 1520 and 2490 angstrom that were obtained by the Ultraviolet Imaging Telescope (UIT) on the Astro Spacelab mission. Although the surface brightness shows a general decline with radius, the dominant spiral arms cause significant deviations from an exponential fit. Colors in elliptical annuli become 0.2-0.3 mag bluer with increasing radius. Our measures of individual H II regions and sections of spiral arms follow this same trend. Interarm regions are redder than the arms. A metallicity gradient affecting only the colors of stars is inadequate in accounting for the observed color gradient. A plausible explanation invokes a combination of an LMC-type reddening curve and a radial gradient in the internal reddening in M33. C1 NATL RADIO ASTRON OBSERV,CHARLOTTESVILLE,VA 22903. UNIV VIRGINIA,DEPT ASTRON,CHARLOTTESVILLE,VA 22903. NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. RP LANDSMAN, WB (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HUGHES STX,CODE 681,GREENBELT,MD 20771, USA. NR 23 TC 17 Z9 17 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP L83 EP & DI 10.1086/186676 PN 2 PG 0 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD154 UT WOS:A1992KD15400009 ER PT J AU LIN, YC BERTSCH, DL CHIANG, J FICHTEL, CE HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA KWOK, PW MATTOX, JR MAYERHASSELWANDER, HA MICHELSON, PF VONMONTIGNY, C NOLAN, PL PINKAU, K SCHNEID, E SREEKUMAR, P THOMPSON, DJ AF LIN, YC BERTSCH, DL CHIANG, J FICHTEL, CE HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA KWOK, PW MATTOX, JR MAYERHASSELWANDER, HA MICHELSON, PF VONMONTIGNY, C NOLAN, PL PINKAU, K SCHNEID, E SREEKUMAR, P THOMPSON, DJ TI DETECTION OF HIGH-ENERGY GAMMA-RAY EMISSION FROM THE BL-LACERTAE OBJECT MARKARIAN-421 BY THE EGRET TELESCOPE ON THE COMPTON-OBSERVATORY SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL LACERTAE OBJECTS, INDIVIDUAL, MARKARIAN-421; GAMMA RAYS, OBSERVATIONS ID SIMULTANEOUS MULTIFREQUENCY OBSERVATIONS; COMPACT RADIO-SOURCES; X-RAY; RELATIVISTIC JETS; COS-B; CATALOG AB Gamma radiation in the energy range from 50 MeV to well over 1 GeV has been observed from the direction of the BL Lac object Markarian 421 by the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Observatory during the period 1991 June 27-July 11. The source flux is weak, but still statistically significant at the level of 10(-5); the integrated photon flux above 100 MeV is (1.4 +/- 0.3) x 10(-7) cm-2 s-1. The differential photon energy spectrum can be represented by a power law with exponent 1.96 +/- 0.14. This is the first detection of gamma-ray emission from a BL Lac object. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. MAX PLANCK INST EXTRATERRESTR PHYS,W-8046 GARCHING,GERMANY. NASA,GODDARD SPACE FLIGHT CTR,NAS,NRC,GREENBELT,MD 20771. NASA,GODDARD SPACE FLIGHT CTR,GRO SCI SUPPORT CTR,COMP SCI CORP,GREENBELT,MD 20771. GRUMMAN AEROSP CORP,BETHPAGE,NY 11714. NASA,GODDARD SPACE FLIGHT CTR,UNIV SPACE RES ASSOC,GREENBELT,MD 20771. HAMPDEN SYDNEY COLL,HAMPDEN SYDNEY,VA 23943. RP LIN, YC (reprint author), STANFORD UNIV,HANSEN EXPTL PHYS LAB,STANFORD,CA 94305, USA. RI Nolan, Patrick/A-5582-2009; Hunter, Stanley/D-2942-2012; Thompson, David/D-2939-2012 OI Thompson, David/0000-0001-5217-9135 NR 42 TC 74 Z9 76 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP L61 EP L64 DI 10.1086/186671 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD154 UT WOS:A1992KD15400004 ER PT J AU LUCCHIN, F MATARRESE, S MOLLERACH, S AF LUCCHIN, F MATARRESE, S MOLLERACH, S TI THE GRAVITATIONAL-WAVE CONTRIBUTION TO COSMIC MICROWAVE BACKGROUND ANISOTROPIES AND THE AMPLITUDE OF MASS FLUCTUATIONS FROM COBE RESULTS SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMIC BACKGROUND RADIATION; COSMOLOGY, OBSERVATIONS; COSMOLOGY, THEORY; EARLY UNIVERSE; GALAXIES, FORMATION ID GENERALIZED INFLATIONARY COSMOLOGIES; DENSITY-FLUCTUATIONS; RADIATION; UNIVERSE; VELOCITY; SPECTRUM AB A stochastic background of primordial gravitational waves may substantially contribute, via the Sachs-Wolfe effect, to the large-scale cosmic microwave background (CMB) anisotropies recently detected by COBE. This implies a bias in any resulting determination of the primordial amplitude of density fluctuations. We consider the constraints imposed on n < 1 ("tilted") power-law fluctuation spectra, taking into account the contribution from both scalar and tensor waves, as predicted by power-law inflation. The gravitational wave contribution to CMB anisotropies generally reduces the required rms level of mass fluctuation, thereby increasing the linear bias parameter, even in models where the spectral index is close to the Harrison-Zel'dovich value n = 1. This "gravitational wave bias" helps to reconcile the predictions of CDM models with observations on pairwise galaxy velocity dispersion on small scales. C1 UNIV PADUA,DIPARTIMENTO FIS GALILEO GALILEI,I-35131 PADUA,ITALY. NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. RP LUCCHIN, F (reprint author), UNIV PADUA,DIPARTIMENTO ASTRON,VICOLO OSSERVAT 5,I-35122 PADUA,ITALY. NR 35 TC 75 Z9 75 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1992 VL 401 IS 2 BP L49 EP L52 DI 10.1086/186668 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD154 UT WOS:A1992KD15400001 ER PT J AU KEPPENNE, CL GHIL, M AF KEPPENNE, CL GHIL, M TI ADAPTIVE FILTERING AND PREDICTION OF THE SOUTHERN OSCILLATION INDEX SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EL-NINO; INTRASEASONAL OSCILLATIONS; STATISTICAL-MODELS; GLOBAL ATMOSPHERE; TIME-SERIES; TEMPERATURE; ATTRACTORS; HEMISPHERE; DYNAMICS; WEATHER AB Singular spectrum analysis (SSA), a variant of principal component analysis, is applied to a time series of the Southern Oscillation index (SOI). The analysis filters out variability unrelated to the Southern Oscillation and separates the high-frequency, 2- to 3-year variability, including the quasi-biennial oscillation, from the lower-frequency 4- to 6-year El Nino cycle. The maximum entropy method (MEM) is applied to forecasting the prefiltered SOI. Prediction based on MEM-associated autoregressive models has useful skill for 30-36 months. A 1993-1994 La Nina event is predicted based on data through February 1992. C1 JET PROP LAB,PASADENA,CA 91109. UNIV CALIF LOS ANGELES,DEPT ATMOSPHER SCI,LOS ANGELES,CA 90024. UNIV CALIF LOS ANGELES,INST GEOPHYS & PLANETARY PHYS,LOS ANGELES,CA 90024. RP KEPPENNE, CL (reprint author), UNIV CALIF LOS ANGELES,CTR CLIMATE DYNAM,LOS ANGELES,CA 90024, USA. NR 52 TC 108 Z9 117 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1992 VL 97 IS D18 BP 20449 EP 20454 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KF923 UT WOS:A1992KF92300010 ER PT J AU LOPEZPUERTAS, M LOPEZVALVERDE, MA RINSLAND, CP AF LOPEZPUERTAS, M LOPEZVALVERDE, MA RINSLAND, CP TI ANALYSIS OF THE UPPER-ATMOSPHERE CO2(NU-2) VIBRATIONAL TEMPERATURES RETRIEVED FROM ATMOS SPACELAB 3 OBSERVATIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ATOMIC OXYGEN; LOWER THERMOSPHERE; ROCKET EXPERIMENT; CARBON-DIOXIDE; O-ATOMS; CO2; RELAXATION; MODEL; FLUORESCENCE; DEACTIVATION AB An analysis of the upper atmospheric (80-116 km) CO2(nu2) vibrational temperatures retrieved from atmospheric trace molecule spectroscopy (ATMOS) experiment Spacelab 3 spectra by using a nonlocal thermodynamic equilibrium (non-LTE) radiative transfer model is presented. Thermal collisions with atmospheric atomic oxygen keep this vibrational state very close to LTE up to around 100 km. Above this height the different deviations from LTE retrieved from ATMOS/Spacelab 3 spectra for the northern and southern hemispheres are explained in terms of this collisional process and in terms of the different kinetic temperature profiles measured at those locations. From these simultaneous observations of the kinetic and CO2(nu2) vibrational temperatures a deactivation rate of CO2(nu2) by (O(P))-P-3 has been derived which, considering the available climatologies of the concentration of this compound, leads to a rate coefficient value between 3 and 6 x 10(-12) cm3 s-1 and favors an independent or negative temperature dependence rate constant for the atmospheric temperature range. Cooling rates induced by the CO2 15-mum fundamental band in the upper mesosphere and lower thermosphere (80-116 km) were derived from the simultaneous kinetic temperature, CO2(mu2) vibrational temperature, and CO2 concentration, as measured by ATMOS/Spacelab 3, and found to be a factor of between 5 and 10 times larger than those generally accepted until very recently. C1 NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,HAMPTON,VA 23681. JET PROP LAB,PASADENA,CA 91109. RP LOPEZPUERTAS, M (reprint author), INST ASTROFIS ANDALUCIA,APPO 3004,E-18080 GRANADA,SPAIN. RI Lopez Puertas, Manuel/M-8219-2013 OI Lopez Puertas, Manuel/0000-0003-2941-7734 NR 49 TC 50 Z9 50 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1992 VL 97 IS D18 BP 20469 EP 20478 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KF923 UT WOS:A1992KF92300012 ER PT J AU RINSLAND, CP GUNSON, MR ZANDER, R LOPEZPUERTAS, M AF RINSLAND, CP GUNSON, MR ZANDER, R LOPEZPUERTAS, M TI MIDDLE AND UPPER-ATMOSPHERE PRESSURE-TEMPERATURE PROFILES AND THE ABUNDANCES OF CO2 AND CO IN THE UPPER-ATMOSPHERE FROM ATMOS SPACELAB 3 OBSERVATIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MOLECULE SPECTROSCOPY EXPERIMENT; FOURIER-TRANSFORM SPECTROSCOPY; SOLAR OCCULTATION SPECTRA; CARBON-DIOXIDE; LOWER THERMOSPHERE; VERTICAL-DISTRIBUTION; Q-BRANCH; STRATOSPHERE; INTENSITIES; PARAMETERS AB Based on a new approach, profiles of kinetic temperature and atmospheric pressure between 20 and 116 km altitude and C02 and CO volume mixing ratios between 70 and 116 km have been derived from the approximately 0.01-cm-1 resolution infrared solar occultation spectra recorded by the atmospheric trace molecular spectroscopy (ATMOS) Fourier transform spectrometer during the Spacelab 3 shuttle mission (April 29 to May 6, 1985). The physical model and CO2 profile results have been obtained from simultaneous multiscan least squares fitting of microwindows containing CO2 lines with temperature-dependent and temperature-independent intensities and N2 lines with temperature-independent intensities. The analysis included the retrieval of tangent height separations between spectra in the lower stratosphere, where independent information shows drifts of the sun tracker field of view on the solar disk. The physical model results are compared with climatological profiles, lower thermospheric temperatures computed with the MSISE-90 model, and other data. The CO2 retrievals indicate a nearly constant volume mixing ratio of 320 +/- 35 ppmv (parts per million, 10(-6), by volume) in the 70- to 90-km altitude region with a rapid decline in the CO2 volume mixing ratio beginning between 90 and 100 km; at 116 km the CO2 volume mixing ratio has declined to about 70 ppmv and is equal to the CO volume mixing ratio, which has been derived from fits to the (1-0) CO vibration-rotation band. The absorption by the nu2 + nu3 - nu2 band Of C02 has been analyzed to quantify nonlocal thermodynamic equilibrium (non-LTE) effects in the upper mesosphere and lower thermosphere. Up to an altitude of 100 km, the results indicate that the vibrational temperature of the nu2 state Of CO2 is within 5 K of the kinetic temperature. At higher altitudes, non-LTE effects are observable with the vibrational temperature of the nu2 state cooler than the kinetic temperature by 40 K (48-degrees-S) and 70 K (30-degrees-N) at 112 km. Above 112 km, lines of the nu2 + nu3 - nu2 band are too weak to be observed in the ATMOS spectra. C1 UNIV LIEGE,INST ASTROPHYS,B-4000 LIEGE,BELGIUM. INST ASTROFIS ANDALUCIA,E-18080 GRANADA,SPAIN. JET PROP LAB,PASADENA,CA 91109. RP RINSLAND, CP (reprint author), NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,MAIL CODE 401A,HAMPTON,VA 23681, USA. RI Lopez Puertas, Manuel/M-8219-2013 OI Lopez Puertas, Manuel/0000-0003-2941-7734 NR 55 TC 45 Z9 45 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1992 VL 97 IS D18 BP 20479 EP 20495 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KF923 UT WOS:A1992KF92300013 ER PT J AU EMERY, CA HABERLE, RM ACKERMAN, TP AF EMERY, CA HABERLE, RM ACKERMAN, TP TI A ONE-DIMENSIONAL MODELING STUDY OF CARBONACEOUS HAZE EFFECTS ON THE SPRINGTIME ARCTIC ENVIRONMENT SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIATION; AEROSOLS; ICE AB A one-dimensional three-component numerical model of the Arctic environment is developed to study the effect of Arctic haze on the surface energy balance. The model represents an improvement over earlier studies in that it accounts for the transfer of infrared as well as solar radiation through the atmosphere, turbulent mixing within the boundary layer, and heat conduction through snow-capped rea ice. In a control simulation, the model is used to calculate the steady state response of the springtime ocean-ice-atmosphere system to the presence of an airborne carbonaceous aerosol with an idealized (but realistic) vertical distribution representative of spring. Additional simulations are then carried out to examine the sensitivity of the response to humidity and surface albedo. In general, the results indicate that surface temperatures increase when haze is present, provided the relative humidity through the column does not change. Except in our control simulation, the increase is due to an increase in the absorbed radiation at the surface. This result is consistent with previous studies which indicated that the increased infrared emission to the surface would more than compensate for the haze-induced reduction in solar radiation at the surface. As in previous studies, the increase in infrared emission is due to the increase in atmospheric temperatures because of the absorption of solar radiation by the haze, and the increase in atmospheric emissivity because of the greater amount of atmospheric water vapor. The latter follows from the assumption that the relative humidity does not change. However, in the present study the change in the net radiation at the surface is small such that the magnitude of surface warming is also small (several degrees Kelvin or less). Indeed, in the control simulation the absorbed radiation at the surface decreases and the warming is actually brought about by an increase in the sensible heat flux. Furthermore, if the specific humidity rather than relative humidity is assumed constant, then surface temperatures decrease rather than increase. These results suggest that haze-induced surface temperature changes in the Arctic are difficult to determine, both in sign and magnitude, and that the Arctic environment is less sensitive than previously assumed. C1 SAN JOSE STATE UNIV,DEPT METEOROL,SAN JOSE,CA 95192. NASA,AMES RES CTR,DIV SPACE SCI,MOFFETT FIELD,CA 94035. PENN STATE UNIV,DEPT METEOROL,UNIV PK,PA 16802. NR 28 TC 8 Z9 8 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1992 VL 97 IS D18 BP 20599 EP 20613 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KF923 UT WOS:A1992KF92300022 ER PT J AU GOORVITCH, D GOLDMAN, A DOTHE, H TIPPING, RH CHACKERIAN, C AF GOORVITCH, D GOLDMAN, A DOTHE, H TIPPING, RH CHACKERIAN, C TI HYDROXYL X-2(II) PURE ROTATIONAL TRANSITIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SPECTRAL-LINE PARAMETERS; SOLAR OXYGEN ABUNDANCE; OH; PROBABILITIES; BANDS AB We present a list of frequencies, term values, Einstein A values, and assignments for the pure rotational transitions of the X2PI state of the OH molecule. This list includes transitions from 3 to 2015 cm-1 for DELTAupsilon = 0, upsilon'' = 0 - 4, and J'' = 0.5 - 49.5. The A values were computed using recent advances in calculating wave functions for a coupled system and an experimentally derived electric dipole moment function (Nelson et al. 1990) which exhibits curvature. C1 UNIV DENVER,DEPT PHYS,DENVER,CO 80210. YAP ANALYT INC,LEXINGTON,MA. UNIV ALABAMA,DEPT PHYS & ASTRON,TUSCALOOSA,AL 35401. NASA,AMES RES CTR,DIV EARTH SYST SCI,MOFFETT FIELD,CA 94035. RP GOORVITCH, D (reprint author), NASA,AMES RES CTR,DIV SPACE SCI,MOFFETT FIELD,CA 94035, USA. NR 10 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1992 VL 97 IS D18 BP 20771 EP 20786 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KF923 UT WOS:A1992KF92300032 ER PT J AU PICKETT, HM PETERSON, DB MARGOLIS, JS AF PICKETT, HM PETERSON, DB MARGOLIS, JS TI ABSOLUTE ABSORPTION OF OZONE IN THE MIDINFRARED SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID LINE STRENGTHS; REGION; N2O AB The absolute absorption of ozone in the midinfrared has been measured relative to 253.7-nm ultraviolet absorption to an accuracy of 1 % ming a Bruker Fourier transform spectrometer. These new results agree with previous measurements by diode laser measurements after the latter are corrected for more recent infrared calculations and ultraviolet cross sections. They also agree with a determination based on refractive index measurements in the infrared. RP PICKETT, HM (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 16 TC 28 Z9 28 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1992 VL 97 IS D18 BP 20787 EP 20793 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KF923 UT WOS:A1992KF92300033 ER PT J AU MARTIN, JML LEE, TJ AF MARTIN, JML LEE, TJ TI ACCURATE ABINITIO QUARTIC FORCE-FIELDS FOR BORANE AND BEH2 SO CHEMICAL PHYSICS LETTERS LA English DT Article ID GAUSSIAN-BASIS SETS; QUADRATIC CONFIGURATION-INTERACTION; ROTATIONAL PARTITION-FUNCTIONS; ELECTRON CORRELATION; VIBRATIONAL FREQUENCIES; HYDROGEN ADSORPTION; TRIPLE EXCITATIONS; ENERGIES; BERYLLIUM; MOLECULES AB The quartic force fields of BH3 and BeH2 have been computed ab initio using an augmented coupled cluster (CCSD(T)) method and basis sets of spdf and spdfg quality. For BH3, the computed spectroscopic constants are in very good agreement with recent experimental data, and definitively confirm misassignments in some older work, in agreement with recent ab initio studies. Using the computed spectroscopic constants, the rovibrational partition function for both molecules has been constructed using a modified direct numerical summation algorithm, and JANAF-style thermochemical tables are presented. C1 LIMBURGS UNIV CENTRUM,DEPT SBG,B-3590 DIEPENBEEK,BELGIUM. UNIV INSTELLING ANTWERP,INST MAT SCI,DEPT CHEM,B-2610 WILRIJK,BELGIUM. RP MARTIN, JML (reprint author), NASA,AMES RES CTR,MAIL STOP RTC-230-3,MOFFETT FIELD,CA 94035, USA. RI Lee, Timothy/K-2838-2012; Martin, Jan/A-7457-2008 OI Martin, Jan/0000-0002-0005-5074 NR 47 TC 60 Z9 60 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 18 PY 1992 VL 200 IS 5 BP 502 EP 510 DI 10.1016/0009-2614(92)80082-M PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KC216 UT WOS:A1992KC21600012 ER PT J AU RICH, DH GEORGE, T PIKE, WT MASERJIAN, J GRUNTHANER, FJ LARSSON, A AF RICH, DH GEORGE, T PIKE, WT MASERJIAN, J GRUNTHANER, FJ LARSSON, A TI CATHODOLUMINESCENCE AND TRANSMISSION ELECTRON-MICROSCOPY STUDY OF DARK LINE DEFECTS IN THICK IN0.2GA0.8AS GAAS MULTIPLE QUANTUM-WELLS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MISFIT DISLOCATIONS; PHOTOLUMINESCENCE; HETEROSTRUCTURES; RECOMBINATION; SUPERLATTICES; EPITAXY; GROWTH; STRAIN AB The spatial distribution of the long-wavelength luminescence in thick In0.2Ga0.8As/GaAs multiple quantum wells (MQWs) has been investigated using cathodoluminescence (CL) imaging and spectroscopy. The CL spectra show defect-induced broad bands between 1000 less than or similar to lambda less than or similar to 1600 nm. These bands exhibit spatial variations which correlate with the dark line defects (DLDs) observed in the lambda=950 nm exciton luminescence imaging. Transmission electron microscopy showed that [110]-oriented misfit dislocations occur primarily at the substrate-to-MQW and GaAs capping layer-to-MQW interfaces. The large spatial variation of the luminescence intensities indicates that the DLDs observed in CL images are caused by the presence of nonradiative recombination centers occurring in the MQW region located between the interface misfit dislocations. This study provides new information describing the origin and nature of DLDs and differs from previous models which have regarded the electronic nature of dislocation cores as the primary mechanism for inducing DLD radiative contrast in luminescence imaging of strained InGaAs/GaAs. C1 JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109. CHALMERS UNIV TECHNOL,DEPT OPTOELECTR & ELECT MEASUREMENTS,S-41296 GOTHENBURG,SWEDEN. RP RICH, DH (reprint author), UNIV SO CALIF,DEPT MAT SCI & ENGN,PHOTON MAT & DEVICES LAB,LOS ANGELES,CA 90089, USA. RI Larsson, Anders/P-7275-2015 OI Larsson, Anders/0000-0002-0912-7695 NR 27 TC 20 Z9 20 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1992 VL 72 IS 12 BP 5834 EP 5839 DI 10.1063/1.351939 PG 6 WC Physics, Applied SC Physics GA KC850 UT WOS:A1992KC85000044 ER PT J AU GARZOLI, SL GARRAFFO, Z PODESTA, G BROWN, O AF GARZOLI, SL GARRAFFO, Z PODESTA, G BROWN, O TI ANALYSIS OF A GENERAL-CIRCULATION MODEL PRODUCT .1. FRONTAL SYSTEMS IN THE BRAZIL MALVINAS AND KUROSHIO OYASHIO REGIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID OCEAN; SIMULATION; EXTENSION; CURRENTS; EDDIES AB In the present paper (part 1 of 2), the product of the Semtner and Chervin general circulation model (GCM) is compared with available observations in the frontal areas of the Brazil/Malvinas and the Kuroshio/Oyashio confluences. The dimensionality of the systems studied is reduced by using the empirical orthogonal functions (EOF) and frontal density methods. The two sets of data utilized to validate the model are the sea surface temperature (SST) from the satellite observations and temperature fields product from the GCM at levels 1 (12.5 m), 2 (37.5 m) and 6 (160 m). Comparisons are made between the dominant empirical modes and the locus of maximum probability for observations and model product. The model reproduces intense thermal fronts at the surface and in the upper layers. In the upper layer (level 1) they are induced by the internal dynamics of the model and not by the restoring of the model to climatology alone. The variability of these fronts is less pronounced in the model than in the observations. The dominant period in the observations is annual with contributions of semiannual and high frequency oscillations. In the model, the dominant variability is also annual at all analyzed levels. A semiannual oscillation contributed to a lower degree and is related to eddies that, in the model, have an annual and semiannual periodicity. For the regions examined, the location of the fronts are reproduced in the model within differences of 4-degrees to 5-degrees with observations. In the Brazil/Malvinas region, the Confluence front is reproduced approximately 4-degrees towards the west of the observed front. This appears to be due to the resolution of the model that, in a 0.5-degrees x 0.5-degrees grid, does not resolve the sharp slope at the edge of the Argentine continental shelf The maximum southward penetration of the warm tongue of Brazil waters occurs in the model approximately 4-degrees towards die north. This is related to the fact that, in the model, the Malvinas transport doubles the one derived from the observations. This might be due to the effect of a large modeled transport for the Circumpolar Current or, again, to a poor resolution of the topography. In the Kuroshio area, the Oyashio front, which in observations is more pronounced at the surface than in the lower layers, is well reproduced in the surface temperature field. On the contrary, the Kuroshio front, mom intense in the lower layers but still marked in the satellite observations, is visible in the model only below 160 m. The front is not present in the surface temperature field but, as a consequence of the thermal wind balance, an intense eastward flow at the location of the Kuroshio Extension is observed in the model velocity field. When compared with the observations, the location of the Extension is shifted approximately 5-degrees towards the south. This indicates a shift in latitude between the modeled and observed latitude of separation. The resolution-of the model is marginal to reproduce the process of eddy formation, but large scale eddies are observed in the model in both analyzed areas. They are generated as a pinch of the main flow with an annual and semiannual periodicity. We conclude that some of the differences between model and observations, like the differences found in the locations of the fronts, and the diminished variability, will decrease with a higher resolution. C1 NASA,GODDARD INST SPACE STUDIES,NEW YORK,NY 10025. UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149. RP GARZOLI, SL (reprint author), COLUMBIA UNIV,LAMONT DOHERTY GEOL OBSERV,PALISADES,NY 10964, USA. RI Garzoli, Silvia/A-3556-2010; Brown, Otis/C-7188-2015 OI Garzoli, Silvia/0000-0003-3553-2253; Brown, Otis/0000-0003-3111-1507 NR 26 TC 17 Z9 17 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD DEC 15 PY 1992 VL 97 IS C12 BP 20117 EP 20138 DI 10.1029/92JC02222 PG 22 WC Oceanography SC Oceanography GA KE656 UT WOS:A1992KE65600003 ER PT J AU GARRAFFO, Z GARZOLI, SL HAXBY, W OLSON, D AF GARRAFFO, Z GARZOLI, SL HAXBY, W OLSON, D TI ANALYSIS OF A GENERAL-CIRCULATION MODEL .2. DISTRIBUTION OF KINETIC-ENERGY IN THE SOUTH-ATLANTIC AND KUROSHIO OYASHIO SYSTEMS SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID EDDY ENERGY; OCEAN; DRIFTERS; WATER AB The energy of the model transient eddies at 37.5 m is compared with Geosat altimeter observations, for the South Atlantic Ocean and for the Kuroshio system. The model shows areas of transient motions overlapping the ones obtained from Geosat altimeter data. For the South Atlantic Ocean, the modeled eddy kinetic energy is smaller than the one observed with Geosat, by a factor of 3 for area average on the whole South Atlantic region, and by a factor of 4 for its western boundary. On the Agulhas system, transient eddy activity develops in the region where the Agulhas current retroflects. In the western South Atlantic, the modeled eddy activity is concentrated on the Confluence front; observed variability along a more extended region following the topography is not resolved in the model. For the Kuroshio region, the energy level of the modeled transient motions is comparable with Geosat observations, but the model eddy activity is more concentrated in the Kuroshio Current and not in the Kuroshio extension. The observations show the opposite. For the South Atlantic Ocean, a comparison is also done between model eddy kinetic energy (defined as including standing and transient eddy contributions) with values obtained from surface drifters. The analysis shows differences in the western boundary, and good agreement across the South Atlantic Ocean between 35-degrees-S and 45-degrees-S. In this formulation, the model mean energy level is smaller than the observed with drifters from the First GARP Global Experiment; differences might be due to an overestimation in the values obtained with the drifters. C1 COLUMBIA UNIV,LAMONT DOHERTY GEOL OBSERV,PALISADES,NY 10964. UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149. RP GARRAFFO, Z (reprint author), NASA,GODDARD INST SPACE STUDIES,COLUMBIA UNIV,NEW YORK,NY 10025, USA. RI Garzoli, Silvia/A-3556-2010 OI Garzoli, Silvia/0000-0003-3553-2253 NR 16 TC 10 Z9 10 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD DEC 15 PY 1992 VL 97 IS C12 BP 20139 EP 20153 DI 10.1029/92JC01395 PG 15 WC Oceanography SC Oceanography GA KE656 UT WOS:A1992KE65600004 ER PT J AU PERIGAUD, C DELECLUSE, P AF PERIGAUD, C DELECLUSE, P TI ANNUAL SEA-LEVEL VARIATIONS IN THE SOUTHERN TROPICAL INDIAN-OCEAN FROM GEOSAT AND SHALLOW-WATER SIMULATIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SURFACE CURRENT; ATLANTIC-OCEAN; ROSSBY WAVES; MODEL; OSCILLATIONS; CALIFORNIA; ALTIMETRY; MONSOON; KELVIN AB Sea level variations in the Indian Ocean north of 20-degrees-S are analyzed from Geosat satellite altimeter data in 1987-1988. These observed variations are compared with numerical simulations from a reduced-gravity model forced by observed winds over the same period. The first complex empirical orthogonal function of observed and simulated variations is an annual signal. For this signal, observations and simulations are highly correlated in both time and space. Off-equatorial sea level variations propagate westward and poleward as Rossby waves. The strongest annual variations occur in the southeastern tropical Indian Ocean. The maximum amplitude (approximately 12 cm) is located at about 90-degrees-E, 12-degrees-S, although the wind stress curl is weak there and east of it. The signal propagates from the eastern boundary to the southwest across almost all the basin. C1 UNIV PARIS 06,OCEANOGR DYNAM & CLIMATOL LAB,F-75252 PARIS 5,FRANCE. RP PERIGAUD, C (reprint author), JET PROP LAB,MAIL STOP 300-323,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 32 TC 98 Z9 98 U1 2 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD DEC 15 PY 1992 VL 97 IS C12 BP 20169 EP 20178 DI 10.1029/92JC01961 PG 10 WC Oceanography SC Oceanography GA KE656 UT WOS:A1992KE65600006 ER PT J AU HAKKINEN, S MELLOR, GL AF HAKKINEN, S MELLOR, GL TI MODELING THE SEASONAL VARIABILITY OF A COUPLED ARCTIC ICE-OCEAN SYSTEM SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SEA ICE; NUMERICAL-SIMULATION; SURFACE ALBEDO; COVER; CIRCULATION; WATER; BASIN; HEAT AB Results from modeling studies of the ice-ocean system in the Arctic Basin and in the Norwegian-Greenland-Barents seas are presented. We used a three-dimensional coupled ice-ocean model developed at Princeton University. The ocean model applies the primitive equations and a second moment turbulence closure for turbulent mixing. The snow-ice model uses a three-level thermodynamic scheme which resembles Semtner's (1976a) model. Our conclusions based on the seasonal simulations are as follows. (1) Using monthly climatological surface heat flux and wind stress, the seasonal variability of the ice cover is quite realistic in that the thickest ice is located north of Greenland and the average ice thickness is about 3 m. The largest deviation between the simulated and observed ice cover is in the Greenland Sea where oceanic conditions determine the ice edge. Basically, the monthly climatological forcing does not result in strong enough mixing to bring sufficient heat from the deep ocean to keep the central Greenland Sea gyre ice free. The results improve for both the ice cover and ocean by invoking daily wind forcing for which we first chose year 1987. In the ocean model, the large mixing events associated with storm passages are resolved, and as a result, the overall oceanic structure in the Greenland Sea appears to be more realistic. However, no deep convection takes place in the model during 1987 which is likely the result of diminished storm activity in the northern part of the Greenland Sea. The ice thickness field appears to be very anomalous 1987, so an experiment with 1986 daily wind forcing was also done, which resulted in an ice thickness field similar to some reported from other ice models. (2) Both monthly and daily surface forcing result in a similar behavior of the Atlantic waters in the Arctic Basin. The Atlantic waters circulate at about the observed level, between 400 and 600 m. The survival of the Atlantic waters in the basin depends strongly on the heat loss through the ice cover, and it appears that too much heat is lost on the Eurasian side through the ice because the simulated Atlantic waters are too cool by about 0.2-0.5-degrees-C. (3) For the monthly climatology case, a large amount of cold and salty water enters the Eurasia Basin from the Kara and Laptev seas area and finds its way toward the Canada Basin. This water mass appears to result from ice formation in the Kara and Laptev seas. When applying the daily forcing, this deep salinity maximum disappears due to increased mixing on the shelves. Nevertheless, this suggests a mechanism within the Arctic Ocean as to why the deep Canada Basin is much saltier than the Eurasia Basin. C1 PRINCETON UNIV,PRINCETON,NJ 08544. RP HAKKINEN, S (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HYDROSPHER SCI LAB,CODE 971,GREENBELT,MD 20771, USA. RI Hakkinen, Sirpa/E-1461-2012 NR 56 TC 90 Z9 93 U1 1 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD DEC 15 PY 1992 VL 97 IS C12 BP 20285 EP 20304 DI 10.1029/92JC02037 PG 20 WC Oceanography SC Oceanography GA KE656 UT WOS:A1992KE65600014 ER PT J AU WADHAMS, P TUCKER, WB KRABILL, WB SWIFT, RN COMISO, JC DAVIS, NR AF WADHAMS, P TUCKER, WB KRABILL, WB SWIFT, RN COMISO, JC DAVIS, NR TI RELATIONSHIP BETWEEN SEA ICE FREEBOARD AND DRAFT IN THE ARCTIC BASIN, AND IMPLICATIONS FOR ICE THICKNESS MONITORING SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CLASSIFICATION; SUBMARINE; SONAR AB We have confirmed our earlier finding that the probability density function (pdf) of ice freeboard in the Arctic Ocean can be converted to a pdf of ice draft by applying a simple coordinate transformation based on the measured mean draft and mean elevation. This applies in each of six 50-km sections (north of Greenland) of joint airborne laser and submarine sonar profile obtained along nearly coincident tracks from the Arctic Basin north of Greenland and tested for this study. Detailed differences in the shape of the pdf can be explained on the basis of snow load and can, in principle, be compensated by the use of-a more sophisticated freeboard-dependent transformation. The measured ''density ratio'' R (actually mean draft/mean elevation ratio) for each section was found to be consistent over all sections tested, despite differences in the ice regime, indicating that a single value of R might be used for measurements done in this season of the year. The mean value [R] from all six sections is 7.89; on the assumption that all six values are drawn from the same population, the standard deviation is 0.55 for a single 50-km section, and thus 0.22 for 300 km of track. In attempting to infer ice draft from laser-measured freeboard, we would therefore expect an accuracy of about +/- 28 cm in 50 km of track (if mean draft is about 4 m) and about +/- 11 cm in 300 km of track; these accuracies are compatible with the resolution of predictions from numerical models. A simple model for the variability of R with season and with mean ice thickness gives results in reasonable agreement with observations. They show that although there is a large seasonal variability due to snow load, there is a stable period from November to April when the variability is chiefly dependent on the mean ice thickness alone. Thus, in principle, R can be mapped over the Arctic Ocean as a basis for interpreting survey data. Better field data are needed on the seasonal and spatial variability of three key quantities: area-averaged snow load, mean density of first-year and multiyear ice (including the effect of ridging with these two ice regimes), and density of near-surface water. C1 NASA,GODDARD SPACE FLIGHT CTR,WALLOPS FLIGHT FACIL,HYDROSPHER,WALLOPS ISL,VA. NASA,GODDARD SPACE FLIGHT CTR,EG&G WASHINGTON ANALYT,WALLOPS FLIGHT FACIL,WALLOPS ISL,VA. USA,CORPS ENGN,COLD REGIONS RES & ENGN LAB,HANOVER,NH 03755. NASA,GODDARD SPACE FLIGHT CTR,HYDROSPHER PROC LAB,GREENBELT,MD 20771. RP WADHAMS, P (reprint author), UNIV CAMBRIDGE,SCOTT POLAR RES INST,LENSFIELD RD,CAMBRIDGE CB2 1ER,ENGLAND. NR 41 TC 55 Z9 55 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD DEC 15 PY 1992 VL 97 IS C12 BP 20325 EP 20334 DI 10.1029/92JC02014 PG 10 WC Oceanography SC Oceanography GA KE656 UT WOS:A1992KE65600017 ER PT J AU BHATT, H DONALDSON, KY HASSELMAN, DPH BHATT, RT AF BHATT, H DONALDSON, KY HASSELMAN, DPH BHATT, RT TI EFFECT OF HIPING ON THE EFFECTIVE THERMAL-CONDUCTIVITY DIFFUSIVITY AND THE INTERFACIAL THERMAL CONDUCTANCE OF UNIAXIAL SIC FIBER-REINFORCED RBSN SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID PYROLYTIC-GRAPHITE; COMPOSITES; RESISTANCE; BARRIER AB Hot isostatic pressing (HIPing) was found to increase the thermal diffusivity/conductivity of uniaxial silicon carbide fibre-reinforced reaction-bonded silicon nitride (RBSN) matrix composites, as the result of the densification of the matrix, the increase in the grain size of the silicon carbide and the improved thermal contact between the fibres and the matrix. Transverse to the fibre direction the thermal diffusivity/conductivity was found to be a function of the surrounding gaseous atmosphere due to the access of the gas phase to the fibre matrix interface, which was facilitated by the existence of an interfacial gap due to the thermal expansion mismatch between the fibres and the matrix. The interfacial conductance was found to exhibit a strong positive temperature dependence as the result of the closure of the interfacial gap with increasing temperature. C1 NASA,LEWIS RES CTR,DIV MAT,CERAM BRANCH,CLEVELAND,OH 44135. RP BHATT, H (reprint author), VIRGINIA POLYTECH INST & STATE UNIV,DEPT MAT ENGN,BLACKSBURG,VA 24061, USA. NR 27 TC 35 Z9 35 U1 2 U2 7 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD DEC 15 PY 1992 VL 27 IS 24 BP 6653 EP 6661 DI 10.1007/BF01165950 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA KD452 UT WOS:A1992KD45200015 ER PT J AU OSULLIVAN, D YOUNG, RE AF OSULLIVAN, D YOUNG, RE TI MODELING THE QUASI-BIENNIAL OSCILLATIONS EFFECT ON THE WINTER STRATOSPHERIC CIRCULATION SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID NORTHERN-HEMISPHERE WINTER; STRATOSPHERIC WARMINGS; INTERANNUAL VARIABILITY; ANTARCTIC OZONE; MODULATION; QBO AB The influence of the equatorial quasi-biennial oscillation (QBO) on the winter middle atmosphere is modeled with a mechanistic global primitive equation model. The model's polar vortex evolution is sensitive to the lower stratosphere's tropical winds, with the polar vortex becoming more (less) disturbed as the lower stratospheric winds are more easterly (westerly). This agrees with the observed relationship between wintertime polar circulation strength and the phase of the QBO in the lower stratosphere. In these experiments it is the extratropical planetary Rossby waves that provide the tropical-extratropical coupling mechanism- More easterly tropical winds in the lower stratosphere act to confine the extratropical Rossby waves farther north and closer to the vortex at the QBO altitudes, weakening the vortex relative to the case of westerly QBO phase. While the QBO winds occur in the lower stratosphere, the anomaly in the polar vortex strength is strongest at higher levels. C1 NASA,AMES RES CTR,DIV SPACE SCI,MOFFETT FIELD,CA 94035. RP OSULLIVAN, D (reprint author), NORTHWEST RES ASSOCIATES,POB 3027,BELLEVUE,WA 98009, USA. OI O'Sullivan, Daniel/0000-0001-9104-5703 NR 20 TC 59 Z9 59 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD DEC 15 PY 1992 VL 49 IS 24 BP 2437 EP 2448 DI 10.1175/1520-0469(1992)049<2437:MTQBOE>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KG493 UT WOS:A1992KG49300006 ER PT J AU HARLAFTIS, ET NAYLOR, T HASSALL, BJM CHARLES, PA SONNEBORN, G BAILEY, J AF HARLAFTIS, ET NAYLOR, T HASSALL, BJM CHARLES, PA SONNEBORN, G BAILEY, J TI UV SPECTROSCOPY OF Z CHAMAELEONTIS .2. THE 1988 JANUARY NORMAL OUTBURST SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE BINARIES-CLOSE; STARS-INDIVIDUAL-Z CHA; NOVAE, CATACLYSMIC VARIABLES; ULTRAVIOLET-STARS ID HIGH-SPEED PHOTOMETRY; NOVA OY-CARINAE; DWARF NOVA; ACCRETION DISKS; VW HYDRI; CATACLYSMIC VARIABLES; INFRARED LIGHT; SU UMA; Z-CHA; SUPEROUTBURST AB We present IUE observations of the 1988 January normal outburst of Z Cha and compare it with the 1987 April superoutburst (Paper I). The C IV lambda1549, Si IV lambda1397 and N V lambda1240 lines are approximately 40 per cent weaker than in superoutburst and are all partially eclipsed, by 10-30 per cent, which is similar to the situation during super-outburst. The spectra are bluer than in superoutburst, indicating a less extensive vertical-disc structure during normal outburst. The most dramatic difference from superoutburst is that the outburst continuum flux shows < 10 per cent orbital variation away from eclipse, implying that there is no 'cool' bulge on the disc to occult the brighter inner disc periodically. During outburst, the total observed luminosity of Z Cha is two orders of magnitude less than in VW Hyi. We discuss the implications for the outburst mechanism in the two types of outburst. Simultaneous IR observations during the normal outburst reveal the secondary star. Assuming that the secondary is not heated, the disc has brightened by a factor of seven from its quiescent level, and now contributes 75 per cent of the total IR flux, compared to less-than-or-equal-to 30 per cent during quiescence. C1 DEPT ASTROPHYS,NUCL PHYS LAB,OXFORD OX1 3RH,ENGLAND. UNIV CAMBRIDGE,INST ASTRON,CAMBRIDGE CB3 0HA,ENGLAND. ROYAL GREENWICH OBSERV,CAMBRIDGE CB3 0EZ,ENGLAND. NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. ANGLO AUSTRALIAN OBSERV,EPPING,NSW 2121,AUSTRALIA. RP HARLAFTIS, ET (reprint author), ROYAL GREENWICH OBSERY,APARTADO 321,SANTA CRUZ PALMA 38780,SPAIN. RI Sonneborn, George/D-5255-2012; Naylor, Tim /A-9465-2015 NR 36 TC 10 Z9 10 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD DEC 15 PY 1992 VL 259 IS 4 BP 593 EP 603 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KC269 UT WOS:A1992KC26900001 ER PT J AU HOLMAN, R HSU, S VACHASPATI, T WATKINS, R AF HOLMAN, R HSU, S VACHASPATI, T WATKINS, R TI METASTABLE COSMIC STRINGS IN REALISTIC MODELS SO PHYSICAL REVIEW D LA English DT Article ID CHARGED DARK MATTER; SUPERCONDUCTING STRINGS; TOPOLOGY; DYNAMICS; SPRINGS AB We investigate the stability of the electroweak Z string at high temperatures. Our results show that while finite-temperature corrections can improve the stability of the Z string, their effect is not strong enough to stabilize the Z string in the standard electroweak model. Consequently, the Z string will be unstable even under the conditions present during the electroweak phase transition. We then consider phenomenologically viable models based on the gauge group SU(2)L X SU(2)R X U(1)B - L and show that metastable strings exist and are stable to small perturbations for a large region of the parameter space for these models. We also show that these strings are superconducting with bosonic charge carriers. The string superconductivity may be able to stabilize segments and loops against dynamical contraction. Possible implications of these strings for cosmology are discussed. C1 HARVARD UNIV,LYMAN LAB PHYS,CAMBRIDGE,MA 02138. TUFTS UNIV,DEPT PHYS & ASTRON,TUFTS INST COSMOL,MEDFORD,MA 02155. UNIV CHICAGO,ENRICO FERMI INST,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. FERMI NATL ACCELERATOR LAB,NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. RP HOLMAN, R (reprint author), CARNEGIE MELLON UNIV,DEPT PHYS,PITTSBURGH,PA 15213, USA. NR 37 TC 20 Z9 20 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1992 VL 46 IS 12 BP 5352 EP 5359 DI 10.1103/PhysRevD.46.5352 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KE697 UT WOS:A1992KE69700014 ER PT J AU SHAHIDSALESS, B AF SHAHIDSALESS, B TI LOCAL GRAVITOMAGNETIC PERTURBATIONS OF THE LUNAR ORBIT SO PHYSICAL REVIEW D LA English DT Article ID FRAMES AB Using the metric in the local inertial frame of the Earth, we calculate relativistic effects on the lunar orbit with the synodic month period. It is shown that such perturbations arise entirely from the gravitomagnetic components of the local metric which exist because of the relative motion of the Sun with respect to the Earth. In the case of general relativity, the net perturbation has an amplitude of 3 cm for the lunar range. RP SHAHIDSALESS, B (reprint author), JET PROP LAB,CODE 301-150,PASADENA,CA 91109, USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1992 VL 46 IS 12 BP 5404 EP 5406 DI 10.1103/PhysRevD.46.5404 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KE697 UT WOS:A1992KE69700021 ER PT J AU ALBRECHT, A AF ALBRECHT, A TI INVESTIGATING DECOHERENCE IN A SIMPLE SYSTEM SO PHYSICAL REVIEW D LA English DT Article ID QUANTUM BROWNIAN-MOTION; INFLATIONARY UNIVERSE; LOGICAL REFORMULATION; WAVE PACKET; MECHANICS; PERTURBATIONS; DYNAMICS; FLUCTUATIONS; TRANSITION; COSMOLOGY AB I present the results of some simple calculations designed to study the loss of quantum coherence. The relevant physical issues are briefly reviewed, and then a very simple ''toy'' model is analyzed. Exact solutions are found using numerical techniques. The type of decoherence exhibited by the model can be changed by varying a coupling strength. I study the system from two points of view. One, the Schmidt paths approach, is closely related to the conventional approach of studying decoherence by checking the form of the density matrix. The consistent histories approach is also used, and the relationship between the two approaches is explored. C1 NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. NR 47 TC 52 Z9 52 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1992 VL 46 IS 12 BP 5504 EP 5520 DI 10.1103/PhysRevD.46.5504 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KE697 UT WOS:A1992KE69700034 ER PT J AU RAJ, SV FREED, AD AF RAJ, SV FREED, AD TI EFFECT OF STRAIN AND STRESS ON THE RELATIVE DIMENSIONS OF THE HARD AND SOFT REGIONS IN CREPT NACL SINGLE-CRYSTALS SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID CREEP SUBSTRUCTURE; HIGH-TEMPERATURE; METALS RP RAJ, SV (reprint author), NASA,LEWIS RES CTR,CLEVELAND,OH 44135, USA. OI Freed, Alan/0000-0002-3492-0628 NR 19 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD DEC 15 PY 1992 VL 27 IS 12 BP 1741 EP 1746 DI 10.1016/0956-716X(92)90012-4 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA KA975 UT WOS:A1992KA97500012 ER PT J AU NOEBE, RD BEHBEHANI, MK AF NOEBE, RD BEHBEHANI, MK TI THE EFFECT OF MICROALLOYING ADDITIONS ON THE TENSILE PROPERTIES OF POLYCRYSTALLINE NIAL SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID DUCTILITY; FRACTURE; BRITTLE RP NOEBE, RD (reprint author), NASA,LEWIS RES CTR,MS 493,CLEVELAND,OH 44135, USA. NR 18 TC 40 Z9 40 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD DEC 15 PY 1992 VL 27 IS 12 BP 1795 EP 1800 DI 10.1016/0956-716X(92)90022-7 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA KA975 UT WOS:A1992KA97500022 ER PT J AU CLARK, REH CSANAK, G ABDALLAH, J TRAJMAR, S AF CLARK, REH CSANAK, G ABDALLAH, J TRAJMAR, S TI DIFFERENTIAL CROSS-SECTIONS FOR ELECTRON-SCATTERING BY EXCITED BA (...6S6P1P1) ATOMS SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID PUMPED BARIUM VAPOR; IMPACT EXCITATION AB Differential electron scattering cross sections for excitation and de-excitation of Ba (... 6s6p 1P1) excited atoms were calculated at 30 eV impact energy in the unitarized distorted wave approximations using multiconfiguration wavefunctions. The results are compared to available experimental data. It is found that theory and experiment agree quite well as far as the shapes of the differential cross section curves are concerned. For some transitions, even the cross section magnitudes are in agreement, but for others, only order of magnitude agreement is found. Further experimental studies are needed to get a more accurate assessment of the situation. C1 JET PROP LAB,PASADENA,CA 91109. RP CLARK, REH (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 24 TC 6 Z9 6 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 14 PY 1992 VL 25 IS 23 BP 5233 EP 5244 DI 10.1088/0953-4075/25/23/024 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA KE313 UT WOS:A1992KE31300024 ER PT J AU MAN, KF TRAJMAR, S MCCONKEY, JW RATLIFF, JM KHAKOO, M AF MAN, KF TRAJMAR, S MCCONKEY, JW RATLIFF, JM KHAKOO, M TI EXCITATION OF ANTHRACENE (C14H10) BY ELECTRON-IMPACT SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; SPECTROSCOPY; RESONANCE; SPECTRUM; STATES; BANDS; DUST AB Electron-impact, energy-loss spectra of anthracene were obtained in the 12 to 100 eV impact energy range at angles ranging from 5-degrees to 40-degrees. From these spectra energy level information, relative electron-impact excitation probabilities and relative optical f values have been derived. Cross sections for 250-525 nm band emission have been measured over an electron-impact energy range from threshold to 60 eV. Many processes, both direct and indirect, are observed to contribute to the excitation. The results are compared with those obtained using naphthalene targets. C1 CALIF STATE UNIV FULLERTON,FULLERTON,CA 92634. UNIV WINDSOR,DEPT PHYS,WINDSOR N9B 3P4,ONTARIO,CANADA. RP MAN, KF (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 37 TC 4 Z9 4 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 14 PY 1992 VL 25 IS 23 BP 5245 EP 5256 DI 10.1088/0953-4075/25/23/025 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA KE313 UT WOS:A1992KE31300025 ER PT J AU KOGUT, A SMOOT, GF BENNETT, CL WRIGHT, EL AYMON, J DEAMICI, G HINSHAW, G JACKSON, PD KAITA, E KEEGSTRA, P LINEWEAVER, C LOEWENSTEIN, K ROKKE, L TENORIO, L BOGGESS, NW CHENG, ES GULKIS, S HAUSER, MG JANSSEN, MA KELSALL, T MATHER, JC MEYER, S MOSELEY, SH MURDOCK, TL SHAFER, RA SILVERBERG, RF WEISS, R WILKINSON, DT AF KOGUT, A SMOOT, GF BENNETT, CL WRIGHT, EL AYMON, J DEAMICI, G HINSHAW, G JACKSON, PD KAITA, E KEEGSTRA, P LINEWEAVER, C LOEWENSTEIN, K ROKKE, L TENORIO, L BOGGESS, NW CHENG, ES GULKIS, S HAUSER, MG JANSSEN, MA KELSALL, T MATHER, JC MEYER, S MOSELEY, SH MURDOCK, TL SHAFER, RA SILVERBERG, RF WEISS, R WILKINSON, DT TI COBE DIFFERENTIAL MICROWAVE RADIOMETERS - PRELIMINARY SYSTEMATIC-ERROR ANALYSIS SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMIC MICROWAVE BACKGROUND; ARTIFICIAL SATELLITES, SPACE PROBES; METHODS, STATISTICAL AB The Differential Microwave Radiometers (DMR) instrument aboard the Cosmic Background Explorer (COBE) maps the full microwave sky in order to measure the large-angular-scale anisotropy of the cosmic microwave background radiation. Solar system foreground sources, instrumental effects, as well as data recovery and processing, can combine to create statistically significant artifacts in the analyzed data. We discuss the techniques available for the identification and subtraction of these effects from the DMR data and present preliminary limits on their magnitude in the DMR 1 yr maps (Smoot et al. 1992). The largest effect is the instrument response to the Earth's magnetic field, which contributes up to 375 muK to the raw data in the worst channel. Emission from the Earth is weak (less than 47 muK in the raw data at 95% confidence). Residual uncertainties in the best DMR sky maps, after correcting-the raw data for systematic effects, are less than 6 muK for the pixel rms variation, less than 3 muK for the rms quadrupole amplitude of a spherical harmonic expansion, and less than 30 muK2 for the correlation function (all limits 95% confidence level). These limits are a factor of 5-40 lower than the level of anisotropy in the microwave background detected in the 1 yr DMR sky maps: 30 +/- 5 muK rms, 13 +/- 4 muK quadrupole, and 1194 +/- 499 muK2 for the correlation function (Smoot et al. 1992; Bennett et al. 1992b; Wright et al. 1992). C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. UNIV CALIF LOS ANGELES,DEPT ASTRON,LOS ANGELES,CA 90024. HUGHES STX CORP,LANHAM,MD 20706. JET PROP LAB,PASADENA,CA 91109. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. GEN RES CORP,DANVERS,MA 01923. PRINCETON UNIV,DEPT PHYS,PRINCETON,NJ 08544. RP KOGUT, A (reprint author), NASA,GODDARD SPACE FLIGHT CTR,UNIV SPACE RES ASSOC,CODE 6859,GREENBELT,MD 20771, USA. RI Moseley, Harvey/D-5069-2012; Kogut, Alan/D-6293-2012; Rokke, Laurie/I-5642-2015 OI Rokke, Laurie/0000-0002-5696-7240 NR 16 TC 52 Z9 52 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP 1 EP 18 DI 10.1086/172033 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB243 UT WOS:A1992KB24300001 ER PT J AU VANCURA, O BLAIR, WP LONG, KS DAVIDSEN, AF BOWERS, CW DIXON, WV DURRANCE, ST FELDMAN, PD FERGUSON, HC HENRY, RC KIMBLE, RA KRISS, GA KRUK, JW MOOS, HW AF VANCURA, O BLAIR, WP LONG, KS DAVIDSEN, AF BOWERS, CW DIXON, WV DURRANCE, ST FELDMAN, PD FERGUSON, HC HENRY, RC KIMBLE, RA KRISS, GA KRUK, JW MOOS, HW TI FAR-ULTRAVIOLET OBSERVATIONS OF THE SUPERNOVA REMNANT N49 USING THE HOPKINS ULTRAVIOLET TELESCOPE SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM, INDIVIDUAL (N49); MAGELLANIC CLOUDS; SHOCK WAVES; SUPERNOVA REMNANTS; ULTRAVIOLET, INTERSTELLAR ID LARGE MAGELLANIC CLOUD; H-II REGIONS; CYGNUS LOOP; SHOCK-WAVES; EXTINCTION; EMISSION; MODELS; RAY AB Using the Hopkins Ultraviolet Telescope on the Astro-1 space shuttle mission in 1990 December, we have obtained a far-ultraviolet spectrum (912-1860 angstrom at 3.5 angstrom resolution) of a complex of bright filaments located in the eastern part of the supernova remnant N49 in the Large Magellanic Cloud. This is the first observation of an extragalactic supernova remnant that extends to the Lyman limit. We detect lines of O VI lambda1035, O IV] lambda1403, C IV lambda1550, and He II lambda1640. The O VI emission that we observe cannot originate in shocks with velocities less-than-or-equal-to 140 km s-1 which are responsible for the bulk of both the C IV and the optical line emission. Likewise, the main blast wave with a velocity approximately 730 km s-1 is unable to account for the brightness of O VI. Most of the O VI originates in optically faint, 190-270 km s-1 shocks, traversing clouds with densities of 20-40 cm-3. We expand upon earlier modeling of N49 IUE and optical spectra that assumed a distribution of shock velocities; including data from below Lyalpha, such models still describe the data well. C1 SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. UNIV CAMBRIDGE,OBSERV,INST ASTRON,CAMBRIDGE CB3 0HA,ENGLAND. NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. RP VANCURA, O (reprint author), JOHNS HOPKINS UNIV,CTR ASTROPHYS SCI,DEPT PHYS & ASTRON,34TH & CHARLES ST,BALTIMORE,MD 21218, USA. RI Kruk, Jeffrey/G-4047-2012 NR 28 TC 14 Z9 14 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP 220 EP 225 DI 10.1086/172054 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB243 UT WOS:A1992KB24300022 ER PT J AU CHERCHNEFF, I BARKER, JR TIELENS, AGGM AF CHERCHNEFF, I BARKER, JR TIELENS, AGGM TI POLYCYCLIC AROMATIC HYDROCARBON FORMATION IN CARBON-RICH STELLAR ENVELOPES SO ASTROPHYSICAL JOURNAL LA English DT Article DE CIRCUMSTELLAR MATTER; ISM, JETS AND OUTFLOWS; MOLECULAR PROCESSES; STARS, CARBON; STARS, MASS LOSS ID CIRCUMSTELLAR DUST SHELLS; EMISSION FEATURES; FLAMES; GRAINS; SOOT; STAR; RECOMBINATION; DECOMPOSITION; ACETYLENE; MECHANISM AB The formation of polycyclic aromatic hydrocarbon (PAH) molecules in carbon-rich stellar outflows is modeled with a detailed chemical kinetic scheme applied to stellar envelope profiles of gas density and temperature. These envelope models include the average effects of strong periodic shocks at the inner envelope boundary and radiation pressure acceleration of the stellar outflow. The chemical kinetic scheme is based on the work of Frenklach & Feigelson with revisions and extentions from recent combustion literature on soot formation. The model explicitly includes organic molecules, free radicals, and aromatics up to the size of cyclopenta[cd]pyrene (C18H12). Chemical concentration profiles were calculated for several envelope models by integrating the coupled continuity equations that include spherically expanding flows from an inner boundary at the shock formation radius, where the chemical composition is assumed to be at thermal equilibrium. The influence of the "inverse greenhouse" effect experienced by small PAHs has been investigated and shown to increase the PAH yield by many orders of magnitudes. A detailed examination of the various chemical kinetic routes towards closure of the first aromatic ring, the bottleneck in any soot formation scheme, shows that the route through propargyl radicals (C3H3) could be an important channel to produce benzene. It is pointed out that the combustion community has not reached a consensus regarding chemical kinetic schemes for soot formation, and thus future work on PAH formation in stellar envelopes may require further revisions to the kinetic scheme. The PAH formation yields are found to be extremely sensitive to gas density and temperature, and they are much smaller than values inferred from the observed dust content of late-type carbon-rich stellar envelopes. Assuming the chemical kinetic scheme is substantially correct, it is therefore unlikely that aromatic molecules are generated in the stellar outflow itself. Instead, PAH formation might be initiated very close to the photosphere. One possible mechanism is that PAHs may form and accumulate in gas parcels subjected to oscillatory quasi-ballistic trajectories induced by shocks close to the photosphere. C1 UNIV MICHIGAN, DEPT ATMOSPHER OCEAN & SPACE SCI, ANN ARBOR, MI 48109 USA. NASA, AMES RES CTR, DIV BEHAV BIOL, MOFFETT FIELD, CA 94035 USA. RI Barker, John/F-5904-2012 OI Barker, John/0000-0001-9248-2470 NR 56 TC 228 Z9 228 U1 1 U2 19 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP 269 EP 287 DI 10.1086/172059 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB243 UT WOS:A1992KB24300027 ER PT J AU MOORE, MH HUDSON, RL AF MOORE, MH HUDSON, RL TI FAR-INFRARED SPECTRAL STUDIES OF PHASE-CHANGES IN WATER ICE INDUCED BY PROTON IRRADIATION SO ASTROPHYSICAL JOURNAL LA English DT Article DE DUST, EXTINCTION; MOLECULAR DATA ID IRAS 09371+1212; DIFFRACTION PATTERN; ELECTRON-MICROSCOPY; D2O ICE; H2O ICE; ABSORPTION AB Far-infrared spectra from 20 mum (500 cm-1) to 100 mum (100 cm-1) of water ice have been measured over the temperature range of 13-155 K. Amorphous and crystalline water ice are easily identified in far-infrared spectra since amorphous ice has one broad absorption peak near 45 mum (220 cm-1) and crystalline has absorptions near 44 mum (229 cm-1) and 62 mum (162 cm-1). We have observed radiation-induced phase changes in both amorphous and crystalline ice. Crystalline ice converts to an amorphous phase when irradiated at temperatures between 77 and 13 K. The conversion rate increases as the temperature is decreased and the converted fraction is dose dependent. No radiation-induced changes are detected in amorphous ice between 125 and 36 K. However, far-infrared spectra of proton-irradiated ices near 13 K show interconversion between the amorphous and crystalline ice phases beginning at doses near 2 eV molecule-1 and continuing cyclically with increased dose. A quadrupole mass spectrometer was used to detect H-2, H2O, and 02 releases associated with the cyclic phase conversions. Radiation-induced phase changes in these two forms will be discussed in relation to interstellar ices, and ices in comets. C1 ECKERD COLL,DEPT CHEM,ST PETERSBURG,FL 33733. RP MOORE, MH (reprint author), NASA,GODDARD SPACE FLIGHT CTR,EXTRATERR PHYS LAB,ASTROCHEM BRANCH,GREENBELT,MD 20771, USA. RI Hudson, Reggie/E-2335-2012 NR 44 TC 103 Z9 103 U1 1 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP 353 EP 360 DI 10.1086/172065 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB243 UT WOS:A1992KB24300033 ER PT J AU MAZUR, JE MASON, GM KLECKER, B MCGUIRE, RE AF MAZUR, JE MASON, GM KLECKER, B MCGUIRE, RE TI THE ENERGY-SPECTRA OF SOLAR-FLARE HYDROGEN, HELIUM, OXYGEN, AND IRON - EVIDENCE FOR STOCHASTIC ACCELERATION SO ASTROPHYSICAL JOURNAL LA English DT Article DE ACCELERATION OF PARTICLES; SUN, FLARES; SUN, PARTICLE EMISSION ID SHOCK ACCELERATION; PARTICLE EVENTS; INTERPLANETARY SHOCKS; NUCLEONIC ABUNDANCES; TEMPORAL VARIATIONS; TURBULENCE; NUCLEAR; IONS AB The time-integrated differential energy spectra of H, He, O, and Fe measured in 10 large flare events observed at 1 AU over the energy range of 0.3-80 MeV nucleon-1 showed consistent patterns in their spectral shapes: particles with larger mean mass-to-charge ratios were generally less abundant at higher energies. Combined measurements from the University of Maryland/Max-Planck-Institut sensors on the ISEE 1 spacecraft and Goddard Space Flight Center instrumentation on IMP 8 extended the energy range beyond that measured with any single instrument. A steady state model of stochastic particle acceleration with rigidity-dependent diffusion coefficients fit the spectra best; spectra representative of diffusive shock acceleration also described the spectra of some events with the same number of free parameters, but often fell off faster in energy above 30 MeV per nucleon than the observations. The two model predictions differed most at energies near 0.1 MeV per nucleon, below the lowest energies observed in this study. The stochastic model quantitatively described the observed spectral ordering with less efficient acceleration of species with larger mean mass-to-charge ratios. C1 UNIV MARYLAND,INST PHYS SCI & TECHNOL,COLL PK,MD 20742. MAX PLANCK INST EXTRATERRESTR PHYS,W-8046 GARCHING,GERMANY. