FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Stanton, TP Law, CS Watson, AJ AF Stanton, TP Law, CS Watson, AJ TI Physical evolution of the IronEx-I open ocean tracer patch SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID PACIFIC AB An 8 x 8 km tracer-enriched patch was successfully formed in an open-ocean mixed layer in the equatorial Pacific during the first uncontained test of the iron hypothesis. To minimize the effects of horizontal advection, the patch formation and subsequent rapid underway sampling of the patch properties were performed in a Lagrangian reference frame centered on a navigated, drogued buoy that tracked the mixed layer movements on O(1 d) timescales. Daily maps of the evolving patch shape, and corrections for the buoy drift relative to the patch center, were based on objectively analyzed surface concentration maps of an inert tracer, SF6, which had been injected into the ocean surface with trace quantities of iron during the patch formation. The Lagrangian reference frame significantly reduced large scale circular and lateral advection errors in maps of the surface patch shape. A strong pycnocline at approximately 35 m depth and very constant 6 m s(-1) wind forcing greatly limited turbulent diffusion below the mixed layer. Rapid small scale mixing over the first 24 h was followed by a four day period of slow spreading, primarily in the along-wind direction. Estimates of along wind horizontal diffusivity using a Fickian model were 600 +/- 100 m(2) s(-1), with a mean cross wind value of 200 +/- 30 m(2) s(-1) over a 4 d period. On the fifth day an intruding low salinity surface front effectively capped the patch between a 10-20 m thick fresh surface layer and the pycnocline. This experiment demonstrated that an O(100 km(2)) open ocean mixed layer tracer tagged patch could be formed, and its evolution mapped the presence of advection over 5-10 d periods. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. Plymouth Marine Lab, Plymouth PL1 3DH, Devon, England. RP Stanton, TP (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 13 TC 23 Z9 23 U1 2 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 6 BP 947 EP + DI 10.1016/S0967-0645(98)00018-6 PG 28 WC Oceanography SC Oceanography GA 137ZG UT WOS:000076946500003 ER PT J AU Law, CS Watson, AJ Liddicoat, MI Stanton, T AF Law, CS Watson, AJ Liddicoat, MI Stanton, T TI Sulphur hexafluoride as a tracer of biogeochemical and physical processes in an open-ocean iron fertilisation experiment SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID SULFUR-HEXAFLUORIDE; EQUATORIAL PACIFIC; SEA-WATER; SEAWATER AB The first open-ocean experiment to test the iron hypothesis in the equatorial Pacific was undertaken using the tracer gas sulphur hexafluoride (SF6) to locate and track the fertilised surface water. Continuous surface measurements showed that the SF6 patch spread rapidly in the first 24 h, from an initial release area of similar to 64 km(2) to a total area of 214 km(2), and remained relatively constant in size for the following three-day period. SF6 data was mapped in a Lagrangian frame of reference by the use of a drogued GPS buoy released at the centre of the patch. The SF6 patch remained coherent and exhibited a slow, anti-cyclonic oscillation during the first four days. The buoy was transported downwind of the patch in a northwesterly direction within two days, which has implications for the future use of buoys in surface-water advection studies. Following subduction below a low-salinity front 3-4 days after release, the patch centre was relocated by its SF6 signal at a depth of 25-30 m to the east of the residual surface patch. The latter spread rapidly to the southwest during the remainder of the experiment, whilst the subducted patch remained relatively stationary. Density-corrected SF6 profiles were used to calculate a mean vertical eddy diffusivity of 0.25 cm(2)/s across the thermocline following the subduction event. A vertical flux of nitrate of 2.5 mmol/m(-2)d(-1) into the mixed layer was estimated, which implied an f-ratio value of 0.4 on comparison with productivity data. The results demonstrate that SF6 is a successful tracer of water masses, and emphasise the potential of this technique for the in situ measurement and manipulation of open-ocean processes. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Plymouth Marine Lab, Plymouth PL1 3DH, Devon, England. USN, Postgrad Sch, Monterey, CA 93943 USA. RP Law, CS (reprint author), Plymouth Marine Lab, Prospect Pl,W Hoe, Plymouth PL1 3DH, Devon, England. NR 31 TC 63 Z9 63 U1 2 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 6 BP 977 EP 994 DI 10.1016/S0967-0645(98)00022-8 PG 18 WC Oceanography SC Oceanography GA 137ZG UT WOS:000076946500004 ER PT J AU Steger, JM Collins, CA Chu, PC AF Steger, JM Collins, CA Chu, PC TI Circulation in the Archipielago de Colon (Galapagos Islands), November, 1993 SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID EQUATORIAL PACIFIC; OCEAN AB ADCP and CTD data are used to investigate the circulation pattern in the region of the Archipielago de Colon during the period 8-21 November 1993. Surface flow was dominated by the westward flowing South Equatorial Current except in a small region to the west of Isla Fernandina, where eastward flow associated with the shoaling of the Equatorial Undercurrent was observed. The Equatorial Undercurrent was observed to the west of the Archipelago, centered along 0.5 degrees S at 70 m with peak velocities similar to 0.6 ms(-1) and, at 92 degrees W, a transport of 6.6 Sv. Between 92 degrees W and the Archipielago, a distance of only 40 km, the Undercurrent surfaced, the eastward flow decelerated, and meridional flow diverged on either side of 0.5 degrees S, the southward flow appearing to be stronger and better developed than the northward flow. At 89 degrees W the Undercurrent and its associated salinity maximum were observed at 50 m depth at 1 degrees S, with greatly reduced speed, 0.2 ms(-1); subsurface eastward flow also appeared in the northern hemisphere, but this flow was at greater depth, 140 m. The interaction of the Undercurrent and the Archipielago appeared to enhance the thickness of the 16 degrees C thermostad. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Collins, CA (reprint author), USN, Postgrad Sch, Dept Oceanog, Rm 328,833 Dyer Rd, Monterey, CA 93943 USA. NR 22 TC 14 Z9 14 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 6 BP 1093 EP 1114 DI 10.1016/S0967-0645(98)00015-0 PG 22 WC Oceanography SC Oceanography GA 137ZG UT WOS:000076946500010 ER PT J AU Greene, CH Fristrup, KM Stanton, TK Gisiner, R Tipper, RC AF Greene, CH Fristrup, KM Stanton, TK Gisiner, R Tipper, RC TI Bioacoustical oceanography: an introduction SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article C1 Cornell Univ, Ithaca, NY 14853 USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. Off Naval Res, Arlington, VA 22217 USA. RP Greene, CH (reprint author), Cornell Univ, Ithaca, NY 14853 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 7 BP 1151 EP 1153 DI 10.1016/S0967-0645(98)00024-1 PG 3 WC Oceanography SC Oceanography GA 145ZW UT WOS:000077403600001 ER PT J AU Ramp, SR Abbott, CL AF Ramp, SR Abbott, CL TI The vertical structure of currents over the Continental Shelf off Point Sur, CA, during Spring 1990 SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article DE current; vertical structure; upwelling centre ID CALIFORNIA CURRENT SYSTEM; OCEAN DYNAMICS EXPERIMENT; NORTHERN CALIFORNIA; BOUNDARY-LAYER; INNER-SHELF; CIRCULATION; VARIABILITY; BOTTOM; COAST; FLOW AB A 300 kHz acoustic Doppler current profiler (ADCP) was deployed off Point Sur, CA (36 degrees 17.8'N, 121 degrees 59.5'W) from 28 February to 11 May 1990 to study the current response to local and remote forcing over a narrow continental shelf near a coastal promontory. The unit was moored 4 m off the bottom in water 84 m deep, and it profiled the currents in the water column in 4-m depth bins to within 12 m of the surface. The flow can be described in terms of the response to equatorward wind events Versus the response to poleward wind events and wind relaxations. During equatorward wind events, the current Vectors were directed equatorward and offshore near the surface at about 35 cm s(-1), then backed counterclockwise and decreased in magnitude with depth to about 10 cm s(-1), 4 m off the bottom. The vertical current structure during these events was well reproduced using a simple model in which the bottom Ekman layer was added to the unstratified model of Csanady (1982) for the wind-forced setup near a coast. The counterclockwise turning (as opposed to the open-ocean, clockwise sense) resulted from the interior geostrophic component, which overwhelmed the surface Ekman spiral and combined with the bottom Ekman layer to produce the observed vertical structure. The best agreement between the modelled and observed current vectors was obtained using a vertical mixing coefficient of about 12 x 10(-3) m(2) s(-1). During poleward winds and wind relaxations, the currents were northward at about 20 cm s(-1) over most of the water column, then also backed counterclockwise as the bottom was approached. The more barotropic response during the weak poleward winds and wind relaxations showed no evidence for local wind forcing, which suggests forcing due to an alongshore pressure gradient arising from an alongshore surface slope of about 2 x 10(-7). The across-shore mass balance from the best-fit modelled flow held during upwelling events showed that the onshore transport in the lower water column was 2-3 times the offshore transport in the upper water column. This may be due to three-dimensional effects or to the across-shore adjustment drift (Csanady, 1982), which feeds the alongshore geostrophic flow. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Ramp, SR (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 35 TC 10 Z9 10 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 8-9 BP 1443 EP 1470 DI 10.1016/S0967-0645(98)80003-9 PG 28 WC Oceanography SC Oceanography GA 149AB UT WOS:000077582700003 ER PT J AU Steger, JM Collins, CA Schwing, FB Noble, M Garfield, N Steiner, MT AF Steger, JM Collins, CA Schwing, FB Noble, M Garfield, N Steiner, MT TI An empirical model of the tidal currents in the Gulf of the Farallones SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID DOPPLER CURRENT PROFILER; NORTHERN CALIFORNIA; CONTINENTAL-SHELF; OCEAN TIDES; FLOW AB Candela et al. (1990, 1992) showed that tides in an open ocean region can be resolved using velocity data from a ship-mounted ADC-P. We use their method to build a spatially varying model of the tidal currents in the Gulf of the Farallones, an area of complicated bathymetry where the tidal velocities in some parts of the region are weak compared to the mean currents. We describe the tidal fields for the M-2, S-2, K-1, and O-1 constituents and show that this method is sensitive to the model parameters and the quantity of input data. In areas with complex bathymetry and tidal structures, a large amount of spatial data is needed to resolve the tides. A method of estimating the associated errors inherent in the model is described. Published by Elsevier Science Ltd. C1 NOAA, NMFS, Pacific Fisheries Environm Lab, Pacific Grove, CA USA. USN, Postgrad Sch, Monterey, CA USA. USGS, Menlo Park, CA USA. RP Steger, JM (reprint author), NOAA, NMFS, Pacific Fisheries Environm Lab, Pacific Grove, CA USA. NR 44 TC 12 Z9 12 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 8-9 BP 1471 EP 1505 DI 10.1016/S0967-0645(98)80004-0 PG 35 WC Oceanography SC Oceanography GA 149AB UT WOS:000077582700004 ER PT J AU Batteen, ML Vance, PW AF Batteen, ML Vance, PW TI Modeling studies of the effects of wind forcing and thermohaline gradients on the California Current System SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID COASTAL TRANSITION ZONE; SEASONAL VARIABILITY; NORTHERN CALIFORNIA; OCEAN CIRCULATION; VANCOUVER ISLAND; EDDIES; SATELLITE; MEANDERS; EDDY; DYNAMICS AB This process-oriented study uses a high-resolution, multi-level, primitive equation model to study the combined effects of wind forcing and thermohaline gradients on the ocean circulation of the California Current System (CCS). The ocean circulation is generated by the model using a combination of climatological wind stress forcing and thermohaline gradients. In the first experiment, the effects of thermohaline gradients alone are evaluated; in the second experiment, previously conducted, the effects of wind forcing are isolated; while in the third experiment, the combined effects of wind forcing and thermohaline gradients are investigated. The results from the combined experiment show that even though the effects of wind forcing dominate the CCS, the additional effects of thermohaline gradients result in the following: the seasonal development of a poleward surface current and an equatorward undercurrent in the poleward end of the model region; an onshore geostrophic component, which results in a temperature front and stronger surface and subsurface currents between Cape Mendocino and Point Arena; and a region of maximum eddy kinetic energy inshore of similar to 125W between Cape Mendocino and Point Arena, associated with the temperature front. These model simulations are qualitatively similar to recent hydrographic, altimetric, drifter, and moored observations of the CCS. Published by Elsevier Science Ltd. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. EM batteen@oc.nps.navy.mil NR 42 TC 8 Z9 8 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 EI 1879-0100 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 8-9 BP 1507 EP 1556 DI 10.1016/S0967-0645(98)80005-2 PG 50 WC Oceanography SC Oceanography GA 149AB UT WOS:000077582700005 ER PT J AU Weller, RA Baumgartner, MF Josey, SA Fischer, AS Kindle, JC AF Weller, RA Baumgartner, MF Josey, SA Fischer, AS Kindle, JC TI Atmospheric forcing in the Arabian Sea during 1994-1995: observations and comparisons with climatology and models SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID WIND STRESS; OCEAN; SURFACE; METEOROLOGY; BUDGET AB Accurate, year-long time series of winds, incoming shortwave and longwave radiation, air and sea temperatures, relative humidity, barometric pressure, and precipitation were collected from a surface mooring deployed off the coast of Oman along the climatological axis of the Findlater Jet from October 1994 to October 1995. Wind stress, heat flux, and freshwater flux were computed using bulk formulae. The Northeast Monsoon was characterized by steady but moderate winds, clear skies, relatively dry air, and two months, December and January, in which the ocean, on average, lost 45 Wm(-2) to the atmosphere. The Southwest Monsoon had strong winds, cloudy skies, and moist air. Because of reduced latent and longwave heat loss, it was accompanied by sustained oceanic heat gain, with the strongest monthly mean warming, 147 Wm(-2), in August. Large differences are found between the observations and older climatologies. Recent climatologies agree better with the observations. The means of the Southampton Oceanography Center climatology for 1980-1995 are close to the buoy monthly means. Monthly means from that climatology show that 1994-1995 was in general a typical year, with surface meteorology and air-sea fluxes within one standard deviation of the long term means. Concurrent data from the NCEP, ECMWF, and FNMOC show that the models provide realistic surface winds. FNMOC winds show that the timing and character of the onset of the Southwest Monsoon in 1995 differed from 1994 and 1996 when variability within one month is resolved. The models fail to replicate other observed surface meteorology and to produce realistic heat fluxes. Annual and monsoonal mean net heat fluxes from the models differed from those of the buoy by 50 to 80 Wm(-2). Because of these differences, some care is warranted in selecting and using air-sea flux fields in studies of the Arabian Sea. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. Southampton Oceanog Ctr, Southampton SO14 3ZH, Hants, England. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Weller, RA (reprint author), Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. EM rweller@whoi.edu NR 34 TC 178 Z9 181 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 10-11 BP 1961 EP 1999 DI 10.1016/S0967-0645(98)00060-5 PG 39 WC Oceanography SC Oceanography GA 152FF UT WOS:000077765000003 ER PT J AU Millero, FJ Degler, EA O'Sullivan, DW Goyet, C Eischeid, G AF Millero, FJ Degler, EA O'Sullivan, DW Goyet, C Eischeid, G TI The carbon dioxide system in the Arabian Sea SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID DISSOCIATION-CONSTANTS; SEAWATER; ACID; DENITRIFICATION; THERMODYNAMICS; CALIBRATION; ALKALINITY; TITRATION; MARINE; OCEANS AB In 1995 the WHOI (C. Goyet) and MIAMI (F.J. Miliero) groups participated on a number of research cruises in the Arabian Sea as part of the U.S. Joint Global Ocean Flux Study (JGOFS) sponsored by the National Science Foundation (NSF). This paper gives the results of our total inorganic carbon dioxide (TCO2), total alkalinity (TA) and potentiometric pH measurements made on Arabian Sea water samples during these cruises. Measurements made on Certified Reference Material (CRM) indicate that the reproducibility of the measurements was +/- 0.007 in pH, +/- 3.2 mu mol kg(-1) in TA, and +/- 1.2 mu molkg(-1) in TCO2 (N = 180). The surface measurements (0-30 m) of pH and normalized TCO2, and TA were quite uniform throughout the year (pH = 8.1 +/- 0.05, NTCO2 = 1950 +/- 20 mu molkg(-1) and NTA = 2290 +/- 5 mu molkg(-1)). The larger variations in NTCO2 in the surface waters are related to changes in primary production and upwelling in the coastal waters. The depth profiles of pH, pCO(2), TA, and TCO2 were similar to those in the Equatorial Pacific Ocean. The components of the carbonate system (CO2, HCO3-, CO32-) and the saturation state (Omega) for calcite and aragonite were determined from the measurements of TA and TCO2. The waters below 600 and 3400 m in the Arabian Sea were undersaturated (Omega < 1.0) for aragonite and calcite, respectively. The CO2 measurements have been combined with the nutrient data to examine the stoichiometric ratios of C/N, C/P, C/O-2, and C/SiO2 of the waters. Marked differences were found for the waters above and below the oxygen minimum zone. The surface water results have been used to develop the following stoichiometry for phytoplankton in the Arabian Sea (CH2O)(125)(NH3)(14)(H3PO4)(SiO2)(13). The oxidation of this material is due to reactions with O-2 (77%) and NO3 (23%) with the resultant formation of N-2 and N2O. The maximum amount of organic carbon oxidized has been estimated to be 3.1 mu molkg(-1) in the deep waters with as much as 0.9 mu molkg(-1) in the oxygen minimum zone with NO3. The maximum amount of CaCO3 dissolved in the deep waters is 116 mu molkg(-1). These results, together with the organic material collected from the sediment traps, should be useful in characterizing the formation and degradation of plant material in the Arabian Sea. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. RP Millero, FJ (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, 4600 Rickenbacker Causeway, Miami, FL 33149 USA. EM fmillero@rsmas.miami.edu OI O'Sullivan, Daniel/0000-0001-9104-5703 NR 32 TC 45 Z9 52 U1 1 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 1998 VL 45 IS 10-11 BP 2225 EP 2252 DI 10.1016/S0967-0645(98)00069-1 PG 28 WC Oceanography SC Oceanography GA 152FF UT WOS:000077765000011 ER PT J AU Pearton, SJ Wilson, RG Zolper, JC Zavada, JM AF Pearton, SJ Wilson, RG Zolper, JC Zavada, JM TI Diffusion of dopants and impurities in GaN and related materials SO DEFECT AND DIFFUSION FORUM LA English DT Article DE redistribution; hydrogen; annealing ID MOLECULAR-BEAM EPITAXY; III-V-MATERIALS; ION-IMPLANTATION; HYDROGENATION; FILMS; COMPENSATION; GROWTH; GAAS; INN; MG AB The redistribution of dopant and impurity species in GaN, AlN and InN was investigated for rapid thermal or furnace annealing conditions. The dopants show minimal diffusion even at high temperatures characteristic of implant activation, while atomic hydrogen is also quite stable in these materials. The results emphasize the potential of the III-nitrides for high power, high temperature electronics. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Off Naval Res, Arlington, VA 22217 USA. USA, Res Off, Res Triangle Pk, NC 27709 USA. RI Schaff, William/B-5839-2009 NR 32 TC 0 Z9 0 U1 2 U2 4 PU TRANS TECH-SCITEC PUBLICATIONS LTD PI UETIKON A.S. PA BRANDRAIN 6, CH-8707 UETIKON A.S., SWITZERLAND SN 1012-0386 J9 DEFECT DIFFUS FORUM PY 1998 VL 159 BP 63 EP 81 PG 19 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA ZV985 UT WOS:000074362100004 ER PT J AU Walters, RJ AF Walters, RJ TI The annealing behavior of irradiated diffused junction and epitaxial InP solar cells SO DEFECT AND DIFFUSION FORUM LA English DT Article DE radiation effects; deep level transient spectroscopy; defect annealing ID CHEMICAL VAPOR-DEPOSITION; RADIATION-RESISTANCE; ELECTRON; DEGRADATION; ENERGY AB A detailed analysis of the annealing characteristics following irradiation of InP solar cells grown by thermal diffusion are compared to that of InP cells grown by vapor phase epitaxy. Deep Level Transient Spectroscopy (DLTS) is used to characterize the radiation-induced defects and to monitor the evolution of the defects during the annealing experiments. Current vs. voltage (IV) measurements under simulated solar light are used to characterize the electrical performance of the cells. Annealing due to minority carrier injection at and below room temperature is studied, as well has thermal annealing at temperatures up to 650K. While essentially the same radiation-induced defect spectrum is measured in both cell types, the diffused junction solar cells display significantly more recovery than the epitaxial cells. This enhanced recovery is shown to be due the removal of the majority carrier trap labeled H5 and the minority carrier traps in the diffused-junction cells. The cause for the difference in annealing behavior between the cell types is investigated in terms of the affect of the different cell structures on the defect mobility. C1 USN, Res Lab, Washington, DC 20375 USA. EM rwalters@ccf.nrl.navy.mil NR 18 TC 0 Z9 0 U1 0 U2 0 PU TRANS TECH-SCITEC PUBLICATIONS LTD PI UETIKON A.S. PA BRANDRAIN 6, CH-8707 UETIKON A.S., SWITZERLAND SN 1012-0386 J9 DEFECT DIFFUS FORUM PY 1998 VL 159 BP 125 EP 132 PG 8 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA ZV985 UT WOS:000074362100008 ER PT S AU Grun, J Manka, CK Hoffman, CA Meyer, JR Glembocki, OJ Qadri, SB Skelton, EF Donnelly, D Covington, B AF Grun, J Manka, CK Hoffman, CA Meyer, JR Glembocki, OJ Qadri, SB Skelton, EF Donnelly, D Covington, B BE Ashok, S Chevallier, J Sumino, K Sopori, BL Gotz, W TI Athermal annealing of silicon SO DEFECT AND IMPURITY ENGINEERED SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Defect and Impurity Engineered Semiconductors II at the Materials-Research-Society Spring Meeting CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc, Bunko Keiki, Fujitsu, Hewlett Packard Co, Hughes Res Lab, Jobin Yvon, Kodak Res Lab, Komatsu Electr Met, Mattson Technol, MEMC Electr Mat, Mitsubishi Mat Silicon, Natl Renewable Energy Lab, NEC, Nippon Steel, Photowatt, Riber, Shin Etsu Handotal, Sumitomo Sitix AB We experimentally demonstrate the annealing and electrical activation of doped silicon without the direct application of heat as in conventional thermal annealing or pulsed laser annealing. 25 x 25 x 3 mm samples of silicon doped by neutron transmutation were irradiated with a short pulse from a 1.06-micron laser. The few joule laser pulse was focused to mm-diameter surface spot which resulted in high power (similar to 10(11) W/cm(2)) capable of launching shocks into the entire sample. In a few instances the entire silicon slab, including regions far outside the illuminated spot, was annealed and electrically activated. In the annealed samples electrical activation of donors throughout the slab, measured with a four-point probe, was uniform and comparable to that of thermally annealed control samples. Far-infrared spectroscopy and Hall measurements also showed that the donor species was activated and Raman spectroscopy demonstrated marked improvement in the crystal structure. We conjecture that the annealing was caused by the mechanical energy that was launched into the slab by the laser pulse. Results of experiments on an ion-implanted silicon sample are also discussed. C1 USN, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. RP Grun, J (reprint author), USN, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-416-5 J9 MATER RES SOC SYMP P PY 1998 VL 510 BP 395 EP 402 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Engineering; Materials Science GA BL88A UT WOS:000077031700056 ER PT S AU Matthews, AD Arrieta, LL AF Matthews, AD Arrieta, LL BE Dubey, AC Harvey, JF Broach, JT TI Acoustic-optic hybrid imaging experiment SO DETECTION AND REMEDIATION TECHNOLOGIES FOR MINES AND MINELIKE TARGETS III, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Detection and Remediation Technologies for Mines and Minelike Targets III CY APR 13-17, 1998 CL ORLANDO, FL SP SPIE AB An experiment series to determine the ability of laser vibrometers to receive and process echoes from the water surface culminates in a 28 inch by 28 inch aperture synthesis. Highly resolved three dimensional imagery of a submerged three liter beverage bottle, suspended in the free field is presented. Excitation is accomplished by a submerged acoustic source transmitting a swept FM pulse near 70 kilohertz with a 10 kilohertz sweep. The receive laser head is suspended 19 inches above the water surface, and moved by an inverted x-y positioning table to create a three dimensional synthetic aperture. Temporal oversampling and common trigger for transmitter and data acquisition system are used to establish coherence. In an effort to better resolve the target, the aperture is made larger than previous attempts. Experiment results are reported. C1 USN, Ctr Surface Warfare, Coastal Syst Stn, Dahlgren Div, Panama City, FL 32407 USA. RP Matthews, AD (reprint author), USN, Ctr Surface Warfare, Coastal Syst Stn, Dahlgren Div, 6703 W Highway 98, Panama City, FL 32407 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2841-8 J9 PROC SPIE PY 1998 VL 3392 BP 187 EP 192 DI 10.1117/12.324190 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL85T UT WOS:000076961000019 ER PT S AU Howarth, TR AF Howarth, TR BE Dubey, AC Harvey, JF Broach, JT TI Broadband acoustic projector for low-frequency synthetic aperture sonar application SO DETECTION AND REMEDIATION TECHNOLOGIES FOR MINES AND MINELIKE TARGETS III, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Detection and Remediation Technologies for Mines and Minelike Targets III CY APR 13-17, 1998 CL ORLANDO, FL SP SPIE DE piezocomposite; broadband; transducer; projector; multilayer; SAS; MR/H AB possibilities for increased mine detection and classification techniques have established a need for broadband, underwater acoustic projectors. An advanced version of a low frequency synthetic aperture sonar (SAS)for the mine reconnaissance hunter program has recently been developed. The transducer is resonant at 100 kHz but has been designed to deliver constant high sound pressure levels over an operating frequency range of 10 kHz to 100 kHz. This wide band operation is accomplished because of an absence of spurious modes within the operational frequency decade. The actual projector is constructed with a two layered 1-3 piezocomposite material stacked in mechanical series and electrically wired in parallel. This arrangement was selected in order to maximize the source level output. The center electrode of the monolithic 1-3 piezocomposite layers has been segmented to offer four individual elements such that combinations of the sectors offer the ability to access nine different apertures. A constant source level is maintained through the use of a preshaped transformer between the driver and the projector. The combination of the transformer design with the clean spectrum response of the composite material results in an acoustic projector with constant source level. C1 USN, Res Lab, Acoust Div, Washington, DC 20375 USA. RP Howarth, TR (reprint author), USN, Res Lab, Acoust Div, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2841-8 J9 PROC SPIE PY 1998 VL 3392 BP 193 EP 202 DI 10.1117/12.324191 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL85T UT WOS:000076961000020 ER PT S AU Szymczak, WG Guo, WM Rogers, JCW AF Szymczak, WG Guo, WM Rogers, JCW BE Dubey, AC Harvey, JF Broach, JT TI Mine detection using variational methods for image enhancement and feature extraction SO DETECTION AND REMEDIATION TECHNOLOGIES FOR MINES AND MINELIKE TARGETS III, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Detection and Remediation Technologies for Mines and Minelike Targets III CY APR 13-17, 1998 CL ORLANDO, FL SP SPIE DE variational methods; multichannel segmentation; image processing; feature extraction; clutter removal; classification; side-scan sonar; laser line-scan AB A critical part of automatic classification algorithms is the extraction of features which distinguish targets from background noise and clutter. The focus of this paper is the use of variational methods for improving the classification of sea mines from both side-scan sonar and laser line-scan images. These methods are based on minimizing a functional of the image intensity. Examples include Total Variation Minimization (TVM) which is very effective for reducing the noise of an image without compromising its edge features, and Mumford-Shah segmentation, which in its simplest form, provides an optimal piecewise constant partition of the image. For the sonar side-scan images it is shown that a combination of these two variational methods, (first reducing the noise using TVM, then using segmentation) outperforms the use of either one individually for the extraction of minelike features. Multichannel segmentation based on a wavelet decomposition is also effectively used to declutter a sonar image. Finally, feature extraction and classification using segmentation is demonstrated on laser line-scan images of mines in a cluttered sea floor. C1 USN, Res Lab, Washington, DC 20375 USA. RP Szymczak, WG (reprint author), USN, Res Lab, Code 7131, Washington, DC 20375 USA. EM szymczak@eeyore.nrl.navy.mil NR 0 TC 10 Z9 10 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2841-8 J9 PROC SPIE PY 1998 VL 3392 BP 286 EP 296 DI 10.1117/12.324200 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL85T UT WOS:000076961000029 ER PT S AU McGill, RA Mlsna, TE Chung, R Nguyen, VK Stepnowski, J Abraham, MH Kobrin, P AF McGill, RA Mlsna, TE Chung, R Nguyen, VK Stepnowski, J Abraham, MH Kobrin, P BE Dubey, AC Harvey, JF Broach, JT TI Sorbent coatings for nitroaromatic vapors: Applications with chemical sensors SO DETECTION AND REMEDIATION TECHNOLOGIES FOR MINES AND MINELIKE TARGETS III, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Detection and Remediation Technologies for Mines and Minelike Targets III CY APR 13-17, 1998 CL ORLANDO, FL SP SPIE AB The solubility properties of a series of nitroaromatic compounds have been determined and utilized with known linear solvation energy relationships to calculate their sorption properties in a series of chemoselective polymers. These measurements and results were used to design a series of novel chemoselective polymers to target polynitroaromatic compounds The polymers have been evaluated as thin sorbent coatings on surface acoustic wave (SAW) devices for their vapor sorption and selectivity properties. The most promising materials tested, include siloxane polymers functionalized with acidic pendant groups that are complimentary in their solubility properties for nitroaromatic compounds. The most sensitive of the new polymers exhibit SAW sensor detection limits for nitrobenzene and 2,4-dinitrotoluene at 3 parts per billion (ppb) and 235 parts per trillion (ppt) respectively. Optimized polymers exhibit low water vapor sorption, and rapid signal kinetics for nitrobenzene, reaching 90% of signal response in 4 seconds. Studies with an in-situ infra-red spectroscopy technique are used to determine the mechanism of interaction between nitroaromatic compounds and the chemoselective polymer. C1 USN, Res Lab, Washington, DC 20375 USA. RP McGill, RA (reprint author), USN, Res Lab, Code 6670, Washington, DC 20375 USA. EM amcgill@ccf.nrl.navy.mil NR 0 TC 11 Z9 11 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2841-8 J9 PROC SPIE PY 1998 VL 3392 BP 384 EP 389 DI 10.1117/12.324210 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL85T UT WOS:000076961000038 ER PT S AU Smith, CM Tuovila, SM Nelson, SR AF Smith, CM Tuovila, SM Nelson, SR BE Dubey, AC Harvey, JF Broach, JT TI Identification of mines in enhanced electro-optic images SO DETECTION AND REMEDIATION TECHNOLOGIES FOR MINES AND MINELIKE TARGETS III, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Detection and Remediation Technologies for Mines and Minelike Targets III CY APR 13-17, 1998 CL ORLANDO, FL SP SPIE DE mine warfare; mine identification; electro-optic imagery; shallow water; image enhancement AB Electro-optic (EO) sensors can be used for mine identification in turbid shallow water and very shallow water domains in which spatially- and temporally- variant conditions severely limit the effectiveness of acoustic and visual sensors. Also, EO sensors produce images with significantly finer resolution than acoustic sensors, making identification of mines possible rather than just classification of minelike targets. This paper presents image processing and enhancement techniques that improve mine identification probability. Due to the large variation in brightness, contrast, and texture across EO images, virtually all processing performed on these images must be local in nature. In an effort to compensate for the differences in image quality, several preprocessing techniques for noise reduction and contrast enhancement are applied to the images. A texture analysis is performed on the enhanced images in an effort to locate likely man-made surfaces. Of particular interest, the SUSAN (Smallest Univalue Segment Assimilating Nucleus) principle is investigated as a tool for both image enhancement and texture analysis. The performance of this technique, recently introduced by researchers from Oxford University, is compared with that of more traditional methods. The incompatibility of processes that produce visually appealing images with those that perform target detection is illustrated. C1 USN, Ctr Surface Warfare, Signal & Image Proc Branch, Dahlgren Div,Coastal Syst Stn, Panama City, FL 32407 USA. RP Smith, CM (reprint author), USN, Ctr Surface Warfare, Signal & Image Proc Branch, Dahlgren Div,Coastal Syst Stn, Code R12, Panama City, FL 32407 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2841-8 J9 PROC SPIE PY 1998 VL 3392 BP 1188 EP 1196 PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL85T UT WOS:000076961000115 ER PT S AU Cooper, MT Rankin, W Lathrop, J Castelin, S Nelson, H AF Cooper, MT Rankin, W Lathrop, J Castelin, S Nelson, H BE Dubey, AC Harvey, JF Broach, JT TI Ship organic mine countermeasures (MCM) for unencumbered maneuver from the sea SO DETECTION AND REMEDIATION TECHNOLOGIES FOR MINES AND MINELIKE TARGETS III, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Detection and Remediation Technologies for Mines and Minelike Targets III CY APR 13-17, 1998 CL ORLANDO, FL SP SPIE DE mines; sonars; electro-optics; magnetic; countermeasures; lasers; remotely operated vehicles; helicopters AB Mines present a severe and ongoing threat to operations of the Navy. They are available to any potential adversary. Dedicated mine countermeasures assets are not likely to be available in sufficient numbers to effectively counter the threat. Several systems can be mounted organically in surface combatant units. They include onboard systems and Remotely Operated Vehicles carrying Advanced Sensors capable of seamless mine detection in all waters. No one system can perform the entire mission, and a mix of appropriate systems will be required. This paper will describe the nature of the mine threat. It will discuss various available systems that can be used organically with the Fleet, the considerations that were operative in the design of each system, and the special role that each system can play given its peculiar characteristics. It is stressed that the Navy will be forced to deal with mines for the indefinite future, and that solutions can be and have been found for this problem. C1 USN, Ctr Surface Warfare, Dahlgren Div, Coastal Syst Stn, Washington, DC 20350 USA. RP Cooper, MT (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Coastal Syst Stn, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2841-8 J9 PROC SPIE PY 1998 VL 3392 BP 1249 EP 1260 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL85T UT WOS:000076961000121 ER PT B AU Mechtel, DM AF Mechtel, DM BE Brown, WD Ang, SS Loboda, M Sammakia, B Singh, R Rathore, HS TI Poled organic dielectrics for multilayer testability SO DIELECTRIC MATERIAL INTEGRATION FOR MICROELECTRONICS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd International Symp on Low and High Dielectric Constant Materials - Materials Science, Processing, and Reliability Issues at the 193rd Electrochemical-Society Meeting CY MAY 03-08, 1998 CL SAN DIEGO, CA SP Electrochem Soc, Dielectr Sci & Technol Div AB Poled organic dielectric layers offer promise as agents for the noninvasive testing of multichip modules (MCMs) using electro-optic techniques. MCM structures were fabricated with poled polyimide interlayer dielectrics and thin film metallizations on silicon carriers. a laser-based instrument was used to measure the on-substrate strength of electric fields emanating from circuit elements typical of those found in MCMs. The physical properties of these doped and poled dielectric layers are reported. The effect of variations in the poling and processing operations on these properties is also discussed. C1 USN Acad, Annapolis, MD 21401 USA. RP Mechtel, DM (reprint author), USN Acad, 105 Maryland Ave, Annapolis, MD 21401 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-197-8 J9 ELEC SOC S PY 1998 VL 98 IS 3 BP 279 EP 287 PG 9 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Characterization & Testing SC Electrochemistry; Engineering; Materials Science GA BL84L UT WOS:000076919500027 ER PT S AU Holland, OT Stiegler, RL AF Holland, OT Stiegler, RL BE Suresh, R TI Technology evaluation, assessment, modeling, and simulation: the TEAMS capability SO DIGITIZATION OF THE BATTLESPACE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Digitization of the Battlespace III CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE AB The United States Marine Corps' Technology Evaluation, Assessment, Modeling and Simulation (TEAMS) capability, located at the Naval Surface Warfare Center in Dahlgren Virginia, provides an environment for detailed test, evaluation, and assessment of live and simulated sensor and sensor-to-shooter systems for the joint warfare community. Frequent use of modeling and simulation allows for cost effective testing, bench-marking, and evaluation of various levels of sensors and sensor-to-shooter engagements. Interconnectivity to live, instrumented equipment operating in real battle space environments and to remote modeling and simulation facilities participating in advanced distributed simulations (ADS) exercises is available to support a wide-range of situational assessment requirements. TEAMS provides a valuable resource for a variety of users. Engineers, analysts, and other technology developers can use TEAMS to evaluate, assess and analyze tactical relevant phenomenological data on tactical situations. Expeditionary warfare and USMC concept developers can use the facility to support and execute advanced warfighting experiments (AWE) to better assess operational maneuver from the sea (OMFTS) concepts, doctrines, and technology developments. Developers can use the facility to support sensor system hardware, software and algorithm development as well as combat development, acquisition, and engineering processes. Test and evaluation specialists can use the facility to plan, assess, and augment their processes. This paper presents an overview of the TEAMS capability and focuses specifically on the technical challenges associated with the integration of live sensor hardware into a synthetic environment and how those challenges are being met. Existing sensors, recent experiments and facility specifications are featured. C1 USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Holland, OT (reprint author), USN, Ctr Surface Warfare, 17320 Dahlgren Rd,MS G305, Dahlgren, VA 22448 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2842-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3393 BP 54 EP 62 DI 10.1117/12.317672 PG 9 WC Optics; Telecommunications SC Optics; Telecommunications GA BL66Z UT WOS:000076266100007 ER PT B AU Marchette, DJ Priebe, CE AF Marchette, DJ Priebe, CE BE Weisberg, S TI Alternating kernel and mixture density estimates SO DIMENSION REDUCTION, COMPUTATIONAL COMPLEXITY AND INFORMATION SE COMPUTING SCIENCE AND STATISTICS (SERIES) LA English DT Proceedings Paper CT 30th Symposium on Interface Between Computing Science and Statistics CY MAY 13-16, 1998 CL MINNEAPOLIS, MN SP Nat Security Agcy, Univ Minnesota, Coll Liberal Arts, SAS Inst Inc AB We describe and investigate a data-driven procedure for obtaining parsimonious mixture model estimates or, conversely, kernel estimates with data-driven local smoothing properties. The main idea is to obtain a semiparametric estimate by alternating between the parametric and nonparametric viewpoints. C1 USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Marchette, DJ (reprint author), USN, Ctr Surface Warfare, Code B10, Dahlgren, VA 22448 USA. RI Priebe, Carey E./A-3305-2010 NR 15 TC 0 Z9 0 U1 0 U2 0 PU INTERFACE FOUNDATION NORTH AMERICA PI FAIRFAX PA PO BOX 7460, FAIRFAX, VA 22039-7460 USA BN 1-886658-05-6 J9 COMP SCI STAT PY 1998 VL 30 BP 116 EP 123 PG 8 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Statistics & Probability SC Computer Science; Mathematics GA BN90B UT WOS:000083408300021 ER PT B AU Solka, JL Wegman, EJ Reid, L Poston, WL AF Solka, JL Wegman, EJ Reid, L Poston, WL BE Weisberg, S TI Explorations of the space of orthogonal transformations from R-P to R-P using space-filling curves SO DIMENSION REDUCTION, COMPUTATIONAL COMPLEXITY AND INFORMATION SE COMPUTING SCIENCE AND STATISTICS (SERIES) LA English DT Proceedings Paper CT 30th Symposium on Interface Between Computing Science and Statistics CY MAY 13-16, 1998 CL MINNEAPOLIS, MN SP Nat Security Agcy, Univ Minnesota, Coll Liberal Arts, SAS Inst Inc AB This paper discusses our recent work in the utilization of space-filling curves for the exploration of the space of orthogonal transformations of a multivariate data set. We describe a new approach based on the use of a hyperspace-filling curve of the Peano type. A brief account of the mathematics of two-dimensional, three-dimensional, and hyper-dimensional Peano curves is provided along with some discussions on other methods of exploring the space of possible projections. Finally we illustrate how the hyper-dimensional Peano curve can be used to explore the above-mentioned space of linear orthographic projections. C1 USN, Ctr Surface Warfare, Dahlgren Div, Syst Res & Technol Dept, Dahlgren, VA 22448 USA. RP Solka, JL (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Syst Res & Technol Dept, Dahlgren, VA 22448 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU INTERFACE FOUNDATION NORTH AMERICA PI FAIRFAX PA PO BOX 7460, FAIRFAX, VA 22039-7460 USA BN 1-886658-05-6 J9 COMP SCI STAT PY 1998 VL 30 BP 494 EP 498 PG 5 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Statistics & Probability SC Computer Science; Mathematics GA BN90B UT WOS:000083408300089 ER PT B AU Hazen, GB Felli, JC AF Hazen, GB Felli, JC BE Weisberg, S TI Bayesian sensitivity analysis SO DIMENSION REDUCTION, COMPUTATIONAL COMPLEXITY AND INFORMATION SE COMPUTING SCIENCE AND STATISTICS (SERIES) LA English DT Proceedings Paper CT 30th Symposium on Interface Between Computing Science and Statistics CY MAY 13-16, 1998 CL MINNEAPOLIS, MN SP Nat Security Agcy, Univ Minnesota, Coll Liberal Arts, SAS Inst Inc C1 USN, Postgrad Sch, Monterey, CA 93940 USA. RP Hazen, GB (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INTERFACE FOUNDATION NORTH AMERICA PI FAIRFAX PA PO BOX 7460, FAIRFAX, VA 22039-7460 USA BN 1-886658-05-6 J9 COMP SCI STAT PY 1998 VL 30 BP 499 EP 499 PG 1 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Statistics & Probability SC Computer Science; Mathematics GA BN90B UT WOS:000083408300090 ER PT B AU Buttrey, SE AF Buttrey, SE BE Weisberg, S TI Discrimination with categorical variables SO DIMENSION REDUCTION, COMPUTATIONAL COMPLEXITY AND INFORMATION SE COMPUTING SCIENCE AND STATISTICS (SERIES) LA English DT Proceedings Paper CT 30th Symposium on Interface Between Computing Science and Statistics CY MAY 13-16, 1998 CL MINNEAPOLIS, MN SP Nat Security Agcy, Univ Minnesota, Coll Liberal Arts, SAS Inst Inc DE discrimination; classification; optimal scaling; categorical variables AB A new method for discrimination when all or most predictor variables are categorical is given. In this technique the class labels and categorical values are simultaneously mapped into red numbers so as to minimize a particular sum of squares. In the case of C classes it turns out that each class can be represented in a space whose dimension is at most C - 1. Observations can also be located in this space. This leads to a discrimination rule requiring the computation of at most C - 1 weighted Euclidean distances. For some well-known data sets, this technique produces accuracy competitive with any other classifier. C1 USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. RP Buttrey, SE (reprint author), USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU INTERFACE FOUNDATION NORTH AMERICA PI FAIRFAX PA PO BOX 7460, FAIRFAX, VA 22039-7460 USA BN 1-886658-05-6 J9 COMP SCI STAT PY 1998 VL 30 BP 550 EP 555 PG 6 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Statistics & Probability SC Computer Science; Mathematics GA BN90B UT WOS:000083408300098 ER PT J AU Doolan, DL Hedstrom, RC Gardner, MJ Sedegah, M Wang, H Gramzinski, RA Margalith, M Hobart, P Hoffman, SL AF Doolan, DL Hedstrom, RC Gardner, MJ Sedegah, M Wang, H Gramzinski, RA Margalith, M Hobart, P Hoffman, SL TI DNA vaccination as an approach to malaria control: Current status and strategies SO DNA VACCINATION / GENETIC VACCINATION SE CURRENT TOPICS IN MICROBIOLOGY AND IMMUNOLOGY LA English DT Review ID SPOROZOITE SURFACE PROTEIN-2; YOELII CIRCUMSPOROZOITE PROTEIN; T-CELLS RECOGNIZE; PLASMODIUM-YOELII; INFECTED HEPATOCYTES; MONOCLONAL-ANTIBODY; PROTECTIVE IMMUNITY; GENE-EXPRESSION; PLASMID DNA; IN-VIVO C1 USN, Med Res Inst, Malaria Program, Rockville, MD 20852 USA. Vical Inc, San Diego, CA 92121 USA. RP Doolan, DL (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. RI Doolan, Denise/F-1969-2015 NR 63 TC 28 Z9 28 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN 33 PA HEIDELBERGER PLATZ 3, W-1000 BERLIN 33, GERMANY SN 0070-217X J9 CURR TOP MICROBIOL JI Curr.Top.Microbiol.Immunol. PY 1998 VL 226 BP 37 EP 56 PG 20 WC Immunology; Microbiology SC Immunology; Microbiology GA BK22E UT WOS:000071570500003 PM 9479834 ER PT B AU Etoch, J AF Etoch, J GP AFS AFS AFS TI Ductile iron bomb body, a new application (abstract only) SO DUCTILE IRON SOCIETY'S 1998 KEITH D MILLIS WORLD SYMPOSIUM ON DUCTILE IRON LA English DT Meeting Abstract CT 1998 Keith D Millis World Symposium on Ductile Iron CY OCT 20-22, 1998 CL HILTON HEAD ISL, SC SP Ductile Iron Soc, Amer Foundrymens Soc C1 USN, Air Warfare Ctr, Weap Div, China Lake, CA 93555 USA. RP Etoch, J (reprint author), USN, Air Warfare Ctr, Weap Div, 1 Admin Circle, China Lake, CA 93555 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER FOUNDRYMENS SOC PI DES PLAINES PA GOLF AND WOLF RDS, DES PLAINES, IL 60016 USA PY 1998 BP 571 EP 572 PG 2 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA BR98E UT WOS:000168251500021 ER PT J AU Piacsek, S Allard, R Warn-Varnas, A AF Piacsek, S Allard, R Warn-Varnas, A TI Surface cooled convection simulations with application to ice-covered seas SO DYNAMICS OF ATMOSPHERES AND OCEANS LA English DT Article ID DEEP CONVECTION; NUMERICAL-MODEL; GREENLAND-SEA; LEADS; OCEAN AB Some idealized numerical experiments were carried out to study certain basic aspects of convective motions likely to occur during cooling and ice formation in the Nordic seas. The studies were restricted to two-dimensional motions in shallow water up to 300 m deep. The freezing point was not assumed to depend on salinity. Cooling rates of 200-500 W m(-2) (mass flux rates of (4-10) x 10(-5) kg m(-2) s(-1)), and brine discharge rates of (4-8) x 10(-5) kg m(-2) s(-1) were assumed, the latter corresponding roughly to a 1 cm h(-1) ice growth. The initial fluid state was assumed to be homogeneous, having been thoroughly stirred by the preceding strong wind events common to those regions. It was assumed that upon reaching the freezing temperature, all further cooling of the surface goes into ice formation, thus losing the buoyancy forcing owing to the cooling-associated mass flux. Under these conditions, the results showed that the occurrence of freezing regions and ice formation can either inhibit or enhance convection in the underlying water masses, depending on the ratio of the cooling-associated mass flux loss (owing to ice formation) to the brine release mass flux gain. Another important dependence was found on diffusivity, which can enhance (or diminish) the heat advected from the ambient ocean below, The augmentation of the upward heat flux by the higher diffusivity delayed both the onset of freezing and the growth of the freezing area, thus diminishing the loss of buoyancy forcing owing to the (higher) cooling-associated mass flux. For a cooling/brine mass flux ratio of five, the kinetic energy of the no-freezing system exceeded that of the freezing system by a factor of three. For cooling rates of 476 W m(-2) the maximum vertical velocities of the no-freeze simulation steadied at about 10 cm s(-1), and for the case of cooling-freezing with a mass flux ratio of about five, at about 5 cm s(-1). These values are within the range observed in penetrative ocean convection, or simulated by previous modelers in convection experiments. In the case of insufficient cooling (238 vs. 476 W m(-2)), the freezing point was reached only briefly, with brine injection lasting for a period of about 3 h. Then the heat transported from below by the convective cells (mainly driven by cooling-associated buoyancy) raised the surface temperature to above freezing conditions. (C) 1997 Elsevier Science B.V. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Piacsek, S (reprint author), USN, Res Lab, Code 7322, Stennis Space Ctr, MS 39529 USA. OI Allard, Richard/0000-0002-6066-2722 NR 18 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0265 J9 DYNAM ATMOS OCEANS JI Dyn. Atmos. Oceans PD JAN PY 1998 VL 27 IS 1-4 BP 601 EP 617 DI 10.1016/S0377-0265(97)00033-X PG 17 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography GA YV598 UT WOS:000071842700033 ER PT J AU Kristl, J Esplin, M Hudson, T Taylor, M Siefring, CL AF Kristl, J Esplin, M Hudson, T Taylor, M Siefring, CL TI Preliminary data on variations of OH airglow during the Leonid 1999 meteor storm SO EARTH MOON AND PLANETS LA English DT Article DE ablation; airglow; Leonids 1999; lower thermosphere; O-2; OH; mesosphere; meteor AB As part of the 1999 Leonid MAC Campaign an extensive set of infrared (1.00 - 1.65 mum) airglow spectra and imaging data were collected from onboard the USAF FISTA aircraft. These data will permit a detailed study of the upper atmospheric conditions over a several day period centered on the Leonid meteor storm of 17/18 November, 1999 as well as during the meteor storm itself. We describe initial results of a spectral analysis that indicates a small but significant enhancement in the OH airglow emission during the peak of the storm but we cannot yet be certain of a cause and effect relationship. No similar systematic enhancement was observed in the O-2 (1.27 mum) airglow emission recorded with the same instrument. C1 Utah State Univ Res Fdn, Space Dynam Lab, Logan, UT 84301 USA. USN, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. RP Kristl, J (reprint author), Utah State Univ Res Fdn, Space Dynam Lab, Logan, UT 84301 USA. EM jkristl@sdl.usu.edu NR 7 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 J9 EARTH MOON PLANETS JI Earth Moon Planets PY 1998 VL 82-3 BP 525 EP 534 DI 10.1023/A:1017016918056 PG 10 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 372TM UT WOS:000165250200037 ER PT S AU Duffy, ER AF Duffy, ER BE Rice, RC Tritsch, DE TI Effects of wear-resistant coatings on the fatigue strength of 4340 steel SO EFFECTS OF PRODUCT QUALITY AND DESIGN CRITERIA ON STRUCTURAL INTEGRITY SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Effects of Product Quality and Design on Structural Integrity CY MAY 05, 1997 CL ST LOUIS, MO SP ASTM Comm E8 Fatigue & Fracture DE chromium plating; electroless nickel; fatigue; tensile strength; shot peening; residual stress; sliding wear; 4340 steel AB For applications using 4340 steel where hardened surfaces;Ire required in a marine environment, surface coatings are necessary. Coatings that resist corrosion and provide wear resistance generally degrade the fatigue performance of the substrate metal. Shot peening before plating was ineffective in preventing a loss of fatigue life of plated steel bars compared to bare steel test bars which were not shot peened. The maximum residual compressive strength produced by shot peening was measured and was less than the maximum applied tensile stress in fatigue. As-plated electroless nickel has poor sliding wear resistance compared to either electroplated nickel or chromium in sliding wear at a contact stress of 37 Mpa. The tensile strength decreased in proportion to the volume fraction of coating applied to the steel substrate. C1 USN, Aviat Depot N Isl, San Diego, CA 92135 USA. RP Duffy, ER (reprint author), USN, Aviat Depot N Isl, Code 43410, San Diego, CA 92135 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2485-6 J9 AM SOC TEST MATER PY 1998 VL 1337 BP 133 EP 147 DI 10.1520/STP12346S PG 3 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM04B UT WOS:000077471300007 ER PT S AU Daly, GM Murata, H Merritt, CD Kafafi, ZH Inada, H Shirota, Y AF Daly, GM Murata, H Merritt, CD Kafafi, ZH Inada, H Shirota, Y BE Reynolds, JR Jen, AKY Rubner, MF Chiang, LY Dalton, LR TI Plastic multilayered molecular organic light emitting diodes SO ELECTRICAL, OPTICAL, AND MAGNETIC PROPERTIES OF ORGANIC SOLID-STATE MATERIALS IV SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Electrical, Optical, and Magnetic Properties of Organic Solid-State Materials IV CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Int Specialty Prod, Natl Taiwan Univ, Taiwan Four Pillars, Taiwan President Enterprises, United Microelectr Corp AB Enhanced performance has been observed for plastic molecular organic light emitting diodes (MOLEDs) consisting of two to four organic layers sequentially vacuum vapor deposited onto patterned indium-tin oxide (ITO) on polyester films. For all device structures studied, the performance of plastic diodes is comparable to or better than their analogs on glass substrates. At 100 A/m(2), a luminous power efficiency of 4.4 lm/W and external quantum yield of 2.7% are measured for a device structure consisting of two hole transport layers, a doped emitting layer and an electron transport layer on a polyester substrate. The same device made on a silica substrate has a luminous power efficiency of 3.5 lm/W and external quantum yield of 2.3%. Electrical and optical performance for comparable device structures has been characterized by current-voltage-luminance measurements and electroluminescence spectra collected normal to the emitting surface. In addition, an integrating sphere was used to collect the total light emitted and to determine the optical output coupling on glass versus plastic substrates. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kafafi, ZH (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Murata, Hideyuki/J-8453-2012 OI Murata, Hideyuki/0000-0001-8248-9652 NR 0 TC 4 Z9 4 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-393-2 J9 MATER RES SOC SYMP P PY 1998 VL 488 BP 33 EP 38 PG 4 WC Chemistry, Applied; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Chemistry; Engineering; Materials Science; Optics GA BL06U UT WOS:000074149700005 ER PT S AU Shaffer, RE Combs, RJ AF Shaffer, RE Combs, RJ BE Fallahi, M Howden, E TI Signal processing strategies for passive FT-IR sensors SO ELECTRO-OPTICAL TECHNOLOGY FOR REMOTE CHEMICAL DETECTION AND IDENTIFICATION III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Electro-Optical Technology for Remote Chemical Detection and Identification III CY APR 13, 1998 CL ORLANDO, FL SP SPIE DE chemometrics; multivariate calibration; pattern recognition; FT-IR; infrared analysis; interferogram; radiometric model; remote sensing; chemical detection AB Computer-generated synthetic single-beam spectra and interferograms are used to study signal processing strategies for passive Fourier transform infrared (FT-IR) sensors. Synthetic data are generated for one-, two-, and four-component mixtures of organic vapors in two passive FT-IR remote sensing scenarios. The single-beam spectra are processed using Savitsky-Golay smoothing, first derivative, and second derivative filters of various orders and widths. Interferogram data are processed by Fourier filtering using Gaussian-shaped bandpass digital filters. Pattern recognition of the target analyte spectral signature is performed using soft independent modeling of class analogy (SIMCA). Quantitative models for the target gas integrated concentration-path length product are built using partial least-squares (PLS) regression and locally weighted regression(LWR). Pattern recognition and calibration models of the filtered spectra and interferograms produced similar results. Chemical detection is possible for complex mixtures if the temperature difference between the source and analyte cloud is sufficiently large. Quantitative analysis is possible if the temperature of the analyte cloud is stable or known and is sufficiently different from the background temperature. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Shaffer, RE (reprint author), USN, Res Lab, Div Chem, Code 6116, Washington, DC 20375 USA. RI Shaffer, Ronald/I-2134-2012 NR 0 TC 5 Z9 5 U1 1 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2832-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3383 BP 92 EP 103 DI 10.1117/12.317639 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL67X UT WOS:000076298700009 ER PT J AU O'Grady, WE Ramaker, DE AF O'Grady, WE Ramaker, DE TI 'Atomic' X-ray absorption fine structure: a new tool for examining electrochemical interfaces SO ELECTROCHIMICA ACTA LA English DT Article DE in situ X-ray absorption spectroscopy; XAS; atomic XAFS; EXAFS; electrochemistry ID EXAFS AB Systematic changes in the magnitude of the atomic X-ray absorption fine structure AXAFS have been observed for the in situ charging of a Pt/C electrode in 0.1 M H2SO4. Using cluster calculations with0.0 and +/-0.05 electrons per surface Pt atom it has been possible to quantitatively calculate the changes observed in the AXAFS and explain the source of these changes from an electrochemical point of view. Published by Elsevier Science Ltd. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. George Washington Univ, Dept Chem, Washington, DC 20052 USA. RP O'Grady, WE (reprint author), USN, Res Lab, Div Chem, Code 6170, Washington, DC 20375 USA. NR 15 TC 18 Z9 19 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PY 1998 VL 44 IS 8-9 BP 1283 EP 1287 DI 10.1016/S0013-4686(98)00249-7 PG 5 WC Electrochemistry SC Electrochemistry GA 148XJ UT WOS:000077559300002 ER PT J AU Melendres, CA Mansour, AN AF Melendres, CA Mansour, AN TI X-ray absorption spectroelectrochemical cell for "in-situ" studies of thin films SO ELECTROCHIMICA ACTA LA English DT Article DE X-ray absorption spectroscopy; nickel oxide films; X-ray spectroelectrochemical cell; ultracapacitor material; electrodeposited films ID NICKEL AB A thin layer X-ray absorption spectroelectrochemical cell is described, It is suitable for "in-situ" studies of thin films and has the advantage that both fluorescence and transmission measurements can be made at the same time so as to ensure accurate calibration of the X-ray energy. Use of the cell is demonstrated in a study of the structure of a nickel oxide material anodically deposited on a graphite substrate which contains multivalent nickel states and appears promising for use in the fabrication of ultracapacitors. Published by Elsevier Science Ltd. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Naval Surface Warfare Ctr, Carderock Div, W Bethesda, MD 20817 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Melendres, CA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 TC 5 Z9 5 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PY 1998 VL 43 IS 5-6 BP 631 EP 634 PG 4 WC Electrochemistry SC Electrochemistry GA YM057 UT WOS:000071023600021 ER PT J AU Fontanella, JJ Wintersgill, MC Wainright, JS Savinell, RF Litt, M AF Fontanella, JJ Wintersgill, MC Wainright, JS Savinell, RF Litt, M TI High pressure electrical conductivity studies of acid doped polybenzimidazole SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 5th International Symposium on Polymer Electrolytes (ISPE-5) CY AUG 10-16, 1996 CL UPPSALA, SWEDEN DE polybenzimidazole; electrical conductivity; high pressure; activation volume ID WEIGHT NAFION MEMBRANES; POLYMER ELECTROLYTE; NMR AB Electrical conductivity studies of acid doped poplybenzimidazole (PBI) and 85% phosphoric acid have been carried out. The PBI contained about 600 mol% of 85% phosphoric acid and the electrical conductivity was deduced from complex impedance studies which were made at frequencies from 10 to 10(7) Hz. Measurements were made at pressures up to 0.25 GPa and temperatures of about 25, 50 and 75 degrees C. Similar measurements were also carried out on 85% phosphoric acid. At room temperature the electrical conductivity decreases with increasing pressure for both acid doped PBI and 85% phosphoric acid. This behavior is expected for normal liquids and for ions in polymers where the viscosity increases with pressure. The resultant positive activation volume for the acid doped PBI has a magnitude similar to that for polymer electrolytes based on perfluorosulfonic acid containing relatively small amounts of water. Further, as temperature increases, the activation volume becomes smaller. Consequently, the acid doped PBI behaves like a polymer electrolyte where ion transport is mediated by segmental motions of the polymer. Consequently, the acid doped PBI behaves like a polymer electrolyte where ion transport is mediated by segmental motions of the polymer. On the other hand, the activation volume at room temperature for 85% phosphoric acid is much smaller than for acid doped PBI. In addition, at 75 degrees C the electrical conductivity increases with increasing pressure which gives rise to a negative activation volume. Consequently, there is very little similarity between the electrical behavior of the 85% phosphoric acid and of the acid doped PBI which were studied in the present work. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Phys, Annapolis, MD 21402 USA. Case Western Reserve Univ, Dept Chem Engn, Ernest B Yeager Ctr Electrochem Sci, Cleveland, OH 44106 USA. Case Western Reserve Univ, Dept Macromol Sci & Engn, Cleveland, OH 44106 USA. RP Fontanella, JJ (reprint author), USN Acad, Dept Phys, Annapolis, MD 21402 USA. NR 21 TC 137 Z9 143 U1 2 U2 15 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PY 1998 VL 43 IS 10-11 BP 1289 EP 1294 DI 10.1016/S0013-4686(97)10032-9 PG 6 WC Electrochemistry SC Electrochemistry GA ZT361 UT WOS:000074077400023 ER PT J AU Edmondson, CA Stallworth, PE Wintersgill, MC Fontanella, JJ Dai, Y Greenbaum, SG AF Edmondson, CA Stallworth, PE Wintersgill, MC Fontanella, JJ Dai, Y Greenbaum, SG TI Electrical conductivity and NMR studies of methanol/water mixtures in Nafion membranes SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 5th International Symposium on Polymer Electrolytes (ISPE-5) CY AUG 10-16, 1996 CL UPPSALA, SWEDEN DE Nafion; electrical conductivity; deuteron NMR; methanol; activation volume; high pressure ID PERFLUOROSULFONATE IONOMER MEMBRANES; HIGH-PRESSURE NMR; DIELECTRIC-RELAXATION; AC-IMPEDANCE; TRANSPORT; DIFFUSION AB Complex impedance studies have been carried out in acid form Nafion 117 treated with various amounts of methanol and methanol-water mixtures. At room temperature and atmospheric pressure the conductivity for Nafion treated with "pure" methanol is about a factor of ten less than for Nafron which contains the same wt.% of water. In samples treated with the water-methanol mixtures, the conductivity is lower than for samples having the same total wt.% of water. However, for low mixed fluid wt.% the conductivity is significantly higher than for samples with the same amount of water, only, as was in the mix. This enhancement of conductivity over that for the corresponding water uptake is attributed to a plasticizing effect of the methanol facilitating the segmental motion of the polymer. At higher water concentrations, the conductivity is generally lower in the mixed solution-treated samples than in samples treated with the corresponding amount of water. This is to be expected since in this regime, proton conduction occurs in fluid-rich regions, which in the solution case includes a large fraction of methanol. For a 40 wt.% 1.4:1 molar ratio film, the studies were carried out at pressures up to 0.3 GPa. It is found that the electrical conductivity decreases with increasing pressure. Both the electrical conductivity and the activation volume are similar to the result for Nafion containing the same amount of water only. Deuteron NMR spin-lattice relaxation measurements of isotopically enriched methanol/water mixtures in Nafion 117 at elevated pressure demonstrate greater molecular-level interactions between methanol and Nafion than between water and Nafion. This is consistent with the plasticizing effect observed in the conductivity results. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Phys, Annapolis, MD 21402 USA. CUNY Hunter Coll, Dept Phys, New York, NY 10021 USA. RP Wintersgill, MC (reprint author), USN Acad, Dept Phys, Annapolis, MD 21402 USA. NR 21 TC 44 Z9 44 U1 2 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PY 1998 VL 43 IS 10-11 BP 1295 EP 1299 DI 10.1016/S0013-4686(97)10033-0 PG 5 WC Electrochemistry SC Electrochemistry GA ZT361 UT WOS:000074077400024 ER PT J AU Wintersgill, MC Fontanella, JJ AF Wintersgill, MC Fontanella, JJ TI Complex impedance measurements on Nafion SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 5th International Symposium on Polymer Electrolytes (ISPE-5) CY AUG 10-16, 1996 CL UPPSALA, SWEDEN DE Nafion; complex impedance; electrical conductivity; high pressure; activation volume; methanol ID PERFLUOROSULFONATE IONOMER MEMBRANES; PRESSURE ELECTRICAL-CONDUCTIVITY; DIELECTRIC-RELAXATION; CRYSTALLINE POLYMERS; WATER; TRANSPORT; NMR; DIFFUSION; BEHAVIOR AB The need to develop an electrolytic membrane for an efficient, environmentally sound fuel cell has led to intense interest in proton conducting polymers in general and Nafion in particular. While it does not appear very likely that Nafion itself will ultimately prove to be the best choice-of material, it may be considered as a prototype membrane material. Initial interest focused on Nafion's potential use in a hydrogen fuel cell, in which case its conductivity in the presence of water is important, and so extensive studies of the electrical properties of Nafion at various levels of humidity were carried out. Two distinct regimes were identified, one at lower water contents and the other at high water contents. The possible conduction mechanisms associated with these regimes will be discussed. In addition, studies carried out at high pressure yielded activation volumes which provide further clues as to the conduction mechanisms involved. More recently, interest in Nafion as a membrane: material in methanol fuel cells has prompted investigation of its electrical properties in the presence of methanol alone and of methanol/water mixtures. It is clear that not only is Nafion an excellent proton conductor but it also exhibits significant methanol transport. This represents a serious crossover problem for fuel cell applications and it is important to be able to characterize the mechanisms involved. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Phys, Annapolis, MD 21402 USA. RP Wintersgill, MC (reprint author), USN Acad, Dept Phys, Annapolis, MD 21402 USA. NR 28 TC 59 Z9 60 U1 1 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PY 1998 VL 43 IS 10-11 BP 1533 EP 1538 DI 10.1016/S0013-4686(97)10049-4 PG 6 WC Electrochemistry SC Electrochemistry GA ZT361 UT WOS:000074077400063 ER PT B AU Saunders, M Fox, AG AF Saunders, M Fox, AG BE Kirkland, A Brown, PD TI Progress towards the full quantification of zone-axis convergent beam electron diffraction (CBED) patterns SO ELECTRON LA English DT Proceedings Paper CT International Centennial Symposium on the Electron CY SEP 15-17, 1997 CL CHURCHILL COLL, CAMBRIDGE, ENGLAND SP Univ Cambridge, Japan Sci & Technol Corp, British Steel, Cambridge Univ Press, EPSRC, Hitachi Ltd, Inst Mat, Inst Phys, JEOL Ltd, Kawasaki Steel Corp, Konica Corp, Matsushita Res Inst, Med Res Council, National Power, NEC, Nippon Motorola Ltd, NKK, NTT, Philips Electron Opt, Pioneer Electr Corp, Rolls-Royce plc, Sci Museum HO CHURCHILL COLL ID LATTICE-PARAMETER AB Convergent beam electron diffraction is a powerful tool for the analysis of crystalline thin films. The highly detailed intensity variations in a convergent beam pattern (CBP) contain vast amounts of information about the symmetry, atomic and electronic arrangement of the crystal. Since its introduction by Kossel and Mollenstedt in 1938 steady progress has been made towards the ultimate goal of extracting all of that information from the pattern. Here we discuss how CBED has developed from a technique which relied on the symmetry or position of features in the pattern to one where direct intensity measurements can be compared to computer simulation. The zone-axis CBED pattern matching technique of Bird and Saunders (ZAPMATCH) will be discussed as an example of these new quantitative methods. C1 USN, Postgrad Sch, Ctr Mat Sci & Engn, Dept Engn Mech, Monterey, CA 93943 USA. RP Saunders, M (reprint author), USN, Postgrad Sch, Ctr Mat Sci & Engn, Dept Engn Mech, Monterey, CA 93943 USA. RI Saunders, Martin/B-3082-2011 OI Saunders, Martin/0000-0001-6873-7816 NR 14 TC 0 Z9 0 U1 0 U2 2 PU INST MATERIALS PI LONDON PA 1 CARLTON HOUSE TERRACE, LONDON SW1Y 5DB, ENGLAND BN 1-86125-051-7 PY 1998 BP 545 EP 551 PG 3 WC Chemistry, Multidisciplinary; Engineering, Electrical & Electronic; Multidisciplinary Sciences; Physics, Multidisciplinary SC Chemistry; Engineering; Science & Technology - Other Topics; Physics GA BN40U UT WOS:000081833500063 ER PT B AU Menon, ESK Fox, AG Spanos, G AF Menon, ESK Fox, AG Spanos, G BE Benavides, HAC Yacaman, MJ TI Carbon in retained austenite SO ELECTRON MICROSCOPY 1998, VOL 2: MATERIALS SCIENCE 1 LA English DT Proceedings Paper CT 14th International Congress on Electron Microscopy CY AUG 31-SEP 04, 1998 CL CANCUN, MEXICO SP Mexican Soc Microscopy, Consejo Nacl Ciencia & Tecnol, Inst Nacl Invest Nucl, Univ Autonoma Estado Mexico, Univ Veracruzana, Ctr Invest & Estudios Avanzados, Univ Nacl Autonoma Mexico, Ctr Invest Mat Avanzados, Inst Politecn Nacl, Univ Autonoma Nuevo Leon C1 USN, Postgrad Sch, Dept Mech Engn, Ctr Mat Sci, Monterey, CA 93943 USA. RP Menon, ESK (reprint author), USN, Postgrad Sch, Dept Mech Engn, Ctr Mat Sci, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND BN 0-7503-0565-7 PY 1998 BP 211 EP 212 PG 2 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Microscopy SC Materials Science; Microscopy GA BL87H UT WOS:000077019900104 ER PT B AU Saunders, M Menon, ESK Hashimoto, RY Fox, AG AF Saunders, M Menon, ESK Hashimoto, RY Fox, AG BE Benavides, HAC Yacaman, MJ TI Interface EELS analysis: Comparison of spatial difference and Multivariate Statistical Analysis (MSA) techniques SO ELECTRON MICROSCOPY 1998, VOL 2: MATERIALS SCIENCE 1 LA English DT Proceedings Paper CT 14th International Congress on Electron Microscopy CY AUG 31-SEP 04, 1998 CL CANCUN, MEXICO SP Mexican Soc Microscopy, Consejo Nacl Ciencia & Tecnol, Inst Nacl Invest Nucl, Univ Autonoma Estado Mexico, Univ Veracruzana, Ctr Invest & Estudios Avanzados, Univ Nacl Autonoma Mexico, Ctr Invest Mat Avanzados, Inst Politecn Nacl, Univ Autonoma Nuevo Leon C1 USN, Postgrad Sch, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. RP Saunders, M (reprint author), USN, Postgrad Sch, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. RI Saunders, Martin/B-3082-2011 OI Saunders, Martin/0000-0001-6873-7816 NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND BN 0-7503-0565-7 PY 1998 BP 571 EP 572 PG 2 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Microscopy SC Materials Science; Microscopy GA BL87H UT WOS:000077019900280 ER PT B AU Menon, ESK Saunders, M AF Menon, ESK Saunders, M BE Benavides, HAC Yacaman, MJ TI Elemental distributions in Au-metallized CVDD SO ELECTRON MICROSCOPY 1998, VOL 3: MATERIALS SCIENCE 2 LA English DT Proceedings Paper CT 14th International Congress on Electron Microscopy CY AUG 31-SEP 04, 1998 CL CANCUN, MEXICO SP Mexican Soc Microscopy, Consejo Nacl Ciencia & Tecnol, Inst Nacl Invest Nucl, Univ Autonoma Estado Mexico, Univ Veracruzana, Ctr Invest & Estudios Avanzados, Univ Nacl Autonoma Mexico, Ctr Invest Mat Avanzados, Inst Politecn Nacl, Univ Autonoma Nuevo Leon C1 USN, Postgrad Sch, Dept Mech Engn, Ctr Mat Sci, Monterey, CA 93943 USA. RP Menon, ESK (reprint author), USN, Postgrad Sch, Dept Mech Engn, Ctr Mat Sci, Monterey, CA 93943 USA. RI Saunders, Martin/B-3082-2011 OI Saunders, Martin/0000-0001-6873-7816 NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND BN 0-7503-0566-5 PY 1998 BP 461 EP 462 PG 2 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Biomaterials; Microscopy SC Chemistry; Materials Science; Microscopy GA BL87J UT WOS:000077020300223 ER PT B AU Saunders, M Menon, ESK Fox, AG AF Saunders, M Menon, ESK Fox, AG BE Benavides, HAC Yacaman, MJ TI Using statistical methods to identify and map interface reaction phases from EDS spectra SO ELECTRON MICROSCOPY 1998, VOL 3: MATERIALS SCIENCE 2 LA English DT Proceedings Paper CT 14th International Congress on Electron Microscopy CY AUG 31-SEP 04, 1998 CL CANCUN, MEXICO SP Mexican Soc Microscopy, Consejo Nacl Ciencia & Tecnol, Inst Nacl Invest Nucl, Univ Autonoma Estado Mexico, Univ Veracruzana, Ctr Invest & Estudios Avanzados, Univ Nacl Autonoma Mexico, Ctr Invest Mat Avanzados, Inst Politecn Nacl, Univ Autonoma Nuevo Leon C1 USN, Postgrad Sch, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. RP Saunders, M (reprint author), USN, Postgrad Sch, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. RI Saunders, Martin/B-3082-2011 OI Saunders, Martin/0000-0001-6873-7816 NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND BN 0-7503-0566-5 PY 1998 BP 597 EP 598 PG 2 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Biomaterials; Microscopy SC Chemistry; Materials Science; Microscopy GA BL87J UT WOS:000077020300288 ER PT B AU Saunders, M Menon, ESK Fox, AG AF Saunders, M Menon, ESK Fox, AG BE Benavides, HAC Yacaman, MJ TI Quantitative convergent beam electron diffraction (CBED) studies of metals and intermetallic alloys SO ELECTRON MICROSCOPY 1998, VOL 3: MATERIALS SCIENCE 2 LA English DT Proceedings Paper CT 14th International Congress on Electron Microscopy CY AUG 31-SEP 04, 1998 CL CANCUN, MEXICO SP Mexican Soc Microscopy, Consejo Nacl Ciencia & Tecnol, Inst Nacl Invest Nucl, Univ Autonoma Estado Mexico, Univ Veracruzana, Ctr Invest & Estudios Avanzados, Univ Nacl Autonoma Mexico, Ctr Invest Mat Avanzados, Inst Politecn Nacl, Univ Autonoma Nuevo Leon C1 USN, Postgrad Sch, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. RP Saunders, M (reprint author), USN, Postgrad Sch, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. RI Saunders, Martin/B-3082-2011 OI Saunders, Martin/0000-0001-6873-7816 NR 0 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND BN 0-7503-0566-5 PY 1998 BP 779 EP 780 PG 2 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Biomaterials; Microscopy SC Chemistry; Materials Science; Microscopy GA BL87J UT WOS:000077020300375 ER PT B AU Rajagopal, AK AF Rajagopal, AK BE Dobson, JF Vignale, G Das, MP TI Effective action in density functional theory and the berry phase SO ELECTRONIC DENSITY FUNCTIONAL THEORY: RECENT PROGRESS AND NEW DIRECTIONS LA English DT Proceedings Paper CT International Workshop on Electronic Density Functional Theory - Recent Progress and New Directions CY JUL 14-19, 1996 CL NATHAN, AUSTRALIA C1 USN, Res Lab, Washington, DC 20375 USA. RP Rajagopal, AK (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-45834-9 PY 1998 BP 217 EP 225 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Atomic, Molecular & Chemical; Physics, Particles & Fields SC Chemistry; Materials Science; Physics GA BL05M UT WOS:000074127200015 ER PT B AU Rajagopal, AK AF Rajagopal, AK BE Dobson, JF Vignale, G Das, MP TI A functional theory of interacting local spins, spin polarized electrons, and ions: Half metallic magnets SO ELECTRONIC DENSITY FUNCTIONAL THEORY: RECENT PROGRESS AND NEW DIRECTIONS LA English DT Proceedings Paper CT International Workshop on Electronic Density Functional Theory - Recent Progress and New Directions CY JUL 14-19, 1996 CL NATHAN, AUSTRALIA C1 USN, Res Lab, Washington, DC 20375 USA. RP Rajagopal, AK (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-45834-9 PY 1998 BP 361 EP 371 PG 11 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Atomic, Molecular & Chemical; Physics, Particles & Fields SC Chemistry; Materials Science; Physics GA BL05M UT WOS:000074127200025 ER PT J AU Olson, PE Benenson, AS Genovese, EN AF Olson, PE Benenson, AS Genovese, EN TI Ebola/Athens revisited SO EMERGING INFECTIOUS DISEASES LA English DT Letter C1 USN, Balboa Hosp, San Diego, CA 92152 USA. San Diego State Univ, San Diego, CA 92182 USA. RP Olson, PE (reprint author), USN, Balboa Hosp, San Diego, CA 92152 USA. NR 0 TC 2 Z9 3 U1 1 U2 1 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD JAN-MAR PY 1998 VL 4 IS 1 BP 134 EP 134 PG 1 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA YX165 UT WOS:000072012900027 PM 9452412 ER PT J AU Chen, LG Wu, C Sun, FR AF Chen, LG Wu, C Sun, FR TI Influence of internal heat leak on the performance of refrigerators SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE performance characteristics; analysis refrigerator; heat leak; irreversibility ID COOLING LOAD; CYCLES; POWER; ENGINE; PLANTS AB The influence of an internal heat leak on the optimal performance of a refrigerator is examined in this paper. This is done by adding a heat leak term into an endoreversible refrigerator. The relation between optimal heating load and coefficients of performance (COP) for a steady-state irreversible refrigerator is derived. The performance characteristics of the irreversible refrigerator are found to be deeply affected by the rate of heat leak. This model allows a more reasonable prediction of the performance of an actual refrigerator. Published by Elsevier Science Ltd. C1 USN ACAD,DEPT ENGN MECH,ANNAPOLIS,MD 21402. RP Chen, LG (reprint author), NAVAL ACAD ENGN,FAC 306,WUHAN 430033,PEOPLES R CHINA. NR 23 TC 21 Z9 24 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0196-8904 J9 ENERG CONVERS MANAGE JI Energy Conv. Manag. PD JAN PY 1998 VL 39 IS 1-2 BP 45 EP 50 DI 10.1016/S0196-8904(96)00179-3 PG 6 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA YG398 UT WOS:A1998YG39800005 ER PT J AU Chen, LG Wu, C Sun, FR AF Chen, LG Wu, C Sun, FR TI Optimization of specific rate of heat pumping in combined heat pump cycles SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE heat pump; combined cycle; specific load; optimization ID REFRIGERATION PLANTS; POWER; PERFORMANCE AB The optimization problem of a combined heat pump cycle made of two endoreversible Carnot heat pump cycles in series without intermediate reservoirs is investigated using finite-time thermodynamics. The fundamental relation between heating quantity and coefficient of performance (COP) of the combined cycle is derived. Relations are also derived between the SRHP (specific rate of heat pumping), the average rate of heat pumping per unit of total heat-transfer surface area and the COP for reciprocating and stable flow models of combined cycles. The results obtained from this paper may be extended to an endoreversible, combined heat pump cycle formed by more than two endoreversible Carnot heat pump cycles. Published by Elsevier Science Ltd. C1 USN ACAD,DEPT ENGN MECH,ANNAPOLIS,MD 21402. RP Chen, LG (reprint author), NAVAL ACAD ENGN,FAC 306,WUHAN 430033,PEOPLES R CHINA. NR 28 TC 21 Z9 22 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0196-8904 J9 ENERG CONVERS MANAGE JI Energy Conv. Manag. PD JAN PY 1998 VL 39 IS 1-2 BP 113 EP 116 DI 10.1016/S0196-8904(96)00178-1 PG 4 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA YG398 UT WOS:A1998YG39800012 ER PT J AU Chen, LG Wu, C Sun, FR AF Chen, LG Wu, C Sun, FR TI Cooling load versus COP characteristics for an irreversible air refrigeration cycle SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE performance characteristics; Brayton cycle; refrigeration ID FINITE-TIME; CENTRIFUGAL CHILLERS; HEAT; PLANTS; POWER; MODEL AB The effect of heat resistance on the performance of an air refrigeration cycle is analyzed with a finite time heat transfer analysis. The present work extends the recent studies on refrigerator performance by incorporating nonisentropic compression and expansion. Relations between cooling load and pressure ratio and between COP (coefficient of performance) and pressure ratio for the air refrigeration cycle in which the irreversibilities of heat resistance losses in the hot and cold-side; heat exchangers and nonisentropic losses in the compression and expansion processes are derived. The results show that there exists a maximum value of COP and that the cooling load has a parabolic dependence on COP, unlike the monotonically decreasing behaviour in the case of an endoreversible air refrigeration cycle. Published by Elsevier Science Ltd. C1 NAVAL ACAD ENGN,FAC 306,WUHAN 430033,PEOPLES R CHINA. USN ACAD,DEPT ENGN MECH,ANNAPOLIS,MD 21402. NR 23 TC 58 Z9 66 U1 2 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0196-8904 J9 ENERG CONVERS MANAGE JI Energy Conv. Manag. PD JAN PY 1998 VL 39 IS 1-2 BP 117 EP 125 DI 10.1016/S0196-8904(96)00119-7 PG 9 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA YG398 UT WOS:A1998YG39800013 ER PT J AU Wu, C Chen, LG Sun, FR Cao, S AF Wu, C Chen, LG Sun, FR Cao, S TI Optimal collector temperature for solar-driven heat pumps SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE solar heat pump; collector temperature; optimization AB The optimal performance of an endoreversible solar-driven heat pump system consisting of a solar collector and a three-heat-reservoir heat pump is investigated. Two heat transfer models between the working fluid and the reservoirs of the heat pump are used in the system analysis. The overall coefficient of performance (COP) and heating load of the system are adopted to be the objective functions of the analysis. The analytical results found in the paper provide a basis for designing a real solar-driven heat pump system. Published by Elsevier Science Ltd. C1 NAVAL ACAD ENGN,FAC 306,WUHAN 430033,PEOPLES R CHINA. RP Wu, C (reprint author), USN ACAD,DEPT ENGN MECH,ANNAPOLIS,MD 21402, USA. NR 6 TC 9 Z9 10 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0196-8904 J9 ENERG CONVERS MANAGE JI Energy Conv. Manag. PD JAN PY 1998 VL 39 IS 1-2 BP 143 EP 147 DI 10.1016/S0196-8904(96)00121-5 PG 5 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA YG398 UT WOS:A1998YG39800015 ER PT J AU Pande, SG Hardy, DR AF Pande, SG Hardy, DR TI Effects of extended duration testing and time of addition of N,N '-disalicylidene-1,2-propanediamine on jet fuel thermal stability as determined using the gravimetric JFTOT SO ENERGY & FUELS LA English DT Article AB Two studies were conducted on the effects of the metal deactivator, N,N'-disalicylidene-1,2-propanediamine (MDA) on jet fuel thermal stability. Study 1 focused on the effects of MDA on extended duration thermal stability testings ranging from 120 to 152 h. The test fuel was a Jet A, and the effects of MDA were examined with and without the addition of the antioxidant, BHT (2,6-di-tert-butyl-4-methylphenol) as well as with and without added copper. For study 2, the thermal stability test duration was 2.5 h, and the effect of time of addition of MDA, which was also investigated in study 1, was further examined in a test matrix that comprised two JP-5 fuels, two sources of copper, and three concentrations of MDA. Thermal stability was determined using the gravimetric JFTOT. The results of the extended duration testings indicate that even at the relatively high MDA concentrations examined (15 and 35 ppm), MDA exhibited a beneficial effect in the non copper doped commercial (Jet A) and Navy type fuel (Jet A + BHT). The results of the time of MDA addition studies indicate that early addition of MDA is more effective than late addition, for copper-contaminated stored jet fuels. C1 Geocenters Inc, Lanham, MD 20706 USA. USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. RP Pande, SG (reprint author), Geocenters Inc, Lanham, MD 20706 USA. NR 25 TC 5 Z9 5 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD JAN-FEB PY 1998 VL 12 IS 1 BP 129 EP 138 DI 10.1021/ef970096r PG 10 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA YR751 UT WOS:000071526600018 ER PT B AU Moniz, DL AF Moniz, DL GP IEEE IEEE TI Developing practical, object-oriented middleware interfaces for data-intensive applications SO ENTERPRISE DISTRIBUTED OBJECT COMPUTING - PROCEEDINGS SECOND INTERNATIONAL WORKSHOP LA English DT Proceedings Paper CT 2nd International Enterprise Distributed Object Computing Workshop (EDOC98) CY NOV 02-05, 1998 CL LA JOLLA, CA SP IEEE, Object Management Grp (OMG), EIC, IPS, Distributed Syst Technol Ctr, UNISYS, FUJITSU AB Data-intensive applications require frequent interaction with shared data sources. The Common Object Request Broker Architecture (CORBA), an object-oriented middleware standard, provides facilities for the development of distributed interface objects. However, until recently, CORBA has had no provision for the definition of true data objects that can be transported to a client application, which has implications for application performance. This paper presents the issues surrounding the development of object-oriented CORBA interfaces for data-intensive applications. Also, two abstractions, aggregation and iteration, are presented for developing interface objects that can accommodate data-intensive applications using existing CORBA capabilities. C1 USN, Undersea Warfare Ctr Div Newport, Newport, RI 02841 USA. RP Moniz, DL (reprint author), USN, Undersea Warfare Ctr Div Newport, Code 2233,Bldg 1171-2, Newport, RI 02841 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5158-4 PY 1998 BP 174 EP 182 DI 10.1109/EDOC.1998.723253 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BM29G UT WOS:000078293900017 ER PT J AU Hyams, KC AF Hyams, KC TI Developing case definitions for symptom-based conditions: the problem of specificity SO EPIDEMIOLOGIC REVIEWS LA English DT Review ID CHRONIC-FATIGUE-SYNDROME; SICK-BUILDING SYNDROME; MULTIPLE CHEMICAL-SENSITIVITY; WORKING CASE-DEFINITION; CHRONIC POSTVIRAL FATIGUE; GULF-WAR VETERANS; FIBROMYALGIA SYNDROME; PRIMARY-CARE; ENVIRONMENTAL ILLNESS; BREAST IMPLANTS C1 USN, Med Res Inst, Div Epidemiol, Bethesda, MD USA. RP Hyams, KC (reprint author), USN, Med Res Ctr, 12300 Washington Ave, Rockville, MD 20852 USA. NR 124 TC 51 Z9 51 U1 0 U2 0 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 USA SN 0193-936X J9 EPIDEMIOL REV JI Epidemiol. Rev. PY 1998 VL 20 IS 2 BP 148 EP 156 PG 9 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 157UB UT WOS:000078079100002 PM 9919435 ER PT S AU Jernigan, GG Silvestre, CL Fatemi, M Twigg, ME Thompson, PE AF Jernigan, GG Silvestre, CL Fatemi, M Twigg, ME Thompson, PE BE Fitzgerald, EA Houghton, DC Mooney, PM TI Limitations to the use of Sb as a surfactant during SiGe MBE SO EPITAXY AND APPLICATIONS OF SI-BASED HETEROSTRUCTURES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Materials-Research-Society Symposium on Epitaxy and Applications of Si-Based Heterostructures CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc AB The use of Sb as a surfactant in suppressing Ge segregation during SiGe alloy growth was investigated as a function of Sb surface coverage, Ge alloy concentration, and alloy thickness using xray photoelectron spectroscopy, x-ray diffraction, and transmission electron microscopy. Unlike previous studies where Sb was found to completely quench Ge segregation into a Si capping layer, we find that Sb can not completely prevent Ge segregation while Si and Ge are being co-deposited. This results in the production of a non-square quantum well with missing Ge at the beginning and extra Ge at the end of the alloy. We also found that Sb does not relieve strain in thin films but does result in compositional or strain variations within thick alloy layers. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Jernigan, GG (reprint author), USN, Res Lab, Div Elect Sci & Technol, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-439-4 J9 MATER RES SOC SYMP P PY 1998 VL 533 BP 289 EP 294 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BL94L UT WOS:000077251100040 ER PT S AU Thompson, PE Silvestre, C Twigg, M Jernigan, G Simons, DS AF Thompson, PE Silvestre, C Twigg, M Jernigan, G Simons, DS BE Fitzgerald, EA Houghton, DC Mooney, PM TI The formation of abrupt N+ doping profiles using atomic hydrogen and Sb during Si MBE SO EPITAXY AND APPLICATIONS OF SI-BASED HETEROSTRUCTURES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Materials-Research-Society Symposium on Epitaxy and Applications of Si-Based Heterostructures CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc AB Previously, atomic hydrogen has been shown to be effective in reducing the segregation of Sb on Si(100) during solid source molecular beam epitaxy growth. In this work we have investigated the electrical activation of the Sb. Using Hall measurements, spreading resistance profilometry, and secondary ion mass spectrometry, we have demonstrated that the co-deposition of atomic hydrogen during Sb doping of Si at 500 degrees C produced well-defined doping spikes. Comparing the sheet carrier concentration obtained by Hall measurements to the Sb atomic concentration obtained by SIMS, the overall activation of the Sb was greater than 50%. C1 USN, Res Lab, Washington, DC 20375 USA. RP Thompson, PE (reprint author), USN, Res Lab, Code 6812, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-439-4 J9 MATER RES SOC SYMP P PY 1998 VL 533 BP 367 EP 372 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BL94L UT WOS:000077251100053 ER PT B AU Chu, PC Fan, CW AF Chu, PC Fan, CW BE Spaulding, ML Blumberg, AF TI Improvement of estuarine and coastal modeling using high-order difference schemes SO ESTUARINE AND COASTAL MODELING LA English DT Proceedings Paper CT 5th International Conference on Estuarine and Coastal Modeling CY OCT 22-24, 1997 CL ALEXANDRIA, VA ID COORDINATE OCEAN MODELS; SIGMA AB How to reduce the computational error is a key issue of using sigma-coordinate coastal ocean models. Due to the Fact that the higher the order of the difference scheme, the less the truncation error and the more complicated the computation, we introduce three sixth-order difference schemes (ordinary, compact, and combined compact) for the sigma-coordinate coastal models in order to reduce error without increasing much complexity of the computation. After the analytical error estimation, the Semi-Spectral Primitive Equation Model (SPEM) is used to demonstrate the benefit of using these schemes and to compare the difference among the three six-order schemes. Over a nide range of parameter space as well as a great parametric domain of numerical stability, the ordinary sixth-order scheme is shown to have error reductions by factors of 50 comparing to the second-order difference scheme. Among the sixth-order schemes, the compact scheme reduces error by more than 50-55% comparing to the ordinary scheme, and the combined compact scheme reduces error by more than 60% comparing to the compact scheme. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Chu, PC (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0350-3 PY 1998 BP 28 EP 34 PG 7 WC Engineering, Marine; Environmental Sciences; Geosciences, Multidisciplinary; Mathematics, Applied; Water Resources SC Engineering; Environmental Sciences & Ecology; Geology; Mathematics; Water Resources GA BP58L UT WOS:000085572100003 ER PT B AU Blain, CA AF Blain, CA BE Spaulding, ML Blumberg, AF TI Barotropic tidal and residual circulation in the Arabian Gulf SO ESTUARINE AND COASTAL MODELING LA English DT Proceedings Paper CT 5th International Conference on Estuarine and Coastal Modeling CY OCT 22-24, 1997 CL ALEXANDRIA, VA ID MODELING TIDES AB The tidal response in the Arabian Gulf is a mixed semi-diurnal and diurnal signal controlled through the Strait of Hormuz. Tidal elevations range between 0.5 - 1.5 m and tidal velocities are on the order of 0.2 - 0.5 m/s. The tidal residual circulation is most prevalent over a gradually sloping bottom in depths less than 15 - 20 m (i.e. off the U.A.E coast, in the northern Gulf, and near the cape at Ras-e Jabrin in Iraq). Numerous islands dotting the eastern Gulf and ragged coastlines through the Strait induce residual currents having magnitudes nearly 10% of the semi-diurnal and 25% of the diurnal frequencies present. Generally, Coriolis forcing acts as a constraint on generated residuals, reducing their magnitudes and confining residual circulation to follow along topographic gradients. At the sea bed a decrease in the frictional force enhances the tidal residuals. Despite the role of these nonlinear processes, advection remains the primary mechanism for the generation of residual currents. C1 USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. RP Blain, CA (reprint author), USN, Res Lab, Div Oceanog, Code 73622, Stennis Space Ctr, MS 39529 USA. NR 17 TC 5 Z9 5 U1 0 U2 1 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0350-3 PY 1998 BP 166 EP 180 PG 15 WC Engineering, Marine; Environmental Sciences; Geosciences, Multidisciplinary; Mathematics, Applied; Water Resources SC Engineering; Environmental Sciences & Ecology; Geology; Mathematics; Water Resources GA BP58L UT WOS:000085572100013 ER PT B AU Keen, TR Glenn, SM AF Keen, TR Glenn, SM BE Spaulding, ML Blumberg, AF TI Resuspension and advection of sediment during Hurricane Andrew on the Louisiana continental shelf SO ESTUARINE AND COASTAL MODELING LA English DT Proceedings Paper CT 5th International Conference on Estuarine and Coastal Modeling CY OCT 22-24, 1997 CL ALEXANDRIA, VA ID BOUNDARY-LAYER MODEL; COMBINED WAVE; MOVABLE BED; BOTTOM; FLOW; STORM AB Validated hindcast storm currents and waves are used to drive a coupled bottom boundary layer-sediment transport model for Hurricane Andrew. Shear stresses and suspended sediment profiles are computed using a combined wave-current bottom boundary layer model with variable bottom roughness. The sedimentation model calculates suspended sediment profiles, and suspended and bed load transport rates. Sediment erosion and deposition is found using mass conservation equations with advection and diffusion terms. The average model-predicted combined resuspension-advection sediment thickness during a 1-hour interval at the storm peak is less than 0.04 m, with a maximum of more than 2.6 m. C1 USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. RP Keen, TR (reprint author), USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. NR 15 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0350-3 PY 1998 BP 481 EP 494 PG 14 WC Engineering, Marine; Environmental Sciences; Geosciences, Multidisciplinary; Mathematics, Applied; Water Resources SC Engineering; Environmental Sciences & Ecology; Geology; Mathematics; Water Resources GA BP58L UT WOS:000085572100034 ER PT J AU Reibel, S Nadi, S Le, BT Larmet, Y Carnahan, J Marescaux, C Depaulis, A AF Reibel, S Nadi, S Le, BT Larmet, Y Carnahan, J Marescaux, C Depaulis, A TI Inhibitory effects of neuropeptide Y on epileptiform activity in vivo and in vitro SO EUROPEAN JOURNAL OF NEUROSCIENCE LA English DT Meeting Abstract C1 INSERM, U398, Strasbourg, France. USN, Med Res Inst, Bethesda, MD USA. UMR 7519, Strasbourg, France. AMGEN, Thousand Oaks, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0953-816X J9 EUR J NEUROSCI JI Eur. J. Neurosci. PY 1998 VL 10 SU 10 MA 2038 BP 48 EP 48 PG 1 WC Neurosciences SC Neurosciences & Neurology GA ZZ630 UT WOS:000074749400278 ER PT S AU Vohra, ST Althouse, B Johnson, G Vurpillot, S Inaudi, D AF Vohra, ST Althouse, B Johnson, G Vurpillot, S Inaudi, D BE Culshaw, B Jones, JDC TI Quasi-static strain monitoring during the 'push' phase of a box-girder bridge using fiber Bragg grating sensors SO EUROPEAN WORKSHOP ON OPTICAL FIBRE SENSORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT European Workshop on Optical Fibre Sensors CY JUL 08-10, 1998 CL PEEBLES, SCOTLAND SP Univ Strathclyde, Heriot Watt Univ, USAF, European Off Aerosp Res & Dev, European Comm Brite EuRam Programme, IEE, Inst Phys, Inst Measurement & Control, SPIE, IEEE, LEOS C1 USN, Res Lab, Washington, DC 20375 USA. RP Vohra, ST (reprint author), USN, Res Lab, Code 5670, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2938-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3483 BP 205 EP 208 DI 10.1117/12.309674 PG 4 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BL34V UT WOS:000075218900045 ER PT S AU Patrick, HJ Vohra, ST AF Patrick, HJ Vohra, ST BE Culshaw, B Jones, JDC TI Fiber Bragg grating with long period fiber grating superstructure for simultaneous strain and temperature measurement SO EUROPEAN WORKSHOP ON OPTICAL FIBRE SENSORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT European Workshop on Optical Fibre Sensors CY JUL 08-10, 1998 CL PEEBLES, SCOTLAND SP Univ Strathclyde, Heriot Watt Univ, USAF, European Off Aerosp Res & Dev, European Comm Brite EuRam Programme, IEE, Inst Phys, Inst Measurement & Control, SPIE, IEEE, LEOS C1 USN, Res Lab, Washington, DC 20375 USA. RP Patrick, HJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 3 Z9 3 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2938-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3483 BP 264 EP 267 DI 10.1117/12.309687 PG 4 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BL34V UT WOS:000075218900057 ER PT S AU Golembiewski, CM Cruddace, RG Kowalski, MP AF Golembiewski, CM Cruddace, RG Kowalski, MP BE Siegmund, OHW Gummin, MA TI Collimator design for the J-PEX sounding rocket SO EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY IX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy IX CY JUL 22-24, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers AB The Joint Astrophysical Plasmadynamic Experiment (J-PEX) is a high-resolution extreme ultraviolet spectrometer which operates at near-normal incidence and incorporates the most recent developments in reflecting multilayer gratings. The spectrometer comprises the following principal elements: collimators which define the 1.2 degrees field of view (FWHM), a spherical multilayer-coated grating which consists of 4 segments, each 8 cm x 16 cm in area and with a focal length of 2.2 m, and a microchannel plate imaging detector. The collimator is an adaptation of a previous design which was modified to minimize the input of scattered airglow radiation while maintaining the maximum effective area within the desired field of view. This is achieved by blackening the collimator surfaces with an EBONOL-C process. In this paper we will discuss the design requirements and manufacturing techniques for the collimator. C1 USN, Res Lab, Div Space Sci, Washington, DC 20375 USA. RP Golembiewski, CM (reprint author), USN, Res Lab, Div Space Sci, Code 7621, Washington, DC 20375 USA. NR 0 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2900-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3445 BP 197 EP 204 DI 10.1117/12.330277 PG 8 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BM19Y UT WOS:000078010600018 ER PT S AU Maraviglia, C Williams, E Pezzulich, A AF Maraviglia, C Williams, E Pezzulich, A BE Selander, JM TI Real time imaging systems' combination of methods to achieve automatic target recognition SO EXPLOITING NEW IMAGE SOURCES AND SENSORS, 26TH AIPR WORKSHOP SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 26th AIPR Workshop on Exploiting New Image Sources and Sensors CY OCT 15-17, 1997 CL WASHINGTON, D.C. SP Soc Photo Opt Instrumentat Engineers, Appl Imagery Pattern Recognit Execut Comm DE real time; ATR; ATR algorithms; history; missile; multi-sensor; imaging technology AB Using a combination of strategies real time imaging weapons systems are achieving their goals of detecting their intended targets. The demands of acquiring a target in a cluttered environment in a timely manner with a high degree of confidence demands compromises be made as to having a truly automatic system. A combination of techniques such as dedicated image processing hardware, real time operating systems, mixes of algorithmic methods, and multi-sensor detectors are a forbearance of the unleashed potential of future weapons systems and their incorporation in truly autonomous target acquisition. Elements such as position information, sensor gain controls, way marks for mid course:correction, and augmentation with different imaging spectrums as well as future capabilities such as neural net expert systems and decision processors over seeing a fusion matrix architecture may be considered tools for a weapon system's achievement of it's ultimate goal. Currently, acquiring a target in a cluttered environment in a timely manner with a high degree of confidence demands compromises be made as to having a truly automatic system. It is now necessary to include a human in the track decision loop, a system feature that may be long lived. Automatic Track Recognition will still be the desired goal in future systems due to the variability of military missions and desirability of an expendable asset. Furthermore, with the increasing incorporation of multi-sensor information into the track decision the human element's real time contribution must be carefully engineered. C1 USN, Res Lab, Adv Techniques Branch, Washington, DC 20350 USA. RP Maraviglia, C (reprint author), USN, Res Lab, Adv Techniques Branch, Code 5752,4555 Overlook Ave SW 20375, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2678-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3240 BP 323 EP 329 DI 10.1117/12.300069 PG 7 WC Engineering, Biomedical; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BK57V UT WOS:000072611900033 ER PT J AU Dufrene, YF Boland, T Schneider, JW Barger, WR Lee, GU AF Dufrene, YF Boland, T Schneider, JW Barger, WR Lee, GU TI Characterization of the physical properties of model biomembranes at the nanometer scale with the atomic force microscope SO FARADAY DISCUSSIONS LA English DT Article ID ELECTRICAL DOUBLE-LAYER; PHOSPHOLIPID-BILAYERS; AQUEOUS-SOLUTIONS; HYDRATION FORCES; PHOSPHATIDYLETHANOLAMINE BILAYERS; ELECTROLYTE-SOLUTIONS; AMPHIPHILIC SURFACES; ADHESION FORCES; LIPID BILAYERS; MONOLAYERS AB Interaction forces and topography of mixed phospholipid-glycolipid bilayers were investigated by atomic force microscopy (AFM) in aqueous conditions with probes functionalized with self-assembled monolayers terminating in hydroxy groups. Short-range repulsive forces were measured between the hydroxy-terminated probe and the surface of the two-dimensional (2-D) solid-like domains of distearoyl-phosphatidylethanolamine (DSPE) and digalactosyldiglyceride (DGDG). The form and range of the short-range repulsive force indicated that repulsive hydration/steric forces dominate the interaction at separation distances of 0.3-1.0 nm after which the probe makes mechanical contact with the bilayers. At loads <5 nN the bilayer was elastically deformed by the probe, while at higher loads plastic deformation of the bilayer was observed. Surprisingly, a short-range repulsive force was not observed at the surface of the 2-D liquid-like dioleoylphosphatidylethanolamine(DOPE) film, despite the identical head groups of DOPE and DSPE. This provides direct evidence for the influence of the structure and mechanical properties of lipid bilayers on their interaction forces, an effect which may be of major importance in the control of biological processes such as cell adhesion and membrane fusion. The step height measured between lipid domains in the AFM topographic images was larger than could be accounted for by the thickness and mechanical properties of the molecules. A direct correlation was observed between the repulsive force range over the lipid domains and the topographic contrast, which provides direct insight into the fundamental mechanisms of AFM imaging in aqueous solutions. This study demonstrates that chemically modified AFM probes can be used in combination with patterned lipid bilayers as a novel and powerful approach to characterize the nanometer scale chemical and physical properties of heterogeneous biosurfaces such as cell membranes. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. Univ Maryland, Columbus Ctr, Ctr Marine Biotechnol, Baltimore, MD 21202 USA. RP Dufrene, YF (reprint author), Univ Catholique Louvain, Unite Chim Interfaces, Pl Croix Sud 2-18, B-1348 Louvain, Belgium. RI Schneider, James/C-4095-2008; Lee, Gil/P-8696-2016 OI Schneider, James/0000-0001-8016-8687; Lee, Gil/0000-0002-7949-5848 NR 69 TC 95 Z9 96 U1 2 U2 21 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0301-7249 J9 FARADAY DISCUSS JI Faraday Discuss. PY 1998 VL 111 BP 79 EP 94 PG 16 WC Chemistry, Physical SC Chemistry GA 208CD UT WOS:000080971900007 PM 10822601 ER PT J AU McCormack, DA Kroes, GJ Baerends, EJ Mowrey, RC AF McCormack, DA Kroes, GJ Baerends, EJ Mowrey, RC TI Six-dimensional quantum dynamics of dissociation of rotationally excited H-2 on Cu(100) SO FARADAY DISCUSSIONS LA English DT Article ID POTENTIAL-ENERGY SURFACE; LONG PROPAGATION TIMES; WAVE-PACKET CALCULATIONS; CU(111) SURFACE; ASSOCIATIVE DESORPTION; TRANSLATIONAL ENERGY; GRADIENT CORRECTIONS; REACTIVE SCATTERING; DIATOMIC MOLECULE; NI-SURFACES AB Six-dimensional wavepacket calculations are performed for dissociative adsorption of H-2 on Cu(100) at normal incidence. The potential-energy surface (PES) is an improved fit to points calculated using density functional theory, with the generalized gradient approximation and a slab representation for the surface. The dependence of the reaction probability on incidence energy is determined for the initial rovibrational states (v = 0, j = 0), (v = 0, j = 4, m(j) = 0) and (v = 0, j = 4, m(j) = 4). Owing to the use of an improved 0, of the PES, the computed reaction probability for (v = 0, j = 0) H-2 is in better agreement with experiment than earlier 6D results for this system. At low collision energies rotational motion enhances the reaction, and taking this into account in the theoretical analysis should improve the agreement with existing molecular beam experiments. The reaction of the 'helicopter' (j = 4, m(j) = 4) state is found to be more efficient than that of the 'cartwheel' (j = 4, m(j) = 0) state for most of the collision energies considered. C1 Free Univ Amsterdam, NL-1081 HV Amsterdam, Netherlands. USN, Res Lab, Theoret Chem Sect, Washington, DC 20375 USA. Leiden Univ, Gorlaeus Labs, Leiden Inst Chem, NL-2300 RA Leiden, Netherlands. RP McCormack, DA (reprint author), Leiden Univ, Gorlaeus Labs, Leiden Inst Chem, POB 9502, NL-2300 RA Leiden, Netherlands. RI Baerends, Evert Jan/F-7206-2011 OI Baerends, Evert Jan/0000-0002-3045-4906 NR 63 TC 23 Z9 23 U1 0 U2 6 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0301-7249 J9 FARADAY DISCUSS JI Faraday Discuss. PY 1998 VL 110 BP 267 EP 285 DI 10.1039/a804213f PG 19 WC Chemistry, Physical SC Chemistry GA 148EP UT WOS:000077492000014 ER PT S AU Carter, AC Horwitz, JS Chrisey, DB Pond, JM Kirchoefer, SW Chang, WT Loferski, P AF Carter, AC Horwitz, JS Chrisey, DB Pond, JM Kirchoefer, SW Chang, WT Loferski, P BE Treece, RE Jones, RE Foster, CM Desu, SB Yoo, IK TI The effects of high temperature annealing and composition on the dielectric properties of thin films of BaxSrzTiO3 SO FERROELECTRIC THIN FILMS VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Ferroelectric Thin Films VI Symposium, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc AB Single phase, (100) oriented Ba0.5Sr0.5TiO3 films have been deposited by pulsed laser deposition onto (100) LaAlO3, SrTiO3, MgO substrates. The dielectric properties of these films were measured using interdigitated capacitors as a function of DIC bias and temperature at 1 MHz and as a function of DC bias at 1 to 20 GHz at room temperature. Deposited films were annealed over a temperature range of 900 to 1350 C for 1 to 8 hours to observe its effect on dielectric properties. Chemical analysis on films deposited from stoichiometric targets showed the films to be up to 6% deficient in Ba and Sr under typical PLD deposition conditions. Optimal annealing conditions and target stoichiometries for minimizing dielectric loss and maximizing tuning are discussed. C1 USN, Res Lab, Washington, DC 20375 USA. RP Carter, AC (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-398-3 J9 MATER RES SOC SYMP P PY 1998 VL 493 BP 347 EP 352 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BL02Z UT WOS:000074085900053 ER PT S AU Chang, WT Carter, AC Horwitz, JS Kirchoefer, SW Pond, JM Grabowski, KS Chrisey, DB AF Chang, WT Carter, AC Horwitz, JS Kirchoefer, SW Pond, JM Grabowski, KS Chrisey, DB BE Treece, RE Jones, RE Foster, CM Desu, SB Yoo, IK TI Dielectric and structural properties of (100)KTa1-xNbxO3 films grown on MgO, LaAlO3 and SrTiO3 substrates by pulsed laser deposition SO FERROELECTRIC THIN FILMS VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Ferroelectric Thin Films VI Symposium, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc AB KTa1-xNbxO3 (KTN) thin films (similar to 6000 Angstrom) were grown on (100) MgO, (100) LaAlO3 (LAO), and (100) SrTiO3, (STO) substrates by pulsed laser deposition (PLD). Deposited films were smooth, single phase and exclusively (100) oriented. KTN films deposited on MgO and LAO substrates were easily cracked after deposition or post deposition heat treatment. The film deformation appeared to be caused by strain due to the lattice mismatch between the film and the substrate. A thin buffer layer of similar to 100 Angstrom, was used to eliminate the cracking problem. The high volatility of K at the film deposition temperature required excess K to be added to the ablation target. Sintering of the target and post-deposition annealing of the films were done in a sealed Pt coated stainless steel container. Rutherford backscattering showed the films to have a 1 to 1 atomic ratio of K to Ta + Nb. On top of the KTN films, Ag interdigitated capacitors were deposited. Room temperature measurements of capacitance and dielectric loss as a function of bias electric field (0-80 kV/cm) at 1 to 20 GHz were made. Capacitance and dielectric loss measurements were made as a function of temperature and bias electric field at one MHz and as a function of temperature and frequency at 0V DC bias. The results show the strong potential of KTN for use in frequency agile microwave electronics. C1 USN, Res Lab, Washington, DC 20375 USA. RP Chang, WT (reprint author), USN, Res Lab, Code 6670,4555 Overlook Ave SW, Washington, DC 20375 USA. OI Grabowski, Kenneth/0000-0003-0816-001X NR 0 TC 6 Z9 6 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-398-3 J9 MATER RES SOC SYMP P PY 1998 VL 493 BP 353 EP 358 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BL02Z UT WOS:000074085900054 ER PT J AU Kavarnos, GJ Robinson, HC Holman, RW AF Kavarnos, GJ Robinson, HC Holman, RW TI Calculations of the elastic compliance and piezoelectric constants of poly(vinylidene fluoride) and poly(vinylidene fluoride-trifluoroethylene) crystals SO FERROELECTRICS LA English DT Article ID TRIFLUOROETHYLENE COPOLYMERS AB We present calculated compliance and piezoelectric constants for polyvinylidene fluoride (PVDF) and its copolymer with trifluoroethylene P(VDF/TrFE). The constants were derived by minimizing the energy of the unit cell under various slates of stress, using a modified molecular mechanics force field. The model was first validated against experimental data and theoretical calculations for the properties of PVDF. The behavior of the compliance and piezoelectric constants of P(VDF/TrFE) are examined as a function of the molecular percentage of VDF. It was found that an optimum value for the dielectric constant d(33) of P(VDF-TrFE) exists between 55 and 65 mol % VDF. C1 USN, Undersea Warfare Ctr Detachment, New London, CT 06320 USA. Western Kentucky Univ, Dept Chem, Bowling Green, KY 42101 USA. RP Kavarnos, GJ (reprint author), USN, Undersea Warfare Ctr Detachment, New London, CT 06320 USA. NR 12 TC 3 Z9 3 U1 3 U2 6 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0015-0193 J9 FERROELECTRICS JI Ferroelectrics PY 1998 VL 205 IS 1-4 BP 133 EP 145 DI 10.1080/00150199808228393 PG 13 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA YY817 UT WOS:000072188400012 ER PT J AU Lieberman, SH AF Lieberman, SH TI Direct-push, fluorescence-based sensor systems for in situ measurement of petroleum hydrocarbons in soils SO FIELD ANALYTICAL CHEMISTRY AND TECHNOLOGY LA English DT Review DE fluorescence; sensor; petroleum hydrocarbons; soil; cone penetrometer; laser-induced fluorescence; in situ measurement ID LASER AB By coupling fluorescence-based spectroscopic methods with a probe that can be pushed into the ground to depths of 50 m, it is now possible to make realtime, in situ measurements of chemical contaminants in subsurface environments. Because this optical technique makes use of a laser, or other light source, to induce an optical response in the target analyte, analysis times are extremely fast, usually on the order of seconds. With this technology it is possible to make measurements nearly continuously as the probe is pushed into the ground. The capability for real-time, high-spatial-resolution chemical measurement in the subsurface represents a significant improvement over traditional methods that have been used to delineate subsurface contamination. In this article the status of direct-push, fluorescence-based sensor systems that have been developed for the detection of petroleum hydrocarbon contamination in soils is reviewed. An overview of the common elements of the sensing scheme is provided. Important differences in the configuration of various systems developed to date are summarized. Finally, the effect of key variables on overall system capability is discussed and the status of the acceptance of this technology by the regulatory community is addressed. (C) 1998 John Wiley & Sons, Inc. C1 USN, Space & Naval Warfare Syst Ctr, San Diego, CA 92152 USA. RP Lieberman, SH (reprint author), USN, Space & Naval Warfare Syst Ctr, SSC San Diego,Code D361, San Diego, CA 92152 USA. NR 37 TC 11 Z9 11 U1 0 U2 5 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 1086-900X J9 FIELD ANAL CHEM TECH JI Field Anal. Chem. Technol. PY 1998 VL 2 IS 2 BP 63 EP 73 DI 10.1002/(SICI)1520-6521(1998)2:2<63::AID-FACT2>3.0.CO;2-F PG 11 WC Chemistry, Analytical; Environmental Sciences; Instruments & Instrumentation SC Chemistry; Environmental Sciences & Ecology; Instruments & Instrumentation GA ZJ484 UT WOS:000073220300002 ER PT J AU Elam, WT Adams, JW Hudson, KR McDonald, B Gilfrich, JV AF Elam, WT Adams, JW Hudson, KR McDonald, B Gilfrich, JV TI Subsurface measurement of soil heavy-metal concentrations with the SCAPS X-ray fluorescence (XRF) metals sensor SO FIELD ANALYTICAL CHEMISTRY AND TECHNOLOGY LA English DT Article DE soils; heavy metals; x-ray fluorescence AB A heavy-metals sensor for measurement of subsurface soil contamination was constructed and demonstrated in the field. The sensor operates via x-ray fluorescence (XRF) to detect metals heavier than calcium in the periodic table and provide semiquantitative information with little spectral interference and straightforward spectral interpretation. A description of the sensor is followed by details of the calibration methods and some typical field results. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Washington, DC 20375 USA. USA, Engineer Waterways Expt Stn, Vicksburg, MS 39180 USA. SFA Inc, Landover, MD 20785 USA. Univ Toledo, Toledo, OH 43606 USA. RP Adams, JW (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 4 TC 4 Z9 4 U1 2 U2 6 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1086-900X J9 FIELD ANAL CHEM TECH JI Field Anal. Chem. Technol. PY 1998 VL 2 IS 2 BP 97 EP 102 PG 6 WC Chemistry, Analytical; Environmental Sciences; Instruments & Instrumentation SC Chemistry; Environmental Sciences & Ecology; Instruments & Instrumentation GA ZJ484 UT WOS:000073220300005 ER PT J AU Shaffer, RE Rose-Pehrsson, SL McGill, RA AF Shaffer, RE Rose-Pehrsson, SL McGill, RA TI Multiway analysis of preconcentrator-sampled surface acoustic wave chemical sensor array data SO FIELD ANALYTICAL CHEMISTRY AND TECHNOLOGY LA English DT Article DE pattern recognition; chemometrics; chemical sensor; surface acoustic wave; nerve agent; preconcentration ID PATTERN-RECOGNITION; TEMPERATURE; REDUCTION; COATINGS AB New data processing methods for preconcentrator-sampled surface acoustic wave (SAW) sensor arrays are described. The preconcentrator-sampling procedure is used to collect and concentrate analyte vapors on a porous solid sorbent, Subsequent thermal desorption provides a crude chromatographic separation of the collected vapors prior to exposure to the SAW array. This article describes experiments to test the effects of incorporating retention information into the pattern-recognition procedures and to explore the feasibility of multiway classification methods. Linear discriminant analysis (LDA) and nearest-neighbor (NN) pattern-recognition models are built to discriminate between SAW sensor array data for four toxic organophosphorus chemical agent vapors and one agent simulant collected under a wide variety of conditions. Classification results are obtained for three types of patterns: (a)first-order patterns; (b) first-order patterns augmented with the time of the largest peak; and (c) second-order patterns with the use of the SAW frequency for each sensor over a broad time window. Classification models for the second-order patterns are also developed with the use of unfolded and multiway partial least-squares discriminants (uPLSD and mPLSD) and NN and LDA of the scores from unfolded and multiway principal-component analysis (uPCA and mPCA), It is determined that classification performance improves when information about the desorption time is included, Treating the preconcentrator-sampled SAW sensor array as a second-order analytical instrument and using a classification model based upon either uPLSD, uPCA-LDA, or NN results in the correct identification of 100% of the patterns in the prediction set. With the second-order patterns, the other pattern-recognition algorithms only do slightly worse. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Shaffer, RE (reprint author), USN, Res Lab, Div Chem, Code 6116, Washington, DC 20375 USA. EM shaffer@ccf.nrl.navy.mil RI Shaffer, Ronald/I-2134-2012 NR 19 TC 27 Z9 27 U1 0 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1086-900X J9 FIELD ANAL CHEM TECH JI Field Anal. Chem. Technol. PY 1998 VL 2 IS 3 BP 179 EP 192 DI 10.1002/(SICI)1520-6521(1998)2:3<179::AID-FACT7>3.0.CO;2-Q PG 14 WC Chemistry, Analytical; Environmental Sciences; Instruments & Instrumentation SC Chemistry; Environmental Sciences & Ecology; Instruments & Instrumentation GA ZU831 UT WOS:000074239900007 ER PT J AU Kusterbeck, AW Charles, PT AF Kusterbeck, AW Charles, PT TI Field demonstration of a portable flow immunosensor SO FIELD ANALYTICAL CHEMISTRY AND TECHNOLOGY LA English DT Article DE biosensor; immunoassay; explosives detection; on-site analysis ID EXPLOSIVES TNT; ASSAY AB A portable biosensor known as the FAST 2000, developed by the Naval Research Laboratory (NRL) and engineered by Research International, Inc., has been field tested for effectiveness in performing on-site analyses for two selected explosives, TNT and RDX. The biosensor uses antibody recognition of analyte molecules and subsequent fluorescence detection downstream to measure contaminant levels in groundwater and soil. In field trials at military bases identified by the U. S. EPA as priority Superfund cleanup sites, samples containing unknown concentrations of explosives were collected from groundwater monitoring wells at various locations and analyzed in the NRL sensor with no sample pretreatment or concentration. Test sites included the Volunteer Army Ammunition Plant, Chattanooga, TN and Umatilla Army Depot Activity, Umatilla, OR. Field samples were analyzed on-site by the portable FAST 2000, and splits were analyzed by an independent U. S. EPA-certified laboratory with the use of HPLC SW846 Method 8330. Results demonstrated that the FAST 2000 can detect explosives in environmental samples with accuracy and precision. Statistical analyses based on regression curves comparing the FAST 2000 and HPLC methods showed a high degree of correlation, with r(2) values between 0.86 and 0.97. The assay system required small sample volumes (150 mu l/test) and samples were analyzed in less than 3 min. The sensor was quantitative, with a method detection limit (MDL) of 10 mu g/l. Beyond contaminated field samples, appropriate controls, blanks, and interferents were tested in the lab for certification and validation data requirements. Results were evaluated based on accuracy, precision, cost, time, and waste generation. (C) John Wiley & Sons, Inc. C1 USN, Ctr Biomol Sci & Engn, Res Lab, Washington, DC 20375 USA. RP Kusterbeck, AW (reprint author), USN, Ctr Biomol Sci & Engn, Res Lab, Code 6910,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 8 TC 16 Z9 16 U1 0 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1086-900X J9 FIELD ANAL CHEM TECH JI Field Anal. Chem. Technol. PY 1998 VL 2 IS 6 BP 341 EP 350 DI 10.1002/(SICI)1520-6521(1998)2:6<341::AID-FACT4>3.0.CO;2-X PG 10 WC Chemistry, Analytical; Environmental Sciences; Instruments & Instrumentation SC Chemistry; Environmental Sciences & Ecology; Instruments & Instrumentation GA 147NV UT WOS:000077574100004 ER PT B AU Schneidewind, NF AF Schneidewind, NF GP IEEE IEEE TI An integrated process and product model SO FIFTH INTERNATIONAL SOFTWARE METRICS SYMPOSIUM - METRICS 1998, PROCEEDINGS LA English DT Proceedings Paper CT 5TH International Symposium on Software Metrics (METRICS 1998 CY NOV 20-21, 1998 CL BETHESDA, MD SP IEEE Comp Soc Tech Council Software Engn, IEEE ID SOFTWARE AB The relationship between product quality and process capability and maturity has been recognized as a major issue in software engineering based on the premise that improvements in process will lead to higher quality products. To this end, we have been investigating an important facet of process capability - stability - as defined and evaluated by trend, change, and shape metrics, across releases and within a release. Our integration of product and process measurement and evaluation serves the dual purpose of using metrics to assess and predict reliability and risk and concurrently using these metrics for process stability evaluation. We use the NASA Space Shuttle flight software to illustrate our approach. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Schneidewind, NF (reprint author), USN, Postgrad Sch, Code IS-Ss, Monterey, CA 93943 USA. NR 10 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-8186-9201-4 PY 1998 BP 224 EP 234 PG 11 WC Computer Science, Software Engineering SC Computer Science GA BM29Z UT WOS:000078318100028 ER PT B AU Kuciauskas, AP Brody, LR Hadjimichael, M Bankert, RL Tag, PM Peak, JE AF Kuciauskas, AP Brody, LR Hadjimichael, M Bankert, RL Tag, PM Peak, JE GP AMER METEOROL SOC AMER METEOROL SOC TI MEDEX: Applying fuzzy logic to a meteorological expert system SO FIRST CONFERENCE ON ARTIFICIAL INTELLIGENCE LA English DT Proceedings Paper CT 1st Conference on Artificial Intelligence at the 78th American-Meteorological-Society Annual Meeting CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Res Lab, Monterey, CA 93940 USA. RP Kuciauskas, AP (reprint author), USN, Res Lab, Monterey, CA 93940 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 68 EP 74 PG 7 WC Computer Science, Artificial Intelligence; Meteorology & Atmospheric Sciences SC Computer Science; Meteorology & Atmospheric Sciences GA BL80F UT WOS:000076779400018 ER PT B AU Tag, PM Bankert, RL AF Tag, PM Bankert, RL GP AMER METEOROL SOC AMER METEOROL SOC TI Worldwide AVHRR cloud classifiers, valid for both water and land, day and night SO FIRST CONFERENCE ON ARTIFICIAL INTELLIGENCE LA English DT Proceedings Paper CT 1st Conference on Artificial Intelligence at the 78th American-Meteorological-Society Annual Meeting CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Res Lab, Monterey, CA 93943 USA. RP Tag, PM (reprint author), USN, Res Lab, 7 Grace Hopper Ave, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 96 EP 101 PG 6 WC Computer Science, Artificial Intelligence; Meteorology & Atmospheric Sciences SC Computer Science; Meteorology & Atmospheric Sciences GA BL80F UT WOS:000076779400025 ER PT B AU Hadjimichael, M Tag, PM Bankert, RL AF Hadjimichael, M Tag, PM Bankert, RL GP AMER METEOROL SOC AMER METEOROL SOC TI Discovering model bias in the determination of cloud base height SO FIRST CONFERENCE ON ARTIFICIAL INTELLIGENCE LA English DT Proceedings Paper CT 1st Conference on Artificial Intelligence at the 78th American-Meteorological-Society Annual Meeting CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Res Lab, Monterey, CA 93943 USA. RP Hadjimichael, M (reprint author), USN, Res Lab, 7 Grace Hopper Ave, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP J5 EP J8 PG 4 WC Computer Science, Artificial Intelligence; Meteorology & Atmospheric Sciences SC Computer Science; Meteorology & Atmospheric Sciences GA BL80F UT WOS:000076779400039 ER PT B AU Patrick, D Hoekstra, R AF Patrick, D Hoekstra, R BE Wickramanayake, GB Hinchee, RE TI Plume stabilization using pump and treat technology SO FIRST INTERNATIONAL CONFERENCE ON REMEDIATION OF CHLORINATED AND RECALCITRANT COMPOUNDS, VOL 5: PHYSICAL, CHEMICAL AND THERMAL TECHNOLOGIES LA English DT Proceedings Paper CT 1st International Conference on Remediation of Chlorinated and Recalcitrant Compounds CY MAY 18-21, 1998 CL MONTEREY, CA AB Pump and treat technology was used to stabilize a chlorinated solvent plume at a U.S. Navy site in Key West, Florida. Solvents were routinely released for many years to the soil surrounding the site, a former jet engine test facility. Concentrations of trichloroethylene (TCE), cis 1,2-, and trans 1,2-dichloroethylene (DCE) were found in the range of 3-41. microgram/liter (mu/L), 74-1560 mu g/L, and 170-2800 mu g/L, respectively. The Navy provided evidence that the plume was naturally biodegrading and therefore proposed natural attenuation as a final remedy. The Environmental Protection Agency (EPA) Region IV and Florida's Department of Environmental Protection (FDEP) rejected the proposal, directing instead thar the Navy begin immediately to address the solvent plume, which was migrating towards a large saltwater inlet, connected to the Atlantic Ocean. The Navy designed and installed a simple pump and treat system. Calculations showed that it would take one to two years to stabilize the plume. Pumping began in July 1996 and was terminated in June 1997 after effluent results demonstrated that objectives had been met. Despite a growing trend towards other technologies, this :much-maligned technology continues to offer Navy engineers and managers an alternate means to address groundwater contaminant problems. C1 USN, Charleston, SC 29408 USA. RP Patrick, D (reprint author), USN, Charleston, SC 29408 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-060-8 PY 1998 BP 217 EP 222 PG 6 WC Chemistry, Multidisciplinary; Engineering, Environmental; Engineering, Chemical; Environmental Sciences; Toxicology SC Chemistry; Engineering; Environmental Sciences & Ecology; Toxicology GA BL54U UT WOS:000075849200034 ER PT B AU Colton, RJ Barger, WR Baselt, DR Corcoran, SG Koleske, DD Lee, GU AF Colton, RJ Barger, WR Baselt, DR Corcoran, SG Koleske, DD Lee, GU BE Olij, WJV Anderson, HR TI Atomic force microscopy: Surface forces, adhesion and nanomechanics measurements SO FIRST INTERNATIONAL CONGRESS ON ADHESION SCIENCE AND TECHNOLOGY - INVITED PAPERS: FESTSCHRIFT IN HONOR OF DR. K.L. MITTAL ON THE OCCASION OF HIS 50TH BIRTHDAY LA English DT Proceedings Paper CT 1st International Congress on Adhesion Science and Technology in Honor of Dr Kash Mittal on his 50th Birthday CY OCT 16-20, 1995 CL AMSTERDAM, NETHERLANDS SP Akzo Nobel, DSM Res, Dow Corning Corp, H F Fuller Co, 3M Co, Procter & Gamble, Adhes Soc Japan, French Chem Soc, Israeli Polymers & Plast Soc, Italian Chem Soc, Royal Dutch Chem Soc, Swedish Chem Soc DE atomic force microscopy; surface forces; adhesion; nanomechanics; nanoindentation; molecular recognition; micromachined sensors; biosensors ID LANGMUIR-BLODGETT MONOLAYERS; SCANNING PROBE MICROSCOPE; GOLD SINGLE-CRYSTALS; TUNGSTEN TIP; RESONATING MICROCANTILEVERS; YIELD-POINT; NANOINDENTATION; FRICTION; FILMS; RESOLUTION AB This paper reviews work conducted at the Naval Research Laboratory to measure surface forces, adhesion and nanomechanical properties of materials using an Atomic Force Microscope (AFM). The article portrays the AFM as an enabling technology, evolving fr om a qualitative picturing-taking tool to a quantitative probe of material!, properties. For example, surface forces can be used to reduce contact forces during imaging, improve image resolution, and change image contrast. Force-distance curves and maps can be used to correlate surface topography with the adhesion, surface energy, frictional and mechanical properties of materials. Applications presented include imaging phase-segregated Langmuir-Blodgett films, measuring molecular recognition forces between individual molecules, determining the absolute modulus of materials from nanoindentation, and studying the nucleation of dislocations. Finally, the evolution of the AFM towards, dedicated micromachined instruments and sensors for on-line process control and sensing applications is introduced. C1 USN, Res Lab, Washington, DC 20375 USA. RP Colton, RJ (reprint author), USN, Res Lab, Code 6177, Washington, DC 20375 USA. RI Lee, Gil/P-8696-2016 OI Lee, Gil/0000-0002-7949-5848 NR 85 TC 2 Z9 2 U1 2 U2 8 PU VSP BV-C/O BRILL ACAD PUBL PI LEIDEN PA PO BOX 9000, 2300 PA LEIDEN, NETHERLANDS BN 90-6764-291-6 PY 1998 BP 21 EP 47 PG 5 WC Polymer Science SC Polymer Science GA BN02P UT WOS:000080424700002 ER PT S AU Boyer, LL Stokes, HT Mehl, MJ AF Boyer, LL Stokes, HT Mehl, MJ BE Cohen, RE TI Self-consistent atomic deformation calculations for strontium titanate SO FIRST-PRINCIPLES CALCULATIONS FOR FERROELECTRICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 5th Williamsburg Workshop on 1st-Principles Calculations for Ferroelectrics CY FEB 01-04, 1998 CL WILLIAMSBURG, VA SP USN, Off Naval Res, Carnegie Inst Washington AB The self-consistent atomic deformation method employs density functional theory by expressing the total electronic density as a sum over "atomic" densities determined self-consistently from a variational treatment of the total energy. We use this method to compute electronic and vibrational properties of SrTiO3. Certain modes are found to be quite sensitive to the kinetic energy resulting from overlapping densities. We find that enhancing the Thomas-Fermi energy by similar to 4% gives good agreement with experimental results for phonon frequencies and lattice parameter. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Boyer, LL (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-730-8 J9 AIP CONF PROC PY 1998 IS 436 BP 227 EP 237 PG 11 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BL30B UT WOS:000075034000025 ER PT S AU Mazin, II Singh, DJ AF Mazin, II Singh, DJ BE Cohen, RE TI Weighted density functionals for ferroelectric materials SO FIRST-PRINCIPLES CALCULATIONS FOR FERROELECTRICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 5th Williamsburg Workshop on 1st-Principles Calculations for Ferroelectrics CY FEB 01-04, 1998 CL WILLIAMSBURG, VA SP USN, Off Naval Res, Carnegie Inst Washington AB The weighted density approximation, its implementation and its application to Ferroelectric materials is discussed. Calculations are presented for several perovskite oxides anti related materials. In general the weighted density approximation is found to be superior to either the local density or generalized gradient approximation for the ground state. Electronic structures are little changed. The linear response of the weighted density approximation is calculated for the homogeneous electron gas, and found to be improved relative to the local density result, but, not in full agreement with existing Monte Carlo data. It is shown that the agreement can be Further improved by a simple modification. Calculations of the ferroelectric soft mode in KNbO3 suggest that the low temperature distortion is approximately 20% smaller than indicated by existing experiments. C1 USN, Res Lab, Washington, DC 20375 USA. RP Mazin, II (reprint author), USN, Res Lab, Code 6691, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012 NR 0 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-730-8 J9 AIP CONF PROC PY 1998 IS 436 BP 251 EP 264 PG 14 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BL30B UT WOS:000075034000027 ER PT S AU Heitmeyer, C AF Heitmeyer, C BE Ravn, AP Rischel, H TI On the need for practical formal methods SO FORMAL TECHNIQUES IN REAL-TIME AND FAULT-TOLERANT SYSTEMS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 5th International Symposium on Formal Techniques in Real-Time and Fault-Tolerant Systems (FTRTFT 98) CY SEP 14-18, 1998 CL LYNGBY, DENMARK ID VERIFICATION; SYSTEMS AB A controversial issue in the formal methods community is the degree to which mathematical sophistication and theorem proving skills should be needed to apply a formal method. A fundamental assumption of this paper is that formal methods research has produced several classes of analysis that can prove useful in software development. However, to be useful to software practitioners, most of whom lack advanced mathematical training and theorem proving skills, current formal methods need a number of additional attributes, including more user-friendly notations, completely automatic (i.e., pushbutton) analysis, and useful, easy to understand feedback. Moreover, formal methods need to be integrated into a standard development process. I discuss additional research and engineering that is needed to make the current set of formal methods more practical. To illustrate the ideas, I present several examples, many taken from the SCR (Software Cost Reduction) requirements method, a formal method that software developers can apply without theorem proving skills, knowledge of temporal and higher order logics, or consultation with formal methods experts. C1 USN, Res Lab, Washington, DC 20375 USA. RP Heitmeyer, C (reprint author), USN, Res Lab, Code 5546, Washington, DC 20375 USA. RI Heitmeyer, Constance/F-6500-2011 NR 25 TC 25 Z9 25 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65003-2 J9 LECT NOTES COMPUT SC PY 1998 VL 1486 BP 18 EP 26 PG 9 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BN66E UT WOS:000082522000002 ER PT S AU Dunn, DN Wahl, KJ Singer, IL AF Dunn, DN Wahl, KJ Singer, IL BE Moody, NR Gerberich, WW Burnham, N Baker, SP TI Nanostructural aspects of wear in ion-beam deposited Pb-Mo-S films SO FUNDAMENTALS OF NANOINDENTATION AND NANOTRIBOLOGY SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Materials-Research-Society Symposium on Fundamentals of Nanoindentation and Nanotribology CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc, Appl Mat, Santa Clara, CA, Digital Instruments Inc, Santa Barbara, CA, Dow Corning Corp, Midland, Michigan, Hysitron Inc, Minneapolis, Minnesota, Nano Instruments Inc, Oak Ridge, Tennessee AB Microstructural aspects of wear resistance have been investigated using cross-sectional transmission electron microscopy (TEM) to analyze both as-deposited and worn films. As-deposited Pb-Mo-S films were virtually amorphous, i.e., show no long range structure. Wear tracks revealed a two-part wear process localized at the sliding surface. First, Pb-Mo-S at the sliding surface was transformed into basal-oriented, crystalline MoS2 from 1 to 4 monolayers thick. Then, as sliding continued, the MoS2 layers were detached one or two layers at a time. Evidence for the nanometer scale wear process is presented. C1 USN, Res Lab, Tribol Sect, Washington, DC 20375 USA. RP Dunn, DN (reprint author), USN, Res Lab, Tribol Sect, Washington, DC 20375 USA. OI Wahl, Kathryn/0000-0001-8163-6964 NR 0 TC 6 Z9 6 U1 1 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-428-9 J9 MATER RES SOC SYMP P PY 1998 VL 522 BP 451 EP 456 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BL94J UT WOS:000077250000069 ER PT B AU Smith, JF AF Smith, JF BE Arabnia, HR TI A fuzzy logic multisensor association algorithm: Applied to noisy, intermittent and sparse data SO FUSION'98: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MULTISOURCE-MULTISENSOR INFORMATION FUSION, VOLS 1 AND 2 LA English DT Proceedings Paper CT International Conference on Multisource-Multisensor Information Fusion (FUSION 98) CY JUL 06-09, 1998 CL LAS VEGAS, NV SP Comp Sci Res, Educ & Applicat Press, Comp Vis res & applicat Tech, IEEE Signal Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm, USA Night Vis & Electr Sensors Directorate, USA Res Off, USN Off Res, Zaptron Syst Inc DE fuzzy clustering; fuzzy sets; fuzzy logic; recursive; multisensor; association; superclustering; outlier suppression; ESM; radar AB A recursive multisensor association algorithm has been developed based on fuzzy logic. If simultaneously determines fuzzy grades of membership and fuzzy cluster centers. It is capable of associating data from various sensor types and in its simplest form makes no assumption about noise statistics as many association algorithms do. The algorithm is capable of performing without operator intervention. If associates data from the same target for multiple sensor types The algorithm also provides an estimate of the number of targets present, reduced noise estimates of the quantities being measured and a measure of confidence to assign to the data association. A comparison of the algorithm to a more conventional Bayesian association algorithm is provided. The data for both the ESM and radar systems is noisy. Examples are included in which the data has probability of detection less than unify. C1 USN, Res Lab, Tact Elect Warfare Div, Washington, DC 20375 USA. RP Smith, JF (reprint author), USN, Res Lab, Tact Elect Warfare Div, Code 5741,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 8 TC 9 Z9 9 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-02-5 PY 1998 BP 681 EP 688 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Mathematics, Applied SC Automation & Control Systems; Computer Science; Mathematics GA BR81V UT WOS:000167662000098 ER PT B AU Hofmann, JB Jakobovits, RH AF Hofmann, JB Jakobovits, RH BE Arabnia, HR TI Surveillance planning resource optimization using nonlinear data fusion SO FUSION'98: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MULTISOURCE-MULTISENSOR INFORMATION FUSION, VOLS 1 AND 2 LA English DT Proceedings Paper CT International Conference on Multisource-Multisensor Information Fusion (FUSION 98) CY JUL 06-09, 1998 CL LAS VEGAS, NV SP Comp Sci Res, Educ & Applicat Press, Comp Vis res & applicat Tech, IEEE Signal Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm, USA Night Vis & Electr Sensors Directorate, USA Res Off, USN Off Res, Zaptron Syst Inc DE surveillance planning; decision support systems; integer programming; command and control AB An approach to surveillance planning resource optimization based on the no-detection likelihood forecasting features of an associated data fusion algorithm is described. Assuming a law signal-to-noise ratio in the data, the approach focuses on the assignment of processing assets available to a surveillance commander. Generic functions; of a hypothetical Surveillance Center are described along with a set of decision aid algorithms for data fusion and resource optimization. The resource allocation model is described in detail along with several approaches to solving the optimization. Considerations regarding processing resources available and mobile vs. fixed sensors are also explored. The work is based an previously unpublished results obtained in a U. S. Navy-sponsored undersea surveillance Advanced Technology Demonstration (1993). C1 USN, Res Lab, Washington, DC 20375 USA. RP Hofmann, JB (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-02-5 PY 1998 BP 733 EP 740 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Mathematics, Applied SC Automation & Control Systems; Computer Science; Mathematics GA BR81V UT WOS:000167662000106 ER PT B AU Ballas, J Kushnier, S AF Ballas, J Kushnier, S BE Arabnia, HR TI ISART: Interactive situation assessment and rollup tool SO FUSION'98: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MULTISOURCE-MULTISENSOR INFORMATION FUSION, VOLS 1 AND 2 LA English DT Proceedings Paper CT International Conference on Multisource-Multisensor Information Fusion (FUSION 98) CY JUL 06-09, 1998 CL LAS VEGAS, NV SP Comp Sci Res, Educ & Applicat Press, Comp Vis res & applicat Tech, IEEE Signal Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm, USA Night Vis & Electr Sensors Directorate, USA Res Off, USN Off Res, Zaptron Syst Inc DE situation assessment; HCI AB A research program at NRL and NAWCAD has been investigating and developing interface software to supper? collaboration between an experienced user and an AI based software system for situation assessment. A prototype called ISART has been developed which implements an approach to collaborative situation assessment between human and computer. This prototype provides user interface, knowledge base, and inference support for the user to insert situation assessments into a computer system at several levels of abstraction. The system represents these abstractions in a knowledge base and on the screen, and carl reason about and make recommendations for tactical action. Two interface capabilities are unique in ISART: Intelligent Aggregation and Mission Widgets. The first lets the user roll up units into forces. The second lets the user generate and manipulate graphic mission representations. C1 USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. RP Ballas, J (reprint author), USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-02-5 PY 1998 BP 937 EP 944 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Mathematics, Applied SC Automation & Control Systems; Computer Science; Mathematics GA BR81V UT WOS:000167662000136 ER PT J AU Szpak, S Mosier-Boss, PA Boss, RD Smith, JJ AF Szpak, S Mosier-Boss, PA Boss, RD Smith, JJ TI On the behavior of the Pd/D system: Evidence for tritium production SO FUSION TECHNOLOGY LA English DT Article DE Pd/D system; tritium production ID SEARCH AB Evidence for tritium production in the Pd/D system under cathodic polarization is presented. A comparison of the observed distribution and that calculated, based on the conservation of mass, leads to the conclusion that tritium is produced sporadically at an estimated rate of similar to 10(3) to 10(4) atom/s. The results of several runs are interpreted by employing the concept of an electrode/electrolyte interphase and the accepted kinetics of hydrogen evolution. Burstlike events followed by longer periods of inactivity yield poor reproducibility when distributions are averaged over the total time of electrolysis. C1 USN, Command Control & Ocean Surveillance Ctr, RDT&E Div, San Diego, CA 92152 USA. US DOE, Washington, DC 20585 USA. RP Szpak, S (reprint author), USN, Command Control & Ocean Surveillance Ctr, RDT&E Div, San Diego, CA 92152 USA. NR 14 TC 14 Z9 14 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD JAN PY 1998 VL 33 IS 1 BP 38 EP 51 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA YU381 UT WOS:000071711400004 ER PT S AU Share, GH Matz, SM AF Share, GH Matz, SM BE Meegan, CA Preece, RD Koshut, TM TI High-energy spectral evolution in cosmic gamma-ray bursts SO GAMMA-RAY BURSTS, PTS 1 AND 2 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 4th Huntsville Gamma-Ray Burst Symposium CY SEP 15-20, 1997 CL HUNTSVILLE, AL SP Univ Space Res Assoc AB We have studied spectral evolution at 2 a resolution in 48 strong bursts observed by the Solar Maximum Mission (SMM) Gamma Ray Spectrometer (GRS). Hard-to-soft spectral evolution is observed in individual pulses in 30 of the events; there are no clear instances of soft-to-hard evolution in resolved pulses but; hardness appears to track intensity in some events. There is also no consistent trend of softening from one pulse to the next. Twenty of the Bursts were observed >4 MeV and these exhibit the same spectral evolution as the full sample. We present in greater detail data from 8 of 14 bursts detected at energies >10 MeV. Pulses observed >10 MeV are generally narrower than they are at 0.3 MeV and they typically exhibit hard-to-soft spectral evolution, although hardness appears to track intensity in two of the events. In two of the bursts, later pulses are either as hard or considerably harder than earlier pulses. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Share, GH (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7652, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-766-9 J9 AIP CONF PROC PY 1998 IS 428 BP 354 EP 358 PG 5 WC Astronomy & Astrophysics; Remote Sensing SC Astronomy & Astrophysics; Remote Sensing GA BL28Z UT WOS:000075012200070 ER PT S AU Vrba, FJ Luginbuhl, CB Jennings, MC Hartmann, DH Hurley, KC Kouveliotou, C Meegan, CA Fishman, G Cline, TL Boer, M AF Vrba, FJ Luginbuhl, CB Jennings, MC Hartmann, DH Hurley, KC Kouveliotou, C Meegan, CA Fishman, G Cline, TL Boer, M BE Meegan, CA Preece, RD Koshut, TM TI The USNO Deep Optical Survey of small IPN3 localizations: Where are the hosts? SO GAMMA-RAY BURSTS, PTS 1 AND 2 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 4th Huntsville Gamma-Ray Burst Symposium CY SEP 15-20, 1997 CL HUNTSVILLE, AL SP Univ Space Res Assoc AB We present a summary of our deep optical photometric surveys of five small (< 8 arcmin(2)) IPN3 GRB localizations at high Galactic latitude (b(II) > 25 degrees). All of the localizations contain galaxies ranging in brightness from V similar to 18 to our survey limits at about V similar to 23. Without model-dependent assumptions of acceptable GRB distances, these galaxies, which are several magnitudes brighter than the galaxy associated with the GRB970228 optical transient, are viable GRB host candidates. We find a QSO candidate in only one of the localizations, and are therefore unable to support the hypothesis, based on larger IPN1 localizations, that QSO/AGNs or blue galaxies may be associated with GRBs [1,2]. We examine possible reasons for this negative result. C1 USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Vrba, FJ (reprint author), USN Observ, Flagstaff Stn, POB 1149, Flagstaff, AZ 86002 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-766-9 J9 AIP CONF PROC PY 1998 IS 428 BP 625 EP 629 PG 5 WC Astronomy & Astrophysics; Remote Sensing SC Astronomy & Astrophysics; Remote Sensing GA BL28Z UT WOS:000075012200121 ER PT S AU Vrba, FJ Luginbuhl, CB Hartmann, DH Jennings, MC AF Vrba, FJ Luginbuhl, CB Hartmann, DH Jennings, MC BE Meegan, CA Preece, RD Koshut, TM TI Deep imaging of the IPN1 localization of GRB790325 (GBS 1810+31) SO GAMMA-RAY BURSTS, PTS 1 AND 2 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 4th Huntsville Gamma-Ray Burst Symposium CY SEP 15-20, 1997 CL HUNTSVILLE, AL SP Univ Space Res Assoc AB The IPN1 localization of GRB790325 is one of the smallest GRB localizations, but it has been poorly surveyed due to the nearby bright star 104 Her. We have used a new camera employing a Tek 2048(2) CCD with a 9 magnitude NE apodizing region to block the light of 104 Her and obtain deep UBVI imaging of the localization. The observations, obtained at the USNO 1.55-m telescope, are the deepest yet obtained of this localization, revealing 20 objects clearly in or at the edge of the error box. Among these is a QSO candidate which is unlikely to be located randomly within the localization based on known QSO statistics. C1 USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Vrba, FJ (reprint author), USN Observ, Flagstaff Stn, POB 1149, Flagstaff, AZ 86002 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-766-9 J9 AIP CONF PROC PY 1998 IS 428 BP 630 EP 634 PG 5 WC Astronomy & Astrophysics; Remote Sensing SC Astronomy & Astrophysics; Remote Sensing GA BL28Z UT WOS:000075012200122 ER PT S AU Wolf, SA AF Wolf, SA BE Bok, J Deutscher, G Pavuna, D Wolf, SA TI Applications of HTS to space and electronics SO GAP SYMMETRY AND FLUCTUATIONS IN HIGH-T(C) SUPERCONDUCTORS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES B, PHYSICS LA English DT Proceedings Paper CT NATO Advanced Study Institute on the Gap Symmetry and Fluctuations in High-T(c) Superconductors CY SEP 01-13, 1997 CL CARGESE, FRANCE SP NATO, Sci Div C1 USN, Res Lab, Washington, DC 20375 USA. RP Wolf, SA (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0258-1221 BN 0-306-45934-5 J9 NATO ADV SCI I B-PHY PY 1998 VL 371 BP 185 EP 193 PG 9 WC Physics, Condensed Matter SC Physics GA BL99F UT WOS:000077391900012 ER PT B AU Buchanan, JL Gilbert, RP AF Buchanan, JL Gilbert, RP BE Florian, H Hackl, K Schnitzer, FJ Tutschke, W TI Comparison of the parabolic approximation with residue calculus in ocean acoustics SO GENERALIZED ANALYTIC FUNCTIONS: THEORY AND APPLICATIONS TO MECHANICS SE INTERNATIONAL SOCIETY FOR ANALYSIS, APPLICATIONS AND COMPUTATION LA English DT Proceedings Paper CT Conference on Generalized Analytic Functions - Theory and Applications CY JAN 06-10, 1997 CL GRAZ, AUSTRIA AB The usual implementation of the numerical technique for approximating far field acoustic pressure in the ocean known as parabolic approximation will be unstable for some poroelastic sediments. This instability can be remedied if a certain conjecture is true. Moreover the resulting solutions are in good agreement with analytical solutions obtained by an application of the residue calculus. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. RP Buchanan, JL (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5043-X J9 INT SOC ANAL APP COM PY 1998 VL 1 BP 241 EP 253 PG 13 WC Acoustics; Limnology; Mathematics, Applied; Mechanics; Physics, Mathematical SC Acoustics; Marine & Freshwater Biology; Mathematics; Mechanics; Physics GA BL70Q UT WOS:000076400900021 ER PT J AU Sellers, WR Novitch, BG Miyake, S Heith, A Otterson, GA Kaye, FJ Lassar, AB Kaelin, WG AF Sellers, WR Novitch, BG Miyake, S Heith, A Otterson, GA Kaye, FJ Lassar, AB Kaelin, WG TI Stable binding to E2F is not required for the retinoblastoma protein to activate transcription, promote differentiation, and suppress tumor cell growth SO GENES & DEVELOPMENT LA English DT Article DE retinoblastoma; transcription; E2F; tumorigenesis ID ONCOGENIC POINT MUTATIONS; SKELETAL-MUSCLE CELLS; CYCLIN-E GENE; FAMILY MEMBERS; GLUCOCORTICOID RECEPTOR; INCOMPLETE PENETRANCE; RB-1 GENE; P107; PRODUCT; PRB AB The retinoblastoma tumor suppressor protein (pRB) can inhibit cell cycle progression and promote differentiation. pRB interacts with a variety of transcription factors, including members of the E2F and C-EBP protein families and MyoD, and can either repress or activate transcription depending on the promoter under study. These biological and biochemical activities of pRB have been mapped previously to a core domain, referred to as the pRB pocket. Using a panel of synthetic pRB pocket mutants, we found that the acute induction of a G(1)/S block by pRB is linked to its ability to both bind to E2F and to repress transcription. In contrast, these functions were not required for pRB to promote differentiation, which correlated with its ability to activate transcription in concert with fate-determining proteins such as MyoD. All tumor-derived PRE mutants tested to date failed to bind to E2F and did not repress transcription. Despite an inability to bind to E2F, pRB mutants associated with a low risk of retinoblastoma, unlike high-risk mutants, retained the ability to activate transcription and promote differentiation. Thus, the pRB pocket participates in dual tumor suppressor functions, one linked to cell cycle progression and the other to differentiation control, and these functions can be genetically and mechanistically dissociated. C1 Dana Farber Canc Inst, Boston, MA 02115 USA. Harvard Univ, Sch Med, Dept Biol Chem & Mol Pharmacol, Boston, MA 02115 USA. NCI, USN, Med Oncol Branch, Div Clin Sci, Bethesda, MD 20889 USA. RP Kaelin, WG (reprint author), Dana Farber Canc Inst, Boston, MA 02115 USA. RI kaye, frederic/E-2437-2011; OI Novitch, Bennett/0000-0002-2696-3708 NR 59 TC 248 Z9 254 U1 1 U2 3 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 0890-9369 J9 GENE DEV JI Genes Dev. PD JAN 1 PY 1998 VL 12 IS 1 BP 95 EP 106 DI 10.1101/gad.12.1.95 PG 12 WC Cell Biology; Developmental Biology; Genetics & Heredity SC Cell Biology; Developmental Biology; Genetics & Heredity GA YR072 UT WOS:000071455400010 PM 9420334 ER PT B AU Harris, HC Silbermann, NA Smith, HA AF Harris, HC Silbermann, NA Smith, HA BE Bradley, PA Guzik, JA TI Variable stars in the Draco dwarf spheroidal galaxy SO HALF CENTURY OF STELLAR PULSATION INTERPRETATIONS: A TRIBUTE TO ARTHUR N. COX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on a Half Century of Stellar Pulsation Interpretations CY JUN 16-20, 1997 CL LOS ALAMOS, NM AB A new survey of variable stars in the Draco dwarf spheroidal galaxy updates the pioneering study of this galaxy by Baade and Swope (1961). Our improved data, taken in BVI filters with CCD cameras on three telescopes at more than 80 epochs, allow us to investigate the known variables and to discover new, mostly low-amplitude variables. Tentative identification and classification of variables cowering nearly the entire galaxy finds a total of 290 variable stars that are likely members of Draco (209 RRab stars, 28 RRc stars, 29 double-made RR. Lyraes, 10 Anomalous Cepheids, 11 red semi-regulars, and 3 miscellaneous variables) and 25 probable field variables (mostly probable QSOs). Of the RRab stars, 27 are probably Blazhko variables. This large sample of variables provides a unique opportunity to study the properties of these stars in a single system. C1 USN Observ, Flagstaff, AZ 86002 USA. RP Harris, HC (reprint author), USN Observ, Flagstaff, AZ 86002 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-55-4 J9 ASTR SOC P PY 1998 VL 135 BP 164 EP 168 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BK82C UT WOS:000073481200041 ER PT B AU Henden, AA Stone, RC AF Henden, AA Stone, RC BE Bradley, PA Guzik, JA TI Variable stars in the SDSS calibration fields SO HALF CENTURY OF STELLAR PULSATION INTERPRETATIONS: A TRIBUTE TO ARTHUR N. COX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on a Half Century of Stellar Pulsation Interpretations CY JUN 16-20, 1997 CL LOS ALAMOS, NM C1 USN Observ, Flagstaff Stn, Flagstaff, AZ USA. RP Henden, AA (reprint author), USN Observ, Flagstaff Stn, Flagstaff, AZ USA. 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 USA BN 1-886733-55-4 J9 ASTR SOC P PY 1998 VL 135 BP 364 EP 365 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BK82C UT WOS:000073481200098 ER PT J AU De Long, HC Mitchell, JA Trulove, PC AF De Long, HC Mitchell, JA Trulove, PC TI Investigations of the electrodeposition of aluminum-manganese alloys from room temperature chloroaluminate molten salts SO HIGH TEMPERATURE MATERIAL PROCESSES LA English DT Article DE electrodeposition; molten salts; EQCM; aluminum and magnesium ID CORROSION; PHASE AB The electrochemical reduction of manganese (II) in acidic AlCl3:EMIC (aluminum chloride:1-ethyl-3-methylimidazolium chloride) room temperature molten salt results in codeposition of aluminum and manganese. Constant potential deposition in the region of the reduction peak results in the deposition of manganese rich amorphous manganese-aluminum alloys. Constant potential deposition in the region of diffusion control results in the formation of aluminum rich amorphous manganese-aluminum alloys. We have employed an Electrochemical Quartz Crystal Microbalance (EQCM) to investigate, in situ, the deposition and stripping behavior of Al and AI-M-x in acidic AlCl3:EMIC molten salts. The EQCM provides both mass and charge data during electrodeposition and stripping processes. This information can be used to determine codeposited metal composition and to model deposition and/or stripping processes. C1 USAF, Off Sci Res, Washington, DC 20332 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP De Long, HC (reprint author), USAF, Off Sci Res, Bolling AFB, Washington, DC 20332 USA. NR 19 TC 10 Z9 11 U1 1 U2 8 PU BEGELL HOUSE INC PI NEW YORK PA 79 MADISON AVE, SUITE 1205, NEW YORK, NY 10016-7892 USA SN 1093-3611 J9 HIGH TEMP MATER P-US JI High Temp. Mater. Process PY 1998 VL 2 IS 4 BP 507 EP 519 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA 177TA UT WOS:000079226100007 ER PT J AU Cho, TH Fuller, J Carlin, RT AF Cho, TH Fuller, J Carlin, RT TI Catalytic hydrogenation using supported ionic liquid membranes SO HIGH TEMPERATURE MATERIAL PROCESSES LA English DT Article ID CHLOROALUMINATE MOLTEN-SALT; RHODIUM COMPLEXES; KINETICS; AIR AB Supported ionic liquid membranes (SILMs) were employed to examine the homogeneous catalytic hydrogenation of propane and ethene. In these membranes, room-temperature imidazolium perfluoroanion ionic liquids served as solvents for the homogeneous catalyst Rh(nbd)(PPh3)(2)(+) (nbd = norbornadiene). The membranes were fabricated by supporting various ionic liquids, each containing 16 - 23 mM of the Rh(I) complex, in the pores of poly(vinylidene fluoride) filter membranes. During operation, the olefin was maintained at 1 atm on the feed side of the membrane, while 1 atm of hydrogen gas was swept over the permeate side and sent through a sampling loop for continuous real-time analysis. In this SILM configuration, hydrogenation of the olefin to the corresponding alkane took place as the olefin diffused through the ionic liquid region of the composite membrane structure. Rates of hydrogenation were determined as a function of the ionic liquid solvent and of total run time - the latter data providing information on the stability of the homogeneous catalyst. Maximum rates of propene hydrogenation to propane in the different ionic liquid solvents followed the order EMI(imide) > EMI(triflate) > EMIBF4 > BMTPF6 approximate to DMPIBF4. Ethene hydrogenation rates followed a similar trend. Gas permeability coefficients were used to estimated olefin solubilities in each of the ionic liquids. The solubility ordering for both gases was DMPIBF4 > BMIPF6 > EMI(imide) > EMI(triflate) > EMIBF4. The influence of the coordinating ability of the ionic liquid perfluoroanions on reaction rates and solubilities is discussed, and a selective distribution of the catalyst and olefin within the ionic liquid structure is postulated. C1 Worcester Acad, Dept Chem, Worcester, MA 01604 USA. SAF AQRT, Washington, DC 20330 USA. Off Naval Res, Arlington, VA 22217 USA. RP Cho, TH (reprint author), Worcester Acad, Dept Chem, 81 Providence St, Worcester, MA 01604 USA. NR 33 TC 22 Z9 22 U1 2 U2 6 PU BEGELL HOUSE INC PI NEW YORK PA 79 MADISON AVE, SUITE 1205, NEW YORK, NY 10016-7892 USA SN 1093-3611 J9 HIGH TEMP MATER P-US JI High Temp. Mater. Process PY 1998 VL 2 IS 4 BP 543 EP 558 PG 16 WC Materials Science, Multidisciplinary SC Materials Science GA 177TA UT WOS:000079226100009 ER PT S AU Ebisawa, K Takeshima, T White, NE Kotani, T Dotani, T Ueda, Y Harmon, BA Robinson, CR Zhang, SN Paciesas, WS Tavani, M Foster, R AF Ebisawa, K Takeshima, T White, NE Kotani, T Dotani, T Ueda, Y Harmon, BA Robinson, CR Zhang, SN Paciesas, WS Tavani, M Foster, R BE Koyama, K Kitamoto, S Itoh, M TI ASCA observations of the superluminal jet source GRS1915+105 SO HOT UNIVERSE SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 188th Symposium of the International-Astronomical-Union - The Hot Universe CY AUG 26-30, 1997 CL KYOTO, JAPAN SP Int Astron Union C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RIKEN, Inst Phys & Chem Res, Wako, Saitama 35101, Japan. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 229, Japan. NASA, George Marshall Space Flight Ctr, Huntsville, AL 35806 USA. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. USN, Res Lab, Washington, DC 20375 USA. RP Ebisawa, K (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 661, Greenbelt, MD 20771 USA. RI White, Nicholas/B-6428-2012 OI White, Nicholas/0000-0003-3853-3462 NR 0 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0074-1809 BN 0-7923-5058-8 J9 IAU SYMP PY 1998 IS 188 BP 392 EP 393 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BM04D UT WOS:000077472500139 ER PT J AU McKeown, MJ Makeig, S Brown, GG Jung, TP Kindermann, SS Bell, AJ Sejnowski, TJ AF McKeown, MJ Makeig, S Brown, GG Jung, TP Kindermann, SS Bell, AJ Sejnowski, TJ TI Analysis of fMRI data by blind separation into independent spatial components SO HUMAN BRAIN MAPPING LA English DT Article DE functional magnetic resonance imaging; independent component analysis; higher-order statistics ID HUMAN BRAIN; SENSORY STIMULATION; ALGORITHM; AGRAPHIA; ALEXIA AB Current analytical techniques applied to functional magnetic resonance imaging (fMRI) data require a priori knowledge or specific assumptions about the time courses of processes contributing to the measured signals. Here we describe a new method for analyzing fMRI data based on the independent component analysis (ICA) algorithm of Bell and Sejnowski ([1995]: Neural Comput 7:1129-1159). We decomposed eight fMRI data sets from 4 normal subjects performing Stroop color-naming, the Brown and Peterson word/number task, and control tasks into spatially independent components. Each component consisted of voxel values at fixed three-dimensional locations (a component "map"), and a unique associated time course of activation. Given data from 144 time points collected during a 6-min trial, ICA extracted an equal number of spatially independent components. In all eight trials, ICA derived one and only one component with a time course closely matching the time course of 40-sec alternations between experimental and control tasks. The regions of maximum activity in these consistently task-related components generally overlapped active regions detected by standard correlational analysis, but included frontal regions not detected by correlation. Time courses of other ICA components were transiently task-related, quasiperiodic, or slowly varying. By utilizing higher-order statistics to enforce successively stricter criteria for spatial independence between component maps, both the ICA algorithm and a related fourth-order decomposition technique (Comon [1994]: Signal Processing 36:11-20) were superior to principal component analysis (PCA) in determining the spatial and temporal extent of task-related activation. For each subject, the time courses and active regions of the task-related ICA components were consistent across trials and were robust to the addition of simulated noise. Simulated movement artifact and simulated task-related activations added to actual fMRI data were clearly separated by the algorithm. ICA can be used to distinguish between nontask-related signal components, movements, and other artifacts, as well as consistently or transiently task-related fMRI activations, based on only weak assumptions about their spatial distributions and without a priori assumptions about their time courses. ICA appears to be a highly promising method for the analysis of fMRI data from normal and clinical populations, especially for uncovering unpredictable transient patterns of brain activity associated with performance of psychomotor tasks. (C) 1998 Wiley-Liss, Inc. C1 Salk Inst Biol Studies, Howard Hughes Med Inst, Computat Neurobiol Lab, San Diego, CA 92186 USA. USN, Hlth Res Ctr, Cognit Pyschophysiol Lab, San Diego, CA 92186 USA. Univ Calif San Diego, Sch Med, Dept Neurosci, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Biol, La Jolla, CA 92093 USA. Univ Calif San Diego, Sch Med, Dept Psychiat, La Jolla, CA 92093 USA. RP McKeown, MJ (reprint author), Salk Inst Biol Studies, Computat Neurobiol Lab, 10010 N Torrey Pines Rd, La Jolla, CA 92037 USA. NR 42 TC 1093 Z9 1139 U1 6 U2 62 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1065-9471 J9 HUM BRAIN MAPP JI Hum. Brain Mapp. PY 1998 VL 6 IS 3 BP 160 EP 188 DI 10.1002/(SICI)1097-0193(1998)6:3<160::AID-HBM5>3.0.CO;2-1 PG 29 WC Neurosciences; Neuroimaging; Radiology, Nuclear Medicine & Medical Imaging SC Neurosciences & Neurology; Radiology, Nuclear Medicine & Medical Imaging GA ZQ918 UT WOS:000073916100005 PM 9673671 ER PT J AU Kass, SJ Ahlers, RH Dugger, M AF Kass, SJ Ahlers, RH Dugger, M TI Eliminating gender differences through practice in an applied visual spatial task SO HUMAN PERFORMANCE LA English DT Article ID MENTAL ROTATION; SEX-DIFFERENCES; PERFORMANCE-FACTORS; ABILITY AB Training strategies to reduce the well-documented (e.g., Linn & Petersen, 1985; Voyer, Voyer, & Bryden, 1995) gender difference in visual spatial ability were investigated. Participants (21 men, 21 women) were trained under 1 of 2 conditions to estimate the orientation angle of a ship viewed on a submarine periscope simulator. The data were analyzed in a 3 x 2 x 2 (Training Conditions x Gender x Test Session) mixed design with repeated measures over the last variable. A significant Training Condition x Gender interaction revealed large performance differences in favor of men in the control group and the group trained using an instruction manual. However, no significant gender difference was found for participants trained with repeated practice accompanied by feedback. This suggests that even a brief training session, using an appropriate instructional strategy, may be all that is required to increase the mental rotation performance of women to the level of men on a specific task. The benefit of the instruction was still evident when tested 3 weeks later; the gender difference was still absent. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. Stetson Univ, Dept Psychol, De Land, FL USA. RP Ahlers, RH (reprint author), USN, Air Warfare Ctr, Training Syst Div, Code 4961,12350 Res Pkwy, Orlando, FL 32826 USA. NR 29 TC 40 Z9 40 U1 2 U2 11 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0895-9285 J9 HUM PERFORM JI Hum. Perform. PY 1998 VL 11 IS 4 BP 337 EP 349 DI 10.1207/s15327043hup1104_3 PG 13 WC Psychology, Applied SC Psychology GA 121UL UT WOS:000076032400003 ER PT S AU von Berg, DCL AF von Berg, DCL BE Casasent, DP Tescher, AG TI Interaction of on-board transform-based lossy compression algorithms with EO/IR focal plane nonuniformity correction techniques SO HYBRID IMAGE AND SIGNAL PROCESSING VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Hybrid Image and Signal Processing VI CY APR 16, 1998 CL ORLANDO, FL SP SPIE DE compression; nonuniformity correction; pre-processing; EO/IR; image quality AB This paper describes the effect of using lossy transform-based compression on infrared framing sensor data with and without sensor anomaly pre-processing. Significant image degradation persists when ground-based non-uniformity correction processing is implemented after the sensor imagery has been compressed and reconstructed. Various techniques for nonuniformity correction, from low to high processing complexity (i.e., standard two-point gain/offset correction, two-point with bad-pixel replacement, adaptive temporal high pass filtering, adaptive neural net non-uniformity correction, etc.), are applied before and after lossy compression at varying compression ratios. Results using both DCT and Wavelet transform-based compression techniques indicate that on-board real-time compression algorithms and nonuniformity correction must be jointly optimized and that direct application of lossy compression without preprocessing for sensor anomalies reduces not only the compression efficiency and image fidelity, but also the performance of subsequent ground-based nonuniformity correction. C1 USN, Res Lab, Washington, DC 20375 USA. RP von Berg, DCL (reprint author), USN, Res Lab, Code 5636,4555 Overlook Ave, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2838-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3389 BP 2 EP 13 DI 10.1117/12.316529 PG 12 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BL57L UT WOS:000075914900001 ER PT B AU Ly, LN AF Ly, LN BE Blain, WR TI A numerical simulation of summer circulation for Monterey Bay SO HYDRAULIC ENGINEERING SOFTWARE VII SE COMPUTATIONAL METHODS IN WATER RESOURCES LA English DT Proceedings Paper CT 7th International Conference on Hydraulic Engineering Software (Hydrosoft 98) CY SEP, 1998 CL VILLA OLMO, ITALY SP Wessex Inst Technol, Ctr Cultura Sci Alessandro Volta ID MODEL AB A three dimensional coastal ocean system for Monterey Bay (MOB) is developed using numerical grid generation to study the summer circulation. The system is a primitive equation coastal ocean modeling system, which consists of a coastal ocean model, numerical grid generation routines, and a grid package which allows the model to be coupled to model grids. In this coastal ocean system, a curvilinear nearly-orthogonal (CNO) grid is used to enhance the model numerical solution. The MOB model has 28 sigma vertical levels, and the CNO coastline-following numerical grid has 131 x 131 grid points, which cover a domain of 150 km by 150 km. The model has horizontal resolutions of 200 m to 2 km, free surface dynamics, and realistic coastlines and bottom bathymetry. The model code is written for a multi-block grid, but a single-block CNO grid is demonstrated for the MOB simulations, The MOB model and the associated grid are used to simulate summer circulation and reproduce the MOB basic physics such as coastal currents and upwelling locations. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Ly, LN (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU COMPUTATIONAL MECHANICS PUBLICATIONS LTD PI SOUTHAMPTON PA ASHURST LODGE, SOUTHAMPTON S04 2AA, HANTS, ENGLAND BN 1-85312-599-7 J9 COMP MET WATER RES PY 1998 VL 4 BP 269 EP 277 PG 9 WC Engineering, Environmental; Engineering, Civil; Engineering, Mechanical; Water Resources SC Engineering; Water Resources GA BM74J UT WOS:000079666600026 ER PT S AU Gao, BC Davis, CO AF Gao, BC Davis, CO BE Green, RO Tong, Q TI Examples of using imaging spectrometry for remote sensing of the atmosphere, land, and ocean SO HYPERSPECTRAL REMOTE SENSING AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Hyperspectral Remote Sensing and Application CY SEP 15-16, 1998 CL BEIJING, PEOPLES R CHINA SP SPIE Int Soc Opt Engn, Natl Ctr Atmospher Res, Atmospher Chem Div (USA), Chinese Acad Sci, Inst Atmospher Physics, CSSR, Chinese Soc Space Res, COEMA DE imaging spectrometer; atmospheric correction; hyperspectral imaging; ocean color; aerosol AB The concept of imaging spectrometry was originated from geological communities in the early 1980's. The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) built at NASA Jet Propulsion Laboratory has been collecting spectral imaging data in the 0.4 - 2.5 micron region from an ER-2 aircraft at 20 km for a decade. Newer generations of airborne and spaceborne imaging spectrometers have also been built. In this paper, techniques, such as spectral matching and channel ratioing for extracting information on the Earth's atmosphere and surfaces are illustrated. Examples of using the technique of imaging spectrometry for remote sensing of atmospheric water vapor! cirrus clouds, aerosols, fire, land surface properties, and ocean color are presented. The applications of imaging spectrometry to the selection and implementation of new channels on the Moderate Resolution Imaging Spectroradiometer (MODIS) for global remote sensing of atmospheric water vapor and cirrus clouds from space are also described. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Gao, BC (reprint author), USN, Res Lab, Remote Sensing Div, Code 7212,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2961-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3502 BP 234 EP 242 DI 10.1117/12.317810 PG 9 WC Remote Sensing SC Remote Sensing GA BL83R UT WOS:000076893800031 ER PT J AU Kennedy, TA Glaser, ER AF Kennedy, TA Glaser, ER TI Magnetic resonance of epitaxial layers detected by photoluminescence SO IDENTIFICATION OF DEFECTS IN SEMICONDUCTORS SE SEMICONDUCTORS AND SEMIMETALS LA English DT Article ID NUCLEAR DOUBLE-RESONANCE; MOLECULAR-BEAM EPITAXY; OPTICAL-DETECTION; SHALLOW ACCEPTOR; SINGLE-MOLECULE; POINT-DEFECTS; ZNSE-N; ALXGA1-XAS; DONOR; RECOMBINATION C1 USN, Res Lab, Washington, DC 20375 USA. RP Kennedy, TA (reprint author), USN, Res Lab, Code 6877, Washington, DC 20375 USA. NR 71 TC 12 Z9 12 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0080-8784 J9 SEMICONDUCT SEMIMET PY 1998 VL 51 BP 93 EP 136 PN A PG 44 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BM64A UT WOS:000079321800003 ER PT S AU Darken, RP Banker, WP AF Darken, RP Banker, WP GP IEEE COMP SOC TI Navigating in natural environments: A virtual environment training transfer study SO IEEE 1998 VIRTUAL REALITY ANNUAL INTERNATIONAL SYMPOSIUM, PROCEEDINGS SE PROCEEDINGS OF THE IEEE VIRTUAL REALITY ANNUAL INTERNATIONAL SYMPOSIUM LA English DT Proceedings Paper CT IEEE 1998 Virtual Reality Annual International Symposium CY MAR 14-18, 1998 CL ATLANTA, GA SP IEEE Comp Soc, Tech Comm Comp Graph, IEEE Neural Networks Council Virtual Real Tech Comm AB The ability to use virtual environments as either an abstraction of a space, similar to a map, or as a simulation of the space itself has suggested to many that it would be a useful tool in terrain familiarization of unknown environments. To this point, all research in this area has focused on building interiors and urban environments which are significantly different from natural environments in terms of navigation cues and useful way finding techniques. The experiment we present uses a virtual environment as compared to a map only or real world condition on navigation tasks in a natural environment. We show that navigation ability is more important to performance than training method with the virtual environment being most effective for intermediate orienteers as compared to advanced or beginner orienteers. C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. RP Darken, RP (reprint author), USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. NR 0 TC 27 Z9 27 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1087-8270 BN 0-7803-4782-X J9 P IEEE VIRT REAL ANN PY 1998 BP 12 EP 19 DI 10.1109/VRAIS.1998.658417 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Software Engineering SC Computer Science GA BK52S UT WOS:000072438600003 ER PT S AU Watsen, K Zyda, M AF Watsen, K Zyda, M GP IEEE COMP SOC TI Bamboo - Portable system for dynamically extensible, real-time, networked, virtual environments SO IEEE 1998 VIRTUAL REALITY ANNUAL INTERNATIONAL SYMPOSIUM, PROCEEDINGS SE PROCEEDINGS OF THE IEEE VIRTUAL REALITY ANNUAL INTERNATIONAL SYMPOSIUM LA English DT Proceedings Paper CT IEEE 1998 Virtual Reality Annual International Symposium CY MAR 14-18, 1998 CL ATLANTA, GA SP IEEE Comp Soc, Tech Comm Comp Graph, IEEE Neural Networks Council Virtual Real Tech Comm DE portable; multi-platform; dynamically-extensible; realtime; networking; virtual environment; virtual reality; toolkit; framework; system AB Bamboo is a portable system supporting real-time, networked, virtual environments. Unlike previous efforts, this design focuses on the ability for the system to dynamically configure itself without explicit user interaction, allowing applications to take on new functionality after execution. In particular, this framework facilitates the discovery of virtual environments on the network at runtime. Fundamentally, Bamboo offers a compatible set of mechanisms needed for a wide variety of real-time, networked applications. Also included is a particular combination of these mechanisms supporting dynamically extensible runtime environment. This paper serves as a general introduction to Bamboo. It describes the system's architecture, implementation, and future directions. It also shows how the system can facilitate the rapid development of robust applications by promoting code reuse via communitywide exchange. C1 USN, Postgrad Sch, Monterey, CA 93940 USA. RP Watsen, K (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 0 TC 19 Z9 19 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1087-8270 BN 0-7803-4782-X J9 P IEEE VIRT REAL ANN PY 1998 BP 252 EP 259 DI 10.1109/VRAIS.1998.658503 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Software Engineering SC Computer Science GA BK52S UT WOS:000072438600042 ER PT B AU Nedlin, GM Chubb, SR Cooper, AL AF Nedlin, GM Chubb, SR Cooper, AL GP IEEE TI Integral equation method for electromagnetic scattering from the ocean. SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USN, Res Lab, Div Remote Sensing, Washington, DC 20375 USA. RP Nedlin, GM (reprint author), USN, Res Lab, Div Remote Sensing, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 88 EP 91 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900024 ER PT B AU Jenn, DC Pace, PE Hatziathanasiou, T Vitale, R AF Jenn, DC Pace, PE Hatziathanasiou, T Vitale, R GP IEEE TI Symmetrical number system phase sampled DF antenna architectures SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USN, Ctr Joint Serv Elect Warfare, Postgrad Sch, Monterey, CA 93943 USA. RP Jenn, DC (reprint author), USN, Ctr Joint Serv Elect Warfare, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 199 EP 202 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900051 ER PT B AU Roan, GT Zaki, KA AF Roan, GT Zaki, KA GP IEEE TI Application of the FDTD method to the analysis of biconical antennas SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USN, Res Lab, Washington, DC 20375 USA. RP Roan, GT (reprint author), USN, Res Lab, Code 5713, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 516 EP 519 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900126 ER PT J AU Baggenstoss, PM AF Baggenstoss, PM TI Adaptive pulselength correction (APLECORR): A strategy for waveform optimization in ultrawideband active sonar SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE dispersive channels; fading channels; scatter channels; signal design; sonar detection; sonar scattering; sonar signal processing; time-varying channels AB This paper describes adaptive pulselength correction (APLECORR), an environmentally adaptive technique for optimizing the detection performance in wide-band active sonars in so-called doubly spread channels, It works by allocating available transmit energy to frequency bands according to the in situ measured reverberation and ambient noise spectra, It optimizes the waveform and the detection processor at the same time, It is appealing in its simplicity and achieves significant gains whenever the reverberation-to-noise ratio is not constant across frequency, thus its applicability to wide-band systems, The method extends easily to PRN and other non-FM waveforms, The paper includes a proof that time-spreading and frequency-spreading distortion have an approximately equivalent effect if the waveform is linear or hyperbolic frequency modulation. C1 USN, Undersea Warfare Ctr, Newport, RI 02840 USA. RP Baggenstoss, PM (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02840 USA. NR 9 TC 14 Z9 14 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JAN PY 1998 VL 23 IS 1 BP 1 EP 11 DI 10.1109/48.659444 PG 11 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA YX953 UT WOS:000072097200001 ER PT J AU Fabrikant, AL Spiesberger, JL Silivra, AA Hurlburt, HE AF Fabrikant, AL Spiesberger, JL Silivra, AA Hurlburt, HE TI Estimating climatic temperature change in the ocean with synthetic acoustic apertures SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE acoustic tomography; climate change; Kalman filtering; synthetic aperture imaging ID TOMOGRAPHY; MODELS AB An acoustic tomography simulation is carried out in the eastern North Pacific ocean to assess whether climate trends are better detected and mapped with mobile or fixed receivers, In both cases, acoustic signals from two stationary sources are transmitted to ten receivers, Natural variability of the sound-speed field is simulated with the Naval Research Laboratory (NRL) layered-ocean model, A sequential Kalman-Bucy filter is used to estimate the sound speed field, where the apriori error covariance matrix of the parameters is estimated from the NRL model, A spatially homogeneous climate trend is added to the NRL fluctuations of sound speed, but the trend is not parameterized in the Kalman filter, Acoustic travel times are computed between the sources and receivers by combining sound speeds from the NRL model with those from the unparameterized climate trend, The effects of the unparameterized climate trend are projected onto parameters which eventually drift beyond acceptable limits, At that time, the unparameterized trend is detected, Mobile and fixed receivers detect the trend at about the same time, At detection time, however, maps from fixed receivers are less accurate because some of the unparameterized climate trend is projected onto the spatially-varying harmonics of the sound-speed field, With mobile receivers, the synthetic apertures suppress the projection onto these harmonics, Instead, the unparameterized trend is correctly projected onto the spatially homogeneous portion of the parameterized sound speed field. C1 Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Penn State Univ, Appl Res Lab, University Pk, PA 16802 USA. Penn State Univ, Appl Res Lab, State Coll, PA 16804 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Fabrikant, AL (reprint author), Thermawave Inc, Fremont, CA 94539 USA. NR 24 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JAN PY 1998 VL 23 IS 1 BP 20 EP 25 DI 10.1109/48.659446 PG 6 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA YX953 UT WOS:000072097200003 ER PT J AU Vurgaftman, I Meyer, JR Ram-Mohan, LR AF Vurgaftman, I Meyer, JR Ram-Mohan, LR TI Mid-IR vertical-cavity surface-emitting lasers SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE cavity resonators; CW lasers; quantum-well lasers; semiconductor device modeling; semiconductor lasers; surface-emitting lasers ID DISTRIBUTED BRAGG REFLECTORS; CONTINUOUS-WAVE OPERATION; ROOM-TEMPERATURE; SEMICONDUCTOR-LASERS; 2-DIMENSIONAL ARRAYS; CASCADE LASERS; PERFORMANCE; MIRRORS; DESIGN; FABRICATION AB We theoretically investigate the feasibility and potential performance of optically and electrically pumped vertical-cavity surface-emitting lasers (VCSEL's) emitting in the mid-IR spectral region, Our model includes spontaneous, stimulated, and nonradiative recombination, numerical dispersion relations and optical matrix elements from a multiband finite-element algorithm, carrier and lattice heating, three-dimensional heat flow, electrical injection, photon propagation, and diffraction, Each modeled structure consists of a distributed Bragg reflector (DBR) semiconductor bottom mirror, a lambda, 2 lambda, or 3 lambda optical cavity incorporating the type-II active region, a dielectric top mirror through which the output is emitted. The optically pumped VCSEL structure with a 10-mu m-diameter spot is predicted to operate up to a heat-sink temperature of 250 K and to be capable of producing >2 mW of CW output power, Furthermore, by collimating the pump beam with a microlens array, gain-guided VCSEL arrays with output powers in the watt range should be attainable, Comparable powers and operating temperatures are predicted for patterned devices with electrical injection through annular contacts, By far the most attractive properties are expected for structures employing a type-II interband cascade active region with electron recycling. The simulation predicts single-element threshold currents of 150 mu A at 200 K and 1.1 mA at 300 K and CW output powers of 4.7 and 1.2 mW, respectively. C1 USN, Res Lab, Washington, DC 20375 USA. Worcester Polytech Inst, Worcester, MA 01609 USA. RP Vurgaftman, I (reprint author), USN, Res Lab, Code 5613, Washington, DC 20375 USA. RI Ram-Mohan, Ramdas/C-5167-2012 NR 45 TC 31 Z9 31 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD JAN PY 1998 VL 34 IS 1 BP 147 EP 156 DI 10.1109/3.655018 PG 10 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA YP054 UT WOS:000071236600019 ER PT J AU Murata, H Merritt, CD Kafafi, ZH AF Murata, H Merritt, CD Kafafi, ZH TI Emission mechanism in rubrene-doped molecular organic light-emitting diodes: Direct carrier recombination at luminescent centers SO IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS LA English DT Article DE direct carrier recombination; emission mechanism; energy transfer; organic light-emitting diodes; rubrene ID HOLE TRANSPORT AB The emission mechanism in molecularly doped organic light-emitting diodes, where the emitting layer is composed of N,N'-diphenyl-N,N' -bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD) as the host and 5,6,11,12-tetraphenylnapthacene (rubrene) as the dopant, is investigated in terms of energy transfer and direct carrier recombination, Hole trapping by rubrene is identified by current versus voltage and mobility measurements in single layered devices. Shallow traps are formed and are found to be filled by injected holes at electric field above 2 x 10(5) V/cm, Electroluminescence observed in single-layered devices indicate that electrons can be injected directly into the hole transporter, TPD, In double-layered devices composed of TPD and tris-(8-hydroxyquinolinato) aluminum(III) (Alq(3)), the penetration depth of electrons into undoped TPD is determined to be less than or equal to 5 nm from the Alq(3) interface. Upon doping with rubrene, the emission zone is extended to 20 nm due to the increase in the electron penetration depth. This is attributed to the transition of the electron hopping sites from TPD to rubrene molecules. At high-rubrene concentration, electron transport occurs via hopping on the rubrene molecules. The dominant emission mechanism in rubrene-doped TPD is attributed to the electron-hole recombination at the dopant molecule. This is maximized by hole trapping and electron transport of rubrene. C1 SFA Inc, Largo, MD 20774 USA. USN, Res Lab, Washington, DC 20375 USA. RP Murata, H (reprint author), SFA Inc, Largo, MD 20774 USA. RI Murata, Hideyuki/J-8453-2012 OI Murata, Hideyuki/0000-0001-8248-9652 NR 15 TC 149 Z9 158 U1 3 U2 17 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1077-260X J9 IEEE J SEL TOP QUANT JI IEEE J. Sel. Top. Quantum Electron. PD JAN-FEB PY 1998 VL 4 IS 1 BP 119 EP 124 DI 10.1109/2944.669481 PG 6 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZM117 UT WOS:000073506400015 ER PT S AU Park, VD Macker, JP Corson, MS AF Park, VD Macker, JP Corson, MS GP IEEE IEEE TI Applicability of the temporally-ordered routing algorithm for use in mobile tactical networks SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB In this payer we present a conceptual overview of the Temporally-Ordered Routing Algorithm (TORA), discuss the philosophy that shaped its design and consider its applicability Sor use in forward-deployed mobile tactical networks. The salient characteristics of mobile, multihop, wireless networks differ significantly from those of traditional hardwired networks. Consequently, the routing protocols that have been designed for operation in the Internet are not particularly well-suited for use in mobile tactical environments. TORA, which has been tailored for operation in this highly-dynamic networking environment, represents a significant departure from the traditional "shortest-path" routing paradigm. We also highlight recent simulation results of a performance comparison with ideal Link-State (ILS) routing. The results show that the relative performance of TORA and ILS is critically dependent on the network size and average rare of topological changes. The results further indicate that the performance of TORA exceeds that of ILS for the conditions expected in relatively large mobile networks, lending credence to the philosophy behind the TORA design. C1 USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. RP Park, VD (reprint author), USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 426 EP 430 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600078 ER PT S AU Tedesso, TW Robertson, RC AF Tedesso, TW Robertson, RC GP IEEE IEEE TI Performance analysis of a SFH/NCBFSK communication system with rate 1/2 convolutional coding in the presence of partial-band noise jamming SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB A performance analysis of a slow frequency-hopped, noncoherent binary frequency-shift keying (SFH/NCBFSK) communication system with rate 1/2 convolutional coding and soft decision Viterbi decoding in the presence of partial-band noise jamming is performed. The effect of additive white Gaussian noise is also considered. The system's performance is severely degraded by partial-band noise jamming. By way of comparison, a system that utilizes hard decision Viterbi decoding and for a system utilizing noise-normalized combining with soft decision Viterbi decoding are examined. In both cases a significant increase in the system's immunity to the effects of partial-band noise jamming is achieved. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Tedesso, TW (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Code EC-Rc, Monterey, CA 93943 USA. EM crobertson@nps.navy.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 484 EP 488 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600089 ER PT S AU Lundy, GM Almquist, M Oruk, T AF Lundy, GM Almquist, M Oruk, T GP IEEE IEEE TI Specification, verification and simulation of a wireless lan protocol: MACAW SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB A formal specification and verification of a wireless LAN protocol is given, and a simulation of the protocol's performance is also described. The verification is a partial verification in that it does not include a general verification of all possible configurations of the protocol; however, it does cover the expected usage of the protocol, which is for a small number of users sharing a cell. The simulation provides further insight into the protocol, especially concerning its performance. Based on the verification and simulation, some suggestions are made which can improve the protocol's performance. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Lundy, GM (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 565 EP 569 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600105 ER PT S AU Macker, J Park, V AF Macker, J Park, V GP IEEE IEEE TI Internetwork traffic management enhancements: Evaluation and experimental results SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB In recent years, there has been an increasing reliance on internetworking technology for military communication networks. As more diverse and mission critical applications begin to coexist within this shared infrastructure the need for improved network traffic and bandwidth management becomes apparent. Recent developments within the research community and within commercial products provide numerous candidate technologies that may be applied as solutions. This paper explores a set of such techniques while evaluating their relative merits and performance tradeoffs. A subset of empirical results from an actual testbed environment is also provided and discussed. C1 Naval Res Lab, Div Informat Technol, Washington, DC 20375 USA. RP Macker, J (reprint author), Naval Res Lab, Div Informat Technol, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 609 EP 613 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600113 ER PT S AU Wieselthier, JE Nguyen, GD Ephremides, A AF Wieselthier, JE Nguyen, GD Ephremides, A GP IEEE IEEE TI Multicasting in energy-limited ad-hoc wireless networks SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB In this paper, we address the problem of multicasting in military "ad-hoc" wireless networks. Since such networks lack a fixed cellular infrastructure, multicast algorithms that are based on the availability of fixed, known topologies cannot be used effectively. Even when the locations of the nodes rare fixed and known, the properties of the wireless medium create a networking environment that is vastly different from that Of wired networks, and for which the multicasting problem has scarcely been addressed. Specifically, the broadcast mature of wireless transmission and the dependence of range on transmission power create new opportunities for multicasting that need to be traded off against the interference caused by such transmissions. We address the ways in which wireless network characteristics, as well as the constraints of limited energy, affect multicast protocol operation, preliminary trade-offs are provided and future research directions are outlined. C1 USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. RP Wieselthier, JE (reprint author), USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. EM wieselthier@itd.nrl.navy.mil; nguyen@itd.nrl.navy.mil; tony@eng.umd.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 723 EP 729 PG 7 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600135 ER PT S AU Welch, TB Ziemer, RE AF Welch, TB Ziemer, RE GP IEEE IEEE TI Analysis of MC-DS-CDMA systems in doubly spread channels SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB Kondo and Milstein introduced and analyzed the performance of a system that combined multicarrier modulation (MCM) with direct-sequence spread spectrum (DSSS) in late 1993. Their system and similar systems are called MC-DS-CDMA systems [1]. The dramatic performance improvement of this system (as compared to a single carrier system operating in a flat fading channel) is due, in part, to the use of coherent modulation/demodulation and perfect knowledge of the complex channel gains for each of the independent channels associated with every subcarrier. In this paper we investigate the performance degradation associated with a more easily realized system. Our system employs differentially coherent modulation/demodulation with an equal gain combiner (EGC) at the receiver. We investigate the performance of this system operating in a doubly spread (Doppler and delay spread) channel. In a doubly spread channel, any system which does not account for the rapid variations in channel phase will exhibit an irreducible bit error probability. This phenomenon exists even for the single user case. A system utilizing an EGC is analyzed for the single user case and in the presence of multiple access interference (MAI). The MC-DS-CDMA single user system, with E(b)/N(0) = 18.5 dB, can achieve a BEP of 10(-6) in a doubly spread channel (f(d)T = 0.08 and a channel delay spread, tau(0) = 1 mu s), while a single carrier DPSK system operating at the same E(b)/N(0) and under the same channel conditions would achieve a BEP of 0.037. The multi-user system with 50 active users would achieve a BEP of 0.008 as compared to a BEP of 0.07 for a single carrier system. C1 USN Acad, Annapolis, MD 21402 USA. RP Welch, TB (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 757 EP 761 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600141 ER PT S AU Victory, CW Ha, TT AF Victory, CW Ha, TT GP IEEE IEEE TI Performance analysis of direct sequence differential phase shift keying (DS-DPSK) with self-normalization and L-fold diversity in a fading channel SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB The performance of a Direct Sequence Differential Phase Shift Keying (DS-DPSK) spread spectrum system employing time diversity and self-normalization over a Rician frequency nonselective, slowly fading channel in the presence of pulsed noise interference and additive white Gaussian noise (AWGN) is considered. An interference model which considers the possibility chat either both, one or none of the information bits experience jamming is employed Worst case performance under severe and moderate fading conditions are analyzed Results indicate that the self-normalized receiver is effective in mitigating the effects of pulse noise jamming for all fading conditions considered. C1 USN, Postgrad Sch, Dept ECE, Monterey, CA 93943 USA. RP Victory, CW (reprint author), USN, Postgrad Sch, Dept ECE, Code ECHA, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 862 EP 866 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600162 ER PT S AU Kruus, PS Macker, JP AF Kruus, PS Macker, JP GP IEEE IEEE TI Techniques and issues in multicast security SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB Multicast networking support is becoming an increasingly important future technology area for both commercial and military distributed and group-based applications. Integrating a multicast security solution involves numerous engineering tradeoff The end goal of effective operational performance and scalability over a heterogeneous internetwork is of primary interest for widescale adoption and application of such a capability. Various techniques that have been proposed to support multicast security are discussed and their relative merits are explored. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kruus, PS (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM kruus@itd.nrl.navy.mil; macker@itd.nrl.navy.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 1028 EP 1032 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600193 ER PT S AU Krout, T Solsman, M Goldstein, J AF Krout, T Solsman, M Goldstein, J GP IEEE IEEE TI The effects of asymmetric satellite networks on protocols SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB The Naval Research Laboratory (NRL) is conducting a simulation and experimental effort to document and optimize the use of Internet Protocol (IP) over satellite based highly asymmetric networks. Within the DoD, the emergence of the Global Broadcast Service (GBS) with its ability to deliver data to the warfigher at data rates approaching 25Mbps is creating unprecedented opportunities. Commercial very small aperture terminal (VSAT) networks, while not typically offering quite as much throughput, often support Mbps capabilities. However, it is often the case that high data rates to the warfighter are not available in the reverse direction. NRL has demonstrated asymmetric networking using: GBS as the forward channel and low-cost organic backchannels for the return paths. Typical backchannel solutions include telephone (POTS), cellular phone, satellite mobile phone, commercially available VSAT, UHF FLTSAT, Inmarsat B, and tatical radio, Each of the backchannel solutions presents different data rare capabilities and bit error rates, but typical backchannel data rates range from 1.2Kbps to 160kbps. A typical GBS or VSAT "forward" channel operates in the 1-5Mbps range. A network built on such asymmetry presents challenges not typical of full duplex physical layer links. NRL has investigated the effect such asymmetry has on TCP, TCP Extended Window Option Selective Acknowledgements, and reliable multicast. The investigations have focused on the ability of each to efficiently transfer large data files to the warfighter. The investigative effort began with simulation and experimental efforts to document the effect on forward channel throughput for FTP and HTTP file transfers using backchannels ranging in data rate from 1.2Kbps to 2Mbps. Standard round trip time calculations for throughput based on window size limitations are not adequate for describing performance in highly asymmetric networks. Extended window option and selective acknowledgement enhancements to TCP simulated and experimental results are discussed. The use of reliable multicast to overcome rite basic windowing challenges and deliver data to multiple users simultaneously is addressed. C1 USN, Res Lab, Washington, DC 20375 USA. RP Krout, T (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM krout@itd.nrl.navy.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 1072 EP 1076 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600201 ER PT J AU Koplow, JP Kliner, DAV Goldberg, L AF Koplow, JP Kliner, DAV Goldberg, L TI UV generation by frequency quadrupling of a Yb-doped fiber amplifier SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE laser amplifiers; optical fiber amplifiers; optical frequency conversion; pulsed lasers; ultraviolet generation ID POLARIZATION AB The pulsed output of a Yb-doped fiber amplifier was frequency doubled and quadrupled to generate visible and UV radiation, When pumped with 150-200 mW at 980 nm and seeded at 1064 nm, the amplifier produced an average power of 90 mW at 1064 nm, 45 mW at 532 nm, and 1.4 mW at 266 nm, These results indicate that frequency-converted fiber lasers and amplifiers will be able to replace conventional tunable UV sources (e.g., frequency-converted dye lasers) in a number of applications. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. RP Koplow, JP (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 12 TC 13 Z9 13 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD JAN PY 1998 VL 10 IS 1 BP 75 EP 77 DI 10.1109/68.651111 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA YN129 UT WOS:000071136000025 ER PT J AU Williams, KJ Esman, RD Wilson, RB Kulick, JD AF Williams, KJ Esman, RD Wilson, RB Kulick, JD TI Differences in p-side and n-side illuminated p-i-n photodiode nonlinearities SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE nonlinear distortions; nonlinearities; photodetectors; photodiodes; p-i-n photodiodes; semiconductor device modeling; simulation ID MICROWAVE PHOTODETECTORS AB The advantages of illumination through the p-contact of p-i-n photodetectors are experimentally and numerically studied, Nonlinearity and compression current measurements are, compared to simulations of harmonic distortion for a 3-GHz p-side-illuminated photodiode to further our understanding of signal compression, It is shown that the 1-dB compression current may be improved by an order of magnitude for capacitively limited detectors simply by illumination from the p-side. This effect is attributed to the decreasing hole velocity at low electric fields and the steady-state carrier density distributions at high current levels. C1 USN, Res Lab, Washington, DC 20375 USA. Global Opteelect Grp, Somerville, NJ 08876 USA. RP Williams, KJ (reprint author), USN, Res Lab, Code 5670, Washington, DC 20375 USA. NR 8 TC 14 Z9 14 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD JAN PY 1998 VL 10 IS 1 BP 132 EP 134 DI 10.1109/68.651136 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA YN129 UT WOS:000071136000044 ER PT J AU Pace, PE Nishimura, BH Morris, WM Surratt, RE AF Pace, PE Nishimura, BH Morris, WM Surratt, RE TI Effectiveness calculations in captive-carry HIL missile simulator experiments SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB Electronic countermeasures (ECMs) are instrumental in altering the flight path of an incoming active threat missile. To determine the effectiveness of the ECM hardware-in-the-loop (HIL) threat missile simulators are tested in several types of experimental configurations (e.g., closed-loop in an anechoic chamber, open-loop captive-carry field tests on board an aircraft). A new class of modeling and simulation algorithms is presented that allows an accurate miss distance to be calculated from a high-bandwidth ECM captive-carry test result. The techniques combine the results from each test configuration and represent an improvement in evaluating an ECM effectiveness over a singly independent analysis. Anechoic chamber and captive-carry test results from an HIL antiship missile (ASM) simulator are used to demonstrate the algorithms and detail the feasibility of the approach. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. USN, Res Lab, Integrated EW Simulat Branch, Tact Elect Warfare Div, Washington, DC 20375 USA. RP Pace, PE (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Code EC Pc,1 Univ Circle, Monterey, CA 93943 USA. NR 8 TC 5 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD JAN PY 1998 VL 34 IS 1 BP 124 EP 136 DI 10.1109/7.640269 PG 13 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA YQ113 UT WOS:000071349800012 ER PT J AU Sletten, MA AF Sletten, MA TI Multipath scattering in ultrawide-band radar sea spikes SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE sea-surface electromagnetic scattering ID LOW GRAZING ANGLES; POLARIMETRIC RADAR; MICROWAVE BACKSCATTER; BREAKING WAVES; SURFACE; RESOLUTION; CLUTTER AB This paper presents sea-scatter data collected with an ultrawide-band (UWB) polarimetric radar system that indicates that multipath scattering plays an important role in the generation of sea spikes, The radar system used in this study produces short pulses with a bandwidth of approximately 3 GHz centered at 9 GHz for a range resolution of approximately 4 cm, Pulse-to-pulse switching allows collection of the microwave echoes produced by all four combinations of linear transmit and receive polarizations [vertical-transmit vertical-receive (VV), horizontal-transmit horizontal-receive (HH), horizontal-transmit vertical receive (HV), and vertical-transmit horizontal-receive (VH)] each of which is collected by a sampling oscilloscope utilizing equivalent time sampling. In June 1996, upwind sea scatter data at grazing angles of 10 degrees, 20 degrees, and 30 degrees were collected while-the system was deployed on a research pier on the Outer Banks of North Carolina, An analysis of the strongest echoes (sea spikes) from this data set is presented and discussed in this paper, First, the cumulative distribution functions are presented, Second, an increase of approximately 5 dB is shown to occur in the polarization ratio (HH/VV) of the strongest echoes as the grazing angle decreases from 30 degrees to 10 degrees, Third, differences in the spatial and spectral characteristics of the VV and HH spikes are described, Through comparisons with laboratory results and a simple scattering model, these observations are explained by the presence of a multibounce scattering mechanism, The use of the model to extract wave height from the sea-spike frequency response is also explored. C1 USN, Res Lab, Washington, DC 20375 USA. RP Sletten, MA (reprint author), USN, Res Lab, Code 7255, Washington, DC 20375 USA. NR 28 TC 17 Z9 17 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD JAN PY 1998 VL 46 IS 1 BP 45 EP 56 DI 10.1109/8.655450 PG 12 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA YR399 UT WOS:000071491300006 ER PT J AU Robertson, RC Iwasaki, H Kragh, M AF Robertson, RC Iwasaki, H Kragh, M TI Performance of a fast frequency-hopped noncoherent MFSK receiver with nonideal adaptive gain control SO IEEE TRANSACTIONS ON COMMUNICATIONS LA English DT Article; Proceedings Paper CT IEEE Military Communications Conference (MILCOM 95) CY NOV 05-08, 1995 CL SAN DIEGO, CALIFORNIA SP IEEE, IEEE Commun Soc, Armed Forces Commun & Electr Assoc DE diversity methods; fading channels; frequency-hop communication; Rayleigh channels; Rician channels; spread spectrum communication ID INTERFERENCE AB An error probability analysis is performed for an orthogonal noncoherent M-ary frequency-shift keying (MFSK) communication system employing fast frequency-hopped (FFH) spread spectrum with diversity, The signal is assumed to be transmitted through a frequency-nonselective slowly fading channel with partial-band noise interference, The partial-band interference is modeled as a Gaussian process. Both the information signal and the partial-band noise interference signal are assumed to be affected by channel fading; it is assumed that the two fading processes are independent and that channel fading need not necessarily affect the information signal and the interference signal in the same way, Each diversity reception is assumed to fade independently according to a Rician process, Adaptive gain control is employed to minimize partial-band interference effects, and the effect of inaccurate noise measurement on the ability of the adaptive gain control receiver to reject partial-band interference is examined, The effect of thermal noise is included in the analysis. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Robertson, RC (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. NR 10 TC 7 Z9 8 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0090-6778 J9 IEEE T COMMUN JI IEEE Trans. Commun. PD JAN PY 1998 VL 46 IS 1 BP 104 EP 114 DI 10.1109/26.655408 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA YR401 UT WOS:000071491500015 ER PT J AU McDevitt, RJ Das Peddada, S AF McDevitt, RJ Das Peddada, S TI An automated algorithm for cleaning and ordering the boundary points of a one-dimensional curve in a segmented image SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE boundary cleaning; chains; hulling; ice floes; traveling salesman problem ID ICE; TRACKING; MOTION AB Due to variability in the assignment of gray scale values, most edge detection algorithms produce undesirable edges inside and outside the object of a gray scale image. Also, the points of the edges formed by these algorithms may not be in a linear order. In this communications, a new automated algorithm is provided which removes the undesirable edges and linearly orders the remaining boundary points. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. Univ Virginia, Div Stat, Charlottesville, VA 22903 USA. RP McDevitt, RJ (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. RI Peddada, Shyamal/D-1278-2012 NR 9 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JAN PY 1998 VL 36 IS 1 BP 307 EP 312 DI 10.1109/36.655340 PG 6 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA YT522 UT WOS:000071615500028 ER PT J AU Kamgar-Parsi, B Rosenblum, LJ Belcher, EO AF Kamgar-Parsi, B Rosenblum, LJ Belcher, EO TI Underwater imaging with a moving acoustic lens SO IEEE TRANSACTIONS ON IMAGE PROCESSING LA English DT Article DE acoustic imaging; acoustic lens; pass registration; 3-D underwater imaging ID SYSTEM AB The acoustic lens is a high-resolution, forward-looking sonar for three-dimensional (3-D) underwater imaging, In this paper, we discuss processing the lens data for recreating and visualizing the scene, Acoustical imaging, compared to optical imaging, is sparse and low resolution, To achieve higher resolution, we obtain a denser sample by mounting the lens on a moving platform and passing over the scene, This introduces the problem of data fusion from multiple overlapping views for scene formation, which we discuss. We also discuss the improvements in object reconstruction by combining data from several passes over an object, We present algorithms for pass registration and show that this process can be done with enough accuracy to improve the image and provide greater detail about the object, The results of in-water experiments show the degree to which size and shape can be obtained under (nearly) ideal conditions. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Washington, Appl Phys Lab, Seattle, WA 98105 USA. RP USN, Res Lab, Washington, DC 20375 USA. EM behzad@ait.nrl.navy.mil NR 21 TC 14 Z9 14 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1057-7149 EI 1941-0042 J9 IEEE T IMAGE PROCESS JI IEEE Trans. Image Process. PD JAN PY 1998 VL 7 IS 1 BP 91 EP 99 DI 10.1109/83.650853 PG 9 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA YM900 UT WOS:000071113100008 PM 18267382 ER PT J AU Schultz, A Wechsler, H AF Schultz, A Wechsler, H TI A discrete dynamics model for synchronization of pulse-coupled oscillators SO IEEE TRANSACTIONS ON NEURAL NETWORKS LA English DT Article DE binding problem; coupled oscillators; neural networks; nonlinear dynamics; perception; sensor fusion; synchronization AB Biological information processing systems employ a variety of feature types, It has been postulated that oscillator synchronization is the mechanism for binding these features together to realize coherent perception, A discrete dynamic model of a coupled system of oscillators is presented here, The network of oscillators converges to a state where subpopulations of cells become phase synchronized, It has potential applications to describing biological perception as well as for the construction of multifeature pattern recognition systems, It is shown that this model can be used to detect the presence of short line segments in the boundary contour of an object, The Hough Transform, which is the standard method for detecting curve segments of a specified shape in an image was found not to be effective for this application, Implementation of the discrete dynamics model of oscillator synchronization is much easier than the differential equation models that have appeared in the literature, A systematic numerical investigation of the convergence properties of the model has been performed and it is shown that the discrete dynamics model can scale up to large number of oscillators. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. George Mason Univ, Dept Comp Sci, Fairfax, VA 22030 USA. RP Schultz, A (reprint author), USN, Res Lab, Div Radar, Washington, DC 20375 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9227 J9 IEEE T NEURAL NETWOR JI IEEE Trans. Neural Netw. PD JAN PY 1998 VL 9 IS 1 BP 51 EP 57 DI 10.1109/72.655029 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA YR386 UT WOS:000071490200006 PM 18252429 ER PT J AU Adelman, L Christian, M Gualtieri, J Johnson, KL AF Adelman, L Christian, M Gualtieri, J Johnson, KL TI Examining the effects of cognitive consistency between training and displays SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART A-SYSTEMS AND HUMANS LA English DT Article DE decision making; decision support systems; human factors; man-machine systems ID AIR DEFENSE OFFICERS; INFORMATION ORDER; PERFORMANCE AB An experiment was performed testing the "display cognitive consistency hypothesis" proposed in [2]. This hypothesis states that the effectiveness of a display format for decision-aiding systems depends on the consistency between how the system displays its reasoning process and how the person is processing the information. Results of an experiment using a simulated Army air defense task and college students found support for the hypothesis, but only at a situation-specific, not global level. Although unexpected, these results were consistent with other research indicating the importance of situation-specific context for understanding judgment and decision processes in individual and group settings. C1 George Mason Univ, Sch Informat Technol & Engn, Dept Operat Res & Engn, Fairfax, VA 22030 USA. Value Behav Hlth, Falls Church, VA 22042 USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. Univ Iowa, Dept Psychol, Iowa City, IA 52242 USA. RP Adelman, L (reprint author), George Mason Univ, Sch Informat Technol & Engn, Dept Operat Res & Engn, Fairfax, VA 22030 USA. NR 21 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1083-4427 J9 IEEE T SYST MAN CY A JI IEEE Trans. Syst. Man Cybern. Paart A-Syst. Hum. PD JAN PY 1998 VL 28 IS 1 BP 1 EP 16 DI 10.1109/3468.650317 PG 16 WC Computer Science, Cybernetics; Computer Science, Theory & Methods SC Computer Science GA YM436 UT WOS:000071063300001 ER PT B AU Menozzi, A Chow, MY Cho, CP AF Menozzi, A Chow, MY Cho, CP GP IEEE TI Intelligent training of a multi-resolution associative memory network SO IEEE WORLD CONGRESS ON COMPUTATIONAL INTELLIGENCE LA English DT Proceedings Paper CT 2nd IEEE World Congress on Computational Intelligence (WCCI 98) CY MAY 04-09, 1998 CL ANCHORAGE, AK SP Int Neural Network Soc, IEEE, Neural Networks Council, IEEE, Alaska Sect AB New challenges in US Navy tactical vehicle applications, such as quiet electric motors and unmanned undersea vehicles (UUVs), require flexible adaptive structures for real-time intelligent system identification and control tasks. Due to its speed of computation and linear learning behavior, the architecture of lattice-based associative memory networks is particularly attractive. The main problem of these networks; is the curse of dimensionality, which means that the memory requirement is exponentially dependent on the input dimension. In this paper, a novel structure called multi-resolution associative memory (MAM) network is proposed to overcame the curse of dimensionality. Preliminary simulations and real-rime experiments are performed using this structure, and the results are discussed. A fuzzy rule-base system is also proposed as a method to implement the heuristic that is at the heart of the MAM network's training algorithm. C1 USN, Undersea Warfare Ctr, Washington, DC 20350 USA. RP Menozzi, A (reprint author), USN, Undersea Warfare Ctr, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4860-5 PY 1998 BP 12 EP 17 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Engineering, Electrical & Electronic; Medical Informatics; Neurosciences SC Computer Science; Engineering; Medical Informatics; Neurosciences & Neurology GA BL15D UT WOS:000074493400003 ER PT B AU Barrows, GL AF Barrows, GL GP IEEE TI Stochastic Hebbian learning with binary synapses SO IEEE WORLD CONGRESS ON COMPUTATIONAL INTELLIGENCE LA English DT Proceedings Paper CT 2nd IEEE World Congress on Computational Intelligence (WCCI 98) CY MAY 04-09, 1998 CL ANCHORAGE, AK SP Int Neural Network Soc, IEEE, Neural Networks Council, IEEE, Alaska Sect AB This paper explores a variant of Hebbian learning in which binary synapses are updated stochastically rather than deterministically. In this variant, a single potentiation or depression event is implemented by setting a synapse weight respectively to "one" or "zero" with a finite probability, if it is not this value already. This learning rule is compared to the conventional Hebbian rule where a continuously valued synapse moves a fraction towards 10. or 0.0. It is shown that given a set of input-output pattern pairs, the expected value of a particular synapse is the same for both learning rules. Also as the network size and the input activity levels increase, the signal to noise ratio of the dendritic sums approaches infinity. These stochastic binary synapses are presented as a viable mechanism for the VLSI implementation of Hebbian-based neural networks. C1 USN, Res Lab, Tact Elect Warfare Div, Washington, DC 20375 USA. RP Barrows, GL (reprint author), USN, Res Lab, Tact Elect Warfare Div, Code 5720, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4860-5 PY 1998 BP 525 EP 530 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Engineering, Electrical & Electronic; Medical Informatics; Neurosciences SC Computer Science; Engineering; Medical Informatics; Neurosciences & Neurology GA BL15D UT WOS:000074493400097 ER PT B AU Sellami, L Newcomb, RW Ferrandez, JM Rodellar, V Gomez, P Roa, L AF Sellami, L Newcomb, RW Ferrandez, JM Rodellar, V Gomez, P Roa, L GP IEEE TI Analog VLSI circuits for learning rate adaptation in self-organizing neural networks SO IEEE WORLD CONGRESS ON COMPUTATIONAL INTELLIGENCE LA English DT Proceedings Paper CT 2nd IEEE World Congress on Computational Intelligence (WCCI 98) CY MAY 04-09, 1998 CL ANCHORAGE, AK SP Int Neural Network Soc, IEEE, Neural Networks Council, IEEE, Alaska Sect AB In this paper, we present analog VLSI circuits for the learning rate adaptation in self-organizing neural networks using the Mulier-Cherkassky learning rate adapted to the continuous-time case. The circuit design uses the solution of the Riccati equation as a basis for implementing the learning rate schedule. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. RP Sellami, L (reprint author), USN Acad, Dept Elect Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4860-5 PY 1998 BP 541 EP 546 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Engineering, Electrical & Electronic; Medical Informatics; Neurosciences SC Computer Science; Engineering; Medical Informatics; Neurosciences & Neurology GA BL15D UT WOS:000074493400100 ER PT B AU Ainsworth, TL Lee, JS AF Ainsworth, TL Lee, JS BE Stein, TI TI A joint adaptive interferometric phase unwrapping and filtering algorithm SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB SAR interferometry has come to the fore with the realization of the applicability and the general availability of interferometric data. With the widespread use of interferometry come problems concerning analysis and interpretation. Two aspects of these problems are phase unwrapping and speckle filtering. Here we present a joint phase unwrapping and filtering algorithm that optimally extracts the absolute phase from the relative phase via an adaptive weighted least-square method. SIR-C/X-SAR interferometric images of Mt. Etna, Italy are used to illustrate the method. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Ainsworth, TL (reprint author), USN, Res Lab, Remote Sensing Div, Code 7263, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 71 EP 73 DI 10.1109/IGARSS.1998.702802 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100024 ER PT B AU Turk, FJ Marzano, FS Smith, EA Mugnai, A AF Turk, FJ Marzano, FS Smith, EA Mugnai, A BE Stein, TI TI Using coincident SSM/I and infrared geostationary satellite data for rapid updates of rainfall SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci C1 USN, Res Lab, Marine Meteorol Div, Monterey, CA 93940 USA. RP Turk, FJ (reprint author), USN, Res Lab, Marine Meteorol Div, 7 Grace Hopper Ave, Monterey, CA 93940 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 150 EP 152 DI 10.1109/IGARSS.1998.702830 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100050 ER PT B AU Hwang, PA Krabill, WB Wright, W Swift, RN Walsh, EJ AF Hwang, PA Krabill, WB Wright, W Swift, RN Walsh, EJ BE Stein, TI TI Airborne scanning lidar and video measurements of coastal waves SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB A scanning lidar system provides high-resolution two-dimensional measurements of the ocean wave displacement. The airborne operation further enhances the speed of data acquisition. These properties offer a capability for rapid characterization of the ocean wave environment. In addition to the active ranging, the scanning optics can obtain passive measurements of the surface emissivity. This yields a digital image of the surface brightness "on the fly." Processed into a binary image, the measurements can provide the statistical properties of the spatial distribution of breaking waves. Technical specifications of the system and examples of applications are presented. C1 USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. RP Hwang, PA (reprint author), USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 192 EP 194 DI 10.1109/IGARSS.1998.702849 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100064 ER PT B AU Leighton, R Smith, G Tang, S AF Leighton, R Smith, G Tang, S BE Stein, TI TI A comparison of simulated and experimental IR measurements at low to moderate wind speeds. SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB The surface temperature field due to free-convection and/or forced turbulence at low to moderate wind speeds is examined experimentally and numerically. The objective of the research is to examine the scaling of the thermal boundary layer as the flow evolves from a free-convection regime to a shear-driven regime. The information will be used to assess models of the thermal boundary layer as the turbulence transitions from free-convection to fsheared turbulence at low wind speeds. The experiments were performed at the University of Delaware's Air-Sea Interaction Laboratory Wind-Wave-Current facility using an Amber Model 4256 IR Camera sensitive to image the air-water interface. The numerical simulations were performed using a spectral algorithm. A constant heat flux boundary condition is used in conjunction with a rigid lid approximation to model the free-surface. All fluid properties are held constant. A Boussinesq approximation is used to represent the temperature effects on buoyancy. The effect of the wind is modeled as a steady sheer stress acting on the free-surface. For the low wind speeds, the dominant physical process is the ascension of a warm plume into the wind-sheared near-surface region. The surface temperature exhibits a characteristic fish-scale pattern. As the flow transitions from free-convection to forced turbulence, a similar, but more complicated thermal pattern evolves. Some of the thermal structure in the laboratory experiments is similar to that observed in simulations of forced turbulence near a free-surface. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Leighton, R (reprint author), USN, Res Lab, Remote Sensing Div, Code 7253, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 481 EP 483 DI 10.1109/IGARSS.1998.702946 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100158 ER PT B AU McKeown, W AF McKeown, W BE Stein, TI TI Looking inside the ocean skin: Differential absorption techniques to sense the interface temperature gradient SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP McKeown, W (reprint author), USN, Res Lab, Code 7340, Stennis Space Ctr, MS 39529 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 490 EP 492 DI 10.1109/IGARSS.1998.702949 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100161 ER PT B AU Carroll, PJ Lathrop, JD McCormick, JF Summey, DC Chao, TH Chutjian, A Wright, J AF Carroll, PJ Lathrop, JD McCormick, JF Summey, DC Chao, TH Chutjian, A Wright, J BE Stein, TI TI Mobile underwater debris survey system (MUDSS) SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB This paper reports on the development of MUDSS, a multi-sensor system for the surveying of underwater ordinance and explosive waste (OEW) in shallow water (10' to 200'). The MUDSS concept and mode of operation are described and operational performance of the MUDSS state-of-the-art (SOA) sensors is presented from preliminary tests against a range of OEW targets. MUDSS employs advanced real-time processing and data fusion techniques to improve target detection in the presence of clutter, a significant problem in many shallow water sites of interest, MUDSS is expected to provide a substantial and unmatched capability to accurately survey underwater sites as the first step to remediation. C1 USN, Ctr Surface Warfare, Dahlgren Div, Coastal Syst Stn, Panama City, FL 32407 USA. RP Carroll, PJ (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Coastal Syst Stn, Code R23, Panama City, FL 32407 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 613 EP 617 DI 10.1109/IGARSS.1998.699528 PG 5 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100200 ER PT B AU Christoff, JT Fernandez, JE AF Christoff, JT Fernandez, JE BE Stein, TI TI Dual frequency synthetic aperture imaging sonar SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci C1 USN, Ctr Surface Warfare, Coastal Syst Stn, Dalhgren Div, Panama City, FL 32407 USA. RP Christoff, JT (reprint author), USN, Ctr Surface Warfare, Coastal Syst Stn, Dalhgren Div, Code R21,6703 W Hwy 98, Panama City, FL 32407 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 624 EP 626 DI 10.1109/IGARSS.1998.699531 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100203 ER PT B AU Haltrin, VI AF Haltrin, VI BE Stein, TI TI An analytic Fournier-Forand scattering phase function as an alternative to the Henyey-Greenstein phase function in hydrologic optics SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB This work presents results of numerical analysis of the Fournier-Forand scattering phase function as an alternative to the Henyey-Greenstein phase function in hydrological optics. A number of equations are derived that connect different integral parameters of the Fournier-Forand phase function, including the normalization coefficient, with the parameters of this function. The Mathematica and FORTRAN programs, that computes the Fournier-Forand scattering phase function and some of its integral characteristics, are released for public use. C1 USN, Res Lab, Ocean Sci Branch, Stennis Space Ctr, MS 39529 USA. RP Haltrin, VI (reprint author), USN, Res Lab, Ocean Sci Branch, Code 7331, Stennis Space Ctr, MS 39529 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 910 EP 912 DI 10.1109/IGARSS.1998.699623 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100295 ER PT B AU Haltrin, VI AF Haltrin, VI BE Stein, TI TI Spectral relative clarity of Black and Aegean Seas SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB The data on relative clarity or visibility of blue, green, red, and white (Secchi) disks measured in 1984 at the Black and Aegean seas during the 9(th) trip of the research vessel "Professor Kolesnikov" are presented. The analysis of results of measurements show strong correlation between visibilities of colored and Secchi disk. The regressional relationship between visibilities of blue, green and red disks and the visibility of the Secchi (white) disk are given and discussed. C1 USN, Res Lab, Ocean Sci Branch, Stennis Space Ctr, MS 39529 USA. RP Haltrin, VI (reprint author), USN, Res Lab, Ocean Sci Branch, Code 7331, Stennis Space Ctr, MS 39529 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 913 EP 915 DI 10.1109/IGARSS.1998.699624 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100296 ER PT B AU Kwak, S Choi, J AF Kwak, S Choi, J BE Stein, TI TI Propagation anomaly in the tropospheric atmosphere SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB Meteorological data has been processed to investigate RF propagation anomalies in troposhperic region from ground to 27 Km in space. There are two major dominant factors in tropospheric radio frequency wave propagation - angular bending and time delay. The correction measures of these two tropospheric propagation problems have been proposed based on model-cased or empirical measurements in terms of frequencies and climatic regions over the years to reduce propagation errors in telecommunication systems :link analysis. This paper describes the performance of different climatological database and tropospheric models. A database has been developed to provide enough information for analyzing many different phenomena of nonionized atmosphere in terms of refractivity, time delay, range error, and angle of arrival. A combined modified exponential model and the stratified range/angle error model, which is developed by tropospheric research team at NRL, is utilized. The proposed tropospheric model, a modified exponential model, outperforms in the accuracy improvement of range and time delay errors in the low elevation angle below 10 degree to negative degree while surface weather data and reference height are required only to run ray-tracing algorithms for range, time delay, and angle of arrival error. This readily accessible tropospheric model can be applied to topographic survey and the improved accuracy of remote sensing ( such as imagery and mapping of resource by optical sensors) of land and ocean. C1 USN, Res Lab, Space Syst Dev Dept, Washington, DC 20375 USA. RP Kwak, S (reprint author), USN, Res Lab, Space Syst Dev Dept, Code 8140-2,4555 Overlook Ave Sw, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 1417 EP 1419 DI 10.1109/IGARSS.1998.691466 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100459 ER PT B AU Gaiser, P Poe, G St Germain, K AF Gaiser, P Poe, G St Germain, K BE Stein, TI TI Critical design issues for space borne polarimetric radiometry SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB Polarimetric microwave radiometry has received much attention in recent years as a potential tool for measuring the ocean surface wind vector. Several airborne sensors have been built and collected valuable data. This paper describes some of the important design issues that must be addressed to deploy successfully a satellite-based polarimetric microwave radiometer. C1 USN, Res Lab, Washington, DC 20375 USA. RP Gaiser, P (reprint author), USN, Res Lab, Code 7223, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 1698 EP 1700 DI 10.1109/IGARSS.1998.692435 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100549 ER PT B AU Jordan, MS Wash, CH Durkee, PA Veefkind, P de Leeuw, G Smith, MH Hill, MK AF Jordan, MS Wash, CH Durkee, PA Veefkind, P de Leeuw, G Smith, MH Hill, MK BE Stein, TI TI Satellite and ship-based lidar measurements of optical depth during EOPACE SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci C1 USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Jordan, MS (reprint author), USN, Postgrad Sch, Dept Meteorol, 589 Dyer Rd,Room 254, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2131 EP 2135 DI 10.1109/IGARSS.1998.703764 PG 5 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100689 ER PT B AU Gao, BC Kaufman, YJ Han, W AF Gao, BC Kaufman, YJ Han, W BE Stein, TI TI Retrieval of column water vapor amount from MODIS channels near 1 mu m SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Gao, BC (reprint author), USN, Res Lab, Remote Sensing Div, Code 7212,4555 Overlook Ave, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2169 EP 2170 DI 10.1109/IGARSS.1998.703775 PG 2 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100700 ER PT B AU Lee, JS Grunes, MR Ainsworth, TL Du, L Schuler, DL Cloude, SR AF Lee, JS Grunes, MR Ainsworth, TL Du, L Schuler, DL Cloude, SR BE Stein, TI TI Unsupervised classification using polarimetric decomposition and complex Wishart classifier SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB In this paper, we propose a new method for unsupervised classification of terrain types and man-made objects using polarimetric SAR data. This technique is a combination of the unsupervised classification based on the polarimetric target decomposition (Cloude and Pottier, 1997) and the maximum likelihood classifier based on the complex Wishart distribution (Lee et at. 1994). The advantage of this approach is that clusters may be identified by the scattering mechanisms from the target decomposition. The effectiveness of this algorithm is demonstrated using JPL/AIRSAR and SIR-C polarimetric SAR images. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Lee, JS (reprint author), USN, Res Lab, Remote Sensing Div, Code 7263, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 1 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2178 EP 2180 DI 10.1109/IGARSS.1998.703778 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100703 ER PT B AU Schuler, DL Lee, JS AF Schuler, DL Lee, JS BE Stein, TI TI Terrain slope and surface roughness studies using circularly polarized SAR backscatter SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB In this paper we use a new SAR technique for measurement of terrain slopes in the azimuthal (along-track) direction for correction of terrain slope-related polarimetric effects in SAR surface roughness, or soil moisture, inversion studies. A second goal is determination of the sensitivity of a circular polarization correlation function for the measurement of terrain slopes and surface roughness. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Schuler, DL (reprint author), USN, Res Lab, Remote Sensing Div, Code 7263, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2187 EP 2189 DI 10.1109/IGARSS.1998.703781 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100706 ER PT B AU Sletten, MA Marmorino, GO Donato, TF AF Sletten, MA Marmorino, GO Donato, TF BE Stein, TI TI An airborne, real-aperture radar study of the Chesapeake Bay Outflow Plume SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB The Naval Research Laboratory (NRL) has recently utilized an airborne, real aperture radar (RAR) to study the fronts associated with the outflow from the Chesapeake Bay. During May 1997, the system was flown near the mouth of the Chesapeake Bay as part of the Chesapeake Bay Outflow Plume Experiment (COPE). This paper presents a summary of the RAR operations and of the data collected during the exercise. The plume front positions, as determined from the X-band RAR imagery, are presented for four cases, spanning the full semidiurnal tidal cycle over the course of approximately two weeks. C1 USN, Res Lab, Washington, DC 20375 USA. RP Sletten, MA (reprint author), USN, Res Lab, Code 7255,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2198 EP 2200 DI 10.1109/IGARSS.1998.703785 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100710 ER PT B AU Bachmann, CM Sletten, ME Donato, TF AF Bachmann, CM Sletten, ME Donato, TF BE Stein, TI TI Automated estimation of currents from surfactant flow in RAR and SAR imagery using projection pursuit methods SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB This paper describes methods which are being developed to automate the detection and tracking of surfactant flow for the purpose of estimating ocean surface currents. C1 USN, Res Lab, Remote Sensing Div, Remote Sensing Hydrodynam Branch, Washington, DC 20375 USA. RP Bachmann, CM (reprint author), USN, Res Lab, Remote Sensing Div, Remote Sensing Hydrodynam Branch, Code 7255, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2201 EP 2203 DI 10.1109/IGARSS.1998.703786 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100711 ER PT B AU Trizna, DB AF Trizna, DB BE Stein, TI TI Dual polarized RCS grazing angle characteristics of internal gravity waves SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB Grazing angle dependencies of radar cross section (RCS) are shown to differ for horizontally (HH) and vertically (VV) polarized X-band marine radar sea scatter from internal gravity wave (IGW) spatial modulations. For these internal gravity waves, observed off the coast of North Carolina, an IGW crest-to-trough modulation of 30-dB is observed at HH at 1 degrees, but only 10 dB at VV. The HH RCS decreases with increasing gazing angle, roughly to the minus one power, whereas VV RCS increases as for the composite model, but only to the first power. The HH/VV RCS ratio is 10 dB at 1 degrees, again opposite that expected from the two scale model, and decreases to -10 dB at 10 degrees grazing. The two scale model with wave-current modulation of short waves by wave-current interaction predicts a decrease in modulation as grazing is approached, opposite the results presented here. We suggest an influence of wave breaking radar scatter sources to explain these internal wave results, similar to arguments made for breaking wave scatter occurring near fronts. C1 USN, Res Lab, Washington, DC 20375 USA. RP Trizna, DB (reprint author), USN, Res Lab, Code 7255,4555 Overlook Ave, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2213 EP 2215 DI 10.1109/IGARSS.1998.703790 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100715 ER PT B AU St Germain, KM Poe, G Gaiser, P AF St Germain, KM Poe, G Gaiser, P BE Stein, TI TI Modeling of the polarimetric microwave signal due to ocean surface wind vector SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB Aircraft observations of the azimuthal dependence of brightness temperature on wind direction indicate that the behavior is dominated by two sinusoidal functions. A two-scale model was developed to explain this behavior over all microwave frequencies and angles of incidence. A Fourier analysis of the data, along with a radiative transfer model of the atmosphere, provided an efficient means of simulating observations from a satellite platform for "global" conditions. This model was used to develop and test a simple wind vector retrieval algorithm. The retrieval analysis indicated that given expected noise, biases, and coupling errors for a satellite system, the wind direction can be retrieved to within 18 degrees if a combination of channels ranging from 6.8 to 37 GHz is used. These results were valid over atmospheric conditions ranging from clear skies to very heavy cloud cover. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP St Germain, KM (reprint author), USN, Res Lab, Remote Sensing Div, Code 7223,4555 Overlook Ave, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 2304 EP 2306 DI 10.1109/IGARSS.1998.702196 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100744 ER PT J AU Thayer, L AF Thayer, L TI Readers divided on certification issue SO IIE SOLUTIONS LA English DT Letter C1 USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Thayer, L (reprint author), USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INST INDUSTRIAL ENGINEERS PI NORCROSS PA 25 TECHNOLOGY PARK/ATLANTA, NORCROSS, GA 30092 USA SN 1085-1259 J9 IIE SOLUTIONS JI IIE Solut. PD JAN PY 1998 VL 30 IS 1 BP 6 EP 6 PG 1 WC Engineering, Industrial SC Engineering GA YP983 UT WOS:000071335600005 ER PT S AU Gaberson, HA AF Gaberson, HA GP SOC EXPT MECH INC SOC EXPT MECH INC TI Determination and animation of machinery rigid body operating deflection shapes with MATLAB SO IMAC - PROCEEDINGS OF THE 16TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 16th International Modal Analysis Conference (IMAC) - Model Updating and Correlation CY FEB 02-05, 1998 CL SANTA BARBARA, CA SP Soc Exptl Mech AB Many times engineers want to animate an operating deflection shapes (ODS) model of a machine with more points then have been actually measured. It makes for a more realistic looking model to clarify the motions. For frequencies below the first mode frequency of the machine housing, it is reasonable to assert that the machine component, e.g., a motor, pump, generator, moves a rigid body. In this frequency range, each rigid body has three centroidal linear and angular accelerations, velocities, or displacements. These can be determined ideally with only six motion measurements. The angular motions will be small and thus commutative. This allows one to calculate the motions of every point in the rigid body. This paper presents a method of measuring and computing the six centroidal motion components for each rigid body, and building on previous work on doing ODS with MATLAB, shows how to calculate, draw, and animate the rigid body motions in MATLAB. C1 USN, Facil Engn Serv Ctr, Port Hueneme, CA 93043 USA. RP Gaberson, HA (reprint author), USN, Facil Engn Serv Ctr, Port Hueneme, CA 93043 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-59-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3243 BP 1526 EP 1532 PG 7 WC Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BK40H UT WOS:000072063100219 ER PT S AU Fisher, J Baumback, M Bowles, J Grossmann, J Antoniades, J AF Fisher, J Baumback, M Bowles, J Grossmann, J Antoniades, J BE Descour, MR Shen, SS TI Comparison of low-cost hyperspectral sensors SO IMAGING SPECTROMETRY IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry IV CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE imaging spectrograph; hyperspectral; convex holographic gratings; holographic transmission gratings AB Recent advances in large format detector arrays and holographic diffraction gratings have made possible the development of imaging spectrographs with high sensitivity and resolution, at relatively low component cost (<$100K.) Several airborne instruments have been built for the visible and near infrared spectral band with 10-nm resolution, and SNR of 200:1. Three instruments are compared, an all-reflective spectrograph using a convex grating in an Offner configuration, and two off-the-shelf transmission grating spectrographs using volume holograms. The camera is a 1024 x 1024 frame transfer, back-thinned CCD, with four taps for obtaining high frame rates. Performance and scan data is presented and compared to the design for image quality, distortion, and throughput. C1 USN, Res Lab, Washington, DC 20375 USA. RP Fisher, J (reprint author), USN, Res Lab, 455 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 33 Z9 33 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2893-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3438 BP 23 EP 30 DI 10.1117/12.328112 PG 8 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BL91T UT WOS:000077137900003 ER PT S AU Kappus, ME Davis, CO Rhea, WJ AF Kappus, ME Davis, CO Rhea, WJ BE Descour, MR Shen, SS TI Bathymetry from fusion of airborne hyperspectral and laser data SO IMAGING SPECTROMETRY IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry IV CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE bathymetry; data fusion; endmember; littoral AB Airborne hyperspectral and nadir-viewing laser data can be combined to ascertain shallow water bathymetry. The combination emphasizes the advantages and overcomes the disadvantages of each method used alone. For laser systems, both the hardware and software for obtaining off-nadir measurements are complicated and expensive, while for the nadir view the conversion of laser pulse travel time to depth is straightforward. The hyperspectral systems can easily collect data in a full swath, but interpretation for water depth requires careful calibration and correction for transmittance through the atmosphere and water. Relative depths are apparent in displays of several subsets of hyperspectral data, for example, single blue-green wavelengths, endmembers that represent the pure water component of the data, or ratios of deep to shallow water endmembers. A relationship between one of these values and the depth measured by the aligned nadir laser can be determined, and then applied to the rest of the swath to obtain depth in physical units for the entire area covered. We demonstrate this technique using bathymetric charts as a proxy for laser data, and hyperspectral data taken by AVIRIS over Lake Tahoe and Key West. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kappus, ME (reprint author), USN, Res Lab, Code 7210, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2893-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3438 BP 40 EP 51 DI 10.1117/12.328121 PG 12 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BL91T UT WOS:000077137900005 ER PT S AU Bowles, J Daniel, M Grossmann, J Antoniades, J Baumback, M Palmadesso, P AF Bowles, J Daniel, M Grossmann, J Antoniades, J Baumback, M Palmadesso, P BE Descour, MR Shen, SS TI Comparison of output from ORASIS and Pixel Purity calculations. SO IMAGING SPECTROMETRY IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry IV CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn AB We compare the results produced by the NRL ORASIS algorithm with those produced by ENVI's Pixel Purity Index (PPI). Both procedures attempt to find appropriate estimations of the constituent endmembers. In ENVI's PPI, each spectrum in the scene is given a pixel purity index according to the number of times (in a given set of trials) its projection to a random linear subspace is extreme. The spectra with sufficiently high index are then examined with ENVI's n-D Visualizer and endmembers are chosen by inspection. The endmembers thus obtained are averages of spectra in the scene. The ORASIS algorithm begins with a vector quantization procedure producing a list of distinct spectra referred to as exemplars. An altered Gram-Schmidt process is then applied to the exemplars to determine their dimensionality and initial estimates of the endmembers. This is followed by a shrink-wrap - the candidate endmembers are adjusted to form a simplex that best fits the data and thereby determines the final endmembers. The comparison is made on the output from two data cubes. Using the first 64 bands of the AVIRIS 1996 Florida Keys scene and the last 55 bands of the Cuprite scene, the outputs are similar. For all pure pixels with indexes above a certain threshold an exemplar exists that is either identically the same spectrum or within the ORASIS set error angle. Subsequently, the use of ENVI's n-D visualizer allows the viewing of clusters in the data, which allows the selection of endmembers. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Bowles, J (reprint author), USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. NR 0 TC 24 Z9 24 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2893-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3438 BP 148 EP 156 DI 10.1117/12.328097 PG 9 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BL91T UT WOS:000077137900015 ER PT J AU Alexander, J Fikes, J Hoffman, S Franke, E Sacci, J Appella, E Chisari, FV Guidotti, LG Chesnut, RW Livingston, B Sette, A AF Alexander, J Fikes, J Hoffman, S Franke, E Sacci, J Appella, E Chisari, FV Guidotti, LG Chesnut, RW Livingston, B Sette, A TI The optimization of helper T lymphocyte (HTL) function in vaccine development SO IMMUNOLOGIC RESEARCH LA English DT Review DE PAN DR T cell helper epitopes (PADRE); peptide-based vaccines; malaria; HBV ID HEPATITIS-B VIRUS; MHC CLASS-II; COMPLEX-CLASS-II; NATURALLY PROCESSED PEPTIDES; MELANOMA ANTIGEN GP100; CELL EPITOPES; IMMUNE-RESPONSE; HLA-DR; PROMISCUOUS RECOGNITION; 3-DIMENSIONAL STRUCTURE AB Helper T lymphocyte (HTL) responses play an important role in the induction of both humoral and cellular immune responses. Therefore, HTL epitopes are likely to be a crucial component of prophylactic and immunotherapeutic vaccines. For this reason, Pan DR helper T cell epitopes (PADRE), engineered to bind most common HLA-DR molecules with high affinity and act as powerful immunogens, were developed. Short linear peptide constructs comprising PADRE and Plasmodium-derived B cell epitopes induced antibody responses comparable to more complex multiple antigen peptides (MAP) constructs in mice. These antibody responses were composed mostly of the IgG subclass, reactive against intact sporozoites, inhibitory of schizont formation in liver invasion assays, and protective against sporozoite challenge in vivo. The PADRE HTL epitope has also been shown to augment the potency of vaccines designed to stimulate a cellular immune response. Using a HBV transgenic murine model, it was found that CTL tolerance was broken by PADRE-CTL epitope Lipopeptide, but not by a similar construct containing a conventional HTL epitope. There are a number of prophylactic vaccines that are of limited efficacy, require multiple boosts, and/or confer protection to only a fraction of the immunized population. Also, in the case of virally infected or cancerous cells, new immunotherapeutic vaccines that induce strong cellular immune responses are desirable. Therefore, optimization of HTL function by use of synthetic epitopes such as PADRE or pathogen-derived, broadly crossreactive epitopes holds promise for a new generation of highly efficacious vaccines. C1 Epimmune Inc, San Diego, CA USA. USN, Med Res Inst, Rockville, MD 20852 USA. NCI, NIH, Bethesda, MD 20892 USA. Scripps Res Inst, La Jolla, CA USA. RP Sette, A (reprint author), 6555 Nancy Dr,Suite 200, San Diego, CA 92121 USA. RI Chisari, Francis/A-3086-2008; OI Guidotti, Luca G./0000-0002-0205-2678; Chisari, Francis/0000-0002-4832-1044 FU NCI NIH HHS [R37 CA 40489]; NIAID NIH HHS [N01-AI-45241, R01 AI 2001] NR 145 TC 67 Z9 79 U1 1 U2 10 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0257-277X J9 IMMUNOL RES JI Immunol. Res. PY 1998 VL 18 IS 2 BP 79 EP 92 DI 10.1007/BF02788751 PG 14 WC Immunology SC Immunology GA 142HD UT WOS:000077193800002 PM 9844827 ER PT S AU Bewley, WW Vurgaftman, I Felix, CL Aifer, EH Meyer, JR Lin, CH Zhang, D Murry, SJ Pei, SS Ram-Mohan, LR AF Bewley, WW Vurgaftman, I Felix, CL Aifer, EH Meyer, JR Lin, CH Zhang, D Murry, SJ Pei, SS Ram-Mohan, LR BE Choi, HK Zory, PS TI Mid-IR type-II diode lasers SO IN-PLANE SEMICONDUCTOR LASERS: FROM ULTRAVIOLET TO MID-INFRARED II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on In-Plane Semiconductor Lasers - From Ultraviolet to Mid-Infrared II CY JAN 26-28, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE mid-infrared; type-II superlattice diode laser; semiconductor laser; Auger recombination; internal loss; current injection; optical pumping; InAs; GaSb AB A 2.9 mu m superlattice diode laser with an InAs/GaSb/Ga0.75In0.25Sb/GaSb active region displayed high temperature operation and low current injection thresholds. The maximum operating temperature was 260 K, and at 200 K the threshold current density was 1.1 kA/cm(2) and the quantum efficiency > 15%. The peak output power per facet for this laser exceeded 800 mW at 100 K and 200 mW at 200 K for a 0.05% duty cycle. For two similar lasers, internal losses were extracted from optical pumping experiments. The first laser was designed to minimize Auger recombination by avoiding resonances between the bandgap and intervalence transitions Cat zone center), while the second was designed to maximize these resonances. Internal losses for the Auger minimized(maximized) laser diode were 14(10) cm(-1) at T = 100 K, and rose rapidly to 51(120) cm(-1) at 200 K. However, Auger coefficients were suppressed (less than or equal to 1.6x10(-27) cm(6)/s at T = 260 K) for both samples when compared to a type-I material with a similar bandgap. For optical pumping, peak output powers up to 6.5 W per facet at 100 K and 3.5 W per facet at 180 K were obtained for these samples at lambda approximate to 3.1 mu m. C1 USN, Res Lab, Washington, DC 20375 USA. RP Bewley, WW (reprint author), USN, Res Lab, Code 5613, Washington, DC 20375 USA. RI Ram-Mohan, Ramdas/C-5167-2012 NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2723-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3284 BP 294 EP 305 DI 10.1117/12.304454 PG 12 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL04L UT WOS:000074112500033 ER PT S AU DeGiorgi, VG AF DeGiorgi, VG BE Sater, JM TI Integrated smart panel and support structure response SO INDUSTRIAL AND COMMERCIAL APPLICATIONS OF SMART STRUCTURES TECHNOLOGIES - SMART STRUCTURES AND MATERIALS 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Smart Structures and Materials 1998 - Industrial and Commercial Applications of Smart Structures Technologies CY MAR 03-05, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers, Soc Exptl Mech Inc, Amer Soc Mech Engineers, BF Goodrich Aerosp, USAF Res Lab, Def Adv Res Projects Agcy, Ceram Soc Japan, Intelligent Mat Forum, Japan, USA Res Off DE smart materials; finite element; ceramic actuators; structural response AB The performance of smart structures is a complex interaction between active and passive components. Active components, even when non-activated, can have an impact on structural performance and, conversely, structural characteristics of passive components can have a measurable impact on active component performance. The present work is an evaluation of the structural characteristics of an active panel designed for acoustic quieting. The support structure is included in the panel design as evaluated. Finite element methods are used to determine the active panel-support structure response. Two conditions are considered; a hollow unfilled support structure and the same structure filled with a polymer compound. Finite element models were defined so that stiffness values corresponding to the center of individual pistons could be determined. Superelement techniques were used to define mass and stiffness values representative of the combined active and support structure at the center of each piston. Results of interest obtained from the analyses include mode shapes, natural frequencies, and equivalent spring stuffiness for use in structural response models to represent the support structure. The effects on plate motion on piston performance cannot be obtained from this analysis, however mass and stiffness matrices for use in an integrated system model to determine piston head velocities can be obtained from this work. C1 USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. RP DeGiorgi, VG (reprint author), USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2770-5 J9 P SOC PHOTO-OPT INS PY 1998 VL 3326 BP 420 EP 427 DI 10.1117/12.310657 PG 8 WC Engineering, Aerospace; Engineering, Mechanical; Optics; Transportation SC Engineering; Optics; Transportation GA BL31K UT WOS:000075067700040 ER PT J AU Pile, JC Tribble, DR AF Pile, JC Tribble, DR TI Human dirofilarial infection in North America SO INFECTIOUS DISEASES IN CLINICAL PRACTICE LA English DT Article ID FLORIDA; IMMITIS C1 USN, Med Ctr, Div Infect Dis, Bethesda, MD 20889 USA. USN, Med Res Inst, Dept Infect Dis, Bethesda, MD USA. RP Pile, JC (reprint author), USN, Med Ctr, Div Infect Dis, Bethesda, MD 20889 USA. NR 17 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 1056-9103 J9 INFECT DIS CLIN PRAC JI Infect. Dis. Clin. Pract. PD JAN PY 1998 VL 7 IS 1 BP 54 EP 56 PG 3 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA YV725 UT WOS:000071856500012 ER PT J AU Kostoff, RN Eberhart, HJ Toothman, DR AF Kostoff, RN Eberhart, HJ Toothman, DR TI Database tomography for technical intelligence: A roadmap of the near-earth space science and technology literature SO INFORMATION PROCESSING & MANAGEMENT LA English DT Article AB Database Tomography (DT) is a system which includes algorithms for extracting multi-word phrase frequencies and performing phrase proximity analyses (relating physical closeness of the multi-word technical phrases to thematic relationships) on any type of large textual database. As an illustration of the DT process applied to the published literature, DT was used to derive technical intelligence from a near-earth space (NES) database derived from the Science Citation Index and the Engineering Compendex. Phase frequency analysis (the occurrence frequency of multi-word technical phrases) provided the pervasive technical themes of the space database, and the phrase proximity analysis provided the relationships among the pervasive technical themes. Bibliometric analysis of the NES literature supplemented the DT results by identifying: the recent most prolific NES authors; the journals which contain numerous NES papers; the institutions which produce numerous NES papers; the keywords most frequently specified by the NES authors; the authors whose works are cited most frequently in the NES papers; and the particular papers and journals cited most frequently in the NES papers. C1 Off Naval Res, Arlington, VA 22217 USA. USN, Air Warfare Ctr China Lake, China Lake, CA USA. DSTI Inc, Rockville, MD USA. RP Kostoff, RN (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. EM kosto-fr@onr.navy.mil NR 46 TC 48 Z9 49 U1 0 U2 8 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0306-4573 J9 INFORM PROCESS MANAG JI Inf. Process. Manage. PD JAN PY 1998 VL 34 IS 1 BP 69 EP 85 DI 10.1016/S0306-4573(97)00066-6 PG 17 WC Computer Science, Information Systems; Information Science & Library Science SC Computer Science; Information Science & Library Science GA ZA695 UT WOS:000072391800005 ER PT J AU Rowe, NC Frew, B AF Rowe, NC Frew, B TI Automatic caption localization for photographs on World Wide Web pages SO INFORMATION PROCESSING & MANAGEMENT LA English DT Article ID RETRIEVAL; IMAGES; TEXT AB A variety of software tools index text of the World Wide Web, but little attention has been paid to the many photographs. We explore the indirect method of locating for indexing the likely explicit and implicit captions of photographs. We use multimodal clues including the specific words used, the syntax, the surrounding layout of the Web page, and the general appearance of the associated image. Our MARIE-3 system thus avoids full image processing and full natural-language processing, but shows a surprising degree of success. Experiments with a semi-random set of Web pages showed 41% recall with 41% precision for the task of distinguishing captions from other text, and 70% recall with 30% precision. This is much better than chance since actual captions were only 1.4% of the text on pages with photographs. (C) 1998 Published by Elsevier Science Ltd. C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. RP Rowe, NC (reprint author), USN, Postgrad Sch, Dept Comp Sci, Code CS-RP, Monterey, CA 93943 USA. NR 11 TC 9 Z9 10 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0306-4573 J9 INFORM PROCESS MANAG JI Inf. Process. Manage. PD JAN PY 1998 VL 34 IS 1 BP 95 EP 107 DI 10.1016/S0306-4573(97)00048-4 PG 13 WC Computer Science, Information Systems; Information Science & Library Science SC Computer Science; Information Science & Library Science GA ZA695 UT WOS:000072391800007 ER PT S AU Yang, MJ Moore, WJ Bennett, BR Shanabrook, BV Cross, JO AF Yang, MJ Moore, WJ Bennett, BR Shanabrook, BV Cross, JO BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI The growth of type-II infrared laser structures SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB The MBE growth temperature for InAs/InGaSb/lnAs/AlSb mid-infrared lasers has been studied. It is found that the best growth temperature is between 370 degrees C and 420 degrees C. A growth temperature above this range will result in excessive interlayer mixing, which degrades the radiative efficiency. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yang, MJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 0 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 11 EP 12 PG 2 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400002 ER PT S AU Bewley, WW Felix, CL Aifer, EH Meyer, JR Goldberg, L Vurgaftman, I Chow, DH Selvig, E AF Bewley, WW Felix, CL Aifer, EH Meyer, JR Goldberg, L Vurgaftman, I Chow, DH Selvig, E BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Mid-IR vertical cavity surface-emitting lasers SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB An optically pumped mid-infrared vertical-cavity surface-emitting laser based on an active region with a "W" configuration of type-II antimonide quantum wells is reported. The emission wavelength of 2.9 mu m has a weak temperature variation (d lambda/dT approximate to 0.07 -0.09 nm/K), and the multimode linewidth is quite narrow (2.5-4 nm). Lasing is observed up to T = 280 K in pulsed mode and up to 160 K cw. Under cw excitation at T = 78 ii, the threshold pump power is as low as 4 mW for a 6 mu m spot, and the differential power conversion efficiency is 4.5%. C1 USN, Res Lab, Washington, DC 20375 USA. RP Bewley, WW (reprint author), USN, Res Lab, Code 5600, Washington, DC 20375 USA. RI Selvig, Espen/B-5122-2008 NR 0 TC 0 Z9 0 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 95 EP 100 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400013 ER PT S AU Luginbuhl, CB Henden, AA Vrba, FJ Guetter, HH AF Luginbuhl, CB Henden, AA Vrba, FJ Guetter, HH BE Fowler, AM TI Photometric linearization of the NICMOS-3 array SO INFRARED ASTRONOMICAL INSTRUMENTATION, PTS 1-2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Infrared Astronomical Instrumentation CY MAR 23-25, 1998 CL KONA, HI SP Int Soc Opt Engn, European So Observ DE NICMOS-3; photometric response; photometric linearization AB The inherent non-linearity in the photometric response of NICMOS-3 HgCdTe arrays can lead to photometric calibration errors of 1-2 percent or more when using standard flattening and calibration techniques involving single flat-field exposures and mid-level exposures of standard sources for calibration. Furthermore, the useful dynamic range of the device must be restricted to achieve even this precision, since deviations from linearity are greatest at higher exposure levels. We describe a technique to digitally linearize NICMOS-3 images by interpolating within the characteristic response curve for each pixel as determined from a series of exposures of a fiat screen. Using astronomical observations, we quantify the improvements that can be achieved in final photometric precision and useful dynamic range. C1 USN, Observ Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Luginbuhl, CB (reprint author), USN, Observ Flagstaff Stn, Flagstaff, AZ 86002 USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2801-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3354 BP 240 EP 246 DI 10.1117/12.317305 PN 1-2 PG 7 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BL60J UT WOS:000075982700026 ER PT S AU Scribner, D Schuler, J Warren, P Satyshur, M Kruer, M AF Scribner, D Schuler, J Warren, P Satyshur, M Kruer, M BE Dereniak, EL Sampson, RE TI Infrared color vision: Separating objects from backgrounds SO INFRARED DETECTORS AND FOCAL PLANE ARRAYS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Detectors and Focal Plane Arrays V CY APR 14-17, 1998 CL ORLANDO, FL SP SPIE DE sensor fusion; infrared; color discrimination AB The concept of multi-band infrared color vision is discussed in terms of combining two or more bands of infrared imagery into a single composite color image. This work is motivated by emerging new technologies in which two or more infrared bands are simultaneously imaged for improved discrimination of objects from backgrounds. One of the current objectives of this work is to quantify the improvement obtained over single band infrared imagery to detect dim targets in clutter. Methods are discussed for mapping raw image data into an appropriate color space and then processing it to achieve an intuitively meaningful color display for a human viewer. In this regard, the final imagery should provide good color contrast between objects and backgrounds and consistent colors regardless of environmental conditions such as solar illumination and variations in surface temperature. Initial performance measures show that infrared color can improve discrimination significantly over single band imaging. C1 USN, Res Lab, Washington, DC 20375 USA. RP Scribner, D (reprint author), USN, Res Lab, Code 5636, Washington, DC 20375 USA. NR 0 TC 13 Z9 13 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2828-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3379 BP 2 EP 13 DI 10.1117/12.317576 PG 12 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics; Imaging Science & Photographic Technology SC Engineering; Remote Sensing; Optics; Imaging Science & Photographic Technology GA BL57H UT WOS:000075913800001 ER PT S AU Shen, CN Donn, M AF Shen, CN Donn, M BE Holst, GC TI Flight evaluation of advanced third generation midwave infrared sensor SO INFRARED IMAGING SYSTEMS: DESIGN, ANALYSIS, MODELING, AND TESTING IX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Imaging System - Design, Analysis, Modeling, and Testing IX CY APR 15-16, 1998 CL ORLANDO, FL SP SPIE DE staring FPA; infrared; MRTD; MWIR AB In FY-97 the Counter Drug Optical Upgrade (CDOU) demonstration program was initiated by the Program Executive Office for Counter Drug to increase the detection and classification ranges of P-3 counter drug aircraft by using advanced staring infrared sensors. The demonstration hardware is a "pin-for-pin" replacement of the AAS-36 Infrared Detection Set (IRDS) located under the nose radome of a P-3 aircraft. The hardware consists of a 3rd generation mid-wave infrared (MWIR) sensor integrated into a three axis-stabilized turret. The sensor, when installed on the P-3, has a hemispheric field of regard (FOR) and analysis has shown it will be capable of detecting and classifying Suspected Drug Trafficking Aircraft and Vessels (SDTV/SDTA) at ranges several factors over the current IRDS. This paper will discuss the CDOU system and it's lab, ground, and flight evaluation results. Test targets included target templates, range targets, dedicated target boats, and targets of opportunity at the Naval Air Warfare Center Aircraft Division (NAWCAD) and at operational test sites. The objectives of these tests were to: (i) Validate the integration concept of the CDOU package into the P-3 aircraft. (ii) Validate the end-to-end functionality of the system, including sensor/turret controls and recording of imagery during flight. (iii) Evaluate the system sensitivity and resolution on a set of verified resolution targets templates. (iv) Validate the ability of the 3rd generation MWIR sensor to detect and classify targets at a significantly increased range. C1 USN, Air Warfare Ctr, Div Aircraft, Patuxent River, MD 20670 USA. RP Shen, CN (reprint author), USN, Air Warfare Ctr, Div Aircraft, Patuxent River, MD 20670 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2826-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3377 BP 31 EP 40 DI 10.1117/12.319384 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL61D UT WOS:000076007800004 ER PT S AU Wilson, T Davis, C AF Wilson, T Davis, C BE Strojnik, M Andresen, BF TI Hyperspectral Remote Sensing Technology (HRST) program and the Naval EarthMap Observer (NEMO) satellite SO INFRARED SPACEBORNE REMOTE SENSING VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Infrared Spaceborne Remote Sensing VI CY JUL 22-24, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE imaging spectrometry; optical remote sensing; hyperspectral sensing; on-board processing ID AVIRIS DATA; REFLECTANCE AB The Office of Naval Research (ONR) and the Naval Research Laboratory (NRL) are currently in the design phase of a program called the Hyperspectral Remote Sensing Technology (HRST) program. HRST will demonstrate the utility of a hyperspectral earth-imaging system to support Naval needs for characterization of the littoral regions of the world. One key component of the HRST program is the development of the Naval EarthMap Observer (NEMO) satellite system to provide a large hyperspectral data base. NEMO will carry the Coastal Ocean imaging Spectrometer (COIS) which will provide images of littoral regions with 210 spectral channels over a bandpass of 0.4 to 2.5 mu m Since ocean environments have reflectances typically less than 5%, this system requires a very high signal-to-noise ratio (SNR). COIS will sample over a 30 km swath width with a 60 m Ground Sample Distance (GSD) with the ability to go to a 30 m GSD by utilizing the systems attitude control system to "nod" (i.e., use ground motion compensation to slow down the ground track of the field of view). Also included in the payload is a co-registered 5m Panchromatic Imager (PIC) to provide simultaneous high spatial resolution imagery. A sun-synchronous circular orbit of 605 km allows continuous repeat coverage of the whole earth. One unique aspect of NEMO is an on board processing system, a feature extraction and data compression software package developed by NRL called the Optical Real-Time Spectral identification System (ORASIS). ORASIS employs a parallel, adaptive hyperspectral method for real time scene characterization, data reduction, background suppression, and target recognition. The use of ORASIS is essential for management of the massive amounts of data expected from the NEMO HSI system, and for developing Naval products under HRST. The combined HSI and panchromatic images will provide critical phenomenology to aid in the operation of Naval systems in the littoral environment. The imagery can also satisfy a number of commercial and science community requirements for moderate spatial and high spectral resolution remote sensing data over land and water. Specific areas of interest for the. Navy include bathymetry, water clarity, bottom type, atmospheric visibility, bioluminescence potential, beach characterization, underwater hazards, total column atmospheric water vapor, and detection and mapping of subvisible cirrus. These data support requirements for Joint Strike and Joint Littoral warfare, particularly for environmental characterization of the littoral ocean. Demonstrations of timely downlinks of near real-time data to the warfighter are also being formulated. The NEMO satellite is planned to launch in mid-2000 followed by an operational period of 3 to 5 years. C1 Off Naval Res, Arlington, VA 22217 USA. RP Wilson, T (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 14 TC 7 Z9 7 U1 0 U2 8 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2892-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3437 BP 2 EP 10 DI 10.1117/12.331328 PG 9 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM32P UT WOS:000078391700001 ER PT S AU Davis, CO Kappus, M Gao, BC Bissett, WP Snyder, W AF Davis, CO Kappus, M Gao, BC Bissett, WP Snyder, W BE Strojnik, M Andresen, BF TI The Naval EarthMap Observer (NEMO) science and naval products SO INFRARED SPACEBORNE REMOTE SENSING VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Infrared Spaceborne Remote Sensing VI CY JUL 22-24, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE coastal; imaging spectrometry; oceanography; optical remote sensing; hyperspectral imaging ID REMOTE-SENSING REFLECTANCE; AVIRIS DATA; ALGORITHM; AIRBORNE; IMAGERY AB A wide variety of applications of imaging spectrometry have been demonstrated using data from aircraft systems. Based on this experience the Navy is pursuing the Hyperspectral Remote Sensing Technology (HRST) Program to use hyperspectral imagery to characterize the littoral environment, for scientific and environmental studies and to meet Naval needs. To obtain the required space based hyperspectral imagery the Navy has joined in a partnership with industry to build and fly the Naval EarthMap Observer(NEMO). The NEMO spacecraft has the Coastal Ocean Imaging Spectrometer (COIS) a hyperspectral imager with adequate spectral and spatial resolution and a high signal-to-noise ratio to provide long term monitoring and real-time characterization of the coastal environment. It includes on-board processing for rapid data analysis and data compression, a large volume recorder, and high speed downlink to handle the required large volumes of data. This paper describes the algorithms for processing the COIS data to provide at-launch ocean data products, and the research and modeling that are planned to use COIS data to advance our understanding of the dynamics of the coastal ocean. C1 USN, Res Lab, Washington, DC 20375 USA. RP Davis, CO (reprint author), USN, Res Lab, Code 7212, Washington, DC 20375 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2892-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3437 BP 11 EP 19 DI 10.1117/12.331329 PG 9 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM32P UT WOS:000078391700002 ER PT S AU Bowles, J Antoniades, J Skibo, J Daniel, M Haas, D Grossmann, J Baumback, M AF Bowles, J Antoniades, J Skibo, J Daniel, M Haas, D Grossmann, J Baumback, M BE Strojnik, M Andresen, BF TI On-board hyperspectral compression and analysis system for the NEMO satellite SO INFRARED SPACEBORNE REMOTE SENSING VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Infrared Spaceborne Remote Sensing VI CY JUL 22-24, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE hyperspectral; real-time processing; data compression; visible; infrared; remote sensing; satellite AB The primary mission of the Naval EarthMap Observer (NEMO) is to demonstrate the importance of hyperspectral imagery in characterizing the littoral battlespace environment and littoral model development. NEMO will demonstrate real time on-board processing and compression of hyperspectral data with real-time tactical downlink of ocean and surveillance products directly from the spacecraft to the field. The NRL's Optical Real-time Adaptive Spectral Identification System (ORASIS) will be deployed on a 3.8 Gflop multiprocessing computer, the Imagery On-Board Processor (IOBP), for automated data analysis, feature extraction and compression. NEMO's wide area coverage (10(6) km(2) imaged per day), as well as power and cost constraints require data compression between 10:1 and 20:1. The NEMO Sensor Imaging Payload (SIP) consists of two primary sensors: first, the Coastal Ocean Imaging Spectrograph (COIS) is a hyperspectral imager which records 60 spectral bands in the VNIR (400 to 1000 nm) and 150 bands in the SWIR (1000 to 2500 nm), with a GSD of either 30 or 60 meters; and second, the 5 m GSD Panchromatic Imaging Camera (PIC). This paper describes the design and implementation of the data processing hardware and software for the NEMO satellite. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Bowles, J (reprint author), USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2892-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3437 BP 20 EP 28 DI 10.1117/12.331330 PG 9 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM32P UT WOS:000078391700003 ER PT B AU Merritt, RG AF Merritt, RG GP IES TI Transient vibration, pulse method and the product model SO INSTITUTE OF ENVIRONMENTAL SCIENCES AND TECHNOLOGY - 1998 PROCEEDINGS: DESIGN, TEST, AND EVALUATION PRODUCT RELIABILITY LA English DT Proceedings Paper CT 44th Annual Technical Meeting of the Institute-of-Environmental-Sciences-and-Technology on the 21st Century - A New Frontier in International Information Exchange CY APR 26-MAY 01, 1998 CL PHOENIX, AZ SP Inst Environm Sci & Technol DE transient vibration; pulse method; product model; stationary; cyclostationary AB This paper provides guidance for practical consideration and implementation of short time-varying environments termed "transient vibration" and "pulse method" in MIL-STD-810F. Transient vibration is introduced in Method 514 Vibration in MIL-STD-810F as a means of testing components to short bursts of high level random vibration. The pulse method is introduced in Method 519 Gunfire of MIL-STD-810F as a means of laboratory test replication that may provide better representation of in service gunfire environments. C1 USN, Air Warfare Ctr, Weap Div, Environm Engn Sect, China Lake, CA 93555 USA. RP Merritt, RG (reprint author), USN, Air Warfare Ctr, Weap Div, Environm Engn Sect, Commander Code 473140D-MS 223D, China Lake, CA 93555 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INST ENVIRONMENTAL SCIENCES PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 USA BN 1-877862-63-0 PY 1998 BP 43 EP 54 PG 4 WC Acoustics; Environmental Sciences; Instruments & Instrumentation SC Acoustics; Environmental Sciences & Ecology; Instruments & Instrumentation GA BL14X UT WOS:000074492400007 ER PT J AU Samaddar, SN AF Samaddar, SN TI Some integrals associated with diffraction of single-cycle sinusoids by a circular conducting disk SO INTEGRAL TRANSFORMS AND SPECIAL FUNCTIONS LA English DT Article DE Bessel-function integrals; Hankel-function integrals AB Evaluations of some uncommon integrals involving Bessel and Hankel functions are presented in closed form. These integrals appear in expressions for an electromagnetic or acoustic field and for the energy density in the Fresnel region of a conducting circular disk excited by single-cycle sinusoids. C1 USN, Res Lab, Washington, DC 20375 USA. RP Samaddar, SN (reprint author), USN, Res Lab, Code 5340,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1065-2469 J9 INTEGR TRANSF SPEC F JI Integral Transform. Spec. Funct. PY 1998 VL 7 IS 1-2 BP 113 EP 122 DI 10.1080/10652469808819190 PG 10 WC Mathematics, Applied; Mathematics SC Mathematics GA 139CQ UT WOS:000077010500010 ER PT J AU Horwitz, JS Chang, W Carter, AC Pond, JM Kirchoefer, SW Chrisey, DB Levy, J Hubert, C AF Horwitz, JS Chang, W Carter, AC Pond, JM Kirchoefer, SW Chrisey, DB Levy, J Hubert, C TI Structure/property relationships in ferroelectric thin films for frequency agile microwave electronics SO INTEGRATED FERROELECTRICS LA English DT Article DE Ba0.5Sr0.5TiO3; tunable microwave devices; pulsed laser deposition AB Ferroelectric thin films, deposited by pulsed laser deposition (PLD), are currently being used to develop a new class of tunable microwave circuits based on the electric field dependence of the dielectric constant. Single phase, (100) oriented Ba0.5Sr0.5TiO3 (BST) films have been deposited onto (100) LaAlO3, SrTiO3, and MgO substrates. Interdigitated capacitors patterned on top of the ferroelectric film have been used to measure the dielectric constant and dissipation factor of these films as a function of DC bias and temperature at 1 MHz and as a function of DC bias and frequency (1 to 20 GHz) at room temperature. The dielectric properties of the ferroelectric film is sensitive to both the deposition and post processing conditions. Optical imaging of the ferroelectric films using confocal scanning optical microscopy (CSOM) shows reproducible polarization fluctuations over sub-micrometer length scales for BST films deposited onto SrTiO3 which are not observed for films deposited onto MgO. Dielectric loss in the ferroelectric film is reduced through a combination of post deposition processing and donor/acceptor doping of the films. The lowest dielectric loss measured has been tan delta = 0.01 - 0.005. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Pittsburgh, Pittsburgh, PA 15260 USA. RP Horwitz, JS (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Levy, Jeremy/A-2081-2009 OI Levy, Jeremy/0000-0002-5700-2977 NR 10 TC 24 Z9 25 U1 0 U2 3 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1998 VL 22 IS 1-4 BP 799 EP 809 PG 11 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 130WX UT WOS:000076544300027 ER PT J AU Rao, JBL Patel, DP Sengupta, LC AF Rao, JBL Patel, DP Sengupta, LC TI Phased array antennas based on bulk phase shifting with ferroelectrics SO INTEGRATED FERROELECTRICS LA English DT Article DE bulk phase shifting; ferroelectric materials/devices; lens antennas; phased array antennas; phase shifters ID SHIFTERS AB A new concept for phased arrays is proposed using a voltage controlled ferroelectric lens. The ferroelectric lens concept uniquely incorporates bulk phase shifting; the array does not contain individual phase shifters but rather uses ferroelectric material. This will reduce the number of phase shifters from (n x m) to (n + m), where n is the number of columns and m is the number of rows in a phased array. The number of phase shifter drivers and phase shifter controls is also significantly reduced by using row-column beam steering. Thus, the ferroelectric lens concept can potentially lead to low-cost phased arrays. This paper presents the ferroelectric lens concept, theoretical analysis and design, and experimental results. A brief discussion of ferroelectric materials is also included. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. USA, Res Lab, Mat Directorate, Aberdeen Proving Ground, MD 21005 USA. RP Rao, JBL (reprint author), USN, Res Lab, Div Radar, Washington, DC 20375 USA. NR 12 TC 8 Z9 8 U1 0 U2 1 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1998 VL 22 IS 1-4 BP 827 EP 836 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 130WX UT WOS:000076544300029 ER PT J AU Pond, JM Kirchoefer, SW Chang, W Horwitz, JS Chrisey, DB AF Pond, JM Kirchoefer, SW Chang, W Horwitz, JS Chrisey, DB TI Microwave properties of ferroelectric thin films SO INTEGRATED FERROELECTRICS LA English DT Article DE ferroelectric; varactor; interdigitated capacitor ID PULSED-LASER DEPOSITION; CAPACITORS AB The microwave properties of ferroelectric thin films are being investigated. Interdigitated capacitors fabricated on ferroelectric thin films of Sr0.5Ba0.5TiO3 have been characterized at room temperature from 50 MHz to 20 GHz, The relative dielectric constant and dielectric loss tangent of the ferroelectric thin film are then extracted using a conformal-mapping based approach. For large dielectric constants the upper frequency limit for which the conformal-mapping technique is valid can be as low as 5 GHz. This information is being used to optimize the ferroelectric film deposition process for microwave device application. Results indicate that this technology will compare favorably with conventional varactors above a few GHz, and should be useful for tunable microwave circuits in some 300 K applications. C1 USN, Res Lab, Washington, DC 20375 USA. RP Pond, JM (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 8 TC 6 Z9 7 U1 0 U2 4 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1998 VL 22 IS 1-4 BP 837 EP 848 PG 12 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 130WX UT WOS:000076544300030 ER PT S AU Godbole, DN Sengupta, R Misener, J Kourjanskaia, N Michael, JB AF Godbole, DN Sengupta, R Misener, J Kourjanskaia, N Michael, JB GP NATL RES COUNCIL TI Benefit evaluation of crash avoidance systems SO INTELLIGENT TRANSPORTATION SYSTEMS: ADVANCED TRAVELER INFORMATION SYSTEMS AND SAFETY RESEARCH SE TRANSPORTATION RESEARCH RECORD LA English DT Article; Proceedings Paper CT 77th Annual Meeting of the Transportation-Research-Board CY JAN, 1998 CL WASHINGTON, D.C. SP Transportat Res Board AB A five-layer hierarchy to integrate models, data, and tools is proposed for benefits assessment and requirements development for crash avoidance systems. The framework is known as HARTCAS: Hierarchical Assessment and Requirements Tools for Crash Avoidance Systems. The analysis problem is multifaceted and large-scale. The driving environment is diverse and uncertain, driver behavior and performance are not uniform, and the range of applicable collision avoidance technologies is wide. Considerable real-world data are becoming available on certain aspects of this environment, although the collection of experimental data on other aspects is constrained by technological and institutional issues. Therefore, analyses of collision avoidance systems are to be conducted by collecting data on nominal operating conditions to the greatest extent possible and by using such data to build models for analysis of the rare, abnormal conditions. HARTCAS provides a framework within which to structure the collection and use of such knowledge. It is described in general terms, and its use is illustrated by analysis of a forward collision warning system. How to quantify the relationships between the effectiveness of a warning and the probability that the warning is a nuisance is shown. System benefits are also quantified. C1 Univ Calif Berkeley, Calif Partners Adv Transit & Highways Program, Richmond, CA 94804 USA. USN, Dept Comp Sci, Postgrad Sch, Monterey, CA 93943 USA. RP Godbole, DN (reprint author), Univ Calif Berkeley, Calif Partners Adv Transit & Highways Program, 1357 S 46th St, Richmond, CA 94804 USA. NR 23 TC 1 Z9 1 U1 0 U2 0 PU NATL ACAD SCI PI WASHINGTON PA 2101 CONSTITUTION AVE, WASHINGTON, DC 20418 USA SN 0361-1981 BN 0-309-06466-X J9 TRANSPORT RES REC PY 1998 IS 1621 BP 1 EP 9 PG 9 WC Engineering, Civil; Transportation SC Engineering; Transportation GA BN47W UT WOS:000081981900001 ER PT S AU Zachary, W Cannon-Bowers, J Burns, J Bilazarian, P Krecker, D AF Zachary, W Cannon-Bowers, J Burns, J Bilazarian, P Krecker, D BE Goettl, BP Halff, HM Redfield, CL Shute, VJ TI An Advanced Embedded Training System (AETS) for tactical team training SO INTELLIGENT TUTORING SYSTEMS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 4th International Conference on Intelligent Tutoring Systems (ITS 98) CY AUG 16-19, 1998 CL SAN ANTONIO, TEXAS SP AFRL, Mei Technol, St Marys Univ, Galaxy Scientif Command Technol, Univ Texas San Antonio AB The Advanced Embedded Training System (AETS) applies intelligent tutoring systems technology to improve tactical training quality and reduce manpower needs in simulation-based shipboard team training. AETS provides layers of performance assessment, cognitive diagnosis, and instructor-support on top of the existing embedded mission simulation capability. Detailed cognitive models of trainee task performance are used to drive the assessment, diagnosis and instructional functions of the system. C1 CHI Syst Inc, Lower Gwynedd, PA USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. Sonalysts Inc, Orlando, FL USA. Lockheed Martin Adv Technol Labs, Camden, NJ USA. RP Zachary, W (reprint author), CHI Syst Inc, 716 N Bethlehem Pike,Suite 300, Lower Gwynedd, PA USA. OI Cannon-Bowers, Janis/0000-0003-2154-4456 NR 5 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-64770-8 J9 LECT NOTES COMPUT SC PY 1998 VL 1452 BP 544 EP 553 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Education, Scientific Disciplines SC Computer Science; Education & Educational Research GA BN52L UT WOS:000082115200060 ER PT S AU Schneidewind, NF AF Schneidewind, NF BE Khoshgoftaar, TM Bennett, K TI Methods for assessing COTS reliability, maintainability, and availability SO INTERNATIONAL CONFERENCE ON SOFTWARE MAINTENANCE, PROCEEDINGS SE Proceedings-IEEE International Conference on Software Maintenance LA English DT Proceedings Paper CT International Conference on Software Maintenance CY NOV 16-20, 1998 CL BETHESDA, MD SP IEEE, IEEE Comp Soc Tech Council Software Engn, CRIM Canada, META Grp, Inc C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP USN, Postgrad Sch, Code IS-SS, Monterey, CA 93943 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1063-6773 BN 0-8186-8779-7 J9 PROC IEEE INT CONF S PY 1998 BP 224 EP 225 PG 2 WC Computer Science, Software Engineering SC Computer Science GA BM28W UT WOS:000078275000029 ER PT J AU Griffin, GR AF Griffin, GR TI Predicting naval aviator flight training performance using multiple regression and an artificial neural network SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article AB The potential of a series of automated single-task and multitask tests to account for additional significant variance in the prediction of Navy pilot flight grades was evaluated. Volunteer participants (student naval aviators) were tested on a series of cognitive and perceptual psychomotor tests. The participants then entered the Navy's flight training program at Whiting Field, Florida. Participants' flight grades were obtained at the end of primary training. Multiple-regression and artificial neural network procedures were evaluated to determine their relative efficiency in predicting flight grade training performance. C1 USN, Educ & Training Profess Dev & Technol Ctr, Dept Navy, Pensacola, FL 32509 USA. RP Griffin, GR (reprint author), USN, Educ & Training Profess Dev & Technol Ctr, Dept Navy, 6490 Saufley Field Rd, Pensacola, FL 32509 USA. NR 20 TC 8 Z9 8 U1 1 U2 4 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 1050-8414 J9 INT J AVIAT PSYCHOL JI Int. J. Aviat. Psychol. PY 1998 VL 8 IS 2 BP 121 EP 135 DI 10.1207/s15327108ijap0802_3 PG 15 WC Psychology, Applied SC Psychology GA ZW020 UT WOS:000074365600003 ER PT J AU Salas, E Bowers, CA Prince, C AF Salas, E Bowers, CA Prince, C TI Special issue on simulation and training in aviation SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Editorial Material C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. Univ Cent Florida, Dept Psychol, Orlando, FL 32816 USA. RP Salas, E (reprint author), USN, Air Warfare Ctr, Training Syst Div, Code 4961,12350 Res Pkwy, Orlando, FL 32826 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 1050-8414 J9 INT J AVIAT PSYCHOL JI Int. J. Aviat. Psychol. PY 1998 VL 8 IS 3 BP 195 EP 196 DI 10.1207/s15327108ijap0803_1 PG 2 WC Psychology, Applied SC Psychology GA 104XL UT WOS:000075041800001 ER PT J AU Salas, E Bowers, CA Rhodenizer, L AF Salas, E Bowers, CA Rhodenizer, L TI It is not how much you have but how you use it: Toward a rational use of simulation to support aviation training SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article ID TO-GROUND ATTACK AB One of the most remarkable changes in aviation training over the past few decades is the use of simulation. The capabilities now offered by simulation have created unlimited opportunities for aviation training. In fact, aviation training is now more realistic, safe, cost-effective, and flexible than ever before. However, we believe that a number of misconceptions-or invalid assumptions-exist in the simulation community that prevent us from fully exploiting and utilizing recent scientific advances in a number of related fields in order to further enhance aviation training. These assumptions relate to the overreliance on high-fidelity simulation and to the misuse of simulation to enhance learning of complex skills. The purpose of this article is to discuss these assumptions in the hope of initiating a dialogue between behavioral scientists and engineers. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. Univ Cent Florida, Dept Psychol, Orlando, FL 32816 USA. RP Salas, E (reprint author), USN, Air Warfare Ctr, Training Syst Div, Code 4961,12350 Res Pkwy, Orlando, FL 32826 USA. NR 47 TC 64 Z9 64 U1 4 U2 6 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1050-8414 J9 INT J AVIAT PSYCHOL JI Int. J. Aviat. Psychol. PY 1998 VL 8 IS 3 BP 197 EP 208 DI 10.1207/s15327108ijap0803_2 PG 12 WC Psychology, Applied SC Psychology GA 104XL UT WOS:000075041800002 PM 11541532 ER PT J AU Fowlkes, J Dwyer, DJ Oser, RL Salas, E AF Fowlkes, J Dwyer, DJ Oser, RL Salas, E TI Event-based approach to training (EBAT) SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article AB The importance of providing real-world experience through virtual environments is well accepted, and this mode of training is used extensively in aviation. It is, therefore, surprising that there are few general methods that guide the design of simulation-based training. The lack of such methods is problematic. Due to recent factors in the aviation industry, such as advances in technology, individuals must now possess a range of skills, increasingly cognitive in nature, that must be trained and evaluated through hands-on experience. Second, training is broadening from an almost exclusive focus on individuals and teams to include multiple crews. It is clear that exercise design methodologies are needed. The purpose of this article is to describe a general approach to the design of simulation-based exercises referred to as the Event-Based Approach to Training (EBAT). Event-based techniques guide the design of training opportunities by systematically identifying and introducing events within training exercises that provide known opportunities to observe behaviors of interest. With EBAT, explicit links are maintained between training objectives, exercise design, and performance assessment. We also discuss several recent applications and address potential new areas that may benefit from its application. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. Summit Technol Inc, Orlando, FL USA. RP Salas, E (reprint author), USN, Air Warfare Ctr, Training Syst Div, Code 4961,12350 Res Pkwy, Orlando, FL 32826 USA. NR 22 TC 59 Z9 63 U1 1 U2 3 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1050-8414 J9 INT J AVIAT PSYCHOL JI Int. J. Aviat. Psychol. PY 1998 VL 8 IS 3 BP 209 EP 221 DI 10.1207/s15327108ijap0803_3 PG 13 WC Psychology, Applied SC Psychology GA 104XL UT WOS:000075041800003 ER PT S AU Fisher, J Antoniades, J Rollins, C Xiang, L AF Fisher, J Antoniades, J Rollins, C Xiang, L BE Gardner, LR Thompson, KP TI A hyperspectral imaging sensor for the coastal environment SO INTERNATIONAL OPTICAL DESIGN CONFERENCE 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1998 International Optical Design Conference CY JUN 08-12, 1998 CL KONA, HI SP OSA, Opt Soc Amer, SPIE Int Soc Opt Engn DE imaging spectrograph; hyperspectral; three-mirror anastigmat; and convex holographic gratings; Navy EarthMap Observer Satellite AB Recent advances in large format detector arrays and holographic diffraction gratings have made possible the development of imaging spectrographs with high sensitivity and resolution ideally suited for space-based remote sensing of earth resources. An optical system composed of dual spectrographs and a common fore-optic has been designed for the visible-near infrared (VNIR) and shortwave bands with IO-nm spectral resolution, providing 30-meter ground resolution from an altitude of 605 lan. The spectrograph designs are based on a modified Offner I-X relay with spherical mirrors and a convex spherical holographic grating for the secondary mirror. The fore-optic is a three-mirror anastigmatic telescope with a 360-mm focal length to match the pixel pitch of the respective 1024x1024 visible silicon CCD and SWIR HgCdTe FPAs. The primary advantages of this design are the relatively low f-number (f/3), large flat field (18mm), and low distortion. Preliminary performance results of a VNIR testbed grating and spectrograph are presented and compared to the design predictions. C1 USN, Res Lab, Washington, DC 20375 USA. RP Fisher, J (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 11 Z9 11 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2937-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3482 BP 179 EP 186 DI 10.1117/12.322003 PG 8 WC Optics SC Optics GA BL97D UT WOS:000077312500023 ER PT J AU Boley, D Gini, M Hastings, K Mobasher, B Moore, J AF Boley, D Gini, M Hastings, K Mobasher, B Moore, J TI A client-side Web agent for document categorization SO INTERNET RESEARCH-ELECTRONIC NETWORKING APPLICATIONS AND POLICY LA English DT Article DE agencies; algorithms; customer orientation; information retrieval; information systems; Internet AB The authors propose a client-side agent for exploring and categorizing documents on the World Wide Web. As the user browses the Web using a usual Web browser, this agent is designed to aid the user by classifying the documents the user finds most interesting into clusters. The agent carries out the task completely automatically and autonomously with as little user intervention as the user desires. The principal novel components in this agent that make it possible are a scalable hierarchical clustering algorithm and a taxonomic label generator. In this paper, the overall architecture of this agent is described and the details of the algorithms within its key components are discussed. C1 Univ Minnesota, Dept Comp Engn & Sci, Minneapolis, MN 55455 USA. USN, Washington, DC 20350 USA. Depaul Univ, Dept Comp Sci, Chicago, IL 60604 USA. RP Boley, D (reprint author), Univ Minnesota, Dept Comp Engn & Sci, Minneapolis, MN 55455 USA. OI Gini, Maria/0000-0001-8841-1055 NR 32 TC 3 Z9 3 U1 1 U2 2 PU MCB UNIV PRESS LTD PI BRADFORD PA 60/62 TOLLER LANE, BRADFORD BD8 9BY, W YORKSHIRE, ENGLAND SN 1066-2243 J9 INTERNET RES JI Internet Res.-Electron. Netw. Appl. Policy PY 1998 VL 8 IS 5 BP 387 EP + DI 10.1108/10662249810241257 PG 14 WC Business; Computer Science, Information Systems; Telecommunications SC Business & Economics; Computer Science; Telecommunications GA 148XY UT WOS:000077560700003 ER PT B AU Meyer, JR Vurgaftman, I Olafsen, LJ Aifer, EH Bewley, WW Felix, CL Lin, CH Zhang, D Yang, RQ Pei, SS Vodopyanov, KL O'Neill, K Phillips, CC Hopkinson, M AF Meyer, JR Vurgaftman, I Olafsen, LJ Aifer, EH Bewley, WW Felix, CL Lin, CH Zhang, D Yang, RQ Pei, SS Vodopyanov, KL O'Neill, K Phillips, CC Hopkinson, M BE Li, SS Su, YK TI Phase-matched second-harmonic and cascade laser mid-IR sources SO INTERSUBBAND TRANSITIONS IN QUANTUM WELLS: PHYSICS AND DEVICES LA English DT Proceedings Paper CT International Workshop on Intersubband Transitions in Quantum Wells - Physics and Applications CY DEC 15-18, 1997 CL NATL CHENG KUNG UNIV, TAINAN, TAIWAN SP Natl Sci Council & Minist Educ, Off Naval Res-Asia, US Army Res Off-Far E HO NATL CHENG KUNG UNIV DE mid-IR sources; second harmonic generation; intersubband transitions; lasers; quantum wells ID ASYMMETRIC QUANTUM-WELLS C1 USN, Res Lab, Washington, DC 20375 USA. RP Meyer, JR (reprint author), USN, Res Lab, Code 5613, Washington, DC 20375 USA. NR 16 TC 0 Z9 0 U1 0 U2 2 PU KLUWER ACADEMIC PUBLISHERS PI NORWELL PA 101 PHILIP DRIVE, ASSINIPPI PARK, NORWELL, MA 02061 USA BN 0-7923-8164-5 PY 1998 BP 22 EP 29 PG 8 WC Optics; Physics, Applied; Physics, Multidisciplinary SC Optics; Physics GA BN28B UT WOS:000081415100004 ER PT B AU Pace, PE Styer, D Akin, IA AF Pace, PE Styer, D Akin, IA GP IEEE IEEE TI A folding adc employing a robust symmetrical number system with gray-code properties SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB A folding analog-to-digital converter (ADC) preprocessing design based on a new robust symmetrical number system (RSNS) is presented. The RSNS preprocessing architecture is a modular scheme in which the integer values within each modulus (comparator states), when considered together, change one at a time at the next position (Gray code properties). Although the observed dynamic range of the RSNS ADC is somewhat less than the optimum symmetrical number system ADC, the RSNS Gray code properties make it particularly attractive for error control. With the RSNS preprocessing, the encoding errors due to comparator thresholds not being crossed simultaneously are eliminated. As a result, the interpolation circuits can be removed and only a small number of comparators are required. Computer generated data is used to help determine the properties of the RSNS. These properties include the dynamic range (largest number of distinct consecutive vectors) and the location of the dynamic range within the number system Closed-form expressions for the dynamic range are also presented for channel moduli of the form m(1) = 2(k) - 1, m(2) = 2(k),m(3) = 2(k) + 1. To compare the advantages of the RSNS ADC with previously published results, the transfer function of a 3-channel architecture (k=2) is evaluated numerically using SPICE. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Pace, PE (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Code EC-PC, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP 397 EP 400 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600100 ER PT B AU Davis, AJ Fischer, G AF Davis, AJ Fischer, G GP IEEE IEEE TI Digital correction of non-ideal amplifier effects in the MASH modulator SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB An approach to remove the effects of amplifier finite gain and C-ratio mismatches in the MASH sigma-delta modulator is presented. By adding a digital correction term to the output of the digital noise cancellation filter, the parasitic quantization noise terms can be removed for all but the final stage, eliminating the intermediate quantization noise terms due to non-ideal integrators. Using this technique, the MASH can approach the performance of an ideal third-order modulator. We have confirmed an SNR+THD of 105.6 dB via a behavioral simulation of the MASH using an amplifier open-loop gain of only 500 and capacitor matching errors as large as of 1.0 %. C1 USN, Undersea Warfare Ctr, Weap Syst Dept, Newport, RI 02841 USA. RP Davis, AJ (reprint author), USN, Undersea Warfare Ctr, Weap Syst Dept, Newport, RI 02841 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP 600 EP 603 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600151 ER PT B AU Pace, PE Styer, D Ringer, WP AF Pace, PE Styer, D Ringer, WP GP IEEE IEEE TI Optimum SNS to binary conversion algorithm and FPGA realization SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB Folding analog-to-digital converters, fold the input signal symmetrically in order to reduce the number of comparators required to amplitude analyze the signal (preprocessing). The optimum symmetrical number system (OSNS) formulation is a direct consequence of the need to extract the maximum amount of information from a symmetrically folded waveform OSNS folding converters require the minimum number of comparator circuits for any desired resolution. Although there is a direct correspondence between the OSNS and the residue number system, the symmetrical residues cannot be converted to a binary value (e.g., using the Chinese Remainder Theorem) in a straightforward manner. This paper presents an efficient algorithm that converts the symmetrical residues within a three moduli (2(k) + 1, 2(k),2(k) -1) OSNS to the equivalent binary representation. Also presented is a pipelined field programmable gate array (FPGA) realization of the algorithm. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Pace, PE (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Code EC-Pc, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP A224 EP A227 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600208 ER PT B AU Ashton, RW Ciezki, JG Mak, C AF Ashton, RW Ciezki, JG Mak, C GP IEEE IEEE TI The formulation and implementation of an analog/digital control system for a 100kW DC-to-DC buck chopper SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB The authors present a description of the design and implementation of an analog/digital controller for a 100kW Ship Service Converter Module that is being used in a reduced-scale DC Zonal Electric Distribution System. The system requirements, control law, controller modes of operation and validation studies are documented. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Ashton, RW (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B489 EP B492 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600395 ER PT B AU Ashton, RW Ciezki, JG AF Ashton, RW Ciezki, JG GP IEEE IEEE TI Feedback gains for a DC distribution system DC-to-DC converter SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB The authors present a robust algorithm for controlling buck choppers that includes feedforward and droop. Averaged and detailed simulation models are used to optimize the design of the buck output capacitance and the feedback gains. In particular, an effort was made to simultaneously minimize voltage ripple and control effort while avoiding sustained oscillations in the duty cycle. The final design is tested using a prototype 9kW chopper supplying a wide variety of loads including constant power loads. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Ashton, RW (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B387 EP B390 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600370 ER PT B AU Ashton, RW Ciezki, JG AF Ashton, RW Ciezki, JG GP IEEE IEEE TI The design and fabrication of a reconfigurable hardware testbed for the interaction analysis of power converters in a reduced-scale Navy DC distribution system SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB The authors present a reconfigurable de distribution testbed that contains a number of converters, inverters and adjustable link impedances. The purpose of the hardware testbed is to study the interaction between nonlinear high-bandwidth converters in order to establish a means to develop theoretical stability criteria. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Ashton, RW (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B379 EP B382 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600368 ER PT B AU Ciezki, JG Ashton, RW AF Ciezki, JG Ashton, RW GP IEEE IEEE TI The application of feedback linearization techniques to the stabilization of DC-to-DC converters with constant power loads SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB The authors have devised a nonlinear coordinate transformation for a de-to-de buck chopper supplying a constant power load that facilitates pseudolinearization via a nonlinear feedback. A representative design is introduced and detailed simulation validation studies are presented. The extension of the region of local asymptotic stability is confirmed through Lyapunov analysis. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Ciezki, JG (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B526 EP B529 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600404 ER PT B AU Ciezki, JG Ashton, RW AF Ciezki, JG Ashton, RW GP IEEE IEEE TI In the simulation of finite-inertia power systems SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB The move toward incorporating more-electric technology into naval combatant shipboard power systems and the requisite analysis of such systems have driven the development of accurate detailed simulation strategies for stimy-connected, finite-inertia networks. Since typical bus loads including electric machines are described by voltage-in current-out models, the resultant algebraic loop must be resolved by either inserting artificial components into the network or by reformulating the component models. The authors introduce an alternative algebraic solver approach that obviates the need for developing complex nonstandard component representations and eliminates the tradeoff between speed and accuracy inherent to the artificial component approach. Using a standard simulation package and a representative portion of a shipboard power system, the authors then contrast their approach with two methods commonly reported on in the literature. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Ciezki, JG (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B342 EP B345 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600359 ER PT B AU Curran, E Wooten, K Newcomb, RW AF Curran, E Wooten, K Newcomb, RW GP IEEE IEEE TI An artificial model for biological computation and control for a locomotion system SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB Each discipline has its own methods of modeling its components and developing the mathematical analysis of the systems which they want to describe. Investigating these systems from different perspectives can provide a means of discovering system operation. Specifically, when approaching the reverse engineering of a biological system, the best description of the elements should include the biological parameters and their known relationships. The modeling should be carefully tied to the biological experimental data and the results of the simulations should provide outputs comparable with actual output data from the original system. Once the model has been thoroughly tested, the mathematical description of the model can be redefined with new variables of interest for the discipline involved. This paper describes the design of a neural network capable of providing simulated output comparable to the deafferented flight neural control behavior of the locust, using GENESIS (General Neural Simulation System). [1] C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. RP Curran, E (reprint author), USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B175 EP B178 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600318 ER PT B AU Fitch, O Kang, W AF Fitch, O Kang, W GP IEEE IEEE TI Stabilization of a class of bifurcations via state feedback SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB This paper presents a general method for the control or stabilization of the class of local bifurcations commonly occurring in engineering systems, such as saddle-node, transcritical, pitchfork and Hopf bifurcations. The method presented shows that the problem can be solved by transforming the system into its quadratic normal form, a simplified system with equivalent dynamics, and then examining the resulting dynamics on the center manifold of the system. The dynamics on the center manifold can then be altered by linear and quadratic state feedback of the center states. The feedback gains required are given by simple algebraic combinations of the coefficients of the quadratic normal form. C1 NAVAIR, NAS Patuxent River, MD 20670 USA. RP Fitch, O (reprint author), NAVAIR, Code Air 4-5T, NAS Patuxent River, MD 20670 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B631 EP B634 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600430 ER PT B AU Sellami, L Zaghloul, ME Newcomb, RW AF Sellami, L Zaghloul, ME Newcomb, RW GP IEEE IEEE TI VLSI chaotic pulse coded modulator using neural type cells SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB A means of modulating information signals in both additive and multiplicative ways by chaotic signals is considered. The chaotic signals are obtained from neural type cells set to their chaotic oscillation mode. The information containing signals are modulated by these chaotic signals by introducing each as the input to a differential pair. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. RP Sellami, L (reprint author), USN Acad, Dept Elect Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP B21 EP B24 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600280 ER PT B AU Carroll, TL Johnson, GA AF Carroll, TL Johnson, GA GP IEEE IEEE TI Synchronizing autonomous chaotic circuits using bandpass filtered signals SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB The same broad-band properties that make chaos interesting as a potential communications carrier also cause trouble when chaotic signals are transmitted through real communications channels. Phase and amplitude distortion of a chaotic signal can ruin the ability of a chaotic receiver to synchronize to an incoming chaotic signal. We show that it is possible to use narrow band filters with the chaotic signal to reduce its bandwidth, decreasing the effects of channel distortion, and still synchronize a chaotic receiver to the incoming chaotic signal. C1 USN, Res Lab, Washington, DC 20375 USA. RP Carroll, TL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP C558 EP C561 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600580 ER PT B AU Coffman, JW McEachen, JC AF Coffman, JW McEachen, JC GP IEEE IEEE TI A paradigm for collaboration across a globally networked environment: Implementation of ISCAS'98 Internet services SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB Using current internet technology, an interactive and automated system can be developed to replace traditional aspects of professional and scientific conference organization - particularly those related to receiving, processing, distributing, reviewing and scheduling papers submitted for conference presentations. A two-stage prototype was developed and used for the 1998 IEEE International Symposium on Circuits and Systems (ISCAS '98) to demonstrate and evaluate the effectiveness of this methodology. The initial prototype was used to collect and process the preliminary extended summaries, as well as facilitate the review and scheduling processes. A follow-on prototype was developed for the final camera-ready submissions based on evaluation results of the initial prototype. A comparison of both prototypes and an analysis of their effectiveness is presented. C1 USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. RP Coffman, JW (reprint author), USN, Postgrad Sch, Dept Syst Management, 833 Dyer Rd,Room 437,Code EC-MJ, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP C33 EP C36 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600449 ER PT B AU Pecora, LM Carroll, TL AF Pecora, LM Carroll, TL GP IEEE IEEE TI Master stability functions for synchronized chaos in arrays of oscillators SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB We show that many coupled oscillator array configurations considered in the literature can be put into a simple form so that determining the stability of the synchronous state can be done by a master stability function which solves, once and for all, the problem of synchronous stability for any linear coupling of that oscillator. C1 USN, Res Lab, Washington, DC 20375 USA. RP Pecora, LM (reprint author), USN, Res Lab, Code 6343, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP C562 EP C567 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600581 ER PT B AU Jenn, DC Vitale, RL AF Jenn, DC Vitale, RL GP IEEE IEEE TI Wireless power transfer for a micro remotely piloted vehicle SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB A prototype rectifying antenna (rectenna) to provide wireless power transfer (WPT) to a micro-remotely piloted vehicle (MRPV) is developed. Microwave radiation at 1.3 GHz is converted into DC to drive a small motor and spin a mockup helicopter rotor blade. The rectenna serves a dual purpose as the antenna and outer body of the proposed vehicle and allows efficient reception of power over 360 degrees around the vehicle. Wireless power transfer to the mockup MRPV has been demonstrated with less than 1 watt of transmitted power at near field ranges. Rectification efficiencies up to 30% were measured for two rectifier circuit configurations using 1.3 GHz continuous wave (CW) and pulse modulated transmitted signals. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Jenn, DC (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, 833 Dyer Rd,Code EC Jn, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP E590 EP E593 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600874 ER PT J AU Pelz, O Hesse, C Tesar, M Coffin, RB Abraham, WR AF Pelz, O Hesse, C Tesar, M Coffin, RB Abraham, WR TI Development of methods to measure carbon isotope ratios of bacterial biomarkers in the environment SO ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES LA English DT Article; Proceedings Paper CT Annual Meeting of Arbeitsgemeinschaft-Stabile-Isotope CY SEP 30-OCT 02, 1996 CL BERLIN, GERMANY SP Arbeitsgemein Stabile Isotope DE aspartic acid; biomarker; carbon 13; chemostat; 4-chlorocatechol; 4-chlorosalicylate; fatty acids; gas chromatography; isotope analysis; mass spectrometry ID AMINO-ACID ENANTIOMERS; STABLE CARBON; ORGANIC-MATTER; MICROBIAL-METABOLISM; ESTUARINE BACTERIA; GAS-CHROMATOGRAPHY; MASS-SPECTROMETRY; FATTY-ACIDS; FOOD WEBS; IDENTIFICATION AB The delta(13)C value of bacterial carbon is an important parameter in microbial ecology for studying the carbon flow within a microbial community and for the identification of ecological important strains involved in the mineralization of certain carbon pools in the environment. In our study, biomarkers were isolated from bacteria from a microbial consortium derived from two chemostats and delta(13)C values were measured. Similar isotope ratios between biomarkers such as fatty acids and outer membrane protein, biomass and substrate were observed. The delta(13)C analyses of outer membrane protein F of Pseudomonas and biomarker fatty acids were combined to follow bacterial assimilation of C-13 labelled 4-chlorocatechol. This new approach was also used in the environment where soil samples were cultivated with different C-13 traced substrates. The isotopic analyses of bacterial biomarkers indicated that carbons of histidine were widely incorporated into bacterial biomarkers, in contrast to 4-chlorocatechol which was less often used as a substrate. Results indicate that by isolating bacterial biomarkers and measuring their delta(13)C values, activities of microbial communities in a complex environmental sample can be determined. This new method has the potential to elucidate individual carbon sources for individual bacterial taxa in microbial ecology. C1 GBF Natl Res Ctr Biotechnol, Div Microbiol, D-38124 Braunschweig, Germany. USN, Res Lab, Washington, DC 20375 USA. RP Abraham, WR (reprint author), GBF Natl Res Ctr Biotechnol, Div Microbiol, Mascheroder Weg 1, D-38124 Braunschweig, Germany. EM WAB@gbf-braunschweig.de NR 36 TC 3 Z9 3 U1 1 U2 9 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1025-6016 J9 ISOT ENVIRON HEALT S JI Isot. Environ. Health Stud. PY 1998 VL 34 IS 1-2 BP 131 EP 144 DI 10.1080/10256019808036364 PG 14 WC Chemistry, Inorganic & Nuclear; Environmental Sciences SC Chemistry; Environmental Sciences & Ecology GA ZC073 UT WOS:000072536800013 ER PT B AU Sarpkaya, T Novak, F AF Sarpkaya, T Novak, F BE Krause, E Gersten, K TI Turbulent vortex breakdown: Experiments in tubes at high Reynolds numbers SO IUTAM SYMPOSIUM ON DYNAMICS OF SLENDER VORTICES SE FLUID MECHANICS AND ITS APPLICATIONS LA English DT Proceedings Paper CT IUTAM Symposium on Dynamics of Slender Vortices CY AUG 31-SEP 03, 1997 CL AACHEN, GERMANY SP Int Union Theoret & Appl Mech, Deutsch Forschungsgemeinsch, Ministerium Wissensch & Forsch Landes Nordrhein Westfalen, Rheinisch Westfalische Tech Hochschule Aachen, Stadt Aachen, USAF European Off Aerosp Res & Dev, Kluwer Acad Publ C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Sarpkaya, T (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 5 Z9 5 U1 0 U2 3 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5041-3 J9 FLUID MEC A PY 1998 VL 44 BP 287 EP 296 PG 10 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA BL21W UT WOS:000074739300024 ER PT J AU Tanabe, S Snitzer, E Cole, B AF Tanabe, S Snitzer, E Cole, B TI Blue upconversion characteristics of thulium-doped silica fiber with high germania content SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT International Workshop on Structure and Functional Optical Properties of Silica and Silica-Related Glasses CY JUL 10-11, 1997 CL TOYOTA MOTOR CORP, MIKKABI CREAT CTR, SHIZUOKA, JAPAN SP US Govt HO TOYOTA MOTOR CORP, MIKKABI CREAT CTR DE upconversion; optical fiber; blue laser; rare-earth; thulium; silica ID LASER; UV AB Intense blue upconversion luminescences were observed in a high-NA silica fiber doped with Tm3+ and 25mol% GeO2 by pumping with a 630-670nm laser. The intensities of two bands due to the (1)D2 --> (3)F4 at 455nm and (1)G4 --> (3)H6 transition at 480nm were changed with the pumping wavelength, power, and the fiber length. These phenomena were ascribed to the population inversion of the (3)F4 excited state to the ground state and large population of the (3)H4, that are the intermediate excited levels for the (1)G4 and (3)D2 upconversions, respectively. The nonlinear power dependence of the population could be due to the relatively low-phonon-energy, high Tm3+-concentration and high pump-power density in the core of this high-NA fiber. The peak shift of the 480nm-band with the fiber length and a two-photon process of 1.2 mu m luminescence band are also discussed. C1 Rutgers State Univ, Fiber Opt Mat Res Program, Piscataway, NJ 08855 USA. USN, Div Opt Sci, Res Lab, Washington, DC 20375 USA. RP Tanabe, S (reprint author), Kyoto Univ, Fac Integrated Studies, Kyoto 60601, Japan. NR 12 TC 4 Z9 4 U1 0 U2 2 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1998 VL 37 SU 1 BP 81 EP 83 PG 3 WC Physics, Applied SC Physics GA ZP235 UT WOS:000073731500024 ER PT B AU Perzanowski, D Schultz, AC Adams, W AF Perzanowski, D Schultz, AC Adams, W GP IEEE TI Integrating natural language and gesture in a robotics domain SO JOINT CONFERENCE ON THE SCIENCE AND TECHNOLOGY OF INTELLIGENT SYSTEMS LA English DT Proceedings Paper CT Joint Conference on the Science and Technology of Intelligent Systems ISIC/CIRA/ISAS CY SEP 14-17, 1998 CL NATL INST STAND & TECHNOL, GAITHERSBURG, MD SP IEEE, Control Syst Soc, Natl Sci Fdn, USA, Army Res Off HO NATL INST STAND & TECHNOL DE biomimetics; gesture; human-computer interfaces; natural language; robotics AB Human-computer interfaces facilitate communication, assist in the exchange of information, process commands and controls, among many additional interactions. For our work in the robotics domain, we have concentrated on integrating spoken natural language and natural gesture for command and control of a semiautonomous mobile robot. We have assumed that both spoken natural language and natural gesture are more user-friendly means of interacting with a mobile robot, and from the human standpoint, such interactions are easier, given that the human is not required to learn additional interactions, but can rely on "natural" ways of communication. So-called "synthetic" methods, such as data gloves, require additional learning; however, this is not the case with natural language and natural gesture. We, therefore, rely on what is natural to both spoken language when it is used in conjunction with natural gestures for giving commands. Furthermore, we have been integrating these interactions with the robotics components as the robotics system is being developed. The interface is not treated as an ad hoc add-on or patch. By doing so, we believe the interface will be more robust and because it is being integrated during system development, we hope to achieve a more seamless interface, one which both acts and feels as an integral part of the robotics application. In this paper, we will discuss the kinds of interactions which our system is currently capable of performing. We will also discuss the processing of the various input to produce an appropriate robotic response. And finally, we will discuss what future kinds of interactions we would like to incorporate into the system, and what will be required to achieve these results. C1 USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. RP Perzanowski, D (reprint author), USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. NR 0 TC 15 Z9 15 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4423-5 PY 1998 BP 247 EP 252 DI 10.1109/ISIC.1998.713669 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL60A UT WOS:000075973800045 ER PT B AU Yamauchi, B Schultz, A Adams, W Graves, K AF Yamauchi, B Schultz, A Adams, W Graves, K GP IEEE TI Integrating map learning, localization and planning in a mobile robot SO JOINT CONFERENCE ON THE SCIENCE AND TECHNOLOGY OF INTELLIGENT SYSTEMS LA English DT Proceedings Paper CT Joint Conference on the Science and Technology of Intelligent Systems ISIC/CIRA/ISAS CY SEP 14-17, 1998 CL NATL INST STAND & TECHNOL, GAITHERSBURG, MD SP IEEE, Control Syst Soc, Natl Sci Fdn, USA, Army Res Off HO NATL INST STAND & TECHNOL DE mobile robotics; map learning; exploration; localization; planning; navigation; multirobot teams AB The major themes of our research include the creation of mobile robot systems that are robust and adaptive in rapidly changing environments and the view of integration as a basic research issue. Where reasonable, we try to use the same representations to allow different components to work more readily together and to allow better and more natural integration of and communication between these components. In this paper, we summarize our recent work in integrated mobile robot exploration, localization, and navigation. C1 USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. RP Yamauchi, B (reprint author), USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. NR 0 TC 6 Z9 6 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4423-5 PY 1998 BP 331 EP 336 DI 10.1109/ISIC.1998.713683 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL60A UT WOS:000075973800059 ER PT B AU Yun, XP Latt, K Glennon, JS AF Yun, XP Latt, K Glennon, JS GP IEEE TI Mobile robot localization using the Hough transform and neural networks SO JOINT CONFERENCE ON THE SCIENCE AND TECHNOLOGY OF INTELLIGENT SYSTEMS LA English DT Proceedings Paper CT Joint Conference on the Science and Technology of Intelligent Systems ISIC/CIRA/ISAS CY SEP 14-17, 1998 CL NATL INST STAND & TECHNOL, GAITHERSBURG, MD SP IEEE, Control Syst Soc, Natl Sci Fdn, USA, Army Res Off HO NATL INST STAND & TECHNOL DE mobile robot; localization; Hough transform; neural networks; sonar AB For an autonomous mobile robot to navigate in an unknown environment, it is essential to know the location of the robot on a real-time basis. Finding position and orientation of a mobile robot in a world coordinate system is a problem in localization. Dead-reckoning as commonly used for localization, but position and orientation errors from dead-reckoning tend to accumulate over time. The objective of this paper is to develop a feature-based localization method that uses the Hough transform to detect wall-like features in the environment based on sonar range data. Although the Hongh transform is an effective method for detecting lines and curves from noisy data, it has the drawback of being sensitive to discretization resolution. Results of line detection using various discretization resolutions and using a winner-take-all neural network are presented and discussed. The results indicate that the Hough transform method is abbe to reliably recognize wall-like features from noisy sonar data, but the accuracy of detected features is dependent heavily on the choice of resolution of parameter discretization. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Yun, XP (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. NR 0 TC 6 Z9 6 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4423-5 PY 1998 BP 393 EP 400 DI 10.1109/ISIC.1998.713694 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL60A UT WOS:000075973800070 ER PT B AU Baggenstoss, PM AF Baggenstoss, PM GP IEEE TI Class-specific feature sets in classification SO JOINT CONFERENCE ON THE SCIENCE AND TECHNOLOGY OF INTELLIGENT SYSTEMS LA English DT Proceedings Paper CT Joint Conference on the Science and Technology of Intelligent Systems ISIC/CIRA/ISAS CY SEP 14-17, 1998 CL NATL INST STAND & TECHNOL, GAITHERSBURG, MD SP IEEE, Control Syst Soc, Natl Sci Fdn, USA, Army Res Off HO NATL INST STAND & TECHNOL AB The classical Bayesian approach to classification requires knowledge of the probability density function (PDF) of the data or sufficient statistic under all class hypotheses. Because it is difficult or impossible to obtain a single low-dimensional sufficient statistic, it is often necessary to utilize a sub-optimal yet still relatively high-dimensional feature set. The performance of such an approach is severely limited by the ability to estimate the PDF on a high-dimensiopnal space from training data. A new theorem shows that by introducing ii special "noise-only" signal class (H0), it is possible to re-formulate the classical approach based upon hi sufficient statistics, one corresponding to each signal class. Furthermore, the optimal classifier requires knowledge of only the PDF's of the sufficient statistics under the corresponding signal class and under noise-only condition. We present simulation results of a 9-class synthetic problem showing dramatic improvements over the traditional high - dimensional approach. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Baggenstoss, PM (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. NR 0 TC 5 Z9 5 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4423-5 PY 1998 BP 413 EP 416 DI 10.1109/ISIC.1998.713697 PG 4 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL60A UT WOS:000075973800073 ER PT B AU Shneier, M AF Shneier, M GP IEEE TI Intelligent Systems at the Office of Naval Research SO JOINT CONFERENCE ON THE SCIENCE AND TECHNOLOGY OF INTELLIGENT SYSTEMS LA English DT Proceedings Paper CT Joint Conference on the Science and Technology of Intelligent Systems ISIC/CIRA/ISAS CY SEP 14-17, 1998 CL NATL INST STAND & TECHNOL, GAITHERSBURG, MD SP IEEE, Control Syst Soc, Natl Sci Fdn, USA, Army Res Off HO NATL INST STAND & TECHNOL DE artificial intelligence; agents; user interface; reasoning; information management; Naval applications AB A brief description is presented of the Intelligent Systems program at the Office of Naval Research. The programs that are currently considered important are described and an indication is given of why the issues are considered important to the Navy. A general view of the status and future of AI is also provided. C1 Off Naval Res, Arlington, VA 22217 USA. RP Shneier, M (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4423-5 PY 1998 BP 888 EP 890 DI 10.1109/ISIC.1998.713837 PG 3 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL60A UT WOS:000075973800154 ER PT J AU Herscovici, DS AF Herscovici, DS TI Minimal paths between maximal chains in finite rank semimodular lattices SO JOURNAL OF ALGEBRAIC COMBINATORICS LA English DT Article DE semimodular lattice; maximal chain; Jordan-Holder permutation; reduced decomposition AB We study paths between maximal chains, or "flags," in finite rank semimodular lattices. Two flags are adjacent if they differ on at most one rank. A path is a sequence of flags in which consecutive flags are adjacent. We study the union of all flags on at least one minimum length path connecting two flags in the lattice. This is a subposet of the original lattice. If the lattice is modular, the subposet is equal to the sublattice generated by the flags. It is a distributive lattice which is determined by the "Jordan-Holder permutation" between the flags. The minimal paths correspond to all reduced decompositions of this permutation. In a semimodular lattice, the subposet is not uniquely determined by the Jordan-Holder permutation for the flags. However, it is a join sublattice of the distributive lattice corresponding to this permutation. It is semimodular, unlike the lattice generated by the two flags, which may not be ranked. The minimal paths correspond to some reduced decompositions of the permutation, though not necessarily all. We classify the possible lattices which can arise in this way, and characterize all possibilities for the set of shortest paths between two flags in a semimodular lattice. C1 St Marys Coll, Dept Math & Comp Sci, Moraga, CA 94575 USA. USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. NR 12 TC 2 Z9 2 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0925-9899 J9 J ALGEBR COMB JI J. Algebr. Comb. PD JAN PY 1998 VL 7 IS 1 BP 17 EP 37 DI 10.1023/A:1008615111070 PG 21 WC Mathematics SC Mathematics GA ZA238 UT WOS:000072343200002 ER PT J AU Herscovici, DS AF Herscovici, DS TI Semimodular lattices and semibuildings SO JOURNAL OF ALGEBRAIC COMBINATORICS LA English DT Article DE semimodular lattice; chamber system; Jordan-Holder permutation AB In a ranked lattice, we consider two maximal chains, or "flags" to be i-adjacent if they are equal except possibly on rank i. Thus, a finite rank lattice is a chamber system. If the lattice is semimodular, as noted in [9], there is a "Jordan-Holder permutation" between any two flags. This permutation has the properties of an S-n-distance function on the chamber system of flags. Using these notions, we define a W-semibuilding as a chamber system with certain additional properties similar to properties Tits used to characterize buildings. We show that finite rank semimodular lattices form an S-n-semibuilding, and develop a flag-based axiomatization of semimodular lattices. We refine these properties to axiomatize geometric, modular and distributive lattices as well, and to reprove Tits' result that S-n-buildings correspond to relatively complemented modular lattices (see [16], Section 6.1.5). C1 St Marys Coll, Dept Math & Comp Sci, Moraga, CA 94757 USA. USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. NR 17 TC 5 Z9 5 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0925-9899 J9 J ALGEBR COMB JI J. Algebr. Comb. PD JAN PY 1998 VL 7 IS 1 BP 39 EP 51 DI 10.1023/A:1008667127908 PG 13 WC Mathematics SC Mathematics GA ZA238 UT WOS:000072343200003 ER PT J AU Lin, FL Woodmansee, D Patterson, R AF Lin, FL Woodmansee, D Patterson, R TI Near-fatal anaphylaxis to topical bacitracin ointment SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Article C1 USN, San Diego Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, San Diego Med Ctr, Dept Internal Med, San Diego, CA 92134 USA. Northwestern Univ, Sch Med, Dept Med, Chicago, IL 60611 USA. RP Lin, FL (reprint author), USN, San Diego Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 8 TC 13 Z9 13 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JAN PY 1998 VL 101 IS 1 BP 136 EP 137 DI 10.1016/S0091-6749(98)70209-X PN 1 PG 2 WC Allergy; Immunology SC Allergy; Immunology GA YR872 UT WOS:000071539800025 PM 9449517 ER PT J AU Kelso, JM Schatz, M AF Kelso, JM Schatz, M TI Astemizole use in pregnancy SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Letter C1 USN, Med Ctr, Dept Internal Med, Div Allergy, San Diego, CA 92134 USA. Kaiser Permanente Med Ctr, Dept Allergy, San Diego, CA 92111 USA. RP Kelso, JM (reprint author), USN, Med Ctr, Dept Internal Med, Div Allergy, San Diego, CA 92134 USA. NR 2 TC 2 Z9 2 U1 1 U2 1 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JAN PY 1998 VL 101 IS 1 BP 144 EP 144 PN 1 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA YR872 UT WOS:000071539800029 PM 9449521 ER PT J AU Kelso, JM Helm, RM Burks, AW AF Kelso, JM Helm, RM Burks, AW TI Common allergens in avian meats. SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 USN, Med Ctr, San Diego, CA 92152 USA. UAMS, Arkansas Childrens Hosp, Little Rock, AR USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JAN PY 1998 VL 101 IS 1 MA 386 BP S92 EP S92 PN 2 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA YW339 UT WOS:000071924800386 ER PT J AU Lin, FL Kelso, JM AF Lin, FL Kelso, JM TI Pulmonary function studies in healthy Filipinos. SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 USN, Med Ctr, San Diego, CA 92152 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JAN PY 1998 VL 101 IS 1 MA 748 BP S182 EP S183 PN 2 PG 2 WC Allergy; Immunology SC Allergy; Immunology GA YW339 UT WOS:000071924800747 ER PT J AU Koubek, E AF Koubek, E TI Acid-base chemistry of the aluminum ion in aqueous solution SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Koubek, E (reprint author), USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 2 TC 4 Z9 4 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD JAN PY 1998 VL 75 IS 1 BP 60 EP 60 PG 1 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA YM871 UT WOS:000071110000027 ER PT J AU Copper, CL Koubek, E AF Copper, CL Koubek, E TI A kinetics experiment to demonstrate the role of a catalyst in a chemical reaction - A versatile exercise for general or physical chemistry students SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article C1 USN Acad, Annapolis, MD 21402 USA. RP Copper, CL (reprint author), USN Acad, 572 Holloway Rd, Annapolis, MD 21402 USA. NR 7 TC 14 Z9 14 U1 1 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD JAN PY 1998 VL 75 IS 1 BP 87 EP 90 PG 4 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA YM871 UT WOS:000071110000042 ER PT J AU Harris, DC AF Harris, DC TI Nonlinear least-squares curve fitting with Microsoft excel solver SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article ID PROGRAM C1 USN, Air Warfare Ctr, Res & Technol Div, Chem & Mat Branch, China Lake, CA 93555 USA. RP Harris, DC (reprint author), USN, Air Warfare Ctr, Res & Technol Div, Chem & Mat Branch, China Lake, CA 93555 USA. NR 20 TC 170 Z9 172 U1 4 U2 29 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD JAN PY 1998 VL 75 IS 1 BP 119 EP 121 PG 3 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA YM871 UT WOS:000071110000052 ER PT J AU Coyle, WJ Ryan, MT Nowicki, MJ AF Coyle, WJ Ryan, MT Nowicki, MJ TI Adenomatous changes in the hamartomatous polyps of Ruvalcaba-Myhre-Smith syndrome SO JOURNAL OF CLINICAL GASTROENTEROLOGY LA English DT Article ID FAMILIAL JUVENILE POLYPOSIS; INTESTINAL POLYPOSIS; COLI C1 USN, Med Ctr, Div Adult Gastroenterol, Portsmouth, VA 23708 USA. USN, Med Ctr, Div Pediat Gastroenterol, Portsmouth, VA 23708 USA. USN, Med Ctr, Dept Pathol, Portsmouth, VA 23708 USA. RP Coyle, WJ (reprint author), USN, Med Ctr, Div Adult Gastroenterol, Portsmouth, VA 23708 USA. NR 15 TC 3 Z9 3 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0192-0790 J9 J CLIN GASTROENTEROL JI J. Clin. Gastroenterol. PD JAN PY 1998 VL 26 IS 1 BP 85 EP 87 DI 10.1097/00004836-199801000-00024 PG 3 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA YU351 UT WOS:000071708400024 PM 9492874 ER PT J AU Kwon, YW Wojcik, GW AF Kwon, YW Wojcik, GW TI Impact study of sandwich composite structures with delamination SO JOURNAL OF COMPOSITE MATERIALS LA English DT Article ID LOW-VELOCITY IMPACT AB Finite element analyses were conducted to analyze the dynamic response of an unbalanced sandwich beam, a balanced sandwich beam, and a balanced sandwich plate subject to a low energy impact. In particular, strain versus time history, failure location and mode, and the influence of an existing delamination crack on the failure were investigated. It was found that, in the presence of a small delamination crack, the failure load of a sandwich composite structure increased compared to that of the non-delaminated structure. For a small crack, failure under impact loading was core shearing, that occurred away from the crack tip. However, as the delamination crack length increased, the core shearing failure occurred at the crack tip under a reduced impact load. Thus, the failure location shifted moving away from the crack tip to the crack tip as the delamination crack size increased from a small size to a large size. The failure load for a large crack structure was significantly smaller than that of the non-delaminated structure. Core shearing failure was followed by delmaination at the core/faceplate interfaces. When the initial delamination crack size became longer than half of the beam length, the crack further propagated through the interface. Furthermore, a delamination crack did not result in a substantial increase in the maximum deflection compared to that of the non-delaminated specimen. Thus, detection of delamination cracks was difficult from the deflection measurement under a low energy impact. Finally, the effect of crack surface friction on the dynamic behaviour and failure of the sandwich structures was small. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. RP Kwon, YW (reprint author), USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. NR 11 TC 13 Z9 14 U1 0 U2 3 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0021-9983 J9 J COMPOS MATER JI J. Compos Mater. PY 1998 VL 32 IS 5 BP 406 EP 430 PG 25 WC Materials Science, Composites SC Materials Science GA ZD347 UT WOS:000072676100001 ER PT J AU Puh, JS Wagner, PA Little, BJ Bradley, WL AF Puh, JS Wagner, PA Little, BJ Bradley, WL TI The effect of biofouling on graphite/epoxy composites SO JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH LA English DT Article; Proceedings Paper CT 1st Symposium on Non-Aerospace Applications for Composite Materials CY NOV, 1996 CL NEW ORLEANS, LOUISIANA SP Amer Soc Testing & Mat, Comm D 30 Composite Mat DE polymeric composites; microbiologically influenced corrosion; biodeterioration; mechanical testing; acoustic emission; microbial; carbon fiber; seawater ID DEGRADATION AB This research program seeks to determine if the presence of marine microorganisms and the biofouling they produce will accelerate the degradation of graphite/epoxy composite materials. Graphite/epoxy samples were conditioned for 4 months in sterilized seawater(no microorganisms), natural seawater (with microorganisms), and air. In addition, half of the tested samples were also subjected to three-point bending while conditioning. Moisture absorption data was gathered before and after immersion and correlated with tensile and acoustic emission data. Results of tensile tests showed seawater in general had a larger effect on ultimate tensile strength than microorganism effects. However, sample stress state while conditioning had negligible effect on mechanical properties. These results were most likely due to plasticization of the matrix and relief of fabrication residual stresses through moisture absorption and fiber dominated behavior of the specimens. Acoustic emission results showed that the trend for high amplitude hits for each exposure condition was consistent with the tensile test results. However, due to the effects of moisture on three different relaxation mechanisms, the low amplitude hits were not as consistent. C1 Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. USN, Res Lab, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. RP Puh, JS (reprint author), Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. NR 16 TC 1 Z9 1 U1 1 U2 7 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0884-6804 J9 J COMPOS TECH RES JI J. Compos. Technol. Res. PD JAN PY 1998 VL 20 IS 1 BP 59 EP 67 PG 9 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA ZP544 UT WOS:000073764100008 ER PT J AU Liu, C Zheng, X Sung, CH AF Liu, C Zheng, X Sung, CH TI Preconditioned multigrid methods for unsteady incompressible flows SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE time-dependent flow; incompressible; preconditioning ID OMEGA TURBULENCE MODEL; NAVIER-STOKES; EQUATIONS; SCHEME AB A highly efficient numerical approach based on multigrid and preconditioning methods is developed for modeling 3D steady and time-dependent incompressible flows. The k-omega turbulence model is used to estimate the effects of turbulence. The model equations are solved together with the N-S equations in a strongly coupled way, and acceleration techniques like the multigrid method are also used for the turbulence model equations. For unsteady problems, a dual-time stepping procedure is adopted to satisfy the divergence-free constraint and to obtain a time-accurate solution. To improve the performance of this approach for small physical time steps, a modification to residual smoothing parameters is proposed. The numerical algorithm and the turbulence model are validated first by calculating unsteady inviscid flow around an oscillating cylinder, unsteady laminar flow past a circular cylinder, and steady high-Reynolds number turbulent how over a 6 : 1, prolate spheroid. Then the three-dimensional time-dependent turbulent how over a spheroid when it is undergoing a pitch-up maneuver is calculated and compared with experimental data. (C) 1998 Academic Press. C1 Louisiana Tech Univ, Dept Math & Stat, Ruston, LA 71272 USA. Front Range Sci Computat Inc, Boulder, CO 80304 USA. USN, Ctr Surface Warfare, Carderock Div, David Taylor Model Basin, Bethesda, MD 20084 USA. RP Zheng, X (reprint author), ADINA R&D Inc, 71 Elton Ave, Watertown, MA 02172 USA. NR 28 TC 169 Z9 178 U1 0 U2 15 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JAN 1 PY 1998 VL 139 IS 1 BP 35 EP 57 DI 10.1006/jcph.1997.5859 PG 23 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA YZ719 UT WOS:000072284000003 ER PT J AU Qi, LX Cao, YQ Stantley, NG Zhang, G AF Qi, LX Cao, YQ Stantley, NG Zhang, G TI Image-based analysis and fabrication of ceramic-made restorations. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Univ Maryland, USN, Air Warfare Ctr, Div Aircraft, College Pk, MD 20742 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 524 BP 171 EP 171 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800526 ER PT J AU Nicoll, BK Peters, RJ AF Nicoll, BK Peters, RJ TI Heat generation during ultrasonic instrumentation of dentin as affected by different irrigation methods. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Sch Dent, Bethesda, MD 20814 USA. USN, Detachment, Inst Dent Res, Bethesda, MD 20084 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 610 BP 182 EP 182 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800612 ER PT J AU Byers, P Batchu, H Chiego, D Dennison, J Fan, PL Yaman, P AF Byers, P Batchu, H Chiego, D Dennison, J Fan, PL Yaman, P TI The effects of bur and alloy type on particle-size generation. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Ann Arbor, MI USA. Univ Michigan, Ann Arbor, MI 48109 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 683 BP 191 EP 191 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800681 ER PT J AU Pederson, ED Stone, ME AF Pederson, ED Stone, ME TI Mercury management of dental-wastewater streams using secondary treatments SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Inst Dent Res, NTC, Great Lakes, IL 60088 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 687 BP 191 EP 191 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800683 ER PT J AU O'Loughlin, P Miller, GA Wang, YF D'Alesandro, M Ferry, L Diehl, SR AF O'Loughlin, P Miller, GA Wang, YF D'Alesandro, M Ferry, L Diehl, SR TI Effect of smoking cessation on total serum IgG2. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Sch Dent, Bethesda, MD 20814 USA. Geocenters Inc, Bethesda, MD USA. NIDR, NIH, Bethesda, MD 20892 USA. Loma Linda VA Med Ctr, Loma Linda, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 693 BP 192 EP 192 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800690 ER PT J AU Schultz, ST Pederson, ED AF Schultz, ST Pederson, ED TI Technique for removing polymer-bound mercury from dental-waste water. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Dent Res Inst, Great Lakes, IL 60088 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1103 BP 243 EP 243 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801096 ER PT J AU Jensen, SA Walker, TL Hutter, JW Nicoll, BK AF Jensen, SA Walker, TL Hutter, JW Nicoll, BK TI A comparison of the cleaning efficacy of passive sonic activation versus passive ultrasonic activation after hand instrumentation in molar root canals. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Sch Dent, Bethesda, MD 20814 USA. USN, Dent Res Inst, Bethesda, MD 20814 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1323 BP 271 EP 271 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801317 ER PT J AU Hoag, J Towle, H Nicoll, B AF Hoag, J Towle, H Nicoll, B TI Comparison of a particulate and block preparation of decalcified freeze-dried bone allografts in human periodontal bone defects. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Sch Dent, Bethesda, MD 20814 USA. USN, Dent Res Inst, Bethesda, MD 20084 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1574 BP 302 EP 302 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801570 ER PT J AU Scherrer, SS Kelly, JR Quinn, GD Xu, K AF Scherrer, SS Kelly, JR Quinn, GD Xu, K TI Fracture toughness (K-Ic) of a dental porcelain determined by fractographic analysis. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Univ Geneva, CH-1211 Geneva 4, Switzerland. NIST, Gaithersburg, MD 20899 USA. USN, Sch Dent, Bethesda, MD 20814 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI B MA 193 BP 656 EP 656 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZK546 UT WOS:000073335400191 ER PT J AU Kelly, JR Hunter, BV Brenyo, MR Peterson, IM AF Kelly, JR Hunter, BV Brenyo, MR Peterson, IM TI Simulating clinical failure during in vitro testing of all-ceramic crowns. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Sch Dent, Bethesda, MD 20814 USA. NIST, Gaithersburg, MD 20899 USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI B MA 1175 BP 778 EP 778 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZK546 UT WOS:000073335401166 ER PT J AU Pei, S Geivelis, M Maddalozzo, D Robinson, P Simonson, L AF Pei, S Geivelis, M Maddalozzo, D Robinson, P Simonson, L TI Effect of subgingival povidone-iodine irrigation on periodontal pockets. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Northwestern Univ, Chicago, IL 60611 USA. USN, Inst Dent Res, Great Lakes, IL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI B MA 1317 BP 796 EP 796 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZK546 UT WOS:000073335401308 ER PT J AU Mundorff-Shrestha, SA Proskin, HM Billings, RJ Cornell, G Simonson, L AF Mundorff-Shrestha, SA Proskin, HM Billings, RJ Cornell, G Simonson, L TI Conventional versus immunoassay enumeration of mutans streptococci and lactobacilli SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Univ Rochester, Eastman Dent Ctr, Rochester, NY USA. USN, Dent Res Inst, Great Lakes, IL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI B MA 1782 BP 854 EP 854 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZK546 UT WOS:000073335401776 ER PT J AU Pederson, ED Simonson, LG Turner, DW AF Pederson, ED Simonson, LG Turner, DW TI Relationships between host response factors and periodontal clinical/bacterial parameters. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Inst Dent Res, Great Lakes, IL 60088 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI B MA 1822 BP 859 EP 859 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZK546 UT WOS:000073335401816 ER PT J AU Morgan, MA Schwering, FK AF Morgan, MA Schwering, FK TI Mode expansion solution for scattering by a material filled rectangular groove SO JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS LA English DT Meeting Abstract C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU VSP BV PI ZEIST PA PO BOX 346, 3700 AH ZEIST, NETHERLANDS SN 0920-5071 J9 J ELECTROMAGNET WAVE JI J. Electromagn. Waves Appl. PY 1998 VL 12 IS 4 BP 467 EP 468 DI 10.1163/156939398X00890 PG 2 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA ZW461 UT WOS:000074413300004 ER PT J AU Burlaga, L Fitzenreiter, R Lepping, R Ogilvie, K Szabo, A Lazarus, A Steinberg, J Gloeckler, G Howard, R Michels, D Farrugia, C Lin, RP Larson, DE AF Burlaga, L Fitzenreiter, R Lepping, R Ogilvie, K Szabo, A Lazarus, A Steinberg, J Gloeckler, G Howard, R Michels, D Farrugia, C Lin, RP Larson, DE TI A magnetic cloud containing prominence material: January 1997 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CORONAL MASS EJECTIONS; DISAPPEARING SOLAR FILAMENTS; HELIOSPHERIC CURRENT SHEET; FLUX-ROPES; 1 AU; IONOSPHERIC CONVECTION; GEOMAGNETIC-ACTIVITY; NONLINEAR EVOLUTION; COMPOUND STREAMS; CURRENT LOOPS AB This work discusses the relations among (1) an interplanetary force-free magnetic cloud containing a plug of cold high-density material with unusual composition, (2) a coronal mass ejection (CME), (3) an eruptive prominence, and (4) a model of prominence material supported by a force-free magnetic flux rope in a coronal streamer. The magnetic cloud moved past the Wind spacecraft located in the solar wind upstream of Earth on January 10 and 11, 1997, The magnetic field configuration in the magnetic cloud was approximately a constant-cu, force-free flux rope, The (4)He(++)/H(+) abundance in the most of the magnetic cloud was similar to that of the streamer belt material, suggesting an association between the magnetic cloud and a helmet streamer. A very cold region of exceptionally high density was detected at the rear of the magnetic cloud. This dense region had an unusual composition, including (1) a relatively high (10%) (4)He(++)/He(+) abundance (indicating a source near the photosphere), and (2) (4)He(+), with an abundance relative to (4)He(++) of similar to 1%, and the unusual charge states of O(5+) and Fe(5+) (indicating a freezing-in temperature of (1.6-4.0) x 10(5) degrees K, which is unusually low, but consistent with that expected for prominence material). Thus we suggest that the high-density region might be prominence material. The CME was seen in the solar corona on January 6, 1997, by the large angle and spectrometric coronagraph (LASCO) instrument on SOHO shortly after an eruptive prominence. A helmet streamer was observed near the latitude of the eruptive prominence a quarter of a solar rotation before and after the eruptive prominence. These observations are consistent with recent models, including the conceptual model of Low and Hundhausen [1995] for a quasi-static helmet streamer containing a force-free flux rope which supports prominence material and the dynamical model of Wu et al. [1997] for CMEs produced by the disruption of such a configuration. C1 NASA, Extraterr Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94708 USA. RP Burlaga, L (reprint author), NASA, Extraterr Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 82 TC 194 Z9 195 U1 0 U2 4 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 JAN 1 PY 1998 VL 103 IS A1 BP 277 EP 285 DI 10.1029/97JA02768 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA YQ714 UT WOS:000071415900024 ER PT J AU Kaminer, I Pascoal, A Hallberg, E Silvestre, C AF Kaminer, I Pascoal, A Hallberg, E Silvestre, C TI Trajectory tracking for autonomous vehicles: An integrated approach to guidance and control SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article AB A new methodology is introduced for integrated design of guidance and control systems for autonomous vehicles (AVs). The methodology proposed borrows from the theory of gain-scheduled control and leads to an efficient procedure for the design of controllers for AVs to accurately track reference trajectories defined in an inertial reference frame. The paper illustrates the application of this procedure to the design of a tracking controller for the unmanned air vehicle Bluebird. The design phase is summarized, and the performance of the resulting controller is assessed in simulation using dynamic models of the vehicle and its sensor suite. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut Engn, Monterey, CA 93943 USA. Univ Tecn Lisboa, Dept Elect Engn, Inst Super Tecn, P-1096 Lisbon, Portugal. Univ Tecn Lisboa, Inst Syst & Robot, Inst Super Tecn, P-1096 Lisbon, Portugal. RP Kaminer, I (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut Engn, Monterey, CA 93943 USA. RI Silvestre, Carlos/F-9189-2010; OI Silvestre, Carlos/0000-0002-5096-5527; PASCOAL, ANTONIO /0000-0002-0657-6671 NR 21 TC 123 Z9 126 U1 5 U2 20 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD JAN-FEB PY 1998 VL 21 IS 1 BP 29 EP 38 DI 10.2514/2.4229 PG 10 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA YR201 UT WOS:000071470900005 ER PT J AU Li, FY Bainum, PM Creamer, NG Fisher, S AF Li, FY Bainum, PM Creamer, NG Fisher, S TI Rapid reorientation maneuvers of experimental spacecraft with a pendulum appendage SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA/AAS Astrodynamics Specialist Conference CY JUL 29-31, 1996 CL SAN DIEGO, CALIFORNIA SP Amer Inst Aeronaut & Astronaut, AAS ID MINIMUM-TIME MANEUVERS; FLEXIBLE SPACECRAFT AB Recent numerical and experimental results are reported for the near-minimum-time maneuvers of the U.S. Naval Research Laboratory's Reconfigurable Spacecraft Host for attitude and Pointing Experiments (RESHAPE) facility with a pendulum appendage, which is a three-dimensional, freely rotating platform supported by a spherical air bearing system and equipped with a certain payload, reaction wheels, rate gyros, and an onboard computer. The pendulum appendage is attached vertically by a string to the Edge of the RESHAPE's circular platform. The maneuver control uses the summation of an open-loop feedforward command and a feedback command. The feedforward part is obtained from the solution of the time-optimal control of a simplified system. The feedback central, used to damp out small disturbances during the maneuver and postmaneuver errors, is a proportional control formed by feeding back the error between the feedforward command and the measurements. Maneuver simulations and tests show the advantage of using the flexible modeling in the control design. Some interesting phenomena, such as the change of the number of inner switching points and the trajectory feedforward effect, are also presented and discussed. Numerical and experimental results are presented to illustrate the success of the three-dimensional RESHAPE maneuvers and the excellent correlation between the simulations and tests. C1 Howard Univ, Dept Mech Engn, Washington, DC 20059 USA. USN, Res Lab, Control Syst Branch, Washington, DC 20375 USA. USN, Res Lab, Syst Anal Branch, Washington, DC 20375 USA. RP Li, FY (reprint author), Howard Univ, Dept Mech Engn, Washington, DC 20059 USA. NR 9 TC 8 Z9 9 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD JAN-FEB PY 1998 VL 21 IS 1 BP 164 EP 171 DI 10.2514/2.4213 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA YR201 UT WOS:000071470900024 ER PT J AU Zelenin, AK Trudell, ML Gilardi, RD AF Zelenin, AK Trudell, ML Gilardi, RD TI Synthesis and structure of dinitroazofurazan SO JOURNAL OF HETEROCYCLIC CHEMISTRY LA English DT Article AB The synthesis of dinitroazofurazan (3) was achieved from readily available diaminofurazan (6) in two steps and 20% overall yield. The structure of the energetic material 3 was unequivocally confirmed by X-ray crystallography and found to have a crystal density of 1.742 g/cm(3). C1 Univ New Orleans, Dept Chem, New Orleans, LA 70148 USA. USN, Res Lab, Washington, DC 20375 USA. RP Zelenin, AK (reprint author), Univ New Orleans, Dept Chem, New Orleans, LA 70148 USA. NR 17 TC 37 Z9 46 U1 0 U2 4 PU HETERO CORPORATION PI ODESSA PA PO BOX 993, ODESSA, FL 33556-0993 USA SN 0022-152X J9 J HETEROCYCLIC CHEM JI J. Heterocycl. Chem. PD JAN-FEB PY 1998 VL 35 IS 1 BP 151 EP 155 PG 5 WC Chemistry, Organic SC Chemistry GA ZC750 UT WOS:000072613600028 ER PT J AU Blair, PJ Riley, JL Levine, BL Lee, KP Craighead, N Francomano, T Perfetto, SJ Gray, GS Carreno, BM June, CH AF Blair, PJ Riley, JL Levine, BL Lee, KP Craighead, N Francomano, T Perfetto, SJ Gray, GS Carreno, BM June, CH TI Cutting edge: CTLA-4 ligation delivers a unique signal to resting human CD4 T cells that inhibits interleukin-2 secretion but allows Bcl-X-L induction SO JOURNAL OF IMMUNOLOGY LA English DT Article ID CD28 COSTIMULATION; ACTIVATION; PROLIFERATION; EXPRESSION; LYMPHOCYTES; APOPTOSIS; SURVIVAL; ANTIGEN AB We have assessed the functional effects of a panel of CTLA-4 mAbs on resting human CD4(+) T cells, Our results demonstrate that some CTLA-4 mAbs can inhibit proliferative responses of resting CD4(+) cells and cell cycle transition from G(1) to G(1). The inhibitory effects of CTLA-4 were evident within 4 h, at a time when cell surface CTLA-4 expression remained undetectable, Other CTLA-4 mAbs had no detectable inhibitory effects, indicating that binding of Ab to CTLA-4 alone is not sufficient to mediate down-regulation of T cell responses, Interestingly, while IL-2 production was shut off, inhibitory anti-CTLA-4 mAbs permitted induction and expression of the cell survival gene bcl-X-L. Consistent with this observation, cells remained viable and apoptosis was not detected after CTLA-4 ligation. C1 USN, Med Res Inst, Immune Cell Biol Program 061, Bethesda, MD 20889 USA. Walter Reed Army Inst Res, Rockville, MD 20850 USA. Henry M Jackson Fdn Advancement Mil Med, US Mil HIV Res Program, Bethesda, MD 20889 USA. Genet Inst, Cambridge, MA 02140 USA. RP June, CH (reprint author), USN, Med Res Inst, Immune Cell Biol Program 061, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. EM juneC@nmripo.nmri.nnmc.navy.mil RI Levine, Bruce/D-1688-2009; OI Riley, James/0000-0002-1057-576X NR 27 TC 109 Z9 112 U1 0 U2 1 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD JAN 1 PY 1998 VL 160 IS 1 BP 12 EP 15 PG 4 WC Immunology SC Immunology GA YW266 UT WOS:000071915100003 PM 9551948 ER PT J AU Tsai, TF Yu, YX Li, JL Putvatana, R Zhang, R Wang, SQ Halstead, SB AF Tsai, TF Yu, YX Li, JL Putvatana, R Zhang, R Wang, SQ Halstead, SB TI Immunogenicity of live attenuated SA14-14-2 Japanese encephalitis vaccine - A comparison of 1- and 3-month immunization schedules SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article AB Live attenuated SA14-14-2 Japanese encephalitis (JE) vaccine has been safe and effective in > 100 million immunized children, but its current administration schedule of two doses given a year apart does not lend itself to inclusion in established Expanded Program of Immunization (EPI) schedules of childhood immunization. Immune responses to immunization at shorter intervals were compared in middle-school-aged children immunized with two doses separated by 1 month (n = 116) or 2.5 months (n = 115), Two vaccine lots were compared, Seroconversion to the vaccine was observed in 100% of vaccinees immunized in the 1-month schedule and in 94% (lot 2) and 100% (lot 1) of vaccinees immunized in the 2.5-month schedule, Geometric mean titers were almost 2-fold higher with the longer schedule, The routine administration of JE SA14-14-2 vaccine to infants in an EPI schedule should be possible using either interval. C1 Ctr Dis Control & Prevent, Div Vector Borne Infect Dis, Natl Ctr Infect Dis, Ft Collins, CO USA. Inst Control Pharmaceut & Biol Prod, Temple Heaven, Beijing, Peoples R China. Chengdu Inst Biol Prod, Chengdu, Peoples R China. USN, Med Res & Dev Command, Bethesda, MD USA. RP Tsai, TF (reprint author), Ctr Dis Control & Prevent, Div Vector Borne Infect Dis, Natl Ctr Infect Dis, Foothills Campus,POB 2087, Ft Collins, CO USA. NR 14 TC 28 Z9 30 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD JAN PY 1998 VL 177 IS 1 BP 221 EP 223 DI 10.1086/517358 PG 3 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA YM597 UT WOS:000071080700033 PM 9419193 ER PT J AU Chen, Y McCarron, RM Spatz, M AF Chen, Y McCarron, RM Spatz, M TI Nitric oxide modulation of ET-1-induced Ca2+ mobilization in human cerebromicrovascular endothelial cell SO JOURNAL OF NEUROCHEMISTRY LA English DT Meeting Abstract C1 USN, Med Res Inst, RMP, Bethesda, MD 20892 USA. NINDS, Stroke Branch, NIH, Bethesda, MD 20892 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0022-3042 J9 J NEUROCHEM JI J. Neurochem. PY 1998 VL 70 SU 1 BP S71 EP S71 PG 1 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA YY627 UT WOS:000072167200284 ER PT J AU Hart, AKE Greinwald, JH Shaffrey, CI Postma, GN AF Hart, AKE Greinwald, JH Shaffrey, CI Postma, GN TI Thoracic duct injury during anterior cervical discectomy: a rare complication - Case report SO JOURNAL OF NEUROSURGERY LA English DT Article; Proceedings Paper CT Annual Meeting of the Virginia-Society-of-Otolaryngology-Head-and-Neck-Surgery CY APR, 1996 CL HOT SPRINGS, VIRGINIA SP Virginia Soc Otolaryngol Head & Neck Surg DE thoracic duct; cervical spine; operative complication; discectomy ID RADICAL NECK DISSECTION; CHYLOUS FISTULA; BILATERAL CHYLOTHORAX; MANAGEMENT; SURGERY; NUTRITION AB Chylous fistula resulting from intraoperative injury to the cervical thoracic duct is well described as a complication of neck dissection. However, injury to the thoracic duct during spinal surgery is rarely reported. The authors present the first case of thoracic duct injury occurring during cervical discectomy and fusion via an anterior approach. The anomalous location of the terminal arch of the thoracic duct in this patient contributed to the complication The morbidity of chyle leakage is minimized by its early recognition, a thorough understanding of lymphatic system anatomy, and aggressive management of the thoracic duct injury. C1 USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, Portsmouth, VA 23708 USA. Univ Iowa, Dept Otolaryngol Head & Neck Surg, Ctr Hlth, Iowa City, IA 52242 USA. Henry Ford Hosp, Dept Neurol Surg, Detroit, MI 48202 USA. Henry Ford Hosp, Dept Orthopaed Surg, Detroit, MI 48202 USA. Wake Forest Univ, Bowman Gray Sch Med, Dept Otolaryngol, Ctr Voice Disorders, Winston Salem, NC 27103 USA. RP Hart, AKE (reprint author), USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 28 TC 20 Z9 20 U1 0 U2 0 PU AMER ASSOC NEUROLOGICAL SURGEONS PI CHARLOTTESVILLE PA UNIV VIRGINIA, 1224 WEST MAIN ST, STE 450, CHARLOTTESVILLE, VA 22903 USA SN 0022-3085 J9 J NEUROSURG JI J. Neurosurg. PD JAN PY 1998 VL 88 IS 1 BP 151 EP 154 DI 10.3171/jns.1998.88.1.0151 PG 4 WC Clinical Neurology; Surgery SC Neurosciences & Neurology; Surgery GA YN287 UT WOS:000071151800026 PM 9420091 ER PT J AU Mansour, AN Melendres, CA AF Mansour, AN Melendres, CA TI Analysis of X-ray absorption spectra of some nickel oxycompounds using theoretical standards SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID FINE-STRUCTURE SPECTRA; ELECTRONIC-STRUCTURE; EDGE STRUCTURE; K-EDGE; SPECTROSCOPY; EXAFS; OXIDES; ELECTROCHEMISTRY; HYDROXIDES; LIXNI2-XO2 AB X-ray absorption spectra have been measured for NiO, beta-Ni(OH)(2), alpha-Ni(OH)(2), LiNiO2, and KNiIO6 samples, which contain nickel with valency in the range 2-4. Information on the local structure and nature of bonding of nickel compounds has been derived using theoretical standards generated with the FEFF code. The Ni K-edge energy was found to shift to higher values by about 1.5 eV per unit change in valency of nickel. The energy of the preedge peak (generally attributed to the transition from the Is core states to the 3d unoccupied states) shifts to higher values by about 0.6 eV per unit change in valency of nickel. A many body amplitude reduction factor (S-0(2)) of 0.77 +/- 0.03 for Ni K-edge absorption can be used to scale theoretical spectra to fit the experimental ones in order to accurately determine the coordination numbers for compounds with complex structures. Our results show that chemical effects are very small and can be ignored for reliable structural analysis. Results of local structure for the first, second, and third coordination spheres for NiO are consistent with those derived from X-ray diffraction data. The results for beta-Ni(OH)(2) are much-closer in agreement with those derived from the neutron diffraction data rather than the X-ray diffraction data. The results for alpha-Ni(OH)(2) differ significantly from those based on the idealized structure model proposed by Bode et al. In fact, the structure within the hexagonal planes for alpha-Ni(OH)(2) is similar to that for beta-Ni(OH)(2). The apparent contraction in the Ni-Ni distance of the third coordination sphere for alpha-Ni(OH)(2) relative to that for beta-Ni(OH)(2), which was previously reported by others, is not real and can be attributed to structural disorder. The Ni-O bond length for divalent nickel with an octahedral coordination is in the range 2.06-2.08 Angstrom. The first coordination sphere for LiNiO2 consists of four and two oxygens at 1.91 and 2.06 Angstrom, respectively, rather than six oxygens at 2.04 Angstrom, as predicted by the X-ray diffraction data. The short distance is characteristic of Ni3+-O2- bonds and Ni2+-O- bonds, while the long distance is characteristic of Ni2+-O2- bonds. The local structure for LiNiO2 is consistent with the fact that the charge-compensating mechanism is largely due to oxygen 2p holes. The Ni-Ni second-shell distance for LiNiO2 is consistent with that based on the X-ray and neutron diffraction data. The Ni-O bond length for quadrivalent Ni in KNiIO6 is 1.88 Angstrom. The Ni-O bond length varies with nickel valency in a nonlinear manner. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Mansour, AN (reprint author), USN, Ctr Surface Warfare, Carderock Div, Code 684,Bldg 19-A250,9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 61 TC 70 Z9 70 U1 6 U2 31 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 1 PY 1998 VL 102 IS 1 BP 65 EP 81 DI 10.1021/jp9619853 PG 17 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA YP850 UT WOS:000071322100009 ER PT J AU Bouamrane, F Tadjeddine, A Tenne, R Butler, JE Kalish, R Levy-Clement, C AF Bouamrane, F Tadjeddine, A Tenne, R Butler, JE Kalish, R Levy-Clement, C TI Underpotential deposition of Cu on boron-doped diamond thin films SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID CARBON-FILMS; ELECTRODES; NITRATE; CVD; ADSORPTION; IMPEDANCE; REDUCTION AB The deposition of copper on boron-doped diamond thin-film electrodes was investigated, Three kinds of boron-doped diamond films were studied: a film deposited on a silicon wafer, a second grown on a tungsten substrate. and a third, similar to the first, but surface-amorphized (bombarded) by ion beam irradiation. The films were investigated by a number of techniques. Linear potential sweep experiments in 0.1 M H2SO4 + 0.001 M CuSO4 solution showed that, besides the peak due to bulk copper deposition, a "prewave" peak is present in the voltammogram of the first two electrodes and not in the third one. An electrochemical activation at negative potential was imperative for the appearance of the "prewave" peak. The amount of copper involved was less than 2% of a monolayer. The comparison between spectroscopic and electrochemical investigations leads to the interpretation that the "prewave" peak corresponds to an underpotential deposition of Cu on graphitic inclusions in the diamond electrode, or along the grain boundaries, probably by intercalation. C1 CNRS, LPSB, UPR 1332, F-92195 Meudon, France. Univ Paris 11, LURE, F-91405 Orsay, France. Weizmann Inst Sci, Dept Mat & Interfaces, IL-76100 Rehovot, Israel. USN, Res Labs, Washington, DC 20375 USA. Technion Israel Inst Technol, Inst Solid State, IL-32000 Haifa, Israel. RP Levy-Clement, C (reprint author), CNRS, LPSB, UPR 1332, 1 Pl Aristide Briand, F-92195 Meudon, France. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 33 TC 44 Z9 45 U1 3 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 1 PY 1998 VL 102 IS 1 BP 134 EP 140 DI 10.1021/jp971516g PG 7 WC Chemistry, Physical SC Chemistry GA YP851 UT WOS:000071322200020 ER PT J AU George, RD Snow, AW Shirk, JS Barger, WR AF George, RD Snow, AW Shirk, JS Barger, WR TI The alpha substitution effect on phthalocyanine aggregation SO JOURNAL OF PORPHYRINS AND PHTHALOCYANINES LA English DT Article DE dimerization; aggregation; phthalocyanine isomers; cumylphenoxy ID AQUEOUS COBALT(II)-4,4',4'',4'''-TETRASULFOPHTHALOCYANINE; TETRASODIUM SALT; DIMERIZATION; ION; DYE AB The dimerization and tendency to form higher aggregates of two isomeric metal-free phthalocyanine compounds with tetracumylphenoxy peripheral substitution at the alpha (1 or 4, 5 or 8, 9 or 12, 13 or 16) and beta (2 or 3, 6 or 7, 10 or 11, 14 or 15) positions has been analysed by spectroscopic measurements. The dimerization constants in chloroform solution are 1.3 x 10(1) M-1 and 7.0 x 10(3) M-1 respectively. At concentrations greater than 10(-3) M, the beta phthalocyanine isomer forms a spectroscopically resolvable higher aggregate. Q-band spectra of the dimer of each isomer and of the aggregate of the beta isomer in chloroform solution were generated. Comparison of these spectra with the corresponding thin film spectra of each isomer indicates that the stronger tendency toward aggregation of the beta isomer extends into the solid state. The difference in aggregating tendency of the two isomers was attributed to a steric constraint of the alpha isomer that restricts conformational freedom and, consequently, hinders formation of dimer and higher order complexes. (C) 1998 John Wiley & Sons, Ltd. C1 USN, Res Lab, Washington, DC 20375 USA. RP George, RD (reprint author), Space & Naval Warfare Syst Ctr, Code D361, San Diego, CA 92152 USA. NR 29 TC 118 Z9 119 U1 4 U2 17 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1088-4246 J9 J PORPHYR PHTHALOCYA JI J. Porphyr. Phthalocyanines PD JAN-FEB PY 1998 VL 2 IS 1 BP 1 EP 7 DI 10.1002/(SICI)1099-1409(199801/02)2:1<1::AID-JPP43>3.0.CO;2-L PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 208JM UT WOS:000080987300001 ER PT J AU Ellis, RL Lalande, F Jia, HY Rogers, CA AF Ellis, RL Lalande, F Jia, HY Rogers, CA TI Ballistic impact resistance of SMA and spectra hybrid graphite composites SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article DE ballistic impact; hybrid composites; SMA; Spectra (TM) ID LOW-VELOCITY IMPACT; RESIDUAL STRENGTH; CFRP; DAMAGE AB The effect of adding small amounts of high strain hybrid components on the impact resistance of graphite epoxy composites subjected to projectiles traveling at ballistic velocities (greater than 900 ft/sec) has been studied. The hybrid components tested include superelastic shape memory alloy (SMA) and a high performance extended chain polyethylene (ECPE) known as Spectra(TM). In all cases, the embedded SMA fibers were pulled through the graphite without straining to their full potential. It is believed that this is due to high strain rate effects coupled with a strain mismatch between the tough SMA and the brittle epoxy resin. However, a significant increase in energy absorption was found by adding ECPE and ECPE/SMA layers to the backface of the composite. C1 Boeing Co, Long Beach, CA 90846 USA. USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. Virginia Polytech Inst & State Univ, Ctr Intelligent Mat Syst & Struct, Blacksburg, VA 24061 USA. Univ S Carolina, Columbia, SC 29208 USA. RP Lalande, F (reprint author), Boeing Co, Long Beach, CA 90846 USA. NR 20 TC 15 Z9 16 U1 0 U2 3 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1998 VL 17 IS 2 BP 147 EP 164 PG 18 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA YY399 UT WOS:000072143200005 ER PT J AU Kwon, YW Baron, DT AF Kwon, YW Baron, DT TI Numerical predictions of progressive damage evolution in particulate composites SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article ID FIBROUS COMPOSITES; BEHAVIOR; MODULI; MODEL AB A method is presented for calculating stresses and strains in a loaded particulate composite structure (specimen) as damage initiates and grows. Load is incrementally applied to a numerically simulated specimen. For every load increment, a finite element method model is used to calculate the composite stresses and strains at each point. A micromechanical model uses the composite strains to calculate the stresses and strains in the composite's component materials, the particles and matrix. A damage model uses the matrix strains to determine values for local matrix damage, and to set reductions in the stiffnesses of damaged matrix material regions, each of which is proportional to the associated damage value. At damaged locations, the micromechanical model uses the reduced matrix stiffnesses to calculate reduced composite stiffnesses. All reduced matrix and composite stiffnesses calculated during a load increment are used in the next load increment. Matrix strain values are set which determine damage initiation, growth, and saturation. Damage saturation indicates matrix material failure, and for saturation the composite stiffness approaches zero. At a specimen point a matrix crack will form or extend when the point becomes saturated with damage. Numerical simulation predictions are presented, and compared to experimental data. Plots are included showing stress and strain variation, and crack growth. C1 USAF, Res Lab, Raytheon STX Corp, Edwards AFB, CA 93524 USA. USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. RP Baron, DT (reprint author), USAF, Res Lab, Raytheon STX Corp, Edwards AFB, CA 93524 USA. NR 16 TC 3 Z9 3 U1 0 U2 0 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1998 VL 17 IS 8 BP 691 EP 711 PG 21 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA ZP710 UT WOS:000073780700002 ER PT J AU Kram, M AF Kram, M TI Use of SCARS petroleum hydrocarbon sensor technology for real-time indirect DNAPL detection SO JOURNAL OF SOIL CONTAMINATION LA English DT Article DE real-time petroleum; hydrocarbon detection capabilities; petroleum hydrocarbons; chlorinated solvents; vinyl chloride AB The Site Characterization and Analysis Cone Penetrometer System (SCAPS), equipped with real-time petroleum, oils and lubricants (POL) hydrocarbon detection capabilities was used to delineate subsurface contaminant releases at a former fire fighter training facility. Records indicated that both petroleum hydrocarbons and chlorinated solvents were released at the site. The investigators advanced the SCAPS petroleum hydrocarbon sensor to depths beneath the water table of the principal water bearing zone. The water table was located 8 to 10 ft (2.44 to 3.05 m) below ground surface (bgs) across the site. Fuel compounds were detected at depths ranging from 7.5 to 13.3 ft (4.05 m) bgs and from 37.5 to 51.0 ft (11.48 to 15.54 m) bgs. Petroleum compounds present in the deeper soils suggest that chlorinated solvents (which are more dense than water) transported them to these unexpected depths as they migrated via gravity and advection. Analyses of soil samples taken from the subaqueous depths in question confirmed that vinyl chloride was cc-mingled with petroleum hydrocarbons. This discovery suggests that the SCAPS fuel hydrocarbon detection system may be capable of indirectly delineating vadose zone and subaqueous chlorinated solvents and other dense non-aqueous phase liquid (DNAPL) plumes at contaminant release sites. C1 USN, Facil Engn Serv Ctr, Port Hueneme, CA USA. RP Kram, M (reprint author), USN, Facil Engn Serv Ctr, Port Hueneme, CA USA. NR 10 TC 13 Z9 13 U1 0 U2 0 PU CRC PRESS INC PI BOCA RATON PA 2000 CORPORATE BLVD NW, JOURNALS CUSTOMER SERVICE, BOCA RATON, FL 33431 USA SN 1058-8337 J9 J SOIL CONTAM JI J. Soil Contam. PY 1998 VL 7 IS 1 BP 73 EP 86 PG 14 WC Environmental Sciences SC Environmental Sciences & Ecology GA YW511 UT WOS:000071943100004 ER PT J AU Cauraugh, JH Kellogg, RM AF Cauraugh, JH Kellogg, RM TI Individuals who have had polio present a clean test of sensorimotor integration theory SO JOURNAL OF SPORT & EXERCISE PSYCHOLOGY LA English DT Meeting Abstract C1 Univ Florida, Gainesville, FL 32611 USA. USN, Bethesda Natl Hosp, Bethesda, MD 20084 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMAN KINETICS PUBL INC PI CHAMPAIGN PA 1607 N MARKET ST, CHAMPAIGN, IL 61820-2200 USA SN 0895-2779 J9 J SPORT EXERCISE PSY JI J. Sport Exerc. Psychol. PY 1998 VL 20 SU S BP S54 EP S54 PG 1 WC Hospitality, Leisure, Sport & Tourism; Psychology, Applied; Psychology; Sport Sciences SC Social Sciences - Other Topics; Psychology; Sport Sciences GA 130WT UT WOS:000076543900108 ER PT J AU Poston, WL Wegman, EJ Solka, JL AF Poston, WL Wegman, EJ Solka, JL TI A parallel algorithm for subset selection SO JOURNAL OF STATISTICAL COMPUTATION AND SIMULATION LA English DT Article DE parallel subset selection; information matrix; effective independence distribution; hat matrix AB Prior to performing an analysis of a large data set, it is often desirable to process a subset of the data only. Current methods of subset selection choose points in a random manner, which can lead to poor solutions. The method for selection described in this paper employs the Effective Independence Distribution (EID) method that chooses observations that optimize the determinant of the information matrix. Since the method requires repeated calculations of three matrix multiplications and a matrix inverse, it is computationally intensive for extremely large data sets. A recursive form of the EID is developed here which is suitable for parallelization. The parallel method is described in detail, and load balancing and communication issues are addressed. Implementation results on the Intel Paragon show that this is an effective parallel algorithm. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. George Mason Univ, Ctr Computat Stat, Fairfax, VA 22030 USA. RP Poston, WL (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, G33, Dahlgren, VA 22448 USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0094-9655 J9 J STAT COMPUT SIM JI J. Stat. Comput. Simul. PY 1998 VL 60 IS 1 BP 1 EP 17 DI 10.1080/00949659808811869 PG 17 WC Computer Science, Interdisciplinary Applications; Statistics & Probability SC Computer Science; Mathematics GA YZ729 UT WOS:000072285500001 ER PT J AU Gingras, DF AF Gingras, DF TI Single mode excitation, attenuation, and backscatter in shallow water SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID REVERBERATION; PROPAGATION; EQUATION AB In Shallow water, bottom interaction may have a negative effect on the performance of active sonars. In this paper it is shown that a vertical array of weighted sources driven in an appropriate frequency band dan be used to minimize the deleterious effects of bottom interaction, i.e., attenuation and backscatter. Simulation results (based on two-dimensional cw field calculations) are presented for three canonical geoacoustic models using both a winter and summer sound speed profile. It is shown through selective excitation of only mode one there exists a favorable frequency band providing both minimum attenuation and bottom generated backscatter. C1 USN, Control & Ocean Surveillance Ctr San Diego, San Diego, CA 92152 USA. RP Gingras, DF (reprint author), USN, Control & Ocean Surveillance Ctr San Diego, San Diego, CA 92152 USA. NR 28 TC 5 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JAN PY 1998 VL 103 IS 1 BP 195 EP 204 DI 10.1121/1.421087 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA YR454 UT WOS:000071496900018 ER PT J AU Hansford, RE Vorwald, J AF Hansford, RE Vorwald, J TI Dynamics workshop on rotor vibratory loads prediction SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY LA English DT Article; Proceedings Paper CT 52nd Annual Forum of the American-Helicopter-Society CY JUN 04-06, 1996 CL WASHINGTON, D.C. SP Amer Helicopter Soc AB This paper reviews the results of a Dynamics Workshop focusing on the correlation of vibratory hub load predictions, from eight advanced aeroelastic codes, with Lynx flight test measurements. Simple "Baseline Models" are first established with near uniform characteristics for all codes, to enable vibration prediction improvements to be quantified as the codes are upgraded to "Current Technology" standard. The effects on vibration correlation are illustrated for various changes in analytical models including; free wakes, fuselage upwash, unsteady aerodynamics and Finite Element versus Modal methods, Some of these analytical modelling improvements are incorporated to become "Improved Technology Models" which are subsequently reevaluated with night test loads to identify rotor modelling deficiencies. On average, codes are not able to predict vibratory loads to an accuracy any greater than 50% of the Lynx measured loads. C1 GKN Westland Helicopters Ltd, Yeovil, Somerset, England. USN, NSWC, CD, Bethesda, MD USA. RP Hansford, RE (reprint author), GKN Westland Helicopters Ltd, Yeovil, Somerset, England. NR 18 TC 20 Z9 22 U1 1 U2 2 PU AMER HELICOPTER SOC INC PI ALEXANDRIA PA 217 N WASHINGTON ST, ALEXANDRIA, VA 22314 USA SN 0002-8711 J9 J AM HELICOPTER SOC JI J. Am. Helicopter Soc. PD JAN PY 1998 VL 43 IS 1 BP 76 EP 87 PG 12 WC Engineering, Aerospace SC Engineering GA YV227 UT WOS:000071802100008 ER PT J AU Healy, LM Travisano, JJ AF Healy, LM Travisano, JJ TI Automatic rendering of astrodynamics expressions for efficient evaluation SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article AB In this paper, we describe the automatic rendering of expressions computed using symbolic manipulation. Computations from astrodynamics frequently can be put in a fixed hierarchy of polynomials and Fourier series. Once in this form, FORTRAN subprograms can be generated automatically in a form that lends itself to numerical evaluation. The goal of the current work is to present an approach for using symbolic manipulation techniques to produce a Fortran representation of the normalized Hamiltonian and other supporting equations representing as many of the actual physical effects on satellites as possible. C1 USN, Res Lab, Washington, DC 20375 USA. Boeing Co, Hanover, MD 21076 USA. RP Healy, LM (reprint author), USN, Res Lab, Code 8233, Washington, DC 20375 USA. NR 19 TC 5 Z9 5 U1 0 U2 0 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 EI 2195-0571 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD JAN-MAR PY 1998 VL 46 IS 1 BP 65 EP 81 PG 17 WC Engineering, Aerospace SC Engineering GA 152BH UT WOS:000077755200004 ER PT J AU Neta, B Vallado, D AF Neta, B Vallado, D TI On satellite umbra/penumbra entry and exit positions SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article AB The problem of computing Earth satellite entry and exit positions through the Earth's umbra and penumbra, for satellites in elliptical orbits, is solved without the use of a quartic equation. A condition for existence of a solution in the case of a cylindrical shadow is given. This problem is of interest in case one would like to include perturbation force resulting from solar radiation pressure. Most satellites (including geosynchronous) experience periodic eclipses behind the Earth. Of course when the satellite is eclipsed, it's not exposed to solar radiation pressure. When we need extreme accuracy, we must develop models that turn the solar radiation calculations "on" and "off," as appropriate, to account for these periods of inactivity. C1 USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RP Neta, B (reprint author), USN, Postgrad Sch, Dept Math, Code MA ND, Monterey, CA 93943 USA. RI Neta, Beny/B-1737-2009 NR 9 TC 11 Z9 12 U1 0 U2 0 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD JAN-MAR PY 1998 VL 46 IS 1 BP 91 EP 103 PG 13 WC Engineering, Aerospace SC Engineering GA 152BH UT WOS:000077755200006 ER PT J AU Fuller, J Carlin, RT Osteryoung, RA Koranaios, P Mantz, R AF Fuller, J Carlin, RT Osteryoung, RA Koranaios, P Mantz, R TI Anodization and speciation of magnesium in chloride-rich room temperature ionic liquids SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID INCREASED ELECTROCHEMICAL WINDOW; CHLOROALUMINATE MOLTEN-SALTS; SODIUM; SOLVENTS; LITHIUM; SYSTEMS AB Magnesium anodization was examined in room temperature AlCl3:EMIC and AlCl3:DMPIC ionic liquids, where EMIC = 1-ethyl-3-methylimidazolium chloride and DMPIC = 1, 2-dimethyl-3-propylimidazolium chloride. For all melts, the AlCl3:organic chloride mole ratio was <1, yielding chloride-rich (i.e., basic) compositions. The rate of magnesium anodization was limited by diffusion of chloride ions to the electrode surface. From the Cottrell slopes for magnesium anodization at a Mg disk electrode and for chloride oxidation at a Pt disk electrode, the chloride stoichiometry of the anodization process in AlCl3:EMIC was determined to be 4.1 (+/- 0.5), corresponding to the formation of soluble MgCl42-. Similar chloride stoichiometry was found in AlCl3:DMPIC. MgCl2 buffers the melt to approximate neutrality from the basic side, dissolving as MgCl42-. Magnesium metal was chemically stable in basic AlCl3:DMPIC, but it reacted completely and irreversibly with basic AlCl3:EMIC to produce colored organic byproducts. Some comments are made on the acidity of NiCl2 and CdCl2 in the basic melts. C1 Covalent Associates Inc, Woburn, MA 01801 USA. N Carolina State Univ, Dept Chem, Raleigh, NC 27695 USA. RP Fuller, J (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. NR 22 TC 16 Z9 17 U1 1 U2 15 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 1998 VL 145 IS 1 BP 24 EP 28 DI 10.1149/1.1838204 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA YQ399 UT WOS:000071382900009 ER PT J AU Nguyen, PP Pearson, DH Tonucci, RJ Babcock, K AF Nguyen, PP Pearson, DH Tonucci, RJ Babcock, K TI Fabrication and characterization of uniform metallic nonostructures using nanochannel glass SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID DEFINED MAGNETIC-STRUCTURES; FORCE MICROSCOPY; CARBON NANOTUBES; NANOWIRES; ARRAYS; LITHOGRAPHY; CYLINDERS; WIRES; DISK AB We demonstrate the ability to fabricate large-scale patterned two-dimensional arrays of identical nanometer size metallic wires with high aspect ratios and packing densities of greater than 3 x 10(9) elements/cm(2). The arrays are made by electrodeposition into nanochannel glass templates. Scanning electron microscopy and tunneling electron microscopy have been used to characterize the nanostructures. Magnetic characterizations of the ferromagnetic wire arrays using a superconducting quantum interference device magnetometer and a magnetic force microscope reveal one-dimensional characteristics with preferred magnetization direction perpendicular to the array film plane and enhanced coercivities compared to the bulk values. Preliminary results on fabrication of nanometer size metallic tubes are also presented. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Digital Instruments Inc, Santa Barbara, CA 93103 USA. RP Nguyen, PP (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 25 TC 48 Z9 49 U1 1 U2 10 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 1998 VL 145 IS 1 BP 247 EP 251 DI 10.1149/1.1838242 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA YQ399 UT WOS:000071382900047 ER PT J AU Chen, TJ Tao, R Rife, JC Hunter, WR AF Chen, TJ Tao, R Rife, JC Hunter, WR TI Optical constants and related electronic energy bands of lithium triborate crystal in the 6-12-eV region SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID LIB3O5 CRYSTAL; GENERATION; RADIATION AB Reflectance of lithium triborate crystal in the 6-12-eV region is measured with synchrotron radiation, and the principal values of optical constants are derived. Six absorption peaks are found in both X-and Y-polarized spectra. Among them the five transitions of the Y-polarized peaks and three of the X-polarized peaks are identified. The measurement suggests that the energy of the lowest conducting band 4A(2) is 7.3 eV rather than 7.57 eV, as previously reported. (C) 1998 Optical Society of America. C1 So Illinois Univ, Dept Phys, Carbondale, IL 62901 USA. USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. RP Chen, TJ (reprint author), So Illinois Univ, Dept Phys, Carbondale, IL 62901 USA. OI Tao, Rongjia/0000-0001-5058-4401 NR 23 TC 8 Z9 8 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD JAN PY 1998 VL 15 IS 1 BP 47 EP 52 DI 10.1364/JOSAB.15.000047 PG 6 WC Optics SC Optics GA YT825 UT WOS:000071648800007 ER PT J AU Herman, WN Cline, JA AF Herman, WN Cline, JA TI Chielectric relaxation: chromophore dynamics in an azo-dye-doped polymer SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID 2ND HARMONIC-GENERATION; 2ND-HARMONIC GENERATION; DIELECTRIC-RELAXATION; NONLINEAR OPTICS; AMORPHOUS POLYMERS; POLED POLYMER; FILMS; BIREFRINGENT; MECHANISMS; SYSTEMS AB A new experimental method for observing chromophore relaxation dynamics in nonlinear optical polymer systems is described. The method is similar to dielectric relaxation measurements, which probe the linear susceptibility chi((1)), but this new method is chromophore selective and probes the nonlinear susceptibility chi((2)) in the frequency domain, monitoring second-harmonic generation during the application of a strong ac electric field. The out-of-phase component of chi((2)) exhibits behavior similar to that of the loss component in dielectric relaxation and is shown to be unaffected by electric-field-induced third-order effects. The relation to dielectric relaxation is discussed, and stretched exponential parameters are extracted for a Disperse-Red-1/poly(methylmethacrylate) guest-host system. (C) 1998 Optical Society of America. C1 USN, Air Warfare Ctr, Div Aircraft, Patuxent River, MD 20670 USA. RP Herman, WN (reprint author), USN, Air Warfare Ctr, Div Aircraft, Code 4556, Patuxent River, MD 20670 USA. NR 41 TC 10 Z9 10 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD JAN PY 1998 VL 15 IS 1 BP 351 EP 358 DI 10.1364/JOSAB.15.000351 PG 8 WC Optics SC Optics GA YT825 UT WOS:000071648800042 ER PT J AU Kwon, YW Kim, C AF Kwon, YW Kim, C TI Micromechanical model for thermal analysis of particulate and fibrous composites SO JOURNAL OF THERMAL STRESSES LA English DT Article ID DAMAGE AB Thermal stresses occur at the micromechanical level of a particle-/fiber-reinforced composite caused by the mismatch of coefficients of thermal expansion (CTE) of the constituent materials like the particle/fiber and the matrix binder. The stresses affect the service envelope of a composite structure when it is subject to an external load. Thus this article presented a simplified, analytical, three-dimensional, micromechanical model so as to compute microthermal stresses occurring in the constituent materials as well as the effective CTE of a composite based on their materials properties. The analytical solutions for both particulate and fibrous composites were compared to the results obtained from finite element analyses as well as other results if available. The comparison of the effective CTEs and the microthermal stresses between the present solutions and the finite element results showed an excellent agreement. In addition, a parametric study was conducted in order to determine the effects of each parameter of the constituent materials on the effective CTE, microthermal stresses, and the solution errors. The orthogonal away technique used in the Taguchi method was adopted for the parametric study. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 94943 USA. Kookmin Univ, Sch Mech Engn, Seoul, South Korea. RP Kwon, YW (reprint author), USN, Postgrad Sch, Dept Mech Engn, 700 Dyer Rd, Monterey, CA 94943 USA. EM ywkwon@me.nps.navy.mil NR 14 TC 18 Z9 18 U1 0 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 0149-5739 EI 1521-074X J9 J THERM STRESSES JI J. Therm. Stresses PD JAN-FEB PY 1998 VL 21 IS 1 BP 21 EP 39 DI 10.1080/01495739808956133 PG 19 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA YR171 UT WOS:000071467500002 ER PT J AU Sanz, W Platzer, MF AF Sanz, W Platzer, MF TI On the Navier-Stokes calculation of separation bubbles with a new transition model SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 41st International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 10-13, 1996 CL BIRMINGHAM, ENGLAND ID DIFFERENCE AB Laminar separation bubbles are commonly observed on turbomachinery blades and therefore require effective methods for their prediction. Therefore, a newly developed transition model by Gostelow et al. (1996) is incorporated into an upwind-biased Navier-Stokes code to simulate laminar-turbulent transition in the boundary layer. A study of the influence of the two adjustable parameters of the model, the transition onset location and the spot generation rate, is conducted and it is found that it can predict laminar separation bubbles, measured on a NACA 0012 airfoil. Additional results are presented for separation bubbles in an annular compressor cascade. C1 Graz Univ Technol, Inst Thermal Turbomachinery & Machine Dynam, A-8010 Graz, Austria. USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Sanz, W (reprint author), Graz Univ Technol, Inst Thermal Turbomachinery & Machine Dynam, A-8010 Graz, Austria. NR 26 TC 6 Z9 6 U1 0 U2 0 PU ASME PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD JAN PY 1998 VL 120 IS 1 BP 36 EP 42 PG 7 WC Engineering, Mechanical SC Engineering GA YV220 UT WOS:000071801400005 ER PT J AU Hobson, GV Williams, AJH Rickel, HJG AF Hobson, GV Williams, AJH Rickel, HJG TI Laser-Doppler-velocimetry measurements in a cascade of compressor blades at stall SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 41st International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 10-13, 1996 CL BIRMINGHAM, ENGLAND ID FLOW AB Compressor stall was simulated in the Low-Speed Cascade Wind Tunnel at the Turbopropulsion Laboratory of the Naval Postgraduate School. The test blades were of controlled-diffusion design with a solidity of 1.67, and stalling occurred at 10 deg of incidence above the design inlet air angle. All measurements were taken at a flow Reynolds number based on chord length, of 700,000. Laser-sheet flow visualization techniques showed that the stalling process was unsteady and occurred over the whole cascade. Detailed laser-Doppler-velocimetry measurements over the suction side of the blades showed regions of continuous and intermittent reverse flow. The measurements of the continuous reverse flow region at the lending edge were the first data of their kind in the lending edge separation bubble. The regions of intermittent reverse flow, measured with laser-Doppler velocimeter, corresponded to the flow visualization studies. Blade surface pressure measurements showed a decrease in normal force on the blade, as would be expected at stall. Data are presented in a form that characterizes the unsteady positive and negative velocities about their mean, for both the continuous reverse flow regions and the intermittent reverse flow regions. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Turbopropuls Lab, Monterey, CA 93943 USA. RP Hobson, GV (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Turbopropuls Lab, Monterey, CA 93943 USA. NR 8 TC 1 Z9 1 U1 1 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD JAN PY 1998 VL 120 IS 1 BP 170 EP 178 PG 9 WC Engineering, Mechanical SC Engineering GA YV220 UT WOS:000071801400022 ER PT J AU Glembocki, OJ Rebbert, ML Prokes, SM Sethian, JD Marrian, CRK Chan, LY AF Glembocki, OJ Rebbert, ML Prokes, SM Sethian, JD Marrian, CRK Chan, LY TI Optical properties of low-density foams considered as targets for inertial confinement fusion SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID ORGANIC AEROGELS AB An optical method for measuring scattered light, namely by analyzing the transmitted light, is used to characterize the optical properties of low-density foams that are candidates as targets for inertial confinement fusion. This method allows us to simultaneously measure both scattering and intrinsic absorption in the foam. Three types of foams have been examined: two have similar chemistries and are based on either ethylene glycol dimetacrylate (EGDM) or trimethylolpropane trimethacrylate (TMPT), The other one is based on resorcinol formaldehyde (RF). We observe that while the RF foams are orange in color and nearly transparent, the EGDM/TMPT based foams are white and opaque. The opacity of these foams is shown to be due to light scattering by particles having dimensions on the order of 200 nm. In contrast, the light scattering from the RF foams indicates that the structures scattering light are on the order of 20 nm. The orange color of the RF foams is shown to be due to intrinsic absorption of light by the polymer comprising the foam. The onset of absorption is seen to shift towards the blue as the foams age, Index matching to the TMPT foam using ethanol is shown to significantly reduce the scattering. (C) 1998 American Vacuum Society. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sci & Applicat Int Corp, Mclean, VA 22102 USA. RP Glembocki, OJ (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. NR 13 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 1998 VL 16 IS 1 BP 50 EP 56 DI 10.1116/1.581010 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA YT383 UT WOS:000071597100008 ER PT J AU Fahroo, F AF Fahroo, F TI Optimal placement of controls for a one-dimensional active noise control problem SO KYBERNETIKA LA English DT Article AB In this paper, we investigate the optimal location of secondary sources (controls) to enhance the reduction of the noise field in a one-dimensional acoustic cavity. We first formulate the active control strategy as a linear quadratic tracking (LQT) problem in a Hilbert space, and then formulate the optimization problem as minimizing an appropriate performance criterion based on the LQT cost function with respect to the location of the controls. A numerical scheme based on the Legendre-tau method is used to approximate the control and the optimization problems. Numerical examples are presented to illustrate the effect of location of controls on the reduction of the noise field. C1 USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. RP Fahroo, F (reprint author), USN, Postgrad Sch, Dept Math, Code Ma-Ff, Monterey, CA 93943 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU KYBERNETIKA PI PRAGUE 8 PA POD VODARENSKOU VEZI 4, PRAGUE 8 182 08, CZECH REPUBLIC SN 0023-5954 J9 KYBERNETIKA JI Kybernetika PY 1998 VL 34 IS 6 BP 655 EP 665 PG 11 WC Computer Science, Cybernetics SC Computer Science GA 177QC UT WOS:000079221100005 ER PT S AU McGill, RA Chrisey, DB Pique, A Mlsna, TE AF McGill, RA Chrisey, DB Pique, A Mlsna, TE BE Dubowski, JJ Dyer, PE TI Matrix assisted pulsed laser evaporation (MAPLE) of functionalized polymers: Applications with chemical sensors SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM III) at LASE 98 at Photonics West CY JAN 26-28, 1998 CL SAN JOSE, CA SP Int Soc Optical Engn DE MAPLE; pulsed laser evaporation; polymer; coatings; chemical sensor; chemoselective; surface acoustic wave; SAW; MALDI; laser; matrix AB A novel polymer processing technique, matrix assisted pulsed laser evaporation (MAPLE), for the deposition of organic and inorganic polymers and other materials, as ultrathin and uniform coatings has been developed. The technique involves directing a pulsed excimer laser beam onto a frozen matrix target composed of the polymeric material in a solvent. The process gently lifts polymeric material into the gas phase with no apparent decomposition. A plume of material is developed normal to the target, and a substrate positioned incident to this plume is coated with the polymer. The MAPLE technique offers a number of features that are difficult to achieve with other polymer coating techniques, including: nano-meter to micron thickness range, sub monolayer thickness precision, high uniformity, applicability to photosensitive materials, and patterning of surfaces. Highly functionalized polysiloxanes have been synthesized and deposited on a range of substrates by the MAPLE technique and characterized by: infrared spectroscopy, and optical microscopy. High quality, uniform and adherent polysiloxane coatings are produced by the optimized MAPLE technique. The physicochemical properties of the coating are unaffected by the process, and precise thickness control of the coating is straightforward. C1 USN, Res Lab, Washington, DC 20375 USA. RP McGill, RA (reprint author), USN, Res Lab, Code 6670, Washington, DC 20375 USA. NR 0 TC 8 Z9 8 U1 1 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2713-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3274 BP 255 EP 266 DI 10.1117/12.309520 PG 4 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL30Y UT WOS:000075053800029 ER PT S AU Horwitz, JS Carter, AC Chang, W Pond, JM Kirchoefer, SW Chrisey, DB AF Horwitz, JS Carter, AC Chang, W Pond, JM Kirchoefer, SW Chrisey, DB BE Dubowski, JJ Dyer, PE TI Structure/property relationships in pulsed laser deposited ferroelectric thin films for frequency agile microwave electronics SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM III) at LASE 98 at Photonics West CY JAN 26-28, 1998 CL SAN JOSE, CA SP Int Soc Optical Engn AB Low loss ferroelectric thin films deposited by pulsed laser deposition (PLD) are currently being used to develop a new class of tunable microwave circuits based on the electric field dependence of the dielectric constant. Single phase, (100) oriented Ba0.5Sr0.5TiO3 (BST) films have been deposited onto (100) LaAlO3, SrTiO3, and MgO substrates. Interdigitated capacitors have been used to measure the dielectric constant and dissipation factor of these films as a function of DC bias and temperature at 1 MHz and as a function of DC bias at 1 to 20 GHz at room temperature. A low phase noise voltage controlled oscillator is currently being developed for use at frequencies from 1 - 20 GHz. To achieve low phase noise in the in the oscillator will require the loss tangent in the ferroelectric to be less than or equal to 5 x 10(-3). Origins of the dielectric loss are being investigated using optical techniques. Optical imaging of the ferroelectric films using confocal scanning optical microscopy (CSOM) shows reproducible polarization fluctuations over sub-micrometer length scales for BST films deposited onto SrTiO3 which are not observed for films deposited onto MgO. Dielectric loss in the ferroelectric film is reduced through a combination of post deposition processing and donor/acceptor doping of the films. The lowest dielectric loss measured at microwave frequencies (tan delta = 0.01 at 1 - 10 GHz) has been in a post-deposition annealed Ba0.5Sr0.5TiO3 film doped with similar to 1-2 atomic % Mn. C1 USN, Res Lab, Washington, DC 20375 USA. RP Horwitz, JS (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2713-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3274 BP 278 EP 284 DI 10.1117/12.309522 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL30Y UT WOS:000075053800031 ER PT S AU Chrisey, DB Kim, J Stroud, RM Koller, D Osofsky, MS Soulen, RJ Byers, JM Eddy, CR Auyeung, RCY Horwitz, JS AF Chrisey, DB Kim, J Stroud, RM Koller, D Osofsky, MS Soulen, RJ Byers, JM Eddy, CR Auyeung, RCY Horwitz, JS BE Dubowski, JJ Dyer, PE TI Pulsed laser deposition of YBa2Cu3O7-La0.67Sr0.33MnO3 thin film multilayers for spin injection devices SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM III) at LASE 98 at Photonics West CY JAN 26-28, 1998 CL SAN JOSE, CA SP Int Soc Optical Engn AB Pulsed laser deposition (PLD) has been used for the growth of high quality YBa2Cu3O7 and La0.67Sr0.33MnO3 thin films and multilayers for electronic device applications. In particular, YBa2Cu3O7 - (SrTiO3, CeO2) La0.67Sr0.33MnO3 trilayer devices were fabricated to study the supercurrent suppression by the injection of a spin-polarized quasiparticle current. Our results show that the critical current for a YBa2Cu3O7 - 50 Angstrom SrTiO3 - La0.67Sr0.33MnO3 device was found to decrease from 120 mA to 15 mA, for an injection current of 60 mA of spin polarized current yielding a negative current gain of similar to 1.8. The effect of film microstructure on the critical current suppression was investigated. Defects in the SrTiO3 and CeO2 layers were found to control the device properties. Once optimized, spin injection represents a new approach to fabricating superconducting transistors which could impact electronic systems for many important next generation. C1 USN, Res Lab, Washington, DC 20375 USA. RP Chrisey, DB (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Stroud, Rhonda/C-5503-2008; Osofsky, Michael/A-1050-2010 OI Stroud, Rhonda/0000-0001-5242-8015; NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2713-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3274 BP 285 EP 292 DI 10.1117/12.309523 PG 4 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL30Y UT WOS:000075053800032 ER PT S AU Schumacher, PW Gilbreath, C Lydick, ED Davis, MA AF Schumacher, PW Gilbreath, C Lydick, ED Davis, MA BE Kamerman, GW TI Error analysis for laser-based metric calibration of the Naval Space Surveillance System SO LASER RADAR TECHNOLOGY AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Laser Radar Technology and Applications III CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE Satellite Laser Ranging; calibration; space surveillance; satellite catalog AB The Naval Space Surveillance System is a network of continuous-wave VHF interferometer stations designed to detect Earth satellites. Angular metric data from the system are used in real time to update the catalog of known space objects maintained by the Air Force and Naval components of United States Space Command. For many years, the system has operated with a near real-time calibration of the detector electronics but without a rigorous tie to an external reference frame. One way to establish such a tie is by comparing system measurements with data derived by Satellite Laser Ranging. In principle, public-domain laser ranging data on geodetic satellites can always be used to generate a few high-precision reference orbits whose ephemerides can be compared with surveillance measurements. In the right circumstances, special laser tracking data on aml suitable satellite can be taken simultaneously with surveillance measurements and compared directly. Both approaches offer benefit to space surveillance operations, and both have been demonstrated in previous work. This analysis initiates the analytical investigation of how precisely we can resolve errors in the surveillance measurements, using laser ranging-derived data. Equations are presented which relate surveillance measurement uncertainties to reference data uncertainties in explicit terms. Simple geometric measurement models are considered, rather than detailed physical measurement models, in order to provide fundamental understanding of how errors transform in the two types of calibration considered. The resulting formulae are suitable for deriving calibration requirements and simplified error budgets, either analytically or by numerical simulation. C1 USN, Space Command, Dahlgren, VA 22448 USA. RP Schumacher, PW (reprint author), USN, Space Command, Code VN63,5280 4th St, Dahlgren, VA 22448 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2829-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3380 BP 202 EP 215 PG 14 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BL68V UT WOS:000076320100022 ER PT S AU Barnds, WJ Coffey, S Davis, M AF Barnds, WJ Coffey, S Davis, M BE Kamerman, GW TI Determination of TiPS libration using laser radar SO LASER RADAR TECHNOLOGY AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Laser Radar Technology and Applications III CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE tethered satellite; tether deployer; libration; TiPS; attitude determination; orbit determination; ephemeris; SLR; retroreflector AB This paper describes the use of satellite laser ranging (SLR) data for determining the orbital and librational motion of the Tether Physics and Survivability (TiPS) experiment. We provide a description of new analytical tools and methodologies developed for determining the dynamics of the system. The results gleaned from a year's worth of laser tracking are presented to provide a history of the librational and rotational motion of the TIPS system. Finally, the case for using SLR for libration determination on future tether experiments is presented. C1 USN, Res Lab, Washington, DC 20375 USA. RP Barnds, WJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2829-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3380 BP 231 EP 242 DI 10.1117/12.327196 PG 12 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BL68V UT WOS:000076320100024 ER PT S AU Feldstein, MJ Scherer, NF AF Feldstein, MJ Scherer, NF BE Dai, HL Freund, HJ TI Femtosecond correlated optical reactivity and scanning tunneling microscopy studies of metal surfaces SO LASER TECHNIQUES FOR SURFACE SCIENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Techniques for Surface Science III CY JAN 29-31, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers AB A new experimental technique, correlated optical reactivity and scanning tunneling microscopy (CORSTM), is shown to be a uniquely powerful tool for the study of spatially localized reactivity of surfaces. In particular, CORSTM measurements directly correlate electromagnetic field enhancements that affect chemical dynamics and reactivity with surface topography on the length scale of a few nanometers. These measurements are based on the detection of surface plasmon polariton mediated multi-photon ionization (SPP-MPI) from metal surfaces using ultrafast optical excitation and scanning probe microscopy photoelectron detection. The CORSTM approach is extended to a pump-probe scheme facilitating spatially localized measurement of hot electron dynamics. The experimental results provide direct confirmation of the optimal structural topographies for surface enhanced spectroscopy predicted by electromagnetic theories. CORSTM will provide a better understanding of phenomena that involve plasmons through the direct measurement of structure-function correlations. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Feldstein, MJ (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. NR 0 TC 5 Z9 5 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2711-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3272 BP 58 EP 65 DI 10.1117/12.307147 PG 8 WC Chemistry, Physical; Optics; Spectroscopy SC Chemistry; Optics; Spectroscopy GA BL12X UT WOS:000074381100008 ER PT J AU Goldman, L AF Goldman, L TI Future of laser dermatology SO LASERS IN SURGERY AND MEDICINE LA English DT Article DE laser diagnostics; microscopies; multiwavelength lasers; melanocyte cells; langerhans cells AB Background and Objective: Laser dermatology, a long-time model for laser tissue interactions, will play an important part in the future of research, diagnostics, and therapeutics. Study Design/Materials and Methods: Laser research continues in photobiology, especially in molecular reactions, and it continues at the cellular level in melanocyte and Langerhans cells. Results: Laser diagnostics in the development of opto-electronics concern new developments in imagery. Some studies include new types of microscopes for living skin and vary from the portable illuminated skin microscopes, the current dermatoscopes, to the coaxial polarizing microscope and the new scanning confocal microscope of Gmitro for living tissues. The regular confocal microscope for fixed tissue slides will revolutionize dermatopathology. The other research microscopes include the ultrasonic biomedical microscope and the IR microscope and the holographic microscope of optical phase conjugation used for living tissues. Conclusion: New lasers for therapy include micromedical lasers, economical junction diode lasers alone and for pumping solid-state lasers, FEL of the future, and multiwavelength laser units. These later units include seven-wavelength units of barium, copper vapor and ruby, and are available for other heavy metal laser heads, ds gold-628 nm and lead-722 nm. Copper vapor can pump also Ti sapphire. The MOPO series (200 nm in the UV to >4,500 in the IR) is the most extensive modern multiwavelength laser box type. (C) 1998 Wiley-Liss, Inc.(dagger) C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Dermatol, San Diego, CA 92134 USA. RP Goldman, L (reprint author), USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. NR 19 TC 5 Z9 5 U1 1 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0196-8092 J9 LASER SURG MED JI Lasers Surg. Med. PY 1998 VL 22 IS 1 BP 3 EP 8 DI 10.1002/(SICI)1096-9101(1998)22:1<3::AID-LSM3>3.0.CO;2-T PG 6 WC Dermatology; Surgery SC Dermatology; Surgery GA YP485 UT WOS:000071281500003 PM 9443142 ER PT S AU Ratna, BR Nelson, KS Li, H Wilson, C Naciri, J AF Ratna, BR Nelson, KS Li, H Wilson, C Naciri, J BE Shashidhar, R TI Electroclinic liquid crystals for analog gray scale displays and devices SO LIQUID CRYSTAL MATERIALS, DEVICES, AND APPLICATIONS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Liquid Crystal Materials, Devices, and Applications VI CY JAN 26-27, 1998 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, Soc Photo Opt Instrumentat Engineers DE electroclinic effect; chiral smectic A; electrooptic effects; gray scale applications; high resolution displays AB Chiral smectic A liquid crystals with large electroclinic coefficients and fast response times have been developed. The capability of achieving the optimum tilt angle of 22.5 degrees for applied fields less than 3V/mu m, opens up the possibility developing silicon based high-resolution reflective displays without compromising on resolution and speed. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ratna, BR (reprint author), USN, Res Lab, Code 6900, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2737-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3297 BP 2 EP 7 DI 10.1117/12.304534 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BK88V UT WOS:000073807800001 ER PT S AU Hermanns, A Wilson, C Patel, J Gruneberg, K Nelson, K Townsend-Booth, A Ratna, B AF Hermanns, A Wilson, C Patel, J Gruneberg, K Nelson, K Townsend-Booth, A Ratna, B BE Shashidhar, R TI Effect of cell thickness on electroclinic liquid crystal response time SO LIQUID CRYSTAL MATERIALS, DEVICES, AND APPLICATIONS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Liquid Crystal Materials, Devices, and Applications VI CY JAN 26-27, 1998 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, Soc Photo Opt Instrumentat Engineers DE electroclinic liquid crystals; alignment; photoalignment; monolayer; polybutylene terephthalate; response speed; temperature dependence; cell gap AB Electroclinic liquid crystals (ELCs) with their high speed, large contrast, gray scale response and large tilt angles at low operating voltages are highly attractive for use in AMLCDs featuring high frame rate, high resolution, and time sequential color. However, ELC response time usually rises significantly as the applied field is reduced, and has been found to increase as the cell gap is reduced for low operating voltage, high viewing angle devices. We investigate these effects using three alignment layers (polyimide, polybutylene terephthalate (PBT) and a photo-dimerized monolayer (PDML)) at several cell gaps and temperatures with a specific ELC. In the case of PET we find that switching is faster than in the standard polyimide case. Furthermore, thin PET cells switch faster than thick PET cells. We also explore a novel single-sided PET alignment layer scheme, made possible by the in-plane alignment and switching of ELCs. In such a cell, the response time levels off to a constant value at low applied fields, while alignment quality remains high. We conclude that the slowing of the ELC response with decreasing cell gap and decreasing applied field can be reduced substantially by the choice and number of alignment layers. C1 USN, Res Lab, Geocenters Inc, Washington, DC 20375 USA. RP Hermanns, A (reprint author), USN, Res Lab, Geocenters Inc, Code 6900, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2737-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3297 BP 73 EP 80 DI 10.1117/12.304535 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BK88V UT WOS:000073807800010 ER PT S AU Gruneberg, KA Shenoy, DK Naciri, J Chen, MS Davis, A Shashidhar, R AF Gruneberg, KA Shenoy, DK Naciri, J Chen, MS Davis, A Shashidhar, R BE Khoo, IC TI Photo-dimerized monolayers for liquid crystal alignment SO LIQUID CRYSTALS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Liquid Crystals II CY JUL 20-21, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE non-rubbing alignment; monolayer; nematics; active matrix displays; voltage holding ratio ID DISPLAYS AB A non-rubbing process suitable for active matrix LCDs based on a photo-dimerized monolayer (PDML) has been developed. The PDML yields defect free alignment of nematic liquid crystal molecules. The electro-optic characteristics of LCDs fabricated using the photo-dimerized layer are shown to be comparable to those of a rubbed polyimide alignment layer. C1 USN, Res Lab, Geoctr Inc, Washington, DC 20375 USA. RP Gruneberg, KA (reprint author), USN, Res Lab, Geoctr Inc, Code 6950, Washington, DC 20375 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2930-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3475 BP 35 EP 39 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BM33A UT WOS:000078396900004 ER PT J AU Purdy, AP Callahan, JH AF Purdy, Andrew P. Callahan, John H. TI Syntheses of Sublimable Carbon Nitride Materials SO MAIN GROUP CHEMISTRY LA English DT Article ID THIN-FILMS; DEPOSITION; NITROGEN; DICYANAMIDE; ROUTES AB Several potential synthesis routes to C3N4 were reinvestigated. These include thermal decomposition of Hg(SCN)(2), thermal decomposition of CuSCN, and thermal deammonation of melamine. The C3N4 material (1) obtained from Hg(SCN)(2) contained Hg, S, and H as impurities, and the material (2) obtained from decomposition of CuSCN is contaminated with S and H. Both C3N4 products were sublimed under dynamic vacuum at 700 degrees C with a yield of about 40 %, affording 1a and 2a respectively. The sublimates were purer than the starting materials, and a mass spectrum of the vapor showed the presence of molecular C3N4. Melamine could not be fully deammonated to C3N4 by thermolysis. Product 2a had a hardness of 6.2 GPa and a Youngs modulus of 29.8 GPa, and showed a rather high elastic recovery of 81 % during microindentation. C1 [Purdy, Andrew P.; Callahan, John H.] USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Purdy, AP (reprint author), USN, Res Lab, Div Chem, Codes 6120 & 6110, Washington, DC 20375 USA. FU ONR FX We thank the ONR for financial support. Helpful discussions with NRL employee Larry Seitzman are also appreciated. NR 30 TC 8 Z9 8 U1 0 U2 11 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1024-1221 J9 MAIN GROUP CHEM JI Main Group Chem. PY 1998 VL 2 IS 3 BP 207 EP 213 DI 10.1080/10241229812331341379 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA V19PV UT WOS:000208085200006 ER PT B AU Ammeen, ES Gibson, JD Beale, GO AF Ammeen, ES Gibson, JD Beale, GO BE Vukic, Z Roberts, GN TI Robust depth-keeping by means of simultaneous stabilization SO MANOEUVRING AND CONTROL OF MARINE CRAFT LA English DT Proceedings Paper CT 4th IFAC Conference on Manoeuvring and Control of Marine Craft (MCMC 97) CY SEP 10-12, 1997 CL BRIJUNI, CROATIA SP Int Federat Automat Control, IFAC Tech Comm Marine Syst, Croatian Soc Commun, Comp, Electr, Measurement & Control DE ship control; control applications; robust control; simultaneous stabilization ID FEEDBACK-SYSTEM DESIGN; FRACTIONAL REPRESENTATION; PLANTS AB A submarine operating under seaway is affected by hydrodynamic forces from the waves that produce a very large instantaneous downward force on the ship and a very low frequency upward suction force. These forces can adversely affect the submarine's depth-homing capabilities by driving the ship downward out of the critical depth bands or by drawing the ship upward until it broaches. Simultaneous stabilization methods can be used to design control algorithms which stabilize the ship in the presence of these hydrodynamic forces and provide greater stability robustness under these types of perturbations than approaches based on linear quadratic regulator methodologies. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. RP Ammeen, ES (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd, Bethesda, MD 20817 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND BN 0-08-042934-3 PY 1998 BP 71 EP 76 PG 4 WC Automation & Control Systems; Engineering, Marine SC Automation & Control Systems; Engineering GA BM87H UT WOS:000079976000010 ER PT B AU Gibson, JD Beale, GO AF Gibson, JD Beale, GO BE Vukic, Z Roberts, GN TI Stabilizing a nonlinear system over a range of operating points SO MANOEUVRING AND CONTROL OF MARINE CRAFT LA English DT Proceedings Paper CT 4th IFAC Conference on Manoeuvring and Control of Marine Craft (MCMC 97) CY SEP 10-12, 1997 CL BRIJUNI, CROATIA SP Int Federat Automat Control, IFAC Tech Comm Marine Syst, Croatian Soc Commun, Comp, Electr, Measurement & Control DE control application; nonlinear control; simultaneous stabilization AB This paper shows that if the linearization of a nonlinear system can be simultaneously stabilized about two operating points by a single compensator and the closed-loop characteristic polynomials of the two linearized systems satisfy certain conditions, then the nonlinear system linearization is stabilized by the same compensator over a range of operating points. The set of operating points over which the linearization is stabilized corresponds to the set of transfer functions generated by a parametrization of the transfer functions of the linearization about the two original operating points. This result is applied to an example of underwater vehicle control. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. RP Gibson, JD (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd, Bethesda, MD 20817 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND BN 0-08-042934-3 PY 1998 BP 95 EP 98 PG 4 WC Automation & Control Systems; Engineering, Marine SC Automation & Control Systems; Engineering GA BM87H UT WOS:000079976000014 ER PT S AU Wu, CCM Yosenick, T Kim, C Kahn, M Chase, M AF Wu, CCM Yosenick, T Kim, C Kahn, M Chase, M BE Ghosh, A Hiremath, B Sumita, S TI Continuous poling of PZT bars SO MANUFACTURING OF ELECTRONIC MATERIALS AND COMPONENTS SE CERAMIC TRANSACTIONS LA English DT Proceedings Paper CT 99th Annual Meeting of the American-Ceramic-Society CY APR 24-MAY 07, 1997 CL CINCINNATI, OH SP Amer Ceram Soc AB Poling is necessary for the application of piezoelectric material as devices. For thin and small sections of these materials, poling can be readily accomplished with a small electric power supply. For long sections to be poled lengthwise, poling become a major task which would require a rather high voltage power supply. We have developed a continuous poling device using flexible conductive rubber as electrodes. The device is capable of poling long bulk sections without needing a large power supply. Specimens more than 3 inches long have been poled to full d(33) with less than 15 kV. Evaluations of poled PZT 5A ceramic using this device will be presented in terms of piezoelectric parameters such as d(33), dielectric constants and of the uniformity of these properties. C1 USN, Res Lab, Washington, DC 20375 USA. RP Wu, CCM (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 4 Z9 4 U1 0 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-044-0 J9 CERAM TRANS PY 1998 VL 90 BP 21 EP 31 PG 11 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BL75M UT WOS:000076608000003 ER PT J AU Joyner, D Martin, R AF Joyner, D Martin, R TI A constructive algorithm for determining branching rules of Lie group representations SO MAPLETECH LA English DT Article AB We introduce a constructive algorithm for determining the branching rule for a representation of a simple Lie group. This algorithm is based upon the theory of crystal graphs and has been fully implemented in the Maple software package crystal. As an application, we use this algorithm to study a broken symmetry example arising from an approximate model in elementary particle physics. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. RP Joyner, D (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU BIRKHAUSER BOSTON INC PI CAMBRIDGE PA 675 MASSACHUSETTS AVE, CAMBRIDGE, MA 02139 USA SN 1061-5733 J9 MAPLETECH JI Mapletech PY 1998 VL 5 IS 1 BP 23 EP 27 PG 5 WC Computer Science, Software Engineering SC Computer Science GA 115TJ UT WOS:000075681200005 ER PT J AU Wood, AM Phinney, DA Yentsch, CS AF Wood, AM Phinney, DA Yentsch, CS TI Water column transparency and the distribution of spectrally distinct forms of phycoerythrin-containing organisms SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE phycoerythrin; Synechococcus; ocean color; optics ID MARINE SYNECHOCOCCUS; FLOW-CYTOMETRY; CYANOBACTERIA; PHYTOPLANKTON; SPECTROSCOPY; EXCITATION; PIGMENTS; SEA AB Predominance of Type I (phycourobilin-containing) and Type II (phycourobilin-lacking) phycoerythrins (PE) was examined using scanning fluorescence spectroscopy at 176 stations in the northwestern Atlantic off the northeast coast of the United States. Simultaneous optical measurements were made at 75 stations, permitting an analysis of the distribution of spectral types of PE-containing organisms based on geographic position of the stations and on the relative penetration of blue and green wavelengths of light. Stations dominated by Type I PE occurred almost exclusively in very transparent water with high transmissivity for blue light [domnwelling attenuation coefficient; K-d(440) < 0.12] and relatively low attenuation of blue light relative to green light. This pattern was reversed for Type II PE, which dominated in less transparent waters with relatively high attenuation of blue light relative to green light. Type II PE tended to dominate on the continental shelf and slope, and Type I PE tended to dominate in the Sargasso Sea. Regardless of geographic location, there was a transition from dominance by Type I PE to Type II PE as the ratio K-d(440)/K-d(550) exceeded 1.25. Our data suggest that optical parameters are important niche dimensions for marine Synechococcus and that nearshore waters may be classified optically by phycoerythrin characterization. C1 Univ Oregon, Dept Biol, Eugene, OR 97403 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Bigelow Lab Ocean Sci, W Boothbay Harbor, ME 04575 USA. RP Wood, AM (reprint author), Univ Oregon, Dept Biol, Eugene, OR 97403 USA. EM miche@darkwing.uoregon.edu NR 23 TC 55 Z9 55 U1 1 U2 11 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. PY 1998 VL 162 BP 25 EP 31 DI 10.3354/meps162025 PG 7 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA ZC157 UT WOS:000072545600003 ER PT J AU Gardner, JM Shor, AN Jung, WY AF Gardner, JM Shor, AN Jung, WY TI Acoustic imagery evidence for methane hydrates in the Ulleung Basin SO MARINE GEOPHYSICAL RESEARCHES LA English DT Article DE gas hydrates; methane hydrates; Ulleung Basin; acoustic imagery; sidescan; slumping ID EAST SEA SEA; JAPAN SEA; SLOPE-STABILITY; MARGIN; SUBDUCTION; SEDIMENTS; KOREA AB Approximately 12,000 km(2) of acoustic backscatter imagery (sidescan) data and swath bathymetry data were collected jointly by Republic of Korea (ROK) Navy, the Naval Oceanographic Office (NAVOCEANO), Hawaii Mapping Research Group (HMRG) and the Naval Research Laboratory (NRL) in the East Sea (Sea of Japan) in 1995. Preliminary analysis of these data have revealed a large network of canyons with well-developed fan deposits and slumps which were not previously mapped. Also identified is a 1400 km(2) area occupied by more than 300 circular, low-backscatter features ca. 50-1000 m in diameter which are interpreted to be pockmarks or mounds created by escaping methane gas, methane-rich porewater and mud. Indirect evidence for the probable existence of methane gas hydrate include the five following observations: (1) Core samples in the region contain high levels of organic carbon (> 7%), degassing cracks caused by gas expansion, and emit a strong H2S odor. (2) Extensive canyon formation and slumping may have occurred as the result of the destabilization of sediments due to gas accumulation. (3) Several of the high backscatter objects occur at the crest of a bathymetric high under which gas could be accumulating and periodically releasing in a manner similar to that documented on the Vestnesa Ridge in the Norwegian-Greenland Sea. (4) Pockmark-like features have been identified in 3.5 kHz records on the northern edge of the Ulleung Basin. (5) Drill core samples from the morphologically similar Yamato Basin, which is adjacent to the Ulleung Basin, have positively identified methane and numerous gas voids in unconsolidated sediments. No bottom simulating reflector (BSR) has been identified in seismic reflection profiles collected across the slope in Ulleung Basin. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Hawaii Manoa, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. RP Gardner, JM (reprint author), USN, Res Lab, Code 7420, Washington, DC 20375 USA. NR 30 TC 16 Z9 16 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0025-3235 J9 MAR GEOPHYS RES JI Mar. Geophys. Res. PY 1998 VL 20 IS 6 BP 495 EP 503 DI 10.1023/A:1004716700055 PG 9 WC Geochemistry & Geophysics; Oceanography SC Geochemistry & Geophysics; Oceanography GA 306ZM UT WOS:000086628600002 ER PT S AU Jensen, KL AF Jensen, KL BE Zhu, W Pan, LS Felter, TE Holland, C TI Theoretical analysis of Fowler Nordheim parameterization and RLC characteristics for ring cathode field emitter arrays for next generation RF amplifiers SO MATERIALS ISSUES IN VACUUM MICROELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Materials-Research-Society Symposium on Materials Issues in Vacuum Microelectronics CY APR 13-16, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc, Lucent Technol, Bell Lab, Candescent Technol Corp, Motorola AB Of all applications for which field emitter arrays (FEAs) are being designed, RF vacuum microelectronics is the most technically challenging application. The current density is typically three orders of magnitude larger than that required for displays (which require < 0.1 A/cm(2)). Due to their high current density capabilities and instant turn-on, FEAs may be a promising alternative to thermionic emitters for use in Inductive Output Amplifiers (IOAs). An analytical model of a field emitter is used to estimate Fowler Nordheim A and B parameters, effective resistance and capacitance of the array under several GHz modulation, signal propogation lengths, total current and current density, and effects of emitter non-uniformity on the basis of army geometry and materials. Estimates of inductance, resistance, and capacitance are made to estimate the drive power required to produce a bunched electron beam for Inductive Output Amplifier applications. An electronic efficiency of 32% with 15 dB gain may be possible from an army producing 260 mA peak, 71 mA average, current at IO GHz using a TWT helix 1.51 cm long. C1 USN, Res Lab, ESTD, Washington, DC 20375 USA. RP Jensen, KL (reprint author), USN, Res Lab, ESTD, Code 6840, Washington, DC 20375 USA. RI Jensen, Kevin/I-1269-2015 OI Jensen, Kevin/0000-0001-8644-1680 NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-415-7 J9 MATER RES SOC SYMP P PY 1998 VL 509 BP 3 EP 8 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BL60C UT WOS:000075974000001 ER PT S AU Yater, JE Shih, A AF Yater, JE Shih, A BE Zhu, W Pan, LS Felter, TE Holland, C TI Characterization of secondary electron emission from materials with low or negative electron affinity SO MATERIALS ISSUES IN VACUUM MICROELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Materials-Research-Society Symposium on Materials Issues in Vacuum Microelectronics CY APR 13-16, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc, Lucent Technol, Bell Lab, Candescent Technol Corp, Motorola AB Secondary electron emission spectroscopy is used to examine the emission characteristics of diamond films as a function of the bulk and surface properties. We find significant variation in the secondary electron yields measured from diamond surfaces even when energy distribution measurements indicate that a low or negative electron affinity is present. In particular, we observe that the material properties, such as bulk and surface uniformity, surface composition, and impurity and defect concentrations, have a strong affect on the secondary electron yield measurements. Furthermore, the energy distribution of the emitted electrons is found to vary with adsorbate species. In certain cases, the energy distribution changes with adsorbate coverage even though the measured electron intensity remains unchanged. From an analysis of the data, we identify bulk and surface properties needed to optimize the emission characteristics. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yater, JE (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 3 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-415-7 J9 MATER RES SOC SYMP P PY 1998 VL 509 BP 125 EP 130 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BL60C UT WOS:000075974000019 ER PT S AU Hubler, GK Carosella, CA Schiestel, S Cotell, CM Stroud, RM Stoiber, M Grabowski, KS AF Hubler, GK Carosella, CA Schiestel, S Cotell, CM Stroud, RM Stoiber, M Grabowski, KS BE Knystautas, EJ TI Ion beam processing of nanocluster-containing thin films SO MATERIALS MODIFICATION BY ION IRRADIATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Materials Modification by Ion Irradiation CY JUL 15-16, 1998 CL QUEBEC, CANADA SP SPIE Int Soc Opt Engn, Govt Canada, Govt Quebec, Greater Quebec Econ Dev Corp, INO Inst Natl Optique, Soc Innovatech Quebec Chadiere-Appalaches, Univ Laval, Quebec City, Opt Soc Amer, Flynn Rivard, Barristers & Solicitors Quebec DE ion beam assisted deposition; nanoclusters; films; nonlinear optical; photoluminescence AB We show that ion beam assisted deposition (IBAD) can result in films of metal or semiconductor nanoclusters in dielectric matrices with nonlinear optical (NLO) or photoluminescence (PL) properties. Gold nanocluster thin films (similar to 200-500 nm) consisting of metal clusters 5-30 nm in size embedded in a Nb2O5 or a SiO2 oxide matrix were deposited by ion beam assisted deposition (IBAD) by co-evaporation of Au and Nb or Si with O-2(+) ion bombardment. Semiconductor nanocluster films have been prepared by IBAD as well. Silicon-rich silica films were deposited by coevaporation of silica and silicon with and without simultaneous ion bombardment. PL attributable to defects in SiO2 was observed at about 550 nm. After annealing, the PL peak shifts to 750 nm and increases in intensity, indicating the formation of Si nanoclusters. Transmission electron microscopy (TEM) images of annealed IBAD films show a dense distribution of mostly spherically shaped crystalline Si nanoclusters, about 1-4 nm in diameter, in a featureless amorphous SiO2 matrix. TEM images of films prepared without ion assist showed many less crystalline Si clusters, that were more irregularly shaped, within 0.1 mu m amorphous silica grains. Passivation of the films with hydrogen removes the defect PL peak and enhances the peak due to nanoclusters. We have also prepared Ge nanoclusters in silica films with and without IBAD. C1 USN, Res Lab, Washington, DC 20375 USA. RP Hubler, GK (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Stroud, Rhonda/C-5503-2008; OI Stroud, Rhonda/0000-0001-5242-8015; Grabowski, Kenneth/0000-0003-0816-001X NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2867-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3413 BP 56 EP 64 DI 10.1117/12.321959 PG 9 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA BL84T UT WOS:000076922700006 ER PT J AU Jata, KV Vasudevan, AK AF Jata, KV Vasudevan, AK TI Effect of fabrication and microstructure on the fracture initiation and growth toughness of Al-Li-Cu alloys SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE Al-Li-Cu alloys; growth toughness; fracture initiation ID ALUMINUM-ALLOYS; CRACK-GROWTH AB Fracture toughness properties of three microstructural variants of aluminum-lithium alloy 2020 (4.6 Cu, 1.1 Li-0.5 Mn-0.2 Cd), were analyzed. The first variant is the base alloy, REX-2020, which is completely recrystallized, The second variant was produced by thermomechanically processing the REX-2020 and the third variant was obtained by replacing Mn in the REX-2020 by Zr, as the grain refining element. These two versions of the alloy labeled as TMP-2020 and Zr-2020, resulted in an unrecrystallized microstructure. Fracture toughness data were analyzed in terms of crack initiation toughness K-Jc, and the crack growth toughness parameter, T-R (tearing modulus). The three variants of the alloy 2020 exhibit minimum differences in both the fracture initiation toughness, K-Jc, and the crack growth toughness, T-R, in the peak aged condition. However, a considerable improvement in K-Jc is observed in the thermo mechanically processed (TMP-2020) and the Zr containing 2020 (Zr-2020) in the underaged condition. The improvement in K-Jc in the TMP-2020 and Zr-2020 variants over the REX-2020, is attributed to a higher plasticity attainable at the crack tip and finer grain size. The tearing modulus, T-R, is however higher in the REX-2020 due to planar slip and conversely the lower T-R in the TMP-2020 and Zr-2020 is due to a lower degree of planar slip than the REX-2020 alloy. The low toughness at the peak age condition in the three alloys is due to grain boundary fracture from the presence of grain boundary precipitates. There is some recovery in this lost toughness in the overaged condition where plasticity is gained via the Loss in the yield strength of the alloys. (C) 1998 Elsevier Science S.A. C1 Wright Lab, MLLM, Mat Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. Off Naval Res, Arlington, VA 22217 USA. RP Jata, KV (reprint author), Wright Lab, MLLM, Mat Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. NR 16 TC 14 Z9 14 U1 0 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN PY 1998 VL 241 IS 1-2 BP 104 EP 113 DI 10.1016/S0921-5093(97)00479-6 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA YX503 UT WOS:000072046800012 ER PT J AU Felli, JC Hazen, GB AF Felli, JC Hazen, GB TI Sensitivity analysis and the expected value of perfect information SO MEDICAL DECISION MAKING LA English DT Article DE sensitivity analysis; expected value of perfect information ID MINIMAL IMPORTANT DIFFERENCE; MONTE-CARLO SIMULATION; DECISION-ANALYSIS; MODELS AB Measures of decision sensitivity that have been applied to medical decision problems were examined. Traditional threshold proximity methods have recently been supplemented by probabilistic sensitivity analysis, and by entropy-based measures of sensitivity. The authors propose a fourth measure based upon the expected value of perfect information (EVPI), which they believe superior both methodologically and pragmatically. Both the traditional and the newly suggested sensitivity measures focus entirely on the likelihood of decision change without attention to corresponding changes in payoff, which are often small. Consequently, these measures can dramatically overstate problem sensitivity. EVPI, on the other hand, incorporates both the probability of a decision change and the marginal benefit of such a change into a single measure, and therefore provides a superior picture of problem sensitivity. To lend support to this contention, the authors revisit three problems from the literature and compare the results of sensitivity analyses using probabilistic, entropy-based, and EVPI-based measures. C1 USN, Postgrad Sch, DRMI, Monterey, CA 93943 USA. Northwestern Univ, Dept Ind Engn & Management Sci, Evanston, IL 60208 USA. RP Felli, JC (reprint author), USN, Postgrad Sch, DRMI, Code 64 FL,1522 Cunningham Rd, Monterey, CA 93943 USA. RI Hazen, Gordon/B-7463-2009 NR 40 TC 159 Z9 160 U1 0 U2 12 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 0272-989X J9 MED DECIS MAKING JI Med. Decis. Mak. PD JAN-MAR PY 1998 VL 18 IS 1 BP 95 EP 109 DI 10.1177/0272989X9801800117 PG 15 WC Health Care Sciences & Services; Medical Informatics SC Health Care Sciences & Services; Medical Informatics GA YQ612 UT WOS:000071405300017 PM 9456214 ER PT J AU Fernandez, R Galati, EB Carbajal, F Wooster, MT Watts, DM AF Fernandez, R Galati, EB Carbajal, F Wooster, MT Watts, DM TI Notes on the phlebotomine sand flies from the Peruvian southeast - I. Description of Lutzomyia (Helcocyrtomyia) adamsi n. sp. (Diptera : Psychodidae) SO MEMORIAS DO INSTITUTO OSWALDO CRUZ LA English DT Article DE Lutzomyia adamsi n. sp.; sand fly; Diptera; Psychodidae; taxonomy; Peru AB A new species of phlebotomine sand fly, Lutzomyia adamsi n. sp., is described and illustrated from specimens collected during August 1994, in Sandia, Department of Puno-Peru. According to the Oficina Nacional de Evaluacion de Recursos Naturales(ONERN 1976), this locality is situated in the life zone known as humid, mountain, low tropical forest (bh-MBT). Many areas in the northern part of Puno, mainly in the Inambari and Tambopata basins, are endemic to leishmaniasis. These areas are the continuation of others, largely known as "leishmaniasic" in the departments of Cusco and Madre de Dies. The morphological characteristics indicated that this species belongs to the genus Lutzomyia,subgenus Helcocyrtomyia Barretto, 1962. C1 USN, Med Res Inst Detachment, NAMRID, APO, AA 34031 USA. Univ Sao Paulo, Dept Epidemiol, Escola Saude Publ, Sao Paulo, SP, Brazil. RP Watts, DM (reprint author), USN, Med Res Inst Detachment, NAMRID, Unit 3800,Amer Embassy, APO, AA 34031 USA. RI GALATI, EUNICE/D-2720-2016 NR 5 TC 1 Z9 1 U1 0 U2 3 PU FUNDACO OSWALDO CRUZ PI RIO DE JANEIRO, RJ PA AV BRASIL 4365, 21045-900 RIO DE JANEIRO, RJ, BRAZIL SN 0074-0276 J9 MEM I OSWALDO CRUZ JI Mem. Inst. Oswaldo Cruz PD JAN-FEB PY 1998 VL 93 IS 1 BP 41 EP 44 DI 10.1590/S0074-02761998000100009 PG 4 WC Parasitology; Tropical Medicine SC Parasitology; Tropical Medicine GA YT211 UT WOS:000071577000009 PM 9698842 ER PT J AU Lee, HL Moran, PJ AF Lee, HL Moran, PJ TI Effects of cooling rate and annealing treatment on sensitization of austenitic-ferritic duplex stainless steel SO METALS AND MATERIALS-KOREA LA English DT Article DE duplex stainless steel; corrosion resistance; annelaing treatment; electrochemical potentiodynamic reactivation test; austenite phase; ferrite phase ID INTERGRANULAR CORROSION SUSCEPTIBILITY AB Duplex stainless steel has higher corrosion resistance and better mechanical properties than conventional type 300 series stainless steel. The corrosion behavior of duplex stainless steel is strongly dependent on the ratio, shape, size and distribution of austenite and ferrite phase in the microstructure. The relationship between the microstructure and the corrosion behavior of the duplex stainless steel was studied. For this purpose, the duplex stainless steel samples were solution heat treated at 1150 degrees C followed by either cooling at various rates (water quenching, air coooling, furnace coiling with door opened and door closed) to 820 degrees C and then water quenching to room temperature, or quenching to room temperature and annealing heat treatment at 840 degrees C for various lengths of time. A double loop electrochemical potentiodynamic reactivation (EPR) test was carried out to examine the effect of various cooling procedures or annealing treatment on the sensitization of duplex stainless steel. The grain size, shape, and distribution of the two phases were examined under microscope. From the test results, the relationships were discussed among heat treatment, electrochemical properties and microstructure. C1 ROK Naval Acad, Dept Engn Mech, Chinhae 645797, South Korea. USN Acad, Dept Mech Engn, Annapolis, MD 21401 USA. RP Lee, HL (reprint author), ROK Naval Acad, Dept Engn Mech, 88-2-3 Aengkok Dong, Chinhae 645797, South Korea. NR 6 TC 3 Z9 3 U1 0 U2 5 PU KOREAN INST METALS MATERIALS PI SEOUL PA POSCO CENTER, 4TH FL (EAST WING), 892 DAECHI-4-DONG, KANGNAM-KU, SEOUL 135-777, SOUTH KOREA SN 1225-9438 J9 MET MATER-KOREA JI Met. Mater.-Korea PY 1998 VL 4 IS 5 BP 1085 EP 1091 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 130LC UT WOS:000076520700016 ER PT J AU Elsberry, RL Carr, LE Boothe, MA AF Elsberry, RL Carr, LE Boothe, MA TI Progress toward a generalized description of the environment structure contribution to tropical cyclone track types SO METEOROLOGY AND ATMOSPHERIC PHYSICS LA English DT Article ID WESTERN NORTH PACIFIC AB A critical meteorological knowledge base for the application of the Systematic Approach to Tropical Cyclone Track Forecasting of Carr and Elsberry is the environment structure, which is a small set of synoptic patterns and synoptic regions that characterize the tracks. As the original Systematic Approach for the western North Pacific has been applied to the eastern and central North Pacific by Boothe and to the Southern Hemisphere by Bannister et al., the conceptual models of the synoptic patterns have been generalized. Whereas only slight modifications of three of the original four synoptic patterns are required in the two new basin applications, the monsoon gyre pattern of the western North Pacific must be replaced with an upper-low pattern in the eastern and central North Pacific and by a high-amplitude midlatitude trough/ridge in the Southern Hemisphere. An important conclusion is that the environment structure of all tropical cyclones in these three basins could be classified into these small sets. Furthermore, each synoptic pattern/region has a set of characteristic tracks, and a change in environment structure has an associated track change. Comparisons and contrasts of these environmental structures demonstrates that the relative importance of the monsoon trough, subtropical ridge, and midlatitude circulations can account for first-order variations in TC tracks within these three tropical cyclone basins. Summaries of the occurrence of synoptic pattern/region transitions are given for the three basins. Although each TC basin has special characteristics, the general application of the Systematic Approach suggests a unified treatment is possible. Further development along this line is expected to improve the accuracy and consistency of forecasts and warnings. C1 USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Elsberry, RL (reprint author), USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0177-7971 J9 METEOROL ATMOS PHYS JI Meteorol. Atmos. Phys. PY 1998 VL 67 IS 1-4 BP 93 EP 116 DI 10.1007/BF01277504 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 145MD UT WOS:000077374300008 ER PT J AU Leslie, LM Abbey, RF Holland, GJ AF Leslie, LM Abbey, RF Holland, GJ TI Tropical cyclone track predictability SO METEOROLOGY AND ATMOSPHERIC PHYSICS LA English DT Article ID FORECASTS; IMPACT AB In this study an attempt is made to estimate the inherent limits to tropical cyclone mean absolute track position errors out to 72 hours ahead and to compare these estimates with the position errors currently being obtained in practice at weather centres around the world. A knowledge of the magnitude of the difference between the lower limit to predictability and that being achieved with state-of-the-art numerical weather prediction (NWP) models is of vital importance. A small difference would indicate that there is little further need for continued initiatives in the prediction of tropical cyclone tracks. On the other hand, a large difference would imply either that the problem requires continued emphasis or if there has been no significant trend towards reducing the forecast track errors, that present research and development techniques need to be extended or new procedures developed. It was found that the difference between the inherent and practical limits of tropical cyclone track position errors is presently about 35 to 40 per cent for advanced baroclinic NWP systems, a moderate to large difference, and one that is almost invariant between tropical cyclone basins. For simpler models, such as barotropic models, the difference is closer to 45 per cent but is again almost invariant. As far as the authors are aware, these are the first estimates of the lower bounds of tropical cyclone track predictability. Finally, very recent research studies with emerging range of high quality data, high density data sources, improved models and new data assimilation techniques suggest that the difference possibly is now down to about 30 to 35 per cent. This value is encouragingly small but still large enough to continue active research programs in improving tropical cyclone motion prediction. Much of the forecast track errors now come from major forecast errors associated with tropical cyclones that follow erratic tracks. C1 Univ New S Wales, Sch Math, Sydney, NSW 2052, Australia. Off Naval Res, Arlington, VA 22217 USA. Bur Meteorol, Res Ctr, Melbourne, Vic 3000, Australia. RP Leslie, LM (reprint author), Univ New S Wales, Sch Math, Sydney, NSW 2052, Australia. NR 10 TC 10 Z9 10 U1 0 U2 3 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0177-7971 J9 METEOROL ATMOS PHYS JI Meteorol. Atmos. Phys. PY 1998 VL 65 IS 3-4 BP 223 EP 231 DI 10.1007/BF01030790 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZK442 UT WOS:000073321300008 ER PT J AU Bowles, J Kappus, M Antoniades, J Baumback, M Czarnaski, M Davis, CO Grossmann, J AF Bowles, J Kappus, M Antoniades, J Baumback, M Czarnaski, M Davis, CO Grossmann, J TI Calibration of inexpensive pushbroom imaging spectrometers SO METROLOGIA LA English DT Article; Proceedings Paper CT 6th International Conference on Radiometry (NEWRAD 97) CY OCT 27-29, 1997 CL TUCSON, ARIZONA ID SYSTEM AB We demonstrate the calibration and error estimation for three inexpensive pushbroom imaging spectrometers that operate in the visible/near-infrared range. The instruments were all built at the Naval Research Laboratory from commercial, off-the-shelf components. Although they are similar in basic design, their differences reflect the different objectives for which they were built. Each camera presents specific difficulties in calculating corrections to achieve uniformity and to convert to physical units. The calibration errors of one instrument are dominated by uncertainties in the integrating sphere, particularly in the short wavelength region. The errors of one of the other instruments, equipped with an intensifier, are dominated by camera noise. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. RP Bowles, J (reprint author), USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. NR 6 TC 8 Z9 8 U1 0 U2 1 PU BUREAU INT POIDS MESURES PI SEVRES CEDEX PA B1 PM PAVILLION DE BRETUEIL, F-92312 SEVRES CEDEX, FRANCE SN 0026-1394 J9 METROLOGIA JI Metrologia PY 1998 VL 35 IS 4 BP 657 EP 661 DI 10.1088/0026-1394/35/4/74 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 168NL UT WOS:000078699100074 ER PT S AU Ligler, FS Conrad, DW Golden, JP Feldstein, MJ MacCraith, BD Balderson, SD Czarnaski, J Rowe, CA AF Ligler, FS Conrad, DW Golden, JP Feldstein, MJ MacCraith, BD Balderson, SD Czarnaski, J Rowe, CA BE Gourley, PL Katzir, A TI Array biosensor for multi-analyte sensing SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS SE PROGRESS IN BIOMEDICAL OPTICS LA English DT Proceedings Paper CT Conference on Microfabricated and Nanofabricated Structures and Devices for Biomedical Environmental Applications CY JAN 26-27, 1998 CL SAN JOSE, CA SP SPIE, Int Soc Opt Engn, Int Biomed Opt Soc DE array; biosensor; fluorescence; automation; multi-analyte AB As biosensors become more sophisticated and commercially available, the general appreciation for their capabilities also increases. We now focus on multi-analyte sensors and address the problems inherent in discriminating multiple simultaneous signals without loss in assay speed, specificity or sensitivity. Furthermore, the goals of portability, simplicity and low cost have not diminished in importance. NRL is developing a multi-analyte sensor designed to be portable, inexpensive, and easy to use. To achieve these goals, we use a room temperature CCD, a diode laser, and a disposable waveguide. While our goals of using automated fluidics and automated image processing are not yet completely realized, we have fabricated a prototype biosensor which sts into a tackle box with an associated portable computer. Simple microscope slides are used as waveguides and precoated with arrays of immobilized antibodies. Fluorescence immunoassays are performed on these waveguides using as many as 6 samples at a time and assaying for up to 5 different analytes in each sample. Sensitivities in the 1-10 ng/ml range have been achieved in 10-minute assays. Initial studies in clinical fluids indicate that assays can be run on samples such as whole blood, plasma, urine, saliva and nasal secretions. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Ligler, FS (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. NR 0 TC 13 Z9 13 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 1017-2661 BN 0-8194-2697-0 J9 PROG BIOM O PY 1998 VL 3258 BP 50 EP 55 DI 10.1117/12.304363 PG 6 WC Engineering, Multidisciplinary; Engineering, Biomedical; Optics SC Engineering; Optics GA BK80K UT WOS:000073452100007 ER PT J AU Schade, SZ Yotis, WW Gopalsami, C Simonson, LG AF Schade, SZ Yotis, WW Gopalsami, C Simonson, LG TI Mitogenic activity of the outer membrane of Treponema denticola SO MICROBIOS LA English DT Article DE Treponema denticola; outer membrane; mitogenic activity; ketodeoxyoctonate; lipopolysaccharide; lipoprotein; oral spirochaetes ID SUBGINGIVAL PLAQUE; CELL-ENVELOPE; LIPOPOLYSACCHARIDE; ACID; PERIODONTITIS; ANTIGEN; ACTIVATION; CHEMISTRY; PATHOGEN; DISEASE AB The outer membrane (OM) was isolated by detergent extraction from Treponema denticola ATCC 35405, ATCC 33521 and ATCC 35404, representing serovars a, b and c, respectively, as well as from two fresh isolates of T. denticola. Strict precautions were undertaken against the introduction of contaminant lipopolysaccharide when the OM was isolated. The OM was active in mitogenic stimulation of C3H/HeOuJ mouse spleen cultures, but to a somewhat lesser extent than purified lipopolysaccharide (LPS) from Escherichia coli 055:B5. Polymyxin B only partially inhibited the response. Unheated OM abrogated mitogenic activity of E. coli LPS, but heated preparations enhanced the mitogenic activity of E. coli LPS, suggesting the presence of a heat-labile cytolytic factor associated with T: denticola OM in addition to a putative lipopolysaccharide and/or heat-stable lipoprotein. C1 USN, Inst Dent Res, Dept Appl Lab Sci, Great Lakes, IL 60088 USA. Loyola Univ, Stritch Sch Med, Dept Microbiol & Immunol, Maywood, IL 60153 USA. Loyola Univ, Med Ctr, Dept Otolaryngol Head & Neck Surg, Maywood, IL 60153 USA. RP Schade, SZ (reprint author), USN, Inst Dent Res, Dept Appl Lab Sci, Great Lakes, IL 60088 USA. NR 35 TC 1 Z9 1 U1 0 U2 0 PU FACULTY PRESS PI CAMBRIDGE PA 88 REGENT ST, CAMBRIDGE, CAMBS, ENGLAND CB2 1DP SN 0026-2633 J9 MICROBIOS JI Microbios PY 1998 VL 96 IS 383 BP 51 EP 63 PG 13 WC Microbiology SC Microbiology GA 164QR UT WOS:000078475500005 PM 10347901 ER PT J AU Christianson, KA AF Christianson, KA TI Reliability of III-V based heterojunction bipolar transistors SO MICROELECTRONICS AND RELIABILITY LA English DT Review ID 1/F NOISE SOURCES; FREQUENCY NOISE; SURFACE PASSIVATION; DOPED BASE; HBTS; GAAS; PERFORMANCE; CONDUCTION; SIMULATION; CIRCUITS AB This paper reviews the reliability of III-V based heterojunction bipolar transistors (HBTs). These devices have many potential advantages over other solid-state microwave devices. However, because of the tradeoff between performance and reliability, they are not being used to any great extent in power microwave applications. In the type of III-V HBT device most fully developed, the AlGaAs/GaAs HBT, leakage currents play a major role in the dominant mode of degradation. Because low-frequency noise is related to these leakage currents it has been used extensively in the analysis of the performance and reliability limitations of these devices. The reliability of other types of III-V HBT devices, such as InGaP/GaAs and InP based devices, is also discussed. (C) 1998 Published by Elsevier Science Ltd. C1 USN, Res Lab, Washington, DC 20375 USA. RP Christianson, KA (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 47 TC 3 Z9 3 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0026-2714 J9 MICROELECTRON RELIAB JI Microelectron. Reliab. PD JAN PY 1998 VL 38 IS 1 BP 153 EP 161 DI 10.1016/S0026-2714(97)00070-X PG 9 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA ZE234 UT WOS:000072771600015 ER PT S AU Rife, JC Bell, MI AF Rife, JC Bell, MI BE Frazier, AB Ahn, CH TI Acousto- and electroosmotic microfluidic controllers SO MICROFLUIDIC DEVICES AND SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Microfluidic Devices and Systems CY SEP 21-22, 1998 CL SANTA CLARA, CA SP SPIE DE fluidics; microfluidics; pumps; acoustic; acoustic streaming; electrokinetic; electroosmosis; ultrasonic AB Acoustic and electroosmotic uni-directional pumping mechanisms for single and multichannel valve-less fluidic pumps and controllers are compared. Geometry, scaling, efficiency and heating, fluid restrictions, and wall materials for the mechanisms are analyzed. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rife, JC (reprint author), USN, Res Lab, Code 6680, Washington, DC 20375 USA. NR 0 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2974-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3515 BP 125 EP 135 DI 10.1117/12.322074 PG 11 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Fluids & Plasmas SC Engineering; Instruments & Instrumentation; Physics GA BL77P UT WOS:000076705100013 ER PT J AU Robinson, GE AF Robinson, GE TI Elite cohesion, regime succession and political instability in Syria SO MIDDLE EAST POLICY LA English DT Article C1 USN, Postgrad Sch, Monterey, CA 93940 USA. Univ Calif Berkeley, Ctr Middle Eastern Studies, Berkeley, CA 94720 USA. RP Robinson, GE (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 16 TC 5 Z9 5 U1 0 U2 2 PU MIDDLE EAST POLICY COUNCIL PI WASHINGTON PA 1730 M ST, NW, STE 512, WASHINGTON, DC 20036 USA SN 1061-1924 J9 MIDDLE EAST POLICY JI Middle East Policy PD JAN PY 1998 VL 5 IS 4 BP 159 EP 179 PG 21 WC Area Studies; International Relations SC Area Studies; International Relations GA YU932 UT WOS:000071771100012 ER PT J AU Cullison, TR O'Brien, TJ Getka, K Jonson, S AF Cullison, TR O'Brien, TJ Getka, K Jonson, S TI Anterior cruciate ligament reconstruction in the military patient SO MILITARY MEDICINE LA English DT Article ID FUNCTIONAL DISABILITY; DEFICIENT KNEE; REHABILITATION; TEARS AB This study prospectively evaluates the likelihood of a return of military personnel to full duty after anterior cruciate ligament reconstruction. We report the results of 120 active duty military patients who underwent anterior cruciate ligament reconstruction with autogenous patella tendon. Mean follow-up was 29 months (range, 24-65 months), Time from injury to reconstruction was >6 months in 90% of patients. Final Lysholm scores averaged 89 (range, 29-100). We found that 77% of patients returned to full duty, whereas 23% of patients were medically discharged from military service, The patient age, military rank, time from injury to surgery, and KT-1000 measurements did not correlate with either the Lysholm score or return to duty (p = 0.05). Severe chondromalacia (Outerbridge hi or IV) did correlate with poor result (p = 0.043), and Lysholm score did correlate with return to duty (p = 0.003), Anterior cruciate ligament reconstruction offers a higher likelihood of return to full military duty than nonoperative treatment in a similar study. C1 USN, Med Ctr, Dept Orthoped, San Diego, CA 92152 USA. RP Cullison, TR (reprint author), USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. NR 18 TC 4 Z9 4 U1 1 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD JAN PY 1998 VL 163 IS 1 BP 17 EP 19 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA YT022 UT WOS:000071556200006 PM 9465566 ER PT J AU Chung-Park, MS AF Chung-Park, MS TI Perception of the nurse practitioner's role and job satisfaction in the United States Navy SO MILITARY MEDICINE LA English DT Article ID WORK AB A few studies have specifically examined the role perception and job satisfaction of civilian nurse practitioners (NPs), but no data exist for U.S. Navy NPs. The purpose of this study was to describe the perceptions of the Navy NP's roles by commanding officers, directors of nursing services, physicians, and NPs, and the level of job satisfaction among Navy NPs. A total of 907 questionnaires investigating NP role and job satisfaction were mailed to 29 Naval hospitals and clinics in the United States and overseas. The sample size totaled 450 (50% response rate). Of the 450 respondents, 45 NPs also filled out the Measure of Job Satisfaction survey. There were measurable differences in NP role perception by the sample groups. Role conflict and ambiguity were shown. Autonomy, sense of accomplishment, and time spent in patient care were major satisfiers, whereas pay, overall staffing levels, time available to get through work, and the amount of time spent on administrative work were the major dissatisfiers. C1 USN, Med Ctr, Dept Obstet Gynecol, San Diego, CA 92152 USA. RP Chung-Park, MS (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 21 TC 7 Z9 7 U1 1 U2 2 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD JAN PY 1998 VL 163 IS 1 BP 26 EP 32 PG 7 WC Medicine, General & Internal SC General & Internal Medicine GA YT022 UT WOS:000071556200008 PM 9465568 ER PT J AU Konoske, PJ Dobbins, RW Gauker, ED AF Konoske, PJ Dobbins, RW Gauker, ED TI MARC ES: A computer program for estimating medical information storage requirements SO MILITARY MEDICINE LA English DT Article AB During combat, documentation of medical treatment information is critical for maintaining continuity of patient care. However, knowledge of prior status and treatment of patients is limited to the information noted on a paper field medical card. The Multi-technology Automated Reader Card (MARC), a smart card, has been identified as a potential storage mechanism for casualty medical information. Focusing on data capture and storage technology, this effort developed a Windows program, MARC ES, to estimate storage requirements for the MARC. The program calculates storage requirements for a variety of scenarios using medical documentation requirements, casualty rates, and casualty flows and provides the user with a tool to estimate the space required to store medical data at each echelon of care for selected operational theaters. The program can also be used to identify the point at which data must be uploaded from the MARC if size constraints are imposed. Furthermore, this model can be readily extended to other systems that store or transmit medical information. C1 USN, Med Informat Syst & Operat Res Dept, San Diego, CA 92186 USA. RP Konoske, PJ (reprint author), USN, Med Informat Syst & Operat Res Dept, POB 85122, San Diego, CA 92186 USA. NR 8 TC 1 Z9 1 U1 1 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD JAN PY 1998 VL 163 IS 1 BP 49 EP 55 PG 7 WC Medicine, General & Internal SC General & Internal Medicine GA YT022 UT WOS:000071556200013 PM 9465573 ER PT J AU Jahn, TW AF Jahn, TW TI Septic arthritis and calcium pyrophosphate deposition disease in the setting of chronic gout SO MILITARY MEDICINE LA English DT Article ID CRYSTAL AB Septic arthritis is a medical and surgical emergency that if left untreated may lead to permanent joint disfigurement and loss of function, In the setting of chronic joint disease, the diagnosis, based on history and physical examination, may be difficult, A case is reported of a patient with a history of aspirate-proven gout presenting with symptoms of typical gouty exacerbation but diagnosed as septic arthritis and pseudogout. C1 USN, Med Ctr, Dept Emergency Med, San Diego, CA USA. RP Jahn, TW (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 8 TC 3 Z9 3 U1 1 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD JAN PY 1998 VL 163 IS 1 BP 61 EP 62 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA YT022 UT WOS:000071556200016 PM 9465576 ER PT J AU Merrill, LL Hervig, LK Milner, JS Newell, CE Koss, MP AF Merrill, LL Hervig, LK Milner, JS Newell, CE Koss, MP TI Premilitary intimate partner conflict resolution in a navy basic trainee sample SO MILITARY PSYCHOLOGY LA English DT Article ID COURTSHIP VIOLENCE; GENDER DIFFERENCES; AGGRESSION; WOMEN; SEX AB This study investigated the rates of intimate partner verbal and physical violence (inflicted and received) and the rates of physical injury inflicted by the intimate partner that were reported by 2,987 female and male Navy basic trainees who voluntarily completed self-report questionnaires during the first week of training. The rates of intimate partner physical violence reported by the trainees were at the upper end of the range of rates reported by college students. More female (46.9%) than male (31.9%) trainees reported at least one instance of inflicting physical violence. In addition to a higher absolute frequency of physical violence, women reported significantly higher physical violence scores, which indicated that women used physical violence at a higher rate than men. Nevertheless, substantially more women (24.9%) than men (9.0%) reported being physically injured by an intimate partner, supporting the view that the consequences of intimate partner physical violence are more serious for women. C1 USN, Hlth Res Ctr, San Diego, CA 92186 USA. No Illinois Univ, Dept Psychol, De Kalb, IL 60115 USA. Univ Arizona, Dept Family & Community Med, Tucson, AZ 85721 USA. RP Merrill, LL (reprint author), USN, Hlth Res Ctr, POB 85122, San Diego, CA 92186 USA. NR 25 TC 12 Z9 12 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 1 BP 1 EP 15 DI 10.1207/s15327876mp1001_1 PG 15 WC Psychology, Multidisciplinary SC Psychology GA YV828 UT WOS:000071867400001 ER PT J AU Borack, JI AF Borack, JI TI An estimate of the impact of drug testing on the deterrence of drug use SO MILITARY PSYCHOLOGY LA English DT Article AB This study developed an estimate of the ability of the Navy's drug testing program to deter drug use. Drug use in the Navy was compared to comparable groups of civilians over time in order to determine the impact of testing. Deterrence was defined as the proportion of drug users in the Navy (individuals who would use drugs at least once during a 30-day period) who no longer would use drugs if testing were conducted at a specific monthly test rate (e.g., 20%). Findings indicated that drug testing at present levels deters almost 60% of potential drug use. C1 USN, Ctr Personnel Res & Dev, San Diego, CA 92152 USA. RP Borack, JI (reprint author), USN, Ctr Personnel Res & Dev, Code 11,53335 Ryne Rd, San Diego, CA 92152 USA. NR 13 TC 5 Z9 5 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 1 BP 17 EP 25 DI 10.1207/s15327876mp1001_2 PG 9 WC Psychology, Multidisciplinary SC Psychology GA YV828 UT WOS:000071867400002 ER PT J AU Thomas, PJ Rosenfeld, P AF Thomas, PJ Rosenfeld, P TI Special issue: Equal opportunity research in the US Military - Preface to the special issue SO MILITARY PSYCHOLOGY LA English DT Editorial Material ID NAVY C1 USN, Ctr Personnel Res & Dev, San Diego, CA 92152 USA. RP Rosenfeld, P (reprint author), USN, Ctr Personnel Res & Dev, Code 122,53335 Ryne Rd, San Diego, CA 92152 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 2 BP 63 EP 67 PG 5 WC Psychology, Multidisciplinary SC Psychology GA ZJ443 UT WOS:000073216200001 ER PT J AU Rosenfeld, P Newell, CE Le, S AF Rosenfeld, P Newell, CE Le, S TI Equal opportunity climate of women and minorities in the Navy: Results from the Navy Equal Opportunity Sexual Harassment (NEOSH) Survey SO MILITARY PSYCHOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Psychological-Association CY AUG, 1995 CL WASHINGTON, D.C. SP Amer Psychol Assoc AB This article reviews the equal opportunity (EO) climate of women and minorities in the Navy based on the results of the 1993 Navy Equal Opportunity/Sexual Harassment (NEOSH) Survey. A random sample of active-duty Navy officers and enlisted personnel stratified by racial and ethnic group (White/Other, Black, and Hispanic) and gender was selected, resulting in 12 groups (N = 3,801; response rate = 41%). The data were weighted to reflect the actual distribution of the 12 groups in the Navy population. Results indicated that overall Navy EO climate is positive; however, the perceptions of women and Blacks were generally less positive than those of men and Whites. Specific findings on racial and gender discrimination are discussed. Overall, the results show that those who have experienced racial or gender discrimination are less satisfied with the Navy, have higher intentions of leaving, and lower intentions to remain in the Navy until retirement. Comparisons between 1991 and 1993 findings showed evidence of widening perceptual gaps between Whites and minorities and between men and women, especially among officers. Implications of these results are discussed. C1 USN, Ctr Personnel Res & Dev, San Diego, CA 92152 USA. USN, Hlth Res Ctr, San Diego, CA 92152 USA. RP Rosenfeld, P (reprint author), USN, Ctr Personnel Res & Dev, Code 122,53335 Ryne Rd, San Diego, CA 92152 USA. NR 23 TC 13 Z9 13 U1 0 U2 1 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 2 BP 69 EP 85 DI 10.1207/s15327876mp1002_1 PG 17 WC Psychology, Multidisciplinary SC Psychology GA ZJ443 UT WOS:000073216200002 ER PT J AU Thomas, PJ Edwards, JE Perry, ZA David, KM AF Thomas, PJ Edwards, JE Perry, ZA David, KM TI Racial differences in male Navy officer fitness reports SO MILITARY PSYCHOLOGY LA English DT Article ID PERFORMANCE EVALUATIONS; RACE; RATINGS AB The perception of racial bias in performance evaluation is widespread among Black male Navy officers. In this article, we discuss an analysis of the quantitative marks and written comments in the fitness reports of matched pairs of 582 officers. Ninety-nine percent of the White officers and 96% of the Black officers were rated in the highest block on overall performance. Some racial differences were found in the written comments, however. White officers were described as outstanding leaders more often than Black officers. Most important, White officers were given significantly more promotion-related recommendations than were Black officers, who received more assignment-related recommendations. There were virtually no racial differences in the evaluations of pilots and naval flight officers. Black officers in the surface warfare community and medical service corps, the communities having the highest population of Black officers, were apt to receive less career-enhancing ratings than their White peers. The analysis by military rank revealed that most of the racial differences occurred in the evaluations of lieutenants. Because information concerning actual level of performance was unavailable, it was not possible to conclude that racial bias was operating. C1 USN, Ctr Personnel Res & Dev, San Diego, CA 92152 USA. Def Manpower Data Ctr, Arlington, VA USA. San Diego State Fdn, San Diego, CA USA. RP Perry, ZA (reprint author), USN, Ctr Personnel Res & Dev, 53335 Ryne Rd, San Diego, CA 92152 USA. NR 15 TC 4 Z9 4 U1 1 U2 1 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 2 BP 127 EP 143 DI 10.1207/s15327876mp1002_4 PG 17 WC Psychology, Multidisciplinary SC Psychology GA ZJ443 UT WOS:000073216200005 ER PT J AU Schwerin, MJ Corcoran, KJ AF Schwerin, MJ Corcoran, KJ TI Discriminant analysis of medical-care use among shipboard US navy men and women SO MILITARY PSYCHOLOGY LA English DT Article ID SEX-DIFFERENCES; HEALTH BELIEFS; CHECKS AB A matched sample of men and women in the U.S. Navy (N = 1,068) were examined in a study of shipboard medical-care use. The instrument used in this study is theoretically based on the Health Beliefs Model (HBM). Theoretically, the HEM attempts to explain health-seeking behavior by describing the antecedent conditions within the individual. Preliminary chi-square results indicate statistically significant gender differences in health-care use. Separate discriminant function analyses were employed for men and women. Results for each separate discriminant function analysis yielded a single statistically significant function for female crewmembers only. Univariate F-ratio results between female medical users and nonusers show that users have significantly higher ratings of health value, health comparison, and "reason" barriers (e.g., "I already see the doctor a lot"). Male users and nonusers differ in that users have significantly higher ratings of medical-care satisfaction, whereas nonusers have significantly higher "motivation" barriers. Implications of these findings and the efficacy of the HEM are discussed. C1 USN, Hlth Res Ctr, San Diego, CA 92152 USA. So Illinois Univ, Dept Psychol, Carbondale, IL 62901 USA. RP Schwerin, MJ (reprint author), USN, Personnel Command, Navy Equal Opportun Div Pers 61R, 7800 3rd St,Bldg 457, Millington, TN 38054 USA. NR 17 TC 1 Z9 1 U1 2 U2 3 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 3 BP 147 EP 158 DI 10.1207/s15327876mp1003_1 PG 12 WC Psychology, Multidisciplinary SC Psychology GA ZY495 UT WOS:000074627500001 ER PT J AU Dyer, JL Mittelman, MH AF Dyer, JL Mittelman, MH TI Evaluation of an unaided night vision instructional program for ground forces SO MILITARY PSYCHOLOGY LA English DT Article ID STUDENTS AB As military night operations become increasingly important and night vision devices proliferate, soldiers must still know how to use their eyes effectively. An instructional program using neutral density filters on 35-mm slides to demonstrate phenomena typical of night vision was developed and evaluated. The slide version of the program increased test scores of infantrymen by 40% regardless of time served in the Army. With infantry trainees, the slide version and a text version had positive, yet similar, effects on immediate and retention tests. Although the slides benefited trainees with low general ability, the text benefited trainees with higher general ability. The findings reinforce the need for a more complete understanding of how individuals process perceptual information critical to night operations and how instructional materials in this area should be developed. C1 USA, Res Inst, Infantry Forces Res Unit, Ft Benning, GA 31995 USA. USN, Aerosp Med Res Lab, Pensacola, FL USA. RP Dyer, JL (reprint author), USA, Res Inst, Infantry Forces Res Unit, POB 52086, Ft Benning, GA 31995 USA. NR 24 TC 0 Z9 0 U1 1 U2 1 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 3 BP 159 EP 172 DI 10.1207/s15327876mp1003_2 PG 14 WC Psychology, Multidisciplinary SC Psychology GA ZY495 UT WOS:000074627500002 ER PT J AU Bowers, C Thornton, C Braun, C Morgan, BB Salas, E AF Bowers, C Thornton, C Braun, C Morgan, BB Salas, E TI Automation, task difficulty, and aircrew performance SO MILITARY PSYCHOLOGY LA English DT Article AB The effects of an automated system on team processes and performance were assessed in a laboratory simulation. Two-person crews were required to fly a complex emergency-response scenario under conditions of low and high workload. These flights were completed with or without the aid of an autopilot. The results indicated that the autopilot was effective in reducing subjective workload. However, the automation was associated with improved performance on only 1 of 4 performance measures. Furthermore, it was observed that problem-solving performance was worse in the autopilot condition during the high-workload flights. Investigation of crew process data indicated that workload savings afforded by the autopilot might have been invested in more explicit coordination. The results are discussed in terms of their implications for military aviators' performance, system design, and team training. C1 Univ Cent Florida, Dept Psychol, Orlando, FL 32816 USA. Old Dominion Univ, Dept Psychol, Norfolk, VA 23529 USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. RP Bowers, C (reprint author), Univ Cent Florida, Dept Psychol, Orlando, FL 32816 USA. NR 31 TC 2 Z9 2 U1 1 U2 1 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 4 BP 259 EP 274 DI 10.1207/s15327876mp1004_3 PG 16 WC Psychology, Multidisciplinary SC Psychology GA 137TL UT WOS:000076932200004 PM 11541776 ER PT S AU Socker, DG AF Socker, DG BE Korendyke, CM TI Stereographic image potential of a STEREO mission SO MISSIONS TO THE SUN II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on the Missions to the Sun II CY JUL 22-23, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE solar terrestrial observatory mission; solar physics; heliospheric physics AB The potential quality increase of the scientific results obtainable with stereographic observations on a Solar-TErrestrial Relations Observatory (STEREO) mission are examined in terms of the science objectives, observables, instrument performance, spacecraft vantage points and stereographic image reconstruction. The basic scientific objectives of a STEREO mission addressable with stereographic techniques are grouped into classes based on the nature of their observable attributes. To keep the discussion tractable, we select one of the scientific objectives, the study of coronal mass ejections, to illustrate the advantages of observation from two vantage points. Movies developed from solar observations obtained with the Solar Heliospheric Observatory (SOHO) are presented to graphically illustrate the advantages of two vantage point observations. Next a possible set of stereographic instruments, along with their requirements and performance limitations is presented listed. Optimal stereographic vantage points for the instruments, assuming a two spacecraft mission, realistic orbits and telemetry rates are then considered. C1 USN, Res Lab, Washington, DC 20375 USA. RP Socker, DG (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2897-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3442 BP 44 EP 52 DI 10.1117/12.330263 PG 9 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BM19X UT WOS:000078010300005 ER PT S AU Korzeniowski, KA McVey, CB AF Korzeniowski, KA McVey, CB BE Choset, HM Gage, DW Kachroo, P Kourjanski, MA deVries, MJ TI A hierarchical system for automated path planning and scheduling SO MOBILE ROBOTS XIII AND INTELLIGENT TRANSPORTATION SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Mobile Robots XIII and Intelligent Transportation Systems CY NOV 03-05, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, Soc Mfg Engineers DE navigation; temporal planning; generative planner; artificial intelligence; multi-agent coordination ID SPACE AB This paper describes a hierarchical system for dynamic path planning and scheduling among a field of moving obstacles. The solution is directly applicable to many autonomous navigation scenarios, such as movement on a manufacturing floor, navigation of surface/subsurface ships or coordination of air traffic. The overall system is discussed in terms of global/local perception and generative planning/reactive control. The development and implementation of the generative planner portion of the existing system are described in detail. In terms of real-time system performance, the multi-dimensional search problem is made tractable by applying two dependent 2-D techniques in series. First, the shortest distance, obstacle-avoiding path to the goal is calculated, then for that path, the time to the goal is optimized. In this space-time representation of the domain, time requirements can be imposed upon the goal(s) and therefore scheduling can also be accomplished. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21403 USA. RP Korzeniowski, KA (reprint author), USN Acad, Dept Elect Engn, Annapolis, MD 21403 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2986-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3525 BP 204 EP 211 PG 8 WC Automation & Control Systems; Engineering, Manufacturing; Optics; Transportation SC Automation & Control Systems; Engineering; Optics; Transportation GA BM42S UT WOS:000078690700020 ER PT S AU Gage, DW AF Gage, DW BE Choset, HM Gage, DW Kachroo, P Kourjanski, MA deVries, MJ TI An evolutionary strategy for achieving autonomous navigation SO MOBILE ROBOTS XIII AND INTELLIGENT TRANSPORTATION SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Mobile Robots XIII and Intelligent Transportation Systems CY NOV 03-05, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, Soc Mfg Engineers DE mobile robot; autonomous navigation; visual servoing AB An approach is presented for the evolutionary development of supervised autonomous navigation capabilities for small "backpackable" ground robots, in the context of a DARPA-sponsored program to provide robotic support to small units of dismounted warfighters. This development approach relies on the implementation of a baseline visual servoing navigation capability, including tools to support operator oversight and override, which is then enhanced with semantically referenced commands and a mission scripting structure. As current and future machine perception techniques are able to automatically designate visual servoing goal points, this approach should provide a natural evolutionary pathway to higher levels of autonomous operation and reduced requirements for operator intervention. C1 USN, Space & Warfare Syst Ctr San Diego, SPAWARSYSCEN D371, San Diego, CA 92152 USA. RP Gage, DW (reprint author), USN, Space & Warfare Syst Ctr San Diego, SPAWARSYSCEN D371, San Diego, CA 92152 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2986-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3525 BP 252 EP 260 PG 9 WC Automation & Control Systems; Engineering, Manufacturing; Optics; Transportation SC Automation & Control Systems; Engineering; Optics; Transportation GA BM42S UT WOS:000078690700025 ER PT S AU Kang, W Xi, N Fitch, O AF Kang, W Xi, N Fitch, O BE Choset, HM Gage, DW Kachroo, P Kourjanski, MA deVries, MJ TI Mobile robot tracking control in a perceptive frame SO MOBILE ROBOTS XIII AND INTELLIGENT TRANSPORTATION SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Mobile Robots XIII and Intelligent Transportation Systems CY NOV 03-05, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, Soc Mfg Engineers DE action reference; tracking control; autonomous vehicle AB A new design method for non-time based tracking controller is presented. The key to the non-time based control method is the, introduction of a suitable action or motion reference variable other than time, which is directly related to the desired and measurable system output. It enables the construction of control systems with integrated planning capability, in which planning becomes real-time closed-loop process. The new design method converts a controller designed by traditional time-based approach to a non-time based controller using action reference. It significantly simplifies the design procedure. The design method is exemplified by a unmanned vehicle tracking control problem. The design procedure and simulation results demonstrate the advantages of proposed method. C1 USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. RP Kang, W (reprint author), USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2986-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3525 BP 274 EP 284 PG 11 WC Automation & Control Systems; Engineering, Manufacturing; Optics; Transportation SC Automation & Control Systems; Engineering; Optics; Transportation GA BM42S UT WOS:000078690700027 ER PT J AU Broughton, JQ Gilmer, GH AF Broughton, JQ Gilmer, GH TI Grain-boundary shearing as a test for interface melting SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID MOLECULAR-DYNAMICS; SIMULATION; TRANSITION; MODEL; SEGREGATION; SURFACES; CRYSTAL; METALS; FILMS AB We examine the behaviour of the (310) symmetric tilt boundary with applied shear stress in a face-centred cubic Lennard-Jones crystal. Our purpose is to observe the mechanical properties of grain boundaries resulting from interface melting. The grain boundary is seen to exhibit significant self-diffusion at temperatures above 80% of the bulk melting point (T-m). Excess thermodynamic properties and the density of the system change dramatically in this region. However, the system is able to resist shear up to the higher temperature of 0.96T(m). Plots of particle trajectories in the interface and estimates of the number of melted layers provide insight into an understanding of this behaviour. C1 USN, Res Lab, Washington, DC 20375 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Broughton, JQ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 33 TC 19 Z9 20 U1 2 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JAN PY 1998 VL 6 IS 1 BP 87 EP 97 DI 10.1088/0965-0393/6/1/008 PG 11 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA ZA436 UT WOS:000072363100008 ER PT B AU Vego, M AF Vego, M BE Crickard, FW Mitchell, PT Orr, K TI Multinational naval cooperation in the Middle East and Mediterranean: Problems and prospects SO MULTINATIONAL NAVAL COOPERATION AND FOREIGN POLICY INTO THE 21ST CENTURY LA English DT Proceedings Paper CT Conference on Multinational Naval Cooperation and Foreign Policy into the 21st Century CY MAY, 1996 CL HALIFAX, CANADA SP Dalhousie Univ, Ctr Foreign Policy Studies, NATO, Allied Command, Canada Maritime Command, US Atlantic Fleet, USN, Doctrine Command C1 USN, War Coll, Joint Mil Operat Dept, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASHGATE PUBLISHING LTD PI ALDERSHOT PA GOWER HOUSE, CROFT ROAD, ALDERSHOT GU11 3HR, ENGLAND BN 1-85521-997-2 PY 1998 BP 195 EP 219 PG 25 WC Economics; Political Science SC Business & Economics; Government & Law GA BL82J UT WOS:000076836800011 ER PT B AU Breemer, JS AF Breemer, JS BE Crickard, FW Mitchell, PT Orr, K TI Security in northern waters: A new Nordic balance? SO MULTINATIONAL NAVAL COOPERATION AND FOREIGN POLICY INTO THE 21ST CENTURY LA English DT Proceedings Paper CT Conference on Multinational Naval Cooperation and Foreign Policy into the 21st Century CY MAY, 1996 CL HALIFAX, CANADA SP Dalhousie Univ, Ctr Foreign Policy Studies, NATO, Allied Command, Canada Maritime Command, US Atlantic Fleet, USN, Doctrine Command C1 USN, Postgrad Sch, Monterey, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ASHGATE PUBLISHING LTD PI ALDERSHOT PA GOWER HOUSE, CROFT ROAD, ALDERSHOT GU11 3HR, ENGLAND BN 1-85521-997-2 PY 1998 BP 220 EP 232 PG 13 WC Economics; Political Science SC Business & Economics; Government & Law GA BL82J UT WOS:000076836800012 ER PT B AU Chow, GM AF Chow, GM BE Chow, GM Noskova, NI TI Chemical synthesis and processing of nanostructured particles and coatings SO NANOSTRUCTURED MATERIALS: SCIENCE & TECHNOLOGY SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 3, HIGH TECHNOLOGY LA English DT Proceedings Paper CT NATO Advanced Study Institute on Nanostructured Materials - Science and Technology CY AUG 10-20, 1997 CL ST PETERSBURG, RUSSIA SP NATO, Sci Comm, NATO, High Technol Area Program, USN, Off Naval Res, US Natl Sci Fdn, Russian Acad Sci, Russian Fdn Basic Res, Amer Soc Engn Educ, Adv Mat & Technol Fdn, Russia AB An overview of the synthesis and processing of nanostructured particles and coatings using chemical routes is presented. Solution chemistry approaches offer advantages of the design of materials at the molecular level that can result in better homogeneity for multiphase materials, and cost-efficient bulk quantity production in many cases. Of particular importance, solution chemistry allows for the control of particle size and particle size distribution, and the control of agglomerate size and agglomerate size distribution, through effective manipulation of the parameters determining nucleation, growth and agglomeration at the molecular level. In this paper, selected examples of metallic, ceramic and hybrid materials prepared by aqueous, nonaqueous, sol-gel and surfactant mediated methods are given. The effects of the synthesis and processing conditions on the phases, microstructures, control of particle size and agglomeration, impurities incorporation, defects formation and properties are addressed. C1 USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. RP Chow, GM (reprint author), USN, Res Lab, Div Mat Sci & Technol, Code 6323, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5071-5 J9 NATO ASI 3 HIGH TECH PY 1998 VL 50 BP 31 EP 46 PG 16 WC Engineering, Multidisciplinary; Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BL42D UT WOS:000075454000003 ER PT B AU Provenzano, V AF Provenzano, V BE Chow, GM Noskova, NI TI Nanostructured materials for gas-reactive applications SO NANOSTRUCTURED MATERIALS: SCIENCE & TECHNOLOGY SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 3, HIGH TECHNOLOGY LA English DT Proceedings Paper CT NATO Advanced Study Institute on Nanostructured Materials - Science and Technology CY AUG 10-20, 1997 CL ST PETERSBURG, RUSSIA SP NATO, Sci Comm, NATO, High Technol Area Program, USN, Off Naval Res, US Natl Sci Fdn, Russian Acad Sci, Russian Fdn Basic Res, Amer Soc Engn Educ, Adv Mat & Technol Fdn, Russia AB Nanostructured materials with their small grain size, large number of grain boundaries and surfaces, together with their strong reactivity with gaseous species, are very interesting materials to study and develop for gas-reactive applications. These applications include: gas-sensors and getters and hydrogen storage. In this chapter, the basic characteristics of nanostructured materials, especially those related to gas reactions will be presented. This will be followed by a review of the research activities on nanostructured materials in gas sensors, getters, and hydrogen storage devices. The chapter will conclude by briefly discussing the challenges and the opportunities associated with this very interesting and promising area of research. C1 USN, Res Lab, Div Mat Sci & Technol, Phys Met Branch, Washington, DC 20375 USA. RP Provenzano, V (reprint author), USN, Res Lab, Div Mat Sci & Technol, Phys Met Branch, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5071-5 J9 NATO ASI 3 HIGH TECH PY 1998 VL 50 BP 335 EP 359 PG 25 WC Engineering, Multidisciplinary; Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BL42D UT WOS:000075454000017 ER PT J AU Walters, JD Sondergaard, NA Levedahl, J Waltman, D Golda, EM Fikse, TH AF Walters, JD Sondergaard, NA Levedahl, J Waltman, D Golda, EM Fikse, TH TI Reexamination of superconductive homopolar motors for propulsion SO NAVAL ENGINEERS JOURNAL LA English DT Article AB Superconducting homopolar motor concepts with accompanying auxiliary systems have been examined in a quick-look assessment for their impact on ship designs utilizing the Navy's Advanced Surface Ship Evaluation Tool (ASSET) developed by the Naval Surface Warfare Center Carderock Division. An existing ASSET DDG51-FLT2A "like" ship model was used as a convenient means of evaluating the ship impact of the superconducting homopolar, and other advanced electric propulsion systems. For simplicity, all ship impact benefits due to increased power density and efficiency are taken in increased fuel capacity and thus, increased ship operating range. Previous studies have shown that superconducting homopolar motors are well suited to Navy propulsion systems due to their inherent low noise generation, high power density, and efficiency Homopolar motors are the only true direct current electrical motors and produce very smooth torque because they have no magnetic field pulsations or alternating currents. The Annapolis Laboratory of the Naval Surface Warfare Center is reexamining superconducting homopolar motor technology in light of the resurgent interest in a more electric Navy and because of significant advancements in two key homopolar component technologies. Extensive development of mechanical cryogenic refrigerators has resulted in liquid cryogen-free superconducting magnets. Magnet systems utilizing cryogen-free technology have been kept at superconducting temperatures for over two years (18,000 hrs.) with no maintenance. Development of dry copper-fiber and multiple-foil copper brushes has eliminated the need for liquid metal current collectors used in early homopolar motors. Basic wear measurements imply replacement times of tens of thousands of full-power motor hours. Superconductive homopolar motor designs utilizing the new solid collectors are comparable in size to those for previous designs, and show only small increases in machine size as voltage increases from 200V to 2,000V. As a result, the operating voltage of a homopolar machine can now be selected on an overall system basis in the same way as conventional alternating current systems. Advances in these key technologies and the promising results of the ship impact assessments indicate that a closer examination of superconducting homopolar motors for propulsion is warranted. C1 USN, Ctr Surface Warfare, Annapolis Detachment, Elect Machinery Technol Branch, Washington, DC 20350 USA. RP Walters, JD (reprint author), USN, Ctr Surface Warfare, Annapolis Detachment, Elect Machinery Technol Branch, Washington, DC 20350 USA. NR 27 TC 6 Z9 6 U1 0 U2 4 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD JAN PY 1998 VL 110 IS 1 BP 107 EP 116 PG 10 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA ZD960 UT WOS:000072743000008 ER PT J AU Nisenoff, M Price, G Gubser, DU Ritter, JC Wolf, SA AF Nisenoff, M Price, G Gubser, DU Ritter, JC Wolf, SA TI The High Temperature Superconductivity Space Experiment: Present status and future challenges SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The High Temperature Superconductivity Space Experiment (HTSSE) at the Naval Research Laboratory (NRL) is exploring the feasibility of deploying high temperature superconducting (HTS) electronic devices, components and subsystems in space. The initial HTSSE experiment, which employed HTS technology available in 1990, focused on simple microwave devices which were suitably packaged, integrated with a cryogenic refrigerator and built into a space-qualified payload. Unfortunately the HTSSE-I payload, which was to have been launched in 1993, did not achieve orbit and was lost. The second HTSSE experiment, HTSSE-II, which employs HTS technology circa 1993-94, consists of complex HTS components and hybrid subsystems consisting of HTS and conventional semiconductor components, the latter operating either at cryogenic temperature or at room temperature. The HTSSE-II payload containing the HTS components, cryogenic refrigerator and monitoring electronics was built, space qualified and shipped from NRL to the satellite integrator in the Spring of 1996. The launch of HTSSE-II on the Advanced Global and Research Observation Satellite (ARGOS), which was originally set for mid-1996, is now scheduled for March 1998. A description of the HTSSE-II payload will be presented and the performance of the HTS components and their potential impact on future space communications systems will be described. C1 USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RP Nisenoff, M (reprint author), USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RI Wolf, Stuart/A-7513-2009 NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD JAN PY 1998 VL 110 IS 1 BP 131 EP 137 PG 7 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA ZD960 UT WOS:000072743000011 ER PT J AU Alman, PR McCallum, DN Fung, SC AF Alman, PR McCallum, DN Fung, SC TI Mid-Term Sealift: Hydrodynamic system improvements for the bow and stern SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The Mid-Term Sealift Research and Development Program was an ambitious attempt to investigate the potential for integrating new technologies into a commercially viable sealift design. This paper addresses the guidelines followed, the bow and stern designs developed, and their testing and evaluation. Since both bow and stern may be regarded as "hydrodynamic subsystems," they were analyzed on a system basis, that is, with regard to their overall contribution for energy savings, producibility and interaction with adjacent subsystems, such as propulsion. These studies resulted in a hullform with significantly improved hydrodynamic performance, which may be used as a parent for future U.S. designs. C1 USN, Auxiliary Amphibious & Mine Warfare Ships Hydrody, Sea Syst Command, Washington, DC 20350 USA. RP Alman, PR (reprint author), USN, Auxiliary Amphibious & Mine Warfare Ships Hydrody, Sea Syst Command, Washington, DC 20350 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD JAN PY 1998 VL 110 IS 1 BP 151 EP 170 PG 20 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA ZD960 UT WOS:000072743000013 ER PT J AU Grubb, M Skolnick, A AF Grubb, M Skolnick, A TI Advanced development and fleet needs - A real-time dilemma? Integrated product teams (IPTs) and technology windows SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The advent of integrated product teams (IPTs), which have been formulated and strengthened by recent acquisition reform initiatives, offers fresh opportunity for managers of modest-sized programs (below the ACAT level) and their headquarters' sponsors to achieve alignment with today's budgetary realities. Ideally IPTs bring together all the necessary people knowledgeably involved in various phases of product life cycle management, so that a new design or concept will receive the benefit of their accountability, experience and insight. While projections of a combat system's use are in decades, technology currently changes every 6-18 months. Can IPTs and planned technology insertion smooth this phase gap? The revolution or upheaval that occurs with technology change must also be within the capacity of the IPT to assimilate and manage successfully. This paper discusses the practical application and utility of IPTs to the delivery of emerging technology that provides practical solutions to urgent Fleet problems. The discussion assesses integration of the IPT process with a program of moderate size in the midst of a sponsor-directed transformation to solve Fleet problems in a more responsive and timely manner. The questions - can the existing universe of IPTs be used to help accomplish the goals of accelerated-development processes?, do such processes need an IPT of their own to fine tune project deliverables and program direction?, or, does the IPT approach lack significance in such applications? - are addressed to clarify the issue of IPT use in developmental programs of modest size targeting specific Fleet needs. C1 USN, Ctr Surface Warfare, Crane Div, Sustainable Hardware & Affordable Readiness Pract, Washington, DC 20350 USA. RP Grubb, M (reprint author), USN, Ctr Surface Warfare, Crane Div, Sustainable Hardware & Affordable Readiness Pract, Washington, DC 20350 USA. NR 7 TC 0 Z9 0 U1 2 U2 2 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD JAN PY 1998 VL 110 IS 1 BP 263 EP 276 PG 14 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA ZD960 UT WOS:000072743000021 ER PT S AU Lesher, S Spano, ML Mellen, NM Guan, L Dykstra, S Cohen, AH AF Lesher, S Spano, ML Mellen, NM Guan, L Dykstra, S Cohen, AH BE Kiehn, O HarrisWarrick, RM Jordan, LM Hultborn, H Kudo, N TI Evidence for unstable periodic orbits in intact swimming lampreys, isolated spinal cords, and intermediate preparations SO NEURONAL MECHANISMS FOR GENERATING LOCOMOTOR ACTIVITY SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT Conference on Neuronal Mechanisms for Generating Locomotor Activity CY MAR 20-23, 1998 CL NEW YORK, NEW YORK SP New York Acad Sci, Athena Neurosci Inc, E Paralyzed Vet Assoc, Lundbeck Fdn, NIH, NINDS, NIH, NIA, Natl Sci Fdn, Spinal Cord Res Fdn, Univ Tsukuba, Japan, Med Res Council Canada, Univ Copenhagens Gen Fdn ID TIME-SERIES; CHAOS; SYNCHRONIZATION; DETERMINISM C1 Univ Maryland, Dept Biol, College Pk, MD 20742 USA. USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. Univ Calif Los Angeles, Dept Physiol Sci, Los Angeles, CA 90024 USA. RP Lesher, S (reprint author), Univ Maryland, Dept Biol, College Pk, MD 20742 USA. RI Spano, Mark/B-6883-2011 FU PHS HHS [44809] NR 19 TC 6 Z9 6 U1 0 U2 1 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-168-5 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1998 VL 860 BP 486 EP 491 DI 10.1111/j.1749-6632.1998.tb09084.x PG 6 WC Behavioral Sciences; Multidisciplinary Sciences; Neurosciences SC Behavioral Sciences; Science & Technology - Other Topics; Neurosciences & Neurology GA BM35B UT WOS:000078450500050 PM 9928345 ER PT S AU Frohlich, C Lean, J AF Frohlich, C Lean, J BE Deubner, FL ChristensenDalsgaard, J Kurtz, D TI Total solar irradiance variations - The construction of a composite and its comparison with models SO NEW EYES TO SEE INSIDE THE SUN AND STARS: PUSHING THE LIMITS OF HELIO- AND ASTEROSEISMOLOGY WITH NEW OBSERVATIONS FROM THE GROUND AND FROM SPACE SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 185th Symposium of the International-Astronomical-Union on New Eyes to See Inside the Sun and Stars CY AUG 18-22, 1997 CL KYOTO, JAPAN SP Int Astron Union ID PHOTOMETRIC SUNSPOT INDEX; VARIABILITY; HELIOSEISMOLOGY; LUMINOSITY; VIRGO; TIME AB Measurements of the total solar irradiance (TSI) during the last 18 years from spacecraft are reviewed. Corrections are determined for the early measurements made by the HF radiometer within the ERB experiment on NIMBUS7 and the factor to refer ACRIM II to the ACRIM I irradiance scale. With these corrections a composite TSI is constructed for the period from 1978-1991. This time series is compared with a model that combines a magnetic brightness proxy with observed sunspot darkening and explains nearly 90% of the observed short and longterm variance. Possible, but still unverified degradation of the radiometers hampers conclusions about irradiance changes on decadal time scales and longer. C1 Phys Meteorol Observ Davos, World Radiat Ctr, CH-7260 Dorf, Switzerland. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Frohlich, C (reprint author), Phys Meteorol Observ Davos, World Radiat Ctr, CH-7260 Dorf, Switzerland. NR 25 TC 5 Z9 6 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0074-1809 BN 0-7923-5075-8 J9 IAU SYMP PY 1998 IS 185 BP 89 EP 102 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BM51L UT WOS:000078932400019 ER PT S AU Seidelmann, PK AF Seidelmann, PK BE McLean, BJ Golombek, DA Hayes, JJE Payne, HE TI Prospects for future astrometric missions SO NEW HORIZONS FROM MULTI-WAVELENGTH SKY SURVEYS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 179th Symposium of the International-Astronomical-Union on New Horizons from Multi-Wavelength Sky Surveys CY AUG 26-30, 1996 CL JOHNS HOPKINS UNIV, BALTIMORE, MD SP Int Astron Union HO JOHNS HOPKINS UNIV AB Hipparcos and the Hubble Space Telescope have demonstrated the astrometric capabilities in space. SIM and GAIA are being studied for future missions. There have been many proposals for new astrometry missions from many different countries, but most of them have not been funded. The best possibility for a mission within the next five years would be through a collaborative effort for a small, fast, cheap spacecraft which could be a precursor for future, larger, more accurate missions, which are under study. C1 USN Observ, Washington, DC 20390 USA. RP Seidelmann, PK (reprint author), USN Observ, Washington, DC 20390 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0074-1809 BN 0-7923-4802-8 J9 IAU SYMP PY 1998 IS 179 BP 79 EP 85 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BK53M UT WOS:000072466600009 ER PT S AU Kassim, NE Briggs, DS Foster, RS AF Kassim, NE Briggs, DS Foster, RS BE McLean, BJ Golombek, DA Hayes, JJE Payne, HE TI Wide-field low-frequency imaging with the VLA SO NEW HORIZONS FROM MULTI-WAVELENGTH SKY SURVEYS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 179th Symposium of the International-Astronomical-Union on New Horizons from Multi-Wavelength Sky Surveys CY AUG 26-30, 1996 CL JOHNS HOPKINS UNIV, BALTIMORE, MARYLAND SP Int Astron Union HO JOHNS HOPKINS UNIV C1 USN, Res Lab, Washington, DC 20375 USA. RP Kassim, NE (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0074-1809 BN 0-7923-4802-8 J9 IAU SYMP PY 1998 IS 179 BP 89 EP 90 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BK53M UT WOS:000072466600010 ER PT S AU Zacharias, N AF Zacharias, N BE McLean, BJ Golombek, DA Hayes, JJE Payne, HE TI Progress in wide field CCD astrometry SO NEW HORIZONS FROM MULTI-WAVELENGTH SKY SURVEYS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 179th Symposium of the International-Astronomical-Union on New Horizons from Multi-Wavelength Sky Surveys CY AUG 26-30, 1996 CL JOHNS HOPKINS UNIV, BALTIMORE, MARYLAND SP Int Astron Union HO JOHNS HOPKINS UNIV C1 USN Observ, USRA, Washington, DC 20392 USA. RP Zacharias, N (reprint author), USN Observ, USRA, Washington, DC 20392 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0074-1809 BN 0-7923-4802-8 J9 IAU SYMP PY 1998 IS 179 BP 386 EP 388 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BK53M UT WOS:000072466600097 ER PT S AU Canzian, B AF Canzian, B BE McLean, BJ Golombek, DA Hayes, JJE Payne, HE TI The 488,006,860 sources in the ISMP-A1.0 catalog SO NEW HORIZONS FROM MULTI-WAVELENGTH SKY SURVEYS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 179th Symposium of the International-Astronomical-Union on New Horizons from Multi-Wavelength Sky Surveys CY AUG 26-30, 1996 CL JOHNS HOPKINS UNIV, BALTIMORE, MARYLAND SP Int Astron Union HO JOHNS HOPKINS UNIV AB The USNO-A1.0 catalog was generated from the U.S. Naval Observatory's digitization of the Palomar Observatory Sky Survey I O and E survey plates for fields with central declination delta greater than or equal to -30 degrees, and from the European Southern Observatory R and Science Research Council J survey plates for fields with central delta less than or equal to -35 degrees using the Precision Measuring Machine (PMM) located at the Flagstaff Station. It lists positions (alpha and delta in J2000) and brightnesses (red and blue magnitudes on the parent plate system) for all objects. A flag indicates if the entry also exists in GSC1.1. C1 USN Observ, USRA, Flagstaff, AZ USA. RP Canzian, B (reprint author), USN Observ, USRA, Flagstaff, AZ USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0074-1809 BN 0-7923-4802-8 J9 IAU SYMP PY 1998 IS 179 BP 422 EP 423 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BK53M UT WOS:000072466600106 ER PT B AU Moses, D Korendyke, CM Moulton, N Newmark, J AF Moses, D Korendyke, CM Moulton, N Newmark, J BE Webb, D Rust, D Schmieder, B TI The plasma environment of prominences - SOHO observations SO NEW PERSPECTIVES ON SOLAR PROMINENCES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 167 on New Perspectives on Solar Prominences CY APR 28-MAY 03, 1997 CL CTR PAUL LANGEVIN, AUSSOIS, FRANCE SP Intl Astron Union, Sci Comm Solar Terr Phys, European Off Aerosp Res & Dev, CNRS, Observ Paris, CEA, Ctr Natl Etud Spat HO CTR PAUL LANGEVIN AB We describe the observational capabilities of the SOHO EIT and LASCO instruments for prominence research. A detailed comparison of EIT He II lambda 304 and BBSO H alpha images of a quiescent prominence reveals differences in fine scale structure which are attributed to differences in radiation emission and transport mechanisms. Absorption features present in coronal EIT images are attributed to dense prominence features located between the source of the coronal emission and the observer. These features provide the locations of prominence material in coronal image sequences. Observations of a prominence eruption in both EIT HeII and LASCO C1 Fe XIV images show the heating of chromospheric material to coronal temperatures during the prominence eruption. In the last phase of the prominence eruption, a coronal mass ejection (CME) is initiated as a dark cavity forms over the prominence material and a bright loop-like structure forms over the dark cavity. C1 USN, Res Lab, Washington, DC 20375 USA. RP Moses, D (reprint author), USN, Res Lab, Code 7660-1, Washington, DC 20375 USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-70-8 J9 ASTR SOC P PY 1998 VL 150 BP 45 EP 54 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL75E UT WOS:000076565100007 ER PT B AU Hawkins, JD Helveston, MJ AF Hawkins, JD Helveston, MJ GP AMER METEOROL SOC AMER METEOROL SOC TI ERS-NSCAT capabilities/limitations in mapping tropical cyclone wind fields SO NINTH CONFERENCE ON INTERACTION OF THE SEA AND ATMOSPHERE LA English DT Proceedings Paper CT 9th Conference on Interaction of the Sea and Atmosphere at the 78th American-Meteorogical-Society Annual Meeting CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Res Lab, Monterey, CA 93943 USA. RP Hawkins, JD (reprint author), USN, Res Lab, 7 Grace Hopper Ave, Monterey, CA 93943 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 45 EP 49 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BL80E UT WOS:000076779300012 ER PT B AU Chu, PC Chen, YC Lu, SH AF Chu, PC Chen, YC Lu, SH GP AMER METEOROL SOC AMER METEOROL SOC TI Evaluation of ice-albedo feedback by a coupled atmosphere-ocean model SO NINTH CONFERENCE ON INTERACTION OF THE SEA AND ATMOSPHERE LA English DT Proceedings Paper CT 9th Conference on Interaction of the Sea and Atmosphere at the 78th American-Meteorogical-Society Annual Meeting CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Chu, PC (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 142 EP 145 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BL80E UT WOS:000076779300037 ER PT B AU Smith, DR Saltzman, J Vieira, MEC Whitford, DJ Wright, WA Robichaud, RM Geer, IW McManus, DE Murphree, JT AF Smith, DR Saltzman, J Vieira, MEC Whitford, DJ Wright, WA Robichaud, RM Geer, IW McManus, DE Murphree, JT GP AMER METEOROL SOC AMER METEOROL SOC TI The Maury Project: A look to the future SO NINTH CONFERENCE ON INTERACTION OF THE SEA AND ATMOSPHERE LA English DT Proceedings Paper CT 9th Conference on Interaction of the Sea and Atmosphere at the 78th American-Meteorogical-Society Annual Meeting CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. RP Smith, DR (reprint author), USN Acad, Dept Oceanog, 572 Holloway Rd, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP J5 EP J8 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BL80E UT WOS:000076779300061 ER PT B AU Duzenli, O Fargues, MP AF Duzenli, O Fargues, MP BE Li, F TI Wavelet-based feature extractions method for classification applications SO NINTH IEEE SIGNAL PROCESSING WORKSHOP ON STATISTICAL SIGNAL AND ARRAY PROCESSING, PROCEEDINGS LA English DT Proceedings Paper CT 9th IEEE Signal Processing Workshop on Statistical Signal and Array Processing (SSAP98) CY SEP 14-16, 1998 CL PORTLAND, OR SP IEEE DE wavelets; classification; dimension reduction AB This work discusses feature extraction and dimension reduction issues in the context of classification applications. A new type of projection pursuit algorithm is presented. This scheme is designed to reduce the number of class features obtained from the wavelet packet decomposition of the signals to be classified. Results show the simple scheme can be used to classify various types of signals in noisy environment. C1 USN, Postgrad Sch, ECE Dept, Monterey, CA 93943 USA. RP Duzenli, O (reprint author), USN, Postgrad Sch, ECE Dept, Code EC-Fa, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5010-3 PY 1998 BP 176 EP 179 DI 10.1109/SSAP.1998.739363 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BM16N UT WOS:000077871800045 ER PT B AU Schneidewind, N Laprie, JC Nikora, A Lyu, M Musa, J Everett, B AF Schneidewind, N Laprie, JC Nikora, A Lyu, M Musa, J Everett, B GP IEEE IEEE TI Issues in the next generation of dependability standards SO NINTH INTERNATIONAL SYMPOSIUM ON SOFTWARE RELIABILITY ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 9th International Symposium on Software Reliability Engineering (ISSRE 98) CY NOV 04-07, 1998 CL PADERBORN, GERMANY SP IEEE Comp Soc Tech Council Software Engn, IEEE Reliabil Soc, DVE, Siemens Nixdorf, IBM, Daimler Benz, Nortel Network, DGQ, DFG, Univ Gesamthochschule Paderborn AB Existing IEEE software reliability standards do not address the characteristics of distributed systems, including client-server systems. Furthermore, these standards were issued before the widespread application of COTS and safety-critical systems. In addition, these standards do not take into account the influence on reliability of such process improvement measures as inspections, reuse, and object-oriented design paradigms. Lastly: these standards do not consider both hardware and software reliability nor do they include availability and maintainability. To be of value, the next generation of dependability standards must address these deficiencies. I Vith the active participation of the audience, the panel will identify and debate the future direction of dependability standards. Panel participants are the following. C1 USN, Postgrad Sch, Washington, DC 20350 USA. RP Schneidewind, N (reprint author), USN, Postgrad Sch, Washington, DC 20350 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-8186-8991-9 PY 1998 BP 101 EP 104 PG 4 WC Computer Science, Software Engineering SC Computer Science GA BM31F UT WOS:000078348800012 ER PT B AU Chu, PC Lu, SH Chen, YC AF Chu, PC Lu, SH Chen, YC GP AMER METEOROL SOC AMER METEOROL SOC TI Second kind predictability in climate models SO NINTH SYMPOSIUM ON GLOBAL CHANGE STUDIES LA English DT Proceedings Paper CT 9th Symposium on Global Change Studies/Namias Symposium on Status and Prospects for Climate Prediction at the 78th American-Meteorological-Society CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Chu, PC (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 86 EP 90 PG 3 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BL80D UT WOS:000076779200025 ER PT B AU Lean, J Rind, D AF Lean, J Rind, D GP AMER METEOROL SOC AMER METEOROL SOC TI Attribution of solar-induced climate change since 1600 SO NINTH SYMPOSIUM ON GLOBAL CHANGE STUDIES LA English DT Proceedings Paper CT 9th Symposium on Global Change Studies/Namias Symposium on Status and Prospects for Climate Prediction at the 78th American-Meteorological-Society CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Lean, J (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7673L, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 233 EP 234 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BL80D UT WOS:000076779200067 ER PT B AU Chu, PC Lu, SH Chen, YC AF Chu, PC Lu, SH Chen, YC GP AMER METEOROL SOC AMER METEOROL SOC TI Effects of Drake Passage on global climate change SO NINTH SYMPOSIUM ON GLOBAL CHANGE STUDIES LA English DT Proceedings Paper CT 9th Symposium on Global Change Studies/Namias Symposium on Status and Prospects for Climate Prediction at the 78th American-Meteorological-Society CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Chu, PC (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 261 EP 265 PG 3 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BL80D UT WOS:000076779200077 ER PT S AU Koleske, DD Wickenden, AE Henry, RL Desisto, WJ Gorman, RJ AF Koleske, DD Wickenden, AE Henry, RL Desisto, WJ Gorman, RJ BE Ponce, FA DenBaars, SP Meyer, BK Nakamura, S Strite, S TI Kinetic model for GaN growth SO NITRIDE SEMICONDUCTORS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nitride Semiconductors, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Aixtron Semiconductor Technol GmbH, Bede Sci Inc, EMCORE, Lake Shore Cryotron Inc, Morton Int, MMR Technol Inc, Nichia Chem Ind, Renishaw PLC, Rockwell Int, Siemens, SULA Technol, SVT Assoc Inc, Thomas Swan & Co Ltd, Toyoda Gosel Co Ltd, Xerox Palo Alto Res Ctr AB A kinetic model is presented to explain GaN growth. The model is based on established values for the N and Ga desorption kinetics and well founded assumptions on the adsorption and decomposition of the N and Ga containing precursors. When grown on similar nucleation layers, it is shown that high quality GaN films are achieved when the V/III ratio is chosen to be slightly larger than the Ga and N desorption rates. The model is verified by comparing the structural, optical, and electrical properties of the GaN to the growth temperature and V/III ratio. The model explains several features of GaN growth including, growth conditions for smooth surface morphology, growth conditions for highly resistive GaN, and a possible explanation for the origin of Ga and N vacancies in GaN. Based on the growth model, ordering of the GaN during growth is achieved via an adsorption/desorption cycle where Ga and N containing species are exchanged between the gas phase boundary layer and the solid surface. Consequences of the model on establishing growth conditions and run-to-run reproducability are also discussed. C1 USN, Res Lab, Div Elect Sci & Technol, Lab Adv Mat Synth, Washington, DC 20375 USA. RP Koleske, DD (reprint author), USN, Res Lab, Div Elect Sci & Technol, Lab Adv Mat Synth, Code 6861, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-387-8 J9 MATER RES SOC SYMP P PY 1998 VL 482 BP 167 EP 172 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98K UT WOS:000073983100025 ER PT S AU Glaser, ER Kennedy, TA Wickenden, AE Koleske, DD Perry, WG Davis, RF AF Glaser, ER Kennedy, TA Wickenden, AE Koleske, DD Perry, WG Davis, RF BE Ponce, FA DenBaars, SP Meyer, BK Nakamura, S Strite, S TI Location of residual donors in GaN epitaxial layers SO NITRIDE SEMICONDUCTORS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nitride Semiconductors, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Aixtron Semiconductor Technol GmbH, Bede Sci Inc, EMCORE, Lake Shore Cryotron Inc, Morton Int, MMR Technol Inc, Nichia Chem Ind, Renishaw PLC, Rockwell Int, Siemens, SULA Technol, SVT Assoc Inc, Thomas Swan & Co Ltd, Toyoda Gosel Co Ltd, Xerox Palo Alto Res Ctr AB Optically-detected electron-nuclear double resonance (ODENDOR) studies at 24 GHz on high-resistivity GaN films grown on Al2O3 have been combined with x-ray diffraction measurements to obtain information on the location of the residual shallow donors. Strong ODENDOR assigned to Ga-69,Ga-71 lattice nuclei was detected on the g=1.951 effective-mass donor resonance found on the 2.2 eV emission bands. The x-ray studies reveal that the layers are under biaxial compression with high values of strain (similar to 2-3 x 10(-3)). The quadrupole splittings for Ga-69 are smaller than those reported for strain-free samples by 15-25%. The dominant sources of the local electric field gradient (EFG) responsible for the splittings are attributed to the wurtzite crystal structure and the strain fields that arise from the lattice constant mismatch and the difference in thermal expansion coefficients. An EFG/strain relationship of 3 x 10(22) Vm(-2) per unit strain at the Ga-69,Ga-71 nuclei is deduced. The ODENDOR can be described with asymmetry parameter eta=0. This provides evidence that the donors are in the crystallites rather than near grain boundaries. C1 USN, Res Lab, Washington, DC 20375 USA. RP Glaser, ER (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-387-8 J9 MATER RES SOC SYMP P PY 1998 VL 482 BP 561 EP 566 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98K UT WOS:000073983100084 ER PT S AU Zolper, JC Han, J Van Deusen, SB Crawford, MH Biefeld, RM Jun, J Suski, T Baranowski, JM Pearton, SJ AF Zolper, JC Han, J Van Deusen, SB Crawford, MH Biefeld, RM Jun, J Suski, T Baranowski, JM Pearton, SJ BE Ponce, FA DenBaars, SP Meyer, BK Nakamura, S Strite, S TI Recent progress in implantation and annealing of GaN and AlGaN SO NITRIDE SEMICONDUCTORS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nitride Semiconductors, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Aixtron Semiconductor Technol GmbH, Bede Sci Inc, EMCORE, Lake Shore Cryotron Inc, Morton Int, MMR Technol Inc, Nichia Chem Ind, Renishaw PLC, Rockwell Int, Siemens, SULA Technol, SVT Assoc Inc, Thomas Swan & Co Ltd, Toyoda Gosel Co Ltd, Xerox Palo Alto Res Ctr AB Heterostructure modulation doped transistors (MODFETs) based on AlGaN/GaN structures have demonstrated impressive DC and microwave performance often despite high transistor access resistance. One approach to reducing the access resistance is to use selective area Si-implantation. While several reports exist on Si-implantation in GaN, little work has been done on implantation in AlGaN. In addition, more information on the annealing of implantation damage in GaN is needed to optimize its use in FETs and thyristors. We report the electrical and structural properties of Si-implanted Al0.15Ga0.85N based on Hall measurements and Rutherford Backscattering (RBS) spectra, respectively. Al0.15Ga0.85N shows less damage accumulation than GaN for a room temperature Si-implant dose of 5x10(15) cm(-2) based on the minimum channeling yield (26% for AlGaN as compared to 34% for GaN), however, as with GaN, this damage is difficult to remove by thermal annealing at similar to 1100 degrees C. We also report on high pressure (up to 15 kbar) and high temperature (up to 1500 degrees C) annealing for Si-implanted GaN. At 1250 degrees C similar to 50% electrical activation is achieved which increases to similar to 90% at 1500 degrees C. The photoluminescence of these samples is also restored, or even enhanced, by the high temperature treatments. Furthermore, RES demonstrates that complete removal of the implantation induced damage is achieved for the 1500 degrees C anneal. C1 Off Naval Res, Arlington, VA 22217 USA. RP Zolper, JC (reprint author), Off Naval Res, Arlington, VA 22217 USA. NR 0 TC 9 Z9 9 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-387-8 J9 MATER RES SOC SYMP P PY 1998 VL 482 BP 979 EP 984 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98K UT WOS:000073983100147 ER PT B AU Liu, JM Wasilik, JH AF Liu, JM Wasilik, JH BE Green, RE TI Microwave dielectric properties of a slab determined by a multi-frequency free-space technique SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS VIII LA English DT Proceedings Paper CT 8th International Symposium on Nondestructive Characterization of Materials CY JUN 15-20, 1997 CL BOULDER, CO SP Amer Soc Nondestructive Testing, Fed Aviat Adm, Fed Highway Adm, NASA Langley Res Ctr, Natl Inst Stand & Technol, Natl Sci Fdn, USAF, Wright Labs, USN, Naval Surface Warfare Ctr C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. RP Liu, JM (reprint author), USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-45900-0 PY 1998 BP 297 EP 303 PG 7 WC Materials Science, Characterization & Testing SC Materials Science GA BL94P UT WOS:000077254000047 ER PT B AU Brown, LM DeLoach, JJ Zoughi, R Ranu, E AF Brown, LM DeLoach, JJ Zoughi, R Ranu, E BE Green, RE TI Preliminary evaluation of microwave techniques for inspection of thick layered composite deck joints SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS VIII LA English DT Proceedings Paper CT 8th International Symposium on Nondestructive Characterization of Materials CY JUN 15-20, 1997 CL BOULDER, CO SP Amer Soc Nondestructive Testing, Fed Aviat Adm, Fed Highway Adm, NASA Langley Res Ctr, Natl Inst Stand & Technol, Natl Sci Fdn, USAF, Wright Labs, USN, Naval Surface Warfare Ctr C1 USN, Ctr Surface Warfare, Carderock Div, Survivabil Struct & Mat Directorate, W Bethseda, MD 20817 USA. RP Brown, LM (reprint author), USN, Ctr Surface Warfare, Carderock Div, Survivabil Struct & Mat Directorate, W Bethseda, MD 20817 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-45900-0 PY 1998 BP 305 EP 310 PG 6 WC Materials Science, Characterization & Testing SC Materials Science GA BL94P UT WOS:000077254000048 ER PT B AU Liu, JM Vernon, SN AF Liu, JM Vernon, SN BE Green, RE TI Anisotropic electric conductivities in graphite fiber reinforced composites SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS VIII LA English DT Proceedings Paper CT 8th International Symposium on Nondestructive Characterization of Materials CY JUN 15-20, 1997 CL BOULDER, CO SP Amer Soc Nondestructive Testing, Fed Aviat Adm, Fed Highway Adm, NASA Langley Res Ctr, Natl Inst Stand & Technol, Natl Sci Fdn, USAF, Wright Labs, USN, Naval Surface Warfare Ctr C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. RP Liu, JM (reprint author), USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-45900-0 PY 1998 BP 353 EP 358 PG 6 WC Materials Science, Characterization & Testing SC Materials Science GA BL94P UT WOS:000077254000056 ER PT B AU Liu, JM Brizzolara, RA Rose, DN AF Liu, JM Brizzolara, RA Rose, DN BE Green, RE TI Nondestructive characterization of the thermal diffusivity of poor conductors by a low cost, flash technique SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS VIII LA English DT Proceedings Paper CT 8th International Symposium on Nondestructive Characterization of Materials CY JUN 15-20, 1997 CL BOULDER, CO SP Amer Soc Nondestructive Testing, Fed Aviat Adm, Fed Highway Adm, NASA Langley Res Ctr, Natl Inst Stand & Technol, Natl Sci Fdn, USAF, Wright Labs, USN, Naval Surface Warfare Ctr C1 Naval Surface Warfare Ctr, Carderock Div, W Bethesda, MD 20817 USA. RP Liu, JM (reprint author), Naval Surface Warfare Ctr, Carderock Div, W Bethesda, MD 20817 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-45900-0 PY 1998 BP 739 EP 745 PG 7 WC Materials Science, Characterization & Testing SC Materials Science GA BL94P UT WOS:000077254000116 ER PT S AU Liu, JM AF Liu, JM BE Doctor, SR Lebowitz, CA Baaklini, GY TI Microwave and ultrasonic NDE of thick glass-fiber-reinforced composites SO NONDESTRUCTIVE EVALUATION OF MATERIALS AND COMPOSITES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Materials and Composites II CY MAR 31-APR 01, 1998 CL SAN ANTONIO, TX SP Soc Photo Opt Instrumentat Engineers, Fed Aviat Adm, Nondestruct Testing Informat Anal Ctr, Fed Highway Adm, Natl Inst Stand & Technol, Lawrence Livermore Natl Lab, Def Adv Res Projects Agcy, Soc Exptl Mech, Japan Soc Mech Engineers, Japanese Soc Nondestruct Inspect, USAF Res Lab, Pressure Vessel Res Council, Gas Res Inst, Amer Soc Nondestruct Testing DE thick composites; microwave; ultrasound AB Both microwave and ultrasonic techniques for NDE are based on wave propagation and scattering from discrete defects in materials. Conventional ultrasound provides good separation of reflections from material boundaries and defects by using short-pulse excitation for transducers of wide bandwidth and damping. Microwave propagation and scattering in nonmetallic composites follow similar principles as ultrasound, with the important difference that the intrinsic difference in wave impedance between material and small voids are less here than in ultrasound. As a consequence, in thick, highly inhomogeneous and somewhat porous composites, microwave NDE may be a good alternative to ultrasound which may suffers from large signal loss due to scattering from voids over a long path length. In this paper we will present microwave and ultrasound pulse-echo data in thick composites to illustrate the capabilities of microwave techniques to provide defect information generally sought after by ultrasound, viz. defect location, size, and shape. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. RP Liu, JM (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2845-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3396 BP 135 EP 146 DI 10.1117/12.301512 PG 4 WC Materials Science, Ceramics; Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BK61L UT WOS:000072738100016 ER PT B AU Nagel, DJ AF Nagel, DJ BE Rao, BK Behera, SN TI Materials for microelectromechanical systems SO NOVEL MATERIALS DESIGN AND PROPERTIES LA English DT Proceedings Paper CT International Conference on Novel Materials CY MAR 03-07, 1997 CL PURI, INDIA SP Inst Phys, Bhubaneswar, India, Virginia Commonwealth Univ, Dept Phys, Richmond, Indo US Sci & Technol Collaborat Program, USN, Naval Res Lab, Washington, DC, S N Bose Natl Ctr Basic Sci, Calcutta, India, Govt India, Dept Sci & Technol, New Delhi, India, USN, Off Naval Res AB The production of microelectromechanical systems has developed into a significant industry in the recent past. These complex systems challenge materials science and technology in ways both old and new. Initially, materials and processes from the microelectronics industry were employed to make these devices. Then, materials and associated techniques, beyond those needed for integrated circuits, were brought to bear. Now, microsystems offer many opportunities to apply new materials in order to make more capable and less expensive devices, much like the situation for larger-scale engineering systems. C1 USN, Res Lab, Washington, DC 20375 USA. RP Nagel, DJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NOVA SCIENCE PUBLISHERS, INC PI HAUPPAUGE PA 400 OSER AVE, STE 1600, HAUPPAUGE, NY 11788-3635 USA BN 1-56072-559-1 PY 1998 BP 263 EP 276 PG 14 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BK82T UT WOS:000073537500022 ER PT B AU Broughton, JQ Meli, CA Vashishta, P Kalia, RK AF Broughton, JQ Meli, CA Vashishta, P Kalia, RK BE Rao, BK Behera, SN TI Direct atomistic simulation of quartz crystal oscillators. Bulk properties and nanoscale devices SO NOVEL MATERIALS DESIGN AND PROPERTIES LA English DT Proceedings Paper CT International Conference on Novel Materials CY MAR 03-07, 1997 CL PURI, INDIA SP Inst Phys, Bhubaneswar, India, Virginia Commonwealth Univ, Dept Phys, Richmond, Indo US Sci & Technol Collaborat Program, USN, Naval Res Lab, Washington, DC, S N Bose Natl Ctr Basic Sci, Calcutta, India, Govt India, Dept Sci & Technol, New Delhi, India, USN, Off Naval Res AB Current experimental research aims to reduce the size of quartz crystal oscillators into the sub-micron range. Devices then comprise multimillion atoms and operating frequencies will be in the gigahertz regime. Such characteristics make direct atomic scale simulation feasible using large scale parallel computing. Here, we describe molecular Dynamics simulations on bulk and nanoscale device systems focussing on elastic constants and flexural frequencies. Here we find: (a) in order to achieve elastic constants within 1% of those of the bulk requires approx. one million atoms; precisely the experimental regime of interest; (b) differences from continuum mechanical frequency predictions are observable for 17 nanometer devices; (c) devices with 1% defects exhibit dramatic anharmonicity. Future work will involve the direct atomistic simulation of operating characteristics of a micron scale device. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Broughton, JQ (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU NOVA SCIENCE PUBLISHERS, INC PI HAUPPAUGE PA 400 OSER AVE, STE 1600, HAUPPAUGE, NY 11788-3635 USA BN 1-56072-559-1 PY 1998 BP 291 EP 318 PG 28 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BK82T UT WOS:000073537500024 ER PT B AU Mintmire, JW Jishi, RA White, CT AF Mintmire, JW Jishi, RA White, CT BE Rao, BK Behera, SN TI Electronic structure of conducting carbon nanotubes SO NOVEL MATERIALS DESIGN AND PROPERTIES LA English DT Proceedings Paper CT International Conference on Novel Materials CY MAR 03-07, 1997 CL PURI, INDIA SP Inst Phys, Bhubaneswar, India, Virginia Commonwealth Univ, Dept Phys, Richmond, Indo US Sci & Technol Collaborat Program, USN, Naval Res Lab, Washington, DC, S N Bose Natl Ctr Basic Sci, Calcutta, India, Govt India, Dept Sci & Technol, New Delhi, India, USN, Off Naval Res AB Recent developments using synthetic methods typical of fullerene production have been used to generate graphitic nanotubes with diameters on the order of fullerene diameters: "carbon nanotubes". Recent work by Thess, et al.suggests that [10,10] carbon nanotubes with diameters of 1.38 nm have been observed with high conductivities. This structure belongs to the same serpentine ([n,n]) family of nanotubes as the [5,5] carbon nanotube theoretically shown to have electronic states appropriate for high conductivity in our earlier work. We have calculated the electronic structure for this high-symmetry [10,10] carbon nanotube using a first-principles, self-consistent, all-electron Gaussian-orbital based local-density functional approach to calculate the band structure. We find that the electronic structure results are similar in band width and behavior near the Fermi level to our earlier results for the [5,5] nanotube. C1 USN, Res Lab, Theoret Chem Sect, Washington, DC 20375 USA. RP Mintmire, JW (reprint author), USN, Res Lab, Theoret Chem Sect, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU NOVA SCIENCE PUBLISHERS, INC PI HAUPPAUGE PA 400 OSER AVE, STE 1600, HAUPPAUGE, NY 11788-3635 USA BN 1-56072-559-1 PY 1998 BP 319 EP 327 PG 9 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BK82T UT WOS:000073537500025 ER PT B AU Papaconstantopoulos, DA Mehl, MJ Akdim, B AF Papaconstantopoulos, DA Mehl, MJ Akdim, B BE Rao, BK Behera, SN TI Applications of a new tight-binding total energy method SO NOVEL MATERIALS DESIGN AND PROPERTIES LA English DT Proceedings Paper CT International Conference on Novel Materials CY MAR 03-07, 1997 CL PURI, INDIA SP Inst Phys, Bhubaneswar, India, Virginia Commonwealth Univ, Dept Phys, Richmond, Indo US Sci & Technol Collaborat Program, USN, Naval Res Lab, Washington, DC, S N Bose Natl Ctr Basic Sci, Calcutta, India, Govt India, Dept Sci & Technol, New Delhi, India, USN, Off Naval Res C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Papaconstantopoulos, DA (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NOVA SCIENCE PUBLISHERS, INC PI HAUPPAUGE PA 400 OSER AVE, STE 1600, HAUPPAUGE, NY 11788-3635 USA BN 1-56072-559-1 PY 1998 BP 393 EP 403 PG 11 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BK82T UT WOS:000073537500031 ER PT B AU Rajagopal, AK AF Rajagopal, AK BE Rao, BK Behera, SN TI An approach to nonextensive, nonequilibrium systems: Old realizations and a new dream SO NOVEL MATERIALS DESIGN AND PROPERTIES LA English DT Proceedings Paper CT International Conference on Novel Materials CY MAR 03-07, 1997 CL PURI, INDIA SP Inst Phys, Bhubaneswar, India, Virginia Commonwealth Univ, Dept Phys, Richmond, Indo US Sci & Technol Collaborat Program, USN, Naval Res Lab, Washington, DC, S N Bose Natl Ctr Basic Sci, Calcutta, India, Govt India, Dept Sci & Technol, New Delhi, India, USN, Off Naval Res AB There are many novel materials being fabricated (or are being thought of) especially in,cluster or nanometric forms. In some of the already known such systems, one has observed persistence of long-time memory and fractal space-time behavior, which may be due to the range of interactions being comparable to the system size. Under these circumstances, the system may be nonextensive and in nonequilibrium situation. We outline here a theoretical approach to understand such systems based on the Lindbrad evolution of the density matrix for nonequilibrium state combined with the statistical mechanics of nonextensive system founded on Tsallis entropy. Some examples are cited as illustrations of our scheme. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rajagopal, AK (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU NOVA SCIENCE PUBLISHERS, INC PI HAUPPAUGE PA 400 OSER AVE, STE 1600, HAUPPAUGE, NY 11788-3635 USA BN 1-56072-559-1 PY 1998 BP 427 EP 434 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BK82T UT WOS:000073537500034 ER PT J AU Stumborg, MF Santiago, F Chu, TK Boulais, KA Price, JL AF Stumborg, MF Santiago, F Chu, TK Boulais, KA Price, JL TI Heavy ion backscattering spectroscopy (HIBS) analysis of gallium arsenide diffusion into barium fluoride layers grown by molecular beam epitaxy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE barium fluoride; gallium arsenide; heavy ion backscattering spectroscopy; diffusion ID RUTHERFORD BACKSCATTERING; GAAS AB Heavy Ion Backscattering Spectroscopy (HIBS) using 12 MeV C-12 ions was used to examine GaAs (1 0 0) and GaAs (1 1 1) layers grown by Molecular Beam Epitaxy (MBE) on BaF2 (1 0 0) and BaF2 (1 1 1) layers, respectively. HIBS was the only available technique able to verify the Ga/As ratio in these samples because X-ray Photoelectron Spectroscopy (XPS) is too surface sensitive for this task and the lighter ions used in Rutherford Backscattering Spectroscopy (RES) cannot resolve the Ga and As signals. A modified RES analysis program was used to analyze the HIBS spectra. Using the stopping power data of Ziegler et al., the HIBS analysis overestimated the thickness of a BaF2 layer by about 14% when compared to RES analysis of the same layer. HIBS was able to resolve the Ga and As peaks, as well as the two isotopes of Ga, This enhanced mass resolution made the determination of the GaAs layer stoichiometry possible, and introduced spectral features that aided in fitting HIBS simulation spectra to the data points. HIBS analysis of GaAs/BaF2/Si heteroepitaxies also showed diffusion of Ga and As into BaF2. This diffusion is temperature dependent and therefore subject to control. The information gathered from the HIBS analysis was used to confirm information obtained by in situ MBE diagnostic techniques, and in the case of the diffusion studies, provided information that was not available by those surface sensitive techniques. (C) 1998 Elsevier Science B.V. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. RP Stumborg, MF (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Code B20,17320 Dahlgren Rd, Dahlgren, VA 22448 USA. NR 16 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1998 VL 134 IS 1 BP 77 EP 86 DI 10.1016/S0168-583X(98)80036-0 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA YR238 UT WOS:000071474800010 ER PT J AU Marquez, VE Ezzitouni, A Russ, P Siddiqui, MA Ford, H Feldman, RJ Mitsuya, H George, C Barchi, JJ AF Marquez, VE Ezzitouni, A Russ, P Siddiqui, MA Ford, H Feldman, RJ Mitsuya, H George, C Barchi, JJ TI Lessons from the pseudorotational cycle: Conformationally rigid AZT carbocyclic nucleosides and their interaction with reverse transcriptase SO NUCLEOSIDES & NUCLEOTIDES LA English DT Article; Proceedings Paper CT International Conference on Nucleic Acids and Related Macromolecules: Synthesis, Structure, and Application CY SEP 04-09, 1997 CL ULM, GERMANY ID THYMIDINE; OLIGONUCLEOTIDES AB Two conformationally locked carba-AZT nucleoside 5'-triphosphates built on a rigid bicyclo[3.1.0]hexane template showed exclusive Northern (E-2) and Southern (E-3) conformations, respectively. Inhibition of reverse transcriptase (RT) occurred selectively with the Northern carba-AZT triphosphate. C1 NCI, Med Chem Lab, Div Basic Sci, NIH, Bethesda, MD 20892 USA. NCI, Expt Retrovirol Sect, Med Branch, Div Clin Sci,NIH, Bethesda, MD 20892 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Marquez, VE (reprint author), NCI, Med Chem Lab, Div Basic Sci, NIH, Bethesda, MD 20892 USA. RI Barchi Jr., Joseph/N-3784-2014 NR 11 TC 13 Z9 13 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0732-8311 J9 NUCLEOS NUCLEOT JI Nucleosides Nucleotides PY 1998 VL 17 IS 9-11 BP 1881 EP 1884 DI 10.1080/07328319808004726 PG 4 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 130VF UT WOS:000076540500046 ER PT J AU Janikowski, DL Rockefeller, CA AF Janikowski, DL Rockefeller, CA TI Awake and talking: Ambulatory surgery and conscious sedation SO NURSING ECONOMICS LA English DT Editorial Material C1 USN, Natl Naval Med Ctr, Nurse Corps, Bethesda, MD 20814 USA. RP Janikowski, DL (reprint author), USN, Natl Naval Med Ctr, Nurse Corps, Bethesda, MD 20814 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU JANNETTI PUBLICATIONS, INC PI PITMAN PA EAST HOLLY AVENUE, BOX 56, PITMAN, NJ 08071-0056 USA SN 0746-1739 J9 NURS ECON JI Nurs. Econ. PD JAN-FEB PY 1998 VL 16 IS 1 BP 37 EP 43 PG 7 WC Nursing SC Nursing GA YW408 UT WOS:000071932300008 PM 9544019 ER PT J AU Chaffee, M AF Chaffee, M TI Changes proposed for RN licenses SO NURSING ECONOMICS LA English DT Editorial Material C1 USN, Nurse Corps, Washington, DC 20350 USA. Univ Maryland, Baltimore, MD 21201 USA. RP Chaffee, M (reprint author), USN, Nurse Corps, Washington, DC 20350 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU JANNETTI PUBLICATIONS, INC PI PITMAN PA EAST HOLLY AVENUE, BOX 56, PITMAN, NJ 08071-0056 USA SN 0746-1739 J9 NURS ECON JI Nurs. Econ. PD JAN-FEB PY 1998 VL 16 IS 1 BP 45 EP 47 PG 3 WC Nursing SC Nursing GA YW408 UT WOS:000071932300010 ER PT B AU Meyer, RJ AF Meyer, RJ BE Wallace, JW Steinman, J Davani, D Elizandro, D TI Standard Object Interface Linkage (SOIL): Reuse and interoperability for everyone? SO OBJECT-ORIENTED SIMULATION CONFERENCE (OOS'98) AND THE INTERNATIONAL CONFERENCE ON SIMULATION AND MULTIMEDIA IN ENGINEERING EDUCATION (ICSEE'98), PROCEEDINGS OF LA English DT Proceedings Paper CT Object-Oriented Simulation Conference/International Conference on Simulation and Multimedia in Engineering Education at the 1998 Western MultiConference CY JAN 11-14, 1998 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE interoperability; reuse; interface; object; model AB sThe Modeling & Simulation (M&S) arena could be described as an "architecture-rich" environment - a plethora of architecture solutions have been "found" to the problem of M&S duplication (DIS, HLA, ALSP, JSIMS,JWARS, JMASS, SAMSON. et al), all promising some form of software reuse and/or interoperability. This paper proposes creating a (set of) Standard Object Interface Linkage(s) or SOIL(s) - basically an agreed-upon connection that models (objects) would use with simulations (architectures) for true "plug and play" capability. This paper suggests that it is both feasible and preferable to define such a (set of) SOIL(s), which in the limit would allow, with reasonably little simulation (architecture) modification the use of the same model (object) - literally, the same compiled code - in virtually all existing or planned simulations (architectures), something not even remotely possible today. This paper concludes that simulations (architectures) should be developed to the extent that they address different problem domains, but suggests restricting the models (objects) to development by object domain-expert consortia, using a (set of) SOIL(s), but otherwise free to choose whatever language/scheme makes sense far that domain. C1 USN, Air Warfare Ctr, Weap Div, China Lake, CA 93555 USA. RP Meyer, RJ (reprint author), USN, Air Warfare Ctr, Weap Div, Code 418200D, China Lake, CA 93555 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-142-7 PY 1998 BP 88 EP 92 PG 5 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BN55E UT WOS:000082192200011 ER PT S AU Kassab, LL Voas, J AF Kassab, LL Voas, J BE Demeyer, S Bosch, J TI Agent trustworthiness SO OBJECT-ORIENTED TECHNOLOGY: ECOOP'98 WORKSHOP READER SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT ECOOP 98 Workshop on Object-Oriented Technology CY JUL 20-24, 1998 CL BRUSSELS, BELGIUM C1 USN, Res Lab, Washington, DC 20375 USA. RP Kassab, LL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65460-7 J9 LECT NOTES COMPUT SC PY 1998 VL 1543 BP 300 EP 300 PG 1 WC Computer Science, Theory & Methods SC Computer Science GA BN79M UT WOS:000082950200110 ER PT B AU Siquig, RA Matiyevsky, A AF Siquig, RA Matiyevsky, A GP MTS MTS TI The Master Environmental Library (MEL) project SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc DE Master Environmental Library; MEL; synthetic natural environment; weather; scenario; just-in-time production AB The Master Environmental Library (MEL) (http://mel.dmso.mil) is an Internet based data discovery and ordering system providing access via a consistent single interface to oceanographic, terrain atmospheric, and near space databases and related fools residing in geographically distributed independent resource sites. The key features of MEL are a consistent metadata contents standard for the data, a consistent user-friendly interface, a generic order/delivery system, and use of standard transfer formats. Existing data centers can become MEL resource sites without changing their current data management methods or architecture, and they retain complete control over release of data. A classified parallel version of MEL has been developed for access to classified data. C1 USN, Res Lab, Monterey, CA 93943 USA. RP Siquig, RA (reprint author), USN, Res Lab, Code 7543,7 Grace Hopper Ave,MS 2, Monterey, CA 93943 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 193 EP 197 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300039 ER PT B AU Smith, DR Geer, IW McManus, DE AF Smith, DR Geer, IW McManus, DE GP MTS MTS TI The Maury Project: A program on the physical foundations for precollege teachers SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Maury Project is a joint venture of the American Meteorological Society (AMS) and the United States Naval Academy, with funding from the National Science Foundation. This unique pre-college teacher enhancement program focuses on the physical foundations of oceanography. Since its initiation in 1994 both the Navy (Naval Meteorology and Oceanography Command and the Office of Naval Research) and NOAA (National Environmental Satellite, Data and Information Service and the National Ocean Service) have become sponsors of this unique educational partnership. The primary activity of the Maury Project is the annual two-week summer workshop for teachers on various aspects of the physical foundations of oceanography. The participant teachers become peer trainers, conducting workshops for their colleagues, normally at statewide science teachers conferences, using teacher's guides on the physical aspects of oceanography as the subject matter area of the workshops. These workshops have reached thousands of teachers at workshops nationwide over the past five years. This presentation will focus on the activities of the Maury Project over the past five years. in addition, there will be an examination of the accomplishments of the program and its impact on precollege teachers, who have participated in the summer workshops as well as the peertraining sessions conducted across the country and beyond. Finally, there will be a glimpse toward the future to see the directions where the Maury Project will be headed in its efforts to promote the study of the oceans in the precollege classroom. C1 USN Acad, Annapolis, MD 21402 USA. RP Smith, DR (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 318 EP 322 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300063 ER PT B AU Clough, MO AF Clough, MO GP MTS MTS TI Shallow-water multibeam sonar meeting the littoral survey requirement of the Naval Oceanographic Office SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Naval Oceanographic Office (NAVOCEANO) conducts military hydrographic and littoral surveys which provide environmental products to the U.S. Navy and the National Imagery and Mapping Agency. Our new class of survey ships and hydrographic launches are transitioning from deep-water multibeam sonar systems and single-beam echo sounders to shallow-water multibeam systems. The exceptional efficiency achieved with multibeam systems for deep-water surveys dictates the transition to a multibeam system for shallow-water areas as well. This paper addresses the littoral survey requirements and the capabilities of these shallow-water multibeam systems to meet these requirements. The paper also considers striving for greater survey efficiency while still achieving the new IHO standards for sufficient accuracy to be safely used by mariners, both military and commercial. This paper concludes that shallow-water multibeam sonar can meet our requirements more efficiently and with greater accuracy than single-beam echo sounders. C1 USN, Oceanog Off, Stennis Space Ctr, MS 39522 USA. RP Clough, MO (reprint author), USN, Oceanog Off, 1002 Balch Blvd, Stennis Space Ctr, MS 39522 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 337 EP 341 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300066 ER PT B AU Harris, M Bourgeois, B AF Harris, M Bourgeois, B GP MTS MTS TI Improved survey accuracy with ORCA SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The advent of multibeam bathymetry systems, which are capable of total seafloor ensonification, have made fundamental changes in hydrography. The new IHO S-44 standards challenge hydrographers to achieve even greater depth and position accuracy with multibeam systems. ORCA has made incremental improvements in each of these areas as demonstrated in a series of at sea survey tests. Improvements have been made to the system that allow collection of data during turns, an order of magnitude improvement in heading measurement, and accurate measurement of vessel depth with respect to mean sea-level. Data collection during turns was achieved using a sensor that integrates inertial and GPS signals. Heading accuracy has been improved by going from a gyro based measurement system to a dual-antenna GPS phase differencing system. In addition to more accurate placement of soundings, especially in the outer beams, the system components are smaller and require less power than those replaced. Vessel depth measurements are made with a high-frequency altimeter, which also yields sea surface information including wave height, period, number and direction. An autonomous surveying capability has been developed to achieve the desired ensonification of the seafloor without over or under surveying an area. Coverage is based on the quality of data in the outer beams and the desired overlap in coverage. This paper describes the sensor and software changes made to the ORCA, and provides comparative results from system testing. C1 USN, Res Lab, Stennis Space Ctr, MS USA. RP Harris, M (reprint author), USN, Res Lab, Stennis Space Ctr, MS USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 342 EP 345 PG 4 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300067 ER PT B AU Landrum, J Mejia, P AF Landrum, J Mejia, P GP MTS MTS TI A map server for realtime hydrographic data collection systems SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc C1 USN, Res Lab, Washington, DC 20375 USA. RP Landrum, J (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 346 EP 349 PG 4 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300068 ER PT B AU Klein, F Walstad, L Aikman, F Breaker, L AF Klein, F Walstad, L Aikman, F Breaker, L GP MTS MTS TI Coastal Marine Demonstration (CMD) of forecast information to mariners of the US East Coast SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc ID MODEL C1 USN, NOAA, Off Naval Deputy, Washington, DC USA. RP Breaker, L (reprint author), USN, NOAA, Off Naval Deputy, Washington, DC USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 410 EP 413 PG 4 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300080 ER PT B AU Walter, DJ Lambert, DN Young, DC AF Walter, DJ Lambert, DN Young, DC GP MTS MTS TI Sediment characterization and mapping using high frequency acoustic and core data in the Chesapeake Bay SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB Several locations in the Chesapeake Bay were surveyed with an acoustic seafloor classification system to characterize and delineate areal distribution of surficial sediment properties.. Predictions of acoustic impedance using this system provide a capability for initial assessment and prediction of sediment properties during the survey. Color-coded trackline maps created in red-time on a computer monitor represent estimated surficial sediment facies type and location. Analyses of the color-coded maps reveal a diversity of sediment types and distribution at each site and between sites. Thick sediment coverings are predominantly fine grained as identified by low intensity acoustic returns. Thin coverings consist of more dense, granular materials and are identified by higher intensity acoustic returns. Two locations south of the mouth of the Patuxent River and one near the mouth of the Choptank River consist primarily of fine and medium silts to silty clays. These sites exhibit the lowest impedance levels on the trackline maps. Samples collected at one site slightly inside, and three sites north, of the mouth of the Patuxent River are composed of more dense, granular sands. Higher predicted impedances on the maps are indicative of dense sediments. Acoustically derived impedance predictions have been gridded and contoured to create a color-coded sediment facies province map at one of the sites. This province map provides a representation of relative sediment type and distribution at this site. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Walter, DJ (reprint author), USN, Res Lab, Code 7431, Stennis Space Ctr, MS 39529 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 467 EP 472 PG 6 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300092 ER PT B AU True, D AF True, D GP MTS MTS TI Doppler penetrometer performance in shallow water with full and reduced diameter noses SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Navy's eXpendable Doppler Penetrometer (XDP) system was used along with other measurement means to investigate an area offshore of Biloxi, Mississippi. This investigation provided co-located data in sediments ranging from a silty sand to a soft silty clay. The XDP probe is 3.5 inches in diameter, and about 3 feet long when two spacers are included. (Shorter configurations are assembled by leaving out one or both spacers.) Its forward half is solid steel with a 3.5-in-diameter hemispherical nose. Also, to achieve useful penetrations into stronger soils, it can be fitted with a "nanwhal" stinger nose which is a solid steel rod 1 inch in diameter by 2 feet long, with its own hemispherical nose. The XDP has been proven very useful in expeditiously obtaining measurements of rapid undrained shear strength in water depths of 50 to 4,000 ft. However, for applications in littoral warfare, and especially in mine countermeasures, knowledge of bottom properties is needed in shallower water. Because it relies on acoustics to obtain its penetration motion history, the XDP is subject to performance degradations in water shallower than 50 feet due to environmental noise and multiple sound ray paths. This issue was examined in this shallow offshore site investigation. The XDP is normally employed with its full-diameter nose, and the narwhal nose is used for a second drop to obtain deeper penetrations when encountering stronger soils, including stiff clays and sands. If data from a nanwhal nosed XDP could be interpreted meaningfully for weaker soils, including soft clays and muds, then operations could be simplified by routinely using the nanwhal nose irrespective of bottom material type. This issue was also examined in the soft sediment areas visited in this investigation. Nine sites were visited in the test area. Dropped penetrometer tests, coring, and acoustic scanning were done at each of the visited sites, and acoustic scanning was done in transits between the sites as well as along other selected track lines. Performance in water depths of 20 to 27 feet was only fair, due to noise and multi-path problems, and in 15 to 20 feet was poorer, due to a worsening intensity of the same problems. Improvements in filtering and signal enhancement were identified to improve shallow water performance, particularly where ship noise and/or bottom-reflection multi-path reverberations are masking the signal. The XDP produced results that could be interpreted reliably when used with its full-diameter nose in soft sediments and the narwhal nose in hard sediments (sands) The narwhal nose did not work well in soft sediments because it produced such a low response that the time of initial impact could not be identified properly. C1 USN, Facil Engn Serv Ctr, Port Hueneme, CA 93041 USA. RP True, D (reprint author), USN, Facil Engn Serv Ctr, Port Hueneme, CA 93041 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 473 EP 477 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300093 ER PT B AU Kalcic, MIT Martinez, AB Lambert, DN AF Kalcic, MIT Martinez, AB Lambert, DN GP MTS MTS TI Time-frequency analysis of acoustic imagery for bottom mapping SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB Acoustic imagery generated by the Naval Research Laboratory's ASCS (Acoustic Sediment Classification System) is analyzed using time-frequency methods. The ASCS imagery is generated using normal-incidence acoustic data. Nonlinearities in the propagating medium produce multiple harmonics in the return. Different components of the bottom and sub-bottom produce different spectral signatures, based on the harmonics that can be used to classify the bottom. Although the exact acoustic properties of the media may not be known, it is possible to segment the spectrally different components. This paper presents an efficient method for performing the time-frequency analysis. The tradeoffs between time and frequency resolution are examined and exploited to produce the best overall resolution. Examples using the ASCS data demonstrate its use for classification of acoustic imagery. Buried pipes, methane gas deposits, and other features can be differentiated using this method. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Kalcic, MIT (reprint author), USN, Res Lab, Code 7441, Stennis Space Ctr, MS 39529 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 499 EP 503 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300099 ER PT B AU Warrenfeltz, L McCarren, D AF Warrenfeltz, L McCarren, D GP MTS MTS TI Naval Oceanographic Office ocean survey 2010 SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Naval Oceanographic Office (NAVOCEANO) operates eight survey ships and two aircraft around the world, collecting data in support of naval operations. As technology changes, NAVOCEANO will continue to modify its concept of doing business to keep up with the direction of the technology. This paper is the Commanding Officer's vision of the direction the data collection effort will take in the coming years. Assumptions and limiting factors, in the context of the Navy and Department of Defense vision for 2010, are reviewed. For six different technology areas, we discuss: how we do it now; how we expect to do it in the "near term"; and how we expect to do it in 2010. These areas include bathymetry systems, acoustic systems, buoys, autonomous underwater vehicles, communications, meteorology, and airborne oceanography. A theoretical scenario is presented to bring all aspects of sun ey into one consolidated picture of NAVOCEANO's data collection efforts in 2010. C1 USN, Oceanog Off, Integrat & Technol Dept, Stennis Space Ctr, MS 39522 USA. RP Warrenfeltz, L (reprint author), USN, Oceanog Off, Integrat & Technol Dept, Stennis Space Ctr, MS 39522 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 580 EP 584 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300115 ER PT B AU Whitford, DJ Smith, DR Wright, WA AF Whitford, DJ Smith, DR Wright, WA GP MTS MTS TI The physical oceanography and meteorology curriculum at the United States Naval Academy: Environmental education for naval officers in the 21st century SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The naval warfare environment extends from the bottom of the ocean to the top of the atmosphere. In order to effectively operate in such diverse arenas, naval officers require an understanding of not only waves, tides and currents, but the characteristics of the deep ocean and the littoral zone, the processes governing the atmosphere as well as the ocean, and most importantly, knowledge of how this marine environment affects modern warfare systems. The mission of the United States Naval Academy (USNA) is to prepare midshipmen for their future careers as U.S. Navy and U.S. Marine Corps officers. The Oceanography program at USNA is a unique academic major, designed to provide future officers with a thorough understanding of the ocean and the atmospheric environment in which they will be operating during their professional military careers. This undergraduate program focuses on the scientific disciplines of physical oceanography and meteorology with practical application toward naval operations. The program includes a significant number of science, mathematics and engineering courses to provide midshipmen with a strong technical background in preparation for subsequent naval technical schools and graduate school. The program includes a wide variety of upper division elective offerings which include biological, chemical, geological, and physical oceanography; meteorology; remote sensing; and as independent research opportunities. This paper focuses on how the USNA Oceanography major curriculum prepares midshipmen to operate effectively in the marine environment of the 21(st) century. C1 USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. RP Whitford, DJ (reprint author), USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. NR 2 TC 0 Z9 0 U1 0 U2 2 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 601 EP 605 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300120 ER PT B AU Beach, RA Kinder, TH Vincent, CL AF Beach, RA Kinder, TH Vincent, CL GP MTS MTS TI Long-term, in situ observations in the coastal zone SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc C1 Off Naval Res, Arlington, VA 22217 USA. RP Beach, RA (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 641 EP 645 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300128 ER PT B AU Blackmon, F Jarvis, S Morrissey, R Lambert, D AF Blackmon, F Jarvis, S Morrissey, R Lambert, D GP MTS MTS TI High-rate underwater acoustic telemetry with applications in training, test and evaluation SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Engineering, Test and Evaluation Department at the Naval Undersea Warfare Center Division, in Newport RI has developed an underwater acoustic telemetry system capable of reliable real time full duplex communication at throughput rates of 900 and 1800 bits per second. The system was originally designed for use on several shallow water training ranges which are currently being designed and installed by the Navy. However, the acoustic modems have also been successfully used to support other deep and shallow water T&E applications. In the Submarine Virtual Torpedo Project (SubVTP), the acoustic telemetry system forms the last link in a secure (encrypted), full duplex, wide area network. That network connects real submarines on range at the Atlantic Undersea Test and Evaluation Center (AUTEC), Bahamas to high fidelity torpedo simulations in Newport. The acoustic modems are required to use transducers that am organic to undersea ranges and to submarines. This places severe limitation on signal bandwidth, frequency allocation, and receiver diversity options. The problem is further complicated by the need to simultaneously acoustically track the submarines during acoustic communications. The acoustic telemetry system has also been used to download data files by providing a one way data link from underway submarines during electromagnetic measurement trials. The files were then used by trial analysts for making in-situ assessments of the data being collected. This paper will review the design of the acoustic telemetry system, and describe present and future applications of the system. It will also discuss the efforts involved in moving acoustic telemetry from the lab bench into the arena of large applications. C1 USN, Undersea Warfare Ctr, Div Newport, Newport, RI 02840 USA. RP Blackmon, F (reprint author), USN, Undersea Warfare Ctr, Div Newport, Newport, RI 02840 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 678 EP 682 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300135 ER PT B AU Al-Kurd, A Yang, TC AF Al-Kurd, A Yang, TC GP MTS MTS TI Underwater coherent acoustic communications performance during the LWAD 98-1 experiment SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB Underwater acoustic communications data using phase modulated signals were collected during the Littoral Warfare Advanced Development (LWAD) 98-1 experiment. The signals were projected from both a drifting modem and from a towed source. Data of several different baud rates were transmitted and used to evaluate the performance of the phase coherent communication algorithm. The performance of the communication algorithm is correlated with signal coherence and signal-to-noise ratio (SNR). The results of this and future analysis will be used to guide future algorithm development and system design. C1 USN, Res Lab, Washington, DC 20375 USA. RP Al-Kurd, A (reprint author), USN, Res Lab, Code 7120, Washington, DC 20375 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 691 EP 695 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300137 ER PT B AU True, D Girard, J AF True, D Girard, J GP MTS MTS TI Thin-blade plow behavior in seafloor sand SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB This paper addresses the behavior of thin-blade plows in sand, such as would be used to bury small cables, and presents a method for predicting such behavior. The method is based on model plow test data from a laboratory test bed and a field test site, viewed in a framework based on established soil mechanics relationships. It focuses on the critical confining stress of st sand as the key parameter controlling maximum plowing resistance force. In most sands (except those having extremely high permeability), the plowing resistance force at normal plowing speeds is shown to reflect undrained shearing, wherein the shearing resistance depends directly on the critical confining stress. Thus, the resistance is a function of sand grain characteristics and packing density, and is relatively constant with respect to overburden and plowing speed so long as the plowing speed remains above a critical transition value (dependent on permeability). At slower speeds, which allow partial drainage, the plowing resistance is shown to vary approximately linearly with plowing speed, decreasing to a quasistatic value (dependent mainly on overburden) when the speed is so low (relative to permeability) that drainage is virtually complete. A formula is derived for reduced plowing resistance below the critical plowing speed; although this behavior is quite interesting academically, it is the greater plowing resistance encountered as a worst case at speeds above the critical speed that is of real practical value in designing a plowing system and its supporting towing capability. Above the critical speed, the plowing resistance is shown to conform to the soil being sheared as a pseudo-plastic material. This simple worst-case prediction is readily applied to plow system design. C1 USN, Facil Engn Serv Ctr, Port Hueneme, CA 93041 USA. RP True, D (reprint author), USN, Facil Engn Serv Ctr, Port Hueneme, CA 93041 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 756 EP 762 PG 7 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300149 ER PT B AU Willis, ZS Goodson, J Danford, E AF Willis, ZS Goodson, J Danford, E GP MTS MTS TI The USN move to electronic charting SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB Accurate navigation is a fundamental need of every ship, submarine and boat in the United States Navy. The Navy is beginning to transition from maritime navigation relying primarily on paper products, to digital navigation with GPS positioning. The Navy hopes to build on the efforts of the civil shipping community and bring Electronic Chart Display and Information Systems (ECDIS) into general use. This paper will report the status of the Navy's transition to electronic charting. We will describe the DOD policies that pertain to charting data, our relationship with the National Imagery and Mapping Agency (NIMA), and the corresponding impact on electronic charting. We will discuss the establishment of the Electronic Charting Display and Information - Navy (ECDIS-N) policy and the necessary differences between the military and civil applications. Finally we will outline the changes we expect to occur in U.S. Navy operations with the advent of ECDIS-N and continuous GPS position fixes. C1 USN, Washington, DC 20350 USA. RP Willis, ZS (reprint author), USN, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 792 EP 796 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300155 ER PT B AU Benson, RA AF Benson, RA GP MTS MTS TI Office of Naval Research program in Underwater Acoustic Communications SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Office of Naval Research (ONR) is sponsoring a number of Science and;Technology (S&T) initiatives in the area of Underwater Acoustic Communications (Acomms). These initiatives are resulting in the development of new signaling schemes and signal processing algorithms. The scope of these initiatives ranges from low data rate (100-1,000 bits per second), low power, non-coherent, covert modulation techniques to high data rate (10,000 bits per second), high power, phase coherent technologies for the transmission of large amounts of digital data. ONR's Underwater Acomms program includes basic, applied and advanced development research projects. Recently, new commercial underwater acomms modulation and demodulation (modem) systems have been introduced using these new acomms technologies. They are used for transmitting voice, text and instrument data between submerged sources and remote receivers. Typical scientific acomms modem applications include real-time data transfer between bottom or surface moored ocean buoys and autonomous unmanned vehicles (AUVs). Military applications include submarine-to-surface ship, submarine-to-submarine, submarine-to-AW, and submarine-to-distributed sensor network data links. C1 Off Naval Res, Arlington, VA 22217 USA. RP Benson, RA (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 845 EP 849 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300166 ER PT B AU Coleman, JE Spinrad, RW AF Coleman, JE Spinrad, RW GP MTS MTS TI Optical variability in the northern Chesapeake Bay SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc C1 USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. RP Coleman, JE (reprint author), USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 861 EP 865 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300169 ER PT B AU Coleman, JE Malek-Madani, R Smith, DR AF Coleman, JE Malek-Madani, R Smith, DR GP MTS MTS TI Visualization of fluid flows using Mathematica SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB We present numerical solutions to two fundamental flows in fluid dynamics: a) Serrin's swirling vortex, and b) the Rayleigh-Benard flow In each case we solve a system of nonlinear ordinary differential equations that arise from the velocity field and monitor the evolution of particles of fluids. The velocity fields in turn are solutions of partial differential equations that govern the conservation of mass and the balance of linear momentum in each dow. All of the computations, whether symbolic or numerical, are performed in Mathematica. The computational code essential to visualizing each dow is presented in the sequel. C1 USN Hosp, Annapolis, MD 21412 USA. RP Coleman, JE (reprint author), USN Hosp, Annapolis, MD 21412 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 871 EP 880 PG 10 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300171 ER PT B AU Clarke, JR AF Clarke, JR GP MTS MTS TI Contrasts between semi-closed circuit underwater breathing apparatus of the '70s and the '90s SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB In the 1970s, semi-closed UBA were used for military and salvage operations by the U.S. Navy. Semi-closed UBA were replaced by fully closed units with markedly improved oxygen control in the 1980s. We are now seeing a striking increase in the use of semi-closed UBA by civilian divers in the recreational and "technical" diving market. There is also a resurgence of semi-closed UBA use by the Navy. The Navy's current interest in the UBA is for the same reasons that recreational divers are finding them appealing - they allow long diving durations, are mechanically simple, easy to maintain compared to a fully closed-circuit UBA, and are relatively inexpensive. The UBA of the '70s carried large breathing bottles and an orifice which injected a continuous gas flow of 8-22 L/min; enough flow to support a diver's metabolic oxygen consumption of up to 3 L/min. The modern UBA differ from those of the past primarily by their compactness, obtained by a reduction in the size of gas supply bottles. However, to maintain a reasonable gas duration, constant gas injection rate has also been reduced, typically from 11 L/min from the '70s UBA to about 4 L/min. The drawback to that reduced flow rate is that during heavy exercise, especially near the surface, a diver can become dangerously hypoxic, without warning. The Navy has instituted new diving procedures to minimize that risk. We have also developed a semi-closed UBA simulation as a training aid to demonstrate how such low-flow UBA can lead a diver into trouble. Even with new diving procedures and sophisticated training toots, the semiclosed UBA diver will still be exposed to more risks that an open-circuit SCUBA diver. The one safety feature that is most needed by semi-dosed UBA divers is an integrated, reliable oxygen monitor. The Navy recently had to rescind a requirement to use such devices simply because the available sensors were not reliable. All closed-circuit divers could also benefit from a CO2 monitor, one of the holy grails of the diving industry for the past 25 years. C1 USN, Expt Diving Unit, Panama City, FL 32407 USA. RP Clarke, JR (reprint author), USN, Expt Diving Unit, Panama City, FL 32407 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 978 EP 982 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300191 ER PT B AU Southerland, DG AF Southerland, DG GP MTS MTS TI A novel portable digital device for measuring temperatures of humans and equipment in the underwater environment SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Navy Experimental Diving Unit (NEDU) evaluates equipment used by divers in the underwater environment. The evaluations often require the collection of temperature data from the equipment and divers involved in the testing. Currently we use thermistors which require bulky industrial rack-mounted, signal conditioning modules that are kept topside in a data acquisition monitoring space distant to the device or diver being monitored. This system has proven to be adequate for the needs of NEDU. However, we are expanding our monitoring capabilities from the laboratory (NEDU test pool or hyperbaric chambers) to the open water. The current temperature measuring system is inadequate for field conditions and could be improved in four areas: 1) Portability - it is desirable to monitor divers in the open water, using portable battery powered sensor technology. 2) System Size - The analog signals require bulky signal conditioners to avoid degradation by the noisy environment and to convert the sensor output to conventional units. 3) Wiring Count- A significant number of available wires are necessary for studies requiring multiple temperature measurement sites; each thermistor requires three wires. 4) Cost - The thermistors and associated signal conditioners are relatively expensive. This paper discusses the preliminary evaluation of a novel commercially available digital thermometer which offers improved performance in areas mentioned. This device consists of an integrated circuit in a PR35 form, which looks like a small, elongated plastic transistor. It is about half the size of a pencil eraser and has three leads. One lead is the ground, one is the data line, and the third lead is used for power. The digital thermometer can also be used in a two wire configuration, in which the power lead is not used - the data lead provides both data communication and power. Communication to and from the digital thermometer (including temperature readings) is in digital format over the single data lead. The digital thermometer is calibrated by the manufacturer to +/- 0.5 degrees C over the range 0 degrees C - 70 degrees C, and has a total operating range of -55 degrees C to 125 degrees C. The device can be queried to give < 0.05 degrees C resolution. Multiple digital thermometers may be tied to the same lines and each digital thermometer has its own, unique 64-bit identification code. Each can be queried individually. This allows many digital thermometers to be used with only three wires. The digital thermometer appears to provide the desired improvements. It is relatively inexpensive, it allows multiple digital thermometers to be connected using only two or three wires, the digital signals require no external signal conditioning and are less susceptible to noise, and the digital thermometer is extremely portable and low-powered (5V, 1 mA). Experience at NEDU has shown that the devices typically fall outside the manufacturer's specifications, but can be recalibrated in-house to give the desired accuracy. Since the device is not hermetically sealed, it must be coated with a water resistant covering before being used in wet conditions. If simultaneous temperature conversions are required, the separate power lead should be used instead of parasitic power. Recalibration frequency has not been determined. Also, we are attempting to use this device outside the domain of the manufacturer's original intent. The opinions expressed in this paper are those of the author and not necessarily those of the Navy Experimental Diving Unit or the U.S. Navy. This paper does not constitute an endorsement for any commercial product or device. C1 USN, Expt Diving Unit, Panama City, FL 32407 USA. RP Southerland, DG (reprint author), USN, Expt Diving Unit, Panama City, FL 32407 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 987 EP 991 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300193 ER PT B AU Gallagher, D AF Gallagher, D GP MTS MTS TI Hands-Free Diver Video & Head-Up Display System SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The Coastal Systems Station (CSS), Panama City, Florida is one of the US Navy's premier organizations providing research, engineering, and operational applications of technology in the coastal environment. CSS has expertise in diving systems, amphibious warfare, underwater sensors, and naval special operations. A new program, called the Coastal Operations Program, has been initiated to promote nonmilitary applications of defense technology. It was under his program that the Hands-Free Diver Video & Head-Up Display System was produced. The system comprises a miniature color video camera, light, and "head-up" diver display. The video camera and light are built into a single underwater housing. This camera/light unit can mount to the top of a diver's full facemask, or to a diver-worn headband. The head-up display is a miniature, color LCD (liquid crystal display) built into an underwater housing that mounts to the right side of the facemask. The display unit is located in front of the diver's right eye, and can be flipped up out of the way when not needed (see Fig. 1). The camera video may be viewed simultaneously on the diver's display, so that the diver can perform underwater video work completely hands-free, using the display as a viewfinder. The system is powered from the surface via a Topside Controller Unit (TCU) through a 200-FT umbilical cable. Two video output connectors on the TCU panel allow topside monitoring and recording of the diver's camera video. An input connector and selector switch allow an alternate video signal to be sent to the diver's display from the surface. C1 USN, Coastal Syst Stn, Dahlgren Div, Ctr Surface Warfare, Panama City, FL 32407 USA. RP Gallagher, D (reprint author), USN, Coastal Syst Stn, Dahlgren Div, Ctr Surface Warfare, Panama City, FL 32407 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 992 EP 995 PG 4 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300194 ER PT B AU McDonald, VK Rice, JA Fletcher, CL AF McDonald, VK Rice, JA Fletcher, CL GP MTS MTS TI Telesonar testbed engineering and sea trials SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The US Navy is developing undersea acoustic telemetry and ranging (telesonar) technology for use in shallow water. This paper describes an autonomous, high-fidelity, testbed developed to aid data acquisition, signal design, and modem development. C1 USN, Space & Naval Warfare Syst Ctr, Acoust Branch, San Diego, CA 92152 USA. RP McDonald, VK (reprint author), USN, Space & Naval Warfare Syst Ctr, Acoust Branch, Code D881, San Diego, CA 92152 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 1001 EP 1006 PG 6 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300196 ER PT B AU Rice, JA Shockley, RC AF Rice, JA Shockley, RC GP MTS MTS TI Battery-energy estimates for telesonar modems in a notional undersea network SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB This study presents estimates of lifetime energy usage by candidate telesonar modems operating as network nodes for a nominal acoustic environment and assumed communications-link duty cycles. These energy estimates support parametric analysis, power budgeting, resource optimization, and network design for telesonar networks. A noteworthy observation is the 40-fold reduction in battery energy required by new telesonar modems compared to previous commercial modems. C1 USN, Space & Naval Warfare Syst Ctr, Acoust Branch, San Diego, CA 92152 USA. RP Rice, JA (reprint author), USN, Space & Naval Warfare Syst Ctr, Acoust Branch, Code D881, San Diego, CA 92152 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 