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP MAZUR, JE (reprint author), UNIV MARYLAND,DEPT PHYS,COLL PK,MD 20742, USA. OI Klecker, Berndt/0000-0001-8337-5120 NR 28 TC 69 Z9 70 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP 398 EP & DI 10.1086/172071 PN 1 PG 0 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB243 UT WOS:A1992KB24300039 ER PT J AU KASTNER, SO BHATIA, AK AF KASTNER, SO BHATIA, AK TI PHOTON ESCAPE PROBABILITIES FROM RESOLVED SOURCES - APPLICATION TO SOLAR C-III LIMB EMISSION SO ASTROPHYSICAL JOURNAL LA English DT Article DE ATOMIC PROCESSES; RADIATIVE TRANSFER; SUN, UV RADIATION ID APPROXIMATE CALCULATION; TRANSITION ZONE; LINE RATIOS; QUIET SUN; CHROMOSPHERE; SPECTRUM; OPACITY; MODELS; CORONA AB Monodirectional effective escape probabilities, involving line-of-sight-integrated escape factors, are calculated for the highly anisotropic source represented by C III emission at the solar limb as a concrete example of the application of such probabilities. Predicted intensity variations of C III lines with limb distance are obtained using a spherical shell model, showing several interesting features which may be observable with appropriate instruments. Among these are expected enhancements of extreme ultraviolet lines at 884.5 and 1308.7 angstrom, and local limb-brightening and limb-darkening effects in optically thick lines, which may provide sensitive constraints on the solar C III emission distribution. Comparisons are made with available observations. C1 NASA, GODDARD SPACE FLIGHT CTR, ASTRON & SOLAR PHYS LAB, GREENBELT, MD 20771 USA. RP MATH SCI CONSULTANTS INC, 1-A RIDGE RD, GREENBELT, MD 20770 USA. NR 39 TC 12 Z9 12 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP 416 EP 431 DI 10.1086/172073 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB243 UT WOS:A1992KB24300041 ER PT J AU MATTOX, JR BERTSCH, DL FICHTEL, CE HARTMAN, RC KNIFFEN, DA THOMPSON, DJ AF MATTOX, JR BERTSCH, DL FICHTEL, CE HARTMAN, RC KNIFFEN, DA THOMPSON, DJ TI SAS-2 OBSERVATION OF PULSED HIGH-ENERGY GAMMA-RADIATION FROM GEMINGA SO ASTROPHYSICAL JOURNAL LA English DT Article DE GAMMA-RAYS, OBSERVATIONS; PULSARS, INDIVIDUAL (GEMINGA) ID 1E 0630+178; PULSARS AB Following the detection of pulsed X-rays and gamma rays from Geminga, the 1972-1973 SAS 2 data which first revealed this source have been reanalyzed. The 237 ms periodicity is visible in those observations. The phase of the SAS 2 periodicity is consistent with that of COS B suggesting that the gamma-ray data allow an accounting for every revolution of the Geminga pulsar between 1972 and 1982. C1 HAMPDEN SYDNEY COLL,DEPT PHYS,HAMPDEN SYDNEY,VA 23943. RP MATTOX, JR (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 24 TC 35 Z9 35 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP L23 EP L26 DI 10.1086/186661 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB244 UT WOS:A1992KB24400007 ER PT J AU WEAVER, KA MUSHOTZKY, RF ARNAUD, KA SERLEMITSOS, PJ MARSHALL, FE PETRE, R JAHODA, KM BOLDT, EA HOLT, SS SWANK, J SZYMKOWIAK, AE KELLEY, R SMALE, AP DONE, C AF WEAVER, KA MUSHOTZKY, RF ARNAUD, KA SERLEMITSOS, PJ MARSHALL, FE PETRE, R JAHODA, KM BOLDT, EA HOLT, SS SWANK, J SZYMKOWIAK, AE KELLEY, R SMALE, AP DONE, C TI BROAD-BAND X-RAY TELESCOPE OBSERVATIONS OF NGC-4151 - IRON LINE DIAGNOSTICS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, INDIVIDUAL (NGC-4151); GALAXIES, NUCLEI; GALAXIES, SEYFERT ID ACTIVE GALACTIC NUCLEI; COLD MATTER; FLUORESCENCE; VARIABILITY; REFLECTION; DISK AB The Fe Kalpha emission line is a potentially powerful diagnostic tool in the X-ray spectra of AGNs, however, this feature has previously been observed with relatively poor spectral resolution. The Broad Band X-Ray Telescope (BBXRT) has provided us with the first high-quality, medium-resolution X-ray spectral data. We are able to constrain the width of the 6.4 keV Fe Kalpha line in NGC 4151 to be less than 160 eV FWHM (7,500 km s-1), in contrast with former measurements of the line width. Also, we have limited information on the shape of the line profile. In addition to the strong narrow Fe Kalpha feature, we detect weaker broad residuals between 5-8 keV. C1 UNIV MARYLAND,COLL PK,MD 20742. RP WEAVER, KA (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. RI Swank, Jean/F-2693-2012; Kelley, Richard/K-4474-2012; done, chris/D-4605-2016 OI done, chris/0000-0002-1065-7239 NR 19 TC 17 Z9 17 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1992 VL 401 IS 1 BP L11 EP L14 DI 10.1086/186658 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB244 UT WOS:A1992KB24400004 ER PT J AU SMITH, GD YOON, DY JAFFE, RL AF SMITH, GD YOON, DY JAFFE, RL TI CONFORMATIONS OF POLYMER MELTS BETWEEN PARALLEL SURFACES - COMPARISON OF THE SCHEUTJENS FLEER LATTICE THEORY WITH MONTE-CARLO SIMULATIONS SO MACROMOLECULES LA English DT Article ID MODEL; THERMODYNAMICS; INTERFACES; CHAINS AB Conformations of chains in polymer melts confined between parallel solid surfaces are examined by means of lattice Monte Carlo (MC) simulations and the Scheutjens-Fleer self-consistent-field (SCF) lattice theory for the purpose of comparing SCF predictions directly with simulation. The effects of surface-chain end interactions on conformational properties of the chains are investigated by considering nonadsorbing, weakly adsorbing, and strongly adsorbing chain ends. Quantitative agreement between MC simulations and SCF theory is found for segment and chain end density distributions and bond orientation profiles. The SCF theory reproduces major features of polymer conformations, as seen in the distributions of loops, tails, trains, and bridges, but quantitative comparisons show considerable differences which are attributed primarily to the reversible walk nature of the SCF theory. It was found that increasing the surface-chain end adsorption energy leads to the formation of more brushlike chain conformations, with more long tails and loops and fewer long train sequences. C1 IBM CORP,ALMADEN RES CTR,650 HARRY RD,SAN JOSE,CA 95120. ELORET INST,SUNNYVALE,CA 94087. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 12 TC 36 Z9 36 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 7 PY 1992 VL 25 IS 25 BP 7011 EP 7017 DI 10.1021/ma00051a044 PG 7 WC Polymer Science SC Polymer Science GA KB785 UT WOS:A1992KB78500044 ER PT J AU PHILLIPS, RW AF PHILLIPS, RW TI FREEDOM TO EXPLORE SO NATURE LA English DT Letter RP PHILLIPS, RW (reprint author), NASA,SPACE STN FREEDOM,WASHINGTON,DC 20546, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD DEC 3 PY 1992 VL 360 IS 6403 BP 404 EP 404 DI 10.1038/360404b0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KA797 UT WOS:A1992KA79700013 ER PT J AU RIND, D AF RIND, D TI ICE AGES - AN UPLIFTING EXPERIENCE SO NATURE LA English DT Editorial Material ID CLIMATE RP RIND, D (reprint author), GODDARD SPACE FLIGHT CTR,INST SPACE STUDIES,NEW YORK,NY 10023, USA. NR 9 TC 3 Z9 3 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD DEC 3 PY 1992 VL 360 IS 6403 BP 414 EP 415 DI 10.1038/360414a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KA797 UT WOS:A1992KA79700024 ER PT J AU AHRENS, TJ HARRIS, AW AF AHRENS, TJ HARRIS, AW TI DEFLECTION AND FRAGMENTATION OF NEAR-EARTH ASTEROIDS SO NATURE LA English DT Article ID CRATER AB The collision with Earth of near-Earth asteroids or comet nuclei poses a potential threat to mankind. Objects about 100 m in diameter could be diverted from an Earth-crossing trajectory by the impact of a rocket-launched mass, but for larger bodies nuclear explosions seem to be the only practical means of deflection. Fragmentation of the body by nuclear charges is less efficient or secure. C1 JET PROP LAB, PASADENA, CA 91109 USA. RP AHRENS, TJ (reprint author), CALTECH, LINDHURST LAB EXPTL GEOPHYS, SEISMOL LAB 252-21, PASADENA, CA 91125 USA. NR 24 TC 85 Z9 87 U1 1 U2 12 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD DEC 3 PY 1992 VL 360 IS 6403 BP 429 EP 433 DI 10.1038/360429a0 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KA797 UT WOS:A1992KA79700048 ER PT J AU DOYLE, RJ AF DOYLE, RJ TI NATIONAL-AERONAUTICS-AND-SPACE-ADMINISTRATION WORKSHOP ON MONITORING AND DIAGNOSIS SO AI MAGAZINE LA English DT Article AB The First National Aeronautics and Space Administration (NASA) Workshop on Monitoring and Diagnosis was held in Pasadena, California, from 15 to 17 January 1992. The workshop brought together individuals from NASA centers, academia, and aerospace who have a common interest in AI-based approaches to monitoring and diagnosis technology. The workshop was intended to promote familiarity, discussion, and collaboration among the research, development, and user communities. RP DOYLE, RJ (reprint author), JET PROP LAB,MS-525-3660,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC ARTIFICIAL INTELL PI MENLO PK PA 445 BURGESS DRIVE, MENLO PK, CA 94025-3496 SN 0738-4602 J9 AI MAG JI AI Mag. PD WIN PY 1992 VL 13 IS 4 BP 13 EP 16 PG 4 WC Computer Science, Artificial Intelligence SC Computer Science GA KD103 UT WOS:A1992KD10300001 ER PT J AU MONTEMERLO, MD AF MONTEMERLO, MD TI THE AI PROGRAM AT THE NATIONAL-AERONAUTICS-AND-SPACE-ADMINISTRATION - LESSONS LEARNED DURING THE 1ST 7 YEARS SO AI MAGAZINE LA English DT Article AB This article is a slightly modified version of an invited address that was given at the Eighth IEEE Conference on Artificial Intelligence for Applications in Monterey, California, on 2 March 1992. It describes the lessons learned in developing and implementing the Artificial Intelligence Research and Development Program at the National Aeronautics and Space Administration (NASA). In so doing, the article provides a historical perspective of the program in terms of the stages it went through as it matured. These stages are similar to the 'ages of artificial intelligence' that Pat Winston described a year before the NASA program was initiated. The final section of the article attempts to generalize some of the lessons learned during the first seven years of the NASA AI program into AI program management heuristics. RP MONTEMERLO, MD (reprint author), NASA,ARTIFICIAL INTELLIGENCE RES & DEV PROGRAM,WASHINGTON,DC 20546, USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSOC ARTIFICIAL INTELL PI MENLO PK PA 445 BURGESS DRIVE, MENLO PK, CA 94025-3496 SN 0738-4602 J9 AI MAG JI AI Mag. PD WIN PY 1992 VL 13 IS 4 BP 49 EP 61 PG 13 WC Computer Science, Artificial Intelligence SC Computer Science GA KD103 UT WOS:A1992KD10300004 ER PT J AU KNIGHT, DD BADEKAS, D HORSTMAN, CC SETTLES, GS AF KNIGHT, DD BADEKAS, D HORSTMAN, CC SETTLES, GS TI QUASICONICAL FLOWFIELD STRUCTURE OF THE 3-DIMENSIONAL SINGLE FIN INTERACTION SO AIAA JOURNAL LA English DT Article ID TURBULENT BOUNDARY-LAYER; SKIN-FRICTION MEASUREMENTS; SHOCK-WAVE; SHARP FIN; FLOW; EQUATIONS AB A series of conical and three-dimensional computations have been performed for the swept oblique shock wave/turbulent boundary-layer interaction generated by a 20-deg sharp fin at Mach 4 and Reynolds number Re(deltainfinity) = 2.18 x 10(5) based on (he incoming boundary-layer thickness delta(infinity). The Reynolds-averaged compressible Navier-Stokes equations are employed with turbulence incorporated using the Baldwin-Lomax and Jones-Launder models. The computed results are basically similar for both turbulence models and display general agreement with experimental data for surface pressure and surface now direction, although underestimating the size of the primary vortex. The computed three-dimensional flowfield displays quasiconical behavior of the surface pressure, surface flow direction, and flowfield contours of static pressure, density, and Mach number over the extent of the computational domain except for an inception region near the fin leading edge. The streamlines of the computed three-dimensional flowfield are qualitatively conical; however, the computed attachment streamline does not exhibit conical behavior within the computational domain. The surface skin friction is not conical. Most of the features of the quasiconical flowfield model of Settles et al. are observed in the computations, including the lambda shock, slip line, primary vortex, expansion region, and high-speed jet impingement. Certain features of the flowfield model are not observed in the computations, namely, a ''normal'' shock near the attachment line, transonic shocklets in the expansion region, and secondary separation. The absence of these features in the computation is believed to be indirectly attributable to limitations in the turbulence models. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. PENN STATE UNIV,DEPT MECH ENGN,UNIV PK,PA 16802. RUTGERS STATE UNIV,DEPT MECH & AEROSP ENGN,NEW BRUNSWICK,NJ 08903. PENN STATE UNIV,GAS DYNAM LAB,UNIV PK,PA 16802. RP KNIGHT, DD (reprint author), RUTGERS STATE UNIV,DEPT AEROSP & MECH ENGN,NEW BRUNSWICK,NJ 08903, USA. NR 47 TC 14 Z9 15 U1 0 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1992 VL 30 IS 12 BP 2809 EP 2816 DI 10.2514/3.48972 PG 8 WC Engineering, Aerospace SC Engineering GA KD413 UT WOS:A1992KD41300001 ER PT J AU CARAM, JM AHMED, A AF CARAM, JM AHMED, A TI DEVELOPMENT OF THE WAKE OF AN AIRFOIL WITH RIBLETS SO AIAA JOURNAL LA English DT Article AB TESTS were conducted on a NACA 0012 airfoil with riblets at a freestream Reynolds number of 2.5 x 10(5) in the Texas A&M University indraft wind tunnel. The riblets used in the investigation were of symmetric v-groove type with the heights of 0.0229, 0.076, and 0. 152 mm. Measurements of the mean velocity profiles, turbulence, and integral quantities in the near and intermediate wakes indicated that the growth of the wake of an airfoil with riblets was similar to that of a clean airfoil. It was also observed that even at a distance of 600 momentum thicknesses downstream of the trailing edge wake equilibrium had not been reached for any of the configurations tested; however, riblet effectiveness was indicated by a marked decrease in the level of maximum shear stress, especially for the 0.152 mm riblets. C1 TEXAS A&M UNIV SYST,DEPT AEROSP ENGN,COLL STN,TX 77843. NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. NR 10 TC 6 Z9 6 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1992 VL 30 IS 12 BP 2817 EP 2818 DI 10.2514/3.11623 PG 2 WC Engineering, Aerospace SC Engineering GA KD413 UT WOS:A1992KD41300002 ER PT J AU SUES, RH CHEN, HC CHAMIS, CC MURTHY, PLN AF SUES, RH CHEN, HC CHAMIS, CC MURTHY, PLN TI PROGRAMMING PROBABILISTIC STRUCTURAL-ANALYSIS FOR PARALLEL PROCESSING COMPUTERS SO AIAA JOURNAL LA English DT Article AB SIGNIFICANT advances have taken place in probabilistic structural analysis (PSA) over the last two decades. Much of this research has focused on basic theory development and the development of approximate analytic solution methods. Practical application of PSA methods has been hampered, however, by their computationally intense nature. Solutions of PSA problems require repeated analyses of structures that are often large and exhibit nonlinear and/or dynamic response behavior. PSA methods, however, are all inherently parallel and ideally suited to implementation on parallel processing computers. This synoptic1 summarizes the results of the first phase of research to develop a parallel processing system that can significantly reduce the computational times for large-scale PSA problems. Parallel processing improves the speed with which a computational task is done by breaking it into subtasks and executing as many as possible of these subtasks simultaneously. A summary of the principal ideas in parallel processing and a survey of currently available architecture appears in Sues et al.2 We identify here the multiple levels of parallelism in PSA, describe the development of a parallel stochastic finite element code, and present results of an example application. Although the example application achieved both excellent speedups and greater than 95% efficiency, we conclude that achieving massive parallelism will require overcoming limitations of current parallel architectures. New hardware/software strategies must be developed that keep large numbers of processors busy while minimizing memory requirements and interprocessor communication. Hence, we provide generic hardware and software recommendations for achieving large-scale parallel PSA implementation. C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. RP SUES, RH (reprint author), APPL RES ASSOCIATES INC,RALEIGH,NC 27165, USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1992 VL 30 IS 12 BP 2871 EP 2872 DI 10.2514/3.11631 PG 2 WC Engineering, Aerospace SC Engineering GA KD413 UT WOS:A1992KD41300010 ER PT J AU SRIDHARAN, S ZEGGANE, M STARNES, JH AF SRIDHARAN, S ZEGGANE, M STARNES, JH TI POSTBUCKLING RESPONSE OF STIFFENED COMPOSITE CYLINDRICAL-SHELLS SO AIAA JOURNAL LA English DT Article ID IMPERFECTION-SENSITIVITY; INFINITE STRIPS; PANELS AB The local buckling and the associated postbuckling response of stiffened composite shells are studied using an asymptotic approach. Both the classical (Kirchhoff) theory (CPT) and a first-order shear deformation theory (SDT) are employed in the study. SDT analysis was carried out using p-version type finite strips, whereas CPT analysis employed h-version based strips. Convergence studies confirm the superiority of the p-version approach. A panel width-to-thickness ratio of 50 was chosen to investigate the influence of shear deformation for stiffened and isolated panels fabricated out of isotropic and composite layered materials. The shear deformation effects were significant for composite stiffened shell panels with CPT giving a noticeably stiffer response. In comparison with isotropic shell panels, orthotropic layered panels buckle at lower nondimensional buckling loads but are appreciably less sensitive to imperfection, C1 NASA,LANGLEY RES CTR,AIRCRAFT STRUCT BRANCH,HAMPTON,VA 23665. RP SRIDHARAN, S (reprint author), WASHINGTON UNIV,DEPT MOLEC ENDOCRINOL,ST LOUIS,MO 63130, USA. NR 15 TC 9 Z9 9 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1992 VL 30 IS 12 BP 2897 EP 2905 DI 10.2514/3.11635 PG 9 WC Engineering, Aerospace SC Engineering GA KD413 UT WOS:A1992KD41300014 ER PT J AU SARAVANOS, DA PEREIRA, JM AF SARAVANOS, DA PEREIRA, JM TI EFFECTS OF INTERPLY DAMPING LAYERS ON THE DYNAMIC CHARACTERISTICS OF COMPOSITE PLATES SO AIAA JOURNAL LA English DT Article AB Integrated damping mechanics for composite plates with constrained interlaminar layers of polymer damping materials are developed. Discrete layer damping mechanics are presented for composite laminates with damping layers, in connection with a semianalytical method for predicting the modal damping in simply supported specialty composite plates. Correlations between predicted and measured response in graphite/epoxy plates illustrate the accuracy of the method. Additional application cases for graphite/epoxy plates of various laminations demonstrate the potential for higher damping then geometrically equivalent aluminum plates. The effects of aspect ratio, damping layer thickness, and fiber volume ratio on static and dynamic characteristics of the composite plate are also investigated. RP SARAVANOS, DA (reprint author), NASA,LEWIS RES CTR,21000 BROOKPARK,MS 49-8,CLEVELAND,OH 44135, USA. NR 19 TC 45 Z9 48 U1 0 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1992 VL 30 IS 12 BP 2906 EP 2913 DI 10.2514/3.11636 PG 8 WC Engineering, Aerospace SC Engineering GA KD413 UT WOS:A1992KD41300015 ER PT J AU CHU, CC MILMAN, MH AF CHU, CC MILMAN, MH TI EIGENVALUE ERROR ANALYSIS OF VISCOUSLY DAMPED STRUCTURES USING A RITZ REDUCTION METHOD SO AIAA JOURNAL LA English DT Article ID DYNAMIC ANALYSIS; VECTORS AB The efficient solution of the eigenvalue problem that results from inserting passive dampers with variable stiffness and damping coefficients into a structure is addressed. Eigenanalysis of reduced models obtained by retaining a number of normal modes augmented with Ritz vectors corresponding to the static solutions resulting from the load patterns introduced by the dampers has been empirically shown to yield excellent approximations to the full eigenvalue problem. An analysis of this technique in the case of a single damper is presented. A priori and a posteriori error estimates are generated and tested on numerical examples. Comparison theorems with modally truncated models and a Markov parameter matching reduced-order model are derived. These theorems corroborate the heuristic that residual flexibility methods improve low-frequency approximation of the system. The analysis leads to other techniques for eigenvalue approximation. Approximate closed-form solutions are derived that include a refinement to eigenvalue derivative methods for approximation. An efficient Newton scheme is also developed. A numerical example is presented demonstrating the effectiveness of each of these methods. RP CHU, CC (reprint author), JET PROP LAB,GUIDANCE & CONTROL SECT,TECH STAFF,MAIL STOP 198-326,PASADENA,CA 91109, USA. NR 19 TC 6 Z9 6 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1992 VL 30 IS 12 BP 2935 EP 2944 DI 10.2514/3.11640 PG 10 WC Engineering, Aerospace SC Engineering GA KD413 UT WOS:A1992KD41300019 ER PT J AU NEMETH, MP AF NEMETH, MP TI BUCKLING OF SYMMETRICALLY LAMINATED PLATES WITH COMPRESSION, SHEAR, AND INPLANE BENDING SO AIAA JOURNAL LA English DT Article ID COMPOSITE PLATES AB A parametric study of the buckling behavior of infinitely long symmetrically laminated anisotropic plates subjected to combined loadings is presented. The loading conditions considered are pure in-plane bending, transverse tension and compression, and shear. Results obtained using a special purpose analysis that is well suited for parametric studies are presented for clamped and simply supported plates. Moreover, results are presented for some common laminate constructions, and generic buckling design charts are presented for a wide range of useful nondimensional parameters. RP NEMETH, MP (reprint author), NASA,LANGLEY RES CTR,DIV STRUCT MECH,AIRCRAFT STRUCT BRANCH,MAIL STOP 190,HAMPTON,VA 23665, USA. NR 17 TC 16 Z9 16 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1992 VL 30 IS 12 BP 2959 EP 2965 DI 10.2514/3.11643 PG 7 WC Engineering, Aerospace SC Engineering GA KD413 UT WOS:A1992KD41300022 ER PT J AU VIKRAM, CS WITHEROW, WK TROLINGER, JD AF VIKRAM, CS WITHEROW, WK TROLINGER, JD TI DETERMINATION OF REFRACTIVE PROPERTIES OF FLUIDS FOR DUAL-WAVELENGTH INTERFEROMETRY SO APPLIED OPTICS LA English DT Article DE REFRACTIVE INDEX; CRYSTAL GROWTH; HOLOGRAPHY; DUAL-WAVELENGTH INTERFEROMETRY; TRIGLYCINE SULFATE; HEAT AND MASS TRANSFER; SPACE APPLICATIONS ID GROWTH AB Methods to calculate the refractive properties of solutions at different wavelengths are described by using experimental data at just two wavelengths. The properties are the refractive index and its gradients with temperature and concentration. Cauchy's equation is used to determine the refractive indices. The gradients versus temperature and concentration are then determined by using the Murphy-Alpert and the Lorentz-Lorenz equation, respectively. Finally, the particular case of a triglycine sulfate aqueous solution is considered as an example. The approach should provide the desired information for fringe analysis when dual-wavelength holographic or other interferometry is used for solving heat and mass transfer problems in fluids during crystal-growth experiments. C1 METROLASER,IRVINE,CA 92714. NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,SPACE SCI LAB,HUNTSVILLE,AL 35812. RP VIKRAM, CS (reprint author), UNIV ALABAMA,CTR APPL OPT,HUNTSVILLE,AL 35899, USA. NR 14 TC 8 Z9 8 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 1992 VL 31 IS 34 BP 7249 EP 7252 PG 4 WC Optics SC Optics GA JZ714 UT WOS:A1992JZ71400014 PM 20802590 ER PT J AU KENNISH, JM SHARPDAHL, JL CHAMBERS, KA THROWER, F RICE, SD AF KENNISH, JM SHARPDAHL, JL CHAMBERS, KA THROWER, F RICE, SD TI THE EFFECT OF A HERRING DIET ON LIPID-COMPOSITION, FATTY-ACID COMPOSITION, AND CHOLESTEROL LEVELS IN THE MUSCLE-TISSUE OF PEN-REARED CHINOOK SALMON (ONCORHYNCHUS-TSHAWYTSCHA) SO AQUACULTURE LA English DT Article ID RAINBOW-TROUT LIVER; FRESH-WATER FISH; THERMAL-ACCLIMATION; COHO SALMON; WILD FISH; GAIRDNERI; METABOLISM; BENEFITS; STRAINS; FLESH AB Two groups of chinook salmon were held in marine net-pens. The control group was fed a Biodiet commercial diet, and the study group was fed whole herring. Fish of both groups were sampled at the start of the study and monthly for 3 months. The herring diet had a significant influence on the dorsal muscle total lipid content which doubled in the first month compared to the controls. The n-3/n-6 ratio in the herring-fed fish increased by 28%, while in the control group it decreased by 57% during the study period. The change appears to be related to the difference in 18:2n-6 levels in the diets. Cholesterol levels of the herring-fed salmon were twice that of the salmon fed the commercial diet, but were still much lower than initial cholesterol levels. This study demonstrates, for the first time, that the nutritional quality of pen-reared chinook salmon can be improved shortly before marketing by modifying the diet. C1 NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,AUKE BAY LAB,JUNEAU,AK. RP KENNISH, JM (reprint author), UNIV ALASKA,DEPT CHEM PHYS,ANCHORAGE,AK 99508, USA. NR 32 TC 22 Z9 23 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD DEC PY 1992 VL 108 IS 3-4 BP 309 EP 322 DI 10.1016/0044-8486(92)90115-2 PG 14 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA KA817 UT WOS:A1992KA81700010 ER PT J AU LAI, KS JAWEED, MM SEESTEAD, R HERBISON, GJ DITUNNO, JF MCCULLY, K CHANCE, B AF LAI, KS JAWEED, MM SEESTEAD, R HERBISON, GJ DITUNNO, JF MCCULLY, K CHANCE, B TI CHANGES IN NERVE-CONDUCTION AND PI/PCR RATIO DURING DENERVATION-REINNERVATION OF THE GASTROCSOLEUS MUSCLES OF RATS SO ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION LA English DT Article DE DENERVATION; MUSCLE; NERVE CONDUCTION; PHOSPHORUS AND PHOSPHOCREATINE RATIO; REINNERVATION ID NUCLEAR MAGNETIC-RESONANCE; SKELETAL-MUSCLE; METABOLISM AB The purpose of this investigation was to study the changes in nerve conduction and phosphate metabolites of the gastrocsoleus muscles of rats during denervation-reinnervation. Sixteen male Sprague-Dawley rats underwent unilateral crush-denervation of the left sciatic nerves at the sciatic notch. Six rats were used for measurement of motor conduction latency and action potential amplitude of the gastrocsoleus muscle by stimulating the sciatic nerve at one, two and eight weeks after nerve crush. The other ten rats were designated for evaluation of the ratio of inorganic phosphorous (Pi) to phosphocreatine (PCr) by a P-31-phosphoenergetic spectrometer at two weeks and eight weeks after nerve crush. None of the sciatic nerves showed conduction to the gastrocsoleus at one or two weeks after nerve crush. At eight weeks postcrush, the motor conduction latency returned to within normal limits, whereas the action potential amplitude was only 55% of the normal. For the eight-week period of study, the Pi/PCr ratio of the normal control muscles ranged between 0.09 +/- 0.02 and 0.11 +/- 0.02 (mean +/- SD). The denervated muscles showed an increase of Pi/PCr ratio by 54% at two weeks postcrush, compared to the respective contralateral control sides. The ratios returned to the normal value by eight weeks postcrush. In summary, these data suggested that the metabolic recovery of the crush-denervated muscle followed the same pattern as the parameters of nerve conduction. C1 THOMAS JEFFERSON UNIV,DEPT REHABIL MED,PHILADELPHIA,PA 19107. UNIV PENN,DEPT BIOCHEM & BIOPHYS,PHILADELPHIA,PA 19104. NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. RP LAI, KS (reprint author), UMDNJ HOSP,DEPT PHYS MED & REHABIL,B239,150 BERGEN ST,NEWARK,NJ 07103, USA. NR 19 TC 14 Z9 15 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 SN 0003-9993 J9 ARCH PHYS MED REHAB JI Arch. Phys. Med. Rehabil. PD DEC PY 1992 VL 73 IS 12 BP 1155 EP 1159 PG 5 WC Rehabilitation; Sport Sciences SC Rehabilitation; Sport Sciences GA KC864 UT WOS:A1992KC86400008 PM 1463379 ER PT J AU MINTON, S JOHNSTON, MD PHILIPS, AB LAIRD, P AF MINTON, S JOHNSTON, MD PHILIPS, AB LAIRD, P TI MINIMIZING CONFLICTS - A HEURISTIC REPAIR METHOD FOR CONSTRAINT SATISFACTION AND SCHEDULING PROBLEMS SO ARTIFICIAL INTELLIGENCE LA English DT Article ID SEARCH TECHNIQUES; QUEENS PROBLEM; GRAPH; COLOR AB The paper describes a simple heuristic approach to solving large-scale constraint satisfaction and scheduling problems. In this approach one starts with an inconsistent assignment for a set of variables and searches through the space of possible repairs. The search can be guided by a value-ordering heuristic, the min-conflicts heuristic, that attempts to minimize the number of constraint violations after each step. The heuristic can be used with a variety of different search strategies. We demonstrate empirically that on the n-queens problem, a technique based on this approach performs orders of magnitude better than traditional backtracking techniques. We also describe a scheduling application where the approach has been used successfully. A theoretical analysis is presented both to explain why this method works well on certain types of problems and to predict when it is likely to be most effective. C1 SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. RP MINTON, S (reprint author), NASA,AMES RES CTR,STERLING FED SYST,AI RES BRANCH,MAIL STOP 2692,MOFFETT FIELD,CA 94035, USA. NR 45 TC 320 Z9 332 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0004-3702 J9 ARTIF INTELL JI Artif. Intell. PD DEC PY 1992 VL 58 IS 1-3 BP 161 EP 205 DI 10.1016/0004-3702(92)90007-K PG 45 WC Computer Science, Artificial Intelligence SC Computer Science GA JZ749 UT WOS:A1992JZ74900006 ER PT J AU ZWEBEN, M DAVIS, E DAUN, B DRASCHER, E DEALE, M ESKEY, M AF ZWEBEN, M DAVIS, E DAUN, B DRASCHER, E DEALE, M ESKEY, M TI LEARNING TO IMPROVE CONSTRAINT-BASED SCHEDULING SO ARTIFICIAL INTELLIGENCE LA English DT Article ID SEARCH AB This paper describes an application of an analytical learning technique, plausible explanation-based learning (PEBL), that dynamically acquires search control knowledge for a constraint-based scheduling system. In general, the computational efficiency of a scheduling system suffers due to resource contention among activities. Our system learns the general conditions under which chronic contention occurs and uses search control to avoid repeating mistakes. Because it is impossible to prove that a chronic contention will occur with only one example, traditional EBL techniques are insufficient. We extend classical EBL by adding an empirical component that creates search control rules only when the system pins enough confidence in the plausible explanations. This extension to EBL was driven by our observations about the behavior of our scheduling system when applied to the real-world problem of scheduling tasks for NASA Space Shuttle payload and ground processing. C1 NASA,AMES RES CTR,RECOM TECHNOL,MOFFETT FIELD,CA 94035. LOCKHEED SPACE OPERAT CO,TITUSVILLE,FL 32780. RP ZWEBEN, M (reprint author), NASA,AMES RES CTR,MS 2692,MOFFETT FIELD,CA 94035, USA. NR 43 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0004-3702 J9 ARTIF INTELL JI Artif. Intell. PD DEC PY 1992 VL 58 IS 1-3 BP 271 EP 296 DI 10.1016/0004-3702(92)90010-U PG 26 WC Computer Science, Artificial Intelligence SC Computer Science GA JZ749 UT WOS:A1992JZ74900009 ER PT J AU ARMSTRONG, JT HUMMEL, CA QUIRRENBACH, A BUSCHER, DF MOZURKEWICH, D VIVEKANAND, M SIMON, RS DENISON, CS JOHNSTON, KJ PAN, XP SHAO, M COLAVITA, MM AF ARMSTRONG, JT HUMMEL, CA QUIRRENBACH, A BUSCHER, DF MOZURKEWICH, D VIVEKANAND, M SIMON, RS DENISON, CS JOHNSTON, KJ PAN, XP SHAO, M COLAVITA, MM TI THE ORBIT OF PHI-CYGNI MEASURED WITH LONG-BASE-LINE OPTICAL INTERFEROMETRY - COMPONENT MASSES AND ABSOLUTE MAGNITUDES SO ASTRONOMICAL JOURNAL LA English DT Article ID STARS AB We present the orbit of the double-lined spectroscopic binary phi Cygni, the distance to the system, and the masses and absolute magnitudes of its components. The apparent orbit is based on our observations with the Mark III Optical Interferometer, the distance (80.8+/-1.8 pc) and component masses (2.54 +/-0.09 M. and 2.44+/-0.08 M., in agreement with the previous determination by McAlister [AJ, 101, 2207 (1982)]) are based on the Mark III data combined with a reinterpretation of the spectroscopic data of Rach & Herbig [ApJ, 133, 143 (1961)], and the absolute V magnitudes (0.77m+/-0.1m and 1.07m+/-0.1m) are derived from the distance, the cataloged integrated magnitude, and the magnitude difference from spectroscopic data. From a comparison of M(V) and (B-V) with the isochrones of Maeder & Meynet [A&AS 89, 451 (1991)], both components have undergone He ignition. C1 CALTECH,DEPT ASTRON,PASADENA,CA 91125. JET PROP LAB,PASADENA,CA 91109. USRA,WASHINGTON OFF CTR,WASHINGTON,DC 20024. RP ARMSTRONG, JT (reprint author), USNO,NRL,OPT INTERFEROMETER PROJECT,3450 & MASSACHUSETTS AVE NW,WASHINGTON,DC 20392, USA. NR 20 TC 27 Z9 27 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 1992 VL 104 IS 6 BP 2217 EP 2223 DI 10.1086/116396 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JZ639 UT WOS:A1992JZ63900016 ER PT J AU JACOBSON, RA AF JACOBSON, RA TI ASTROGRAPHIC OBSERVATIONS OF THE MAJOR URANIAN SATELLITES FROM VOYAGER-2 SO ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES LA English DT Article DE ARIEL; ASTROMETRY; MIRANDA; OBERON; SATELLITES OF URANUS; TITANIA; UMBRIEL; AND VOYAGER-2 ID DEIMOS ASTROMETRIC OBSERVATIONS; PHOBOS AB This article provides the reduced astrographic observations of the major Uranian satellites derived from star-satellite imaging data acquired by the Voyager 2 spacecraft. The data set contains 445 sets of spacecraft-centered right ascension and declination observations and includes all of the observations used in Voyager encounter operations. The conversion process from imaging to astrographic observations was identical to that used for the Neptunian satellites (Jacobson 1991). The effect of using the astrographic rather than imaging form in ephemeris improvement is evaluated. RP JACOBSON, RA (reprint author), JET PROP LAB,301-150,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 11 TC 8 Z9 8 U1 0 U2 1 PU EDITIONS PHYSIQUE PI LES ULIS CEDEX PA Z I DE COURTABOEUF AVE 7 AV DU HOGGAR, BP 112, 91944 LES ULIS CEDEX, FRANCE SN 0365-0138 J9 ASTRON ASTROPHYS SUP JI Astron. Astrophys. Suppl. Ser. PD DEC PY 1992 VL 96 IS 3 BP 549 EP 563 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KG982 UT WOS:A1992KG98200009 ER PT J AU ARENDT, RG DWEK, E LEISAWITZ, D AF ARENDT, RG DWEK, E LEISAWITZ, D TI INFRARED-EMISSION FROM X-RAY AND OPTICALLY EMITTING REGIONS IN THE CYGNUS LOOP SUPERNOVA REMNANT SO ASTROPHYSICAL JOURNAL LA English DT Article DE DUST, EXTINCTION; INFRARED, INTERSTELLAR, CONTINUUM; ISM, INDIVIDUAL (CYGNUS LOOP); SUPERNOVA REMNANTS ID EINSTEIN OBSERVATIONS; TEMPERATURE-FLUCTUATIONS; INTERSTELLAR GRAINS; IRAS OBSERVATIONS; SHOCK-WAVE; HOT GAS; DUST; IC-443; PRECURSORS; DYNAMICS AB We present a new technique for analyzing the infrared (IR) emission of a supernova remnant (SNR) and apply it to the Cygnus Loop. The technique consists of a decomposition of the IR emission from the remnant (in all four IRAS bands) into two distinct emission components. The first component is spatially correlated with the X-ray emission from the remnant and arises from collisionally heated dust in the shocked gas. The second component is spatially correlated with the optical filaments and arises from dust which is radiatively or collisionally heated within the filaments, and from IR lines emitted by the shocked gas. The decomposition allows us to determine the characteristics of the dust, examine evidence for grain processing through the shock, 'constrain various remnant parameters, and demonstrate how the morphology of the environment determines the IR emission from the remnant. C1 NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771. PENN STATE UNIV,DEPT ASTRON,UNIV PK,PA 16802. RP ARENDT, RG (reprint author), APPL RES CORP,CDAC,CTR COMMERCE 2,ROOM 100,7601 ORA GLEN DR,GREENBELT,MD 20770, USA. NR 53 TC 27 Z9 27 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1992 VL 400 IS 2 BP 562 EP & DI 10.1086/172019 PN 1 PG 0 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JY438 UT WOS:A1992JY43800016 ER PT J AU HOLMAN, GD BENKA, SG AF HOLMAN, GD BENKA, SG TI A HYBRID THERMAL NONTHERMAL MODEL FOR THE ENERGETIC EMISSIONS FROM SOLAR-FLARES SO ASTROPHYSICAL JOURNAL LA English DT Article DE ACCELERATION OF PARTICLES; PLASMAS; SUN, FLARES; SUN, X-RAYS ID RUNAWAY ELECTRONS; X-RAY; ACCELERATION AB We present an alternative interpretation of the high-resolution solar flare spectra obtained in 1981 by Lin et al. In our interpretation electron heating and acceleration are simultaneous and physically linked, rather than heating being a secondary effect of particle acceleration. We show that the observed properties of solar flare X-ray emission can in general be explained through the Joule heating and electric field acceleration of runaway electrons in current channels. We have fitted a hybrid thermal/nonthermal electron distribution, consisting of hot isothermal electrons with a nonthermal tail of runaway electrons, to representative spectra obtained by Lin et al. The hybrid model relaxes the electron number and energy flux requirements for the hard X-ray emission over those of a purely nonthermal model. The low-energy "cutoff" to the nonthermal part of the X-ray spectrum is determined by the critical velocity in the electron distribution above which runaway acceleration occurs. We relate the fit parameters to the physical properties (such as the electric field strength in the current channels of the acceleration region. C1 USN, RES LAB, WASHINGTON, DC 20375 USA. RP NASA, GODDARD SPACE FLIGHT CTR, ASTRON & SOLAR PHYS LAB, GREENBELT, MD 20771 USA. RI Holman, Gordon/C-9548-2012 NR 25 TC 50 Z9 53 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1992 VL 400 IS 2 BP L79 EP L82 DI 10.1086/186654 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JY439 UT WOS:A1992JY43900010 ER PT J AU SREEKUMAR, P BERTSCH, DL DINGUS, BL FICHTEL, CE HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA LIN, YC MATTOX, JR MAYERHASSELWANDER, HA MICHELSON, PF VONMONTIGNY, C NOLAN, PL PINKAU, K SCHNEID, EJ THOMPSON, DJ AF SREEKUMAR, P BERTSCH, DL DINGUS, BL FICHTEL, CE HARTMAN, RC HUNTER, SD KANBACH, G KNIFFEN, DA LIN, YC MATTOX, JR MAYERHASSELWANDER, HA MICHELSON, PF VONMONTIGNY, C NOLAN, PL PINKAU, K SCHNEID, EJ THOMPSON, DJ TI OBSERVATIONS OF THE LARGE MAGELLANIC CLOUD IN HIGH-ENERGY GAMMA-RAYS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GAMMA RAYS, OBSERVATIONS; MAGELLANIC CLOUDS; COSMIC RAYS ID RADIATION; TELESCOPE; GALAXY AB The Large Magellanic Cloud (LMC) provides a valuable site to study gamma-ray production, intensity, and distribution in an external galaxy. Using 4 weeks of data from the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma Ray Observatory, high-energy gamma-ray emission was detected for the first time from the LMC region. These gamma rays are believed to be produced primarily through the interaction of cosmic rays with interstellar matter. Hence, combined with a knowledge of the interstellar matter distribution, they can provide a direct measure of the cosmic-ray density in an external galaxy. The results obtained from EGRET observations indicate that the level of cosmic rays in the LMC is comparable to that in our Galaxy. The integrated flux above 100 MeV is (1.9 +/- 0.4) x 10(-7) photons (cm2 s)-1. The measured flux suggests a cosmic-ray density level consistent with that expected from a quasi-stable equilibrium model. This is the first detection of a normal galaxy outside the Milk Wa in high-energy gamma rays. C1 NASA,GODDARD SPACE FLIGHT CTR,USRA RES ASSOC,GREENBELT,MD 20770. MAX PLANCK INST EXTRATERRESTR PHYS,W-8046 GARCHING,GERMANY. HAMPDEN SYDNEY COLL,HAMPDEN SYDNEY,VA 23943. STANFORD UNIV,HANSEN EXPTL PHYS LAB,STANFORD,CA 94305. NASA,GODDARD SPACE FLIGHT CTR,COMP SCI CORP,COMPTON OBSERV,CTR SCI SUPPORT,CODE 6681,GREENBELT,MD 20771. GRUMMAN AEROSP CORP,BETHPAGE,NY 11714. RP SREEKUMAR, P (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 662,GREENBELT,MD 20771, USA. RI Nolan, Patrick/A-5582-2009; Hunter, Stanley/D-2942-2012; Thompson, David/D-2939-2012 OI Thompson, David/0000-0001-5217-9135 NR 27 TC 82 Z9 82 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1992 VL 400 IS 2 BP L67 EP L70 DI 10.1086/186651 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JY439 UT WOS:A1992JY43900007 ER PT J AU REALMUTO, VJ HON, K KAHLE, AB ABBOTT, EA PIERI, DC AF REALMUTO, VJ HON, K KAHLE, AB ABBOTT, EA PIERI, DC TI MULTISPECTRAL THERMAL INFRARED MAPPING OF THE 1 OCTOBER 1988 KUPAIANAHA FLOW FIELD, KILAUEA VOLCANO, HAWAII SO BULLETIN OF VOLCANOLOGY LA English DT Article AB Multispectral thermal infrared radiance measurements of the Kupaianaha flow field were acquired with the NASA airborne Thermal Infrared Multispectral Scanner (TIMS) on the morning of 1 October 1988. The TIMS data were used to map both the temperature and emissivity of the surface of the flow field. The temperature map depicted the underground storage and transport of lava. The presence of molten lava in a tube or tumulus resulted in surface temperatures that were at least 10-degrees-C above ambient. The temperature map also clearly defined the boundaries of hydrothermal plumes which resulted from the entry of lava into the ocean. The emissivity map revealed the boundaries between individual flow units within the Kupaianaha field. In general, the emissivity of the flows varied systematically with age but the relationship between age and emissivity was not unique. Distinct spectral anomalies, indicative of silica-rich surface materials, were mapped near fumaroles and ocean entry sites. This apparent enrichment in silica may have resulted from an acid-induced leaching of cations from the surfaces of glassy flows. Such incipient alteration may have been the cause for virtually all of the emissivity variations observed on the flow field, the spectral anomalies representing areas where the acid attack was most intense. RP REALMUTO, VJ (reprint author), JET PROP LAB,MS 183-501,PASADENA,CA 91109, USA. NR 0 TC 44 Z9 44 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0258-8900 J9 B VOLCANOL JI Bull. Volcanol. PD DEC PY 1992 VL 55 IS 1-2 BP 33 EP 44 DI 10.1007/BF00301118 PG 12 WC Geosciences, Multidisciplinary SC Geology GA KC332 UT WOS:A1992KC33200004 ER PT J AU JOHNSON, SW THEDINGA, JF KOSKI, KV AF JOHNSON, SW THEDINGA, JF KOSKI, KV TI LIFE-HISTORY OF JUVENILE OCEAN-TYPE CHINOOK SALMON (ONCORHYNCHUS-TSHAWYTSCHA) IN THE SITUK RIVER, ALASKA SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID BRITISH-COLUMBIA; HABITAT UTILIZATION; STREAM; SELECTION; ESTUARY; KISUTCH; OREGON; FALL AB Distribution, abundance, habitat preference, migration and residence timing, seawater tolerance, and size were determined for juvenile ocean-type (age 0) chinook salmon (Oncorhynchus tshawytscha) in the Situk River, Alaska. Chinook primarily occupied main-stem habitats (channel edges in spring, pools and willow edges in summer). Peak chinook densities in the upper and lower main stem were 96 and 76 fish/100 m2, respectively. Chinook migrated downstream in two phases: a spring dispersal of emergent fry and a summer migration. Chinook marked in the upper river in late June and early July were recaptured 20 km downstream in the lower river in late July. Marked chinook resided in the lower river up to 34 d. Mean fork length of chinook in the lower river increased from 40 mm in May to 80 mm in early August. By late August, chinook had emigrated from the lower river at a size of approximately 80 mm. Fish this size were seawater tolerant and had the physical appearance of smolts. Ocean-type chinook in the Situk River are unique because in most Alaskan streams, chinook are stream-type (rear in freshwater at least 1 yr). RP JOHNSON, SW (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,AUKE BAY LAB,11305 GLACIER HIGHWAY,JUNEAU,AK 99801, USA. NR 36 TC 18 Z9 18 U1 0 U2 10 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD DEC PY 1992 VL 49 IS 12 BP 2621 EP 2629 DI 10.1139/f92-290 PG 9 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA KL532 UT WOS:A1992KL53200022 ER PT J AU Davies, ME Abalakin, VK Brahic, A Bursa, M Chovitz, BH Lieske, JH Seidelmann, RK Sinclair, AT Tjuflin, YS AF Davies, M. E. Abalakin, V. K. Brahic, A. Bursa, M. Chovitz, B. H. Lieske, J. H. Seidelmann, R. K. Sinclair, A. T. Tjuflin, Y. S. TI REPORT OF THE IAU/IAG/COSPAR WORKING GROUP ON CARTOGRAPHIC COORDINATES AND ROTATIONAL ELEMENTS OF THE PLANETS AND SATELLITES: 1991 SO CELESTIAL MECHANICS & DYNAMICAL ASTRONOMY LA English DT Article DE Cartographic coordinates; rotation axes; rotation periods; sizes and shapes AB Every three years the IAU/IAG/COSPAR Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites revises tables giving the directions of the north poles of rotation and the prime meridians of the planets and satellites. Also presented are revised tables giving their sizes and shapes. C1 [Davies, M. E.] RAND Corp, Santa Monica, CA USA. [Abalakin, V. K.] Inst Theoret Astron, St Petersburg, Russia. [Brahic, A.] Observ Paris, Meudon, France. [Bursa, M.] Astron Inst, Prague, Czech Republic. [Chovitz, B. H.] STX, Lanham, MD USA. [Lieske, J. H.] CALTECH, Jet Prop Lab, Pasadena, CA USA. [Seidelmann, R. K.] USN Observ, Washington, DC 20392 USA. [Sinclair, A. T.] Royal Greenwich Observ, Cambridge CB3 0EZ, England. [Tjuflin, Y. S.] Cent Res Inst Geodesy Air Survey & Mapping TsNIIG, Moscow, Russia. RP Davies, ME (reprint author), RAND Corp, Santa Monica, CA USA. NR 14 TC 71 Z9 71 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0923-2958 J9 CELEST MECH DYN ASTR JI Celest. Mech. Dyn. Astron. PD DEC PY 1992 VL 53 IS 4 BP 377 EP 397 PG 21 WC Astronomy & Astrophysics; Mathematics, Interdisciplinary Applications SC Astronomy & Astrophysics; Mathematics GA V05NA UT WOS:000207131500006 ER PT J AU BLANKENHORN, DH SELZER, RH MACK, WJ CRAWFORD, DW POGODA, J LEE, PL SHIRCORE, AM AZEN, SP AF BLANKENHORN, DH SELZER, RH MACK, WJ CRAWFORD, DW POGODA, J LEE, PL SHIRCORE, AM AZEN, SP TI EVALUATION OF COLESTIPOL NIACIN THERAPY WITH COMPUTER-DERIVED CORONARY END-POINT MEASURES - A COMPARISON OF DIFFERENT MEASURES OF TREATMENT EFFECT SO CIRCULATION LA English DT Article DE ATHEROSCLEROSIS; CLINICAL TRIALS; QUANTITATIVE CORONARY ANGIOGRAPHY; REGRESSION ID SAPHENOUS-VEIN GRAFTS; ARTERY DISEASE; UNSTABLE ANGINA; HEART-DISEASE; BYPASS GRAFTS; ATHEROSCLEROSIS; PROGRESSION; REGRESSION; CHOLESTYRAMINE; INTERVENTION AB Background. The Cholesterol Lowering Atherosclerosis Study has demonstrated beneficial effect of colestipol/niacin on coronary atherosclerosis using a panel-determined global coronary change score. We now report treatment group comparisons using quantitative coronary angiographic (QCA) measures from all processable segments in 85 of 162 randomly selected baseline/2-year film pairs. Methods and Results. Treatment benefit was established for percent stenosis for either continuous or categorical analyses with regression established regardless of the per-patient scoring procedure. In addition, treatment benefit favoring regression was established in some cases for roughness and for percent involvement, a longitudinal estimate of the percent of coronary surface involved by raised lesions. Benefit on minimum diameter was directly related to whether the segment was proximal to a graft insertion and hemodynamically related to the bypass graft. QCA correlates of panel-determined progression were increases in percent stenosis and numbers of occluded lesions in native arteries and the number of progressing lesions in bypass grafts. Conclusions. These results demonstrate that a variety of computer measures can be used as end points in coronary angiographic therapy trials, but change in percent stenosis correlates best with visual panel assessments and best reflects the treatment benefit; when treatment effect sizes are moderate to large, the required sample size of coronary angiographic trials can be reduced when QCA is used. C1 UNIV SO CALIF,SCH MED,ATHEROSCLEROSIS RES INST,DEPT PREVENT MED,2025 ZONAL AVE,RMR 102,LOS ANGELES,CA 90033. UNIV SO CALIF,SCH MED,DEPT MED,LOS ANGELES,CA 90033. JET PROP LAB,PASADENA,CA 91109. FU NHLBI NIH HHS [R01-HL-45005] NR 38 TC 34 Z9 34 U1 0 U2 0 PU AMER HEART ASSOC PI DALLAS PA 7272 GREENVILLE AVENUE, DALLAS, TX 75231-4596 SN 0009-7322 J9 CIRCULATION JI Circulation PD DEC PY 1992 VL 86 IS 6 BP 1701 EP 1709 PG 9 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA KB491 UT WOS:A1992KB49100003 PM 1451241 ER PT J AU WATSON, CL MORROW, HA BRILL, RW AF WATSON, CL MORROW, HA BRILL, RW TI PROTEOLYSIS OF SKELETAL-MUSCLE IN YELLOWFIN TUNA (THUNNUS-ALBACARES) - EVIDENCE OF CALPAIN ACTIVATION SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY LA English DT Article ID BURNT TUNA; TEMPERATURE; METABOLISM; MYOFIBRILS; HISTIDINE; PH AB 1. White muscle of yellowfin tuna is subject to a form of deterioration known as "burnt tuna". 2. TEM and SDS-PAGE were used to quantify cellular differences in deteriorated white muscle of yellowfin tuna. 3. Electron micrographs showed a significant loss of Z-disc integrity and an increase in intracellular edema in burnt tuna. 4. Electrophoresis established that a specific doublet of proteins, 42 kD and 46 kD was lost. 5. Proteolysis of isolated myofibrils incubated in calpain (EC 3.4.22.17) was greatest at pH 7.5 and was selective for intermediate molecular weight proteins. 6. This evidence suggests that burnt tuna is a specific and limited proteolysis of myofibrillar structural proteins characteristic of calpain proteolysis. C1 UNIV HAWAII,DEPT PHYSIOL,HONOLULU,HI 96822. UNIV HAWAII,DEPT ANAT,HONOLULU,HI 96822. NATL MARINE FISHERIES SERV,HONOLULU,HI. RP WATSON, CL (reprint author), BROWN UNIV,PHYSIOL SECT,BOX G-B328,PROVIDENCE,RI 02912, USA. NR 27 TC 15 Z9 15 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0305-0491 J9 COMP BIOCHEM PHYS B JI Comp. Biochem. Physiol. B-Biochem. Mol. Biol. PD DEC PY 1992 VL 103 IS 4 BP 881 EP 887 DI 10.1016/0305-0491(92)90209-A PG 7 WC Biochemistry & Molecular Biology; Zoology SC Biochemistry & Molecular Biology; Zoology GA KC936 UT WOS:A1992KC93600017 ER PT J AU LIU, CH WONG, TC KANDIL, OA AF LIU, CH WONG, TC KANDIL, OA TI PREDICTION OF ASYMMETRIC VORTICAL FLOWS AROUND SLENDER BODIES USING NAVIER-STOKES EQUATIONS SO FLUID DYNAMICS RESEARCH LA English DT Article; Proceedings Paper CT INTERNATIONAL WORKSHOP ON SUPERCOMPUTING AND EXPERIMENTS IN FLUID DYNAMICS CY SEP 03-05, 1991 CL NOBEYAMA, JAPAN AB Steady and unsteady asymmetric vortical flows around slender bodies at high angles of attack are solved using the unsteady, compressible, this-layer Navier-Stokes equations. An implicit, upwind-biased. flux-difference splitting, finite-volume scheme is used for the numerical computations. For supersonic flows past point cones, the locally conical flow assumption has been used for efficient computational studies of this phenomenon. Asymmetric flows past a 5-degrees semiapex-angle circular cone at different angles of attack, free-stream Mach numbers, and Reynolds numbers has been studied in responses to different sources of disturbances. The effects of grid fineness and computational domain size have also been investigated. Next, the responses of three-dimensional supersonic asymmetric flow around a 5-degrees circular cone at different angles of attack and Reynolds numbers to short-duration sideslip disturbances are presented. The results show that flow asymmetry becomes stronger as the Reynolds number and angles of attack are increased. The asymmetric solutions show spatial vortex shedding which is qualitatively similar to the temporal vortex shedding of the unsteady locally conical flow. A cylindrical afterbody is also added to the same cone to study the effect of a cylindrical part on the flow asymmetry. One of the cases of flow over a cone-cylinder configuration is validated fairly well by experimental data. RP LIU, CH (reprint author), NASA,LANGLEY RES CTR,COMPUTAT AERODYNAM BRANCH,HAMPTON,VA 23681, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-5983 J9 FLUID DYN RES JI Fluid Dyn. Res. PD DEC PY 1992 VL 10 IS 4-6 BP 409 EP 450 DI 10.1016/0169-5983(92)90032-R PG 42 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KE062 UT WOS:A1992KE06200011 ER PT J AU DURISEN, RH BODE, PW CUZZI, JN CEDERBLOOM, SE MURPHY, BW AF DURISEN, RH BODE, PW CUZZI, JN CEDERBLOOM, SE MURPHY, BW TI BALLISTIC TRANSPORT IN PLANETARY RING-SYSTEMS DUE TO PARTICLE EROSION MECHANISMS SO ICARUS LA English DT Article ID SATURNS RINGS; ENCKE GAP; RESONANCE STRUCTURES; RADIO OCCULTATION; SHARP EDGES; DYNAMICS; SIMULATIONS; SATELLITE; EXAMPLES; MOONLET C1 MAX PLANCK INST EXTRATERRESTR PHYS,W-8046 GARCHING,GERMANY. NASA,AMES RES CTR,DIV SPACE SCI,MOFFETT FIELD,CA 94035. CORNELL UNIV,DEPT ASTRON,ITHACA,NY 14853. RP DURISEN, RH (reprint author), INDIANA UNIV,DEPT ASTRON,BLOOMINGTON,IN 47405, USA. NR 46 TC 44 Z9 44 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 364 EP 393 DI 10.1016/0019-1035(92)90106-H PG 30 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400008 ER PT J AU SHOWALTER, MR POLLACK, JB OCKERT, ME DOYLE, LR DALTON, JB AF SHOWALTER, MR POLLACK, JB OCKERT, ME DOYLE, LR DALTON, JB TI A PHOTOMETRIC-STUDY OF SATURNS F-RING SO ICARUS LA English DT Article ID PARTICLE-SIZE DISTRIBUTIONS; VOYAGER-1 RADIO OCCULTATION; LIGHT-SCATTERING; JUPITERS RING; MICROWAVE; ARC; WAVELENGTHS; CONSTRAINTS; FEATURES; NEPTUNE C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RP SHOWALTER, MR (reprint author), STANFORD UNIV,CTR RADAR ASTRON,223 DURAND BLDG,STANFORD,CA 94305, USA. NR 59 TC 94 Z9 94 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 394 EP 411 DI 10.1016/0019-1035(92)90107-I PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400009 ER PT J AU NICHOLSON, PD HAMILTON, DP MATTHEWS, K YODER, CF AF NICHOLSON, PD HAMILTON, DP MATTHEWS, K YODER, CF TI NEW OBSERVATIONS OF SATURNS COORBITAL SATELLITES SO ICARUS LA English DT Article ID CO-ORBITING SATELLITES; INTERNAL STRUCTURE; INNER SATELLITES; RINGS; URANUS; EPIMETHEUS; PIONEER-11; RESONANCE; MICRONS; MIMAS C1 CALTECH, PALOMAR OBSERV, PASADENA, CA 91125 USA. JET PROP LAB, PASADENA, CA 91109 USA. RP CORNELL UNIV, DEPT ASTRON, ITHACA, NY 14853 USA. NR 39 TC 54 Z9 55 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 464 EP 484 DI 10.1016/0019-1035(92)90111-J PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400013 ER PT J AU WESTPHAL, JA BAUM, WA INGERSOLL, AP BARNET, CD DEJONG, EM DANIELSON, GE CALDWELL, J AF WESTPHAL, JA BAUM, WA INGERSOLL, AP BARNET, CD DEJONG, EM DANIELSON, GE CALDWELL, J TI HUBBLE SPACE TELESCOPE OBSERVATIONS OF THE 1990 EQUATORIAL DISTURBANCE ON SATURN - IMAGES, ALBEDOS, AND LIMB DARKENING SO ICARUS LA English DT Article ID PLANETARY CAMERA IMAGES; ATMOSPHERE; PERFORMANCE C1 UNIV WASHINGTON,DEPT ASTRON,SEATTLE,WA 98105. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. JET PROP LAB,DIV EARTH & SPACE SCI,PASADENA,CA 91109. INST SPACE & TERR SCI,SPACE ASTROPHYS LAB,CONCORD L4K 3C8,ON,CANADA. RP WESTPHAL, JA (reprint author), CALTECH,DIV GEOL & PLANETARY SCI,PASADENA,CA 91125, USA. RI Barnet, Christopher/F-5573-2010 NR 30 TC 32 Z9 32 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 485 EP 498 DI 10.1016/0019-1035(92)90112-K PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400014 ER PT J AU BARNET, CD WESTPHAL, JA BEEBE, RF HUBER, LF AF BARNET, CD WESTPHAL, JA BEEBE, RF HUBER, LF TI HUBBLE SPACE TELESCOPE OBSERVATIONS OF THE 1990 EQUATORIAL DISTURBANCE ON SATURN - ZONAL WINDS AND CENTRAL MERIDIAN ALBEDOS SO ICARUS LA English DT Article ID PLANETARY CAMERA IMAGES; SPECTRA; FIELD; ATMOSPHERE C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. CALTECH,PASADENA,CA 91125. NEW MEXICO STATE UNIV,DEPT ASTRON,LAS CRUCES,NM 88003. RI Barnet, Christopher/F-5573-2010 NR 24 TC 50 Z9 50 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 499 EP 511 DI 10.1016/0019-1035(92)90113-L PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400015 ER PT J AU ALLEN, M YUNG, YL GLADSTONE, GR AF ALLEN, M YUNG, YL GLADSTONE, GR TI THE RELATIVE ABUNDANCE OF ETHANE TO ACETYLENE IN THE JOVIAN STRATOSPHERE SO ICARUS LA English DT Article ID RATE CONSTANTS; CROSS-SECTIONS; PHOTOCHEMISTRY; ATMOSPHERE; KINETICS; TEMPERATURE; RADICALS; JUPITER; HYDROCARBONS; C2H2 C1 CALTECH,DIV GEOL & PLANETARY SCI,PASADENA,CA 91125. UNIV CALIF BERKELEY,SPACE SCI LAB,EARTH & PLANETARY ATMOSPHERES GRP,BERKELEY,CA 94720. RP ALLEN, M (reprint author), JET PROP LAB,DIV EARTH & SPACE SCI,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 45 TC 54 Z9 54 U1 0 U2 4 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 527 EP 533 DI 10.1016/0019-1035(92)90115-N PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400017 PM 11538055 ER PT J AU ORTON, GS LACY, JH ACHTERMANN, JM PARMAR, P BLASS, WE AF ORTON, GS LACY, JH ACHTERMANN, JM PARMAR, P BLASS, WE TI THERMAL SPECTROSCOPY OF NEPTUNE - THE STRATOSPHERIC TEMPERATURE, HYDROCARBON ABUNDANCES, AND ISOTOPIC-RATIOS SO ICARUS LA English DT Article ID ROTOTRANSLATIONAL ABSORPTION-SPECTRA; OUTER SOLAR-SYSTEM; GIANT PLANETS; INFRARED OBSERVATIONS; VOYAGER MEASUREMENTS; MOIST CONVECTION; MU-M; URANUS; ATMOSPHERE; ETHANE C1 UNIV TEXAS,DEPT ASTRON,AUSTIN,TX 78712. UNIV TENNESSEE,CTR COMP,KNOXVILLE,TN 37996. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. RP ORTON, GS (reprint author), JET PROP LAB,MS 169-237,4800 OAK GROVE DR,PASADENA,CA 91109, USA. RI Blass, William/A-2792-2008 NR 65 TC 52 Z9 52 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 541 EP 555 DI 10.1016/0019-1035(92)90117-P PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400019 ER PT J AU KEPPENNE, CL AF KEPPENNE, CL TI OROGRAPHICALLY FORCED-OSCILLATIONS IN A DYNAMIC-MODEL OF THE MARTIAN ATMOSPHERE SO ICARUS LA English DT Article ID GENERAL-CIRCULATION; TOPOGRAPHY; EQUATION C1 UNIV CALIF LOS ANGELES,CTR CLIMATE DYNAM,DEPT ATMOSPHER SCI,LOS ANGELES,CA 90024. RP KEPPENNE, CL (reprint author), JET PROP LAB,SPACE GEODET SCI & APPLICAT GRP,PASADENA,CA 91109, USA. NR 27 TC 3 Z9 3 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD DEC PY 1992 VL 100 IS 2 BP 598 EP 607 DI 10.1016/0019-1035(92)90120-V PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KF814 UT WOS:A1992KF81400022 ER PT J AU THORBURN, MA BISWAS, A TRIPATHI, VK AF THORBURN, MA BISWAS, A TRIPATHI, VK TI APPLICATION OF THE METHOD OF LINES TO PLANAR TRANSMISSION-LINES IN WAVE-GUIDES WITH COMPOSITE CROSS-SECTIONAL GEOMETRIES SO IEE PROCEEDINGS-H MICROWAVES ANTENNAS AND PROPAGATION LA English DT Article DE TRANSMISSION LINES; WAVE-GUIDES; METHOD OF LINES ID PROPAGATION STRUCTURES AB The analysis of a class of planar transmission lines in composite uniform waveguides which have a circular boundary over part of the cross-section and a rectangular boundary over the remainder is introduced. It is shown that the method of lines can be applied to such composite structures by taking advantage of the canonical geometry in each region. Results for the dispersion characteristics and impedance of a finline in such a structure are calculated. C1 INDIA TEL IND,BANGALORE,INDIA. OREGON STATE UNIV,DEPT ELECT & COMP ENGN,CORVALLIS,OR 97331. RP THORBURN, MA (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD, ENGLAND SG1 2AY SN 0950-107X J9 IEE PROC-H PD DEC PY 1992 VL 139 IS 6 BP 542 EP 544 PG 3 WC Optics SC Optics GA KD337 UT WOS:A1992KD33700011 ER PT J AU CUNNINGHAM, TJ FOSSUM, ER BAIER, SM AF CUNNINGHAM, TJ FOSSUM, ER BAIER, SM TI AN ANALYSIS OF THE TEMPERATURE-DEPENDENCE OF THE GATE CURRENT IN COMPLEMENTARY HETEROJUNCTION FIELD-EFFECT TRANSISTORS SO IEEE ELECTRON DEVICE LETTERS LA English DT Article ID CHANNEL AB The temperature dependence of the gate current versus the gate voltage in complementary heterojunction field-effect transistors (CHFET's) is examined. An analysis indicates that the gate conduction is due to a combination of thermionic emission, thermionic-field emission, and conduction through a temperature-activated resistance. The thermionic-field emission is consistent with tunneling through the AlGaAs insulator. The activation energy of the resistance is consistent with the ionization energy associated with the DX center in the AlGaAs. Methods reducing the gate current are discussed. C1 HONEYWELL INC,SYST & RES CTR,BLOOMINGTON,MN 55420. RP CUNNINGHAM, TJ (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0741-3106 J9 IEEE ELECTR DEVICE L JI IEEE Electron Device Lett. PD DEC PY 1992 VL 13 IS 12 BP 645 EP 647 DI 10.1109/55.192872 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA JZ437 UT WOS:A1992JZ43700017 ER PT J AU CWIK, T AF CWIK, T TI COUPLING FINITE-ELEMENT AND INTEGRAL-EQUATION SOLUTIONS USING DECOUPLED BOUNDARY MESHES SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article ID ELECTROMAGNETIC SCATTERING PROBLEMS; BODIES; REVOLUTION; CYLINDERS AB A method is outlined for calculating scattered fields from inhomogeneous penetrable objects using a coupled finite element-integral equation solution. The finite element equation can efficiently model fields in penetrable and inhomogeneous regions, while the integral equation exactly models fields on the finite element mesh boundary and in the exterior region. By decoupling the interior finite element and exterior integral equation meshes, considerable flexibility is found in both the number of field expansion points as well as their density. Only the nonmetal portions of the object need be modeled using a finite element expansion; exterior perfect conducting surfaces are modeled using an integral equation with a single unknown field since E(tan) is identically zero on these surfaces. Numerical convergence, accuracy, and stability at interior resonant frequencies am studied in detail. RP CWIK, T (reprint author), JET PROP LAB, PASADENA, CA 91109 USA. NR 18 TC 21 Z9 21 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD DEC PY 1992 VL 40 IS 12 BP 1496 EP 1504 DI 10.1109/8.204740 PG 9 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA KU313 UT WOS:A1992KU31300006 ER PT J AU Venbrux, J Yeh, PS Liu, MN AF Venbrux, Jack Yeh, Pen-Shu Liu, Muye N. TI A VLSI Chip Set for High-Speed Lossless Data Compression SO IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY LA English DT Article AB This paper reports a VLSI implementation of a lossless data compression algorithm. This is the first implementation of an encoder/decoder chip set that employs the Rice algorithm and provides an introduction to the algorithm as well as a description of the high performance hardware. The algorithm is adaptive over a wide entropy range. its performance on several 8-b test images has been shown to exceed other techniques employing differential pulse code modulation (DPCM) followed by arithmetic coding, adaptive Huffman coding, and a Lempel-Ziv-Welch (LZW) algorithm. A major feature of the algorithm is that it requires no look-up tables or external RAM. There are only 71,000 transistors required to implement the encoder and decoder. Each chip was fabricated in a 1.0-mu m CMOS process and both are only 5 mm in a side. A comparison is made with other hardware realizations. Under laboratory conditions, the encoder compresses at a rate in excess of 50 Msamples / s and the decoder operates at 25 Msamples / s. The current implementation processes quantized data from 4 to 14 b / sample. The chip set could be used in video systems as a component in a lossy compression scheme to provide real-time, efficient, variable-length coding and decoding of DCT transform coefficients and the low-frequency band found in subband coders. C1 [Venbrux, Jack] Univ New Mexico, VLSI Syst Design, NASA SERC, Albuquerque, NM 87106 USA. [Liu, Muye N.] IBM Corp, Adv Workstn Div, Austin, TX 78758 USA. [Yeh, Pen-Shu] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Venbrux, J (reprint author), Univ New Mexico, VLSI Syst Design, NASA SERC, Albuquerque, NM 87106 USA. NR 11 TC 15 Z9 15 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1051-8215 J9 IEEE T CIRC SYST VID JI IEEE Trans. Circuits Syst. Video Technol. PD DEC PY 1992 VL 2 IS 4 BP 381 EP 391 DI 10.1109/76.168903 PG 11 WC Engineering, Electrical & Electronic SC Engineering GA V04SI UT WOS:000207077700005 ER PT J AU MCNULTY, PJ BEAUVAIS, WJ REED, RA ROTH, DR STASSINOPOULOS, EG BRUCKER, GJ AF MCNULTY, PJ BEAUVAIS, WJ REED, RA ROTH, DR STASSINOPOULOS, EG BRUCKER, GJ TI CHARGE COLLECTION AT LARGE ANGLES OF INCIDENCE SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 29TH IEEE ANNUAL INTERNATIONAL NUCLEAR AND SPACE RADIATION EFFECTS CONF AND SHORT COURSE CY JUL 13-17, 1992 CL NEW ORLEANS, LA SP IEEE, RADIAT EFFECTS COMM ID SINGLE AB Charge collection exhibited by p-n junctions, which have at least one small dimension, deviates from the geometric assumptions commonly used in SEU testing. The amount of charge collected did not increase with the secant of the angle of incidence. The number of events under the peak in the charge collection spectrum did not decrease as the cosine of the angle of incidence. Both the position of the peak and the number of events under the peak measured at a given angle of incidence depended upon which symmetry axis of the device was chosen to be the axis of rotation. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP MCNULTY, PJ (reprint author), CLEMSON UNIV,DEPT PHYS & ASTRON,CLEMSON,SC 29634, USA. NR 8 TC 17 Z9 17 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1992 VL 39 IS 6 BP 1622 EP 1629 DI 10.1109/23.211344 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA KM885 UT WOS:A1992KM88500007 ER PT J AU NICHOLS, DK COSS, JR WATSON, RK SCHWARTZ, HR PEASE, RL AF NICHOLS, DK COSS, JR WATSON, RK SCHWARTZ, HR PEASE, RL TI AN OBSERVATION OF PROTON-INDUCED LATCHUP SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 29TH IEEE ANNUAL INTERNATIONAL NUCLEAR AND SPACE RADIATION EFFECTS CONF AND SHORT COURSE CY JUL 13-17, 1992 CL NEW ORLEANS, LA SP IEEE, RADIAT EFFECTS COMM AB A device having a low LET latchup threshold with heavy ions was irradiated with 50-, 90- and 148-MeV protons at three different bias levels. The part exhibited latchup under all test conditions. C1 MISSION RES CORP,ALBUQUERQUE,NM 87106. RP NICHOLS, DK (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 3 TC 20 Z9 20 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1992 VL 39 IS 6 BP 1654 EP 1656 DI 10.1109/23.211349 PN 1 PG 3 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA KM885 UT WOS:A1992KM88500012 ER PT J AU LIU, MN WHITAKER, S AF LIU, MN WHITAKER, S TI LOW-POWER SEU IMMUNE CMOS MEMORY-CIRCUITS SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 29TH IEEE ANNUAL INTERNATIONAL NUCLEAR AND SPACE RADIATION EFFECTS CONF AND SHORT COURSE CY JUL 13-17, 1992 CL NEW ORLEANS, LA SP IEEE, RADIAT EFFECTS COMM ID INDUCED SOFT ERRORS; SRAM; UPSETS; DESIGN AB This paper1 reports a design improvement for CMOS static memory circuits hardened against Single Event Upset (SEU) using a recently proposed logic/circuit design technique. This improvement drastically reduces static power consumption, reduces the number of transistors required in a D flip flop design and eliminates the possibility of capturing an upset state in the slave section during a clock transition. RP LIU, MN (reprint author), UNIV IDAHO,NASA,SPACE ENGN RES CTR VLSI SYST DESIGN,MOSCOW,ID 83843, USA. NR 23 TC 53 Z9 58 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1992 VL 39 IS 6 BP 1679 EP 1684 DI 10.1109/23.211353 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA KM885 UT WOS:A1992KM88500016 ER PT J AU STASSINOPOULOS, EG BRUCKER, GJ CALVEL, P BAIGET, A PEYROTTE, C GAILLARD, R AF STASSINOPOULOS, EG BRUCKER, GJ CALVEL, P BAIGET, A PEYROTTE, C GAILLARD, R TI CHARGE GENERATION BY HEAVY-IONS IN POWER MOSFETS, BURNOUT SPACE PREDICTIONS, AND DYNAMIC SEB SENSITIVITY SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 29TH IEEE ANNUAL INTERNATIONAL NUCLEAR AND SPACE RADIATION EFFECTS CONF AND SHORT COURSE CY JUL 13-17, 1992 CL NEW ORLEANS, LA SP IEEE, RADIAT EFFECTS COMM AB This study describes the transport, energy loss, and charge production of heavy ions in the sensitive regions of IRF 150 power MOSFETs. The dependence and variation of transport parameters with ion type and energy, relative to the requirements for Single Event Burnout (SEB) in this part type are discussed. Test data taken with this power MOSFET are used together with analyses by means of a computer code of the ion energy loss and charge production in the device to establish criteria for burnout and parameters for space predictions. These parameters are then used in an application to predict burnout rates in a geostationary orbit for power converters operating in a dynamic mode. Comparisons of rates for different geometries in simulating SEU sensitive volumes are presented. C1 ALCATEL SPACE,TOULOUSE,FRANCE. NUCLETUDES SA,LES ULIS,FRANCE. RP STASSINOPOULOS, EG (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 19 TC 16 Z9 18 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1992 VL 39 IS 6 BP 1704 EP 1711 DI 10.1109/23.211357 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA KM885 UT WOS:A1992KM88500020 ER PT J AU BOGORAD, A LICHTIN, DA BOWMAN, C ARMENTI, J PENCIL, E SARMIENTO, C AF BOGORAD, A LICHTIN, DA BOWMAN, C ARMENTI, J PENCIL, E SARMIENTO, C TI THE EFFECTS OF 1 KW CLASS ARCJET THRUSTER PLUMES ON SPACECRAFT CHARGING AND SPACECRAFT THERMAL CONTROL MATERIALS SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 29TH IEEE ANNUAL INTERNATIONAL NUCLEAR AND SPACE RADIATION EFFECTS CONF AND SHORT COURSE CY JUL 13-17, 1992 CL NEW ORLEANS, LA SP IEEE, RADIAT EFFECTS COMM AB Arcjet thrusters are soon to be employed for north/south stationkeeping on commercial communications satellites. A series of tests have been performed to evaluate the possible effects of these thrusters on spacecraft charging and the degradation of thermal control material. During our tests the interaction between arcjet plumes and both charged and uncharged surfaces did not cause any significant material degradation. In addition, firing an arcjet thruster benignly reduced the potential of charged surfaces to near zero. C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. RP BOGORAD, A (reprint author), GE,DIV ASTROSPACE,PRINCETON,NJ 08543, USA. NR 12 TC 3 Z9 3 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1992 VL 39 IS 6 BP 1783 EP 1789 DI 10.1109/23.211367 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA KM885 UT WOS:A1992KM88500030 ER PT J AU SOLI, GA BLAES, BR BUEHLER, MG RAY, K LIN, YS AF SOLI, GA BLAES, BR BUEHLER, MG RAY, K LIN, YS TI CRRES MICROELECTRONIC TEST CHIP ORBITAL DATA-II SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 29TH IEEE ANNUAL INTERNATIONAL NUCLEAR AND SPACE RADIATION EFFECTS CONF AND SHORT COURSE CY JUL 13-17, 1992 CL NEW ORLEANS, LA SP IEEE, RADIAT EFFECTS COMM AB Data from a MOSFET matrix on two JPL CRRES chips, each behind different amounts of shielding, is presented. Space damage factors are nearly identical to ground test values for pMOSFETs. The results from neighboring rows of MOSFETs show similar radiation degradation. The SRD (Space Radiation Dosimeter) is used to measure the total dose accumulated by the JPL chips. A parameter extraction algorithm that does not under estimate threshold voltage shifts is used. Temperature effects are removed from the MOSFET data. C1 PHILLIPS LAB,AFSC,BEDFORD,MA 01731. SILICON SYST INC,TUSTIN,CA 92680. RP SOLI, GA (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 7 TC 10 Z9 10 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1992 VL 39 IS 6 BP 1840 EP 1845 DI 10.1109/23.211375 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA KM885 UT WOS:A1992KM88500038 ER PT J AU SHAW, DC LOWRY, L MACWILLIAMS, KP BARNES, CE AF SHAW, DC LOWRY, L MACWILLIAMS, KP BARNES, CE TI OBSERVATION OF RADIATION-INDUCED CHANGES IN STRESS AND ELECTRICAL-PROPERTIES IN MOS DEVICES SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 29TH IEEE ANNUAL INTERNATIONAL NUCLEAR AND SPACE RADIATION EFFECTS CONF AND SHORT COURSE CY JUL 13-17, 1992 CL NEW ORLEANS, LA SP IEEE, RADIAT EFFECTS COMM ID MECHANICAL-STRESS; INTERFACE; DEPENDENCE; DAMAGE; SIO2 AB Strain measurements using x-ray diffraction were performed on irradiated commercial and radiation hardened metal gate CMOS devices in addition to polysilicon gate NMOS devices. I-V curves were taken and V(ot) and V(it) were separated using the subthreshold slope method for all devices. A correlation has been shown to exist between physical strain relaxation and the electrical properties as a function of radiation dose and recovery. Data shown suggest that the physical response (strain relaxation) in the silicon at the oxide interface is a measure of the type of damage induced and the recovery mechanism. Post radiation measurements of DELTAV(it) and DELTAV(ot) taken immediately after irradiation support the conclusions of Zekeriya and Ma and Kasama, et al.; compressive stress at the silicon/SiO2 interface does reduce radiation damage in the device. C1 AEROSP CORP,LOS ANGELES,CA 90009. RP SHAW, DC (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 19 TC 7 Z9 7 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1992 VL 39 IS 6 BP 2146 EP 2151 DI 10.1109/23.211415 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA KM885 UT WOS:A1992KM88500078 ER PT J AU ECKERT, MP BUCHSBAUM, G WATSON, AB AF ECKERT, MP BUCHSBAUM, G WATSON, AB TI SEPARABILITY OF SPATIOTEMPORAL SPECTRA OF IMAGE SEQUENCES SO IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE LA English DT Letter AB We calculated the spatiotemporal power spectrum of 14 image sequences in order to determine the degree to which the spectra are separable in space and time and to assess the validity of the commonly used exponential correlation model found in the literature. We expand the spectrum by a singular value decomposition into a sum of separable terms and define an index of spatiotemporal separability as the fraction of the signal energy that can be represented by the first (largest) separable term. All spectra were found to be highly separable with an index of separability above 0.98. The power spectra of the sequences were well fit by a separable model of the form P(k, f) = ab/(4pi3)/((a/2pi)2 + k2)3/2((b/2pi)2 + f2) where k is radial spatial frequency, f is temporal frequency, and a,b are spatial and temporal model parameters that determine the effective spatiotemporal bandwidth of the signal. This power spectrum model corresponds to a product of exponential autocorrelation functions separable in space and time. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RP ECKERT, MP (reprint author), UNIV PENN,SCH ENGN & APPL SCI,DEPT BIOENGN,PHILADELPHIA,PA 19104, USA. NR 14 TC 13 Z9 13 U1 1 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 SN 0162-8828 J9 IEEE T PATTERN ANAL JI IEEE Trans. Pattern Anal. Mach. Intell. PD DEC PY 1992 VL 14 IS 12 BP 1210 EP 1213 DI 10.1109/34.177387 PG 4 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA KC573 UT WOS:A1992KC57300008 ER PT J AU GILLAN, DJ HOLDEN, K ADAM, S RUDISILL, M MAGEE, L AF GILLAN, DJ HOLDEN, K ADAM, S RUDISILL, M MAGEE, L TI HOW SHOULD FITTS LAW BE APPLIED TO HUMAN COMPUTER INTERACTION SO INTERACTING WITH COMPUTERS LA English DT Article DE HUMAN COMPUTER INTERACTION; FITTS LAW; TEXT EDITING; INTERFACE DESIGN ID MOTOR-PERFORMANCE; MOVEMENTS AB The paper challenges the notion that any Fitts' Law model can be applied generally to human-computer interaction, and proposes instead that applying Fitts' Law requires knowledge of the users' sequence of movements, direction of movement, and typical movement amplitudes as well as target sizes. Two experiments examined a text selection task with sequences of controlled movements (point-click and point-drag). For the point-click sequence, a Fitt's Law model that used the diagonal across the text object in the direction of pointing (rather than the horizontal extent of the text object) as the target size provided the best fit for the pointing time data, whereas for the point-drag sequence, a Fitts' Law model that used the vertical size of the text object as the target size gave the best fit. Dragging times were fitted well by Fitts' Law models that used either the vertical or horizontal size of the terminal character in the text object. Additional results of note were that pointing in the point-click sequence was consistently faster than in the point-drag sequence, and that pointing in either sequence was consistently faster than dragging. The discussion centres around the need to define task characteristics before applying Fitts' Law to an interface design or analysis, analyses of pointing and of dragging, and implications for interface design. C1 NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. RP GILLAN, DJ (reprint author), UNIV IDAHO,DEPT PSYCHOL,MOSCOW,ID 83843, USA. NR 21 TC 3 Z9 3 U1 1 U2 4 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0953-5438 J9 INTERACT COMPUT JI Interact. Comput. PD DEC PY 1992 VL 4 IS 3 BP 289 EP 313 DI 10.1016/0953-5438(92)90018-B PG 25 WC Computer Science, Cybernetics; Ergonomics SC Computer Science; Engineering GA JY129 UT WOS:A1992JY12900002 ER PT J AU AHN, KH IBRAHIM, MB AF AHN, KH IBRAHIM, MB TI LAMINAR TURBULENT OSCILLATING FLOW IN CIRCULAR PIPES SO INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW LA English DT Article DE UNSTEADY FLOWS; OSCILLATING FLOWS; TURBULENT MODELING; COMPUTATIONAL FLUID DYNAMICS; CRITICAL REYNOLDS NUMBER AB A two-dimensional oscillating flow analysis was conducted simulating the gas flow inside Stirling engine heat exchangers. Both laminar and turbulent oscillating pipe flow were investigated numerically for Re(max) = 1,920 (Va = 80), 10,800 (Va = 272), 19,300 (Va = 272), and 60,800 (Va = 126). The results are here compared with experimental results of previous investigators. Predictions of the flow regime on present oscillating flow conditions are also checked by comparing velocity amplitudes and phase difference with those from laminar theory and quasi-steady profile. A high Reynolds number k-epsilon turbulence model was used for turbulent oscillating pipe flow. Finally, the performance of the k-epsilon model was evaluated to explore the applicability of quasi-steady turbulent models to unsteady oscillating flow analysis. C1 CLEVELAND STATE UNIV,DEPT MECH ENGN,CLEVELAND,OH 44115. NASA,LEWIS RES CTR,INST COMPUTAT MECH PROP,CLEVELAND,OH 44135. NR 16 TC 15 Z9 16 U1 1 U2 12 PU BUTTERWORTH-HEINEMANN PI WOBURN PA 225 WILDWOOD AVE #UNITB PO BOX 4500, WOBURN, MA 01801-2084 SN 0142-727X J9 INT J HEAT FLUID FL JI Int. J. Heat Fluid Flow PD DEC PY 1992 VL 13 IS 4 BP 340 EP 346 DI 10.1016/0142-727X(92)90004-S PG 7 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA KF282 UT WOS:A1992KF28200004 ER PT J AU CHOUDHURY, BJ MAJOR, ER SMITH, EA BECKER, F AF CHOUDHURY, BJ MAJOR, ER SMITH, EA BECKER, F TI ATMOSPHERIC EFFECTS ON SMMR AND SSM/I 37 GHZ POLARIZATION DIFFERENCE OVER THE SAHEL SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID WATER-CONTENT; SIMULATION; EMISSION; CLOUDS AB The difference of vertically and horizontally polarized brightness temperatures (referred to here as the polarization difference, DELTAT) observed at 37 GHz frequency of the scanning multi-channel microwave radiometer (SMMR) on board the Nimbus-7 satellite and special sensor microwave imager (SSM/I) on board the DMSP-F8 satellite could provide useful information about land surface change within the span of these global observations, November 1978 to August 1987 for SMMR and July 1987 to present for SSM/I. The atmospheric effects on the DELTAT are studied over two 2.5-degrees by 2.5-degrees regions within the Sahel and Sudan zones of Africa from January 1985 to December 1986 through radiative transfer analysis using surface temperature, atmospheric water vapour and cloud optical thickness developed under the International Satellite Cloud Climatology Project (ISCCP). The atmospheric effects are also studied using surface observations of air temperature and vapour pressure at Niamey (13.5-degrees-N, 2.2-degrees-E) for the period January 1979 to December 1990. It is found that atmospheric effects alone cannot explain the observed temporal variation of DELTAT, although the atmosphere introduces important modulations on the observed seasonal variations of DELTAT due to rather significant seasonal variation of precipitable water vapour. Therefore, these DELTAT data should be corrected for atmospheric effects before any quantitative analysis of land surface change over the Sahel and Sudan zones. The entire global data set from December 1978 to December 1990 has been archived for unrestricted distribution and use. C1 SCI SYST & APPLICAT,SEABROOK,MD 20706. FLORIDA STATE UNIV,DEPT METEOROL,TALLAHASSEE,FL 32306. UNIV STRASBOURG 1,ECOLE NATL SUPER PHYS STRASBOURG,F-67070 STRASBOURG,FRANCE. RP CHOUDHURY, BJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HYDROL SCI BRANCH,GREENBELT,MD 20771, USA. NR 32 TC 19 Z9 20 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD DEC PY 1992 VL 13 IS 18 BP 3443 EP 3463 PG 21 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA KG700 UT WOS:A1992KG70000005 ER PT J AU NOOR, AK BURTON, WS AF NOOR, AK BURTON, WS TI 3-DIMENSIONAL SOLUTIONS FOR THE FREE-VIBRATIONS AND BUCKLING OF THERMALLY STRESSED MULTILAYERED ANGLE-PLY COMPOSITE PLATES SO JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME LA English DT Article ID BIDIRECTIONAL COMPOSITES; LAMINATED PLATES; BEHAVIOR AB Analytic three-dimensional elasticity solutions are presented for the free vibration and buckling of thermally stressed, multilayered, angle-ply composite plates. Sensitivity derivatives are also evaluated and used to study the sensitivity of the vibration and buckling responses to variations in the different lamination and material parameters of the plate. The plates are assumed to have rectangular geometry and an antisymmetric lamination with respect to the middle plane. The temperature is assumed to be independent of the surface coordinates, but has an arbitrary symmetric variation through the thickness of the plate. A linear, Duhamel-Neumann type constitutive model is used, and the material properties are assumed to be independent of temperature. The thermal plate response is subjected to time- varying perturbation displacements, strains, and stresses. A mixed formulation is used with the fundamental unknowns consisting of the six perturbation stress components and the three perturbation displacement components of the plate. The initial thermal deformations are accounted for. Each of the plate variables is decomposed into symmetric and antisymmetric components in the thickness direction, and is expressed in terms of a double Fourier series in the Cartesian surface coordinates. Numerical results are presented showing the effects of variations in material characteristics and fiber orientation of different layers, as well as the effects of initial thermal deformations on the vibrational and buckling responses of the plate, as well as their sensitivity derivatives. RP NOOR, AK (reprint author), UNIV VIRGINIA,NASA,LANGLEY RES CTR,CTR COMP STRUCT TECHNOL,HAMPTON,VA 23681, USA. NR 20 TC 34 Z9 34 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0021-8936 J9 J APPL MECH-T ASME JI J. Appl. Mech.-Trans. ASME PD DEC PY 1992 VL 59 IS 4 BP 868 EP 877 DI 10.1115/1.2894055 PG 10 WC Mechanics SC Mechanics GA KF532 UT WOS:A1992KF53200024 ER PT J AU GUPTA, SK DARNELL, WL WILBER, AC AF GUPTA, SK DARNELL, WL WILBER, AC TI A PARAMETERIZATION FOR LONGWAVE SURFACE RADIATION FROM SATELLITE DATA - RECENT IMPROVEMENTS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID STATISTICS AB Several improvements have been made recently to the parameterization for surface longwave radiation described by Gupta. Model constants have been modified in order to use meteorological data from the International Satellite Cloud Climatology Project instead of from the TIROS Operational Vertical Sounder data, primarily to take advantage of the vastly superior cloud information available from the former. Additional modifications were made to improve the estimation of cloud effect in the presence of low-level clouds. The latter modifications reduced the systematic error of the overcast-sky fluxes from 10.0 to 1.7 W m-2 and the random error from +/-18.9 to +/-6.3 W m-2 when compared to the fluxes computed with a detailed radiative transfer model. C1 NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,HAMPTON,VA 23665. RP GUPTA, SK (reprint author), LOCKHEED ENGN & SCI CO,LANGLEY PROGRAM OFF,144 RES DR,HAMPTON,VA 23666, USA. RI wilber, anne/F-6270-2011 NR 16 TC 87 Z9 91 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD DEC PY 1992 VL 31 IS 12 BP 1361 EP 1367 DI 10.1175/1520-0450(1992)031<1361:APFLSR>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KB863 UT WOS:A1992KB86300001 ER PT J AU WANG, JR BONCYK, WC DOD, LR SHARMA, AK AF WANG, JR BONCYK, WC DOD, LR SHARMA, AK TI RETRIEVAL OF TOTAL PRECIPITABLE WATER OVER HIGH-LATITUDE REGIONS USING RADIOMETRIC MEASUREMENTS NEAR 90 AND 183 GHZ SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID MICROWAVE RADIOMETRY; VAPOR PROFILES; MOISTURE PROFILES; OCEAN SURFACE; ALGORITHM; CLEAR AB Radiometric measurements at 90 GHz and three sideband frequencies near the peak water vapor absorption line of 183.3 GHz were made with Advanced Microwave Moisture Sounder (AMMS) aboard the NASA DC-8 aircraft during the Global Aerosol Backscatter Experiment (GLOBE) mission over the Pacific Ocean in November 1989. Some of the measurements over the high-latitude regions (>50-degrees-N or 50-degrees-S) were analyzed for the retrieval of total precipitable water less than 0.5 g cm-2 both over land and ocean surfaces. The results show that total precipitable water from a relatively dry atmosphere could be estimated with high sensitivity from these radiometric measurements. The retrieved values over ocean surface show a decrease toward the polar region as expected. The retrieved total precipitable water over land correlates positively with the aircraft radar altitude. This positive correlation is expected because the aircraft radar altitude provides a measure of atmospheric water vapor burden above the surface. Retrieved high reflectivities over land surface at 90 GHz and 183 GHz are presumably related to snow cover on the ground. This suggests that radiometric measurements at these frequencies could be used to map snow at high-latitude regions. C1 ST SYST CORP,LANHAM,MD. RP WANG, JR (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 975,GREENBELT,MD 20771, USA. NR 19 TC 4 Z9 4 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD DEC PY 1992 VL 31 IS 12 BP 1368 EP 1378 DI 10.1175/1520-0450(1992)031<1368:ROTPWO>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KB863 UT WOS:A1992KB86300002 ER PT J AU WEINBERG, I SWARTZ, CK DREVINSKY, PJ AF WEINBERG, I SWARTZ, CK DREVINSKY, PJ TI CARRIER REMOVAL AND DEFECT BEHAVIOR IN P-TYPE INP SO JOURNAL OF APPLIED PHYSICS LA English DT Note ID SOLAR-CELLS; TRANSIENT SPECTROSCOPY; DAMAGE AB A simple expression, obtained from the rate equation for defect production, was used to relate carrier removal to defect production and hole trapping rates in p-type InP after irradiation by 1-MeV electrons. Specific contributions to carrier removal from defect levels H3, H4, and H5 were determined from combined deep-level transient spectroscopy (DLTS) and measured carrier concentrations. An additional contribution was attributed to one or more defects not observed by the present DLTS measurements. The high trapping rate observed for H5 suggests that this defect, if present in relatively high concentration, could be dominant in p-type InP. C1 PHILLIPS LAB,DIV ELECTR & SOFTWARE,BEDFORD,MA 01731. RP WEINBERG, I (reprint author), NASA,LEWIS RES CTR,CLEVELAND,OH 44135, USA. NR 10 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1992 VL 72 IS 11 BP 5509 EP 5511 DI 10.1063/1.351946 PG 3 WC Physics, Applied SC Physics GA KA932 UT WOS:A1992KA93200075 ER PT J AU CHATFIELD, DC REEVES, MS TRUHLAR, DG DUNECZKY, C SCHWENKE, DW AF CHATFIELD, DC REEVES, MS TRUHLAR, DG DUNECZKY, C SCHWENKE, DW TI COMPLEX GENERALIZED MINIMAL RESIDUAL ALGORITHM FOR ITERATIVE SOLUTION OF QUANTUM-MECHANICAL REACTIVE SCATTERING EQUATIONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID KOHN VARIATIONAL PRINCIPLE; INTEGRAL CROSS-SECTIONS; S-MATRIX VERSION; NONSYMMETRIC LINEAR-SYSTEMS; LOG DERIVATIVE VERSION; BASIS-SET CALCULATIONS; MANY-BODY EXPANSION; CHEMICAL-REACTIONS; HYPERSPHERICAL METHOD; H+H2 REACTION AB A complex GMRes (general zed minimum residual) algorithm is presented and dense systems of linear equations arising in variational basis-set approach s to quantum-mechanical reactive scattering. The examples presented correspond to physical solutions of the Schrodinger equation for the reactions O + HD --> OH + D, D + H-2 --> HD + H, and H + H-2 --> H-2 + H. It is shown that the computational effort for solution with GMRes depends upon both the dimension of the linear system and the total energy of the reaction. In several cases with dimensions in the range 1110-5632, GMRes outperforms the LAPACK direct solver, with speedups for the linear equation solution as large as a factor of 23. In other cases, the iterative algorithm does not converge within a reasonable time. These convergence differences can be correlated with "indices of diagonal dominance," which we define in detail and which are relatively easy to compute. Furthermore, we find that for a given energy, the computational effort for GMRes can vary with dimension as favorably as M1.7, where M is the dimension of the linear system, whereas the computer time for a direct method is approximately proportional to the cube of the dimension of the linear system. C1 UNIV MINNESOTA, INST SUPERCOMP, DEPT CHEM, MINNEAPOLIS, MN 55455 USA. UNIV MINNESOTA, USA, HIGH PERFORMANCE COMP RES CTR, MINNEAPOLIS, MN 55455 USA. KANSAS STATE UNIV AGR & APPL SCI, DEPT CHEM, MANHATTAN, KS 66506 USA. NASA, AMES RES CTR, MOFFETT FIELD, CA 94035 USA. RI schwenke, david/I-3564-2013; Truhlar, Donald/G-7076-2015 OI Truhlar, Donald/0000-0002-7742-7294 NR 81 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1992 VL 97 IS 11 BP 8322 EP 8333 DI 10.1063/1.463402 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KA706 UT WOS:A1992KA70600047 ER PT J AU MARTIN, JML LEE, TJ TAYLOR, PR AF MARTIN, JML LEE, TJ TAYLOR, PR TI AN ACCURATE ABINITIO QUARTIC FORCE-FIELD FOR AMMONIA SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID QUADRATIC CONFIGURATION-INTERACTION; FOURIER-TRANSFORM SPECTRA; ELECTRONIC GROUND-STATE; SPECTROSCOPIC CONSTANTS; VIBRATIONAL-STATES; TRIPLE EXCITATIONS; POTENTIAL FUNCTION; (NH3)-N-14; NH3; MOLECULES AB The quartic force field of ammonia is computed using basis sets of spdf/spd and spdfg/spdf quality and an augmented coupled cluster method. After correcting for Fermi resonance, the computed fundamentals and nu4 overtones agree on average to better than 3 cm-1 with the experimental ones except for nu2. The discrepancy for nu2 is principally due to higher-order anharmonicity effects. The computed omega1, omega3, and omega4 confirm the recent experimental determination by Lehmann and Coy but are associated with smaller error bars. The discrepancy between the computed and experimental omega2 is far outside the expected error range, which is also attributed to higher-order anharmonicity effects not accounted for in the experimental determination. Spectroscopic constants are predicted for a number of symmetric and asymmetric top isotopomers of NH3. C1 LIMBURGS UNIV CENTRUM,DEPT SBG,B-3610 DIEPENBEEK,BELGIUM. UNIV INSTELLING ANTWERP,INST MAT SCI,DEPT CHEM,B-2610 WILRIJK,BELGIUM. ELORET INST,PALO ALTO,CA 94303. RP MARTIN, JML (reprint author), NASA,AMES RES CTR,MAIL STOP RTC 203-3,MOFFETT FIELD,CA 94035, USA. RI Lee, Timothy/K-2838-2012; Martin, Jan/A-7457-2008 OI Martin, Jan/0000-0002-0005-5074 NR 63 TC 120 Z9 121 U1 0 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1992 VL 97 IS 11 BP 8361 EP 8371 DI 10.1063/1.463406 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KA706 UT WOS:A1992KA70600051 ER PT J AU LAU, KM CHANG, FC AF LAU, KM CHANG, FC TI TROPICAL INTRASEASONAL OSCILLATION AND ITS PREDICTION BY THE NMC OPERATIONAL MODEL SO JOURNAL OF CLIMATE LA English DT Article ID VARYING BASIC STATE; RANGE FORECASTS; TIME SCALES; CIRCULATION; CONVECTION; DERF AB In this paper, results are presented of an investigation to study the tropical intraseasonal oscillation (ISO) and its impact on the extended-range forecast in the NMC operational model during Phase II ( 14 December 1986-31 March 1987) of the Dynamical Extended Range Forecast (DERF). Based on principal component analysis of the velocity potential and streamfunction, evidence was found of tropical-extratropical interaction associated with the ISO. The NMC model possesses significant forecast skills for the principal streamfunction and velocity potential modes up to the first ten days. Results of the error growth analysis suggest that the principal modes of velocity potential have large initial errors comparable to the model random errors. By comparison, the initial errors in the streamfunction are much smaller. The error growth for both tropical and extratropical modes are found to be significantly suppressed during periods of strong ISO relative to periods of weak ISO. During strong ISO, a reduction of forecast error, implying a recovery of forecast skill, is also found at about three weeks into the forecast. This is presumably due to the oscillatory nature of the ISO. The overall results suggest that the forecast skill of ISO and of low-frequency extratropical modes may be considerably enhanced during a special period of DERF when the ISO was strong. The increase in extratropical forecast skill is likely due to (a) the model's ability to better capture ISO signals in the tropics and (b) the increased coupling between the tropics and extratropics during periods of strong ISO. However, because of the limited data, the applicability of the present results to a more general case needs to be ascertained by further studies. C1 APPL RES CORP,LANDOVER,MD. RP LAU, KM (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GODDARD LAB ATMOSPHERES,CODE 913,GREENBELT,MD 20771, USA. RI Lau, William /E-1510-2012 OI Lau, William /0000-0002-3587-3691 NR 20 TC 43 Z9 43 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD DEC PY 1992 VL 5 IS 12 BP 1365 EP 1378 DI 10.1175/1520-0442(1992)005<1365:TIOAIP>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KZ876 UT WOS:A1992KZ87600001 ER PT J AU KOSTER, RD SUAREZ, MJ AF KOSTER, RD SUAREZ, MJ TI A COMPARATIVE-ANALYSIS OF 2 LAND SURFACE HETEROGENEITY REPRESENTATIONS SO JOURNAL OF CLIMATE LA English DT Article ID MODELS AB Two contrasting representations of land surface variability used in general circulation models (GCMs) are compared through an analysis of their corresponding surface energy balance equations. In one representation (the ''mixture'' approach), different vegetation types are assumed to be homogeneously mixed over a grid square, so that the GCM atmosphere sees near-surface conditions pertaining to the mixture only. In the second representation (the ''mosaic'' approach), different vegetation types are viewed as separate ''tiles'' of a grid-square ''mosaic,'' and each tile interacts with the atmosphere independently. The mosaic approach is computationally simpler and in many ways more flexible than the mixture approach. Analytical solutions to the linearized energy balance equations and numerical solutions to the nonlinear equations both demonstrate that the mixture strategy, when applied to two coexisting vegetation types that differ only in canopy transpiration resistance, promotes both total turbulent flux and latent heat flux relative to the mosaic strategy. The effective differences between the strategies, however, are small over a wide range of conditions. In particular, the strategies are effectively equivalent when the transpiration resistances of the different vegetation types are of the same order of magnitude. RP KOSTER, RD (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HYDROL SCI BRANCH,CODE 974,GREENBELT,MD 20771, USA. RI Koster, Randal/F-5881-2012 OI Koster, Randal/0000-0001-6418-6383 NR 10 TC 106 Z9 110 U1 1 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD DEC PY 1992 VL 5 IS 12 BP 1379 EP 1390 DI 10.1175/1520-0442(1992)005<1379:ACAOTL>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KZ876 UT WOS:A1992KZ87600002 ER PT J AU TSELIOUDIS, G ROSSOW, WB RIND, D AF TSELIOUDIS, G ROSSOW, WB RIND, D TI GLOBAL PATTERNS OF CLOUD OPTICAL-THICKNESS VARIATION WITH TEMPERATURE SO JOURNAL OF CLIMATE LA English DT Article ID SOLAR-RADIATION MEASUREMENTS; GENERAL-CIRCULATION MODEL; EFFECTIVE PARTICLE RADIUS; LIQUID WATER-CONTENT; AIRCRAFT OBSERVATIONS; MARINE STRATOCUMULUS; BOUNDARY-LAYER; CLIMATE; FEEDBACK; MICROPHYSICS AB The international Satellite Cloud Climatology Project (ISCCP) dataset is used to correlate variations of cloud optical thickness and cloud temperature in today's atmosphere. The analysis focuses on low clouds in order to limit the importance of changes in cloud vertical extent, particle size, and water phase. Coherent patterns of change are observed on several time and space scales. On the planetary scale, clouds in colder, higher latitudes are found to be optically thicker than clouds in warmer, lower latitudes. On the seasonal scale, winter clouds are, for the most part, optically thicker than summer clouds. The logarithmic derivative of cloud optical thickness with temperature is used to describe the sign and magnitude of the optical thickness-temperature correlation. The seasonal, latitudinal, and day-to-day variations of this relation are examined for Northern Hemisphere clouds in 1984. The analysis is done separately for clouds over land and ocean. In cold continental clouds, optical thickness increases with temperature, consistent with the temperature variation of the adiabatic cloud water content. In warm continental and in almost all maritime clouds, however, optical thickness decreases with temperature. The behavior of the optical thickness-temperature relation is usually, though not always, the same whether the temperature variations are driven by seasonal, latitudinal, or day-to-day changes. Important exceptions are noted. Some explanations for the observed behavior are proposed. C1 COLUMBIA UNIV, DEPT GEOL SCI, NEW YORK, NY 10027 USA. RP NASA, GODDARD INST SPACE STUDIES, 2880 BROADWAY, NEW YORK, NY 10025 USA. RI Rossow, William/F-3138-2015 NR 43 TC 78 Z9 79 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD DEC PY 1992 VL 5 IS 12 BP 1484 EP 1497 DI 10.1175/1520-0442(1992)005<1484:GPOCOT>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KZ876 UT WOS:A1992KZ87600009 ER PT J AU HOPKINS, WD WASHBURN, DA BERKE, L WILLIAMS, M AF HOPKINS, WD WASHBURN, DA BERKE, L WILLIAMS, M TI BEHAVIORAL ASYMMETRIES OF PSYCHOMOTOR PERFORMANCE IN RHESUS-MONKEYS (MACACA-MULATTA) - A DISSOCIATION BETWEEN HAND PREFERENCE AND SKILL SO JOURNAL OF COMPARATIVE PSYCHOLOGY LA English DT Article ID LATERALITY; HANDEDNESS; SPECIALIZATION; CHIMPANZEES; EVOLUTION; PRIMATES; HUMANS; TASKS AB Hand preferences were recorded for 35 rhesus monkeys (Macaca mulatta) as they manipulated a joystick in response to 2 computerized tasks. These preferences were then used to contrast 8 left- and 10 right-handed subjects on performance measures of hand skill. Individual hand preferences were found, but no significant population asymmetry was observed across the sample. However, the performance data reveal substantial benefits of right-handedness for joystick manipulation, as this group of monkeys mastered the 2 psychomotor tasks significantly faster than did their left-handed counterparts. The data support earlier reports of a right-hand advantage for joystick manipulation and also support the importance of distinguishing between hand preference and manual performance in research on functional asymmetries. C1 GEORGIA STATE UNIV,DEPT PSYCHOL,LANGUAGE RES CTR,ATLANTA,GA 30303. BIONET CORP,AMES RES CTR,MOFFETT FIELD,CA. FU DS NIH HHS [NINDS-29574]; NICHD NIH HHS [HD-06016] NR 29 TC 28 Z9 28 U1 0 U2 5 PU AMER PSYCHOLOGICAL ASSOC PI WASHINGTON PA 750 FIRST ST NE, WASHINGTON, DC 20002-4242 SN 0735-7036 J9 J COMP PSYCHOL JI J. Comp. Psychol. PD DEC PY 1992 VL 106 IS 4 BP 392 EP 397 DI 10.1037/0735-7036.106.4.392 PG 6 WC Behavioral Sciences; Psychology; Psychology, Multidisciplinary; Zoology SC Behavioral Sciences; Psychology; Zoology GA JY565 UT WOS:A1992JY56500010 PM 1451422 ER PT J AU BIGELOW, CA AF BIGELOW, CA TI THE EFFECTS OF UNEVEN FIBER SPACING ON THERMAL RESIDUAL-STRESSES IN A UNIDIRECTIONAL SCS-6/TI-15-3 LAMINATE SO JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH LA English DT Article DE COMPOSITES; FREE SURFACE; FIBER VOLUME FRACTION; MICROMECHANICS; MATRIX CRACKS; 3-DIMENSIONAL FINITE ELEMENTS AB High residual stresses develop in SCS-6/Ti-15-3 composites during cooldown from the fabrication temperature; these residual stresses can affect the behavior of the composite. Discrete fiber-matrix finite element models were used to study the residual stresses caused by the temperature change during the fabrication process, including the effects of uneven fiber spacing, the free surface, and increased fiber volume fractions. Results showed that the calculated stress distributions in a surface ply were significantly different from those calculated for an interior ply. However, the stresses were identical for all subsurface plies. In an interior ply, for uneven fiber spacing less than 0.042 mm, the maximum hoop stress was calculated to occur between fibers within a ply and increased as the fiber spacing decreased. For interior plies, the trend in the calculated maximum hoop stress between fibers within a ply agreed with the observed radial cracking between fibers. For the case of touching fibers, the analysis predicted tensile radial stresses at the fiber-matrix interface, which could lead to fiber-matrix debonding during cooldown. Identical trends were predicted for uneven fiber spacing in surface plies with slightly greater values of peak stresses. The calculations for increasing fiber volume fractions were similar to the calculated results for decreasing the fiber spacing between two adjacent fibers within a ply. The results indicate that matrix cracking and fiber-matrix debonding are more likely to occur during processing for laminates with higher fiber volume fractions. RP BIGELOW, CA (reprint author), NASA,LANGLEY RES CTR,MS 188E,HAMPTON,VA 23681, USA. NR 7 TC 27 Z9 27 U1 0 U2 1 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0884-6804 J9 J COMPOS TECH RES JI J. Compos. Technol. Res. PD WIN PY 1992 VL 14 IS 4 BP 211 EP 220 PG 10 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA KE752 UT WOS:A1992KE75200002 ER PT J AU HILLBERRY, BM JOHNSON, WS AF HILLBERRY, BM JOHNSON, WS TI PREDICTION OF MATRIX FATIGUE CRACK INITIATION IN NOTCHED SCS-6/TI-15-3 METAL MATRIX COMPOSITES SO JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH LA English DT Article DE METAL MATRIX COMPOSITES; EFFECTIVE STRAIN; RESIDUAL THERMAL STRESS; STRESS CONCENTRATION AB Several lay-ups of SCS-6/Ti-15-3 metal matrix composites were tested in either a center hole or a double-edge-notched geometry. At different cyclic stress levels, the number of cycles required to initiate a matrix fatigue crack at the notch was recorded. A strain-life fatigue curve was developed for the Ti-15-3 matrix material. A strain-life fatigue analysis method was developed that incorporates a modified Smith, Watson, and Topper effective strain parameter to account for local stress concentration at the notch tip and thermal residual stresses in the matrix material. This analysis method was used to predict the number of cycles required for matrix crack initiation at the notches. The predictions were in good agreement with the experimental data. C1 NASA,LANGLEY RES CTR,DIV MAT,HAMPTON,VA 23665. RP HILLBERRY, BM (reprint author), PURDUE UNIV,SCH MECH ENGN,W LAFAYETTE,IN 47907, USA. NR 9 TC 13 Z9 13 U1 1 U2 2 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0884-6804 J9 J COMPOS TECH RES JI J. Compos. Technol. Res. PD WIN PY 1992 VL 14 IS 4 BP 221 EP 224 PG 4 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA KE752 UT WOS:A1992KE75200003 ER PT J AU SRINIVASAN, K COATS, TW HINKLEY, JA AF SRINIVASAN, K COATS, TW HINKLEY, JA TI SHEAR FAILURE AND IMPACT RESISTANCE IN GRAPHITE FIBER LAMINATES SO JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH LA English DT Article DE COMPOSITE MATERIALS; GRAPHITE COMPOSITES; EPOXY RESINS; THERMOPLASTIC RESINS; IMPACT DAMAGE; COMPRESSIVE STRENGTH; DAMAGE TOLERANCE; BENDING TESTS AB The multispan beam (MSB) test was evaluated as a predictor of damage resistance and damage tolerance in quasi-isotropic graphite laminates. Materials studied were five commercial prepreg systems using high-strain and intermediate-modulus carbon fibers, as well as an amorphous thermoplastic system prepared in-house. Failure loads and displacements in the MSB tests showed little rate dependence. Values of compressive strength after a standard low-velocity impact (compression after impact [CAI]) correlated fairly well with the MSB results. C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP SRINIVASAN, K (reprint author), OLD DOMINION UNIV,NORFOLK,VA 23529, USA. NR 14 TC 2 Z9 2 U1 0 U2 2 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0884-6804 J9 J COMPOS TECH RES JI J. Compos. Technol. Res. PD WIN PY 1992 VL 14 IS 4 BP 231 EP 234 PG 4 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA KE752 UT WOS:A1992KE75200005 ER PT J AU HUI, WH LOH, CY AF HUI, WH LOH, CY TI A NEW LAGRANGIAN METHOD FOR STEADY SUPERSONIC-FLOW COMPUTATION .3. STRONG SHOCKS SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Note C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP HUI, WH (reprint author), UNIV WATERLOO,DEPT APPL MATH,WATERLOO N2L 3G1,ONTARIO,CANADA. NR 9 TC 18 Z9 18 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD DEC PY 1992 VL 103 IS 2 BP 465 EP 471 DI 10.1016/0021-9991(92)90416-V PG 7 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA KD206 UT WOS:A1992KD20600021 ER PT J AU SEARS, B NARAYANAN, R ANDERSON, TJ FRIPP, AL AF SEARS, B NARAYANAN, R ANDERSON, TJ FRIPP, AL TI CONVECTION OF TIN IN A BRIDGMAN SYSTEM .1. FLOW CHARACTERIZATION BY EFFECTIVE DIFFUSIVITY MEASUREMENTS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID CYLINDRICAL FLUID LAYER; TURBULENT CONVECTION; THERMOCONVECTIVE INSTABILITY; TRANSITION; CONFIGURATIONS; GROWTH AB An electrochemical titration method was used to investigate the dynamic states in a cylindrical layer of convecting tin. The liquid tin was contained in a cell, with curved boundaries made of quartz and flat boundaries made of a solid state electrolyte - yttria-stabilized zirconia (YSZ). The electrolyte acted as a window through which a trace amount of oxygen could be pumped in or out by the application of a constant voltage. The concentration at the YSZ interface was monitored by operating the electrochemical cell in the galvanic mode. Experimentally determined effective diffusivities of oxygen were compared with the molecular diffusivity. Dynamic states in the convective flow were thus inferred. Temperature measurements were simultaneously made in order to identify the onset of oscillations from a steady convective regime. The experiments were conducted for two different aspect ratios for various imposed temperature gradients and two different orientations with respect to gravity. Transcritical states were identified and comparison to two-dimensional numerical models were made. C1 UNIV FLORIDA,DEPT CHEM ENGN,GAINESVILLE,FL 32611. NASA,LANGLEY RES CTR,HAMPTON,VA 23665. NR 19 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1992 VL 125 IS 3-4 BP 404 EP 414 DI 10.1016/0022-0248(92)90278-Q PG 11 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KF738 UT WOS:A1992KF73800002 ER PT J AU SEARS, B FRIPP, AL DEBNAM, WJ WOODELL, GA ANDERSON, TJ NARAYANAN, R AF SEARS, B FRIPP, AL DEBNAM, WJ WOODELL, GA ANDERSON, TJ NARAYANAN, R TI CONVECTION OF TIN IN A BRIDGMAN SYSTEM .2. AN ELECTROCHEMICAL METHOD FOR DETECTING FLOW REGIMES SO JOURNAL OF CRYSTAL GROWTH LA English DT Article AB An ampoule was designed in order to obtain local flow behavior of the flow fields for convection of tin in a vertical Bridgman configuration. Multiple electochemical cells were located along the periphery of the ampoule. Oxygen was titrated into the ampoule at one of the cell locations using a potentiostat and the concentration of oxygen was monitored at the other cell locations by operating the cells in a galvanic mode. Onset of oscillations were detected by means of thermocouples. We concluded that the flows are generally three dimensional for an aspect ratio of 5. Results on oscillations concurred with those of earlier workers. Suggestions for improved designs were made. C1 UNIV FLORIDA,DEPT CHEM ENGN,GAINESVILLE,FL 32611. NASA,LANGLEY RES CTR,HAMPTON,VA 23665. NR 5 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1992 VL 125 IS 3-4 BP 415 EP 419 DI 10.1016/0022-0248(92)90279-R PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KF738 UT WOS:A1992KF73800003 ER PT J AU CHU, JS LONG, SR PHILLIPS, OM AF CHU, JS LONG, SR PHILLIPS, OM TI MEASUREMENTS OF THE INTERACTION OF WAVE GROUPS WITH SHORTER WIND-GENERATED WAVES SO JOURNAL OF FLUID MECHANICS LA English DT Article ID SWELL AB Fields of statistically steady wind-generated waves produced in the NASA-Wallops wind wave facility, were perturbed by the injection of groups of longer waves with various slopes, mechanically generated at the upwind end of the tank. The time histories of the surface displacements were measured at four fetches in ensembles consisting of 100 realizations of each set of experimental conditions, the data being stored and analysed digitally. The overall interaction was found to have four distinct phases. (i) When the longer waves overtake the pre-existing wind-generated waves, during the first half of the group where successive crests are increasing in amplitude, vigorous wave breaking near the crests reduces the energy density and zeta2BAR in the wind waves while straining by the orbital velocities of the group reduces their wave-lengths near the crests; the 'significant slope' 2pi(zeta2BAR)1/2/lambda at the crests is found to be very nearly constant and equal to the initial, undisturbed value. After the maximum wave of the group has passed, breaking appears to virtually cease but the earlier energy loss results in suppression of the short waves. The overall suppression by a group of waves is significantly less than that measured by Mitsuyasu (1966) and Phillips & Banner (1974) in a continuous train of waves whose slope is equal to the maximum in the group. A simple description of this phase of the interaction, involving constant significant slope of the breaking waves over the leading half of the group and conservation of action thereafter, gives suppression ratios close to those measured. (ii) Once the group has passed, the surface is much smoother and the waves begin to regenerate under the continued influence of the wind but at rates considerably slower than those suggested by Plant's formula, using the averaged value of u*. This is qualitatively consistent with a locally reduced surface stress as the wind blows from rougher water well behind the group to the smoother surface immediately behind it. (iii) The regeneration is interrupted by the arrival of a wave energy,front moving down the tank, across which the energy density rises abruptly to values up to six times greater than in the undisturbed field. At the same time, the dominant frequencies just behind the wave energy front are lower than in the initial field, and the significant slope (zeta2BAR)1/2 sigma2/g is, within experimental uncertainty, again identical to that in the initial field. The front was found to propagate notably faster than the appropriate group velocity (g/2sigma) and it is suggested that this is the combined result of dispersion, nonlinearity and wind amplification, together with wind-induced drift in the tank. Finally, (iv) the energy density gradually subsides and the dominant wave frequency increases as the wind waves relax towards their undisturbed state, the relaxation seeming to be essentially complete when energy packets arriving at a point have originated at the upwind end of the tank, rather than at the wave energy front. C1 NASA,GODDARD SPACE FLIGHT CTR,WALLOPS FLIGHT FACIL,WALLOPS ISL,VA 23337. RP CHU, JS (reprint author), JOHNS HOPKINS UNIV,DEPT EARTH & PLANETARY SCI,BALTIMORE,MD 21218, USA. RI Long, Steven/D-7248-2012 NR 11 TC 10 Z9 10 U1 2 U2 2 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD DEC PY 1992 VL 245 BP 191 EP 210 DI 10.1017/S0022112092000417 PG 20 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KE718 UT WOS:A1992KE71800010 ER PT J AU GOLDSTEIN, ME LEE, SS AF GOLDSTEIN, ME LEE, SS TI FULLY COUPLED RESONANT-TRIAD INTERACTION IN AN ADVERSE-PRESSURE-GRADIENT BOUNDARY-LAYER SO JOURNAL OF FLUID MECHANICS LA English DT Article ID FREE SHEAR-LAYER; NONLINEAR EVOLUTION; OBLIQUE WAVES; DISTURBANCES; INSTABILITY; SEPARATION; TRANSITION AB The nonlinear resonant-triad interaction, proposed by Raetz (1959), Craik (1971), and others for a Blasius boundary layer, is analysed here for an adverse-pressure-gradient boundary layer. We assume that the adverse pressure gradient is in some sense weak and, therefore, that the instability growth rate is small. This ensures that there is a well-defined critical layer located somewhere within the flow and that the nonlinear interaction is effectively confined to that layer. The initial interaction is of the parametric resonance type, even when the modal amplitudes are all of the same order. This means that the oblique instability waves exhibit faster than exponential growth and that the growth rate of the two-dimensional mode remains linear. However, the interaction and the resulting growth rates become fully coupled, once oblique-mode amplitudes become sufficiently large, but the coupling terms are now quartic, rather than quadratic as in the Craik (1971) analysis. More importantly, however, new nonlinear interactions, which were not present in the Craik-type analyses, now come into play. These interactions eventually have a dominant effect on the instability wave development. C1 SVERDRUP TECHNOL INC,LEWIS RES CTR GRP,CLEVELAND,OH 44135. RP GOLDSTEIN, ME (reprint author), NASA,LEWIS RES CTR,CLEVELAND,OH 44135, USA. NR 29 TC 46 Z9 47 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD DEC PY 1992 VL 245 BP 523 EP 551 DI 10.1017/S0022112092000570 PG 29 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KE718 UT WOS:A1992KE71800026 ER PT J AU PIERCE, FJ SHIN, J AF PIERCE, FJ SHIN, J TI THE DEVELOPMENT OF A TURBULENT JUNCTION VORTEX SYSTEM SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID MEAN FLOW STRUCTURE; HORSESHOE VORTEX AB The growth and development of a horseshoe vortex system in an incompressible, three-dimensional turbulent junction flow were investigated experimentally. A streamlined cylinder mounted with its axis normal to a flat surface was used to generate the junction vortex flow. The flow environment was characterized by a body Reynolds number of 183,000, based on the leading edge diameter of the streamlined cylinder. The study included surface flow visualizations, surface pressure measurements, and mean flow measurements of total pressure, static pressure, and velocity distributions in three planes around the base of the streamlined cylinder, and in two planes in the wake flow. Some characterizations of vortex properties based on the measured mean cross-flow velocity components are presented. The results show the presence of a single large, dominant vortex, with strong evidence of a very small corner vortex in the junction between the cylinder and the flat surface. The center of the dominant vortex drifts away from both the body and the flat surface as the flow develops along and downstream of the body. The growth and development of the core of the large, dominant vortex are documented. C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. RP PIERCE, FJ (reprint author), VIRGINIA POLYTECH INST & STATE UNIV,DEPT MECH ENGN,BLACKSBURG,VA 24061, USA. NR 20 TC 20 Z9 21 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD DEC PY 1992 VL 114 IS 4 BP 559 EP 565 DI 10.1115/1.2910068 PG 7 WC Engineering, Mechanical SC Engineering GA KF653 UT WOS:A1992KF65300012 ER PT J AU CLELAND, JG KORNFELD, DM AF CLELAND, JG KORNFELD, DM TI OPTIMIZATION OF THE PARAMETERS FOR A ROTATING, MIXED-PHASE REACTOR SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID CENTRIFUGAL SEPARATION AB The motion of small, monodisperse particles in fluid was studied in a horizontal, cylindrical container rotating about its axis. One instigation for the study was the common requirement for mixed-phase, chemical or biological reactors to maintain particles in suspension for extended periods. A cylindrical, rotating reactor can allow long-term particle suspension without particle collisions and resulting agglomeration. The purpose of this study was to verify parametric effects and optimize the time of particle suspension. The theoretical and experimental results were obtained for inert, constant-diameter particle of nearly neutral buoyancy. The centrifugal buoyancy and gravitation terms were both included in the equations of motion. Laser illumination, photography and computer imaging were used to measure experimental particle concentration. C1 NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,HUNTSVILLE,AL 35812. RP CLELAND, JG (reprint author), RES TRIANGLE INST,RES TRIANGLE PK,NC 27709, USA. NR 9 TC 1 Z9 1 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD DEC PY 1992 VL 114 IS 4 BP 616 EP 620 DI 10.1115/1.2910075 PG 5 WC Engineering, Mechanical SC Engineering GA KF653 UT WOS:A1992KF65300019 ER PT J AU MOSES, SL CORONITI, FV GREENSTADT, EW TSURUTANI, BT AF MOSES, SL CORONITI, FV GREENSTADT, EW TSURUTANI, BT TI OBSERVATIONS OF PLASMA-WAVES IN THE SOLAR-WIND INTERACTION REGION OF COMET GIACOBINI-ZINNER AT HIGH TIME RESOLUTION SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HYDROMAGNETIC-WAVES; ELECTRON FORESHOCK; ION PICKUP; ENVIRONMENT; UPSTREAM; HALLEY AB High-time-resolution spectra of plasma wave emissions detected in the interaction region of comet Giacobini-Zinner with the solar wind reveal a wave phenomenology much more complicated than first reported. Spectra often exhibit three or more independent peaks, which become more prominent the deeper into the interaction region the spacecraft traversed. The main peaks correspond to whistler emissions below the electron cyclotron frequency, a midfrequency peak near the maximum Doppler shift frequency for waves with klambda(D) = 1, a high-frequency peak above the Doppler shift maximum frequency, and electron plasma oscillations at the plasma frequency. Similar multipeaked spectra are also observed downstream from weak shocks at Earth, which suggests that the plasma wave generation mechanisms responsible need not require particle populations created by photoionization. C1 JET PROP LAB,PASADENA,CA 91109. RP MOSES, SL (reprint author), TRW CO INC,SPACE & TECHNOL GRP,1 SPACE PK,R1-2020,REDONDO BEACH,CA 90278, USA. NR 17 TC 0 Z9 0 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19157 EP 19162 DI 10.1029/92JA01601 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800006 ER PT J AU HUDDLESTON, DE COATES, AJ JOHNSTONE, AD AF HUDDLESTON, DE COATES, AJ JOHNSTONE, AD TI QUASI-LINEAR VELOCITY SPACE DIFFUSION OF HEAVY COMETARY PICKUP IONS ON BISPHERICAL DIFFUSION CHARACTERISTICS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PITCH ANGLE DIFFUSION; WATER-GROUP IONS; HYDROMAGNETIC WAVE EXCITATION; HALLEY BOW SHOCK; SOLAR-WIND; NEWBORN IONS; GIACOBINI-ZINNER; MAGNETIC-FIELD; ALFVEN WAVES; TURBULENCE AB We consider an ion transport equation describing the source, convection, adiabatic acceleration and quasi-linear velocity diffusion of cometary pickup ions. The equation is solved numerically along solar wind plasma flow lines for the environment of comet Halley, to obtain distributions at positions on the Giotto spacecraft trajectory which may be compared with observations. We use realistic input models for the observed spectrum of upstream and downstream propagating wave turbulence and for the ion source and mass loading of the solar wind. The ion resonance condition is not approximated in the diffusion term and we obtain full two-dimensional (pitch angle and velocity) numerical distributions which show pitch angle scattering about the wave scattering centers at +/-V(A) where V(A) is the Alfven wave speed in the solar wind frame. Peak ion phase-space densities approximately follow the bispherical shell geometry. The energy distributions F(v) agree well with Giotto observations at lower v but in the high-energy tail there is evidence possibly for the first-order Fermi acceleration mechanism taking place in the comet Halley foreshock region. C1 UCL, MULLARD SPACE SCI LAB, DORKING RH5 6NT, SURREY, ENGLAND. RP HUDDLESTON, DE (reprint author), JET PROP LAB, 4800 OAK GROVE DR, MS 169-506, PASADENA, CA 91109 USA. RI Coates, Andrew/C-2396-2008 OI Coates, Andrew/0000-0002-6185-3125 NR 51 TC 24 Z9 24 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19163 EP 19174 DI 10.1029/92JA01873 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800007 ER PT J AU ORLOWSKI, DS RUSSELL, CT LEPPING, RP AF ORLOWSKI, DS RUSSELL, CT LEPPING, RP TI WAVE PHENOMENA IN THE UPSTREAM REGION OF SATURN SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EARTHS BOW SHOCK; ENERGETIC IONS DOWNSTREAM; AMPLITUDE MHD WAVES; LOW-FREQUENCY WAVES; ONE-HERTZ WAVES; SOLAR-WIND; FORESHOCK REGION; PACKETS; VENUS; DISTRIBUTIONS AB The magnetic field data returned from the Voyager 1 and 2 transit through the upstream region of Saturn have been examined from 0.1 mHz to 0.25 Hz to search for the signatures of waves associated with both the electron and ion foreshocks. In contrast to the Earth, in the ion foreshock of Saturn we find two distinct bands of wave activity at frequencies around 0.5 and 2-mHz in the spacecraft frame. These two waves differ considerably in their properties. The 0.5-mHz waves are right handed, strongly elliptically polarized, while the 2-mHz waves are elliptically or circularly polarized in the left-handed sense. These two different waves may be associated with two different backstreaming particle distributions, possibly those reflected from the shock and those leaking from the hot magnetosheath. We also observe right-hand elliptically polarized upstream waves propagating obliquely to the magnetic field at frequencies between 90 and 150 mHz, which are above the proton gyrofrequency in the spacecraft frame. The frequency of these waves appears to be dependent on the interplanetary magnetic field orientation. Such dependence is characteristic of the 1-Hz waves at Earth. Discrete wave packets associated with shocklets are for the first time observed in the foreshock of an outer planet. C1 NASA, GODDARD SPACE FLIGHT CTR, GREENBELT, MD 20771 USA. RP UNIV CALIF LOS ANGELES, INST GEOPHYS & PLANETARY PHYS, 405 HILGARD AVE, LOS ANGELES, CA 90024 USA. NR 57 TC 29 Z9 30 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19187 EP 19199 DI 10.1029/92JA01461 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800009 ER PT J AU PEDERSEN, BM LECACHEUX, A ZARKA, P AUBIER, MG KAISER, ML DESCH, MD AF PEDERSEN, BM LECACHEUX, A ZARKA, P AUBIER, MG KAISER, ML DESCH, MD TI PHENOMENOLOGY OF NEPTUNE RADIO EMISSIONS OBSERVED BY THE VOYAGER PLANETARY RADIO ASTRONOMY EXPERIMENT SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID RING PLANE; JUPITER; MAGNETOSPHERE; POLARIZATION; IMPACTS; URANUS; SATURN; GRAIN AB The Neptune flyby in 1989 added a new planet to the known number of magnetized planets generating nonthermal radio emissions. We review the Neptunian radio emission morphology as observed by the planetary radio astronomy experiment on board Voyager 2 during a few weeks before and after closest approach. We present the characteristics of the two observed recurrent main components of the Neptunian kilometric radiation, i.e., the ''smooth'' and the ''bursty'' emissions, and we describe the many specific features of the radio spectrum during closest approach. C1 OBSERV PARIS,CNRS,URA 324,F-92195 MEUDON,FRANCE. NASA,GODDARD SPACE FLIGHT CTR,EXTRATERR PHYS LAB,GREENBELT,MD 20771. UNIV PARIS 06,PARIS,FRANCE. NR 32 TC 6 Z9 6 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19201 EP 19211 DI 10.1029/92JA01546 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800010 ER PT J AU FITZENREITER, RJ OGILVIE, KW AF FITZENREITER, RJ OGILVIE, KW TI HEAT-FLUX DROPOUTS IN THE SOLAR-WIND AND COULOMB SCATTERING EFFECTS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID VELOCITY DISTRIBUTION-FUNCTIONS; ELECTRON-DISTRIBUTION FUNCTIONS; HELIOS PLASMA-EXPERIMENT; GLOBAL PROCESSES AB Measurements of solar wind electrons at ISEE 3 located 0.01 AU upstream from the Earth (McComas et al., 1989) indicate periods of time when the flux of antisunward suprathermal electrons decreases suddenly, leaving the velocity distribution nearly isotropic and causing the solar wind heat flux to drop. These heat flux dropouts (HFDs) are usually found in regions of increased plasma density and decreased electron temperature, and they are associated with sector boundaries. It has been suggested that HFDs may be due either to disconnection from the Sun of the magnetic flux tube in which they are found, or to enhanced Coulomb scattering of halo electrons in transit from the Sun to the Earth. Using the vector electron spectrometer on ISEE 1, we have found eight intervals of greatly reduced heat flux which appear to be associated with HFDs at ISEE 3. Five of the eight events were delayed by an appropriate convection time and had approximately the same duration as the corresponding ISEE 3 event. The onset times for the other three intervals of reduced heat flux could not be determined in the ISEE 1 data. Other events from the ISEE 3 set were not observed because ISEE 1 either was not in the solar wind or was inside the foreshock, which obscured the HFD identification. Velocity distributions during HFDs at ISEE 1 show that the depletion of halo electrons traveling away from the Sun is most pronounced in the 100-eV range, while there is essentially no depletion in the 1-keV range, and that in four cases the magnitude of the halo depletion and its upper velocity limit both depend on the density increase in the HFD. These results are shown to be in agreement with the v-3 dependence of the Coulomb collision frequency. Thus we conclude that Coulomb scattering effects play a substantial role in at least some heat flux dropout events. RP FITZENREITER, RJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,EXTRATERR PHYS LAB,CODE 692,GREENBELT,MD 20771, USA. NR 11 TC 12 Z9 12 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19213 EP 19219 DI 10.1029/92JA00432 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800011 ER PT J AU MACWAN, SE AF MACWAN, SE TI A DETERMINATION OF TWISTING OF THE EARTHS MAGNETOTAIL AT DISTANCES 115-220 RE - ISEE 3 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETIC-FIELD; TAIL LOBES; GEOTAIL; MAGNETOSPHERE; ASYMMETRIES AB Observations from magnetic field and plasma experiments on ISEE 3 are used to identify and to analyze 16 crossings of the distant magnetotail neutral sheet. Four methods of analyses have been employed to measure the extent of the magnetotail twisting, which is found to be much greater than what was previously observed or, the theoretically inferred twist. A twist of more than 90-degrees has frequently been observed on both open and closed magnetic field lines. In addition, the location of the magnetic neutral line of the magnetotail has been found to move over the distance interval of 115 to 220 Earth radii. Some features of these results suggest that a modification of the present solar wind-geomagnetic field interaction model may be needed. C1 APPL RES CORP,LANDOVER,MD. RP MACWAN, SE (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 685-3,GREENBELT,MD 20771, USA. NR 30 TC 13 Z9 13 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19239 EP 19249 DI 10.1029/91JA03145 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800013 ER PT J AU PULKKINEN, TI BAKER, DN PELLINEN, RJ BUCHNER, J KOSKINEN, HEJ LOPEZ, RE DYSON, RL FRANK, LA AF PULKKINEN, TI BAKER, DN PELLINEN, RJ BUCHNER, J KOSKINEN, HEJ LOPEZ, RE DYSON, RL FRANK, LA TI PARTICLE SCATTERING AND CURRENT SHEET STABILITY IN THE GEOMAGNETIC TAIL DURING THE SUBSTORM GROWTH-PHASE SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETOSPHERIC MAGNETIC-FIELD; TEARING MODE; QUANTITATIVE MODELS; EARTH MAGNETOTAIL; HIGH-LATITUDES; PLASMA SHEET; INSTABILITY; SPACECRAFT; DISRUPTION; DIVERSION AB The degree of pitch angle scattering and chaotization of various particle populations in the geomagnetic tail during the substorm growth phase is studied by utilizing the Tsyganenko 1989 magnetic field model. A temporally evolving magnetic field model for the growth phase is constructed by enhancing the near-Earth currents and thinning the current sheet from the values given by the static Tsyganenko model. Changing the field geometry toward an increasingly taillike configuration leads to pitch angle scattering of particles whose Larmor radii become comparable to the field line radius of curvature. Several different cases representing substorms with varying levels of magnetic disturbance have been studied. In each case, the field development during the growth phase leads to considerable scattering of the thermal electrons relatively close to the Earth. The current sheet regions where the electron motion is chaotic are magnetically mapped to the ionosphere and compared with low-altitude measurements of electron precipitation. ne chaotization of the thermal electron population occurs within a few minutes of the substorm onset, and the ionospheric mappings of the chaotic regions in the equatorial plane compare well with the region of brightening auroras. Even though the temporal evolution of the complex plasma system cannot be self-consistently described by the temporal evolution of the empirical field model, these models can provide the most accurate estimates of the field parameters for tail stability calculations. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. MAX PLANCK INST EXTRATERR PHYS,AUSSENSTELLUNG BERLIN,O-1199 BERLIN,GERMANY. UNIV IOWA,DEPT PHYS & ASTRON,IOWA CITY,IA 52242. RP PULKKINEN, TI (reprint author), FINNISH METEOROL INST,POB 503,SF-00101 HELSINKI,FINLAND. RI Buechner, Joerg/B-1213-2009; Pulkkinen, Tuija/D-8403-2012; Koskinen, Hannu/B-4971-2017; OI Pulkkinen, Tuija/0000-0002-6317-381X; Koskinen, Hannu/0000-0003-3839-6461; Lopez, Ramon/0000-0001-5881-1365 NR 43 TC 114 Z9 115 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19283 EP 19297 DI 10.1029/92JA01189 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800016 ER PT J AU SAUNDERS, MA FREEMAN, MP SOUTHWOOD, DJ COWLEY, SWH LOCKWOOD, M SAMSON, JC FARRUGIA, CJ HUGHES, TJ AF SAUNDERS, MA FREEMAN, MP SOUTHWOOD, DJ COWLEY, SWH LOCKWOOD, M SAMSON, JC FARRUGIA, CJ HUGHES, TJ TI DAYSIDE IONOSPHERIC CONVECTION CHANGES IN RESPONSE TO LONG-PERIOD INTERPLANETARY MAGNETIC-FIELD OSCILLATIONS - DETERMINATION OF THE IONOSPHERIC PHASE-VELOCITY SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HIGH TIME RESOLUTION; FLUX-TRANSFER EVENTS; NORTH-SOUTH COMPONENT; PLASMA CONVECTION; PARAMETER CORRELATIONS; EARTHS MAGNETOPAUSE; ELECTRIC-FIELDS; HIGH-LATITUDES; AURORAL OVAL; SOLAR-WIND AB Ground magnetic field perturbations recorded by the CANOPUS magnetometer network in the 7 to 13 MLT sector are used to examine how reconfigurations of the dayside polar ionospheric flow take place in response to north-south changes of the IMF. During the 6-hour interval in question IMF B(z) oscillates between +/-7 nT with about a 1-hour period. Corresponding variations in the ground magnetic disturbance are observed which we infer are due to changes in ionospheric flow. Cross correlation of the data obtained from two ground stations at 73.5-degrees magnetic latitude, but separated by approximately 2 hours in MLT, shows that changes in the flow are initiated in the prenoon sector (approximately 10 MLT) and then spread outward toward dawn and dusk with a phase speed of approximately 5 km s-1 over the longitude range approximately 8 to 12 MLT, slowing to approximately 2 km s-1 outside this range. Cross correlating the data from these ground stations with IMP 8 IMF B(z) records produces a MLT variation in the ground response delay relative to the IMF which is compatible with these deduced phase speeds. We interpret these observations in terms of the ionospheric response to the onset, expansion and decay of magnetic reconnection at the dayside magnetopause. C1 NASA,GODDARD SPACE FLIGHT CTR,CODE 692,GREENBELT,MD 20771. NATL RES COUNCIL CANADA,HERZBERG INST ASTROPHYS,OTTAWA K1A 0R6,ONTARIO,CANADA. UNIV ALBERTA,DEPT PHYS,CANADIAN NETWORK SPACE RES,EDMONTON T6G 2J1,ALBERTA,CANADA. NATL RES COUNCIL CANADA,HERZBERG INST ASTROPHYS,OTTAWA K1A 0R6,ONTARIO,CANADA. RP SAUNDERS, MA (reprint author), UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED,BLACKETT LAB,LONDON SW7 2BZ,ENGLAND. RI Lockwood, Mike/G-1030-2011 OI Lockwood, Mike/0000-0002-7397-2172 NR 61 TC 59 Z9 59 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19373 EP 19380 DI 10.1029/92JA01383 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800024 ER PT J AU BENSON, RF OSHEROVICH, VA AF BENSON, RF OSHEROVICH, VA TI HIGH-ORDER STIMULATED IONOSPHERIC DIFFUSE PLASMA RESONANCES - SIGNIFICANCE FOR MAGNETOSPHERIC EMISSIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FREE ELECTROMAGNETIC-FIELDS; CYLINDRICAL OSCILLATIONS; PHYSICAL NATURE; TURBULENCE; FREQUENCY; SEQUENCE; PULSES; WAVES AB The sequence nature of the diffuse ionospheric resonances D(n) stimulated by topside sounders was discovered by Oya (1970) with n ranging from 1 to 4. Osherovich (1987) organized these observations using his earlier theory which predicted a nonequidistant spectrum with frequencies proportional to n 1/2-where n = 1, 2, . . . . This work has since been used to predict the exact spectral position of naturally occurring magnetospheric emissions, and such emissions corresponding to n = 4 and 5 were identified in the IMP 6 data. These results motivated a search for the stimulated ionospheric counterpart at n = 5. We here present Alouette 2 and ISIS 1 topside sounder evidence for the stimulation of D(n) resonances with n > 4. The results indicate the close relationship between active ionospheric plasma wave experiments and the interpretation of magnetospheric emissions. C1 HUGHES STX CORP,LANHAM,MD. RP BENSON, RF (reprint author), NASA,GODDARD SPACE FLIGHT CTR,EXTRATERR PHYS LAB,INTERPLANETARY PHYS BRANCH,CODE 692,GREENBELT,MD 20771, USA. NR 27 TC 15 Z9 15 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19413 EP 19419 DI 10.1029/92JA01524 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800028 ER PT J AU BROADFOOT, AL ANDERSON, E SHERARD, P KNECHT, DJ VIERECK, RA PIKE, CP MURAD, E ELGIN, JE BERNSTEIN, LS KOFSKY, IL RALL, DLA BLAHA, J CULBERTSON, FL AF BROADFOOT, AL ANDERSON, E SHERARD, P KNECHT, DJ VIERECK, RA PIKE, CP MURAD, E ELGIN, JE BERNSTEIN, LS KOFSKY, IL RALL, DLA BLAHA, J CULBERTSON, FL TI SPECTROGRAPHIC OBSERVATION AT WAVELENGTHS NEAR 630 NM OF THE INTERACTION BETWEEN THE ATMOSPHERE AND THE SPACE-SHUTTLE EXHAUST SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ENVIRONMENT; ORBITER; H2O AB The collision between the exhaust from the Primary Reaction Control System (PRCS) engines (870 pounds thrust) of the space shuttle and the ambient atmosphere has been observed from the Air Force Maui Optical Station (AMOS). Spectra have been obtained in the wavelength region near 630 nm, The temporal, spatial, and spectral distribution of the emission in this region has been recorded. The results reported here indicate that when the exhaust of the space shuttle interacts with the atmosphere in the ram direction, an intense, long-lasting emission at 630 nm due to O(1D --> 3P) is generated. A substantial amount of O(1D) is swept back onto the orbiter. Two processes are proposed for the formation of O(1D): (1) excitation of atmospheric O(3P) by collisions with the exhaust of the space shuttle engines; and (2) charge exchange between ambient O+ and exhaust H2O. Calculations using the SOCRATES code show excellent agreement with the data. C1 OLAA WSSI,PHILLIPS LAB,BEDFORD,MA 01731. SPECTRAL SCI INC,BURLINGTON,MA 01803. NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. PHOTOMETR,WOBURN,MA 01801. RP BROADFOOT, AL (reprint author), UNIV ARIZONA,LUNAR & PLANETARY LAB,TUCSON,AZ 85721, USA. NR 22 TC 15 Z9 15 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1992 VL 97 IS A12 BP 19501 EP 19508 DI 10.1029/92JA01654 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD128 UT WOS:A1992KD12800035 ER PT J AU JAMSHIDI, M OH, BJ SERAJI, H AF JAMSHIDI, M OH, BJ SERAJI, H TI 2 ADAPTIVE-CONTROL STRUCTURES OF ROBOT MANIPULATORS SO JOURNAL OF INTELLIGENT & ROBOTIC SYSTEMS LA English DT Article DE ADAPTIVE CONTROL; DECENTRALIZED ADAPTIVE CONTROL; ROBOT MANIPULATOR; FEEDFORWARD CONTROL ID SYSTEMS AB This paper proposes two simple adaptive control schemes of robot manipulators. The first one is the state feedback control which consists of feedforward from the desired position trajectory, PD feedback from the actual trajectory, and an auxiliary input. The second one is the feedforward/feedback control which consists of a feedforward term from the desired position, velocity, and acceleration trajectory based on the inverse of robot dynamics. The feedforward, feedback, and auxiliary gains are adapted using simple equations derived from the decentralized adaptive control theory based on Lyapunov's direct method, and using only the local information of the corresponding joint. The proposed control schemes are computationally fast and do not require a priori knowledge of the detail parameters of the manipulator or the payload. Simulation results are presented in support of the proposed schemes. The results demonstrate that both controllers perform well with bounded adaptive gains. C1 KOREA ELECTR & TELECOMMUN RES INST,DEPT AUTOMAT TECHNOL,TAEJON,SOUTH KOREA. JET PROP LAB,PASADENA,CA 91109. RP JAMSHIDI, M (reprint author), UNIV NEW MEXICO,DEPT ELECT & COMP ENGN,CAD,INTELLIGENT & ROBOT SYST LAB,ALBUQUERQUE,NM 87131, USA. NR 9 TC 1 Z9 2 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0921-0296 J9 J INTELL ROBOT SYST JI J. Intell. Robot. Syst. PD DEC PY 1992 VL 6 IS 2-3 BP 203 EP 218 PG 16 WC Computer Science, Artificial Intelligence; Robotics SC Computer Science; Robotics GA KG233 UT WOS:A1992KG23300005 ER PT J AU LONG, MK AF LONG, MK TI TASK-DIRECTED INVERSE KINEMATICS FOR REDUNDANT MANIPULATORS SO JOURNAL OF INTELLIGENT & ROBOTIC SYSTEMS LA English DT Article DE REDUNDANT MANIPULATORS; KINEMATICS; INVERSE KINEMATICS; ALGORITHMS; REDUNDANCY RESOLUTION ID CONFIGURATION CONTROL; ROBOTS AB This paper presents kinematic algorithms for resolved-rate based inverse kinematics of redundant manipulators. Efficient and robust Jacobian and weighted damped least squares algorithms are given which provide a method that allows full utilization of the redundancy to best achieve task requirements. A nominal set of task space variables is suggested and procedures for modifying this specification or their relative priorities due to changing task requirements or events are discussed. Examples are shown using a simulation of the seven degree-of-freeom Robotics Research manipulator. These simulations demonstrate the singularity robustness of the algorithms and the ability to smoothly transition between task parameterizations and relative priorities. RP LONG, MK (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 27 TC 3 Z9 3 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0921-0296 J9 J INTELL ROBOT SYST JI J. Intell. Robot. Syst. PD DEC PY 1992 VL 6 IS 2-3 BP 241 EP 261 PG 21 WC Computer Science, Artificial Intelligence; Robotics SC Computer Science; Robotics GA KG233 UT WOS:A1992KG23300007 ER PT J AU RAJ, SV HEBSUR, M LOCCI, IE DOYCHAK, J AF RAJ, SV HEBSUR, M LOCCI, IE DOYCHAK, J TI EFFECT OF OXIDATION ON THE MECHANICAL-PROPERTIES OF A NBAL3 ALLOY AT INTERMEDIATE TEMPERATURES SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB Although a NbAl3 alloy containing Cr, W, and Y has excellent oxidation resistance above 1440 K, it suffers from severe environmental attack during deformation at intermediate temperatures between 900 and 1100 K. Specimens tested in constant velocity and constant load direct compression tests showed varying degrees of degradation depending on environment (i.e., air or argon), surface finish, stress, and temperature. As a result, there were corresponding differences in mechanical behavior and in the observed microstructures. At high stresses and strain rates, specimens with as-machined surfaces were brittle at and below 1100 K when tested in air but showed fracture strains above 4% when deformed in argon. However, reproducible compressive ductility of 2-3% was attained on polished specimens tested in air. At intermediate stresses, the creep curves showed sudden and periodic increases in strain before the specimens failed catastrophically after about 80 h. Microstructural examination of these specimens revealed extensive oxidation within cracks. Constant load tests conducted at lower stresses below 100 MPa showed an apparent incubation period where the change in the length of the specimen was immeasurably small. Following the incubation period, which typically lasted between 10 and 110 h depending on stress, temperature, and surface condition, specimens increased significantly in length due to oxide growth. In this case, considerable oxide spalling occurred during the course of the test, often leading to a substantial decrease in the cross-sectional area of the specimen. Microstructural observations revealed extensive cracking in the oxide layer and in the matrix, where the cracks had originated at the oxide-metal interface. The effects of environment on the mechanical properties are rationalized with the help of a schematic environmental-deformation mechanism map. C1 SVERDRUP TECHNOL INC,LERC GRP,CLEVELAND,OH 44135. RP RAJ, SV (reprint author), NASA,LEWIS RES CTR,MS 49-1,21000 BROOKPARK RD,CLEVELAND,OH 44135, USA. NR 23 TC 10 Z9 10 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD DEC PY 1992 VL 7 IS 12 BP 3219 EP 3234 DI 10.1557/JMR.1992.3219 PG 16 WC Materials Science, Multidisciplinary SC Materials Science GA KB464 UT WOS:A1992KB46400007 ER PT J AU RINSLAND, CP SMITH, MAH DEVI, VM BENNER, DC AF RINSLAND, CP SMITH, MAH DEVI, VM BENNER, DC TI MEASUREMENTS OF LORENTZ-BROADENING COEFFICIENTS AND PRESSURE-INDUCED LINE-SHIFT COEFFICIENTS IN THE NU-1-BAND OF HD O-16 AND THE NU-3-BAND OF D2 O-16 SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Note ID NU-2 BANDS; ATMOSPHERIC GASES; WATER-VAPOR; AIR; NITROGEN; SPECTRA; REGION C1 COLL WILLIAM & MARY,DEPT PHYS,WILLIAMSBURG,VA 23187. RP RINSLAND, CP (reprint author), NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,HAMPTON,VA 23665, USA. NR 20 TC 14 Z9 14 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD DEC PY 1992 VL 156 IS 2 BP 507 EP 511 DI 10.1016/0022-2852(92)90251-I PG 5 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA JY986 UT WOS:A1992JY98600022 ER PT J AU GOLUB, MA WYDEVEN, T CORMIA, RD AF GOLUB, MA WYDEVEN, T CORMIA, RD TI PLASMA COPOLYMERIZATION OF ETHYLENE AND TETRAFLUOROETHYLENE SO JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY LA English DT Article DE PLASMA COPOLYMERIZATION; ETHYLENE; TETRAFLUOROETHYLENE; INFRARED SPECTROSCOPY; X-RAY PHOTOELECTRON SPECTROSCOPY; COPOLYMER DEPOSITION RATES; MECHANISM ID ATOMIC OXYGEN; ESCA AB The plasma copolymerization of ethylene (ET) and tetrafluoroethylene (TFE) was investigated by means of IR and XPS analyses. The deposition rates for plasma ET/TFE copolymers, when plotted versus mol % TFE in the feed gas, gave a concave-downward curve situated above the straight-line joining the deposition rates for the respective plasma polymers, PPET and PPTFE, with the maximum rate at almost-equal-to 70-80 mol % TFE. This result, coupled with the finding that normalized absorbances of the C - H and C - F IR bands of ET/TFE copolymers had maxima at almost-equal-to 20 and 80 mol % TFE, respectively, indicated a positive interaction between ET and TFE such that each monomer "sensitized" the plasma copolymerization of the other. As analyzed by XPS, CF groups dominated over CF2 and CF3 groups at 5-70 mol % TFE, but at greater-than-or-equal-to 80 mol % TFE, these moieties approached the relative proportions in PPTFE (CF2 > CF3 > CF). The plot of F/C ratio versus mol % TFE was concave-upward and situated below the hypothetical straight-line plot representing noninteracting, independent polymerization of ET and TFE, while the % F in the plasma copolymers was linear with mol % TFE. The F1s mean binding energies of the ET/TFE plasma copolymers, which increased monotonically with % F, were consistently higher than those for several commercial polymers of fluorinated olefins at comparable values of % F. This result suggested clustering of CF(n) moieties in the plasma copolymers or the presence of F atoms in highly fluorinated environments. C1 SURFACE SCI LABS,MT VIEW,CA 94043. RP GOLUB, MA (reprint author), NASA,AMES RES CTR,MOFFETT FIELD,CA 94035, USA. NR 20 TC 26 Z9 26 U1 0 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0887-624X J9 J POLYM SCI POL CHEM JI J. Polym. Sci. Pol. Chem. PD DEC PY 1992 VL 30 IS 13 BP 2683 EP 2692 DI 10.1002/pola.1992.080301303 PG 10 WC Polymer Science SC Polymer Science GA JX757 UT WOS:A1992JX75700003 ER PT J AU ANGEL, PW HANN, RE AF ANGEL, PW HANN, RE TI GLASS-FORMATION, PROPERTIES AND STRUCTURE OF SODA YTTRIA SILICA GLASSES SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SYSTEM AB The glass-formation region of the soda-yttria-silica system was determined. The glasses within this region were measured to have a density of 2.4 to 3.1 g/cm3, a refractive index of 1.50 to 1.60, Vickers hardness values of 3.7 to 5.8 GPa, softening temperatures between 500-degrees and 780-degrees-C, and a coefficient of thermal expansion of 7 x 10(-6)/degrees-C to 19 x 10(-6)/degrees-C. Aqueous chemical durability measurements were made on select glass compositions while infrared transmission spectra were used to investigate the glass structure and its effect on glass properties. A compositional region was identified which exhibited high thermal expansion, high softening temperatures, and good chemical durability. RP ANGEL, PW (reprint author), NASA,LEWIS RES CTR,CLEVELAND,OH 44135, USA. NR 10 TC 6 Z9 6 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1992 VL 75 IS 12 BP 3278 EP 3282 DI 10.1111/j.1151-2916.1992.tb04421.x PG 5 WC Materials Science, Ceramics SC Materials Science GA KC291 UT WOS:A1992KC29100011 ER PT J AU CHEONG, DS SANDERS, WA AF CHEONG, DS SANDERS, WA TI HIGH-TEMPERATURE DEFORMATION AND MICROSTRUCTURAL ANALYSIS FOR SILICON-NITRIDE SCANDIUM (III) OXIDE SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID HOT-PRESSED SI3N4; RARE-EARTH-OXIDE; PHASE; STRENGTH AB Limited past studies have indicated that Si3N4 doped with Sc2O3 may exhibit high-temperature mechanical properties superior to Si3N4 systems with various other oxide sintering additives. High-temperature deformation of this system was studied by characterizing the microstructures before and after deformation. It was found that elements of the additive, Sc and O, exist in small amounts at thin grain boundary layers and within secondary phases at triple and multiple grain boundary junctions. The secondary phase is devitrified as crystalline Sc2Si2O7. Deformation of the samples was dominated by cavitation rather than dislocation processes. Thus, the excellent deformation resistance of the samples at high temperature can be attributed to the high refractories and enhanced crystallization of a secondary phase. C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. RP CHEONG, DS (reprint author), KOREA ADV INST SCI & TECHNOL,SEOUL 131,SOUTH KOREA. NR 19 TC 22 Z9 22 U1 1 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1992 VL 75 IS 12 BP 3331 EP 3336 DI 10.1111/j.1151-2916.1992.tb04429.x PG 6 WC Materials Science, Ceramics SC Materials Science GA KC291 UT WOS:A1992KC29100019 ER PT J AU THRALL, KD SAUER, RL BULL, RJ AF THRALL, KD SAUER, RL BULL, RJ TI EVIDENCE OF THYROXINE FORMATION FOLLOWING IODINE ADMINISTRATION IN SPRAGUE-DAWLEY RATS SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH LA English DT Article AB Iodine (I2) has been proposed to be used as a water disinfectant on the manned space station. Previous work has shown that subchronic administration of I2 to Sprague-Dawley rats in drinking water significantly increases plasma thyroxine/triiodothyronine (T4/T3) levels. This is not observed with iodide (I-) treatment. The present study addresses the possibility that I2 reacts with deiodinated T4 metabolites in the gastrointestinal tract to resynthesize T4. Incubation of diiodothyronine (T2), T3, or reverse T3 with I2 in phosphate-buffered saline resulted in the formation of T4 as measured by radioimmunoassay. Washes from the initial segments of the small intestine of the rat show that substrates are present that react with I2 to produce T4. Single oral doses of I2 to rats produced significant dose-related increases in serum T4 and decreases in T3 concentrations after 2 h. Administration of an equivalent dose of I- did not alter significantly plasma T4 concentrations. Higher concentrations of a radioactive substance that bound a T4-specific antibody are present in plasma of animals treated with I-125(2) compared to I-125-. These data support the hypothesis that I2 reacts with metabolites of thyroid hormone in the gastrointestinal tract to resynthesize T4 and elevate its levels in blood. C1 WASHINGTON STATE UNIV,COLL PHARM,PHARMACOL TOXICOL GRAD PROGRAM,PULLMAN,WA 99164. NASA,LYNDON B JOHNSON SPACE CTR,DIV SPACE & LIFE SCI,HOUSTON,TX 77058. RP THRALL, KD (reprint author), BATTELLE PNL,DEPT HLTH PHYS K354,POB 999,RICHARD,WA 99352, USA. NR 22 TC 9 Z9 9 U1 0 U2 0 PU TAYLOR & FRANCIS PI BRISTOL PA 1900 FROST ROAD, SUITE 101, BRISTOL, PA 19007-1598 SN 0098-4108 J9 J TOXICOL ENV HEALTH JI J. Toxicol. Environ. Health PD DEC PY 1992 VL 37 IS 4 BP 535 EP 548 PG 14 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA KD147 UT WOS:A1992KD14700006 PM 1464908 ER PT J AU DAVIS, MW OLLA, BL AF DAVIS, MW OLLA, BL TI COMPARISON OF GROWTH, BEHAVIOR AND LIPID CONCENTRATIONS OF WALLEYE POLLOCK THERAGRA-CHALCOGRAMMA LARVAE FED LIPID-ENRICHED, LIPID-DEFICIENT AND FIELD-COLLECTED PREY SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article ID FATTY-ACID COMPOSITION; FREE AMINO-ACIDS; ANCHOVY ENGRAULIS-MORDAX; COD GADUS-MORHUA; DEVELOPING EGGS; BASS LARVAE; FISH LARVAE; FOOD; SURVIVAL; ZOOPLANKTON AB While growth and survival of marine fish larvae in the sea may be dependent on prey type, size and concentration, nutritional quality of prey may also play an important role. This study investigates the relationships of lipid content of prey with growth, gas bladder size, sinking rate, behavior and survival for larval walleye pollock Theragra chalcogramma under controlled conditions in the laboratory. Larvae fed lipid-deficient brine shrimp Artemia spp. nauplii had reduced growth, gas bladder size and survival. These larvae also had to swim almost continuously to maintain vertical position in the water column. In contrast, larvae fed wild-caught copepods or Artemia spp. enriched with lipid showed alternating swimming and resting bouts. The potential for vagaries in meteorological and oceanographic conditions to cause larval fish prey to be nutrient deficient is discussed. RP DAVIS, MW (reprint author), NATL MARINE FISHERIES SERV, ALASKA FISHERIES SCI CTR, HATFIELD MARINE SCI CTR, NEWPORT, OR 97365 USA. NR 47 TC 39 Z9 40 U1 0 U2 6 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PD DEC PY 1992 VL 90 IS 1 BP 23 EP 30 DI 10.3354/meps090023 PG 8 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA KK401 UT WOS:A1992KK40100003 ER PT J AU MINELLO, TJ ZIMMERMAN, RJ AF MINELLO, TJ ZIMMERMAN, RJ TI UTILIZATION OF NATURAL AND TRANSPLANTED TEXAS SALT MARSHES BY FISH AND DECAPOD CRUSTACEANS SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article ID SHRIMP PENAEUS-AZTECUS; JUVENILE BLUE CRABS; FUNDULUS-HETEROCLITUS; BROWN SHRIMP; SPARTINA-ALTERNIFLORA; PALAEMONETES-PUGIO; NORTH-CAROLINA; GRASS SHRIMP; MICROHABITAT SELECTION; CALLINECTES-SAPIDUS AB Habitat utilization by fish and decapod crustaceans was compared among 3 transplanted and 3 natural Spartina alterniflora marshes on the Texas (USA) coast during spring 1986. Created marshes had been transplanted on dredged material and were approximately 2 to 5 yr old at the time of sampling. Although conclusions are limited to the spring season, the use of replicate marshes allowed us to test the null hypothesis that transplanted marshes on the Texas coast were equivalent to natural marshes. Mean values for stem density and above-ground biomass of S. alterniflora were consistently higher in the transplanted marshes, and the difference was statistically significant for stem density. Macro-organic matter (MOM) in the upper 5 cm of sediment was significantly lower in the transplanted marshes. Densities of polychaetes and amphipods within transplanted marshes were positively correlated with this MOM. Transplanted marshes had significantly lower densities of decapod crustacea (primarily daggerblade grass shrimp Palaemonetes pugio and juvenile brown shrimp Penaeus aztecus) compared with natural marshes. This reduced utilization may have been a response to low densities of benthic food organisms, and densities of decapods were positively correlated with densities of prey in sediment cores. In contrast to the utilization pattern of decapods, densities of fish (dominated by the darter goby Gobionellus boleosoma and pinfish Lagodon rhomboides) were similar between natural and transplanted marshes. These small fish may rely on salt marshes more for protective cover than for enhanced food resources, and above-ground structure in the transplanted marshes may have adequately provided this function. Comparisons of functional equivalency between natural and transplanted salt marshes require adequate information on how salt marshes actually function for fish and decapod crustaceans. For example, the use of prey density as an indicator of food value in a marsh can be misleading unless trophic pathways are well understood and access to the marsh surface is considered. RP MINELLO, TJ (reprint author), NOAA, NATL MARINE FISHERIES SERV, SE FISHERIES CTR, GALVESTON LAB, 4700 AVE U, GALVESTON, TX 77550 USA. NR 91 TC 75 Z9 76 U1 0 U2 15 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PD DEC PY 1992 VL 90 IS 3 BP 273 EP 285 DI 10.3354/meps090273 PG 13 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA KN492 UT WOS:A1992KN49200006 ER PT J AU LECKEMITCHELL, KM MULLIN, K AF LECKEMITCHELL, KM MULLIN, K TI DISTRIBUTION AND ABUNDANCE OF LARGE FLOATING PLASTIC IN THE NORTH-CENTRAL GULF OF MEXICO SO MARINE POLLUTION BULLETIN LA English DT Article AB Aerial surveys were conducted in the north-central Gulf of Mexico from June 1988 to May 1989. Sightings of marine debris and specifically large floating plastics were recorded during these surveys. Five study areas off the Louisiana coast were monitored and seasonal distribution and densities were estimated. Each study area contained plastic throughout the year. The estimated densities of plastic were largest in the offshore areas (4 & 5) and smallest in the inshore areas (1 & 3). Seasonally, density of plastic was smallest in the summer and largest in the fall. The reasons for the differences in seasons and study areas are not apparent but the amount of plastic in each area and season could be affected by variations in currents, winds, discharge from rivers, and human activity. RP NOAA, NATL MARINE FISHERIES SERV, SE FISHERIES SCI CTR, PO DRAWER 1207, PASCAGOULA, MS 39568 USA. NR 8 TC 21 Z9 21 U1 3 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-326X EI 1879-3363 J9 MAR POLLUT BULL JI Mar. Pollut. Bull. PD DEC PY 1992 VL 24 IS 12 BP 598 EP 601 DI 10.1016/0025-326X(92)90279-F PG 4 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA KF555 UT WOS:A1992KF55500005 ER PT J AU GRIEVE, RAF CINTALA, MJ AF GRIEVE, RAF CINTALA, MJ TI AN ANALYSIS OF DIFFERENTIAL IMPACT-MELT CRATER-SCALING AND IMPLICATIONS FOR THE TERRESTRIAL IMPACT RECORD SO METEORITICS LA English DT Review ID MISTASTIN-LAKE-CRATER; GEOMETRIC MODEL; CANADA; QUEBEC; ROCKS; SUDBURY; RIES; MECHANICS; PETROLOGY; CHEMISTRY AB It has been known for some time that the volume of impact melt (V(m)) relative to that of the transient cavity (V(tc)) increases with the magnitude of the impact event. This paper investigates the influence that this phenomenon has on the nature of terrestrial impact craters. A model of impact melting is used to estimate the volume of melt produced during the impact of chondritic projectiles into granite targets at velocities of 15, 25, and 50 km s-1. The dimensions of transient cavities formed under the same impact conditions are calculated from current crater-scaling relationships, which are derived from dimensional analysis of data from cratering experiments. Observed melt volumes at terrestrial craters are collated from the literature and are paired with the transient-cavity diameters (D(tc)) of their respective craters; these diameters were determined through an established empirical relationship. The model and observed melt volumes have very similar trends with increasing transient-cavity diameter. This V(m)-D(tc) relationship is then used to make predictions regarding the nature of the terrestrial cratering record. In particular, with increasing size of the impact event, the depth of melting approaches the depth of the transient cavity. As a consequence, the base of the cavity, which ultimately would appear as an uplifted central structure in a complex crater, will record shock stresses that will increase up to a maximum of partial melting. Examination of the terrestrial record indicates a general trend for higher recorded shock levels in central structures at larger diameters; impact structures in the 100-km size range record partially melted and vesiculated parautochthonous target rocks in their centers. In addition, as the depth of melting approaches a depth equivalent to that attained by the base of the transient cavity, the floor of the transient cavity will have progressively less strength, with the result that cavity modification and uplift will not produce topographic central peaks. Again, the observed terrestrial record is not inconsistent with this prediction, and we offer differential melt scaling as a possible mechanism for the transition from central topographic peaks to rings with increasing crater diameter. Among other implications is the likelihood that impact basins in the 1000-km size range on the early Earth would not have the same multi-ring form as observed on the moon. C1 NASA,LYNDON B JOHNSON SPACE CTR,PLANETARY SCI BRANCH,HOUSTON,TX 77058. RP GRIEVE, RAF (reprint author), GEOL SURVEY CANADA,DIV GEOPHYS,OTTAWA K1A 0Y3,ON,CANADA. NR 123 TC 168 Z9 173 U1 1 U2 13 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 SN 0026-1114 J9 METEORITICS JI Meteoritics PD DEC PY 1992 VL 27 IS 5 BP 526 EP 538 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KH005 UT WOS:A1992KH00500005 ER PT J AU NICHOLS, RH NUTH, JA HOHENBERG, CM OLINGER, CT MOORE, MH AF NICHOLS, RH NUTH, JA HOHENBERG, CM OLINGER, CT MOORE, MH TI TRAPPING OF NOBLE-GASES IN PROTON-IRRADIATED SILICATE SMOKES SO METEORITICS LA English DT Article ID FRACTIONATION; METEORITES; ARGON; NEON AB We have measured Ne, Ar, Kr and Xe in Si2O3 ''smokes'' that were condensed on Al substrates, vapor-deposited with various mixtures of CH4, NH3, H2O and noble gases at 10 K and subsequently irradiated with 1 MeV protons to simulate conditions during grain mantle formation in interstellar clouds. The noble gases were analyzed using conventional stepwise heating and static noble gas mass spectrometry. Neither Ne nor Ar is retained by the samples upon warming to room temperature, but Xe is very efficiently trapped and retained. Kr is somewhat less effectively retained, typically depleted by factors of about 10-20 relative to Xe. Isotopic fractionation favoring the heavy isotopes of Xe and Kr of about 5-10 parts per thousand/amu is observed. Correlations between the specific chemistry of the vapor deposition and heavy noble gas retention are most likely the result of competition by the various species for irradiation-produced trapping sites. The concentration of Xe retained by some of these smokes exceeds that observed in phase Q of meteorites and, like phase Q, they do not seem to be carriers of the light noble gases. Such artificially prepared material may, therefore, offer clues concerning the incorporation of the heavy planetary noble gases in meteoritic material and the nature of phase Q. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP NICHOLS, RH (reprint author), WASHINGTON UNIV,MCDONNELL CTR SPACE SCI,ST LOUIS,MO 63130, USA. RI Nuth, Joseph/E-7085-2012 NR 17 TC 8 Z9 8 U1 0 U2 2 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 SN 0026-1114 J9 METEORITICS JI Meteoritics PD DEC PY 1992 VL 27 IS 5 BP 555 EP 559 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KH005 UT WOS:A1992KH00500007 ER PT J AU ZOLENSKY, ME HEWINS, RH MITTLEFEHLDT, DW LINDSTROM, MM XIAO, X LIPSCHUTZ, ME AF ZOLENSKY, ME HEWINS, RH MITTLEFEHLDT, DW LINDSTROM, MM XIAO, X LIPSCHUTZ, ME TI MINERALOGY, PETROLOGY AND GEOCHEMISTRY OF CARBONACEOUS CHONDRITIC CLASTS IN THE LEW-85300 POLYMICT EUCRITE SO METEORITICS LA English DT Article ID COMPOSITIONAL CLASSIFICATION; BHOLGHATI HOWARDITE; CHEMICAL FRACTIONATIONS; AQUEOUS ALTERATION; TRACE-ELEMENTS; METEORITES; ABUNDANCES; MATRIX; PARENT AB We have performed a detailed petrologic and mineralogic study of two chondritic clasts from the polymict eucrite Lewis Cliff (LEW) 85300, and performed chemical analyses by INAA and RNAA on one of these. Petrologically, the clasts are identical and are composed of dispersed aggregates, chondrules and chondrule fragments supported by matrix. The aggregates and chondrules are composed of olivine (Fo100-45), orthopyroxene (Wo1-2En98-60), plus some diopside. The matrix consists of fine-grained olivine (Fo66-53), and lesser orthopyroxene and augite. Fine-grained saponite is common in the matrix. The bulk major element composition of the matrix is identical in both clasts and similar to that of CM, CO and CV chondrites. The bulk composition of the clast studied by INAA and RNAA shows unusual abundance patterns for lithophile, siderophile and chalcophile elements but is basically chondritic. The INAA/RNAA data preclude assignment of the LEW 85300,15 clast to any commonly accepted group of carbonaceous chondrite. The unusual rare earth element abundance pattern may, in part, be due to terrestrial alteration. C1 LOCKHEED ENGN & SCI CO,HOUSTON,TX 77058. RUTGERS STATE UNIV,DEPT GEOL SCI,NEW BRUNSWICK,NJ 08903. PURDUE UNIV,DEPT CHEM,W LAFAYETTE,IN 47907. RP ZOLENSKY, ME (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,DIV SOLAR SYST EXPLORAT SN2,HOUSTON,TX 77058, USA. NR 41 TC 25 Z9 25 U1 0 U2 6 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 SN 0026-1114 J9 METEORITICS JI Meteoritics PD DEC PY 1992 VL 27 IS 5 BP 596 EP 604 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KH005 UT WOS:A1992KH00500013 ER PT J AU STARR, DO KORB, CL SCHWEMMER, GK WENG, CY AF STARR, DO KORB, CL SCHWEMMER, GK WENG, CY TI OBSERVATIONS OF HEIGHT-DEPENDENT PRESSURE-PERTURBATION STRUCTURE OF A STRONG MESOSCALE GRAVITY-WAVE SO MONTHLY WEATHER REVIEW LA English DT Article ID ATMOSPHERIC-PRESSURE; LIDAR MEASUREMENTS; SOURCE MECHANISMS; MORNING GLORY; DOPPLER RADAR; SHEAR LAYERS; RAMAN LIDAR; THUNDERSTORMS; DISTURBANCES; PROFILE AB Airborne observations using a downward-looking, dual-frequency, near-infrared, differential absorption lidar (DIAL) system provide the first measurements of the height-dependent pressure-perturbation field associated with a strong mesoscale gravity wave. A pressure-perturbation amplitude of 3.5 mb was measured within the lowest 1.6 km of the atmosphere over a 52-km flight line. Corresponding vertical displacements of 250-500 m were inferred from lidar-observed displacement of aerosol layers. Accounting for probable wave orientation, a horizontal wavelength of about 40 km was estimated. Satellite observations reveal wave structure of a comparable scale in concurrent cirrus cloud fields over an extended area. Smaller-scale waves were also observed. Local meteorological soundings are analyzed to confirm the existence of a suitable wave duct. Potential wave-generation mechanisms are examined and discussed. The large pressure-perturbation wave is attributed to rapid amplification or possible wave breaking of a gravity wave as it propagated offshore and interacted with a very stable marine boundary layer capped by a strong shear layer. C1 SCI SYST & APPLICAT INC,SEABROOK,MD. RP STARR, DO (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ATMOSPHERES LAB,GREENBELT,MD 20771, USA. NR 45 TC 4 Z9 4 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD DEC PY 1992 VL 120 IS 12 BP 2808 EP 2820 DI 10.1175/1520-0493(1992)120<2808:OOHDPP>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KD045 UT WOS:A1992KD04500007 ER PT J AU BLADOS, WR COTTER, GA AF BLADOS, WR COTTER, GA TI AN INTERNATIONAL AEROSPACE INFORMATION-SYSTEM - A COOPERATIVE OPPORTUNITY SO ONLINE REVIEW LA English DT Article AB Scientific and technical information (STI) is a valuable resource that represents the results of large investments in research and development (R&D) and the expertise of a nation. NASA and its predecessor organizations have developed and managed the pre-eminent aerospace information system. We see information and information systems changing and becoming more international in scope. In Europe, consistent with joint R&D programs and a view towards a united Europe, we have seen the emergence of a European Database concept. In addition, the development of aeronautics and astronautics in individual nations has also led to initiatives for national aerospace databases. Considering recent technological developments in information science and technology, as well as the reality of scarce resources in all nations, it is time to reconsider the mutually beneficial possibilities offered by cooperation and international resource sharing. This paper raises for consideration new possibilities for unifying the various aerospace database efforts towards a cooperative international aerospace database initiative that can optimize the cost/benefit equation for all participants. RP BLADOS, WR (reprint author), NASA,SCI & TECH INFORMAT PROGRAM,INT BRANCH,CODE JTT,WASHINGTON,DC 20546, USA. NR 8 TC 1 Z9 1 U1 2 U2 2 PU LEARNED INFORMATION LTD PI OXFORD PA WOODSIDE, HINKSEY HILL, OXFORD, ENGLAND OX1 5AU SN 0309-314X J9 ONLINE REV PD DEC PY 1992 VL 16 IS 6 BP 359 EP 368 DI 10.1108/eb024411 PG 10 WC Computer Science, Information Systems; Information Science & Library Science SC Computer Science; Information Science & Library Science GA KE007 UT WOS:A1992KE00700001 ER PT J AU LAPOINTE, MR AF LAPOINTE, MR TI REVIEW OF NONDIFFRACTING BESSEL BEAM EXPERIMENTS SO OPTICS AND LASER TECHNOLOGY LA English DT Article DE BESSEL BEAMS; NONDIFFRACTING BEAMS; OPTICAL SYSTEMS ID NONDIFFRACTING BEAMS; WAVE-EQUATION AB The theory of non-diffracting Bessel beam propagation and the experimental evidence for nearly-non-diffracting Bessel beam propagation are reviewed. The experimental results are analysed to show that the observed propagation distances are characteristic of the optical systems used to transport the beams, and are not unique to the Bessel beam intensity profiles. The results indicate that, despite the innovative techniques employed to generate finite radius Bessel beam distributions, nearly-non-diffracting Bessel beam propagation has not yet been conclusively demonstrated. RP LAPOINTE, MR (reprint author), SVERDRUP TECHNOL INC,NASA,LERC GRP,2001 AEROSP PKWY,BROOK PK,OH 44142, USA. NR 16 TC 58 Z9 58 U1 3 U2 16 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0030-3992 J9 OPT LASER TECHNOL JI Opt. Laser Technol. PD DEC PY 1992 VL 24 IS 6 BP 315 EP 321 DI 10.1016/0030-3992(92)90082-D PG 7 WC Optics; Physics, Applied SC Optics; Physics GA KC532 UT WOS:A1992KC53200001 ER PT J AU ZHOU, SM CAMPBELL, S YEH, PC LIU, HK AF ZHOU, SM CAMPBELL, S YEH, PC LIU, HK TI MODIFIED-SIGNED-DIGIT OPTICAL COMPUTING BY USING FAN-OUT ELEMENTS SO OPTICS LETTERS LA English DT Article ID SYMBOLIC SUBSTITUTION AB We present a novel three-step modified-signed-digit optical computing system based on the discrete correlation of space-coded input matrices that are multiply imaged by using optical fan-out elements. The advantages of our method over other approaches include a larger throughput, more flexible operation, and an easier optical implementation. C1 JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109. RP ZHOU, SM (reprint author), UNIV CALIF SANTA BARBARA,DEPT ELECT & COMP ENGN,SANTA BARBARA,CA 93106, USA. RI Yeh, Pochi/A-2109-2010 NR 14 TC 15 Z9 16 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD DEC 1 PY 1992 VL 17 IS 23 BP 1697 EP 1699 DI 10.1364/OL.17.001697 PG 3 WC Optics SC Optics GA JZ935 UT WOS:A1992JZ93500018 PM 19798288 ER PT J AU Brock, JC McClain, CR Anderson, DM Prell, WL Hay, WW AF Brock, John C. McClain, Charles R. Anderson, David M. Prell, Warren L. Hay, William W. TI SOUTHWEST MONSOON CIRCULATION AND ENVIRONMENTS OF RECENT PLANKTONIC FORAMINIFERA IN THE NORTHWESTERN ARABIAN SEA SO PALEOCEANOGRAPHY LA English DT Article AB Digital hydrographic data combined with satellite thermal infrared and visible band remote sensing provide a synoptic climatological view of the shallow planktonic environment. This paper uses wind, hydrographic, and ocean remote sensing data to examine southwest monsoon controls on the foraminiferal faunal composition of Recent seafloor sediments of the northwestern Arabian Sea. Ekman pumping resulting in open-ocean upwelling and coastal upwelling create two distinctly different mixed layer plankton environments in the northwestern Arabian Sea during the summer monsoon. Open-sea upwelling to the northwest of the mean July position of the Findlater Jet axis yields a mixed layer environment with temperatures of less than 25 degrees C to about 26.5 degrees C, phytoplankton pigment concentrations between 1.5 and 5.0 mg/m3, and mixed layer depths less than 50 m. Convergence in the Ekman layer in the central Arabian Sea drives the formation of a mixed layer that is greater than 50 m thick, warmer than about 26.5 degrees C, and has phytoplankton pigment concentrations generally below 2.0 mg/m3. Coastal upwelling creates an extremely eutrophic plankton environment that persists over and immediately adjacent to the Omani shelf and undergoes significant offshore transport only within topographically induced coastal squirts. The foraminiferal faunal composition of upper Pleistocene deep-sea sediments of the northwestern Arabian Sea are mainly controlled by vertical nutrient fluxes caused by Ekman pumping, not coastal upwelling. Transfer functions for late Pleistocene mixed layer depth, temperature, and chlorophyll have been obtained through factor analysis and nonlinear multiple regression between late summer mixed layer environment and Recent sediment faunal observations. C1 [Brock, John C.; Hay, William W.] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. [McClain, Charles R.] NASA, Goddard Space Flight Ctr, Oceans & Ice Branch, Greenbelt, MD 20771 USA. [Anderson, David M.] NOAA, Paleoclimatol Program, Boulder, CO 80303 USA. [Prell, Warren L.] Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. RP Brock, JC (reprint author), Fisheries & Oceans Canada, Bedford Inst Oceanog, Div Biol Oceanog, Dartmouth, NS B2Y 4A2, Canada. FU NASA; NASA RTOPS [161-30-02, 161-30-21, 161-80-51]; American Chemical Society FX This research was conducted within the Oceans and Ice Branch at NASA Goddard Space Flight Center. J. Brock gratefully acknowledges support from the NASA Graduate Researcher Assistantship Program. Funding for C. McClain was provided by NASA RTOPS 161-30-02, 161-30-21, and 161-80-51. We acknowledge the support of the donors of the Petroleum Research Fund administered by the American Chemical Society. The authors thank J. Ryan, and J. Firestone, E. Yeh and M. Darzi of General Sciences Corporation for assistance in processing the satellite, wind, and hydrographic data sets. The FSU wind fields were provided by D. Legler and J. O'Brien. The authors also wish to express their gratitude to the reviewers, L. Sautter, R. Kroon, and W. Curry, whose constructive criticism significantly improved the manuscript. NR 43 TC 60 Z9 62 U1 2 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0883-8305 J9 PALEOCEANOGRAPHY JI Paleoceanography PD DEC PY 1992 VL 7 IS 6 BP 799 EP 813 DI 10.1029/92PA01267 PG 15 WC Geosciences, Multidisciplinary; Oceanography; Paleontology SC Geology; Oceanography; Paleontology GA V23KI UT WOS:000208341300007 ER PT J AU REID, MB HINE, BP AF REID, MB HINE, BP TI TERRAIN TRACKING FOR LANDER GUIDANCE USING BINARY PHASE-ONLY SPATIAL FILTERS SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article AB We demonstrate the use of binary phase-only spatial filters (BPOFs) for tracking target sites through a sequence of gray-scale terrain images. The filters are demonstrated in a closed loop guidance system for a laboratory lander mockup. Images of a 3D terrain board taken by the lander's video camera are preprocessed to produce binary intensity contour maps of a simulated planetary surface. A BPOF is made from a section of the current preprocessed image centered on the exact desired landing site. After the lander has descended to a lower altitude, the BPOF is correlated with a new image. The position of the correlation peak is used in making the next filter and to guide the lander so as to recenter the landing site in the camera's view. We present testbed results of the accuracy with which a site may be tracked from orbit to landing, and the maximum scale, translation, and rotation which can be tolerated between subsequent images. Application of the results to NASA's proposed Mars Rover Sample Return (MRSR) and Mars Environmental Survey (MESUR) missions is discussed. RP REID, MB (reprint author), NASA,AMES RES CTR,COMPUTAT SYST RES BRANCH,MAIL STOP 269-3,MOFFETT FIELD,CA 94035, USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD DEC PY 1992 VL 58 IS 12 BP 1699 EP 1706 PG 8 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA KB077 UT WOS:A1992KB07700008 ER PT J AU SARKAR, S AF SARKAR, S TI THE PRESSURE DILATION CORRELATION IN COMPRESSIBLE FLOWS SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article ID TURBULENCE AB Simulations of simple compressible flows have been performed to enable the direct estimation of the pressure-dilatation correlation. The generally accepted belief that this correlation may be important in high-speed flows has been verified by the simulations. The pressure-dilatation correlation is theoretically investigated by considering the equation for fluctuating pressure in an arbitrary compressible flow. This leads to the isolation of a component of the pressure-dilatation that exhibits temporal oscillations on a fast time scale. Direct numerical simulations of homogeneous shear turbulence and isotropic turbulence show that this fast component has a negligible contribution to the evolution of turbulent kinetic energy. Then, an analysis for the case of homogeneous turbulence is performed to obtain a formal solution for the nonoscillatory pressure-dilatation. Simplifications lead to a model that algebraically relates the pressure-dilatation to quantities traditionally obtained in incompressible turbulence closures. The model is validated by direct comparison with the simulations. RP NASA, LANGLEY RES CTR, INST COMP APPLICAT SCI & ENGN, HAMPTON, VA 23665 USA. NR 16 TC 95 Z9 104 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD DEC PY 1992 VL 4 IS 12 BP 2674 EP 2682 DI 10.1063/1.858454 PG 9 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KA357 UT WOS:A1992KA35700010 ER PT J AU LIOU, WW MORRIS, PJ AF LIOU, WW MORRIS, PJ TI WEAKLY NONLINEAR MODELS FOR TURBULENT MIXING IN A PLANE MIXING LAYER SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article ID LARGE-SCALE STRUCTURES; FREE SHEAR LAYERS; INSTABILITY WAVES; REYNOLDS-NUMBER; FLOWS; JETS; REGION; SOUND; WAKE AB New closure models for turbulent free shear flows are presented in this paper. They are based on a weakly nonlinear theory with a description of the dominant large-scale structures as instability waves. Two models are presented that describe the evolution of the free shear flows in terms of the time-averaged mean flow and the dominant large-scale turbulent structure. The local characteristics of the large-scale motions are described using linear theory. Their amplitude is determined from an energy integral analysis. The models have been applied to the study of an incompressible mixing layer. For both models, predictions of the mean flow development are made. In the second model, predictions of the time-dependent motion of the large-scale structures in the mixing layer are made. The predictions show good agreement with experimental observations. C1 PENN STATE UNIV,DEPT AEROSP ENGN,UNIV PK,PA 16801. RP LIOU, WW (reprint author), NASA,LEWIS RES CTR,ICOMP,CTR MODELING TURBULENCE & TRANSIT,CLEVELAND,OH 44135, USA. NR 34 TC 8 Z9 8 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD DEC PY 1992 VL 4 IS 12 BP 2798 EP 2808 DI 10.1063/1.858336 PG 11 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KA357 UT WOS:A1992KA35700020 ER PT J AU DEGANI, D TOBAK, M AF DEGANI, D TOBAK, M TI EXPERIMENTAL-STUDY OF CONTROLLED TIP DISTURBANCE EFFECT ON FLOW ASYMMETRY SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article ID VORTEX ASYMMETRY; REVOLUTION; BODY AB The effect on the asymmetric mean flow observed on pointed bodies of revolution at incidence of changing the size and location of a controlled disturbance as well as changes in angle of attack and flow conditions are evaluated experimentally. Flow visualization and side-force measurements are carried out for a generic ogive-cylinder body inclined at high angle of attack in a low-speed wind tunnel. For all angles of attack tested (30-degrees-60-degrees), minute changes in the size or location of the controlled disturbance result in finite changes in the asymmetric flow field, even to the extent of reversing the sign of the side force or becoming almost symmetric. The process is reversible; returning the wire to an original position likewise restores the corresponding flow field and mean side force. The variation of side force with continuous variation of a perturbation's size or location remains continuous and single valued, even in the incidence range of 50-degrees to 60-degrees, where "bistable" behavior of the asymmetric flow field is observed. C1 NASA,AMES RES CTR,DIV AERODYNAM,MOFFETT FIELD,CA 94035. RP DEGANI, D (reprint author), TECHNION ISRAEL INST TECHNOL,DEPT MECH ENGN,HAIFA,ISRAEL. NR 17 TC 25 Z9 26 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD DEC PY 1992 VL 4 IS 12 BP 2825 EP 2832 DI 10.1063/1.858338 PG 8 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KA357 UT WOS:A1992KA35700022 ER PT J AU SPEZIALE, CG GATSKI, TB SARKAR, S AF SPEZIALE, CG GATSKI, TB SARKAR, S TI ON TESTING MODELS FOR THE PRESSURE STRAIN CORRELATION OF TURBULENCE USING DIRECT SIMULATIONS SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article ID SHEAR FLOWS AB Direct simulations of homogeneous turbulence have, in recent years, come into widespread use for the evaluation of models for the pressure-strain correlation of turbulence. While work in this area has been beneficial, the increasingly common practice of testing the slow and rapid parts of these models separately in uniformly strained turbulent flows is shown in this paper to be unsound. For such flows, the decomposition of models for the total pressure-strain correlation into slow and rapid parts is ambiguous. Consequently, when tested in this manner, misleading conclusions can be drawn about the performance of pressure-strain models. This point is amplified by illustrative calculations of homogeneous shear flow where other pitfalls in the evaluation of models are also uncovered. More meaningful measures for testing the performance of pressure-strain models in uniformly strained turbulent flows are proposed and the implications for turbulence modeling are discussed. RP SPEZIALE, CG (reprint author), NASA,LANGLEY RES CTR,ICASE,HAMPTON,VA 23665, USA. NR 28 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD DEC PY 1992 VL 4 IS 12 BP 2887 EP 2899 DI 10.1063/1.858342 PG 13 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KA357 UT WOS:A1992KA35700027 ER PT J AU RONCHI, C YPMA, M CANUTO, VM AF RONCHI, C YPMA, M CANUTO, VM TI ON THE APPLICATION OF THE GERMANO IDENTITY TO SUBGRID-SCALE MODELING SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Note AB Germano [J. Fluid Mech. 238, 325 (1992)] has recently proposed an identity that has been widely applied to several turbulent flows to dynamically compute rather than adjust the Smagorinsky coefficient. In this Brief Communication, the assumptions under which the method has been used are discussed and some conceptual difficulties in its current implementation are pointed out. C1 COLUMBIA UNIV,DEPT APPL PHYS,NEW YORK,NY 10027. RP RONCHI, C (reprint author), NASA,GODDARD INST SPACE STUDIES,2880 BROADWAY,NEW YORK,NY 10025, USA. NR 6 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD DEC PY 1992 VL 4 IS 12 BP 2927 EP 2929 DI 10.1063/1.858346 PG 3 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA KA357 UT WOS:A1992KA35700032 ER PT J AU DAHLBURG, RB ANTIOCHOS, SK ZANG, TA AF DAHLBURG, RB ANTIOCHOS, SK ZANG, TA TI SECONDARY INSTABILITY IN 3-DIMENSIONAL MAGNETIC RECONNECTION SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID COHERENT NONLINEAR DESTABILIZATION; TANG VORTEX SYSTEM; TEARING MODE; COMPRESSIBLE MEDIUM; SHEET PINCH; FLOW; TURBULENCE; TRANSITION; EVOLUTION; COALESCENCE AB The transition to turbulence in three-dimensional reconnection of a magnetic neutral sheet is investigated. The transition can occur via a three-step process. First, the sheet undergoes the usual tearing instability. Second, the tearing mode saturates to form a two-dimensional quasisteady state. Third, this secondary equilibrium is itself ideally unstable when it is perturbed by three-dimensional disturbances. Most of this paper is devoted to the analysis and simulation of the three-dimensional linear stability properties of the two-dimensional saturated tearing layer. The numerical simulations are performed with a semi-implicit, pseudospectral-Fourier collocation algorithm. A three-dimensional secondary linear instability that grows on the ideal time scale is identified. An examination of the modal energetics reveals that the largest energy transfer is from the mean field to the three-dimensional field, with the two-dimensional field acting as a catalyst. Results of some high-resolution, fully nonlinear calculations that provide insight into the complete evolution of the system are then presented. During the nonlinear phase, the modes with structure in the third dimension are, in general, more energetic than the purely two-dimensional modes. The evolution is interpreted as being due to a kinking of flux tubes formed during the initial two-dimensional tearing stage. The system reorganizes itself turbulently into a new three-dimensional quasisteady state, which, however, dissipates much more energy than the two-dimensional saturated state. The present work has important implications for a wide range of astrophysical processes that are believed to involve rapid magnetic energy release. C1 USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375. NASA,LANGLEY RES CTR,THEORET FLOW PHYS BRANCH,HAMPTON,VA 23665. RP DAHLBURG, RB (reprint author), USN,RES LAB,COMPUTAT PHYS & FLUID DYNAM LAB,WASHINGTON,DC 20375, USA. RI Antiochos, Spiro/D-4668-2012 OI Antiochos, Spiro/0000-0003-0176-4312 NR 48 TC 58 Z9 58 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD DEC PY 1992 VL 4 IS 12 BP 3902 EP 3914 DI 10.1063/1.860347 PG 13 WC Physics, Fluids & Plasmas SC Physics GA KA787 UT WOS:A1992KA78700010 ER PT J AU LAUNIUS, RD AF LAUNIUS, RD TI NEVER WAS LIFE MORE INTERESTING - THE NATIONAL-ADVISORY-COMMITTEE-FOR-AERONAUTICS, 1936-1945 SO PROLOGUE-QUARTERLY OF THE NATIONAL ARCHIVES LA English DT Article RP LAUNIUS, RD (reprint author), NASA,WASHINGTON,DC 20546, USA. NR 67 TC 0 Z9 0 U1 1 U2 1 PU NATL ARCHIVES PI WASHINGTON PA TRUST FUND BOARD, WASHINGTON, DC 20408 SN 0033-1031 J9 PROLOGUE JI Prologue-Q. Natl. Archives PD WIN PY 1992 VL 24 IS 4 BP 361 EP 373 PG 13 WC History SC History GA KC920 UT WOS:A1992KC92000004 ER PT J AU BINDSCHADLER, R VORNBERGER, P AF BINDSCHADLER, R VORNBERGER, P TI INTERPRETATION OF SAR IMAGERY OF THE GREENLAND ICE-SHEET USING COREGISTERED TM IMAGERY SO REMOTE SENSING OF ENVIRONMENT LA English DT Article AB Landsat Thematic Mapper (TM) images are coregistered with a Seasat Synthetic Aperture Radar (SAR) image of the margin of the Greenland ice sheet and used in the interpretation of features in the SAR data. A winter TM image is used to provide topographic information while a summer TM image provides information on the pattern of melt and the location of lakes. Many previous hypotheses are confirmed, and some are rejected. It is shown that: 1) The snow line is easily detectable in SAR imagery; 2) areas of higher radar backscatter in the bare-ice zone most Often correspond to areas full of crevasses too small to resolve in the SAR image; 3) subsurface scattering causes significant blurring of features in SAR imagery; 4) the band of surface lakes occurring above the snow line corresponds to at least a portion of the wet-snow zone, 5) water is the cause of reduced radar backscatter above the snow line; and 6) the fact that water causes reduced radar backscatter above the snow line permits the use of backscatter variations as a proxy indicator Of surface topography in snow-covered regions experiencing melt. C1 HUGHES STX CORP,LANHAM,MD. RP BINDSCHADLER, R (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 971,GREENBELT,MD 20771, USA. NR 14 TC 11 Z9 11 U1 0 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD DEC PY 1992 VL 42 IS 3 BP 167 EP 175 DI 10.1016/0034-4257(92)90100-X PG 9 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA KF592 UT WOS:A1992KF59200001 ER PT J AU SCAMBOS, TA DUTKIEWICZ, MJ WILSON, JC BINDSCHADLER, RA AF SCAMBOS, TA DUTKIEWICZ, MJ WILSON, JC BINDSCHADLER, RA TI APPLICATION OF IMAGE CROSS-CORRELATION TO THE MEASUREMENT OF GLACIER VELOCITY USING SATELLITE IMAGE DATA SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID ICE AB Image-to-image cross-correlation software is applied to pairs of digital satellite images to map the velocity field of moving ice. This technique uses small-scale glacial surface features, such as crevasse scars and snow dunes, as markers on the surface of the moving ice. Displacements of the surface features are mapped by selecting small image areas centered on distinct features, or by dividing a large area of densely featured glacial surface into a grid of areas, and searching a subsequent image for matching areas using a cross-correlation algorithm. Interpolation of the peak correlation values allows the displacements to be measured to subpixel accuracy, resulting in very precise velocity measurements. Cross-correlation is also applied to provide image coregistration in areas devoid of bedrock exposures. In such areas, subtle large-scale topographic undulations in the ice surface, related to underlying bedrock structure, may be correlated by using large image areas and low-pass filtered images. Both types of applications are demonstrated, using Ice Stream D and Ice Stream E in West Antarctica as test areas. A high-resolution map of the velocity field of the central portion of Ice Stream E, generated by the displacement-measuring technique, is presented. The use of cross-correlation software is a significant improvement over previous manually-based photogrammetric methods for velocity measurement, and is far more cost-effective than in situ methods in remote polar areas. C1 HUGHES STX CORP,LANHAM,MD. MACDONALD DETTWILER,RICHMOND,BC,CANADA. RP SCAMBOS, TA (reprint author), NASA,GODDARD SPACE FLIGHT CTR,OCEANS & ICE BRANCH,CODE 971,GREENBELT,MD 20771, USA. RI Scambos, Ted/B-1856-2009 NR 15 TC 198 Z9 204 U1 2 U2 30 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD DEC PY 1992 VL 42 IS 3 BP 177 EP 186 DI 10.1016/0034-4257(92)90101-O PG 10 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA KF592 UT WOS:A1992KF59200002 ER PT J AU SELLERS, PJ BERRY, JA COLLATZ, GJ FIELD, CB HALL, FG AF SELLERS, PJ BERRY, JA COLLATZ, GJ FIELD, CB HALL, FG TI CANOPY REFLECTANCE, PHOTOSYNTHESIS, AND TRANSPIRATION .3. A REANALYSIS USING IMPROVED LEAF MODELS AND A NEW CANOPY INTEGRATION SCHEME SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID SIMPLE BIOSPHERE MODEL; STOMATAL CONDUCTANCE; NITROGEN; LEAVES; PLANTS; FIELD; ACCLIMATION; RADIATION; CAPACITY; WHEAT AB The theoretical analyses of Sellers (1985; 1987), which linked canopy spectral reflectance properties to (unstressed) photosynthetic rates and conductances, are critically reviewed and significant shortcomings are identified. These are addressed in this article principally through the incorporation of a more sophisticated and realistic treatment of leaf physiological processes within a new canopy integration scheme. It is assumed, based on ecophysiological observations and arguments, that leaf physiological properties vary throughout the plant canopy in response to the radiation-weighted time-mean profile of photosynthetically active radiation (PAR). These modifications yield a simpler and more robust theoretical relationship between canopy biophysical rates (photosynthesis, conductance) and spectral vegetation indices (SVI). The results indicate that area-averaged SVI, as obtained from coarse resolution satellite sensors, may give good estimates of the area-integrals of photosynthesis and conductance even for spatially heterogenous (though physiologically uniform) vegetation covers. C1 CARNEGIE INST WASHINGTON,STANFORD,CA 94305. RP SELLERS, PJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 923,GREENBELT,MD 20771, USA. RI Berry, Joseph/B-8211-2009; collatz, george/D-5381-2012 OI Berry, Joseph/0000-0002-5849-6438; NR 48 TC 545 Z9 580 U1 18 U2 89 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD DEC PY 1992 VL 42 IS 3 BP 187 EP 216 DI 10.1016/0034-4257(92)90102-P PG 30 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA KF592 UT WOS:A1992KF59200003 ER PT J AU MYNENI, RB GANAPOL, BD ASRAR, G AF MYNENI, RB GANAPOL, BD ASRAR, G TI REMOTE-SENSING OF VEGETATION CANOPY PHOTOSYNTHETIC AND STOMATAL CONDUCTANCE EFFICIENCIES SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID RADIATIVE-TRANSFER; REFLECTANCE; TRANSPIRATION; WHEAT; MODEL AB The problem of remote sensing the canopy photosynthetic and stomatal conductance efficiencies is investigated with the aid of one- and three-dimensional radiative transfer methods coupled to a semiempirical mechanistic model of leaf photosynthesis and stomatal conductance. Desertlike vegetation is modeled as clumps of leaves randomly distributed on a bright dry soil with partial ground cover. Normalized difference vegetation index (NDVI), canopy photosynthetic (E(p)), and stomatal efficiencies (E(s)) are calculated for various geometrical, optical, and illumination conditions. A base case is defined to investigate the dynamics of E(p) and E(s) with respect to ground cover, clump leaf area index, soil reflectance, and atmospheric conditions. The contribution of various radiative fluxes to estimates of E(p) is evaluated and the magnitude of errors in bulk canopy formulation of problem parameters are quantifieid. The nature and sensitivity of the relationship between E(p) and E(s) to NDVI is investigated and an algorithm is proposed for use in operational remote sensing. C1 NASA,HEADQUARTERS,WASHINGTON,DC 20546. UNIV ARIZONA,DEPT NUCL & ENERGY ENGN,TUCSON,AZ 85721. RP MYNENI, RB (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HYDROL SCI BRANCH,CODE 974,GREENBELT,MD 20771, USA. RI Myneni, Ranga/F-5129-2012 NR 35 TC 32 Z9 37 U1 2 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD DEC PY 1992 VL 42 IS 3 BP 217 EP 238 DI 10.1016/0034-4257(92)90103-Q PG 22 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA KF592 UT WOS:A1992KF59200004 ER PT J AU KARNI, S AF KARNI, S TI VISCOUS SHOCK PROFILES AND PRIMITIVE FORMULATIONS SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE CONSERVATION LAWS; PRIMITIVE FORMULATIONS; WEAK SOLUTIONS; NUMERICAL VISCOSITY; SHOCK PROFILE ID SCHEMES AB Weak solutions of hyperbolic systems in primitive (nonconservative) form for which a consistent conservation form exists are considered. It is shown that for primitive formulations, shock relations are not uniquely defined by the states to either side of the shock, but also depend on the viscous path connecting the two. Consistent viscous shock profiles are enforced by adding scheme-dependent small viscous perturbations that account for leading order conservation errors. The resulting primitive algorithm is conservative to the order of the approximation. One-dimensional Euler calculations of flows containing weak to moderate shocks show that conservation errors in primitive calculations are substantially reduced by including the viscous perturbation terms. While not eliminating conservation errors entirely, it is found that for a wide range of problems, both conservative and primitive flow calculations are of comparable quality. C1 NASA, LANGLEY RES CTR, INST COMP APPLICAT SCI & ENGN, HAMPTON, VA 23665 USA. RP UNIV MICHIGAN, DEPT MATH, ANN ARBOR, MI 48109 USA. NR 15 TC 25 Z9 26 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 EI 1095-7170 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PD DEC PY 1992 VL 29 IS 6 BP 1592 EP 1609 DI 10.1137/0729092 PG 18 WC Mathematics, Applied SC Mathematics GA KA967 UT WOS:A1992KA96700006 ER PT J AU ADELMAN, HM AF ADELMAN, HM TI EXPERIMENTAL VALIDATION OF THE UTILITY OF STRUCTURAL OPTIMIZATION SO STRUCTURAL OPTIMIZATION LA English DT Article AB This paper addresses the topic of validating structural optimization methods by use of experimental results. The paper describes the need for validating the methods as a way of effecting a greater and an accelerated acceptance of formal optimization methods by practicing engineering designers. The range of validation strategies is defined which includes comparison of optimization results with more traditional design approaches, establishing the accuracy of analyses used, and finally experimental validation of the optimization results. The remainder of the paper describes examples of the use of experimental results to validate optimization techniques. The examples include experimental validation of the following: optimum design of a trussed beam; combined control-structure design of a cable-supported beam simulating an actively controlled space structure; minimum weight design of a beam with frequency constraints; minimization of the vibration response of helicopter rotor blade; minimum weight design of a turbine blade disk; aeroelastic optimization of an aircraft vertical fin; airfoil shape optimization for drag minimization; optimization of the shape of a hole in a plate for stress minimization; optimization to minimize beam dynamic response; and structural optimization of a low vibration helicopter rotor. RP ADELMAN, HM (reprint author), NASA,LANGLEY RES CTR,INTERDISCIPLINARY RES OFF,HAMPTON,VA 23665, USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0934-4373 J9 STRUCT OPTIMIZATION JI Struct. Optim. PD DEC PY 1992 VL 5 IS 1-2 BP 3 EP 11 DI 10.1007/BF01744689 PG 9 WC Computer Science, Interdisciplinary Applications; Engineering, Multidisciplinary; Mechanics SC Computer Science; Engineering; Mechanics GA KC456 UT WOS:A1992KC45600001 ER PT J AU ASTHANA, R ROHATGI, PK AF ASTHANA, R ROHATGI, PK TI MELT INFILTRATION OF SILICON-CARBIDE COMPACTS .1. STUDY OF INFILTRATION DYNAMICS SO ZEITSCHRIFT FUR METALLKUNDE LA English DT Article ID ALUMINUM; COMPOSITES; ALLOYS; METAL; SOLIDIFICATION AB Countergravity, pressure-assisted infiltration with a 2014 Al alloy of suitably tamped porous compacts of platelet shaped single crystals of alpha (hexagonal) silicon carbide was used to measure particulate wettability and infiltration kinetics under dynamic conditions relevant to pressure casting of composites. A threshold pressure (p(th)) for ingression of the infiltrant was identified based on the experimental penetration length versus pressure profiles for a range of experimental variables which included infiltration pressure, infiltration time, SiC size and SiC surface chemistry (plain, Cu coated and Ni coated). The results showed that p(th) decreased whereas the penetration length increased with increasing SiC size and infiltration time. Cu coated SiC led to lower pth (and lower estimated wetting angles) and larger (60 to 80 %) penetration lengths compared to uncoated SiC under identical conditions. These observations have been discussed in the light of theoretical models of infiltration and the kinetics of wetting. C1 UNIV WISCONSIN,DEPT MAT,MILWAUKEE,WI 53211. NASA,LEWIS RES CTR,CLEVELAND,OH 44135. RP ASTHANA, R (reprint author), CLEVELAND STATE UNIV,DEPT CHEM ENGN,E 24TH EUCLID AVE,CLEVELAND,OH 44116, USA. NR 21 TC 20 Z9 20 U1 0 U2 1 PU CARL HANSER VERLAG PI MUNICH PA KOLBERGERSTRASSE 22, POSTFACH 860420, W-8163 MUNICH, GERMANY SN 0044-3093 J9 Z METALLKD JI Z. Metallk. PD DEC PY 1992 VL 83 IS 12 BP 887 EP 892 PG 6 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA KJ298 UT WOS:A1992KJ29800011 ER PT J AU JAVADI, HHS MCGRATH, WR BUMBLE, B LEDUC, HG AF JAVADI, HHS MCGRATH, WR BUMBLE, B LEDUC, HG TI DISPERSION IN NB MICROSTRIP TRANSMISSION-LINES AT SUBMILLIMETER WAVE FREQUENCIES SO APPLIED PHYSICS LETTERS LA English DT Article ID TUNNEL-JUNCTIONS; SIS MIXERS AB We have measured the effects of dispersion on the resonant mode frequencies of open-ended Nb-SiOx-Nb microstrip transmission lines over a frequency range from 50 to 800 GHZ. Submicron Nb/Al-AlOx/Nb Josephson junctions were used as both voltage-controlled oscillators and detectors to sample the high order modes of the resonators. The resonator modes are equally spaced up to about 550 GHz where the mode spacing start to decrease gradually to a minimum above the gap frequency f(g) almost-equal-to 700 GHz and then increases. Results are in good agreement with the expected theoretical behavior based on the Mattis-Bardeen conductivity of the superconductor line. RP JAVADI, HHS (reprint author), JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109, USA. NR 15 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 30 PY 1992 VL 61 IS 22 BP 2712 EP 2714 DI 10.1063/1.108069 PG 3 WC Physics, Applied SC Physics GA JZ892 UT WOS:A1992JZ89200028 ER PT J AU SELLERS, PJ HALL, FG ASRAR, G STREBEL, DE MURPHY, RE AF SELLERS, PJ HALL, FG ASRAR, G STREBEL, DE MURPHY, RE TI AN OVERVIEW OF THE 1ST INTERNATIONAL SATELLITE LAND SURFACE CLIMATOLOGY PROJECT (ISLSCP) FIELD EXPERIMENT (FIFE) SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SIMPLE BIOSPHERE MODEL; TRANSPIRATION; CIRCULATION; PHOTOSYNTHESIS AB In the summer of 1983 a group of scientists working in the fields of meteorology, biology, and remote sensing met to discuss methods for modeling and observing land-surface-atmosphere interactions on regional and global scales. They concluded, first, that the existing climate models contained poor representations of the processes controlling the exchanges of energy, water, heat, and carbon between the land surface and the atmosphere and, second, that satellite remote sensing had been underutilized as a means of specifying global fields of the governing biophysical parameters. Accordingly, a multiscale, multidisciplinary experiment, FIFE, was initiated to address these two issues. The objectives of FIFE were specified as follows: (1) Upscale integration of models: The experiment was designed to test the soil-plant-atmosphere models developed by biometeorologists for small-scale applications (millimeters to meters) and to develop methods to apply them at the larger scales (kilometers) appropriate to atmospheric models and satellite remote sensing. (2) Application of satellite remote sensing: Even if the first goal were achieved to yield a "perfect" model of vegetation-atmosphere exchanges, it would have very limited applications without a global observing system for initialization and validation. As a result, the experiment was tasked with exploring methods for using satellite data to quantify important biophysical states and rates for model input. The experiment was centered on a 15 x 15 km grassland site near Manhattan, Kansas. This area became the focus for an extended monitoring program of satellite, meteorological, biophysical, and hydrological data acquisition from early 1987 through October 1989 and a series of 12- to 20-day intensive field campaigns (IFCs), four in 1987 and one in 1989. During the IFCs the fluxes of heat, moisture, carbon dioxide, and radiation were measured with surface and airborne equipment in coordination with measurements of surface and atmospheric parameters and satellite overpasses. The resulting data are held in a single integrated data base and continue to be analyzed by the participating scientists and others. The first two sections of this paper recount the history and scientific background leading up to FIFE; the third and fourth sections review the experiment design, the scientific teams and equipment involved, and the actual execution of the experiment; the fifth section provides an overview of the contents of this special issue; the sixth section summarizes the management and resources of the project; and the last section lists the acknowledgments C1 NASA HEADQUARTERS,WASHINGTON,DC 20546. VERSAR INC,COLUMBIA,MD 21045. RP SELLERS, PJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 923,GREENBELT,MD 20771, USA. NR 41 TC 313 Z9 326 U1 3 U2 20 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18345 EP 18371 PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000001 ER PT J AU CROSSON, WL SMITH, EA AF CROSSON, WL SMITH, EA TI ESTIMATION OF SURFACE HEAT AND MOISTURE FLUXES OVER A PRAIRIE GRASSLAND .2. 2-DIMENSIONAL TIME FILTERING AND SITE VARIABILITY SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB The behavior of in situ measurements of surface fluxes obtained during FIFE 1987 is examined by using correlative and spectral techniques in order to assess the significance of fluctuations on various time scales, from subdiurnal up to synoptic, intraseasonal, and annual scales. The objectives of this analysis are (1) to determine which temporal scales have a significant impact on areal averaged fluxes and (2) to design a procedure for filtering an extended flux time series that preserves the basic diurnal features and longer time scales while removing high frequency noise that cannot be attributed to site-induced variation. These objectives are accomplished through the use of a two-dimensional cross-time Fourier transform, which serves to separate processes inherently related to diurnal and subdiurnal variability from those which impact flux variations on the longer time scales. A filtering procedure is desirable before the measurements are utilized as input with an experimental biosphere model, to insure that model based intercomparisons at multiple sites are uncontaminated by input variance not related to true site behavior. Analysis of the spectral decomposition indicates that subdiurnal time scales having periods shorter than 6 hours have little site-to-site consistency and therefore little impact on areal integrated fluxes. The spectral filter has thus been designed to remove these modes. Application of the filter to the 143-day FIFE 1987 flux records results in time series that retain at least 90% of the original variance and preserve the slower diurnal and longer time scales. C1 FLORIDA STATE UNIV,SUPERCOMP COMPUTAT RES INST,TALLAHASSEE,FL 32306. FLORIDA STATE UNIV,DEPT METEOROL,TALLAHASSEE,FL 32306. RP CROSSON, WL (reprint author), UNIV SPACE RES ASSOC,MARSHALL SPACE FLIGHT CTR,HUNTSVILLE,AL 35812, USA. NR 8 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18583 EP 18598 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000020 ER PT J AU SMITH, EA HSU, AY CROSSON, WL FIELD, RT FRITSCHEN, LJ GURNEY, RJ KANEMASU, ET KUSTAS, WP NIE, D SHUTTLEWORTH, WJ STEWART, JB VERMA, SB WEAVER, HL WESELY, ML AF SMITH, EA HSU, AY CROSSON, WL FIELD, RT FRITSCHEN, LJ GURNEY, RJ KANEMASU, ET KUSTAS, WP NIE, D SHUTTLEWORTH, WJ STEWART, JB VERMA, SB WEAVER, HL WESELY, ML TI AREA-AVERAGED SURFACE FLUXES AND THEIR TIME-SPACE VARIABILITY OVER THE FIFE EXPERIMENTAL DOMAIN SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ENERGY BUDGET MICROCLIMATES; DEEP VALLEY RADIATION; BOUNDARY-LAYER; IMPACT; SOIL; EVAPOTRANSPIRATION; CIRCULATIONS; BALANCE; HEAT AB The underlying mean and variance properties of surface net radiation, soil heat flux, and sensible-latent heat fluxes are examined over the densely instrumented grassland region encompassing the First ISLSCP Field Experiment (FIFE). Twenty-two surface flux stations at 20 sites were deployed during the four 1987 intensive field campaigns (IFCs). Flux variability is addressed together with the problem of scaling up to area-averaged fluxes. Successful parameterization of area-averaged fluxes in atmospheric models is based on accounting for internal spatial and temporal scales correctly. Mean and variance properties of fluxes are examined in both daily and diurnally averaged frameworks. Results are compared and contrasted for clear and cloudy situations and checked for the influence of surface-induced biophysical controls (burn and grazing treatments) and topographic controls (slope factors and aspect ratios). Examination of the sensitivity of domain-averaged fluxes to different averaging procedures demonstrates that this may be an important consideration. The results reveal six key features of the 1987 surface fluxes: (1) cloudiness variability and ample rainfall throughout the growing season led to near-consistency in flux magnitudes during the first three IFCs; (2) burn treatment, grazing conditions, and topography have clearly delineated influences on the diurnal cycle flux amplitudes but do not alter the evaporative fraction significantly; (3) cloudiness is the major control on flux variability in terms of both mean and variance properties but has little impact on the Bowen ratio or evaporative fraction; (4) spatial weighting of fluxes based on a biophysical-topographical cross stratification generates a measurable bias with respect to straight arithmetic averaging (up to 20 W m-2 in available heating); (5) structure function analysis demonstrates significant underlying spatial autocorrelation structure in the fluxes, but the observed distance dependence is due to cloudiness controls, not surface controls; (6) Monte Carlo analysis of high resolution vegetation indices obtained from SPOT satellite measurements suggest that the mean domain amplitudes of the diurnal sensible and latent heat flux cycles can be biased up to 30-40 W m-2 by repositioning the 20 site locations within the experimental domain. C1 FLORIDA STATE UNIV, SUPERCOMP COMPUTAT RES INST, TALLAHASSEE, FL 32306 USA. NASA, GODDARD SPACE FLIGHT CTR, GREENBELT, MD 20771 USA. UNIV DELAWARE, COLL MARINE, NEWARK, DE 19718 USA. UNIV WASHINGTON, COLL FOREST RESOURCES, SEATTLE, WA 98195 USA. UNIV GEORGIA, DEPT AGRON, GRIFFIN, GA 30223 USA. USDA ARS, BELTSVILLE AGR RES CTR, BELTSVILLE, MD 20705 USA. KANSAS STATE UNIV AGR & APPL SCI, EVAPOTRANSPIRAT LAB, MANHATTAN, KS 66506 USA. INST HYDROL, WALLINGFORD OX10 8BB, OXON, ENGLAND. UNIV NEBRASKA, CTR AGR METEOROL & CLIMATOL, LINCOLN, NE 68588 USA. US GEOL SURVEY, DENVER, CO 80225 USA. ARGONNE NATL LAB, DIV ENVIRONM RES, ARGONNE, IL 60439 USA. RP SMITH, EA (reprint author), FLORIDA STATE UNIV, DEPT METEOROL, TALLAHASSEE, FL 32306 USA. NR 45 TC 91 Z9 93 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18599 EP 18622 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000021 ER PT J AU HALTHORE, RN MARKHAM, BL AF HALTHORE, RN MARKHAM, BL TI OVERVIEW OF ATMOSPHERIC CORRECTION AND RADIOMETRIC CALIBRATION EFFORTS DURING FIFE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOLAR IRRADIANCE; REFLECTANCE; SCATTERING; ABSORPTION; AVHRR AB The primary responsibility within the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) for understanding the radiometric properties of the remote sensing instrumentation and the atmospheric optical proper-ties affecting measurements with these instruments rested within the atmospheric corrections and radiometric calibration subgroup of FIFE, called the correction/calibration group for short. Specific activities included (1) calibration of remote sensing instrumentation used on aircraft and surface platforms, (2) formulation of recommendations for calibrating data from satellite sensors, (3) measurement and analysis of atmospheric properties, (4) development and evaluation of radiative transfer algorithms which per-form the atmospheric correction of remotely sensed data, and (5) derivation and evaluation of surface properties such as reflectances and temperatures. A review of the activities performed by this group and a discussion of the importance of these activities in retrieving surface parameters is presented here. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP HALTHORE, RN (reprint author), HUGHES STX,LANHAM,MD, USA. RI Markham, Brian/M-4842-2013 OI Markham, Brian/0000-0002-9612-8169 NR 41 TC 6 Z9 6 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18731 EP 18742 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000032 ER PT J AU BRUEGGE, CJ HALTHORE, RN MARKHAM, B SPANNER, M WRIGLEY, R AF BRUEGGE, CJ HALTHORE, RN MARKHAM, B SPANNER, M WRIGLEY, R TI AEROSOL OPTICAL DEPTH RETRIEVALS OVER THE KONZA PRAIRIE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOLAR; CALIBRATION AB The aerosol optical depth over the Konza Prairie, near Manhattan, Kansas, was recorded at various locations by five separate teams. These measurements were made in support of the First ISLSCP Field Experiment (FIFE) and used to correct imagery from a variety of satellite and aircraft sensors for the effects of atmospheric scattering and absorption. The results from one instrument are reported here for 26 days in 1987 and for 7 days in 1989. Daily averages span a range of 0.05 to 0.28 in the midvisible wavelengths. In addition, diurnal variations are noted in which the afternoon optical depths are greater than those of the morning by as much as 0.07. A comparison between instruments and processing techniques used to determine these aerosol optical depths is provided. The first comparisons are made using summer 1987 data. Differences of as much as 0.05 (midvisible) are observed. Although these data allow reasonable surface reflectance retrievals, they do not agree to within the performance limits typically associated with these types of instruments With an accuracy goal of 0.02 a preseason calibration/comparison experiment was conducted at a mountain site prior to the final field campaign in 1989. Good calibration data were obtained, and good agreement (0.01, midvisible) was observed in the retrieved optical depth acquired over the Konza. By comparing data from the surface instruments at different locations, spatial inhomogeneities are determined. Then, data from the airborne tracking sunphotometer allow one to determine variations as a function of altitude. Finally, a technique is proposed for using the in situ data to establish an instrument calibration. C1 ST SYST CORP,LANHAM,MD. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RP BRUEGGE, CJ (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. RI Markham, Brian/M-4842-2013 OI Markham, Brian/0000-0002-9612-8169 NR 34 TC 20 Z9 21 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18743 EP 18758 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000033 ER PT J AU BRUEGGE, CJ CONEL, JE GREEN, RO MARGOLIS, JS HOLM, RG TOON, G AF BRUEGGE, CJ CONEL, JE GREEN, RO MARGOLIS, JS HOLM, RG TOON, G TI WATER-VAPOR COLUMN ABUNDANCE RETRIEVALS DURING FIFE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB A variation of the modified Langley plot algorithm is reported here and applied to the retrieval of atmospheric water column abundance from a filtered sunphotometer. In this new methodology an absorption data base (LOWTRAN 7) is used to compute a water abundance versus transmittance curve of growth, rather than the square-root dependence previously assumed. Validation of the technique is provided from an uncertainty analysis, and plans to further validate using Fourier transform spectrometers are detailed. The new sunphotometer technique is used to report total column water vapor during the First ISLSCP Field Experiment (FIFE), and comparisons are made with abundances retrieved via FIFE radiosonde observations. The sunphotometer data can best be utilized, however, to in tum validate data from airborne or in-orbit measurements of water vapor. With these flight sensors, horizontal and topographic variability within the scene can be viewed. An example of the airborne data set is given using an image from the airborne visible infrared imaging spectrometer (AVIRIS), as acquired on August 31, 1990. RP BRUEGGE, CJ (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 17 TC 84 Z9 90 U1 2 U2 15 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18759 EP 18768 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000034 ER PT J AU HALTHORE, RN MARKHAM, BL FERRARE, RA ARO, TO AF HALTHORE, RN MARKHAM, BL FERRARE, RA ARO, TO TI AEROSOL OPTICAL-PROPERTIES OVER THE MIDCONTINENTAL UNITED-STATES SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SIZE DISTRIBUTIONS; RELATIVE-HUMIDITY; EXTINCTION; ATMOSPHERE AB Solar and sky radiation measurements were analyzed to obtain aerosol properties such as the optical thickness and the size distribution. The measurements were conducted as part of the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) during the second intensive field campaign (IFC) from June 25 to July 14, 1987, and the fifth IFC from July 25 to August 12, 1989, on the Konza Prairie near Manhattan, Kansas. Correlations with climatological and meteorological parameters show that during the period of observations in 1987, two types of air masses dominated the area: an air mass with low optical thickness and low temperature air associated with a northerly breeze, commonly referred to as the continental air, and an air mass with a higher optical thickness and higher temperature air associated with a southerly wind which we call "Gulf air." The size distributions show a predominance of the larger size particles in Gulf air. Because of the presence of two contrasting air masses, correlations with parameters such as relative humidity, specific humidity, pressure, temperature, and North Star sky radiance reveal some interesting aspects. In 1989, clear distinctions between continental and Gulf air cannot be made; the reason for this will be discussed. C1 NASA,GODDARD SPACE FLIGHT CTR,USRA,GREENBELT,MD 20771. UNIV ILORIN,DEPT PHYS,ILORIN,NIGERIA. RP HALTHORE, RN (reprint author), HUGHES STX CORP,LANHAM,MD, USA. RI Markham, Brian/M-4842-2013 OI Markham, Brian/0000-0002-9612-8169 NR 31 TC 21 Z9 22 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18769 EP 18778 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000035 ER PT J AU MARKHAM, BL HALTHORE, RN GOETZ, SJ AF MARKHAM, BL HALTHORE, RN GOETZ, SJ TI SURFACE REFLECTANCE RETRIEVAL FROM SATELLITE AND AIRCRAFT SENSORS - RESULTS OF SENSOR AND ALGORITHM COMPARISONS DURING FIFE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CANOPY REFLECTANCE; ATMOSPHERE AB Visible to shortwave infrared radiometric data collected by a number of remote sensing instruments on aircraft and satellite platforms were compared over common areas in the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) site on August 4, 1989, to assess their radiometric consistency and the adequacy of atmospheric correction algorithms. The instruments in the study included the Landsat 5 thematic mapper (TM), the SPOT 1 high-resolution visible (HRV) 1 sensor, the NS001 thematic mapper simulator, and the modular multispectral radiometers (MMRs). Atmospheric correction routines analyzed were an algorithm developed for FIFE, LOWTRAN 7, and 5S. A comparison between corresponding bands of the SPOT 1 HRV 1 and the Landsat 5 TM sensors indicated that the two instruments were radiometrically consistent to within about 5%. Retrieved surface reflectance factors using the FIFE algorithm over one site under clear atmospheric conditions indicated a capability to determine near-nadir surface reflectance factors to within about 0.01 at a reflectance of 0.06 in the visible (0.4-0.7 mum) and about 0.30 in the near infrared (0.7-1.2 mum) for all but the NS001 sensor. All three atmospheric correction procedures produced absolute reflectances to within 0.005 in the visible and near infrared. In the shortwave infrared (1.2-2.5 mum) region the three algorithms differed in the retrieved surface reflectances primarily owing to differences in predicted gaseous absorption. Although uncertainties in the measured surface reflectance in the shortwave infrared precluded definitive results, the 5S code appeared to predict gaseous transmission marginally more accurately than LOWTRAN 7. C1 HUGHES STX CORP,LANHAM,MD. RP MARKHAM, BL (reprint author), NASA,GODDARD SPACE FLIGHT CTR,BIOSPHER SCI BRANCH,GREENBELT,MD 20771, USA. RI Markham, Brian/M-4842-2013; Goetz, Scott/A-3393-2015 OI Markham, Brian/0000-0002-9612-8169; Goetz, Scott/0000-0002-6326-4308 NR 33 TC 21 Z9 22 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18785 EP 18795 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000037 ER PT J AU WRIGLEY, RC SPANNER, MA SLYE, RE PUESCHEL, RF AGGARWAL, HR AF WRIGLEY, RC SPANNER, MA SLYE, RE PUESCHEL, RF AGGARWAL, HR TI ATMOSPHERIC CORRECTION OF REMOTELY SENSED IMAGE DATA BY A SIMPLIFIED MODEL SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SCATTERING; RADIATION AB The interaction of radiation with the atmosphere is complex and has proved difficult to calculate without reference to measurements made at or close to the time and location of interest. In this paper we describe the use of data from an airborne-tracking sunphotometer mounted on a NASA C-130 aircraft to derive optical properties of the atmospheric aerosols above the aircraft when it is on the ground as well as when the aircraft is at altitude collecting remote sensing data. Furthermore, we describe the use of these optical properties for quantitative atmospheric correction of Landsat thematic mapper (TM) and NS001 TM simulator radiances in a simplified radiative transfer model appropriate for each pixel of entire images. Both qualitative and quantitative comparisons of results from use of the model show it provides good to excellent correction for atmospheric effects in TM and NS001 TM simulator data. Quantitative comparisons with measurements of surface radiances measured near the time of the TM overpass showed agreement within a few percent for bands 2, 3, and 4. Band 1 yielded radiances within 15% of the surface radiances. We think the simplified atmospheric correction model shows great promise for applying atmospheric corrections to entire images instead of individual points within images to yield surface radiances within a few percent in a computationally efficient manner. C1 TGS TECHNOL INC,COLORADO SPRINGS,CO. STERLING SOFTWARE INC,DALLAS,TX. RP WRIGLEY, RC (reprint author), NASA,AMES RES CTR,MOFFETT FIELD,CA 94035, USA. NR 28 TC 12 Z9 12 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18797 EP 18814 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000038 ER PT J AU AHMAD, SP MARKHAM, BL AF AHMAD, SP MARKHAM, BL TI RADIOMETRIC CALIBRATION OF A POLARIZATION-SENSITIVE SENSOR SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ATMOSPHERE; AEROSOLS; RADIANCE; LIGHT AB The radiometric accuracy of a sensor is adversely affected by scene polarization if its optical system is sensitive to polarization. Tests performed on the reflective bands of the NS001 thematic mapper simulator, an aircraft multispectral scanner, show that it is very sensitive to the polarization state of the incoming radiations. For 100% linearly polarized light, errors in the measured intensity vary from -40 to +40%, depending on the scan angle and spectral band. To estimate polarization-induced errors in the intensity measured at aircraft level, the intensity and polarization of the atmospheric radiances were simulated using a realistic Earth-atmosphere radiative transfer model. For the polarization of atmospheric radiances in the solar meridian plane over a vegetated target, intensity errors may range from -10 to +10%. The polarization-induced errors are highest in the shortest NS001 spectral band (0.450-0.525 mum) because of large atmospheric polarizations contributed by Rayleigh particles and small diluting effects caused by the small contributions of weakly polarized radiations coming from aerosols and the surface. Depending on the illumination and view angles, the errors in derived surface reflectance due to the radiance errors can be very large. In particular, for large off-nadir view angles in the forward scattered direction when the Sun is low, the relative errors in the derived surface reflectance can be as large as 4 to 5 times the relative error in the radiances. Polarization sensitivity errors cannot be neglected for the shorter wavelengths when the surface reflectance contribution to atmospheric radiances is very small. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP AHMAD, SP (reprint author), HUGHES STX CORP,LANHAM,MD, USA. RI Markham, Brian/M-4842-2013 OI Markham, Brian/0000-0002-9612-8169 NR 38 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18815 EP 18827 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000039 ER PT J AU AHMAD, SP DEERING, DW AF AHMAD, SP DEERING, DW TI A SIMPLE ANALYTICAL FUNCTION FOR BIDIRECTIONAL REFLECTANCE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIATIVE-TRANSFER MODEL; CANOPY REFLECTANCE; PHYSICAL MODEL; NIMBUS-7 ERB; BARE SOIL; SURFACES; SPECTROSCOPY; ATMOSPHERE; SCATTERING; POLARIZATION AB A simple bidirectional reflectance model based on physical scattering laws is developed to calculate the bidirectional reflectance of a wide variety of surfaces. Chandrasekhar's radiative transfer solution, obtained for the anisotropically scattering semi-infinite medium, is used to compute the multiple-scattered radiances. However, since the radiative transfer solution does not take architectural effects into consideration, we adopt Hapke's (1986) approach and add an empirical term to explain the hot-spot phenomenon and use Cox and Munk's (1954) formulation to take into account the specular reflection. The physical parameters of the model are retrieved from bidirectional reflectance measurements. For each surface, only one set of model parameters is needed for application to all illumination and viewing geometries. The validity of the model is established by comparing the computed and measured reflectances for sets of viewing and illumination angles that were not included in the inversion algorithm. Good agreement is shown between the model-computed and the observed reflectances for dense prairie vegetation canopies, a sparse desert scrub community, a plowed agricultural field, and an alkali flat. C1 NASA,GODDARD SPACE FLIGHT CTR,TERR PHYS LAB,BIOSPHER SCI BRANCH,GREENBELT,MD 20771. RP AHMAD, SP (reprint author), HUGHES STX CORP,LANHAM,MD, USA. NR 70 TC 60 Z9 60 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18867 EP 18886 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000044 ER PT J AU DEERING, DW MIDDLETON, EM IRONS, JR BLAD, BL WALTERSHEA, EA HAYS, CJ WALTHALL, C ECK, TF AHMAD, SP BANERJEE, BP AF DEERING, DW MIDDLETON, EM IRONS, JR BLAD, BL WALTERSHEA, EA HAYS, CJ WALTHALL, C ECK, TF AHMAD, SP BANERJEE, BP TI PRAIRIE GRASSLAND BIDIRECTIONAL REFLECTANCES MEASURED BY DIFFERENT INSTRUMENTS AT THE FIFE SITE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIANCE; SKY AB Land surface reflectance measurements were acquired during the First ISLSCP Field Experiment (FIFE) field campaigns using a variety of ground-based and airborne spectral radiometers. To examine the validity of the assumption that the values acquired by the several different instruments and teams were interchangeable, the surface radiation measurement teams converged on a common site for 1 day during the fifth intensive field campaign (IFC 5) in 1989. The instruments compared for near-surface measurements included two ground-based Spectron Engineering SE590s, one helicopter-mounted SE590, one ground-based and one helicopter-mounted Barnes modular multiband radiometer (MMR), and the portable apparatus for rapid acquisitions of bidirectional observations of land and atmosphere (PARABOLA) field radiometer. Comparisons were made for nadir measurements over a range of solar zenith angles and a range of off-nadir viewing angles. The bidirectional reflectances from the different instruments were generally found to be quite comparable. For example, for a 52-degrees solar zenith angle, the nadir red and near-infrared spectral reflectance factors ranged from 3.5 to 4.5% and 28.2 to 31.9%, respectively. At the smaller solar zenith angles, however, the differences were somewhat greater (red, 4.5-6.1%; near-infrared (NIR), 25.0-28.9%), and the coefficients of variation for the samples taken by all of the instruments increased. Off-nadir viewing caused major departures from nadir bidirectional reflectances (30% reflectance at nadir compared with 55% at 60-degrees off nadir in the NIR, for example), but all of the instruments captured the effects reasonably well. Spectral vegetation indices were found to have a considerable dependence on both solar zenith angle and sensor viewing angle. In spite of the general agreement between most instruments and teams, the lack of a more consistent band-to-band agreement resulted in appreciable differences in the spectral vegetation index values, which could potentially affect the accuracy and precision of remote sensing assessments of biophysical parameters. C1 UNIV NEBRASKA,DEPT AGR METEOROL,LINCOLN,NE 68588. UNIV MARYLAND,DEPT GEOG,COLL PK,MD 20742. HUGHES STX CORP,LANHAM,MD. RP DEERING, DW (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. RI ECK, THOMAS/D-7407-2012; Irons, James/D-8535-2012 NR 23 TC 49 Z9 50 U1 0 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18887 EP 18903 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000045 ER PT J AU WALTHALL, CL MIDDLETON, EM AF WALTHALL, CL MIDDLETON, EM TI ASSESSING SPATIAL AND SEASONAL-VARIATIONS IN GRASSLANDS WITH SPECTRAL REFLECTANCES FROM A HELICOPTER PLATFORM SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID VEGETATION AB Helicopter-based radiometric measurements of grassland sites were acquired during the first International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) to quantify the spatial and spectral variations in surface reflectance contributing to variations in albedo and for comparison with surface fluxes. The helicopter instrumentation consisted of an eight-channel modular multiband radiometer (MMR), video, and photographic cameras. Seasonal and spatial variability of the entire FIFE study area were characterized using 20 MMR data sets from five FIFE sites during the four best ("Golden") data collection days of 1987. The means and coefficients of variation for each spectral band were calculated and analyzed as a function of spatial and seasonal domains. Linear models describing simple ratio SR) and normalized difference vegetation index (NDVI) as functions of several surface variables were tested. All eight MMR bands contributed information beneficial for characterizing spatial and temporal variations, and the most useful bands were the red (MMR3, 0.634).68 mum) and the third middle infrared (MMR7, 2.08-2.37 mum). The blue band (MMR1, 0.45-0.52 mum) proved to be valuable, whereas the often utilized near infrared band (MMR4, 0.75-0.88 mum) was among the least important bands for discriminating landscape variations. The SR was more sensitive than the NDVI to variations in the Konza grassland at all scales: intrasite and intersite, between management practices of burning ind grazing, and over time furthermore, the relationship of the NDVI with leaf area index was curvilinear, whereas the relationship of the SR was linear at low-leaf area index and was improved by the addition of a second variable, the percent of green dry weight biomass. Improvements in data collection methodologies arc recommended for future large scale experiments such as the Boreal Ecosystem and Atmosphere Study (BOREAS). C1 NASA,GODDARD SPACE FLIGHT CTR,BIOSPHER SCI BRANCH,GREENBELT,MD 20771. RP WALTHALL, CL (reprint author), UNIV MARYLAND,DEPT GEOG,GLOBAL REMOTE SENSING STUDIES LAB,COLL PK,MD 20742, USA. NR 22 TC 20 Z9 20 U1 2 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18905 EP 18912 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000046 ER PT J AU JEDLOVEC, GJ ATKINSON, RJ AF JEDLOVEC, GJ ATKINSON, RJ TI VARIABILITY OF GEOPHYSICAL PARAMETERS FROM AIRCRAFT RADIANCE MEASUREMENTS FOR FIFE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SEA-SURFACE TEMPERATURE; AVHRR AB Airborne multispectral images were collected on 2 days during the First ISLSCP Field Experiment (FIFE) to investigate the time and space variability of remotely sensed geophysical parameters over the study region. The data sets consisted of multiple overflights covering about a 60-min period during late morning on June 4, 1987, and shortly after dark on the following day. Image data from each overpass were calibrated and Earth-located with respect to each other using aircraft inertial navigation system parameters and ground control points. Normalized difference vegetation index (NDVI) values were generated from visible and near-infrared imagery to characterize the greenness of the vegetation, its spatial variability, and its variation with changing sensor-Sun-viewing geometries. Land surface temperatures (LST) were derived using a split-window formulation to investigate their spatial and temporal variability in relation to the NDVI values and other surface features and the variability between day and night observations. The results indicated that large variations in these parameters existed at small scales. Variability in NDVI values was large and was governed by the natural surface character and its use. Large variations of NDVI occurred with different sensor-Sun-viewing geometries as a result of anisotropic reflection from the surface, atmospheric interference, and slope and aspect effects. LST was also highly varied. Positive land surface temperature changes, as a result of excess absorption of solar radiation, exceeded 4-degrees-C in 45 min over certain regions and were governed by land use and microtopography. Smaller negative temperature changes were observed at night. NDVI and LST values were inversely related, with fairly high correlations for certain surface features. The unique multispectral atmospheric mapping sensor (MAMS) measurements and the derived NDVI and LST data provided a better understanding of reflective and thermal properties within a heterogeneous region, as well as a quantitative description of their spatial and temporal variability, and served to better characterize important surface processes related to microclimate variability. C1 GE,HUNTSVILLE,AL. RP JEDLOVEC, GJ (reprint author), NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,REMOTE SENSING BRANCH,HUNTSVILLE,AL 35812, USA. NR 22 TC 7 Z9 7 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18913 EP 18924 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000047 ER PT J AU WALTERSHEA, EA BLAD, BL HAYS, CJ MESARCH, MA DEERING, DW MIDDLETON, EM AF WALTERSHEA, EA BLAD, BL HAYS, CJ MESARCH, MA DEERING, DW MIDDLETON, EM TI BIOPHYSICAL PROPERTIES AFFECTING VEGETATIVE CANOPY REFLECTANCE AND ABSORBED PHOTOSYNTHETICALLY ACTIVE RADIATION AT THE FIFE SITE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BIDIRECTIONAL REFLECTANCE; DIRECTIONAL REFLECTANCE; LEAF-ORIENTATION; SPECTRAL REFLECTANCE; COTTON LEAVES; CORN LEAVES; VIEW ANGLE; SUN ANGLE; TRANSMITTANCE; SCATTERING AB Leaves of the dominant grass species of the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) site reflect and transmit radiation in a similar manner to other healthy green leaves. Visible reflectance factors (RFs) and transmittance factors (TFs) were lower for older leaves than younger leaves except during senescence, when RF and TF values were higher. Near-infrared (NIR) RF values increased and TF values decreased with leaf age, with the reverse occurring as the leaf underwent senescence. Leaf optical properties were not found to be dependent on leaf water potential in the range from -0.5 to -3.0 MPa. Canopy bidirectional reflectance factor (BRF) values generally increased with increasing view zenith angle (theta(v)). Maximum values were in the backscatter direction, whereas BRF values in the visible region were lowest at oblique off-nadir theta(v) in the forward scatter direction and at or near nadir in the NIR region. Solar principal plane BRF values varied most at large solar zenith angles (theta(s)). Visible and mid-infrared canopy BRF values decreased and NIR BRF values increased with leaf area index (LAI). Soil BRF distributions in the solar principal plane varied slightly with theta(s) and theta(v) and varied considerably for wet and dry surfaces. Spectral vegetation indices (SVIs) varied with theta(s) and theta(v); values were lowest in the backscatter direction and highest in the forward scatter direction. The fraction of absorbed photosynthetically active radiation (APAR) increased with increasing theta(s). APAR had a strong linear relationship to nadir-derived SVI values but not to oblique off-nadir-derived SVI values. The relatively small dependence of off-nadir SVI values on theta(s) should allow daily APAR values to be estimated from measurements made at any time of the day. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP WALTERSHEA, EA (reprint author), UNIV NEBRASKA,DEPT AGR METEOROL,LINCOLN,NE 68588, USA. NR 39 TC 45 Z9 45 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18925 EP 18934 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000048 ER PT J AU MIDDLETON, EM AF MIDDLETON, EM TI QUANTIFYING REFLECTANCE ANISOTROPY OF PHOTOSYNTHETICALLY ACTIVE RADIATION IN GRASSLANDS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOLAR ZENITH ANGLE; LEAF-AREA INDEX; SPECTRAL REFLECTANCE; CANOPY REFLECTANCE; BIDIRECTIONAL REFLECTANCE; HEMISPHERICAL REFLECTANCE; SURFACE REFLECTANCE; CORN CANOPIES; WHEAT; NADIR AB The fraction of photosynthetically active radiation (PAR) (lambda = 0.4-0.7 mum) absorbed (F(APAR)) is a critical parameter in canopy processes and in land surface-atmosphere interactions. F(APAR) is typically inferred indirectly through empirical relationships established between hemispheric measurements of PAR and either (1) canopy bidirectional, usually nadir, reflectances in the visible wavelengths or (2) spectral vegetation indices. However, the bidirectional reflectance distribution function (BRDF) of vegetated surfaces has been shown to exhibit angular and spectral anisotropy, complicating the estimation of average surface reflectances, including that of PAR, from remote observations. Quantifying the surface's reflectance anisotropy was an important element of the First ISLSCP Field Experiment (FIFE), since its major objectives focused on retrieval of surface parameters from satellite-derived reflectances. Prior to the experiment reported here, the explicit remote measurements for approximating the BRDF of PAR had not been undertaken. The proper expression of reflectance for BRDFs for retrieval of canopy parameters is assessed. A rationale is given for the expression of reflectances as bidirectional reflectance fractions (RFRs), instead of the conventional bidirectional reflectance factors (RFs), when relating spectral data tc canopy states or processes. The characterization of the grassland anisotropy in the solar principal plane is markedly different when expressed as RFRs versus RFs. Whereas RFs are extremely useful in addressing important "remote sensing" issues, the "surface only" BRDF is obscured by pixel-size effects since the projected viewing area increases by a factor of cos(theta(V))-1 with view angle (theta(V)) for off-nadir views. The BRDF for RFRs exhibited increased absorption by the canopy in the forward scatter directions; the anisotropy is most pronounced at midday, and more isotropic at intermediate sun angles, at which time the nadir observation was adequate for estimating the mean surface PAR reflectance. RP MIDDLETON, EM (reprint author), NASA,GODDARD SPACE FLIGHT CTR,TERR PHYS LAB,BIOSPHER SCI BRANCH,GREENBELT,MD 20771, USA. NR 52 TC 9 Z9 9 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18935 EP 18946 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000049 ER PT J AU WANG, JR AF WANG, JR TI AN OVERVIEW OF THE MEASUREMENTS OF SOIL-MOISTURE AND MODELING OF MOISTURE FLUX IN FIFE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MICROWAVE EMISSION AB Measurements of soil moisture and calculations of moisture transfer in the soil medium and at the air-soil interface were conducted by a group of investigators over a 15-km by 15-km test site south of Manhattan, Kansas, during the First ISLSCP Field Experiment (FIFE) in 1987 and 1989. The measurements included intensive soil moisture sampling at the ground level and surveys at aircraft altitudes by several active and passive microwave sensors as well as a gamma radiation device. The calculations were based on a catchment-scale water balance model that is driven by spatially interpolated rainfalls and estimated potential evaporation. The results of this group effort are presented in the five papers in this section. They include discussions on the statistics of soil moisture variability within a pixel of a remote sensor, soil moisture measurements by impedance probes, the comparison of active and passive microwave sensing of surface soil moisture, the statistics of soil moisture estimation by a gamma-radiation technique, and the comparison of the calculated and measured latent heat fluxes at the catchment scale (4 km by 4 km). RP WANG, JR (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HYDROSPHER PROC LAB,GREENBELT,MD 20771, USA. NR 18 TC 6 Z9 6 U1 2 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18955 EP 18959 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000052 ER PT J AU UNGAR, SG LAYMAN, R CAMPBELL, JE WALSH, J MCKIM, HJ AF UNGAR, SG LAYMAN, R CAMPBELL, JE WALSH, J MCKIM, HJ TI DETERMINATION OF SOIL-MOISTURE DISTRIBUTION FROM IMPEDANCE AND GRAVIMETRIC MEASUREMENTS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB Daily measurements of the soil dielectric properties at 5 and 10 cm were obtained at five locations throughout the First ISLSCP Field Experiment (FIFE) test site during the 1987 intensive field campaigns (IFCs). An automated vector voltmeter was used to monitor the complex electrical impedance, at 10 MHz, of cylindrical volumes of soil delineated by specially designed soil moisture probes buried at these locations. The objective of this exercise was to test the hypothesis that the soil impedance is sensitive to the moisture content of the soil and that the imaginary part (that is, capacitive reactance) can be used to calculate the volumetric water content of the soil. These measurements were compared with gravimetric samples collected at these locations by the FIFE staff science team. In addition to the five fixed locations, measurements were made throughout each of the IFCs along three transects underlying airborne push broom microwave radiometer (PBMR) flights and compared with the results of gravimetric sampling done in support of these flights. Examination of the data reveals that the impedance probe is a more consistent source of time series information than traditional measurements and is potentially more closely linked to the physical parameters which are both remotely sensible and required for surface energy/mass exchange determination. C1 DARTMOUTH COLL,HANOVER,NH 03755. USA,COLD REG RES & ENGN LAB,HANOVER,NH 03755. RP UNGAR, SG (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 7 TC 14 Z9 14 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18969 EP 18977 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000054 ER PT J AU WANG, JR GOGINENI, SP AMPE, J AF WANG, JR GOGINENI, SP AMPE, J TI ACTIVE AND PASSIVE MICROWAVE MEASUREMENTS OF SOIL-MOISTURE IN FIFE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SURFACE-ROUGHNESS; BACKSCATTER; VEGETATION; EMISSION; PRAIRIE AB During the intensive field campaigns of the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) in May-October of 1987, several nearly simultaneous measurements were made with low-altitude flights of the L-band radiometer and C- and X-band scatterometers over two transects in the Konza Prairie Natural Research Area, some 8 km south of Manhattan, Kansas. These measurements showed that although the scatterometers were sensitive to soil moisture variations in most regions under the flight path, the L-band radiometer lost most of its sensitivity in regions unburned for many years. The correlation coefficient derived from the regression between the radar backscattering coefficient and the soil moisture was found to improve with the increase in antenna incidence angle. This is attributed to a steeper falloff of the backscattering coefficient as a function of local incidence at angles near nadir than at angles greater than 30-degrees. Applying an initial slope correction to the measured data generally improves the correlation coefficient. At C band the improvement factor is found to be about 0.08 near vertical and gradually decreases to 0.04 at 45-degrees incidence angle. C1 UNIV KANSAS,RADAR SYST & REMOTE SENSING LAB,LAWRENCE,KS 66045. RP WANG, JR (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 25 TC 18 Z9 18 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 18979 EP 18985 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000055 ER PT J AU DAVIS, FW SCHIMEL, DS FRIEDL, MA MICHAELSEN, JC KITTEL, TGF DUBAYAH, R DOZIER, J AF DAVIS, FW SCHIMEL, DS FRIEDL, MA MICHAELSEN, JC KITTEL, TGF DUBAYAH, R DOZIER, J TI COVARIANCE OF BIOPHYSICAL DATA WITH DIGITAL TOPOGRAPHIC AND LAND-USE MAPS OVER THE FIFE SITE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TALLGRASS PRAIRIE; CLASSIFICATION; FIRE AB Sampling design is critical in locating ground sampling stations for large-scale climatological field experiments. In the stratified sampling design adopted for the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE), the study region was stratified into 14 different terrain units based on land use/land cover and topographic variables that were hypothesized to have a strong influence on surface biophysical properties. Digital terrain maps were produced to facilitate ground data integration and extrapolation. This paper describes the biophysical stratification of the FIFE site, implementation of the stratification using geographic information system (GIS) techniques, and validation of the stratification with respect to field measurements of biomass, soil moisture, Bowen ratio (beta), and the greenness vegetation index (GVI) derived from thematic mapper satellite data. Maps of burning and topographic position were significantly associated with variation in biomass, GVI, and beta. The effects of burning and topography were stronger for the Konza Prairie Long-Tem Ecological Research (KPLTER) site than for the rest of the FIFE site, where cattle grazing was a major confounding effect. The stratified design did not appreciably change the estimated site-wide means for surface climate parameters but accounted for between 25 and 45% of the sample variance depending on the variable. The design was weakened by undersampling of several strata, by high within-station variance in soil and vegetation data, and by failure to account for diverse land management practices on private lands surrounding KPLTER. We recommend that future large-scale climatological studies include the development of a digital terrain data base well in advance of field campaigns and that multitemporal imagery be used to obtain preliminary estimates of spatial and temporal variance in surface biophysical properties. We also recommend that sampling for the most heterogeneous biophysical variables be conducted in the framework of a multistage estimation scheme incorporating remotely sensed data. Although this means that ground-based estimation of regional fluxes cannot be made independent of aircraft or satellite data, it may well be the only means of obtaining reliable estimates of these variables over large areas. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. UNIV CALIF SANTA BARBARA,CTR REMOTE SENSING & ENVIRONM OPT,SANTA BARBARA,CA 93106. UNIV MARYLAND,DEPT GEOG,COLL PK,MD 20742. COLORADO STATE UNIV,NAT RESOURCE ECOL LAB,FT COLLINS,CO 80523. COLORADO STATE UNIV,COOPERAT INST RES ATMOSPHERE,FT COLLINS,CO 80523. RP DAVIS, FW (reprint author), UNIV CALIF SANTA BARBARA,DEPT GEOG,SANTA BARBARA,CA 93106, USA. RI Dozier, Jeff/B-7364-2009; Kittel, Timothy/F-2792-2011; Davis, Frank/B-7010-2009 OI Dozier, Jeff/0000-0001-8542-431X; Kittel, Timothy/0000-0002-4153-1006; Davis, Frank/0000-0002-4643-5718 NR 30 TC 24 Z9 25 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 19009 EP 19021 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000058 ER PT J AU SELLERS, PJ HEISER, MD HALL, FG AF SELLERS, PJ HEISER, MD HALL, FG TI RELATIONS BETWEEN SURFACE CONDUCTANCE AND SPECTRAL VEGETATION INDEXES AT INTERMEDIATE (100M2 TO 15KM2) LENGTH SCALES SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SIMPLE BIOSPHERE MODEL; CANOPY REFLECTANCE; AMAZONIAN FOREST; PHOTOSYNTHESIS; RADIATION; TRANSPIRATION AB The theoretical analysis of Sellers et al. (1992) indicates that the relative response of the unstressed canopy conductance (g(c)*) to changes in incident (nonsaturating) PAR flux (F0) should be proportional to some spectral vegetation indices (SVI), specifically the simple ratio (SR) vegetation index, for vegetation covers of similar physiology and physiognomy; or del(F) = (partial derivative g(c)*/partial derivative F0) is-proportional-to SR. This relationship was tested using the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) flux station data set (g(c)*) and the FIFE Landsat thematic mapper image data (SVI). The flux station data were used to invert a soil-plant-atmosphere model (the simple biosphere model (SiB) of Sellers et al., 1986) to derive estimates of g(c)* separate from the soil evaporation contribution and corrected for the "stress" effects of vapor pressure deficit and soil moisture deficit. The Landsat imagery was sampled to produce SR vegetation index values for small areas (90 x 90 m) centered on each flux station. The derived del(F) and SR values were found to be near-linearly related on a site-by-site basis. Differences between sites are thought to be related to the fractional cover Of C3 versus C4 vegetation so that del(S,F) = (partial derivative F/partial derivative(SR)) is-proportional-to V3, where V3 is the fractional cover Of C3 vegetation. The above equations form the basis for a simple biophysically based model of canopy-scale conductance. The model was applied on the flux station scale (100 m)2 and was also used to calculate fluxes for the entire FIFE site (15 x 15 km)2; the latter results were compared with airborne flux measurements. It is demonstrated that because the proposed relationship between del(F) and SR is near-linear, the calculation of evapotranspiration rates for large areas using this model is effectively scale-invariant. C1 UNIV MARYLAND, DEPT METEOROL, COLA, COLL PK, MD 20742 USA. RP SELLERS, PJ (reprint author), NASA, GODDARD SPACE FLIGHT CTR, GREENBELT, MD 20771 USA. NR 30 TC 158 Z9 164 U1 0 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 19033 EP 19059 PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000060 ER PT J AU HALL, FG HUEMMRICH, KF GOETZ, SJ SELLERS, PJ NICKESON, JE AF HALL, FG HUEMMRICH, KF GOETZ, SJ SELLERS, PJ NICKESON, JE TI SATELLITE REMOTE-SENSING OF SURFACE-ENERGY BALANCE - SUCCESS, FAILURES, AND UNRESOLVED ISSUES IN FIFE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID PHOTOSYNTHETICALLY ACTIVE RADIATION; CANOPY REFLECTANCE; STOMATAL CONDUCTANCE; MODEL; TRANSPIRATION; TEMPERATURE; ABSORPTION; SCATTERING; LEAVES; FIELD AB The FIFE staff science group, consisting of the authors, developed and evaluated process models relating surface energy and mass flux, that is, surface rates, to boundary layer and surface biophysical characteristics, that is, surface states. In addition, we developed and evaluated remote sensing algorithms for inferring surface state characteristics. In this paper we report the results of our efforts. We also look in detail at the sensor and satellite platform requirements (spatial resolution and orbital requirements) as driven by surface energy balance dynamics and spatial variability. We examine also the scale invariance of the process models and remote sensing algorithms, that is, to what degree do the remotely sensed parameters and energy balance relations translate from the patch level where they were developed to the mesoscale level where they are required? Finally, we examine the atmospheric correction and calibration issues involved in extending the remotely sensed observations within a season and between years. From these investigations we conclude that (1) existing formulations for the radiation balance and latent heat components of the surface energy balance equation are valid at the patch level. (2) Many of the surface physiological characteristics that parameterize these formulations can be estimated using satellite remote sensing at both local and regional scales; a few important ones cannot. (3) The mathematical structures relating radiation and surface energy flux to remote sensing parameters are, for the most part, scale invariant over the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) study area. The conditions for scale invariance are derived. (4) The precision of satellite remote sensing estimates of surface reflectance, calibrated and corrected for atmospheric effects, is no worse than about 1% absolute. The errors may actually be smaller, but an upper bound of 1% results from sampling variance caused by differences among the satellite and ground sensors in spatial resolution, atmospheric effects, and calibration. (5) Afternoon cumulus in the study area required both the Landsat and the SPOT satellites for monitoring of the vegetation dynamics. This result implies the need for multiple polar orbiters, or geosynchronous satellites in an operational implementation. We found that canopy Fpar, the fraction of incident photosynthetically active radiation absorbed by a canopy, can be estimated with an error of about 10% using remote sensing, provided that regional variability in the reflectance of the canopy substrate is dealt with properly. We also found that spectral vegetation indices (VIs) respond primarily to the photosynthetically active radiation absorbed by the live or green component of the canopy as opposed to its necrotic or dead vegetation. This is of critical importance since radiation absorption by the live part of the canopy is the rate-limiting process for photosynthesis and other key process rates such as evaporation. We found for the FIFE study area the surface moisture content at 0 to 10 cm to be another key rate-limiting variable in photosynthesis and evaporation. At gravimetric soil moisture levels below 20%, photosynthesis and evaporation were strongly attenuated. Only microwave sensors have shown potential for satellite remote sensing of soil moisture and only in the top few centimeters. Hydrological models may also play a critical role in monitoring root zone soil moisture levels, but additional research is needed. From our review of the research of others in FIFE we conclude that downwelling shortwave radiation and surface albedo are also amenable to remote sensing. Unfortunately, from our research we also found that the remote estimation of surface temperature to useful accuracies is problematical; consequently, the use of thermal infrared measurements to infer sensible heat flux is probably not feasible to acceptable accuracies. RP HALL, FG (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. RI Goetz, Scott/A-3393-2015 OI Goetz, Scott/0000-0002-6326-4308 NR 56 TC 298 Z9 312 U1 4 U2 47 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 19061 EP 19089 PG 29 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000061 ER PT J AU SELLERS, PJ HALL, FG AF SELLERS, PJ HALL, FG TI FIFE IN 1992 - RESULTS, SCIENTIFIC GAINS, AND FUTURE-RESEARCH DIRECTIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB The First ISLSCP Field Experiment (FIFE) is an international, land-surface-atmosphere experiment taking place at and around the Konza Prairie Long Term Ecological Research (LTER) site near Manhattan, Kansas. The objectives of FIFE are to better understand the role of biology in controlling the interactions between the atmosphere and the vegetated land surface and to investigate the use of satellite observations to infer climatologically significant land surface parameters. FIFE is necessarily an interdisciplinary, coordinated effort as these objectives require the cooperation of researchers working the fields of remote sensing, atmospheric physics, meteorology, and biology. RP SELLERS, PJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 51 TC 62 Z9 63 U1 2 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 30 PY 1992 VL 97 IS D17 BP 19091 EP 19109 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KC520 UT WOS:A1992KC52000062 ER PT J AU PARKINSON, CL AF PARKINSON, CL TI SOUTHERN-OCEAN SEA-ICE DISTRIBUTIONS AND EXTENTS SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES B-BIOLOGICAL SCIENCES LA English DT Article ID CARBON-DIOXIDE; VARIABILITY AB Southern Ocean sea-ice coverage undergoes a large seasonal cycle, with a nearly fivefold increase in areal ice extents from the minimum in February to the maximum in September, and significant interannual variations. Results presented here show in a variety of forms some of the variability that occurred in Southern Ocean sea-ice distributions and extents over the 1970s and 1980s. Interannual variability is examined by identifying changes in three measures: sea-ice extents, sea-ice distributions, and the length of the sea-ice season. Regarding these three: (i) Maximum ice extents varied by approximately 12%, decreasing during the mid-1970s, followed by increases over the next few years and a levelling off for much of the 1980s. (ii) The area of interannual variability in monthly average sea-ice distributions in summer far exceeds the summertime area of consistent ice coverage, in sharp contrast to the wintertime situation, when the area of consistent ice coverage is considerably larger. In winter, the ice-distribution variability is largely confined to two regions: a relatively narrow outer band (generally 2-5-degrees of latitude) surrounding the region of consistent ice coverage, and, for the mid-1970s, the region of an occasional large open water area within the ice pack of the Weddell Sea, termed the Weddell polynya. The Weddell and other polynyas within the ice cover allow intensified heat, mass, and momentum exchanges between ocean and atmosphere. thereby affecting regional oceanic and atmospheric circulations. (iii) The length of the sea-ice season, calculated for the years 1979-1986, with satellite passive-microwave data coverage through all months of the year, showed increases over that period in the Ross Sea but decreases in the Weddell and Bellingshausen seas. In both cases it appears, through comparisons with data from 1973 1976, that the 1979-1986 changes more likely reflect a fluctuating behaviour of the ice cover than a long-term trend. The changes in the ice cover have influences not only on the ocean and the atmosphere but on aquatic plant and animal life as well. RP PARKINSON, CL (reprint author), NASA,GODDARD SPACE FLIGHT CTR,OCEANS & ICE BRANCH,CODE 971,GREENBELT,MD 20771, USA. RI Parkinson, Claire/E-1747-2012 OI Parkinson, Claire/0000-0001-6730-4197 NR 22 TC 6 Z9 6 U1 0 U2 0 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON, ENGLAND SW1Y 5AG SN 0962-8436 J9 PHILOS T ROY SOC B JI Philos. Trans. R. Soc. Lond. Ser. B-Biol. Sci. PD NOV 30 PY 1992 VL 338 IS 1285 BP 243 EP 250 DI 10.1098/rstb.1992.0144 PG 8 WC Biology SC Life Sciences & Biomedicine - Other Topics GA KB198 UT WOS:A1992KB19800006 ER PT J AU TRAJMAR, S REGISTER, DF CARTWRIGHT, DC CSANAK, G AF TRAJMAR, S REGISTER, DF CARTWRIGHT, DC CSANAK, G TI DIFFERENTIAL AND INTEGRAL CROSS-SECTIONS FOR ELECTRON-IMPACT EXCITATION OF THE N(3)S, N(1)S AND N(3)P (N = 2, 3) LEVELS IN HE SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID INTERMEDIATE ENERGIES; INELASTIC-SCATTERING; GROUND-STATE; 23P STATES; HELIUM; ATOMS; THRESHOLD; N=2; POLARIZATION; COLLISION AB Differential and integral electron impact excitation cross sections are reported for the n3S, n1S and n3P (n = 2, 3) levels in He. Differential cross sections were measured at 30, 50 and 100 eV impact energies in the 10-degrees to 135-degrees angular range, extrapolated to 0 and 180-degrees, and then integrated over all angles to obtain integral cross sections at these three incident electron energies. In addition, differential cross sections were measured for excitation of the n3S (n = 2, 3, 4, 5), n1S and n3P (n = 2, 3, 4) levels at 60 eV impact energy and 30-degrees scattering angle. Theoretical cross sections based on first-order many-body theory (FOMBT) are also reported for these three final state symmetries for the 30-500 eV impact energy range. These new experimental and theoretical results are compared with other data. In general, good qualitative agreement is found between the experimental and theoretical results but there are quantitative discrepancies in the absolute values obtained by experiment and various theoretical methods at impact energies less than 100 eV. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP TRAJMAR, S (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 59 TC 51 Z9 51 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD NOV 28 PY 1992 VL 25 IS 22 BP 4889 EP 4910 DI 10.1088/0953-4075/25/22/022 PG 22 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA KA750 UT WOS:A1992KA75000022 ER PT J AU LACIS, AA CARLSON, BE AF LACIS, AA CARLSON, BE TI GLOBAL WARMING - KEEPING THE SUN IN PROPORTION SO NATURE LA English DT Editorial Material RP LACIS, AA (reprint author), GODDARD INST SPACE STUDIES,2880 BROADWAY,NEW YORK,NY 10025, USA. RI Lacis, Andrew/D-4658-2012; Carlson, Barbara/D-8319-2012 NR 7 TC 4 Z9 4 U1 1 U2 3 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD NOV 26 PY 1992 VL 360 IS 6402 BP 297 EP 297 DI 10.1038/360297a0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JZ630 UT WOS:A1992JZ63000027 ER PT J AU MAHAJAN, AJ STEWART, RB AF MAHAJAN, AJ STEWART, RB TI THE PREDICTION OF THERMODYNAMIC PROPERTIES OF THE LIQUID - VAPOR COEXISTENCE STATES SO FLUID PHASE EQUILIBRIA LA English DT Article DE PREDICTION OF VAPOR PRESSURE; SATURATED LIQUID DENSITY; LIQUID-VAPOR COEXISTENCE PROPERTIES ID CORRESPONDING STATES; TRIPLE POINT; DENSITIES; PRESSURES; CURVE AB A new predictive method for estimation of accurate thermodynamic properties of the liquid-vapor coexistence states is presented. The new method is based on the predictive methods by Pitzer, Lee and Kesler, and Armstrong and Teja. Calculated values of vapor pressure and saturated liquid density for argon, nitrogen, ethylene, oxygen, fluorine, methane, dichlorodifluoromethane (R12) and propane are used to demonstrate the method. The requirements of a new predictive method are given including the criteria for the selection of the two reference fluids used. The accuracy of the predictions depends primarily on the accuracy of the thermodynamic property formulations for the two reference fluids. The results of the calculations used in demonstrating the method show that vapor pressures and saturated liquid densities may be predicted within +/- 0.05 percent with the available equations for the test fluids. C1 UNIV TOLEDO,CLEVELAND,OH 44135. NASA,LEWIS RES CTR,CTR APPL THERMODYNAM STUDIES,CLEVELAND,OH 44135. NR 21 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD NOV 25 PY 1992 VL 79 BP 63 EP 75 DI 10.1016/0378-3812(92)85120-W PG 13 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA KC395 UT WOS:A1992KC39500006 ER PT J AU OSTRO, SJ CAMPBELL, DB SIMPSON, RA HUDSON, RS CHANDLER, JF ROSEMA, KD SHAPIRO, II STANDISH, EM WINKLER, R YEOMANS, DK VELEZ, R GOLDSTEIN, RM AF OSTRO, SJ CAMPBELL, DB SIMPSON, RA HUDSON, RS CHANDLER, JF ROSEMA, KD SHAPIRO, II STANDISH, EM WINKLER, R YEOMANS, DK VELEZ, R GOLDSTEIN, RM TI EUROPA, GANYMEDE, AND CALLISTO - NEW RADAR RESULTS FROM ARECIBO AND GOLDSTONE SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID COHERENT BACKSCATTERING; SATELLITES; LIGHT; REFLECTIVITY; MEDIA; LOCALIZATION; EPHEMERIDES; SCATTERING; ECHOES; TITAN AB Observations of the icy Galilean satellites, conducted during 1987-1991 with the Arecibo 13-cm system and the Goldstone 3.5-an system, yield significant improvements in our knowledge of the satellites' radar properties. Hardly any wavelength dependence is seen for either the total power radar albedo sigma(T) or the circular polarization ratio mu(C). For Europa, Ganymede, and Callisto our 13-cm estimates of mean values and rms dispersions are sigma(T) = 2.60 +/- 0.22, 1.39 +/- 0.14, and 0.69 +/- 0.06; and mu(C) = 1.53 +/- 0.03, 1.43 +/- 0.06, and 1.17 +/- 0.04. Radar albedo features am seen on each satellite. Evidence for mu(C) features is lacking, except for indications of a weak hemispheric asymmetry for Callisto. That intersatellite and intrasatellite fractional variations in albedo greatly exceed variations in mu(C) is consistent with predictions of coherent backscatter theory and implies that albedo might be a crude indicator of relative silicate abundance. The satellites' albedo distributions overlap. The most prominent radar features are tentatively identified with Galileo Regio and the Valhalla basin. Estimates of echo Doppler frequencies show Callisto to be lagging its ephemeris by 200 +/- 50 km. C1 JET PROP LAB,PASADENA,CA 91109. CORNELL UNIV,NATL ASTRON & IONOSPHERE CTR,ITHACA,NY 14853. STANFORD UNIV,CTR RADAR ASTRON,STANFORD,CA 94305. HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138. WASHINGTON STATE UNIV,SCH ELECT ENGN & COMP SCI,PULLMAN,WA 99164. NATL ASTRON & IONOSPHERE CTR,ARECIBO,PR 00613. NR 35 TC 64 Z9 64 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD NOV 25 PY 1992 VL 97 IS E11 BP 18227 EP 18244 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KU056 UT WOS:A1992KU05600001 ER PT J AU ZUBER, MT MOUGINISMARK, PJ AF ZUBER, MT MOUGINISMARK, PJ TI CALDERA SUBSIDENCE AND MAGMA CHAMBER DEPTH OF THE OLYMPUS MONS VOLCANO, MARS SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID KILAUEA-VOLCANO; HAWAII; DEFORMATION; MECHANICS; RIFT; LITHOSPHERE; TOPOGRAPHY; RESERVOIRS; TECTONICS; ERUPTION AB Observations of the distribution of tectonic features and their relationship to local surface topography indicate that the floor of the oldest and largest crater of the summit caldera of Mars' Olympus Mons volcano may have undergone subsidence in response to depressurization of a subsurface magma chamber. In this study, we construct an axisymmetric finite element model to calculate elastic stresses in a volcanic edifice to investigate the relationship between surface tectonism, caldera subsidence, and the physical characteristics of Olympus Mons' magmatic reservoir. Constraints on the model are provided by the stress field within the crater indicated by the distribution of radial ridges and circumferential graben that we hypothesize formed due to a postcollapse and postresurfacing phase of subsidence of the caldera floor. Model results show that the surface stress state is not strongly sensitive to the aspect ratio or pressure distribution of the magma chamber, or to the contrast in stiffness between the magma chamber and surroundings, but is strongly dependent on the width and depth of the chamber. For a range of plausible model parameters, we find the maximum depth to the top of the magma chamber to have been less-than-or-equal-to 16 km, which indicates that the chamber, at the time of crater floor subsidence, was positioned within the Olympus Mons edifice, at a level much shallower than the estimated source depth of Martian magmas (approximately 140-200 km). The allowable range of solutions indicates that the vertical position of the magma chamber may have been controlled by the neutral buoyancy level of ascending magma. Our results suggest a gross similarity between the configurations of the magmatic plumbing systems of Olympus Mons and several well-studied terrestrial volcanoes such as the Hawaiian shields. C1 NASA,GODDARD SPACE FLIGHT CTR,GEODYNAM BRANCH,GREENBELT,MD 20771. UNIV HAWAII,SCH OCEAN & EARTH SCI & TECHNOL,DEPT GEOL & GEOPHYS,HONOLULU,HI 96822. NR 68 TC 34 Z9 34 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD NOV 25 PY 1992 VL 97 IS E11 BP 18295 EP 18307 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KU056 UT WOS:A1992KU05600007 ER PT J AU FROST, SJ CHEN, YM WHITSON, PA AF FROST, SJ CHEN, YM WHITSON, PA TI ATRIAL-NATRIURETIC-PEPTIDE DEGRADATION BY CPA47 CELLS - EVIDENCE FOR A DIVALENT CATION-INDEPENDENT CELL-SURFACE PROTEOLYTIC ACTIVITY SO BIOCHIMICA ET BIOPHYSICA ACTA LA English DT Article DE ATRIAL NATRIURETIC PEPTIDE; ANP; DEGRADATION; CPA47-CELL; ENDOTHELIAL CELL; HPLC ID RECEPTOR-MEDIATED ENDOCYTOSIS; COOH-TERMINAL TRIPEPTIDE; ENDOTHELIAL-CELLS; CLEARANCE FUNCTION; C RECEPTORS; ENDOPEPTIDASE-24.11; RAT; KALLIKREIN; HYDROLYSIS; METABOLISM AB Atrial natriuretic peptide (ANP) is rapidly cleared and degraded in vivo. Nonguanylate-cyclase receptors (C-ANPR) and a metalloproteinase, neutral endopeptidase (EC 3.4.24.11) (NEP 24.11), are thought to be responsible for its metabolism. We investigated the mechanisms of ANP degradation by an endothelial-derived cell line, CPA47. CPA47 cells degraded 88% of I-125-ANP after 1 h at 37-degrees-C as determined by HPLC. Medium preconditioned by these cells degraded 41 % of the I-125-ANP, and this activity was inhibited by a divalent cation chelator, EDTA. Furthermore, a cell-surface proteolytic activity degraded I-125-ANP in the presence of EDTA when receptor-mediated endocytosis was inhibited either by low temperature (4-degrees-C) or by hyperosmolarity at 37-degrees-C. The metalloproteinase, NEP 24.11, is unlikely to be the cell-surface peptidase because I-125-ANP is degraded by CPA47 cells at 4-degrees-C in the presence of 5 mM EDTA. These data indicate that CPA47 cells can degrade ANP by a novel divalent cation-independent cell-surface proteolytic activity. C1 NASA,LYNDON B JOHNSON SPACE CTR,BIOMED OPERAT & RES BRANCH,MAIL CODE SD4,HOUSTON,TX 77058. KRUG LIFE SCI INC,HOUSTON,TX. NR 29 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0006-3002 J9 BIOCHIM BIOPHYS ACTA PD NOV 23 PY 1992 VL 1112 IS 1 BP 45 EP 51 DI 10.1016/0005-2736(92)90252-H PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA JZ899 UT WOS:A1992JZ89900008 PM 1420268 ER PT J AU MIYOSHI, K WU, RLC GARSCADDEN, A AF MIYOSHI, K WU, RLC GARSCADDEN, A TI FRICTION AND WEAR OF DIAMOND AND DIAMOND-LIKE CARBON COATINGS SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 19TH INTERNATIONAL CONF ON METALLURGICAL COATINGS AND THIN FILMS CY APR 06-10, 1992 CL SAN DIEGO, CA ID TRIBOLOGICAL PROPERTIES; HYDROGENATED CARBON; FILMS; DEPOSITION AB Reciprocating sliding friction experiments were conducted with a natural diamond flat, diamond films, and low- and high-density diamondlike carbon (DLC) films in contact with pin specimens of natural diamond and silicon nitride (Si3N4) both in humid air and in dry nitrogen. The results indicated that for natural diamond pin contacts the diamond films and the natural diamond flat were not susceptible to moisture but that moisture could increase both the coefficients of friction and wear factors of the DLC films. The coefficients of friction and wear factors of the diamond films were generally similar to those of the natural diamond flat both in humid air and in dry nitrogen. In dry nitrogen the coefficients of friction of the high-density DLC films in contact with pin specimens of both diamond and Si3N4 were generally low (about 0.02) and similar to those of the natural diamond flat and the diamond films. The wear factors of the materials in contact with both natural diamond and Si3N4 were generally in the ascending order of natural diamond flat, diamond film, high-density DLC film, and low-density DLC film. Moisture in the environment increased the coefficients of friction for Si3N4 pins in contact with all the materials (natural diamond flat, diamond films, and DLC films). This increase in friction is due to the silicon oxides film produced on the surface of Si3N, pins in humid air. C1 UES INC,DAYTON,OH 45432. WRIGHT LAB,DAYTON,OH 45433. RP MIYOSHI, K (reprint author), NASA,LEWIS RES CTR,CLEVELAND,OH 44135, USA. NR 24 TC 101 Z9 101 U1 1 U2 6 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV 23 PY 1992 VL 55 IS 1-3 BP 428 EP 434 DI 10.1016/S0257-8972(07)80061-2 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA KA639 UT WOS:A1992KA63900015 ER PT J AU WU, RLC MIYOSHI, K VUPPULADHADIUM, R JACKSON, HE AF WU, RLC MIYOSHI, K VUPPULADHADIUM, R JACKSON, HE TI PHYSICAL AND TRIBOLOGICAL PROPERTIES OF RAPID THERMAL ANNEALED DIAMOND-LIKE CARBON-FILMS SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 19TH INTERNATIONAL CONF ON METALLURGICAL COATINGS AND THIN FILMS CY APR 06-10, 1992 CL SAN DIEGO, CA ID RAMAN SPECTRUM AB This paper reports the physical characterization and tribological properties of diamond-like carbon (DLC) and rapid thermal annealed (RTA) DLC films. Amorphous DLC films were deposited by the direct ion beam deposition technique using methane ions. Rapid thermal annealing (RTA) of the films was performed at several fixed temperatures (350, 400, 500, 600, 700, 800, 900 and 1000-degrees-C) in a nitrogen atmosphere for 2 min. The films were then characterized by proton recoil detection analysis for hydrogen content, Rutherford backscattering for carbon content and Raman spectroscopy for structural change. The hydrogen content of the DLC films remains constant at 30 at.% in the RTA temperature range 25-500-degrees-C, decreases rapidly from 25% to 9% in the range 600-800-degrees-C and finally remains at 5% in the range 900-1000-degrees-C. The Raman spectra of the DLC films do not change in the RTA temperature range 25-400-degrees-C and begin to show the appearance of crystalline graphitic carbon above 500-degrees-C. The coefficients of friction of the DLC films do not change significantly with the RTA process; however, the wear factors are strongly dependent on the annealing temperature and the moisture in the environment. C1 NASA,LEWIS RES CTR,CLEVELAND,OH 44135. UNIV CINCINNATI,DEPT PHYS,CINCINNATI,OH 45221. RP WU, RLC (reprint author), UES INC,4401 DAYTON XENIA RD,DAYTON,OH 45432, USA. RI Jackson, Howard/K-4881-2012 NR 17 TC 37 Z9 37 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV 23 PY 1992 VL 55 IS 1-3 BP 576 EP 580 DI 10.1016/S0257-8972(07)80085-5 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA KA639 UT WOS:A1992KA63900039 ER PT J AU RINSLAND, CP GOLDMAN, A AF RINSLAND, CP GOLDMAN, A TI INFRARED SPECTROSCOPIC MEASUREMENTS OF TROPOSPHERIC TRACE GASES SO APPLIED OPTICS LA English DT Note ID SOLAR ABSORPTION-SPECTRA; UNITED-STATES; CM-1; SO2 AB Absorption features of several trace gases have been detected in 0.017-cm-1-resolution infrared spectra recorded over surface-level paths of 0.5 and 1.5 km at the National Solar Observatory on Kitt Peak, near Tucson, Arizona. Measurements of O3, HCOOH, NH3, and H2CO are briefly discussed. C1 UNIV DENVER,DEPT PHYS,DENVER,CO 80208. RP RINSLAND, CP (reprint author), NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,HAMPTON,VA 23681, USA. NR 20 TC 18 Z9 18 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD NOV 20 PY 1992 VL 31 IS 33 BP 6969 EP 6971 PG 3 WC Optics SC Optics GA JY577 UT WOS:A1992JY57700005 PM 20802552 ER PT J AU DONE, C MADEJSKI, GM MUSHOTZKY, RF TURNER, TJ KOYAMA, K KUNIEDA, H AF DONE, C MADEJSKI, GM MUSHOTZKY, RF TURNER, TJ KOYAMA, K KUNIEDA, H TI THE X-RAY VARIABILITY OF NGC-6814 - POWER SPECTRUM SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, ACTIVE; GALAXIES, INDIVIDUAL (NGC 6814); METHODS, DATA ANALYSIS; X-RAYS, GALAXIES ID ACTIVE GALACTIC NUCLEI; QUASI-PERIODIC OSCILLATIONS; ELECTRON-POSITRON PAIRS; THICK ACCRETION DISKS; NON-THERMAL SOURCES; COLD MATTER; BLACK-HOLES; SPACED DATA; INSTABILITIES; REFLECTION AB NGC 6814 is unique among Seyfert galaxies in showing strong evidence for periodic X-ray behavior, first detected from an EXOSAT "long-look observation." Here simulation techniques are used to obtain the X-ray variability power spectrum of the unevenly sampled Ginga light curve of the object. A simple power law is not an adequate description of the power spectrum, with the residuals showing excess power on time scales consistent with the periodicity of 12,100 +/- 100 s seen in the EXOSAT data. Over 75% of the total source variability is due to the periodic component (rms amplitude of 36%). The residual variability can be described as the more usual " flicker noise " f-1.1 power law. This continues unbroken to time scales shorter than 300 s, so that the region from which the variability arises must be smaller than 10(13) cm. Folding techniques, combined with the simulations to obtain the error, give the period as 12,132 +/- 3 s. While the period is consistent with that seen in the EXOSAT data, the shape of the folded light curve is very different. There are three main peaks, two of which are separated by an extremely sharp dip, instead of the single peak and small harmonic structure observed by EXOSAT. Using the dip as a fiducial mark, a second Ginga observation of the source taken 1 year later is found to be consistent with being completely periodic and phase-coherent with the first Ginga observation. Thus the period is consistent with being constant over a time span of 6 years, but phase coherence is only maintained on time scales of less-than-or-equal-to 1 year. Subtle differences in the shape of the folded light curve with energy, and the very large amount of power in the periodic component, suggest occultation as its origin, although amplification of variability from an X-ray-emitting "hot spot" through gravitational lensing is also possible. The former suffers from the very arbitrary nature of the periodic time scale, while the latter is unattractive because it is difficult to trivially produce the different shape of the folded light curve seen in the Ginga and EXOSAT data. That both these models probably fail to provide an adequate explanation may be due to the added complexity of anisotropic X-ray emission, suggested by the discrepancy between the lack of soft photons implied by the flat spectrum and the copious source of soft photons available from reprocessing in the iron-line-producing material. C1 NASA,GODDARD SPACE FLIGHT CTR,LHEA,GREENBELT,MD 20771. NAGOYA UNIV,DEPT ASTROPHYS,CHIKUSA KU,NAGOYA,AICHI 464,JAPAN. RI done, chris/D-4605-2016 OI done, chris/0000-0002-1065-7239 NR 47 TC 77 Z9 77 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1992 VL 400 IS 1 BP 138 EP 152 DI 10.1086/171979 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX147 UT WOS:A1992JX14700012 ER PT J AU CHODOROWSKI, MJ ZDZIARSKI, AA SIKORA, M AF CHODOROWSKI, MJ ZDZIARSKI, AA SIKORA, M TI REACTION-RATE AND ENERGY-LOSS RATE FOR PHOTOPAIR PRODUCTION BY RELATIVISTIC NUCLEI SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMIC RAYS; NUCLEAR REACTIONS, NUCLEOSYNTHESIS, ABUNDANCES; RADIATION MECHANISM, MISCELLANEOUS ID ACTIVE GALACTIC NUCLEI; ORIGIN; INJECTION; EMISSION; NEUTRONS; PROTONS; RAYS AB We consider the process of e+/- pair production by relativistic nuclei (with Lorentz factors gamma much-greater-than 1) on ambient photons. The process is important for cosmic-ray nuclei in interstellar and intergalactic space as well as in galactic and extragalactic compact objects. The rate of this process is given by an integral of the cross section over the photon angular and energy distribution. In the case of isotropic photons, we perform the angular integration, providing an expression for the rate at given photon energy in the nucleus rest frame. The total rate becomes then a single integral of that rate over the photon energy distribution. We also give formulae for the fractional energy loss (the inelasticity coefficient) of a relativistic nucleus colliding with a photon of a given energy in the rest frame. The total nucleus energy-loss rate due to the process is then given by an integral of the inelasticity coefficient over the photon angular and energy distribution. We obtain the exact asymptotic form of the inelasticity coefficient at high photon energies and give a fit valid at lower energies. Finally, we integrate the nucleus energy-loss rate over the photon angular distribution in the case of isotropic photons and provide simple fits. This extends a result of Blumenthal, who obtained the asymptotic formula in the limit of very high photon energies. C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. MIT,CAMBRIDGE,MA 02139. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP CHODOROWSKI, MJ (reprint author), N COPERNICOS ASTRON CTR,BARTYCKA 18,PL-00716 WARSAW,POLAND. NR 42 TC 92 Z9 92 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1992 VL 400 IS 1 BP 181 EP 185 DI 10.1086/171984 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX147 UT WOS:A1992JX14700017 ER PT J AU SELLGREN, K WERNER, MW DINERSTEIN, HL AF SELLGREN, K WERNER, MW DINERSTEIN, HL TI SCATTERING OF INFRARED RADIATION BY DUST IN NGC-7023 AND NGC-2023 SO ASTROPHYSICAL JOURNAL LA English DT Article DE DUST, EXTINCTION; INFRARED, INTERSTELLAR, CONTINUUM; ISM, INDIVIDUAL (NGC-2023, NGC-7023); POLARIZATION; REFLECTION NEBULAE ID EXTENDED RED EMISSION; REFLECTION NEBULA NGC-2023; MOLECULAR-HYDROGEN EMISSION; CARBONACEOUS COMPOSITE QCC; INTER-STELLAR DUST; ORION NEBULA; SUBMILLIMETER POLARIZATION; PHOTODISSOCIATION REGION; INTERSTELLAR GRAINS; SURFACE BRIGHTNESS AB Linear polarization measurements at 1.25, 1.65, and 2.2 mum of the visual reflection nebulae NGC 7023 and NGC 2023 have been made to determine the contribution of scattered light to the total nebular emission. The percentage polarization of NGC 7023 slowly increases from 0.3 to 1 mum, with peak polarizations of up to 26% at 1.25 mum, then rapidly decreases, with values of 4%-7% at 2.2 mum. We interpret this as implying that scattered starlight contributes most to the short-wavelength emission, while unpolarized emission from small grains or large molecules dominates at longer wavelengths. Infrared polarization and surface brightness measurements are combined to derive the intensity of scattered light, which is then compared with scattering models. While the near-infrared emission of both NGC 2023 and NGC 7023 is dominated by small-grain or large-molecule emission, infrared scattered light plays a larger role in NGC 2023 than in NGC 7023. The near-infrared percentage polarization of NGC 2023 is comparable to the visual percentage polarization, but the polarization position angle appears to rotate with wavelength. The observations are consistent with polarization by scattering of starlight from two distinct sources, HD 37903 and star C, with the position-angle rotation caused by the increasing brightness of star C at longer wavelengths. This picture is supported by previous observations at 0.9 mum showing a small reflection nebula around star C. C1 NASA,AMES RES CTR,DIV SPACE SCI,MOFFETT FIELD,CA 94035. JET PROP LAB,PASADENA,CA 91109. UNIV TEXAS,DEPT ASTRON,AUSTIN,TX 78712. RP SELLGREN, K (reprint author), OHIO STATE UNIV,DEPT ASTRON,COLUMBUS,OH 43210, USA. NR 88 TC 47 Z9 47 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1992 VL 400 IS 1 BP 238 EP 247 DI 10.1086/171990 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX147 UT WOS:A1992JX14700023 ER PT J AU MORIARTYSCHIEVEN, GH WANNIER, PG TAMURA, M KEENE, J AF MORIARTYSCHIEVEN, GH WANNIER, PG TAMURA, M KEENE, J TI CIRCUMPROTOSTELLAR ENVIRONMENTS .1. MOLECULAR OUTFLOWS FROM PROTOSTAR CANDIDATES IN TAURUS SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM, JETS AND OUTFLOWS; STARS, PRE-MAIN-SEQUENCE ID HERBIG-HARO OBJECTS; YOUNG STARS; CO; CLOUDS; CORES; GAS AB We report on the search for molecular outflows from a complete, flux-limited, IRAS-selected sample of cold, low-mass protostar candidates located in the Taurus cloud complex. We find that 18 of the 24 sources have outflows associated with them, only four of which have been previously reported, implying that these sources are predominantly protostars in an early stage of evolution. We argue that at least a few of the outflows are very small in extent, indicating that their dynamical ages are less than a few thousand years. C1 CALTECH,PASADENA,CA 91125. JET PROP LAB,PASADENA,CA 91109. NR 15 TC 59 Z9 59 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1992 VL 400 IS 1 BP 260 EP 264 DI 10.1086/171992 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX147 UT WOS:A1992JX14700025 ER PT J AU SMALE, AP MUKAI, K WILLIAMS, OR JONES, MH CORBET, RHD AF SMALE, AP MUKAI, K WILLIAMS, OR JONES, MH CORBET, RHD TI GINGA OBSERVATIONS OF THE DIPPING LOW-MASS X-RAY BINARIES XB 1916-053 AND EXO 0748-676 SO ASTROPHYSICAL JOURNAL LA English DT Article DE BINARIES, ECLIPSING; STARS, INDIVIDUAL (XB 1916-053, EXO 0748-676); X-RAYS, STARS ID LARGE AREA COUNTERS; ACCRETION DISK RIM; BURST PROPERTIES; BEHAVIOR; SENSITIVITY; X-1822-371; DISCOVERY; ORIGIN AB Several low-mass X-ray binaries display pronounced dips of variable depth and duration in their X-ray light curves, due to the periodic occultation of the central source by azimuthal accretion disk structure. We present results from Ginga observations of two such sources, XB 1916-053 and EXO 0748-676. XB 1916-053 was observed for 3 days in 1988 September. Periodicity studies show results consistent with those from previous Ginga observations (Smale et al. 1989), specifically that the derived X-ray period is shorter than the optical period by approximately 1 %. We discuss this problem in detail, drawing from current knowledge on CVs as well as LMXBs, and describe a more refined model for the system. If the accretion disk in XB 1916-053 is elliptical, the azimuthal position of the structure remains fixed in the binary reference frame, and thus the primary X-ray dips recur at the orbital period. However, the vertical extent of the disk structure, and thus the reprocessed optical emission, will be modulated on the beat between the orbital and disk precession periods, producing the observed period discrepancy. Three bursts were detected during the observation of XB 1916-053, the second of which occurred during a dip. Spectral analysis suggests that the second burst caused an almost instantaneous ionization of the absorbing medium in the line of sight; this material then returned to its equilibrium state on the same time scale as the burst decay. We show that the theoretical ionization and recombination time scales are short enough for this to be feasible, and that the total burst fluence is large enough to produce such an effect. In addition, we find evidence that the bursts cause a approximately threefold increase in the emission component from the disk. We observed EXO 0748 - 676 in 1989 March, also for 3 days. The source was found to be in a bright state, and data were obtained covering two eclipses and many dips. We have analyzed intensity-selected spectra accumulated from the dipping intervals of both XB 1916-053 and EXO 0748-676, and in addition have performed simulations to assess the effects of a rapidly changing column density upon the observed spectra from these sources. We show that during dipping intervals, where N(H) varies on a time scale shorter than the spectral integration time, spectral mixing can produce an apparent low-energy component in the data. Thus, rapidly variable simple absorption is indistinguishable from partial covering. From the variability analysis, we place loose limits upon the possible clumpiness of the material responsible for the accretion disk structure in XB 1916 - 053 and EXO 0748 - 676. C1 UNIV CALIF BERKELEY,CTR EUV ASTROPHYS,BERKELEY,CA 94720. QUEEN MARY & WESTFIELD COLL,SCH MATH SCI,ASTRON UNIT,LONDON E1 4NS,ENGLAND. PENN STATE UNIV,DEPT ASTRON & ASTROPHYS,UNIV PK,PA 16802. EUROPEAN SPACE TECHNOL CTR,DIV ASTROPHYS,2200 AG NOORDWIJK,NETHERLANDS. RP SMALE, AP (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,CODE 666,GREENBELT,MD 20771, USA. NR 31 TC 35 Z9 35 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1992 VL 400 IS 1 BP 330 EP 343 DI 10.1086/171999 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX147 UT WOS:A1992JX14700032 ER PT J AU HUTCHINGS, JB BIANCHI, L LAMERS, HJGLM MASSEY, P MORRIS, SC AF HUTCHINGS, JB BIANCHI, L LAMERS, HJGLM MASSEY, P MORRIS, SC TI HUBBLE-SPACE-TELESCOPE SPECTROSCOPY OF OB STARS IN M31 SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, INDIVIDUAL, M31; ISM, DUST, EXTINCTION; STARS, MASS LOSS ID WOLF-RAYET STARS; STELLAR WINDS; LINE-PROFILES; SEI METHOD; MASS-LOSS AB We have obtained UV spectra of two luminous hot stars in M31 with the Hubble Space Telescope. The stars are of late O and WN spectral type and lie on opposite sides of M31. We derive UV extinction curves for M31 which differ from both the Galaxy and the LMC. We find differences between the IS absorbers in both lines of sight in M31 and in the Galactic halo, 77" apart. The stellar wind-driven mass loss of the stars is found to be 10 times lower than in similar Galactic stars. One star appears to be an eclipsing W-R binary. C1 OSSERV ASTRON TORINO,I-10025 PINO TORINESE,ITALY. SPACE RES LAB,3584 CA UTRECHT,NETHERLANDS. NASA,ESA,WASHINGTON,DC 20546. KITT PEAK NATL OBSERV,TUCSON,AZ 85726. RP HUTCHINGS, JB (reprint author), NATL RES COUNCIL CANADA,DOMINION ASTROPHYS OBSERV,5071 W SAANICH RD,VICTORIA V8X 4M6,BC,CANADA. NR 18 TC 21 Z9 21 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1992 VL 400 IS 1 BP L35 EP L38 DI 10.1086/186643 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX148 UT WOS:A1992JX14800010 ER PT J AU WASILEWSKI, PJ MAYHEW, MA AF WASILEWSKI, PJ MAYHEW, MA TI THE MOHO AS A MAGNETIC BOUNDARY REVISITED SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LOWER CONTINENTAL-CRUST; REMANENT MAGNETIZATION; MANTLE BOUNDARY; ANOMALIES; ROCKS; LITHOSPHERE; MINERALOGY; CONTRIBUTE; XENOLITHS; EVOLUTION AB We have re-examined the question of whether it is generally true that in continental regions a relatively magnetic crust overlies a relatively non-magnetic mantle. Whereas the original conclusion was based on limited data, the present study is based on about 400 globally-distributed xenolith samples. While it is now clear that the "Moho" represents a maximum velocity gradient in a complex transition from crust to mantle, and while crustal magnetization is highly variable, the original concept of a "magnetic crust" overlying a non-magnetic mantle is strongly supported by the new data. A large upper mantle xenolith suite of ultramafic composition is characterized by non-magnetic chrome spinels and magnesian ilmenites. Such rocks are magnetic only where demonstrably altered. The most significantly magnetic rocks within the crust are mafic types prograded to granulite grade or mafic melts of basaltic composition which crystallized deep in the crust at high pressure and temperature. Prograded rocks have characteristic magnetite Curie points, and are strongly magnetic, especially the more mafic compositions, while the mafic rocks formed by crystallization at depth have Curie points between 400-degrees-570-degrees-C and are strongly magnetic. Induced magnetizations are commonly several A/m, and can readily account for long-wavelength magnetic anomalies measured by satellite and aircraft; thus, there is no need to search for exotic sources for "missing" crustal magnetization. No metal or other peculiar magnetic species have been observed by us in any of our (unaltered) samples. Mineral assemblages (including magnetic components) are consistent with oxidizing conditions close to the FMQ buffer. C1 NATL SCI FDN,WASHINGTON,DC 20550. RP WASILEWSKI, PJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 33 TC 74 Z9 78 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD NOV 20 PY 1992 VL 19 IS 22 BP 2259 EP 2262 DI 10.1029/92GL01997 PG 4 WC Geosciences, Multidisciplinary SC Geology GA KA015 UT WOS:A1992KA01500019 ER PT J AU RYAN, WF DICKERSON, RR HUFFMAN, GJ LUKE, WT AF RYAN, WF DICKERSON, RR HUFFMAN, GJ LUKE, WT TI TROPOSPHERIC CHEMISTRY OVER THE LOWER GREAT-PLAINS OF THE UNITED-STATES .1. METEOROLOGY SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review ID MESOSCALE CONVECTIVE COMPLEXES; ATMOSPHERIC TRACE GASES; OZONE PRODUCTION; BOUNDARY-LAYER; VERTICAL-DISTRIBUTION; SYNOPTIC CLIMATOLOGY; FRONTAL SURFACES; OKLAHOMA DRYLINE; CLOUD TRANSPORT; WEATHER SYSTEMS AB Convective clouds and thunderstorms inject planetary boundary layer air with high concentrations of ozone (03) and 03 Precursors into the free troposphere. By altering the chemistry and radiative balance of the upper troposphere, these local actions can have global consequences. In order to extrapolate from individual observations to general trends we have devised a method to identify weather patterns conducive to convection in the southern or lower Great Plains in early summer and applied this method to meteorological and chemical data from a series of research flights carried out in June 1985. Previous studies have noted that weather patterns in the lower Great Plains in this season are characterized by alternating pulses of polar and maritime air masses and very frequent episodes of violent convection, usually in maritime conditions in advance of a surface cold front or along the frontal zone itself. In this study, a set of selection criteria is applied to surface and upper air meteorological data from central Oklahoma to distinguish the two meridional phases characteristic of this region: maritime and polar. A deep layer of moist, southerly flow and convective instability is encountered in the maritime regime, while the polar phase is convectively stable throughout the midtroposhere and much less conducive to convection. For the period 1980-1985 both maritime and polar regimes occur with a frequency of about 35% in May, while the maritime phase becomes dominant in June (53% maritime versus 20% polar). Within the maritime regime, conditions conducive to the development of severe storms are characterized by the presence of a dry, low-level inversion that tends to inhibit scattered midday convection over a wide region while simultaneously enhancing the probability of larger thunderstorms and mesoscale convective systems. This "modified maritime" category accounts for approximately 25% of the total cases in May and in June. The instances of frontal passage account for approximately 15% of the total cases. Profiles, from the surface to 200 mbar, made on 18 flights of the NCAR Sabreliner in the 1985 PRESTORM project, am categorized according to the selection criteria. Part 2 of this study presents representative concentrations of ozone, carbon monoxide, and reactive nitrogen compounds as a function of altitude (0-12 km) for each category and discusses the implications of these findings. C1 NASA,GODDARD SPACE FLIGHT CTR,UNIV SPACE RES ASSOCIATES,GREENBELT,MD 20771. UNIV MARYLAND,DEPT CHEM,COLL PK,MD 20742. RP RYAN, WF (reprint author), UNIV MARYLAND,DEPT METEOROL,COLL PK,MD 20742, USA. RI Huffman, George/F-4494-2014; Luke, Winston/D-1594-2016; Dickerson, Russell/F-2857-2010 OI Huffman, George/0000-0003-3858-8308; Luke, Winston/0000-0002-1993-2241; Dickerson, Russell/0000-0003-0206-3083 NR 108 TC 8 Z9 8 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1992 VL 97 IS D16 BP 17963 EP 17984 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA JZ602 UT WOS:A1992JZ60200001 ER PT J AU PICKERING, KE THOMPSON, AM SCALA, JR TAO, WK DICKERSON, RR SIMPSON, J AF PICKERING, KE THOMPSON, AM SCALA, JR TAO, WK DICKERSON, RR SIMPSON, J TI FREE TROPOSPHERIC OZONE PRODUCTION FOLLOWING ENTRAINMENT OF URBAN PLUMES INTO DEEP CONVECTION SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID 10-11 JUNE 1985; AMAZON BOUNDARY-LAYER; SQUALL LINE; VERTICAL-DISTRIBUTION; NUMERICAL-SIMULATION; CLOUD TRANSPORT; MIXED-LAYER; TRACE GASES; PRE-STORM; AIR AB It is shown that rapid vertical transport of air from urban plumes through deep convective clouds can cause substantial enhancement of the rate of O3 production in the free troposphere. Simulation of convective redistribution and subsequent photochemistry of an urban plume from Oklahoma City during the 1985 PRESTORM campaign shows enhancement of 03 production in the free tropospheric cloud outflow layer by a factor of almost 4. In contrast. simulation of convective transport of an urban plume from Manaus, Brazil. into a pristine free troposphere during GTE/ABLE 2B (1987), followed by a photochemical simulation. showed enhancement Of 03 production by a factor of 35. The reasons for the different enhancements are (1) intensity of cloud vertical motion; (2) initial boundary layer 03 precursor concentrations: and (3) initial amount of background free tropospheric NOx. Convective transport of ozone precursors to the middle and upper troposphere allows the resulting 03 to spread over large geographic regions, rather than being confined to the lower troposphere where loss processes are much more rapid. Conversely, as air with lower NO descends and replaces more polluted air, there is greater 03 production efficiency per molecule of NO in the boundary layer following convective transport. As a result, over 30% more ozone could be produced in the entire tropospheric column in the first 24 hours following convective transport of urban plumes. C1 UNIV MARYLAND,DEPT METEOROL,COLL PK,MD 20742. RP PICKERING, KE (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ATMOSPHERES LAB,UNIV SPACE RES ASSOC,MAIL CODE 916,GREENBELT,MD 20771, USA. RI Pickering, Kenneth/E-6274-2012; Dickerson, Russell/F-2857-2010; Thompson, Anne /C-3649-2014 OI Dickerson, Russell/0000-0003-0206-3083; Thompson, Anne /0000-0002-7829-0920 NR 47 TC 101 Z9 102 U1 2 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1992 VL 97 IS D16 BP 17985 EP 18000 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA JZ602 UT WOS:A1992JZ60200002 ER PT J AU ABBAS, MM TRAUB, WA AF ABBAS, MM TRAUB, WA TI STRATOSPHERIC MINOR CONSTITUENT DISTRIBUTIONS FROM FAR-INFRARED THERMAL EMISSION-SPECTRA SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BALLOON INTERCOMPARISON CAMPAIGN; SINGLE-AXIS PLATFORM; WATER-VAPOR; PROFILES; SPECTROSCOPY; (H2O)-O-18 AB We retrieve mixing ratio profiles Of 03, (H2O)-O-16, (H2O)-O-17, (H2O)-O-18, HF, and HCI from far-infrared thermal emission observations of the limb in the 80-220 cm-1 spectral region. The observations were made with a balloon-borne Fourier transform spectrometer as a part of the 1983 Balloon Intercomparison Campaign (BIC-2). A subset of the data was analyzed previously using the method in the work of Traub et al. [1982, 1991]; in the present paper we use an alternative method of calibration and analysis, given by Abbas et al, [1985]. The retrieved constituent profiles are compared with the measurements made with other instruments on the BIC-2 flights. The results for the concentrations of (H2O)-O-17 and (H2O)-O-18 obtained in this study indicate no isotopic enhancement or depletion with a standard deviation of about 20%. C1 HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138. RP ABBAS, MM (reprint author), NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,SPACE SCI LAB,MAIL STOP ES 55,HUNTSVILLE,AL 35812, USA. NR 33 TC 5 Z9 5 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1992 VL 97 IS D16 BP 18035 EP 18045 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA JZ602 UT WOS:A1992JZ60200005 ER PT J AU MINTON, TK NELSON, CM MOORE, TA OKUMURA, M AF MINTON, TK NELSON, CM MOORE, TA OKUMURA, M TI DIRECT OBSERVATION OF CLO FROM CHLORINE NITRATE PHOTOLYSIS SO SCIENCE LA English DT Article ID TRIATOMIC PHOTOFRAGMENT SPECTRA; NO2 PHOTODISSOCIATION; OZONE DEPLETION; 308 NM; PHOTOCHEMISTRY; CL2O2 AB Chlorine nitrate photolysis has been investigated with the use of a molecular beam technique. Excitation at both 248 and 193 nanometers led to photodissociation by two pathways, ClONO2 --> ClO + NO2 and ClONO2 --> Cl + NO3, with comparable yields. This experiment provides a direct measurement of the ClO product channel and consequently raises the possibility of an analogous channel in ClO dimer photolysis. Photodissociation of the ClO dimer is a critical step in the catalytic cycle that is presumed to dominate polar stratospheric ozone destruction. A substantial yield of ClO would reduce the efficiency of this cycle. C1 CALTECH,ARTHUR AMOS NOYES LAB CHEM PHYS,PASADENA,CA 91125. RP MINTON, TK (reprint author), JET PROP LAB,MAIL STOP 67-201,4800 OAK GROVE DR,PASADENA,CA 91109, USA. RI Okumura, Mitchio/I-3326-2013 OI Okumura, Mitchio/0000-0001-6874-1137 NR 32 TC 38 Z9 38 U1 1 U2 4 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD NOV 20 PY 1992 VL 258 IS 5086 BP 1342 EP 1345 DI 10.1126/science.258.5086.1342 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JY958 UT WOS:A1992JY95800033 PM 17778361 ER PT J AU ALTEROVITZ, SA SEKULAMOISE, PA SIEG, RM DROTOS, MN BOGNER, NA AF ALTEROVITZ, SA SEKULAMOISE, PA SIEG, RM DROTOS, MN BOGNER, NA TI ELLIPSOMETRIC STUDY OF METAL ORGANIC CHEMICALLY VAPOR-DEPOSITED III-V SEMICONDUCTOR STRUCTURES SO THIN SOLID FILMS LA English DT Article ID THICKNESS AB Metal-organic chemical vapor deposition was used to grow epitaxial layers of AlGaAs, GaAs and InGaAs on semi-insulating GaAs substrates. The ternary composition of the thick layers was determined by double-crystal X-ray diffraction (DCXRD). Variable angle spectroscopic ellipsometry was used to characterize several types of structures including relaxed single-component thick films and strained lattice multilayer structures. The thick film characterization included ternary alloy composition as determined by a numerical algorithm and interface quality. The results for the alloy composition were equal to the DCXRD results, to within the experimental errors except for the top layer of a thick AlGaAs film. The strained layer multistructures were analyzed for all layer thicknesses and alloy compositions. For most layers, the thickness was equal to the nominal values, to within the experimental errors. However, in all three In0.3Ga0.7As samples, the indium concentration estimated from the relaxed layer's InGaAs algorithm was around 21%, i.e. much lower than the nominal value. This result indicates a shift in the critical points of the dielectric function, owing to strain effects. C1 SPIRE CORP, BEDFORD, MA 01730 USA. CLEVELAND STATE UNIV, CLEVELAND, OH 44115 USA. RP ALTEROVITZ, SA (reprint author), NASA, CLEVELAND, OH 44135 USA. NR 13 TC 4 Z9 4 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD NOV 20 PY 1992 VL 220 IS 1-2 BP 241 EP 246 DI 10.1016/0040-6090(92)90579-Z PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA KA735 UT WOS:A1992KA73500041 ER PT J AU SIMONS, RN TAUB, SR YOUNG, PG AF SIMONS, RN TAUB, SR YOUNG, PG TI NOVEL COPLANAR WAVE-GUIDE TO SLOTLINE TRANSITION ON HIGH-RESISTIVITY SILICON SO ELECTRONICS LETTERS LA English DT Article DE COPLANAR WAVE-GUIDE; HIGH RESISTIVITY SILICON AB Two novel coplanar waveguide (CPW) to slotline transitions have been fabricated and tested on high resistivity silicon. The first transition uses an air bridge to couple RF power from the CPW line to the slotline and has the entire circuit on the top side of the wafer. In the second transition, the grounded CPW (GCPW) line and the slotline are on opposite sides of the wafer and are coupled electromagnetically. The measured average insertion loss and return loss per transition are better than 1.5 and 10 dB, respectively, with a bandwidth greater than 30% at C-band frequencies. RP SIMONS, RN (reprint author), NASA,LEWIS RES CTR,21000 BROOKPK RD,CLEVELAND,OH 44135, USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD, ENGLAND SG1 2AY SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD NOV 19 PY 1992 VL 28 IS 24 BP 2209 EP 2210 DI 10.1049/el:19921419 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA KA244 UT WOS:A1992KA24400006 ER PT J AU BAUSCHLICHER, CW PARTRIDGE, H SCUSERIA, GE AF BAUSCHLICHER, CW PARTRIDGE, H SCUSERIA, GE TI A COMPARISON OF THE COUPLED CLUSTER AND INTERNALLY CONTRACTED AVERAGED COUPLED-PAIR-FUNCTIONAL LEVELS OF THEORY FOR THE CALCULATION OF THE MCH2+ BINDING-ENERGIES FOR M=SC TO CU SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HIGHLY CORRELATED SYSTEMS; GAUSSIAN-BASIS SETS; MOLECULAR CALCULATIONS; ELECTRON CORRELATION; TRIPLE EXCITATIONS; ATOMS; CI(SD) AB The correlation contribution to the M-C binding energy for the MCH2+ systems can exceed 100 kcal/mol. At the self-consistent field (SCF) level, these systems can be more than 50 kcal/mol above the fragment energies. In spite of the poor zeroth-order reference, the coupled cluster single and double excitation method with a perturbational estimate of triple excitations, CCSD(T), method is shown to provide an accurate description of these systems. The maximum difference between the CCSD(T) and internally contracted averaged coupled-pair functional binding energies is 1.5 kcal/mol for CrCH2+, with the remaining systems agreeing to within 1.0 kcal/mol. C1 RICE UNIV, DEPT CHEM, HOUSTON, TX 77251 USA. RICE UNIV, RICE QUANTUM INST, HOUSTON, TX 77251 USA. RP BAUSCHLICHER, CW (reprint author), NASA, AMES RES CTR, MOFFETT FIELD, CA 94035 USA. RI Scuseria, Gustavo/F-6508-2011 NR 29 TC 28 Z9 28 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 15 PY 1992 VL 97 IS 10 BP 7471 EP 7473 DI 10.1063/1.463518 PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JY567 UT WOS:A1992JY56700043 ER PT J AU POULAIN, PM LUTHER, DS PATZERT, WC AF POULAIN, PM LUTHER, DS PATZERT, WC TI DERIVING INERTIAL WAVE CHARACTERISTICS FROM SURFACE DRIFTER VELOCITIES - FREQUENCY VARIABILITY IN THE TROPICAL PACIFIC SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID MIXED LAYER; OCEAN; OSCILLATIONS; MOTIONS; FRONT AB Two techniques have been developed for estimating statistics Of inertial OscillatiOns from satellite-tracked drifters. These techniques overcome the difficulties inherent in estimating such statistics from data dependent upon space coordinates that are a function of time. Application of these techniques to tropical surface drifter data collected during the NORPAX, EPOCS, and TOGA programs reveals a latitude-dependent, statistically significant "blue shift" of inertial wave frequency. The latitudinal dependence of the blue shift is similar to predictions based on "global" internal wave spectral models, with a superposition of frequency shifting due to modification of the effective local inertial frequency by the presence of strongly sheared zonal mean currents within 12-degrees of the equator. C1 UNIV MIAMI,COOPERAT INST MARINE & ATMOSPHER STUDIES,MIAMI,FL 33152. UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093. JET PROP LAB,PASADENA,CA 91109. NR 32 TC 19 Z9 19 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD NOV 15 PY 1992 VL 97 IS C11 BP 17947 EP 17959 DI 10.1029/92JC01381 PG 13 WC Oceanography SC Oceanography GA JZ339 UT WOS:A1992JZ33900019 ER PT J AU CHARLOCK, TP ROSE, FG AF CHARLOCK, TP ROSE, FG TI LOW-FREQUENCY VARIATIONS OF CIRCULATION AND HIGH CLOUDINESS IN THE NORTHERN EXTRATROPICS - SPATIAL AND TEMPORAL RELATIONSHIPS SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Note ID OUTGOING LONGWAVE RADIATION; AVAILABLE POTENTIAL-ENERGY; 500-MB HEIGHT FLUCTUATIONS; INTRASEASONAL TIME SCALES; BAROCLINIC WAVE-GUIDES; GEOPOTENTIAL HEIGHT; HEMISPHERE WINTER; TELECONNECTION PATTERNS; VERTICAL STRUCTURE; SATELLITE DATA AB The spatial and temporal relationships between fluctuations in geopotential height and high-cloud fractional area in low-Pass (periods greater than 10 days) and intermediate-pass (10-30 days) time scales are investigated and compared with relationships in the fast-pass (2.5-6 days) time scale. NMC 500-hPa height and Nimbus-7 THIR/TOMS high-cloud data are used for extended 6-month (October-March) winters ( 1979-85). Summary correlation maps describe the spatial phase relationships between the heights and the clouds over the full domain of the northern extratropics. As we move from the slower low-pass and intermediate-pass regimes to the fast-pass regime, the temporal variance of the height field decreases, but the temporal variance of the high cloudiness increases. Surprisingly, the 500-hPa height and high-cloud fields are more strongly correlated in the slower time scales. The spatial phase relationships between the height and cloud fields are generally different in the low-pass and fast-pass regimes. Over portions of the jet exit regions, one-half of the variance in the low-pass cloudiness can be explained by a correlation with the height fluctuations at nearby points. Over these areas, the low-pass height fluctuations are approximately equivalent barotropic, and the heights are correlated with clouds quite strongly downstream (to the east) but only weakly upstream (to the west). This contrasts with the spatial phase relationships found in the more baroclinic fast-pass regime, where fluctuations in height are correlated with clouds by about the same absolute magnitude either downstream or upstream. An analysis of the temporal evolution of intermediate-pass height and cloud fields reveals the cloud signal of two-dimensional Rossby wave dispersion over a small portion of the northern extratropics. C1 LOCKHEED ENGN & SCI CO,HAMPTON,VA. RP CHARLOCK, TP (reprint author), NASA,DIV ATMOSPHER SCI,LANGLEY RES CTR,HAMPTON,VA 23681, USA. OI Rose, Fred G/0000-0003-0769-0772 NR 47 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD NOV 15 PY 1992 VL 49 IS 22 BP 2157 EP 2170 DI 10.1175/1520-0469(1992)049<2157:LFVOCA>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KA815 UT WOS:A1992KA81500009 ER PT J AU BISWAS, A PINNICK, RG XIE, JG RUEKGAUER, TE ARMSTRONG, RL AF BISWAS, A PINNICK, RG XIE, JG RUEKGAUER, TE ARMSTRONG, RL TI OBSERVATIONS OF STIMULATED RAMAN-SCATTERING AND LASER-INDUCED BREAKDOWN IN MILLIMETER-SIZED DROPLETS SO OPTICS LETTERS LA English DT Article ID MORPHOLOGY-DEPENDENT RESONANCES; WAVELENGTH DEPENDENCE; LIQUID DROPLETS; EMISSION; TIME; MICRODROPLETS; SPECTROSCOPY; LEVITATION; GENERATION; ENERGY AB We report the first observations, to our knowledge, of nonlinear optical effects in large (millimeter-sized) droplets. Stimulated Raman scattering (SRS) and laser-induced breakdown (LIB) are simultaneously observed in acoustically levitated millimeter-sized glycerol droplets irradiated by either a frequency-doubled (532-nm) or a frequency-tripled (355-nm) Nd:YAG laser. The two processes, which occur above a nearly coincident irradiation threshold, are conjectured to arise from a common initiation mechanism: self-focusing. LIB generates vapor bubbles within the droplet, resulting in the quenching of SRS emission. C1 USA,RES LAB,WHITE SANDS MISSILE RANGE,NM 88002. NEW MEXICO STATE UNIV,DEPT PHYS,LAS CRUCES,NM 88003. RP BISWAS, A (reprint author), JET PROP LAB,MS 183-401,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 26 TC 5 Z9 5 U1 1 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD NOV 15 PY 1992 VL 17 IS 22 BP 1569 EP 1571 DI 10.1364/OL.17.001569 PG 3 WC Optics SC Optics GA JX226 UT WOS:A1992JX22600005 PM 19798248 ER PT J AU FLETCHER, DG MCKENZIE, RL AF FLETCHER, DG MCKENZIE, RL TI SINGLE-PULSE MEASUREMENTS OF DENSITY AND TEMPERATURE IN A TURBULENT, SUPERSONIC-FLOW USING UV LASER SPECTROSCOPY SO OPTICS LETTERS LA English DT Article ID FLUORESCENCE AB Nonintrusive measurements of density and temperature and their turbulent fluctuation levels have been obtained in the boundary layer of an unseeded, Mach 2 wind tunnel flow. The spectroscopic technique that was used to make the measurements is based on the combination of laser-induced oxygen fluorescence and Raman scattering by oxygen and nitrogen from the same laser pulse. Results from this demonstration experiment compare favorably with previous measurements obtained in the same facility from conventional probes and an earlier spectroscopic technique. RP FLETCHER, DG (reprint author), NASA,AMES RES CTR,MS 229-1,MOFFETT FIELD,CA 94035, USA. NR 8 TC 10 Z9 10 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD NOV 15 PY 1992 VL 17 IS 22 BP 1614 EP 1616 DI 10.1364/OL.17.001614 PG 3 WC Optics SC Optics GA JX226 UT WOS:A1992JX22600020 PM 19798263 ER PT J AU EBERHART, ME DONOVAN, MM OUTLAW, RA AF EBERHART, ME DONOVAN, MM OUTLAW, RA TI ABINITIO CALCULATIONS OF OXYGEN DIFFUSIVITY IN GROUP-IB TRANSITION-METALS SO PHYSICAL REVIEW B LA English DT Note AB First-principles investigations of oxygen transport through Cu, Ag, and Au have revealed subtle changes in the response of the total charge density to the presence of 0 atoms in the octahedral holes of these metals. In both Cu and Ag, these changes are characterized by a decrease in the magnitude of the curvature of the charge density normal to the metal-metal first-neighbor atoms. In Au there is an increase in the magnitude of this curvature. Associating the curvature of the charge density normal to the internuclear axis with the barrier to oxygen diffusion provides a consistent explanation of the difference in diffusivity of 0 through Cu, Ag, and Au. C1 US DOE,WASHINGTON,DC 20585. NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP EBERHART, ME (reprint author), COLORADO SCH MINES,DEPT MET & MAT ENGN,GOLDEN,CO 80401, USA. NR 17 TC 44 Z9 47 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 19 BP 12744 EP 12747 DI 10.1103/PhysRevB.46.12744 PG 4 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900075 ER PT J AU MILLIKEN, AM MANION, SJ KAISER, WJ BELL, LD HECHT, MH AF MILLIKEN, AM MANION, SJ KAISER, WJ BELL, LD HECHT, MH TI PROBING HOT-CARRIER TRANSPORT AND ELASTIC-SCATTERING USING BALLISTIC-ELECTRON-EMISSION MICROSCOPY SO PHYSICAL REVIEW B LA English DT Note ID BAND-STRUCTURE; INTERFACE; SPECTROSCOPY AB Ballistic-electron-emission microscopy (BEEM) has been used to characterize electron transport and scattering in metal/semiconductor structures. A SiO2 layer at the Au/Si interface was patterned to form transmitting and nontransmitting regions. By analyzing the BEEM current profiles at the boundaries of these regions, information on the spatial distribution of electrons after transport through the Au layer can be derived. A detailed comparison is made between the results presented here and models which involve modification of the electron distribution by scattering. RP MILLIKEN, AM (reprint author), JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109, USA. NR 11 TC 47 Z9 47 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 19 BP 12826 EP 12829 DI 10.1103/PhysRevB.46.12826 PG 4 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900098 ER PT J AU AHARONIAN, FA BHATTACHARJEE, P SCHRAMM, DN AF AHARONIAN, FA BHATTACHARJEE, P SCHRAMM, DN TI PHOTON PROTON RATIO AS A DIAGNOSTIC-TOOL FOR TOPOLOGICAL DEFECTS AS THE SOURCES OF EXTREMELY HIGH-ENERGY COSMIC-RAYS SO PHYSICAL REVIEW D LA English DT Article ID TRIPLET PAIR PRODUCTION; GAMMA-RAYS; ELECTRONS; STRINGS; SPECTRUM AB The hypothesis of topological defects (from grand unified and/or Planck scales) as the sources of extremely high-energy (> 10(18) eV) cosmic rays predicts an unusually high content of gamma rays at energies E greater than or similar to 10(20) eV (gamma/p greater-than-or-equal-to 1) and E less than or similar 10(14) eV (gamma/p greater than or similar to 10(-3)). This can be used as a signature for testing the hypothesis in forthcoming experiments. C1 NASA,FERMI NATL ACCELERATOR LAB,CTR ASTROPHYS,BATAVIA,IL 60510. RP AHARONIAN, FA (reprint author), UNIV CHICAGO,5640 S ELLIS AVE,CHICAGO,IL 60637, USA. NR 35 TC 61 Z9 63 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 1992 VL 46 IS 10 BP 4188 EP 4192 DI 10.1103/PhysRevD.46.4188 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400010 ER PT J AU KOLB, EW TKACHEV, II AF KOLB, EW TKACHEV, II TI SEMICLASSICAL CORRECTIONS TO THERMAL-ACTIVATION SO PHYSICAL REVIEW D LA English DT Article ID FALSE VACUUM; BUBBLES AB The decay of a metastable phase through the nucleation of bubbles of the true-vacuum phase can occur at a nonzero temperature through classical thermal activation, with the rate per volume P is-proportional-to exp(-F(C)/k(B)T), where F(C) is the free energy for a critical bubble and Tis the temperature. In this paper we calculate order HBAR corrections to this rate. These corrections represent processes where the field tunnels through the potential barrier starting from a state of free energy F < F(C), and provide a smooth interpolation between the high-temperature and zero-temperature decay rates. We confirm that the quantum corrections are of the same order as the classical results at large T. C1 NASA,FERMI NATL ACCELERATOR LAB,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. UNIV CHICAGO,ENRICO FERMI INST,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. ACAD SCI RUSSIA,INST NUCL RES,MOSCOW 117312,USSR. RP KOLB, EW (reprint author), UNIV CALIF SANTA BARBARA,INST THEORET PHYS,SANTA BARBARA,CA 93106, USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 1992 VL 46 IS 10 BP 4235 EP 4241 DI 10.1103/PhysRevD.46.4235 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400016 ER PT J AU ALTY, LJ DEATH, PD DOWKER, HF AF ALTY, LJ DEATH, PD DOWKER, HF TI QUANTUM WORMHOLE STATES AND LOCAL SUPERSYMMETRY SO PHYSICAL REVIEW D LA English DT Article ID COSMOLOGICAL CONSTANT; STRING THEORY; QUANTIZATION; SUPERGRAVITY; FIELDS AB The existence of quantum wormhole states is studied in a minisuperspace model with local supersymmetry, where supergravity is coupled to a massless multiplet consisting of a spin-1/2 and complex scalar field. The geometry is taken to be that of a k = + 1 Friedmann universe, the other fields being subject to a suitable homogeneous ansatz. An integral expression is found for the wormhole ground state, and the other quantum wormhole states can be found from it by simple differential operations. The effective mass of the scalar-spin-1/2 multiplet remains zero when wormhole effects are included. C1 NASA,FERMILAB ASTROPHYS CTR,FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP ALTY, LJ (reprint author), UNIV CAMBRIDGE,DEPT APPL MATH & THEORET PHYS,SILVER ST,CAMBRIDGE CB3 9EW,ENGLAND. NR 23 TC 21 Z9 21 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 1992 VL 46 IS 10 BP 4402 EP 4412 DI 10.1103/PhysRevD.46.4402 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400031 ER PT J AU LAMOURI, A KRAINSKY, IL AF LAMOURI, A KRAINSKY, IL TI ANGLE-RESOLVED INVERSE PHOTOEMISSION FROM ONE MONOLAYER OF BA ON W(001) SO SURFACE SCIENCE LA English DT Article ID TRANSITION-METAL SURFACES; ELECTRONIC-STRUCTURE; STATES; TUNGSTEN; ADSORPTION; CS; OXIDATION; MO(001); SYSTEM; MODEL AB We have investigated the physical and electronic properties of one monolayer (ML) of Ba on the W(001) face using low-energy electron diffraction (LEED), work function measurements and angle-resolved inverse photoelectron spectroscopy (ARIPES). It was found that the work function of the W(001) was lowered by approximately 2 eV after adsorption of one ML of Ba. At this coverage an ordered c(2 x 2) adlayer was observed. The ARIPES experimental data taken along the DELTABAR symmetry line of the W(001) surface Brillouin zone (SBZ) indicate strong emission above the Fermi energy (E(F)) dominated by transitions to the Ba d-surface states and a W bulk state. C1 NASA,LEWIS RES CTR,21000 BROOKPARK RD,CLEVELAND,OH 44135. NR 33 TC 15 Z9 15 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD NOV 15 PY 1992 VL 278 IS 3 BP 286 EP 290 DI 10.1016/0039-6028(92)90665-S PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA JX587 UT WOS:A1992JX58700007 ER PT J AU BAUSCHLICHER, CW PARTRIDGE, H SODUPE, M LANGHOFF, SR AF BAUSCHLICHER, CW PARTRIDGE, H SODUPE, M LANGHOFF, SR TI THEORETICAL-STUDY OF THE ALKALINE-EARTH METAL SUPEROXIDES BEO2 THROUGH SRO2 SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID GAUSSIAN-BASIS SETS; GTO BASIS-SETS; MATRIX REACTIONS; ROW ATOMS; MOLECULAR CALCULATIONS; ELECTRON CORRELATION; OXYGEN MOLECULES; 2ND-ROW ATOMS; CONTRACTION; SPECTRA AB Three competing bonding mechanisms have been identified for the alkaline-earth metal superoxides: these result in a change in the optimal structure and ground state as the alkaline-earth metal becomes heavier. For example, BeO2 has a linear 3SIGMA(g)-ground-state structure, whereas both CaO2 and SrO2 have C2v 1A1 structures. For MgO2, the theoretical calculations are less definitive, as the 3A2 C2v structure is computed to lie only about 3 kcal/mol above the 3SIGMA(g)- linear structure. The bond dissociation energies for the alkaline-earth metal superoxides have been computed using extensive Gaussian basis sets and treating electron correlation at the modified coupled-pair functional or coupled-cluster singles and doubles level with a perturbational estimate of the triple excitations. Our best estimates for the M-O2 dissociation energies are 88 +/- 4, 25 +/- 4, 54 +/- 4, and 54 +/- 6 kcal/mol for BeO2, MgO2, CaO2, and SrO2, respectively. RP BAUSCHLICHER, CW (reprint author), NASA,AMES RES CTR,MOFFETT FIELD,CA 94035, USA. RI Sodupe, Mariona/E-9352-2013 OI Sodupe, Mariona/0000-0003-0276-0524 NR 40 TC 37 Z9 37 U1 0 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD NOV 12 PY 1992 VL 96 IS 23 BP 9259 EP 9264 DI 10.1021/j100202a036 PG 6 WC Chemistry, Physical SC Chemistry GA JX921 UT WOS:A1992JX92100036 ER PT J AU BURTON, MG HOLLENBACH, DJ TIELENS, AGGM AF BURTON, MG HOLLENBACH, DJ TIELENS, AGGM TI MIDINFRARED ROTATIONAL LINE EMISSION FROM INTERSTELLAR MOLECULAR-HYDROGEN SO ASTROPHYSICAL JOURNAL LA English DT Article DE INFRARED, INTERSTELLAR, LINES; ISM, MOLECULES; MOLECULAR PROCESSES; SHOCK WAVES ID SUPERNOVA REMNANT IC-443; PHOTODISSOCIATION REGIONS; ORION NEBULA; SHOCK-WAVES; CLOUDS; MODEL; GAS; OMC-1; H-2; H2 AB We have modeled the line emission from the v = 0-0 S(O), S(2), and S(3), and the v = 1-0 and v = 2-1 S(1) transitions of molecular hydrogen in clouds exposed to high far-ultraviolet fluxes (i.e., photodissociation regions or PDRs) and in shocks. In particular, we have studied the lowest pure rotational H-2 transitions [the 0-0 S(0) and 0-0 S(1) lines], at 28 and 17 mum, respectively. We find that, in PDRs, the emission comes from warm (T greater than or similar to 100 K) molecular gas, situated at optical depths A(v) greater than or similar to 1, beyond the hot atomic surface layer of the clouds. For FUV fields, G0 = 10(3)-10(5) times the average interstellar field and densities n = 10(3)-10(7) CM-3, the typical line intensities are in the range 10(-6) to 10(-4) ergs s-1 cm-2 sr-1. We compare the predictions for the line intensities from both C-type and J-type shock models. For both nondissociative and dissociative molecular shocks, in the same density range, the line intensities range from 10(-6) to 10(-3) ergs s-1 cm-2 sr-1. In the faster, dissociative shocks (v(s) greater than or similar to 25-30 km s-1), the H-2 line emission arises from reformed molecules, downstream of the shock front. Shocked line emission may be detectable from lower velocity shocks (i.e., v(s) approximately 5 km s-1) than previously observed. Measurements of the relative line ratios may be used to help discriminate between competing models for the shock excitation of molecular gas. Observations of these lines will also provide a powerful probe of the extensive regions of warm molecular gas in the Galaxy. The results are applied to recent observations of the 0-0 S(1) transition in both the PDR and the shocked ps in Orion. The Infrared Satellite Observatory (ISO) should detect the v = 0-0 low-J transitions in numerous active regions. C1 NASA,AMES RES CTR,DIV SPACE SCI,MOFFETT FIELD,CA 94035. RP BURTON, MG (reprint author), ANGLO AUSTRALIAN OBSERV,EPPING LAB,POB 296,EPPING,NSW 2121,AUSTRALIA. OI Burton, Michael/0000-0001-7289-1998 NR 37 TC 115 Z9 115 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1992 VL 399 IS 2 BP 563 EP 572 DI 10.1086/171947 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV806 UT WOS:A1992JV80600018 ER PT J AU SCHMELZ, JT HOLMAN, GD BROSIUS, JW GONZALEZ, RD AF SCHMELZ, JT HOLMAN, GD BROSIUS, JW GONZALEZ, RD TI CORONAL MAGNETIC-STRUCTURES OBSERVING CAMPAIGN .2. MAGNETIC AND PLASMA PROPERTIES OF A SOLAR ACTIVE REGION SO ASTROPHYSICAL JOURNAL LA English DT Article DE SUN, CORONA; SUN, MAGNETIC FIELDS; SUN, RADIO RADIATION; SUN, X-RAYS; GAMMA-RAYS ID X-RAY; MICROWAVE; EMISSION; FIELDS; LOOPS; LIMB AB Simultaneous soft X-ray, microwave, and photospheric magnetic field observations were taken during the Coronal Magnetic Structures Observing Campaign (CoMStOC). The plasma electron temperatures and emission measures determined from the X-ray data are used to predict the intensity and structure of the thermal bremsstrahlung emission at 20 and 6 cm. Comparing these predictions with the microwave observations, it is found that the 20 cm structure is very similar to that expected from the X-rays, but a substantial amount of the 6 cm emission was resolved out. The predicted 20 cm brightness temperatures are higher than the observed, requiring cool absorbing material (T(e) less-than-or-equal-to 500,000 K) between the hot X-ray plasma and the observer. The absorption mechanism in the cool plasma at 20 cm is most likely thermal bremsstrahlung, requiring coronal magnetic fields as high as 150 G. ''Coronal Magnetograms,'' made by extrapolating the photospheric longitudinal field using the Sakurai code, show that appropriate values of the total field are reached at heights of 6000-10,000 km above the photosphere (at many but not all locations). The model proposed to explain the full set of observations requires polarization inversion of the 20 cm emission high in the solar atmosphere where the longitudinal component of the magnetic field reverses direction (where the magnetic field is transverse to the line of sight). Such a reversal is found with the magnetic field extrapolation code. At 6 cm, the polarization modes must be strongly coupled so that no polarization inversion is observed. These results require a density approximately 10(8) cm-3 at the location of the field reversal. C1 NASA,GODDARD SPACE FLIGHT CTR,LASP,GREENBELT,MD 20771. NASA,GODDARD SPACE FLIGHT CTR,HUGHES STX,GREENBELT,MD 20771. NRAO,CHARLOTTESVILLE,VA 22903. RP SCHMELZ, JT (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ARC LOCKHEED,CODE 682,GREENBELT,MD 20771, USA. RI Holman, Gordon/C-9548-2012 NR 29 TC 29 Z9 29 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1992 VL 399 IS 2 BP 733 EP & DI 10.1086/171966 PN 1 PG 0 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV806 UT WOS:A1992JV80600037 ER PT J AU BOWKER, DE DAVIS, RE AF BOWKER, DE DAVIS, RE TI INFLUENCE OF ATMOSPHERIC AEROSOLS AND DESERT REFLECTANCE PROPERTIES ON SATELLITE RADIANCE MEASUREMENTS SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID BIDIRECTIONAL REFLECTANCE; MODEL AB The influence of surface bidirectional reflectance factors, including shadowing, and of atmospheric aerosol variability are modelled for their effects on the remote sensing of desert targets from space in the 0.7 mum region at high spatial resolution. The white sand reflectance data of Salomonson are used as the basis for the simulation. The effects of the surface bi-directional reflectance and atmospheric aerosol on the nadir-normalized reflectance measured at the satellite are discussed individually and jointly. The net influence of these two factors is shown to depend on the magnitude of other parameters, such as the surface reflectance and solar zenith angle. RP BOWKER, DE (reprint author), NASA,LANGLEY RES CTR,HAMPTON,VA 23665, USA. NR 33 TC 3 Z9 3 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD NOV 10 PY 1992 VL 13 IS 16 BP 3105 EP 3126 PG 22 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA JX743 UT WOS:A1992JX74300012 ER PT J AU DEMETS, C AF DEMETS, C TI OBLIQUE CONVERGENCE AND DEFORMATION ALONG THE KURIL AND JAPAN TRENCHES SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID MOMENT TENSOR SOLUTIONS; SUBDUCTION ZONES; ALEUTIAN ISLANDS; PLATE MOTIONS; ARC; PACIFIC; EARTHQUAKES; PARAMETERS; TECTONICS; FAULTS AB The hypothesis that present-day deformation within the southern Kuril forearc is driven by oblique subduction of the Pacific plate is tested using 397 horizontal slip directions derived from shallow-thrust earthquakes from the Kuril and Japan trenches for the period 1963-1991. A simple two-plate model fits the 397 slip vectors significantly worse than a model that permits strike-slip motion of the southern Kuril forearc relative to the overlying plate. Weighted, mean slip directions along the southern Kuril trench are systematically rotated toward the direction orthogonal to the trench, which implies that the net convergence is partitioned into less oblique subduction and trench-parallel displacement of the southern Kuril forearc. The angular discrepancy between the observed slip direction and the direction predicted by the NUVEL-1 Pacific-North America Euler vector implies that the southern Kuril forearc translates 6-11 mm yr-1 to the southwest relative to the overlying North American plate. These results are consistent with geologically, geodetically, and seismologically observed convergence at the leading edge of the forearc sliver in southern Hokkaido and with previously inferred extension at the training edge of the sliver, which is located at the Bussol Strait at 46-degrees-N. The percentage of the oblique component of the rigid plate convergence vector that is transferred into forearc strike-slip motion is only 30%, which may be evidence that the Hokkaido/Honshu bend in the trench hinders southwest forearc motion or that the greater strength of oceanic forearcs impedes motion along forearc strike-slip faults. C1 JET PROP LAB, PASADENA, CA 91109 USA. NR 37 TC 81 Z9 85 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD NOV 10 PY 1992 VL 97 IS B12 BP 17615 EP 17625 DI 10.1029/92JB01306 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JY189 UT WOS:A1992JY18900026 ER PT J AU DEMETS, C AF DEMETS, C TI A TEST OF PRESENT-DAY PLATE GEOMETRIES FOR NORTHEAST ASIA AND JAPAN SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID AMERICAN; TECTONICS; MOTION; ARC; DEFORMATION; SUBDUCTION; BOUNDARY; RATES AB Alternative geometries for the present-day configuration of plate boundaries in northeast Asia and Japan are tested using NUVEL-1 and 256 horizontal earthquake slip vectors from the Japan and northern Kuril trenches. Statistical analysis of the slip vectors is used to determine whether the North American, Eurasian, or Okhotsk plate overlies the trench. Along the northern Kuril trench, slip vectors are well-fit by the NUVEL-1 Pacific-North America Euler pole, but are poorly fit by the Pacific-Eurasia Euler pole. Results for the Japan trench are less conclusive, but suggest that much of Honshu and Hokkaido are also pan of the North American plate. The simplest geometry consistent with the trench slip vectors is a geometry in which the North American plate extends south to 41-degrees-N, and possibly includes northern Honshu and southern Hokkaido. Although these results imply that the diffuse seismicity that connects the Lena River delta to Sakhalin Island and the eastern Sea of Japan records motion between Eurasia and North America, onshore geologic and seismic data define an additional belt of seismicity in Siberia that cannot be explained with this geometry. Assuming that these two seismic belts constitute evidence for an Okhotsk block, two published kinematic models for motion of the Okhotsk block are tested. The first model, which predicts motion of up to 15 mm yr-1 relative to North America, is rejected because Kuril and Japan trench slip vectors are fit more poorly than for the simpler geometry described above. The second model gives a good fit to the trench slip vectors, but only if Okhotsk-North America motion is slower than 5 mm yr-1. C1 JET PROP LAB, PASADENA, CA 91109 USA. NR 31 TC 40 Z9 41 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD NOV 10 PY 1992 VL 97 IS B12 BP 17627 EP 17635 DI 10.1029/92JB01335 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JY189 UT WOS:A1992JY18900027 ER PT J AU FATHAUER, RW GEORGE, T JONES, EW PIKE, WT KSENDZOV, A VASQUEZ, RP AF FATHAUER, RW GEORGE, T JONES, EW PIKE, WT KSENDZOV, A VASQUEZ, RP TI NEW CLASS OF SI-BASED SUPERLATTICES - ALTERNATING LAYERS OF CRYSTALLINE SI AND POROUS AMORPHOUS SI1-XGEX ALLOYS SO APPLIED PHYSICS LETTERS LA English DT Article ID QUANTUM AB Superlattices consisting of alternating layers of crystalline Si and porous amorphous Si1-xGex have been fabricated. This is accomplished by first growing a Si/Si0.7Ge0.3 superlattice by molecular beam epitaxy, followed by Ar-ion milling to form mesa structures, and finally by immersion in HF:HNO3:H2O. This solution creates a porous structure similar to that created by anodic etching, and a high selectivity is observed for the conversion of the alloy layers relative to the Si layers. The degree of selectivity is found to depend on alloy layer thickness and strain. Superlattices have been fabricated from 1-mum wide mesas with Si0.7Ge0.3 layers fully converted to 5-nm thick porous amorphous material. RP FATHAUER, RW (reprint author), JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109, USA. NR 15 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 9 PY 1992 VL 61 IS 19 BP 2350 EP 2352 DI 10.1063/1.108240 PG 3 WC Physics, Applied SC Physics GA JW880 UT WOS:A1992JW88000032 ER PT J AU NARDI, E ROULET, E TOMMASINI, D AF NARDI, E ROULET, E TOMMASINI, D TI GLOBAL ANALYSIS OF FERMION MIXING WITH EXOTICS SO NUCLEAR PHYSICS B LA English DT Article ID HEAVY FLAVOR PRODUCTION; HADRONIC Z0 DECAYS; ELECTROWEAK RADIATIVE-CORRECTIONS; BRANCHING RATIO BR(B->L+X); FORWARD-BACKWARD ASYMMETRY; ATOMIC PARITY VIOLATION; OPPOSITE-SIGN DIMUONS; STANDARD MODEL; E+E ANNIHILATION; NEUTRAL-CURRENT AB We analyze the limits on deviations of the lepton and quark weak-couplings from their standard model values in a general class of models where the known fermions are allowed to mix with new heavy particles with exotic SU(2) x U(1) quantum number assignments (left-handed singlets or right-handed doublets). These mixings appear in many extensions of the electroweak theory such as models with mirror fermions, E6 models, etc. Our results update previous analyses and improve considerably the existing bounds. As experimental constraints we use the new results on M(Z), GAMMA(Z), on the Z partial decay-widths and on the asymmetries measured at the Z-resonance, as well as updated results on the W-mass, on deep-inelastic nu-q and nu-e scattering and on atomic parity violation. Present constraints on lepton universality, unitarity of the quark mixing matrix and induced right-handed currents are also included. A global analysis of all these data leads to upper limits on the mixing factors s2 = sin2theta(mix). When just one mixing is constrained at a time, we obtain for most of the fermions the tight limits s2 less than or similar to 0.002 divided-by 0.01 at 90% C.L. For u(R), c(R) and nu(tau) the bounds are s2 < 0.03, however if nu(tau) mixes with an ordinary heavy neutrino the constraint is s2 < 0.1 and a signal of non-zero mixing at 90% C.L. is found. For s(R) and b(R) we find the much weaker bounds s2 less than or similar to 0.35. The constraints are weakened by a factor between 2 and 5 if accidental cancellations among different mixings are allowed to occur. C1 SCUOLA INT SUPER STUDI AVANZATI,I-34014 TRIESTE,ITALY. IST NAZL FIS NUCL,TRIESTE,ITALY. NASA,FERMILAB ASTROPHYS CTR,FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP NARDI, E (reprint author), UNIV MICHIGAN,RANDALL LAB PHYS,ANN ARBOR,MI 48109, USA. RI Tommasini, Daniele/L-4718-2014; OI Tommasini, Daniele/0000-0002-7997-3088; Nardi, Enrico/0000-0001-7165-3808 NR 125 TC 76 Z9 76 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD NOV 9 PY 1992 VL 386 IS 2 BP 239 EP 266 DI 10.1016/0550-3213(92)90566-T PG 28 WC Physics, Particles & Fields SC Physics GA KC702 UT WOS:A1992KC70200001 ER PT J AU HERMAN, J AF HERMAN, J TI HOT PAPERS - ATMOSPHERIC SCIENCES - TOTAL OZONE TRENDS DEDUCED FROM NIMBUS-7-TOMS DATA BY STOLARSKI,R.S., BLOOMFIELD,P., MCPETERS,R.D., HERMAN,J.R. SO SCIENTIST LA English DT Article AB An atmospheric scientist discusses his study of the ozone layer. RP HERMAN, J (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SCIENTIST INC PI PHILADELPHIA PA 3600 MARKET ST SUITE 450, PHILADELPHIA, PA 19104 SN 0890-3670 J9 SCIENTIST JI Scientist PD NOV 9 PY 1992 VL 6 IS 22 BP 15 EP 15 PG 1 WC Information Science & Library Science; Multidisciplinary Sciences SC Information Science & Library Science; Science & Technology - Other Topics GA JW606 UT WOS:A1992JW60600016 ER PT J AU JAYATILAKA, D LEE, TJ AF JAYATILAKA, D LEE, TJ TI THE FORM OF SPIN ORBITALS FOR OPEN-SHELL RESTRICTED HARTREE-FOCK REFERENCE FUNCTIONS SO CHEMICAL PHYSICS LETTERS LA English DT Article ID COUPLED-CLUSTER METHOD; PLESSET PERTURBATION-SERIES; CONFIGURATION-INTERACTION; VIBRATIONAL FREQUENCIES; ELECTRON CORRELATION; TRIPLE EXCITATIONS; SYMMETRY-BREAKING; SINGLES; ENERGY; CCSD AB A new set of spin orbitals is proposed for single-reference correlation procedures based on an open-shell restricted Hartree-Fock (RHF) reference function. The spatial parts of the new spin orbitals are from an open-shell RHF calculation. The spin part of the doubly occupied (or unoccupied) orbitals is the usual alpha or beta spin function, but the spin part of the singly occupied and singly virtual orbitals takes the form sigma+ = (1/square-root 2) (alpha + beta) and sigma- = (1/square-root 2) (alpha - beta), respectively. These spin orbitals form a complete, orthonormal set. The RHF single determinant based on these spin orbitals is an S2 eigenfunction, but a linear combination of S(z) eigenfunctions. The advantage of these spin orbitals is that equations for perturbation theory or coupled-cluster theory are symmetric in the spin indices and hence the number of independent parameters to be determined is dramatically reduced. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RI Jayatilaka, Dylan/B-3498-2012; Lee, Timothy/K-2838-2012 OI Jayatilaka, Dylan/0000-0002-3349-5834; NR 33 TC 48 Z9 48 U1 2 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD NOV 6 PY 1992 VL 199 IS 3-4 BP 211 EP 219 DI 10.1016/0009-2614(92)80108-N PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JV972 UT WOS:A1992JV97200001 ER PT J AU BAUSCHLICHER, CW PARTRIDGE, H DYALL, KG AF BAUSCHLICHER, CW PARTRIDGE, H DYALL, KG TI THE 2-SIGMA+-2-PI SEPARATION IN KO SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ELECTRON CORRELATION; BASIS-SETS; STATES; ATOMS; MOLECULES; 1ST-ROW; ALKALI AB The 2SIGMA+-2PI separation in KO is investigated using large basis sets and high levels of correlation treatment. Relativistic effects are included at the Dirac-Fock level and reduce the separation only slightly. The basis set superposition error is considered in detail. On the basis of these calculations, our best estimate places the 2PI3/2 state about 200 cm-1 above the ground 2SIGMA+ state in agreement with our previous estimate. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. ELORET INST,PALO ALTO,CA 94303. NR 20 TC 13 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD NOV 6 PY 1992 VL 199 IS 3-4 BP 225 EP 228 DI 10.1016/0009-2614(92)80110-W PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JV972 UT WOS:A1992JV97200003 ER PT J AU GOLOMBEK, MP BANERDT, WB TANAKA, KL TRALLI, DM AF GOLOMBEK, MP BANERDT, WB TANAKA, KL TRALLI, DM TI A PREDICTION OF MARS SEISMICITY FROM SURFACE FAULTING SO SCIENCE LA English DT Article ID THARSIS REGION; STRESS; SYRIA AB The shallow seismicity of Mars has been estimated by measurement of the total slip on faults visible on the surface of the planet throughout geologic time. Seismicity was calibrated with estimates based on surface structures on the moon and measured lunar seismicity that includes the entire seismogenic lithosphere. Results indicate that Mars is seismically active today, with a sufficient number of detectable marsquakes to allow seismic investigations of its interior. C1 US GEOL SURVEY,FLAGSTAFF,AZ 86001. RP GOLOMBEK, MP (reprint author), JET PROP LAB,MAIL STOP 183-501,PASADENA,CA 91109, USA. NR 26 TC 37 Z9 37 U1 0 U2 1 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD NOV 6 PY 1992 VL 258 IS 5084 BP 979 EP 981 DI 10.1126/science.258.5084.979 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JW796 UT WOS:A1992JW79600030 PM 17794594 ER PT J AU HUANG, YQ HILL, YD SODUPE, M BAUSCHLICHER, CW FREISER, BS AF HUANG, YQ HILL, YD SODUPE, M BAUSCHLICHER, CW FREISER, BS TI GAS-PHASE CHEMISTRY OF SC(CH3)2+ WITH ALKENES - ACTIVATION OF ALLYLIC C-H BONDS BY A D(0) SYSTEM AND THE MIGRATORY INSERTION OF C=C BONDS INTO SC+-CH3 BONDS SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TRANSFORM MASS-SPECTROMETRY; TRANSITION-METAL IONS; COLLISION-INDUCED DISSOCIATION; ORGANOMETALLIC CHEMISTRY; CARBON HYDROGEN; SCANDIUM IONS; PERMETHYLSCANDOCENE; REACTIVITY; ALKYL; DERIVATIVES AB The gas-phase chemistry of Sc(CH3)2+ with alkenes was studied by Fourier transform mass spectrometry. The metal center on Sc(CH3)2+ is d0, providing an opportunity to study alternative mechanisms of C-C or C-H activation other than the most common one involving oxidative addition. The elimination of H-2 is observed in the reaction of Sc(CH3)2+ with ethylene, and the product ScC4H8+ further reacts with ethylene to form the dehydrogenation product, ScC6H10+. Structure studies indicate that the ScC4H8+ and ScC6H10+ ions have a metal(methyl)(allyl) and metal-bisallyl structure, respectively, consistent with a proposed reaction mechanism involving the consecutive migratory insertion of ethylenes into the scandium-methyl bonds. In addition, theoretical calculations indicate that the metal(methyl)(allyl) structure is between 10 and 20 kcal/mol more stable than the metal(1-butene) isomer. Sc(CH3)2+ reacts with propene to form predominantly ScC4H8+ by loss of CH4, with minor amounts of ScC3H4+ and ScC4H6+ also observed. ScC4H6+ is formed as either the exclusive or the predominant production in the reactions of Sc(CH3)2+ with butenes. Sc(CH3)2+ reacts with cyclopentene to form predominantly ScC6H8+ by losing CH4 and H-2. The further reaction of ScC6H8+ with cyclopentene forms scandocenium, ScC10H10+. The reactions of cyclohexene and cycloheptene with Sc(CH3)2+ are analogous to that of cyclopentene. Isotope labeling studies with Sc(CD3)2+ and other structure studies indicate that all of the alkenes studied, with the exception of ethylene, react with Sc(CH3)2+ via a multicentered sigma-bond metathesis mechanism to activate allylic C-H bonds. Finally, the dehydrogenation reactions of Sc+ with n-butane and neopentane were revisited, and a new mechanism is proposed for such chemistry in light of the new results from this study. C1 PURDUE UNIV,DEPT CHEM,W LAFAYETTE,IN 47907. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RI Sodupe, Mariona/E-9352-2013 OI Sodupe, Mariona/0000-0003-0276-0524 NR 40 TC 17 Z9 17 U1 2 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD NOV 4 PY 1992 VL 114 IS 23 BP 9106 EP 9111 DI 10.1021/ja00049a050 PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA JW797 UT WOS:A1992JW79700050 ER PT J AU THOMASON, LW AF THOMASON, LW TI OBSERVATIONS OF A NEW SAGE-II AEROSOL EXTINCTION MODE FOLLOWING THE ERUPTION OF MT-PINATUBO SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB In the aftermath of the eruption of Mt. Pinatubo, multiwavelength stratospheric aerosol extinction measurements by the satellite-borne Stratospheric Aerosol and Gas Experiment (SAGE II) revealed the presence of a previously unobserved mode of aerosol that exhibited high extinction but a small inferred particle size. This mode may represent a transitional phase between the very small aerosol created by gas-to-particle conversion and a quasi-steady state, post-volcanic aerosol that exhibits both large extinction and large particle size. The presence of a transitional small aerosol mode may have a significant impact on chemical and radiative processes in the stratosphere. RP THOMASON, LW (reprint author), NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,MAIL STOP 475,HAMPTON,VA 23681, USA. OI Thomason, Larry/0000-0002-1902-0840 NR 10 TC 36 Z9 36 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD NOV 3 PY 1992 VL 19 IS 21 BP 2179 EP 2182 DI 10.1029/92GL02185 PG 4 WC Geosciences, Multidisciplinary SC Geology GA JY496 UT WOS:A1992JY49600019 ER PT J AU GEDNEY, RT WRIGHT, DL BALOMBIN, JL SOHN, PY CASHMAN, WF STERN, AL AF GEDNEY, RT WRIGHT, DL BALOMBIN, JL SOHN, PY CASHMAN, WF STERN, AL TI ADVANCED COMMUNICATIONS TECHNOLOGY SATELLITE (ACTS) SO ACTA ASTRONAUTICA LA English DT Article AB The NASA Advanced Communications Technology Satellite (ACTS) provides high risk technologies having the potential to dramatically enhance the capabilities of the satellite communications industry. This experimental satellite, which will be launched by NASA in 1992, will furnish the technology necessary for providing a range of services. Utilizing the ACTS very high gain hopping spot beam antennas with on-board routing and processing, Very Small Aperture Terminal (VSAT) digital networks which provide on-demand, full mesh connectivity, 1. 544 Mbps services with only a single hop can be established. Each individual 64 kbps voice or data circuit from a VSAT is routed by the satellite to any location on the network. Secondly, the high pin spot beams make possible voice and data aeronautical communication in the large frequency bandwidth which exists at 30/20 GHz. The high gain spot beams also make feasible personal communications for low data rate services utilizing Ultra Small Aperture Terminals (USAT). Finally, the high gam spot beam antenna at Ka-band permits wide area, flexible networks providing 1 Gbps services between modest-size Earth terminals. This service is being considered in the U.S. for such applications as interconnecting supercomputers. This paper provides an overview of the ACTS and discusses the value of its technology for these communication applications including the spacecraft (S/C) weight per unit circuit for providing these services by ACTS technologies as compared to present-day satellites. For some of these services, the ACTS technologies may have more immediate application internationally rather than within the U.S. RP GEDNEY, RT (reprint author), NASA,LEWIS RES CTR,21000 BROOKPARK RD,MS 54-6,CLEVELAND,OH 44135, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD NOV PY 1992 VL 26 IS 11 BP 813 EP 825 DI 10.1016/0094-5765(92)90062-N PG 13 WC Engineering, Aerospace SC Engineering GA KD174 UT WOS:A1992KD17400006 ER PT J AU LEE, JE MARINARO, DE FUNKHOUSER, ME HORN, RM JEWETT, RP AF LEE, JE MARINARO, DE FUNKHOUSER, ME HORN, RM JEWETT, RP TI CREATING A COMMON MATERIALS DATABASE SO ADVANCED MATERIALS & PROCESSES LA English DT Article C1 PDA ENGN,COSTA MESA,CA. UNITED TECHNOL CORP,PRATT & WHITNEY,W PALM BEACH,FL. GENCORP INC,DIV AEROJET PROPULS,SACRAMENTO,CA. ROCKWELL INT CORP,DIV ROCKETDYNE,LOS ANGELES,CA. RP LEE, JE (reprint author), NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,HUNTSVILLE,AL 35812, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 SN 0026-0665 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD NOV PY 1992 VL 142 IS 5 BP 27 EP 33 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA JX688 UT WOS:A1992JX68800004 ER PT J AU TITRAN, RH AF TITRAN, RH TI NIOBIUM AND ITS ALLOYS SO ADVANCED MATERIALS & PROCESSES LA English DT Editorial Material RP TITRAN, RH (reprint author), NASA,LEWIS RES CTR,CLEVELAND,OH 44135, USA. NR 11 TC 11 Z9 12 U1 0 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 SN 0026-0665 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD NOV PY 1992 VL 142 IS 5 BP 34 EP & PG 0 WC Materials Science, Multidisciplinary SC Materials Science GA JX688 UT WOS:A1992JX68800005 ER PT J AU ERBLAND, PJ BOGUE, RK AF ERBLAND, PJ BOGUE, RK TI TAKING THE MEASURE OF AERODYNAMIC TESTING SO AEROSPACE AMERICA LA English DT Article C1 NASA,DRYDEN,ONTARIO,CANADA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0740-722X J9 AEROSPACE AM JI Aerosp. Am. PD NOV PY 1992 VL 30 IS 11 BP 16 EP & PG 0 WC Engineering, Aerospace SC Engineering GA JV035 UT WOS:A1992JV03500005 ER PT J AU MCKENZIE, RL HANSON, RK ECKBRETH, AC AF MCKENZIE, RL HANSON, RK ECKBRETH, AC TI SHEDDING NEW LIGHT ON GAS-DYNAMICS SO AEROSPACE AMERICA LA English DT Article RP MCKENZIE, RL (reprint author), NASA,AMES RES CTR,MOFFETT FIELD,CA 94035, USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0740-722X J9 AEROSPACE AM JI Aerosp. Am. PD NOV PY 1992 VL 30 IS 11 BP 20 EP 24 PG 5 WC Engineering, Aerospace SC Engineering GA JV035 UT WOS:A1992JV03500006 ER PT J AU GOLDIN, D AF GOLDIN, D TI EXPLORATION IS WIRED INTO OUR DNA SO AEROSPACE AMERICA LA English DT Article RP GOLDIN, D (reprint author), NASA,WASHINGTON,DC 20546, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0740-722X J9 AEROSPACE AM JI Aerosp. Am. PD NOV PY 1992 VL 30 IS 11 BP B36 EP B36 PG 1 WC Engineering, Aerospace SC Engineering GA JV035 UT WOS:A1992JV03500012 ER PT J AU FULLER, CR SNYDER, SD HANSEN, CH SILCOX, RJ AF FULLER, CR SNYDER, SD HANSEN, CH SILCOX, RJ TI ACTIVE CONTROL OF INTERIOR NOISE IN MODEL AIRCRAFT FUSELAGES USING PIEZOCERAMIC ACTUATORS SO AIAA JOURNAL LA English DT Article ID VIBRATION; REDUCTION AB Active control of interior noise in model aircraft fuselages using piezoceramic actuators is experimentally studied. The actuators are bonded directly to the structure and error information is taken from up to two microphones located in the interior acoustic field. The results demonstrate that global attenuation of the order of 10-15 dB of interior noise can be achieved with piezoceramic actuators, irrespective of whether the shell system is vibrating at an acoustic or structural resonant frequency. For the case of an acoustic resonance, reduction of the interior field was accompanied by an increase in shell response. The work also proves that active control using vibration (moment) inputs works well when a floor simulating that of an aircraft is installed in the model. This result suggests that the technique will be successful in controlling interior noise in realistic aircraft structures, although further work is needed to ensure that the approach works satisfactorily under realistic situations. C1 VIRGINIA POLYTECH INST & STATE UNIV,STRUCT ACOUST BRANCH,BLACKSBURG,VA 24061. UNIV ADELAIDE,ADELAIDE,SA 5001,AUSTRALIA. NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP FULLER, CR (reprint author), VIRGINIA POLYTECH INST & STATE UNIV,DEPT MECH ENGN,BLACKSBURG,VA 24061, USA. RI Hansen, Colin/A-8327-2008 OI Hansen, Colin/0000-0002-1444-4716 NR 9 TC 37 Z9 37 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD NOV PY 1992 VL 30 IS 11 BP 2613 EP 2617 DI 10.2514/3.11275 PG 5 WC Engineering, Aerospace SC Engineering GA JV780 UT WOS:A1992JV78000005 ER PT J AU MAESTRELLO, L FRENDI, A BROWN, DE AF MAESTRELLO, L FRENDI, A BROWN, DE TI NONLINEAR VIBRATION AND RADIATION FROM A PANEL WITH TRANSITION TO CHAOS SO AIAA JOURNAL LA English DT Article ID BOUNDARY; PLATE AB The dynamic response of an aircraft panel forced at resonance and off-resonance by plane acoustic waves at normal incidence is investigated experimentally and numerically. Linear, nonlinear (period doubling), and chaotic responses are obtained by increasing the sound pressure level of the excitation. The response time history is sensitive to the input level and to the frequency of excitation. The change in response behavior is due to a change in input conditions, triggered either naturally or by modulation of the bandwidth of the incident waves. Off-resonance bifurcation is diffused and difficult to maintain; thus the panel response drifts into a linear behavior. The acoustic pressure emanated by the panel is either linear or nonlinear as is the vibration response. The nonlinear effects accumulate during the propagation with distance. Results are also obtained on the control of the panel response using damping tape on an aluminum panel and a graphite epoxy panel having the same size and weight. Good agreement is obtained between the experimental and numerical results. C1 ANALYT SERV & MAT INC,HAMPTON,VA 23666. LOCKHEED ENGN & SCI CO,HAMPTON,VA 23666. RP MAESTRELLO, L (reprint author), NASA,LANGLEY RES CTR,HAMPTON,VA 23665, USA. NR 21 TC 25 Z9 26 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD NOV PY 1992 VL 30 IS 11 BP 2632 EP 2638 DI 10.2514/3.11278 PG 7 WC Engineering, Aerospace SC Engineering GA JV780 UT WOS:A1992JV78000008 ER PT J AU YOON, S KWAK, D AF YOON, S KWAK, D TI IMPLICIT NAVIER-STOKES SOLVER FOR 3-DIMENSIONAL COMPRESSIBLE FLOWS SO AIAA JOURNAL LA English DT Article ID EQUATIONS; SCHEME; EULER AB A three-dimensional numerical method based on the lower-upper symmetric-Gauss-Seidel implicit scheme in conjunction with the flux-limited dissipation model is developed for solving the compressible Navier-Stokes equations. A new computer code based on this method requires only 9 mus per grid point per iteration on a single processor of a Cray YMP computer and executes at the sustained rate of 175 MFLOPS. A reduction of three orders of magnitude in the residual for a high-Reynolds-number now using 636K grid points is obtained in 38 min. The computational results compare well with available experimental data. RP YOON, S (reprint author), NASA,AMES RES CTR,APPL COMPUTAT FLUIDS BRANCH,MS 202A-1,MOFFETT FIELD,CA 94035, USA. NR 42 TC 40 Z9 42 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD NOV PY 1992 VL 30 IS 11 BP 2653 EP 2659 DI 10.2514/3.48957 PG 7 WC Engineering, Aerospace SC Engineering GA JV780 UT WOS:A1992JV78000011 ER PT J AU COMPTON, WB ABDOLHAMID, KS ABEYOUNIS, WK AF COMPTON, WB ABDOLHAMID, KS ABEYOUNIS, WK TI COMPARISON OF ALGEBRAIC TURBULENCE MODELS FOR AFTERBODY FLOWS WITH JET EXHAUST SO AIAA JOURNAL LA English DT Article AB Three-dimensional Navier-Stokes simulations have been done for transonic and low supersonic flow past a nonaxisymmetric nozzle typical of those advocated for advanced fighter airplanes. The jet exhaust is included in the calculations. The investigation compares the performance of the unmodified Baldwin-Lomax turbulence model with its performance when enhanced by the Degani-Schiff and the Goldberg modifications. Solutions are presented for Mach numbers of 0.80, 0.94, and 1.20 at 0-deg angle of attack and a Reynolds number of 20 x 10(6). The numerical results, which are compared to the wind-tunnel data, show that the three turbulence models predict considerably different shock locations, separated-flow regions, and flowfields. C1 ANALYT SERV & MAT INC,HAMPTON,VA 23666. RP COMPTON, WB (reprint author), NASA,LANGLEY RES CTR,DIV APPL AERODYNAM,PROP AERODYNAM LAB,HAMPTON,VA 23665, USA. NR 22 TC 5 Z9 5 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD NOV PY 1992 VL 30 IS 11 BP 2716 EP 2722 DI 10.2514/3.11289 PG 7 WC Engineering, Aerospace SC Engineering GA JV780 UT WOS:A1992JV78000019 ER PT J AU WIELAND, TM MORTON, J STARNES, JH AF WIELAND, TM MORTON, J STARNES, JH TI SCALE EFFECTS IN BUCKLING, POSTBUCKLING, AND CRIPPLING OF GRAPHITE-EPOXY Z-SECTION STIFFENERS SO AIAA JOURNAL LA English DT Article AB The buckling, postbuckling, and crippling of graphite-epoxy Z-section stiffeners are investigated as functions of specimen structural parameters. Variables addressed are flange and web widths, flange-to-web corner radii, thickness, and stacking sequence. Analytical, numerical, and experimental results are discussed. Nondimensional parameters have been obtained from an analytical model which effectively normalize the initial local buckling data reported herein and in the literature. The nature of the load redistribution after buckling is related to the geometric variables. A normalized total width concept is used to unify the crippling data. Crippling mechanisms include flange-free edge delamination and local failure of the flange-to-web corner and are shown to depend upon the laminate stacking sequence. C1 NASA,LANGLEY RES CTR,DIV STRUCT MECH,AIRCRAFT STRUCT BRANCH,HAMPTON,VA 23665. RP WIELAND, TM (reprint author), VIRGINIA POLYTECH INST & STATE UNIV,DEPT ENGN SCI & MECH,BLACKSBURG,VA 24061, USA. NR 15 TC 0 Z9 0 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD NOV PY 1992 VL 30 IS 11 BP 2750 EP 2757 DI 10.2514/3.48961 PG 8 WC Engineering, Aerospace SC Engineering GA JV780 UT WOS:A1992JV78000024 ER PT J AU MORRISON, JH KORTE, JJ AF MORRISON, JH KORTE, JJ TI IMPLEMENTATION OF VIGNERON STREAMWISE PRESSURE-GRADIENT APPROXIMATION IN PARABOLIZED NAVIER-STOKES EQUATIONS SO AIAA JOURNAL LA English DT Note C1 NASA,LANGLEY RES CTR,DIV FLUID MECH,THEORET FLOW PHYS BRANCH,HAMPTON,VA 23665. RP MORRISON, JH (reprint author), ANALYT SERV & MAT INC,107 RES DR,HAMPTON,VA 23666, USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD NOV PY 1992 VL 30 IS 11 BP 2774 EP 2776 DI 10.2514/3.11297 PG 3 WC Engineering, Aerospace SC Engineering GA JV780 UT WOS:A1992JV78000027 ER PT J AU CARR, DH JENNINGS, DB THRASHER, TN KEIL, LC RAMSAY, DJ AF CARR, DH JENNINGS, DB THRASHER, TN KEIL, LC RAMSAY, DJ TI ROLE OF RIGHT HEART RECEPTORS IN THE CONTROL OF RENIN, VASOPRESSIN, AND CORTISOL SECRETION IN DOGS SO AMERICAN JOURNAL OF PHYSIOLOGY LA English DT Article DE BLOOD PRESSURE; RIGHT ATRIAL RECEPTORS; LEFT ATRIAL RECEPTORS; ATRIAL NATRIURETIC FACTOR; ANTIDIURETIC HORMONE; ADRENOCORTICOTROPIC HORMONE; PLASMA RENIN ACTIVITY; ARGININE VASOPRESSIN ID ATRIAL NATRIURETIC FACTOR; CONSCIOUS DOGS; ARTERIAL-HYPOTENSION; PLASMA VASOPRESSIN; RELEASE; PRESSURE; SUPPRESSION; INHIBITION; PEPTIDES; STRETCH AB We have reported that increased left heart pressure inhibits increases in plasma renin activity (PRA), arginine vasopressin (AVP), and cortisol during arterial hypotension. The goal of this study was to determine whether increases in right heart pressure also inhibited hormonal responses to hypotension. Seven dogs were chronically instrumented with inflatable cuffs around the ascending aorta (AA), the pulmonary artery (PA), and the thoracic inferior vena cava (IVC), as well as with catheters in both atria, the abdominal aorta, and vena cava. The IVC, the PA, and the AA cuffs were inflated on different days to cause step reductions in mean arterial pressure (MAP) of 5, 10, 20, and 30% below control MAP. Graded constriction of the AA caused large increases in left atrial pressure and plasma atrial natriuretic peptide (ANP), but had no effect on plasma AVP or cortisol and caused only a small increase in PRA at the maximal reduction of MAP. Constriction of the IVC reduced both atrial pressures and plasma ANP, but stimulated increases in PRA, AVP, and cortisol. Constriction of the PA increased right atrial pressure and plasma ANP and caused increases in plasma AVP and cortisol that were similar to responses during IVC constriction, but the PRA response was only half (P < 0.05). These results indicate that increasing pressure on the right side of the heart can attenuate the PRA response to hypotension, and suggest that the inhibition is mediated by the rise in plasma ANP. C1 UNIV CALIF SAN FRANCISCO,SCH MED,DEPT PHYSIOL,SAN FRANCISCO,CA 94143. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 26 TC 16 Z9 16 U1 1 U2 3 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0002-9513 J9 AM J PHYSIOL JI Am. J. Physiol. PD NOV PY 1992 VL 263 IS 5 BP R1071 EP R1077 PN 2 PG 7 WC Physiology SC Physiology GA JZ779 UT WOS:A1992JZ77900055 ER PT J AU HARDMAN, P SPOONER, BS AF HARDMAN, P SPOONER, BS TI LOCALIZATION OF EXTRACELLULAR-MATRIX COMPONENTS IN DEVELOPING MOUSE SALIVARY-GLANDS BY CONFOCAL MICROSCOPY SO ANATOMICAL RECORD LA English DT Article DE EXTRACELLULAR MATRIX; CONFOCAL MICROSCOPY; MORPHOGENESIS; SUBMANDIBULAR GLAND; MOUSE ID LUNG BRANCHING MORPHOGENESIS; BASAL LAMINA; SUBMANDIBULAR-GLAND; COLLAGEN-III; GLYCOSAMINOGLYCAN; ACCUMULATION; EPITHELIUM; DEPOSITION; MEMBRANE; SURFACE AB The importance of the extracellular matrix (ECM) in epithelial-mesenchymal interactions in developing organisms is well established. Proteoglycans and interstitial collagens are required for the growth, morphogenesis, and differentiation of epithelial organs and the distribution of these molecules has been described. However, much less is known about other ECM macromolecules in developing epithelial organs. We used confocal microscopy to examine the distribution of laminin, heparan sulfate (BM-1) proteoglycan, fibronectin, and collagen types I, IV, and V, in mouse embryonic salivary glands. Organ rudiments were isolated from gestational day 13 mouse embryos and cultured for 24, 48, or 72 hours. Whole mounts were stained by indirect immunofluorescence and then examined using a Zeiss Laser Scan Microscope. We found that each ECM component examined had a distinct distribution and that the distribution of some molecules varied with culture time. Laminin was mainly restricted to the basement membrane. BM-1 proteoglycan was concentrated in the basement membrane and also formed a fine network throughout the mesenchyme. Type IV collagen was mainly located in the basement membrane of the epithelium, but it was also present throughout the mesenchyme. Type V collagen was distributed throughout the mesenchyme at 24 hours, but at 48 hours was principally located in the basement membrane. Type I collagen was distributed throughout the mesenchyme at all culture times, and accumulated in the clefts and particularly at the epithelial-mesenchymal interface as time in culture increased. Fibronectin was observed throughout the mesenchyme at all times. RP HARDMAN, P (reprint author), KANSAS STATE UNIV AGR & APPL SCI,DIV BIOL,NASA,SPECIALIZED CTR RES & TRAINING,MANHATTAN,KS 66506, USA. NR 25 TC 24 Z9 25 U1 0 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0003-276X J9 ANAT REC JI Anat. Rec. PD NOV PY 1992 VL 234 IS 3 BP 452 EP 459 DI 10.1002/ar.1092340315 PG 8 WC Anatomy & Morphology SC Anatomy & Morphology GA JU551 UT WOS:A1992JU55100014 PM 1443671 ER PT J AU LEE, RB AVIS, LM GIBSON, MA KOPIA, LP AF LEE, RB AVIS, LM GIBSON, MA KOPIA, LP TI CHARACTERIZATIONS OF THE MIRROR ATTENUATOR MOSAIC - SOLAR DIFFUSER PLATE SO APPLIED OPTICS LA English DT Article DE RADIOMETRY; SOLAR DIFFUSER; THERMISTOR BOLOMETER ID RADIATION AB The mirror attenuator mosaic (MAM), a solar diffuser plate, was used for the flight calibration of the broadband shortwave (0.2-5-mum) and total (0.2 to > 200-mum) Earth Radiation Budget Experiment scanning thermistor bolometer radiometers. The MAM solar-reflecting surface cosisted of a tightly packed array of vacuum-deposited aluminum, concave spherical mirrors, while its solar-absorbing surface consisted of black chrome. The effective reflectance of the MAM was constant to within +/-2% after almost 2 years in orbit, a marked improvement over earlier solar diffusers. C1 SCI APPLICAT INT CORP,HAMPTON,VA 23666. RP LEE, RB (reprint author), NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,HAMPTON,VA 23665, USA. NR 22 TC 22 Z9 22 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD NOV 1 PY 1992 VL 31 IS 31 BP 6643 EP 6652 PG 10 WC Optics SC Optics GA JW127 UT WOS:A1992JW12700015 PM 20733891 ER PT J AU COHEN, M WALKER, RG WITTEBORN, FC AF COHEN, M WALKER, RG WITTEBORN, FC TI SPECTRAL IRRADIANCE CALIBRATION IN THE INFRARED .2. ALPHA-TAU AND THE RECALIBRATION OF THE IRAS LOW RESOLUTION SPECTROMETER SO ASTRONOMICAL JOURNAL LA English DT Article ID TEMPERATURE SCALE; SPECTROPHOTOMETRY; SYSTEM; STARS AB We describe a general technique for assembling continuous calibrated infrared spectra over a wide wavelength range. To demonstrate the method we construct an absolutely calibrated 1-35 mum spectrum of alpha Tau and independently validate the method using new and carefully designed observations. First we investigate the absolute calibration of the IRAS low resolution spectrometer (LRS) database by comparing this observed spectrum of alpha Tau with that assumed in the original LRS calibration scheme. Second, an analysis of asteroidal LRS spectra results in an independent assessment of the calibration problems with the LRS and provides a natural complement to the effort based on alpha Tau. Stellar studies define the short wavelength problems well; the cool asteroids characterize the long wavelengths. Third, we make a direct comparison of LRS stellar spectra with independently calibrated long-wavelength (approximately 20 mum) airborne and ground-based spectra. These three approaches are complementary and have been combined. Neglect of the SiO fundamental band in alpha Tau has led to the presence of a specious "emission" feature in all LRS spectra near 8.5 mum, and to an incorrect spectral slope between 8 and approximately 12 mum. We explain the differences between this new LRS recalibration and that due to Volk & Cohen [AJ, 98, 1918 (1989)] and discuss why the present set of "correction factors" is more accurate. Recognition of the influence of the SiO fundamental on both the LRS calibration and on the continua of cool normal giant stars also leads to an understanding of the apparent plethora of classes into which these normal stars fall when assigned by the AUTOCLASS (Cheeseman et al. 1989) artificial intelligence scheme applied to the IRAS LRS Atlas. C1 UNIV CALIF BERKELEY,RADIO ASTRON LAB,BERKELEY,CA 94720. NASA,AMES RES CTR,ASTROPHYS BRANCH,MOFFETT FIELD,CA 94035. RP COHEN, M (reprint author), JAMIESON SCI & ENGN INC,5321 SCOTTS VALLEY DR,SUITE 204,SCOTTS VALLEY,CA 95066, USA. NR 32 TC 123 Z9 124 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 1992 VL 104 IS 5 BP 2030 EP 2044 DI 10.1086/116379 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV270 UT WOS:A1992JV27000028 ER PT J AU COHEN, M WITTEBORN, FC CARBON, DF AUGASON, G WOODEN, D BREGMAN, J GOORVITCH, D AF COHEN, M WITTEBORN, FC CARBON, DF AUGASON, G WOODEN, D BREGMAN, J GOORVITCH, D TI SPECTRAL IRRADIANCE CALIBRATION IN THE INFRARED .3. THE INFLUENCE OF CO AND SIO SO ASTRONOMICAL JOURNAL LA English DT Article ID CHEMICAL-COMPOSITION; RED GIANTS; EMISSION FEATURES; SILICON MONOXIDE; HIGH-RESOLUTION; FLUX METHOD; G-STAR; BANDS; SPECTROSCOPY; TEMPERATURE AB We describe first efforts to establish a network of calibrated infrared spectra of "standard stars" suitable for calibration of at least low-resolution infrared spectrometers using ground-based, airborne, and satellite-borne broadband sensors. The focus of this paper is on the crucial 5-8 mum region, inaccessible from the ground, in K and M giants. In this region the fundamental bands of CO and SiO cause substantial departures from featureless pseudo-continua. These departures are, of course, well-known to stellar atmosphere theorists. However, they are still ignored by many astronomical infrared photometrists and spectroscopists who assume that these bright stars can be represented by blackbodies at their effective temperatures. The purpose of this short paper is to draw the attention of infrared observers in the field to the invalidity of the blackbody assumption in the thermal infrared regime. We hope to achieve this end by observationally demonstrating the importance of these molecular features in cool giant stars in the airborne infrared regime, and illustrating their influence on spectra that are calibrated using blackbody assumptions. To help confirm our identifications of the principal molecular features, we present a synthetic spectrum computed using a model atmosphere with the approximate parameters of alpha Tau. This theoretical synthetic spectrum, which contains line opacity only from CO and SiO, reproduces the observed spectrum of alpha Tau to within a few percent. C1 NASA,AMES RES CTR,ASTROPHYS BRANCH,MOFFETT FIELD,CA 94035. NASA,AMES RES CTR,NAS SYST DEV BRANCH,MOFFETT FIELD,CA 94035. NASA,AMES RES CTR,SPACE INSTRUMENTAT & STUDIES BRANCH,MOFFETT FIELD,CA 94035. RP COHEN, M (reprint author), UNIV CALIF BERKELEY,RADIO ASTRON LAB,601 CAMPBELL HALL,BERKELEY,CA 94720, USA. NR 45 TC 50 Z9 50 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 1992 VL 104 IS 5 BP 2045 EP 2052 DI 10.1086/116380 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV270 UT WOS:A1992JV27000029 ER PT J AU SAUVAL, AJ FARRENQ, R GUELACHVILI, G GREVESSE, N FARMER, CB NORTON, RH AF SAUVAL, AJ FARRENQ, R GUELACHVILI, G GREVESSE, N FARMER, CB NORTON, RH TI ON THE ACCURACY OF CO LINE POSITIONS FOR HIGH-RESOLUTION IR STELLAR SPECTROSCOPY SO ASTRONOMY & ASTROPHYSICS LA English DT Note DE ATOMIC AND MOLECULAR DATA; CARBON MONOXIDE; SPECTROSCOPY; LINES, IDENTIFICATION; STARS, ATMOSPHERES OF; SUN (THE), PHOTOSPHERE OF ID HETERODYNE FREQUENCY MEASUREMENTS; (CO)-C-12-O-16 LASER TRANSITIONS; DUNHAM COEFFICIENTS; GROUND-STATE; MOLECULAR-CONSTANTS; INFRARED-SPECTRA; STARS; CARBON; OXYGEN AB We show the high accuracy of line positions derived from our improved sets of Dunham coefficients for the four more abundant isotopic species of carbon monoxide ((CO)-C-12-O-16), (CO)-C-13-O-16, (CO)-C-12-O-17) which are present in the sun and in cool stellar atmospheres. These new spectroscopic constants allow to predict very accurate positions of CO lines at any J-values, especially at very high rotational excitation (up to J around 135). We have checked earlier proposed identifications of CO lines at large J-values and we found some incorrect identifications in sunspot spectra. Our accurate line positions have also been compared with predictions from other available sets of molecular constants. We conclude that our improved sets of molecular constants are the most appropriate to all problems of high resolution stellar and solar spectroscopy at any J- and v-values (with J(max) = 133 and v(max) = 41), particularly for synthetic spectra of cool stars. C1 UNIV PARIS 11, PHYS MOLEC & APPL LAB, CNRS, F-91405 ORSAY, FRANCE. UNIV LIEGE, INST ASTROPHYS, B-4000 COINTE OUGREE, BELGIUM. JET PROP LAB, PASADENA, CA 91109 USA. RP SAUVAL, AJ (reprint author), OBSERV ROYAL BELGIQUE, AVE CIRCULAIRE 3, B-1180 BRUSSELS, BELGIUM. NR 37 TC 8 Z9 8 U1 0 U2 3 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD NOV PY 1992 VL 265 IS 1 BP 355 EP 359 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX135 UT WOS:A1992JX13500039 ER PT J AU Esposito, JA Christian, ER Balasubrahmanyan, VK Barbier, LM Ormes, JF Streitmatter, RE Acharya, B Luzietti, B Hesse, A Heinbach, U Heinrich, W Henkel, M Pfeifer, C Simon, M AF Esposito, J. A. Christian, E. R. Balasubrahmanyan, V. K. Barbier, L. M. Ormes, J. F. Streitmatter, R. E. Acharya, B. Luzietti, B. Hesse, A. Heinbach, U. Heinrich, W. Henkel, M. Pfeifer, C. Simon, M. TI The ALICE instrument and the measured cosmic ray elemental abundances SO ASTROPARTICLE PHYSICS LA English DT Article AB A Large Isotopic Composition Experiment (ALICE) is a balloon-borne spectrometer which can determine the elemental and isotopic composition of galactic cosmic rays with energies near 1 GeV/nucleon. ALICE was flown from Prince Albert, Canada in August 1987, and remained at float altitude (120 000 feet) for 14.7 hours. In this paper, we describe the experimental methods and analysis which will be used for subsequent isotopic analysis. We obtained very precise charge resolution over the entire designed range: 0.10 and 0.16 charge units at neon and iron, respectively. Results on the galactic cosmic ray abundances and absolute fluxes of the elements from neon through nickel are reported. C1 [Esposito, J. A.; Christian, E. R.; Balasubrahmanyan, V. K.; Barbier, L. M.; Ormes, J. F.; Streitmatter, R. E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Acharya, B.; Luzietti, B.; Hesse, A.; Heinbach, U.; Heinrich, W.; Henkel, M.; Pfeifer, C.; Simon, M.] Univ Siegen, Siegen, Germany. [Esposito, J. A.] Univ Deleware, Bartol Res Inst, Newark, DE 19716 USA. [Acharya, B.] TATA Inst, Bombay, Maharashtra, India. RP Christian, ER (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. FU NASA; Deutsche Forschungsgemeinschaft (DFG); NATO [N 0325/84] FX We gratefully acknowledge the support of this project by the NASA Supporting Research and Technology program (SR & T) and the Deutsche Forschungsgemeinschaft (DFG).; Also thanks to a NATO grant N 0325/84 which covered part of our travel expences. We are grateful to R. Greer, T. Laws, G. Latsch, K. Schmeck and D. Righter, without whose dedicated technical and engineering support the ALICE experiment could not have been done. We thank the personnel of the National Scientific Ballon Facility (NSBF) for their professionalism in carrying out our flight and K. Hazelwood in particular for having a highly sucessful campaign in difficult circumstances. NR 15 TC 11 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-6505 J9 ASTROPART PHYS JI Astropart Phys. PD NOV PY 1992 VL 1 IS 1 BP 33 EP 45 DI 10.1016/0927-6505(92)90007-M PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA V26DJ UT WOS:000208526000005 ER PT J AU TURNER, BE CHAN, KW GREEN, S LUBOWICH, DA AF TURNER, BE CHAN, KW GREEN, S LUBOWICH, DA TI TESTS OF SHOCK CHEMISTRY IN IC 443G SO ASTROPHYSICAL JOURNAL LA English DT Article DE H-II REGIONS; ISM, INDIVIDUAL (IC 443); ISM, MOLECULES; MOLECULAR PROCESSES; SHOCK WAVES ID DENSE INTERSTELLAR CLOUDS; INTER-STELLAR SHOCKS; ROTATIONAL-EXCITATION; COLLISIONAL EXCITATION; MOLECULAR COMPOSITION; REMNANT IC-443; GAS; EMISSION; SIO; CO AB A multitransition single-dish study has been made of the molecular species CO, HCO+, HCN, CN, SiO, CS, SO, and H2CO toward the "shocked" clump IC 443G associated with the supernova remnant IC 443. Maps of each molecule show source sizes less-than-or-equal-to 40" and essentially uniform brightness. A BIMA interferometer map of the 1-0 transition of HCO' shows four small clumps, whose combined flux is only 4.5% of the single-dish flux, so that they represent only small enhancements of an otherwise smooth distribution. A BIMA map of the 86 GHz transition of SO detected no emission to a level of 0.518 Jy beam-1, indicating no clumping on size scales up to 21", the beamwidth of the single-dish observations. The observations have been analyzed by both large velocity gradient and microturbulent radiative transfer models, from which densities, temperatures, and abundances are inferred. These models used collision rates calculated in detail for every species except CN and SO, including new collision rates calculated for SiO at low temperatures (40-300 K) and for CS at higher temperatures (100-300 K) than previously existed. We find that the eight species may be divided into two groups. Group 1 species (CO, HCO', HCN, CN) arise in region 1 with density n approximately (2-8) x 1O(5) cm-3, temperature T less-than-or-equal-to 100 K, and linear extent L almost-equal-to 7 x 10(17) cm, While group 2 species (SiO, CS, SO, H2CO) arise in the hotter (T = 200-300 K), denser (n greater-than-or-equal-to 10(6) cm-3) region 2 with smaller L. While abundances of group 1 species are consistent with ion-molecule chemistry, the observed abundances of group 2 species, if they are coextensive with group 1 species, are much lower than predicted ion-molecule abundances, and in addition the observed line widths are all much larger than those of quiescent clouds where ion-molecule processes are believed to dominate. We find that dissociative (D) shock models of Neufeld & Dalgarno (1989) agree well with observed abundances of group 1 species, while nondissociative (ND) shock models (Mitchell 1984a, b; Hartquist, Oppenheimer, & Dalgarno 1980) explain group 2 abundances well. Specifically, both observations and D shock models show that abundances of group 1 species are in no cases enhanced by shocks over quiescent cloud conditions, while both observations and ND shock models show that abundances of group 2 species are all reduced below quiescent cloud (ion-molecule) abundances as a result of shocks unless they occupy a region approximately 100 times smaller than group 1 species, in which case their fractional abundances are similar to those of ion-molecule chemistry. In general, observed line widths vary inversely with derived excitation density, while centroid velocities of all species are essentially identical. This requires that the shock velocity v, in the clump varies along the path z, rising quasi-symmetrically from a small value at z = 0 (rear face of the clump) to a maximum value in region 1, then decreasing to a value consistent with a ND shock in region 2 (near face of clump). The density gradient necessary to produce the upsilon(c), function must have preceded the shock. All physical and chemical properties can be explained satisfactorily on this picture of the IC 443G clump, but it is ad hoc, and more detailed models of shocks in nonhomogeneous media are needed. C1 UNIV MARYLAND,DEPT ASTRON,COLL PK,MD 20742. NASA,GODDARD SPACE FLIGHT CTR,INST SPACE STUDIES,NEW YORK,NY 10025. HOFSTRA UNIV,DEPT PHYS & ASTRON,HEMPSTEAD,NY 11550. AMER INST PHYS,WOODBURY,NY 11797. RP TURNER, BE (reprint author), NATL RADIO ASTRON OBSERV,520 EDGEMONT RD,CHARLOTTESVILLE,VA 22903, USA. NR 44 TC 124 Z9 124 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP 114 EP 133 DI 10.1086/171908 PN 1 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV047 UT WOS:A1992JV04700013 ER PT J AU ALLAMANDOLA, LJ SANDFORD, SA TIELENS, AGGM HERBST, TM AF ALLAMANDOLA, LJ SANDFORD, SA TIELENS, AGGM HERBST, TM TI INFRARED-SPECTROSCOPY OF DENSE CLOUDS IN THE C-H STRETCH REGION - METHANOL AND DIAMONDS SO ASTROPHYSICAL JOURNAL LA English DT Article DE H-II REGIONS; INFRARED, INTERSTELLAR, LINES; ISM, MOLECULES; LINE, IDENTIFICATION ID TIME-DEPENDENT CHEMISTRY; MOLECULAR CLOUDS; INTERSTELLAR DIAMONDS; ABSORPTION FEATURES; ICE-BAND; SOLID METHANOL; MICRON SPECTRA; PROTOSTARS; CONSTRAINTS; ORIGIN AB High spectral resolution (v/DELTAv = 900) studies in the 3100-2600 cm-1 (3.2-3.9 mum) range are presented of the protostars NGC 7538 IRS 9, W33A, W3 IRS 5, and S140 IRS 1. This is the spectral region in which the fundamental C-H stretching vibrations of aliphatic hydrocarbons fall. Well-resolved absorption bands at about 2825 cm-1 (3.54 mum) and 2880 cm-1 (3.47 mum) were found superposed on the low-frequency wing of the strong O-H stretch feature. The 2880 cm-1 (3.47 mum) band, a new interstellar feature, is moderately strong in the spectra of all four objects studied. The 2825 cm-1 (3.54 mum) band, previously detected toward W33A, is also in the spectrum of NGC 7538 IRS 9. The relative strength of these two bands varies, showing that they are associated with two different carriers. On the basis of comparisons with laboratory spectra, the 2825 cm-1 (3.54 mum) band is assigned to methanol (CH3OH), in agreement with the earlier work of Grim et al. (1991). This assignment is further supported by a pair of weak absorptions centered at 2600 and 2540 cm-1 (3.85 and 3.94 mum) in the spectrum of W33A recently reported by Geballe (1991). These features compare very well with laboratory spectra of CH3OH/H2O ice mixtures. The CH3OH/H2O ratio derived from the 2825 cm-1 methanol band and the 3250 cm-1 (3.08 mum) H2O feature are 0.13 and 0.40 for NGC 7538 IRS 9 and W33A, respectively. These values are smaller than the ratios of 0.61 and 0.54 derived using the 1460 cm-1 (6.85 mum) band assigned to CH3OH and the 1665 cm-1 (6.00 mum) H2O band. These apparent discrepancies may be due to a combination of scattering effects within the molecular cloud, uncertainties associated with the baselines for the 2825 cm-1 feature, and the presence of other interstellar grain materials that absorb at 1460 cm-1 (6.85 mum). Nonetheless, after H2O, CH3OH is the most abundant known interstellar ice constituent. The new band at about 2880 cm-1 (3.47 mum) falls near the position for C-H stretching vibrations in tertiary carbon atoms (CH). The strength of this feature, in combination with the lack of strong features associated with primary (-CH3) and secondary (-CH2-) carbon atoms, suggests that the carrier of the new feature has a diamond-like structure. We therefore tentatively attribute this new feature to interstellar "diamonds." The detection of this band in the spectra of all four dense molecular clouds suggests that the carrier is ubiquitous in dense clouds. Band-strength analysis indicates that a minimum of a few percent of the available cosmic carbon is tied up in this material. C1 NASA,AMES RES CTR,MT VIEW,CA 94035. UNIV HAWAII,INST ASTRON,HONOLULU,HI 96822. NR 56 TC 255 Z9 255 U1 1 U2 16 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP 134 EP 146 DI 10.1086/171909 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV047 UT WOS:A1992JV04700014 PM 11540063 ER PT J AU KORYCANSKY, DG AF KORYCANSKY, DG TI GROWTH AND DECAY OF DISTURBANCES IN STRATIFIED SHEAR-FLOW IN A ROTATING FRAME SO ASTROPHYSICAL JOURNAL LA English DT Article DE HYDRODYNAMICS; INSTABILITIES ID PRIMORDIAL SOLAR NEBULA; PLANE COUETTE-FLOW; EVOLUTION; STABILITY; MODES; DISKS AB We have investigated the stability of stratified plane Couette flow in a rotating frame, for a case in which the gravitational force is parallel to the rotation vector. Such a flow is a local approximation to the basic flow of an accretion disk. The gravity and Brunt-Vaisala frequency are taken to be constant, and viscosity and heat diffusion are included. We derive partial differential equations describing the behavior of disturbances in the linear regime, which we reduced to time-dependent ordinary differential equations by means of the "shearing-sheet" transformation introduced by Goldreich & Lynden-Bell. We have looked at several different cases and investigated the asymptotic (long-time) behavior. Unstratified flow is stable as long as the angular momentum gradient is positive (Rayleigh's criterion). If the gradient is negative, nonaxisymmetric disturbances grow as a power law in time, if the gradient is sufficiently steep. In flow which is unstable to convection, all perturbations asymptotically grow at the rate given by the Brunt-Vaisala frequency. If heat diffusion is included, all nonaxisymmetric perturbations now eventually decay as t-2, even if the flow is unstable to convection. If viscosity is included, nonaxisymmetric perturbations asymptotically decay as t-2 exp (-4A2m2vt3/3), where A is the value of the shear gradient, m is the longitudinal wavenumber, and v is the viscosity. If heat diffusion and viscosity are weak, nonaxisymmetric disturbances in convectively unstable flow will undergo a large transient growth before their eventual deca RP KORYCANSKY, DG (reprint author), NASA,AMES RES CTR,DIV SPACE SCI,MOFFETT FIELD,CA 94035, USA. NR 21 TC 12 Z9 12 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP 176 EP 181 DI 10.1086/171913 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV047 UT WOS:A1992JV04700018 ER PT J AU MILLER, JA STEINACKER, J AF MILLER, JA STEINACKER, J TI STOCHASTIC GYRORESONANT ELECTRON ACCELERATION IN A LOW-BETA PLASMA .2. IMPLICATIONS OF THERMAL EFFECTS IN A SOLAR-FLARE PLASMA SO ASTROPHYSICAL JOURNAL LA English DT Article DE ACCELERATION OF PARTICLES; MHD; PLASMAS; SUN, FLARES; SUN, PARTICLE EMISSION ID PROTON-BEAM GENERATION; LOW-FREQUENCY WAVES; X-RAY BURSTS; ENERGETIC PARTICLES; WHISTLER WAVES; CORONA; INSTABILITIES; SCATTERING; EXCITATION; MODE AB We consider the thermal damping of R and L waves under typical solar flare conditions. These waves were previously employed in Paper I to stochastically accelerate electrons to relativistic energies in impulsive events. We find that the thermal particles cause rapid dissipation of the cyclotron waves, but do not affect whistlers and Alfven waves. The dissipation of electron cyclotron waves in particular leads to a threshold energy for acceleration which is about 10 times the thermal energy. Therefore, in the absence of an instability that excites these high-frequency waves, a second mechanism is required in order to inject a sufficient number of electrons above the threshold energy and account for solar flare gamma-ray bremsstrahlung emission. We also find that the comoving gyroresonance, which occurs when the electron is in gyroresonance with an R wave whose group velocity equals the parallel electron velocity, can be realized by relativistic electrons if the plasma temperature is less than or similar to 5 x 10(6) K. RP MILLER, JA (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,CODE 665,GREENBELT,MD 20771, USA. NR 42 TC 24 Z9 24 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP 284 EP 293 DI 10.1086/171923 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV047 UT WOS:A1992JV04700028 ER PT J AU CHARNLEY, SB TIELENS, AGGM MILLAR, TJ AF CHARNLEY, SB TIELENS, AGGM MILLAR, TJ TI ON THE MOLECULAR COMPLEXITY OF THE HOT CORES IN ORION-A - GRAIN SURFACE-CHEMISTRY AS THE LAST REFUGE OF THE SCOUNDREL SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM, ABUNDANCES; ISM, CLOUDS; ISM, MOLECULES; MOLECULAR PROCESSES ID CN RADICAL REACTIONS; INTERSTELLAR CLOUDS; CHEMICAL-MODELS; SOLID METHANOL; LINE SURVEY; FORMALDEHYDE; TEMPERATURE; ABUNDANCES; DISCOVERY; STARS AB We have modeled the gas phase chemistry of warm molecular material around protostars that is seeded with evaporating grain mantles. We show that the release of simple molecules into the gas drives ion-molecule and neutral chemistries which can account for many of the complex 0-bearing and N-bearing molecules observed in hot cores. Initial grain mantle components and secondary product molecules are identified, and the observational consequences are discussed. C1 UNIV MANCHESTER,INST SCI & TECHNOL,DEPT MATH,MANCHESTER M60 1QD,LANCS,ENGLAND. RP CHARNLEY, SB (reprint author), NASA,AMES RES CTR,DIV SPACE SCI,MS 245-3,MOFFETT FIELD,CA 94035, USA. RI Charnley, Steven/C-9538-2012 NR 40 TC 191 Z9 191 U1 0 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP L71 EP L74 DI 10.1086/186609 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV048 UT WOS:A1992JV04800019 ER PT J AU EISENHARDT, P DICKINSON, M AF EISENHARDT, P DICKINSON, M TI HOW OLD IS THE Z=3.4 RADIO GALAXY B2-0902+34 SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, EVOLUTION; GALAXIES, FORMATION; GALAXIES, PHOTOMETRY; RADIO CONTINUUM, GALAXIES ID REDSHIFT; DISCOVERY AB We have observed the redshift 3.395 radio galaxy B2 0902 + 34 at K and in a 0.09 mum wide 2.21 mum filter which includes the redshifted [O III] 4959 and 5007 angstrom emission lines. We find m(K) = 19.9 +/- 0.3 in a 4" aperture, a magnitude fainter than Lilly's (1988) value, while the narrow-band image reveals that most of this flux is actually due to line emission. After correcting for [O III], we find continuum values m(K) = 21.5-1.1 +infinity, and R-K = 1.9 -infinity(+1.1). This color is consistent with the flat F(nu) spectrum considered characteristic of a protogalaxy. Differences between the K and [O III] morphologies suggest that some K continuum flux is present in addition to the [O III] emission. Our data may indicate the presence of an extended (greater than or similar to 10" diameter) halo at K. This halo, if real, makes the line-free continuum brighter (20.0-0.4(+0.7)) and redder (3.4-0.7(+0.4)). The halo is not caused by [O III] emission and may be a systematic error in the K data. However, it would be consistent with the brighter M(K) values measured by Lilly in larger apertures using a single element photometer. In any case, ages derived from stellar population models based on the limit R - K < 3.8 are much younger than those for the I - K = 4.5 value reported by Lilly. C1 UNIV CALIF BERKELEY,DEPT ASTRON,BERKELEY,CA 94720. RP EISENHARDT, P (reprint author), JET PROP LAB,MS 169-506,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 20 TC 42 Z9 42 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP L47 EP L50 DI 10.1086/186603 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV048 UT WOS:A1992JV04800013 ER PT J AU KASHLINSKY, A AF KASHLINSKY, A TI LATEST COBE RESULTS, LARGE-SCALE DATA, AND PREDICTIONS OF INFLATION SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMOLOGY, THEORY; COSMIC MICROWAVE BACKGROUND; LARGE-SCALE STRUCTURE OF UNIVERSE; GALAXIES, FORMATION ID MICROWAVE BACKGROUND ANISOTROPIES; GALAXY CORRELATIONS; UNIVERSE AB We use the nonscaled data from the APM catalog and the data on peculiar velocities to compute the microwave background radiation (MBR) anisotropy parameters on the assumption of the standard inflationary model: OMEGA = 1 and the Harrison-Zeldovich (HZ) power spectrum on large scales. To reduce the uncertain effects of possible galaxy evolution and rescaling the APM data is used in 6 narrow magnitude range, DELTAm congruent-to 0.5, in order to compute the maximal wavenumber, k0, where the power spectrum can enter the HZ regime. (The scale k0-1 we find from the APM data exceeds the horison scale at the matter-radiation equality beyond which the initial spectrum is not expected to be modified for conventional evolution models.) The peculiar velocity data are then applied to constrain the value of the bias parameter, b; this allows us to calculate MBR anisotropies independently of the assumptions on b. The numbers for the quadrupole anisotropy, Q, and the smoothed MBR correlation amplitude, [C-10-degrees(0)]1/2, we obtain are consistent within the error bars with the COBE results and can then be interpreted as supporting the standard inflationary picture. We emphasize at the same time that inflation would be inconsistent with the COBE results and the large-scale structure data if either the transition to the HZ regime is less sharp than assumed here or if more power is found on scales that currently cannot be probed by galaxy samples. Furthermore, we show that it would be hard to explain the results from smaller scale experiments, most notably the UCSB one with FWHM = 1-degrees., if inflationary paradigm is combined with APM data and the COBE results. RP KASHLINSKY, A (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 685,GREENBELT,MD 20771, USA. NR 25 TC 17 Z9 17 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP L1 EP L4 DI 10.1086/186591 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV048 UT WOS:A1992JV04800001 ER PT J AU MORRIS, M DAVIDSON, JA WERNER, M DOTSON, J FIGER, DF HILDEBRAND, R NOVAK, G PLATT, S AF MORRIS, M DAVIDSON, JA WERNER, M DOTSON, J FIGER, DF HILDEBRAND, R NOVAK, G PLATT, S TI POLARIZATION OF THE FAR-INFRARED EMISSION FROM THE THERMAL FILAMENTS OF THE GALACTIC-CENTER ARC SO ASTROPHYSICAL JOURNAL LA English DT Article DE DUST, EXTINCTION; GALAXY, CENTER; INFRARED, INTERSTELLAR, CONTINUUM; ISM, MAGNETIC FIELDS; POLARIZATION ID MAGNETIC-FIELD; CENTER REGION; RADIO ARC; LINE; MODEL AB The polarization of the 100 mum continuum emission has been measured at 14 positions in the dense, warm molecular cloud associated with the arched filaments, or the "bridge," of the radio arc near the Galactic center. At all positions the percent polarization is found to be quite large, ranging up to 6.5%. The polarization is interpreted in terms of thermal emission by magnetically aligned dust grains. The directions of the polarization vectors then indicate that the magnetic field is (1) parallel to the long dimension of the thermal radio filaments, and (2) very uniform on scales of 1-10 pc. Of several explanations for the inferred field geometry, the simplest is that it results from the unusually large dynamical shear in the emitting cloud. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. JET PROP LAB,PASADENA,CA 91109. UNIV CHICAGO,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. UNIV CHICAGO,DEPT PHYS,CHICAGO,IL 60637. UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637. PRINCETON UNIV,DEPT PHYS,PRINCETON,NJ 08544. RP MORRIS, M (reprint author), UNIV CALIF LOS ANGELES,DEPT ASTRON,8979 MATH SCI BLDG,LOS ANGELES,CA 90024, USA. NR 32 TC 30 Z9 30 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP L63 EP L66 DI 10.1086/186607 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV048 UT WOS:A1992JV04800017 ER PT J AU SKINNER, CJ TIELENS, AGGM BARLOW, MJ JUSTTANONT, K AF SKINNER, CJ TIELENS, AGGM BARLOW, MJ JUSTTANONT, K TI METHANOL ICE IN THE PROTOSTAR GL-2136 SO ASTROPHYSICAL JOURNAL LA English DT Article DE DUST, EXTINCTION; ISM, ABUNDANCES; ISM, INDIVIDUAL (GL 2136); ISM, MOLECULES ID TAURUS DARK CLOUDS; INFRARED-SPECTROSCOPY; ABSORPTION FEATURES; SOLID METHANOL; SPECTRA; DUST; CO; CHEMISTRY AB We present ground-based spectra in the 10 and 20 mum atmospheric windows of the deeply embedded protostar GL 2136. These reveal narrow absorption features at 9.7 and 8.9 mum, which we ascribe to the CO-stretch and CH3 rock (respectively) of solid methanol in grain mantles. The peak position of the 9.7 mum band implies that methanol is an important ice mantle component (i.e., CH3OH/H2O > 0.5). However, the CH3OH/H2O abundance ratio derived from the observed column densities is only 0.1. This discrepancy suggests that the solid methanol and water ice are located in independent grain components. These independent components may reflect chemical differentiation during grain mantle formation and/or partial outgassing close to the protostar. C1 LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,EXPTL ASTROPHYS LAB,LIVERMORE,CA 94550. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. UNIV LONDON UNIV COLL,DEPT PHYS & ASTRON,LONDON WC1E 6BT,ENGLAND. RI Barlow, Michael/A-5638-2009 OI Barlow, Michael/0000-0002-3875-1171 NR 24 TC 80 Z9 80 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1992 VL 399 IS 1 BP L79 EP L82 DI 10.1086/186611 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV048 UT WOS:A1992JV04800021 ER PT J AU WAINSCOAT, RJ COHEN, M VOLK, K WALKER, HJ SCHWARTZ, DE AF WAINSCOAT, RJ COHEN, M VOLK, K WALKER, HJ SCHWARTZ, DE TI A MODEL OF THE 8-25 MICRON POINT-SOURCE INFRARED SKY SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE GALAXY, STRUCTURE; INFRARED, GENERAL ID GALACTIC THICK DISK; PHOTOMETRIC SPACE DENSITIES; ON SPIRAL GALAXIES; LOW-RESOLUTION SPECTRA; BASLE HALO PROGRAM; LOW-MASS STARS; T-TAURI STARS; ASYMPTOTIC GIANT BRANCH; DEEP IRAS SURVEY; SURFACE PHOTOMETRY AB We present a detailed model for the infrared point source sky that comprises geometrically and physically realistic representations of the Galactic disk, bulge, stellar halo, spiral arms (including the "local arm"), molecular ring, and the extragalactic sky. We represent each of the distinct Galactic components by up to 87 types of Galactic source, each fully characterized by scale heights, space densities, and absolute magnitudes at BVJHK, 12, and 25 mum. Our model has been guided by a parallel Monte Carlo simulation of the Galaxy at 12 mum. The content of our Galactic source table constitutes an excellent match to the 12 mum luminosity function in the simulation, as well as to the luminosity functions at V and K. We are able to produce differential and cumulative infrared source counts for any bandpass lying fully within the IRAS Low-Resolution Spectrometer's range (7.7-22.7 mum) as well as for the IRAS 12 and 25 mum bands. These source counts match the IRAS observations extremely well. The model can be used to predict the character of the point source sky expected for observations from future infrared space experiments (e.g., ISO, SIRTF, LDR, 2MASS). C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. JAMIESON SCI & ENGN INC,BERKELEY,CA. UNIV CALIF BERKELEY,RADIO ASTRON LAB,BERKELEY,CA 94720. NR 135 TC 357 Z9 358 U1 1 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 1992 VL 83 IS 1 BP 111 EP 146 DI 10.1086/191733 PG 36 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JU071 UT WOS:A1992JU07100005 ER PT J AU SINGH, HB SALAS, L VIEZEE, W SITTON, B FEREK, R AF SINGH, HB SALAS, L VIEZEE, W SITTON, B FEREK, R TI MEASUREMENT OF VOLATILE ORGANIC-CHEMICALS AT SELECTED SITES IN CALIFORNIA SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE URBAN AIR POLLUTION; VOLATILE ORGANIC CHEMICALS; TOXIC CHEMICALS; HALOCARBONS; BENZENE ID AMBIENT AIR; EMISSIONS; ATMOSPHERE; RELEASE; AVERAGE AB Urban air concentrations of 24 selected volatile organic chemicals that may be potentially hazardous to human health and environment were measured during field experiments conducted at two California locations, at Houston, TX, and at Denver, CO. Chemicals measured included chlorofluorocarbons, halomethanes, haloethanes, halopropanes, chloroethylenes and aromatic hydrocarbons. With emphasis on California sites, data from these studies are anlaysed and interpreted with respect to variabilities in ambient air concentrations, diurnal changes, relation to prevailing meteorology, sources and trends. Except in a few instances, mean concentrations are typically between 0 and 5 ppb. Significant variabilities in atmospheric concentrations associated with intense sources and adverse meteorological conditions are shown to exist. In addition to short-term variability, there is evidence of systematic diurnal and seasonal trends. In some instances it is possible to detect declining trends (e.g. ethylene dibromide and chloroethylenes) resulting from the effectiveness of control strategies. C1 SRI INT,MENLO PK,CA 94025. SYNERNET CORP,MOFFETT FIELD,CA 94035. UNIV WASHINGTON,SEATTLE,WA 98195. RP SINGH, HB (reprint author), NASA,AMES RES CTR,MOFFETT FIELD,CA 94035, USA. NR 26 TC 51 Z9 51 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1992 VL 26 IS 16 BP 2929 EP 2946 DI 10.1016/0960-1686(92)90285-S PG 18 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA JY218 UT WOS:A1992JY21800008 ER PT J AU SNETSINGER, KG PUESCHEL, RF FERRY, GV VERMA, S AF SNETSINGER, KG PUESCHEL, RF FERRY, GV VERMA, S TI DIMINISHED EFFECTS OF EL-CHICHON ON STRATOSPHERIC AEROSOLS, EARLY 1984 TO LATE 1986 SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE AEROSOLS; VOLCANO; STRATOSPHERE AB Stratospheric aerosol collections by wire impactors, taken mainly over the western United States from early 1984 to late 1986, show the diminishing effects of El Chichon's 1982 eruption, and provide a set of data for judging subsequent volcanic effects (e.g. Pinatubo). Decrease in sulfate burden during the study time is due to preferential gravitational settling-out of large (>0.5 mum diameter) sulfate aerosol droplets. As a result of settling from higher levels, lower altitude (12.2-15.2 km) air early in 1984 tends to contain more sulfate than higher level (19.8-21.3 km) air. As of late 1986, however, high- and low-altitude sulfate contents have decreased and are similar, suggesting large-particle settling has been completed. The later sulfate collections also have size distributions that in shape resemble unimodal background spectra, whereas earlier ones are bimodal. Average sulfate load for all altitudes decreases during the period of study from 0.4 to 0.08 mug m-3. The latter value is somewhat higher than a volcanically unenriched pre-El Chichon level (0.05 mug m-3) suggesting that even as of 1987, stratospheric background had not been obtained. C1 TMA NORCAL INC,RICHMOND,CA 94804. RP SNETSINGER, KG (reprint author), NASA,AMES RES CTR,MOFFETT FIELD,CA 94035, USA. NR 8 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1992 VL 26 IS 16 BP 2947 EP 2951 DI 10.1016/0960-1686(92)90286-T PG 5 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA JY218 UT WOS:A1992JY21800009 ER PT J AU KUMAR, KV CALKINS, DS WALIGORA, JM GILBERT, JH POWELL, MR AF KUMAR, KV CALKINS, DS WALIGORA, JM GILBERT, JH POWELL, MR TI TIME TO DETECTION OF CIRCULATING MICROBUBBLES AS A RISK FACTOR FOR SYMPTOMS OF ALTITUDE DECOMPRESSION-SICKNESS SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID BUBBLES AB This study investigated the association between time at onset of circulating microbubbles (CMB) and symptoms of altitude decompression sickness (DCS), using Cox proportional hazard regression models. The study population consisted of 125 individuals who participated in direct ascent, simulated extravehicular activities profiles. Using individual CMB status as a time-dependent variable, we found that the hazard for symptoms increased significantly (at the end of 180 min at altitude) in the presence of CMB (Hazard Ratio = 29.59; 95% confidence interval [95% CI] = 7.66-114.27), compared to no CMB. Further examination was conducted on the subgroup of individuals who developed microbubbles during the test (n = 49), by using Cox regression. Individuals with late onset of CMB (>60 min at altitude) showed a significantly reduced risk of symptoms (hazard ratio = 0.92; 95% CI = 0.89-0.95), compared to those with early onset (less-than-or-equal-to 60 min), while controlling for other risk factors. We conclude that time to detection of circulating microbubbles is an independent determinant of symptoms of DCS. C1 NASA,LYNDON B JOHNSON SPACE CTR,SPACE BIOMED RES INST,HOUSTON,TX 77058. RP KUMAR, KV (reprint author), KRUG LIFE SCI,1290 HERCULES DR,SUITE 120,HOUSTON,TX 77058, USA. NR 18 TC 20 Z9 20 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD NOV PY 1992 VL 63 IS 11 BP 961 EP 964 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA JV794 UT WOS:A1992JV79400003 PM 1445159 ER PT J AU KOHL, RL AF KOHL, RL TI BETA-ENDORPHIN AND ARGININE VASOPRESSIN FOLLOWING STRESSFUL SENSORY STIMULI IN MAN SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID MOTION SICKNESS; SUSCEPTIBILITY; CHEMOTHERAPY; SECRETION; RELEASE; REFLEX; EMESIS AB This experimentation partially defines, for the first time, the response of beta-endorphin (ENDO) in man during tests designed to elicit nausea and motion sickness. These responses are similar to those associated with arginine vasopressin (AVP) and adrenocorticotropin (ACTH) to the extent that all hormones rise in response to motion sickness (p < 0.003). Repeated exposure diminished motion-induced release of ENDO (p < 0.005) and AVP (p < 0.004) despite a three-fold increase in resistance to motion stimuli. Higher post-stress levels of AVP (p < 0.04) and ACTH (p < 0.02) were correlated with greater resistance to motion sickness. These data support the hypothesis that release of AVP is a significant link between stressful motion and motion-induced nausea and other autonomic system changes. Further, resistant individuals apparently can tolerate higher peripheral levels of AVP before nausea results. Peripheral release of ENDO and ACTH may follow release of AVP; however, given the extensive and complex functional interactions that exist between AVP and the opiate systems, it is not yet possible to define a clear role for ENDO in the etiology of motion sickness. C1 NASA,LYNDON B JOHNSON SPACE CTR,SPACE BIOMED RES INST,HOUSTON,TX 77058. UNIV TEXAS,MED BRANCH,DEPT PHARMACOL & TOXICOL,GALVESTON,TX 77550. NR 25 TC 20 Z9 24 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD NOV PY 1992 VL 63 IS 11 BP 986 EP 993 PG 8 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA JV794 UT WOS:A1992JV79400008 PM 1332670 ER PT J AU CONVERTINO, VA DOERR, DF GUELL, A MARINI, JF AF CONVERTINO, VA DOERR, DF GUELL, A MARINI, JF TI EFFECTS OF ACUTE EXERCISE ON ATTENUATED VAGAL BAROREFLEX FUNCTION DURING BED REST SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID BARORECEPTOR-CARDIAC REFLEX; ORTHOSTATIC HYPOTENSION; RESPONSES; PRESSURE; HUMANS; NOREPINEPHRINE; STIMULATION; VOLUME; DOGS AB We measured carotid baroreceptor-cardiac reflex responses in six healthy men, 24 h before and 24 h after a bout of leg exercise during 6-degrees head-down bed rest to determine if depressed vagal baroreflex function associated with exposure to microgravity environments could be reversed by a single exposure to acute intense exercise. Baroreflex responses were measured before bed rest and on day 7 of bed rest. An exercise bout consisting of dynamic and isometric actions of the quadriceps at graded speeds and resistances was performed on day 8 of bed rest and measurements of baroreflex response were repeated 24 h later. Vagally-mediated cardiac responses were provoked with ramped neck pressure-suction sequences comprising pressure elevations to +40 mm Hg, followed by serial, R-wave triggered 15 mm Hg reductions, to -65 mm Hg. Baroreceptor stimulus-cardiac response relationships were derived by plotting each R-R interval as a function of systolic pressure less the neck chamber pressure applied during the interval. Compared with pre-bed rest baseline measurements, 7 d of bed rest decreased the gain (maximum slope) of the baroreflex stimulus-response relationship by 16.8 +/- 3.4% (p < 0.05). On day 9 of bed rest, 24 h after exercise, the maximum slope of the baroreflex stimulus-response relationship was increased (p < 0.05) by 10.7 +/- 3.7% above pre-bed rest levels and 34.3 +/- 7.9% above bed rest day 7. Our data verify that vagally-mediated baroreflex function is depressed by exposure to simulated microgravity and demonstrate that this effect can be acutely reversed by exposure to a single bout of intense exercise. C1 INST MED & PHYSIOL SPATIALES,F-31052 TOULOUSE,FRANCE. RP CONVERTINO, VA (reprint author), NASA,BIOMED OPERAT & RES OFF,MAIL CODE MD-P,KENNEDY SPACE CTR,FL 32899, USA. NR 27 TC 14 Z9 14 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD NOV PY 1992 VL 63 IS 11 BP 999 EP 1003 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA JV794 UT WOS:A1992JV79400010 PM 1445165 ER PT J AU BLACKWELL, AL AF BLACKWELL, AL TI DIFFERENTIAL SOLUTION SO BIOSCIENCE LA English DT Letter RP BLACKWELL, AL (reprint author), NASA,AMES RES CTR,DIV SPACE PROJECTS,SYST DEV BRANCH,MOFFETT FIELD,CA 94035, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST BIOLOGICAL SCI PI WASHINGTON PA 1444 EYE ST, NW, STE 200, WASHINGTON, DC 20005 SN 0006-3568 J9 BIOSCIENCE JI Bioscience PD NOV PY 1992 VL 42 IS 10 BP 743 EP 743 DI 10.2307/1311990 PG 1 WC Biology SC Life Sciences & Biomedicine - Other Topics GA JU829 UT WOS:A1992JU82900011 ER PT J AU WELCH, RB COHEN, MM DEROSHIA, CW AF WELCH, RB COHEN, MM DEROSHIA, CW TI VISUAL-MOTOR EFFECTS OF PROLONGED EXPOSURE TO 2-G IN THE HUMAN CENTRIFUGE SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 442 EP 442 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700039 ER PT J AU ELLIS, SR BUCHER, UJ AF ELLIS, SR BUCHER, UJ TI DEPTH-PERCEPTION OF STEREOSCOPICALLY PRESENTED VIRTUAL OBJECTS INTERACTING WITH REAL BACKGROUND PATTERNS SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. UNIV CALIF BERKELEY,BERKELEY,CA 94720. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 443 EP 443 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700050 ER PT J AU BRIDGEMAN, B ANAND, S BROWMAN, KE WELCH, RB AF BRIDGEMAN, B ANAND, S BROWMAN, KE WELCH, RB TI NECESSARY CONDITIONS FOR SPEEDED VISUOMOTOR ADAPTATION SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 UNIV CALIF SANTA CRUZ,SANTA CRUZ,CA 95064. UNIV MICHIGAN,ANN ARBOR,MI 48109. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 453 EP 453 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700160 ER PT J AU MCBEATH, MK AF MCBEATH, MK TI THE BASKETBALL HOOP ILLUSION SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 453 EP 453 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700164 ER PT J AU KAISER, MK KELLMAN, PJ BANKS, MS AIKEN, WH AF KAISER, MK KELLMAN, PJ BANKS, MS AIKEN, WH TI PERCEPTION OF TARGET MOTION BY PASSIVELY MOVING OBSERVERS SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. SWARTHMORE COLL,SWARTHMORE,PA 19081. UNIV CALIF BERKELEY,BERKELEY,CA 94720. UNIV CALIF SANTA CRUZ,SANTA CRUZ,CA 95064. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 470 EP 470 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700355 ER PT J AU HORLITZ, KL JOHNSTON, JC REMINGTON, RW AF HORLITZ, KL JOHNSTON, JC REMINGTON, RW TI WHAT MAKES IT DIFFICULT TO PROCESS MULTIPLE TARGETS IN RAPID SERIAL VISUAL PRESENTATION SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 474 EP 474 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700401 ER PT J AU MCCANN, RS JOHNSTON, JC REMINGTON, RW AF MCCANN, RS JOHNSTON, JC REMINGTON, RW TI DISSOCIATIVE EFFECTS OF 2 DIFFERENT ATTENTIONAL MANIPULATIONS - EVIDENCE FOR 2 ATTENTIONAL BOTTLENECKS SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 STERLING SOFTWARE,PALO ALTO,CA. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 475 EP 475 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700402 ER PT J AU MCBEATH, MK SCHIANO, DJ AF MCBEATH, MK SCHIANO, DJ TI DEGREE OF FIGURAL SYMMETRY SPECIFIES ORIENTATION OF INTERPRETED OBJECTS SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. STANFORD UNIV,STANFORD,CA 94305. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 476 EP 476 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700408 ER PT J AU HANNA, A LOFTUS, G AF HANNA, A LOFTUS, G TI A MODEL FOR CONCEPTUAL PROCESSING OF NATURALISTIC SCENES SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. UNIV WASHINGTON,SEATTLE,WA 98195. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 478 EP 478 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700435 ER PT J AU FOLK, CL REMINGTON, RW AF FOLK, CL REMINGTON, RW TI APPARENT MOTION, ATTENTIONAL CAPTURE, AND INHIBITORY ATTENTIONAL CONTROL SETTINGS SO BULLETIN OF THE PSYCHONOMIC SOCIETY LA English DT Meeting Abstract C1 VILLANOVA UNIV,VILLANOVA,PA 19085. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RI Martin Arevalo, Elisa/L-4472-2014 OI Martin Arevalo, Elisa/0000-0002-4546-6440 NR 0 TC 0 Z9 0 U1 0 U2 2 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 SN 0090-5054 J9 B PSYCHONOMIC SOC PD NOV PY 1992 VL 30 IS 6 BP 481 EP 481 PG 1 WC Psychology, Mathematical SC Psychology GA JV167 UT WOS:A1992JV16700474 ER PT J AU MARTIN, AP HUMPHREYS, R PALUMBI, SR AF MARTIN, AP HUMPHREYS, R PALUMBI, SR TI POPULATION GENETIC-STRUCTURE OF THE ARMORHEAD, PSEUDOPENTACEROS-WHEELERI, IN THE NORTH PACIFIC-OCEAN - APPLICATION OF THE POLYMERASE CHAIN-REACTION TO FISHERIES PROBLEMS SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID MITOCHONDRIAL-DNA; PENTACEROTIDAE; EVOLUTION; SEQUENCES; FLOW AB Armorhead (Pseudopentaceros wheeleri) occur in the subarctic, epipelagic habitats of the northern Pacific Ocean and are known to reproduce on seamounts in the central Pacific. Over the last few decades, overexploitation of seamount populations led to dramatic declines in abundances of reproductive populations. We undertook a study of the population genetics of armorhead to test whether distinct stocks exist in association with specific seamounts. We used the polymerase chain reaction (PCR) and a combination of DNA sequencing and restriction fragment length polymorphism (RFLP) analysis to analyze mtDNA variants for individuals collected from three localities: two seamounts and from the open ocean. We discovered that mtDNA haplotypes are not partitioned geographically, refuting the hypothesis that different seamounts harbor genetically distinct populations. Furthermore, genetic similarity of seamount and open-ocean fish supports the hypothesis that armorhead migrate between the central and northern Pacific Ocean for reproduction and feeding, respectively. C1 UNIV HAWAII,KEWALO MARINE LAB,HONOLULU,HI 96822. SMITHSONIAN TROP RES INST,NAOS MARINE LAB,MIAMI,FL 34002. NATL MARINE FISHERIES SERV,SW FISHERIES CTR,HONOLULU LAB,HONOLULU,HI 96822. RP MARTIN, AP (reprint author), UNIV HAWAII,DEPT ZOOL,HONOLULU,HI 96822, USA. NR 21 TC 42 Z9 45 U1 2 U2 6 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD NOV PY 1992 VL 49 IS 11 BP 2386 EP 2391 PG 6 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA KF388 UT WOS:A1992KF38800021 ER PT J AU STEINBERG, TA WILSON, DB BENZ, F AF STEINBERG, TA WILSON, DB BENZ, F TI THE COMBUSTION PHASE OF BURNING METALS SO COMBUSTION AND FLAME LA English DT Article AB Glassman's hypothesis and bum ratio are examined for their suitability for predicting the phase of combustion of metals. Neither criterion is validated based on either published property values or experimental evidence. Inconsistencies in published property values and definitions are noted. Computer calculations provide a more appropriate description of the composition of the combustion products and the adiabatic flame temperature of a burning metal at equilibrium. Dissociation temperatures (and product compositions) for 11 metals are computed using a specified quantity of thermal energy and compared with adiabatic flame temperatures. C1 NASA,WHITE SANDS TEST FACIL,LAS CRUCES,NM. RP STEINBERG, TA (reprint author), LOCKHEED ENGN & SCI CO,WHITE SANDS TEST FACIL,LAS CRUCES,NM 88004, USA. OI Steinberg, Theodore/0000-0002-9270-4130 NR 28 TC 19 Z9 23 U1 2 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD NOV PY 1992 VL 91 IS 2 BP 200 EP 208 DI 10.1016/0010-2180(92)90100-4 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA JR772 UT WOS:A1992JR77200007 ER PT J AU THOMAS, RE RICE, SD AF THOMAS, RE RICE, SD TI SALINITY TOLERANCE OF ADULT AND JUVENILE RED KING CRABS PARALITHODES-CAMTSCHATICA SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-PHYSIOLOGY LA English DT Article ID TEMPERATURE AB 1. Juvenile king crabs were more tolerant of reduced salinities than adult crab; juvenile crab were better volume regulators at reduced salinities than adult crab. 2. Adult female king crab hemolymph was hyperosmotic to full seawater (30 ppt) and isosmotic to dilute seawater. Juvenile king crab (2 years old) were hypoosmotic at the same concentrations. 3. Lower osmotic concentration of juvenile hemolymph is at least partially due to lower sodium concentration. 4. Juvenile king crab can tolerate some dilution and survive for short periods in the reduced salinity of the lower intertidal zone. C1 NATL MARINE FISHERIES SERV,AUKE BAY LAB,JUNEAU,AK 99801. RP THOMAS, RE (reprint author), CALIF STATE UNIV CHICO,DEPT BIOL SCI,CHICO,CA 95929, USA. NR 10 TC 6 Z9 6 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0300-9629 J9 COMP BIOCHEM PHYS A JI Comp. Biochem. Physiol. A-Physiol. PD NOV PY 1992 VL 103 IS 3 BP 433 EP 437 DI 10.1016/0300-9629(92)90268-U PG 5 WC Biochemistry & Molecular Biology; Physiology; Zoology SC Biochemistry & Molecular Biology; Physiology; Zoology GA JW966 UT WOS:A1992JW96600002 ER PT J AU THY, P LOFGREN, GE AF THY, P LOFGREN, GE TI EXPERIMENTAL CONSTRAINTS ON THE LOW-PRESSURE EVOLUTION OF TRANSITIONAL AND MILDLY ALKALIC BASALTS - MULTISATURATED LIQUIDS AND COEXISTING AUGITES SO CONTRIBUTIONS TO MINERALOGY AND PETROLOGY LA English DT Article ID EXPERIMENTAL PETROLOGY; PHASE-EQUILIBRIA; SOLID-SOLUTIONS; FRACTURE-ZONE; PLAGIOCLASE; THOLEIITES; FORSTERITE; GENERATION; DIOPSIDE; CRYSTALLIZATION AB Basaltic liquids, saturated at one-atmosphere in augite, olivine, and plagioclase, show a strong linear trend in pseudo-quaternary projections from nepheline to slightly quartz normative compositions. Coexisting augites show a corresponding variation from slightly nepheline to hypersthene normative compositions. Consequently, alkalic and mildly alkalic liquids coexist with nepheline normative augites; tholeiitic liquids coexist with hypersthene normative augites; and transitional liquids coexist with augites compositionally intermediate between those crystallizing in alkalic and tholeiitic melts. The variation in augite composition is due to a decrease in wollastonite and non-quadrilateral components, going from mildly alkalic, to transitional, and tholeiitic augites. The observed liquid and augite trends lack correlations between normative composition and crystallization temperature. This is an artifact of plotting unrelated liquid lines of descent. Individual liquid lines of descent, in contrast, display good correlation between normative composition and crystallization temperature, which, for both liquids and coexisting augites, are highly oblique to nearly perpendicular to the general trend. Because the composition of the first augite to appear on the liquidus varies as a function of the bulk system, the location of the thermal divide shows corresponding variations. As a consequence, unifying cotectics and pseudo-quaternary normative projections should not, without specific experimental knowledge, be used to address' liquid lines of descent and common magmatic parentages. C1 NASA,LYNDON B JOHNSON SPACE CTR,SN2,HOUSTON,TX 77058. NR 30 TC 13 Z9 13 U1 0 U2 4 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0010-7999 J9 CONTRIB MINERAL PETR JI Contrib. Mineral. Petrol. PD NOV PY 1992 VL 112 IS 2-3 BP 196 EP 202 DI 10.1007/BF00310454 PG 7 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA JW672 UT WOS:A1992JW67200004 ER PT J AU TREIMAN, AH SUTTON, SR AF TREIMAN, AH SUTTON, SR TI PETROGENESIS OF THE ZAGAMI METEORITE - INFERENCES FROM SYNCHROTRON X-RAY (SXRF) MICROPROBE AND ELECTRON-MICROPROBE ANALYSES OF PYROXENES SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID DIFFUSION EXPERIMENTS; OLIVINE-MELT; CRYSTALLIZATION; COEFFICIENTS; PHENOCRYSTS; SHERGOTTY; DIFFERENTIATION; CLINOPYROXENES; FLUORESCENCE; ACHONDRITES AB The Zagami meteorite is a shergottite, a basalt rich in pigeonite, augite, and maskelynite glass (shocked plagioclase). It is one of the SNC meteorites, which are inferred to have formed on Mars. Major and minor element abundances in pyroxene, principally pigeonite, from newly available (UNM) samples were determined by electron microprobe; abundances of trace elements Ni, Cu, Zn, and Ga were obtained by synchrotron X-ray (SXRF) microprobe. Many pigeonite grains have normally zoned rims and reversely zoned cores, so that the most magnesian pigeonite forms rings or annuli in thin section view; in three dimensions, the most magnesian pigeonite may form tubes or hourglass shapes. The cores commonly contain magmatic inclusions. Other pigeonites have irregular or multiple magnesian regions, with magmatic inclusions among and between them. Abundances of Ni and Cr in the magnesian zones and cores are partially decoupled from abundances of other compatible (Mg) and incompatible (Fe, Ti) elements. The textures, chemical zoning, and element decouplings in the pigeonites are consistent with igneous crystal growth at moderate cooling rates, not isothermally or near equilibrium. From element partitioning and mass balance, the UNM Zagami is estimated to contain 20 +/- 5% or less cumulus pyroxene (half augite and half pigeonite), half the proportion suggested by equilibrium distribution of Fe/Mg between pigeonite and melt. This inconsistency may be resolved if all pigeonite/melt element partitioning was affected by the rapid growth of the pigeonites. The composition of the parental magma for the UNM Zagami, calculated by mass balance on bulk and pyroxene compositions, is similar to the 1170-degrees-C melt of the BMNH Zagami, not the 1140-degrees-C melt inferred as parental by other workers. The inference that the pyroxene zoning patterns reflect only magmatic events is consistent with an igneous age of 180 m.y. for Zagami. C1 UNIV CHICAGO,DEPT GEOPHYS SCI,CHICAGO,IL 60637. UNIV CHICAGO,CONSORTIUM ADV RADIAT SOURCES,CHICAGO,IL 60637. BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973. RP TREIMAN, AH (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,SN21,HOUSTON,TX 77058, USA. NR 67 TC 39 Z9 39 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD NOV PY 1992 VL 56 IS 11 BP 4059 EP 4074 DI 10.1016/0016-7037(92)90016-C PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JW846 UT WOS:A1992JW84600015 ER PT J AU MERRITTS, DJ CHADWICK, OA HENDRICKS, DM BRIMHALL, GH LEWIS, CJ AF MERRITTS, DJ CHADWICK, OA HENDRICKS, DM BRIMHALL, GH LEWIS, CJ TI THE MASS BALANCE OF SOIL EVOLUTION ON LATE QUATERNARY MARINE TERRACES, NORTHERN CALIFORNIA SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID SEA-LEVEL; CHRONOSEQUENCE; RATES; PEDOGENESIS; CALIBRATION AB Mass-balance interpretation of a soil chronosequence provides a means of quantifying elemental addition, removal, and transformation that occur in soils from a flight of marine terraces in northern California. Six soil profiles that range in age from several to 240,000 yr are developed in unconsolidated, sandy-marine, and eolian parent material deposited on bedrock marine platforms. Soil evolution is dominated by (1) open-system depletion of Si, Ca, Mg, K, and Na; (2) open-system enrichment of P in surface soil horizons; (3) relative immobility of Fe and Al; and (4) transformation of Fe, Si, and Al in the parent material to secondary clay minerals and sesquioxides. Net mass losses of bases and Si are generally uniform with depth and substantial-in some cases approaching 100%; however, the rate of loss of each element differs markedly, causing the ranking of each by relative abundance to shift with time. Loss of Si from the sand fraction by dissolution and particle-size diminution, from approximately 100% to <35% over 240 ky, mirrors a similar gain in the silt (from approximately 2% to 30%-50%) and clay (from approximately 0% to approximately 20%) size fractions. The Fe originally present in the sand fraction decreases from >80% to <10%, whereas the amount of Fe present in the clay and crystalline oxyhydroxide fractions increases to 25% and 70%, respectively. Aluminum originally present in the sand fraction decreases from >90% to <10% concurrently with an increase of Al in the organic sesquioxide and clay phases, to 10% and 50%, respectively, while only minor increases occur in the nonorganic sesquioxide phases. C1 UNIV CALIF BERKELEY,DEPT GEOL & GEOPHYS,BERKELEY,CA 94720. JET PROP LAB,PASADENA,CA 91109. UNIV ARIZONA,DEPT SOIL & WATER SCI,TUCSON,AZ 85721. RP MERRITTS, DJ (reprint author), FRANKLIN & MARSHALL COLL,DEPT GEOSCI,LANCASTER,PA 17604, USA. NR 38 TC 52 Z9 54 U1 1 U2 16 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD NOV PY 1992 VL 104 IS 11 BP 1456 EP 1470 DI 10.1130/0016-7606(1992)104<1456:TMBOSE>2.3.CO;2 PG 15 WC Geosciences, Multidisciplinary SC Geology GA JW832 UT WOS:A1992JW83200005 ER PT J AU ASRAR, G TILFORD, SG BUTLER, DM AF ASRAR, G TILFORD, SG BUTLER, DM TI MISSION TO PLANET EARTH - EARTH OBSERVING SYSTEM SO GLOBAL AND PLANETARY CHANGE LA English DT Article AB Earth Observing System (EOS) is one of the components of the Mission to Planet Earth (MTPE) concept for an international Earth science program to provide the observations, understanding and modeling capabilities needed to assess the impact of natural events and human induced activities on the Earth's environment. MTPE is envisioned to have both the space-based and ground-based observational capabilities, along with the necessary data and information system(s) to accommodate the acquisition, archive and distribution of the data and information acquired about the Earth system. The knowledge gained through this multidisciplinary and international scientific partnership will help increase our understanding of the functioning of the Earth as a coupled system, a prerequisite to informed management of the planet's resources and to the preservation of the global environment. RP ASRAR, G (reprint author), NASA,OFF SPACE SCI & APPLICAT,DIV EARTH SCI & APPLICAT,WASHINGTON,DC 20546, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD NOV PY 1992 VL 98 IS 1 BP 3 EP 8 PG 6 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA KB342 UT WOS:A1992KB34200002 ER PT J AU SCHOEBERL, M PFAENDTNER, J ROOD, R THOMPSON, A WIELICKI, B AF SCHOEBERL, M PFAENDTNER, J ROOD, R THOMPSON, A WIELICKI, B TI ATMOSPHERES PANEL REPORT TO THE PAYLOAD PANEL SO GLOBAL AND PLANETARY CHANGE LA English DT Article C1 NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP SCHOEBERL, M (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD NOV PY 1992 VL 98 IS 1 BP 9 EP 21 PG 13 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA KB342 UT WOS:A1992KB34200003 ER PT J AU BROWN, CS COX, WM DRESCHEL, TW CHETIRKIN, PV AF BROWN, CS COX, WM DRESCHEL, TW CHETIRKIN, PV TI THE VACUUM-OPERATED NUTRIENT DELIVERY SYSTEM - HYDROPONICS FOR MICROGRAVITY SO HORTSCIENCE LA English DT Article DE PHASEOLUS-VULGARIS; REDUCED PRESSURE AB A nutrient delivery system that may have applicability for growing plants in microgravity is described. The Vacuum-Operated Nutrient Delivery System (VONDS) draws nutrient solution across roots that are under a partial vacuum at almost-equal-to 91 kPa. Bean (Phaseolus vulgaris L. cv. Blue Lake 274) plants grown on the VONDS had consistently greater leaf area and higher root, stem, leaf, and pod dry weights than plants grown under nonvacuum control conditions. This study demonstrates the potential applicability of the VONDS for growing plants in microgravity for space biology experimentation and/or crop production. C1 NASA,BIOMED ENGN OFF,KENNEDY SPACE CTR,FL 32899. RP BROWN, CS (reprint author), BIONET CORP,MAIL CODE BIO-3,KENNEDY SPACE CTR,FL 32899, USA. OI Dreschel, Thomas/0000-0003-2211-5733 NR 5 TC 6 Z9 6 U1 0 U2 3 PU AMER SOC HORTICULTURAL SCIENCE PI ALEXANDRIA PA 701 NORTH SAINT ASAPH STREET, ALEXANDRIA, VA 22314-1998 SN 0018-5345 J9 HORTSCIENCE JI Hortscience PD NOV PY 1992 VL 27 IS 11 BP 1183 EP 1185 PG 3 WC Horticulture SC Agriculture GA KE220 UT WOS:A1992KE22000004 PM 11537607 ER PT J AU SCHAEFER, BE BULDER, HJJ BOURGEOIS, J AF SCHAEFER, BE BULDER, HJJ BOURGEOIS, J TI LUNAR OCCULTATION VISIBILITY SO ICARUS LA English DT Article ID SKY BRIGHTNESS C1 REUX ASTRON STN,B-5590 CINEY,BELGIUM. RP SCHAEFER, BE (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 661,GREENBELT,MD 20771, USA. NR 23 TC 3 Z9 3 U1 1 U2 2 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD NOV PY 1992 VL 100 IS 1 BP 60 EP 72 DI 10.1016/0019-1035(92)90018-3 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB092 UT WOS:A1992KB09200005 ER PT J AU SPRAGUE, AL WITTEBORN, FC KOZLOWSKI, RW CRUIKSHANK, DP BARTHOLOMEW, MJ GRAPS, AL AF SPRAGUE, AL WITTEBORN, FC KOZLOWSKI, RW CRUIKSHANK, DP BARTHOLOMEW, MJ GRAPS, AL TI THE MOON - MIDINFRARED (7.5-MU-M TO 11.4-MU-M) SPECTROSCOPY OF SELECTED REGIONS SO ICARUS LA English DT Article ID PARTICULATE PLANETARY SURFACES; THERMAL EMISSION; REFLECTANCE SPECTRA; FEATURES C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. SUSQUEHANNA UNIV,SELINSGROVE,PA 17870. STERLING SOFTWARE INC,PALO ALTO,CA 94035. RP SPRAGUE, AL (reprint author), UNIV ARIZONA,LUNAR & PLANETARY LAB,TUCSON,AZ 85721, USA. NR 63 TC 19 Z9 19 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD NOV PY 1992 VL 100 IS 1 BP 73 EP 84 DI 10.1016/0019-1035(92)90019-4 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB092 UT WOS:A1992KB09200006 ER PT J AU VILAS, F MCFADDEN, LA AF VILAS, F MCFADDEN, LA TI CCD REFLECTANCE SPECTRA OF SELECTED ASTEROIDS .1. PRESENTATION AND DATA-ANALYSIS CONSIDERATIONS SO ICARUS LA English DT Article ID LOW-ALBEDO ASTEROIDS; COMETARY NUCLEI; BELT C1 UNIV CALIF SAN DIEGO,CALIF SPACE INST 0216,LA JOLLA,CA 92093. UNIV MARYLAND,ASTRON PROGRAM,COLL PK,MD 20742. RP VILAS, F (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058, USA. RI McFadden, Lucy-Ann/I-4902-2013 OI McFadden, Lucy-Ann/0000-0002-0537-9975 NR 42 TC 57 Z9 57 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD NOV PY 1992 VL 100 IS 1 BP 85 EP 94 DI 10.1016/0019-1035(92)90020-8 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB092 UT WOS:A1992KB09200007 ER PT J AU WEST, RA FRIEDSON, AJ APPLEBY, JF AF WEST, RA FRIEDSON, AJ APPLEBY, JF TI JOVIAN LARGE-SCALE STRATOSPHERIC CIRCULATION SO ICARUS LA English DT Article ID METHANE BAND PHOTOMETRY; SOUTH EQUATORIAL BELT; TROPICAL ZONE; JUPITER; SATURN; HAZE; REFLECTIVITY; ATMOSPHERES; ABSORPTION; AEROSOLS RP WEST, RA (reprint author), JET PROP LAB,MS 169-237,PASADENA,CA 91109, USA. NR 36 TC 49 Z9 49 U1 0 U2 2 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD NOV PY 1992 VL 100 IS 1 BP 245 EP 259 DI 10.1016/0019-1035(92)90033-4 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KB092 UT WOS:A1992KB09200020 ER PT J AU THOMAS, M DAGLI, N WALDMAN, J GOSSARD, A YUH, E GWINN, E MULLER, R MAKER, P AF THOMAS, M DAGLI, N WALDMAN, J GOSSARD, A YUH, E GWINN, E MULLER, R MAKER, P TI CURRENT SWITCHING AND MODULATION BASED ON ELECTRON INTERFERENCE IN ELECTRON WAVE-GUIDES - A ZERO GAP ELECTRON WAVE COUPLER SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Meeting Abstract C1 UNIV CALIF SANTA BARBARA,DEPT ELECT & COMP ENGN,SANTA BARBARA,CA 93106. UNIV CALIF SANTA BARBARA,DEPT PHYS,SANTA BARBARA,CA 93106. JET PROP LAB,PASADENA,CA 91109. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD NOV PY 1992 VL 39 IS 11 BP 2643 EP 2644 DI 10.1109/16.163493 PG 2 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA JU737 UT WOS:A1992JU73700046 ER PT J AU FOROUHAR, S LARSSON, A KSENDZOV, A LANG, RJ AF FOROUHAR, S LARSSON, A KSENDZOV, A LANG, RJ TI ROOM-TEMPERATURE OPERATION OF MOCVD-GROWN GAINAS/INP STRAINED-LAYER MULTIQUANTUM-WELL LASERS IN THE 1.8-MU-M RANGE SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Meeting Abstract C1 JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109. RI Larsson, Anders/P-7275-2015 OI Larsson, Anders/0000-0002-0912-7695 NR 3 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD NOV PY 1992 VL 39 IS 11 BP 2662 EP 2662 DI 10.1109/16.163527 PG 1 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA JU737 UT WOS:A1992JU73700080 ER PT J AU KIM, M SOVERO, EA HO, WJ HACKER, JB RUTLEDGE, DB ROSENBERG, JJ SMITH, RP AF KIM, M SOVERO, EA HO, WJ HACKER, JB RUTLEDGE, DB ROSENBERG, JJ SMITH, RP TI A 10-GHZ QUASI-OPTICAL GRID AMPLIFIER USING INTEGRATED HBT DIFFERENTIAL PAIRS SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Meeting Abstract C1 CALTECH,DIV ENGN & APPL SCI,PASADENA,CA 91125. ROCKWELL INT CORP,CTR SCI,THOUSAND OAKS,CA 91358. GERMANIUM POWER DEVICES CORP,ANDOVER,MA 01810. JET PROP LAB,CTR SPACE MICROELECTR TECHNOL,PASADENA,CA 91109. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD NOV PY 1992 VL 39 IS 11 BP 2667 EP 2668 DI 10.1109/16.163537 PG 2 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA JU737 UT WOS:A1992JU73700090 ER PT J AU FREEMAN, A AF FREEMAN, A TI SAR CALIBRATION - AN OVERVIEW SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Review DE SAR; CALIBRATION; IMAGE QUALITY; POLARIMETRY; INTERFEROMETRY ID SYNTHETIC-APERTURE RADAR; PHASE CALIBRATION; CROSS-SECTION; IMAGERY; REFLECTOR; SYSTEMS; TARGET; INTERFEROMETER; SATELLITE; ACCURACY AB Remote sensing with synthetic aperture radars (SAR's) is a field approaching a new phase in its maturity. Over the next decade, several spaceborne SAR systems, including E-ERS-1, J-ERS-1, SIR-C/X-SAR, Radarsat, and the EOS SAR will produce imagery. The streams of data generated by these systems will pose a considerable challenge to the microwave remote sensing community in terms of relating the data to properties of the Earth's surface. There is an urgent need for the data from these sensors to be calibrated, so that the relationships between radar backscatter and geophysical parameters can be properly established. In this paper, recent progress in SAR calibration is reviewed. The difficulties of calibrating both airborne and spaceborne SAR image data are addressed. The quantities measured by a SAR, i.e., radar backscatter, are defined and mathematical formulations for the three basic types of SAR image developed. The difficulties in establishing science requirements for calibration are discussed. The measurement of SAR image quality is briefly addressed. The problem of radiometric calibration is introduced via the SAR form of the radar equation, with both internal and external calibration approaches considered. The development of algorithms for polarimetric radar calibration is reviewed and the problems involved in phase calibration of interferometric SAR are discussed. Future challenges in the field of SAR calibration are considered. RP FREEMAN, A (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. NR 128 TC 135 Z9 166 U1 6 U2 29 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD NOV PY 1992 VL 30 IS 6 BP 1107 EP 1121 DI 10.1109/36.193786 PG 15 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA KG453 UT WOS:A1992KG45300001 ER PT J AU DUBOIS, PC EVANS, D VANZYL, J AF DUBOIS, PC EVANS, D VANZYL, J TI APPROACH TO DERIVATION OF SIR-C SCIENCE REQUIREMENTS FOR CALIBRATION SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Note DE CALIBRATION REQUIREMENTS; SIR-C; POLARIMETRY ID RADAR AB Many of the experiments proposed for the forthcoming SIR-C mission require calibrated data, for example those which emphasize 1) deriving quantitative geophysical information (e.g., surface roughness and dielectric constant), 2) monitoring daily and seasonal changes in the Earth's surface (e.g., soil moisture), 3) extending local case studies to regional and worldwide scales, and 4) using SIR-C data with other spaceborne sensors (e.g., ERS-1, JERS-1, and Radarsat). There are three different aspects to the SIR-C calibration problem: radiometric and geometric calibration, which have been previously reported, and polarimetric calibration. The study described in this paper is an attempt at determining the science requirements for polarimetric calibration for SIR-C. A model describing the effect of miscalibration is presented first, followed by an example describing how to assess the calibration requirements specific to an experiment. The effects of miscalibration on some commonly used polarimetric parameters are also discussed. It is shown that polarimetric calibration requirements are strongly application dependent. In consequence, the SIR-C investigators are advised to assess the calibration requirements of their own experiment. A set of numbers summarizing SIR-C polarimetric calibration goals concludes this paper. RP DUBOIS, PC (reprint author), JET PROP LAB,PASADENA,CA 91109, USA. RI Dubois-Fernandez, Pascale/A-6743-2012 NR 13 TC 18 Z9 22 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD NOV PY 1992 VL 30 IS 6 BP 1145 EP 1149 DI 10.1109/36.193790 PG 5 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA KG453 UT WOS:A1992KG45300005 ER PT J AU KHERALUWALA, MH GASCOIGNE, RW DIVAN, DM BAUMANN, ED AF KHERALUWALA, MH GASCOIGNE, RW DIVAN, DM BAUMANN, ED TI PERFORMANCE CHARACTERIZATION OF A HIGH-POWER DUAL ACTIVE BRIDGE DC-TO-DC-CONVERTER SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article AB This paper describes the performance of a high-power, high-power-density dc-to-dc converter based on the single-phase dual active bridge (DAB) topology [1]. The dual active bridge converter was shown to have very attractive features in terms of low device and component stresses, small filter components, low switching losses (by virtue of zero voltage switching), high-power density and high efficiency, bidirectional power flow, buck-boost operation, and low sensitivity to system parasitics. For high-output voltages, in the order of kilovolts, a cascaded output structure is considered. The impact of snubber capacitance and magnetizing inductance on the soft switching region of control are discussed. Various control schemes are outlined. Since the leakage inductance of the transformer is used as the main energy transfer element, coaxial transformer design techniques [2] have been utilized to carefully control this parameter. The actual layout and experimental performance of a prototype 50-kW, 50-kHz unit operating with an input voltage of 200 Vdc and an output voltage of 1600 Vdc is presented. C1 UNIV WISCONSIN,DEPT ELECT & COMP ENGN,MADISON,WI 53706. NASA,LEWIS RES CTR,CLEVELAND,OH 44135. RP KHERALUWALA, MH (reprint author), GE,CORP RES & DEV,SCHENECTADY,NY 12301, USA. NR 11 TC 328 Z9 346 U1 2 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD NOV-DEC PY 1992 VL 28 IS 6 BP 1294 EP 1301 DI 10.1109/28.175280 PG 8 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA KB744 UT WOS:A1992KB74400008 ER PT J AU BARAM, Y SALEE, D AF BARAM, Y SALEE, D TI LOWER BOUNDS ON THE CAPACITIES OF BINARY AND TERNARY NETWORKS STORING SPARSE RANDOM VECTORS SO IEEE TRANSACTIONS ON INFORMATION THEORY LA English DT Article DE NEURAL NETWORKS; ASSOCIATIVE MEMORY; STORAGE CAPACITY; SPARSE CODING ID NEURAL NETWORKS; ASSOCIATIVE MEMORY AB It is shown that the memory capacity of networks of binary neurons storing, by the so-called Hebbian rule, sparse random vectors over {0, 1}N, is at least c(N / p log N), where c is a positive scalar involving input error probabilities and p is the probability of an element being nonzero. A similar bound is derived for networks of ternary neurons, storing sparse vectors over {-1, 0, 1}N. These results, pertaining to stability and error correction with probability tending to one as the number of neurons tends to infinity, generalize and extend previously known capacity bounds for binary networks storing vectors of equally probable {+/-1} bits. Lower bounds on the capacities of binary and ternary networks of finite sizes are also derived. These bounds suggest critical network sizes that guarantee high gains in capacity per neuron for given sparsities. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RP BARAM, Y (reprint author), TECHNION ISRAEL INST TECHNOL,DEPT COMP SCI,IL-32000 HAIFA,ISRAEL. NR 16 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9448 J9 IEEE T INFORM THEORY JI IEEE Trans. Inf. Theory PD NOV PY 1992 VL 38 IS 6 BP 1633 EP 1647 DI 10.1109/18.165439 PG 15 WC Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA JV466 UT WOS:A1992JV46600001 ER PT J AU CHAO, CC MCELIECE, RJ SWANSON, L RODEMICH, ER AF CHAO, CC MCELIECE, RJ SWANSON, L RODEMICH, ER TI PERFORMANCE OF BINARY BLOCK-CODES AT LOW SIGNAL-TO-NOISE RATIOS SO IEEE TRANSACTIONS ON INFORMATION THEORY LA English DT Article DE BLOCK CODES; ADDITIVE WHITE GAUSSIAN NOISE CHANNEL; LOW SIGNAL-TO-NOISE RATIOS; ERROR PROBABILITIES; CODING GAIN AB The performance of general binary block codes on an unquantized additive white Gaussian noise (AWGN) channel at low signal-to-noise ratios is considered. Expressions are derived for both the block-error and the bit-error probabilities near the point where the bit signal-to-noise ratio is zero. These expressions depend on the global geometric structure of the code, although the minimum distance still seems to play a crucial role. Examples of codes such as orthogonal codes, biorthogonal codes, the (24,12) extended Golay code, and the (15,6) expurgated BCH code are discussed. The asymptotic coding gain at low signal-to-noise ratios is also studied. C1 CALTECH,DEPT ELECT ENGN,PASADENA,CA 91125. JET PROP LAB,PASADENA,CA 91109. RP CHAO, CC (reprint author), NATL TSING HUA UNIV,DEPT ELECT ENGN,HSINCHU 30043,TAIWAN. NR 11 TC 7 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9448 J9 IEEE T INFORM THEORY JI IEEE Trans. Inf. Theory PD NOV PY 1992 VL 38 IS 6 BP 1677 EP 1687 DI 10.1109/18.165442 PG 11 WC Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA JV466 UT WOS:A1992JV46600004 ER PT J AU MURTHY, CA PAL, SK AF MURTHY, CA PAL, SK TI BOUNDS FOR MEMBERSHIP FUNCTIONS - A CORRELATION-BASED APPROACH SO INFORMATION SCIENCES LA English DT Article ID FUZZY AB The paper describes a mathematical formulation for defining bounds for S-type membership functions using correlation [1]. These bounds impose restrictions on variation in the values of membership functions. The significance of these bounds in the image processing/analysis problems has been extensively studied on various images. It has been observed that membership functions satisfying the bounds can provide desirable results. It is also found that Zadeh's standard S-function [2] satisfies these bounds. C1 NASA,LYNDON B JOHNSON SPACE CTR,DIV INFORMAT TECHNOL,SOFTWARE TECHNOL BRANCH,HOUSTON,TX 77058. RP MURTHY, CA (reprint author), INDIAN STAT INST,ELECTR & COMMUN SCI UNIT,CALCUTTA 700035,W BENGAL,INDIA. NR 10 TC 4 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0020-0255 J9 INFORM SCIENCES JI Inf. Sci. PD NOV 1 PY 1992 VL 65 IS 1-2 BP 143 EP 171 DI 10.1016/0020-0255(92)90081-I PG 29 WC Computer Science, Information Systems SC Computer Science GA HZ566 UT WOS:A1992HZ56600007 ER PT J AU PARK, JS HAN, JC HUANG, Y OU, S BOYLE, RJ AF PARK, JS HAN, JC HUANG, Y OU, S BOYLE, RJ TI HEAT-TRANSFER PERFORMANCE COMPARISONS OF 5 DIFFERENT RECTANGULAR CHANNELS WITH PARALLEL ANGLED RIBS SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article ID FRICTION; TUBES AB This paper systematically presents the results of heat transfer and friction factor data measured in five short rectangular channels with turbulence promoters. The project investigated the combined effects of the channel aspect ratio, rib angle-of-attack, and flow Reynolds number on heat transfer and pressure drop in rectangular channels with two opposite ribbed walls. The channel aspect ratio (width-to-height, W/H, ribs on side W) varied from 1/4 to 1/2, to 1, 2, and 4, while the corresponding rib angles-of-attack alpha were 90-degrees, 60-degrees, 45-degrees, and 30-degrees, respectively. The Reynolds number range was 10,000,000. The results suggest that the narrow aspect ratio channels (W/H < 1) give much better heat transfer performance than the wide aspect ratio channels (W/H > 1). For the square channel (W/H = 1), the 60-degrees/45-degrees angled ribs provide the best heat transfer performance. For the narrow aspect ratio channel (W/H = 1/4 or 1/2), the 45-degrees/60-degrees angled ribs are recommended while the 30-degrees/45-degrees angled ribs are better for wide aspect ratio channels (W/H = 4 or 2). C1 NASA,LEWIS RES CTR,HEAT TRANSFER FUNDAMENTALS SECT,CLEVELAND,OH 44135. RP PARK, JS (reprint author), TEXAS A&M UNIV SYST,DEPT MECH ENGN,TURBINE HEAT TRANSFER LAB,COLL STN,TX 77843, USA. NR 25 TC 145 Z9 150 U1 1 U2 19 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD NOV PY 1992 VL 35 IS 11 BP 2891 EP 2903 DI 10.1016/0017-9310(92)90309-G PG 13 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA KB746 UT WOS:A1992KB74600015 ER PT J AU REMER, DS SHERIF, JS BUCHANAN, HR AF REMER, DS SHERIF, JS BUCHANAN, HR TI MODELING THE DEEP SPACE NETWORK COSTS FOR FUTURE SPACE MISSIONS BY USING MAJOR COST DRIVERS SO INTERNATIONAL JOURNAL OF PRODUCTION ECONOMICS LA English DT Article AB This paper develops a cost model to do long range planning cost estimates for Deep Space Network (DSN) support of future space missions. The model is a function of eight major mission cost drivers such as uplink frequency upgrade (U/L), telemetry upgrade (TEL) and antenna gain/noise temperature (G/T) upgrade. This paper focuses on the costs required to modify and/or enhance the DSN to prepare for supporting future space missions. Two models are derived from actual cost data from three space missions: Voyager (Uranus), Voyager (Neptune), and Magellan. Model A allows you to estimate the total cost, and Model B allows you to estimate the time profile cost and total cost for DSN support of a similar future space mission. The models were back tested against the total cost and the time profile cost for DSN support of three projects, Voyager (U), Voyager (N) and Magellan, and gave cost estimates which range from 17% below to 19% above actual costs for Model A, and 22.5% below to 17.5% above for Model B. The total cost Model A was also applied to estimate the total costs for DSN support of two other independent projects: Mariner Jupiter/Saturn (MJS - later became Voyager), and Viking. This model gave total cost estimates for DSN support which range from 15% to 4% above actual total costs for MJS and Viking, respectively. RP REMER, DS (reprint author), JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-5273 J9 INT J PROD ECON JI Int. J. Prod. Econ. PD NOV PY 1992 VL 28 IS 2 BP 193 EP 202 DI 10.1016/0925-5273(92)90031-2 PG 10 WC Engineering, Industrial; Engineering, Manufacturing; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA KD213 UT WOS:A1992KD21300006 ER PT J AU RIZK, YM GEE, K AF RIZK, YM GEE, K TI UNSTEADY SIMULATION OF VISCOUS FLOWFIELD AROUND F-18 AIRCRAFT AT LARGE INCIDENCE SO JOURNAL OF AIRCRAFT LA English DT Article AB This article describes the numerical simulation of the unsteady viscous flow around the F-18 aircraft at high angles of attack. A generalized overset zonal grid scheme is used to decompose the computational space around the complete aircraft, included deflected control surfaces. The grids around various components of the aircraft are created numerically using a three-dimensional hyperbolic grid generation procedure. The Reynolds-averaged Navier-Stokes equations are integrated using a time-accurate, implicit procedure. Results for the turbulent flow around the F-18 aircraft at 30 deg angle of attack show the details of the flowfield structure, including the unsteadiness created by the vortex burst and the resulting fluctuating airloads exerted on the vertical tail. The computed results agree fairly well with flight data for surface pressure, surface flow pattern, vortex burst location, and the dominant frequency for tail load fluctuations. RP RIZK, YM (reprint author), NASA,AMES RES CTR,MOFFETT FIELD,CA 94035, USA. NR 0 TC 10 Z9 10 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD NOV-DEC PY 1992 VL 29 IS 6 BP 986 EP 992 DI 10.2514/3.56862 PG 7 WC Engineering, Aerospace SC Engineering GA KB465 UT WOS:A1992KB46500003 ER PT J AU NORUM, TD AF NORUM, TD TI GROUND IMPINGEMENT NOISE OF SUPERSONIC JETS FROM NOZZLES WITH VARIOUS EXIT GEOMETRIES SO JOURNAL OF AIRCRAFT LA English DT Article AB Acoustic measurements of single and twin free- and impinging-jets were made for circular convergent and convergent-divergent (CD) nozzles, rectangular CD nozzles, and D-shaped convergent nozzles. The measured free-jet screech tone frequencies agree with existing theory. Noise due to jet impingement correlates on the basis of the nozzle-to-ground distance relative to the free-jet shock structure, with the highest sound pressure levels generally due to jet impingement tones. All nozzle types experienced near-field overall sound pressure levels of 160 dB at some nozzle-to-ground distances, including the CD nozzles operating at their design pressure. The effect of the second jet was to sometimes increase levels due to twin jet resonance and at other times reduce levels resulting from either suppression of the screech/impingement feedback process, or more simply, by acoustic interference of the noise produced by the two jets. RP NORUM, TD (reprint author), NASA,LANGLEY RES CTR,DIV ACOUST,HAMPTON,VA 23665, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD NOV-DEC PY 1992 VL 29 IS 6 BP 993 EP 998 DI 10.2514/3.46275 PG 6 WC Engineering, Aerospace SC Engineering GA KB465 UT WOS:A1992KB46500004 ER PT J AU VICROY, DD AF VICROY, DD TI ASSESSMENT OF MICROBURST MODELS FOR DOWNDRAFT ESTIMATION SO JOURNAL OF AIRCRAFT LA English DT Article AB NASA has been conducting research in the development of technologies for forward-looking, airborne, wind shear detection systems. Doppler RADAR and LIDAR are two of the technologies being tested to provide this capability. Both measure the Doppler shift from aerosols, raindrops, and other debris in the air to determine the "line-of-sight" relative velocity of the air. An inherent limitation of this type of system is its inability to measure velocities perpendicular to the line-of-sight. This limitation can result in significant underestimation of the magnitude of wind shear hazard. One solution to this line-of-sight limitation of Doppler type sensors, is to use a theoretical or empirical model of a microburst to estimate the perpendicular velocities from the measured line-of-sight values. This article is a summary of an analytical study to assess the effectiveness of three microburst models in estimating the downdraft from horizontal velocity measurements. The article discusses the development of the models and their characteristics. The models are tested at different stages in the life cycle of a microburst. RP VICROY, DD (reprint author), NASA,LANGLEY RES CTR,VEHICLE OPERAT RES BRANCH,MS 156A,HAMPTON,VA 23665, USA. NR 0 TC 41 Z9 54 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD NOV-DEC PY 1992 VL 29 IS 6 BP 1043 EP 1048 DI 10.2514/3.46282 PG 6 WC Engineering, Aerospace SC Engineering GA KB465 UT WOS:A1992KB46500011 ER EF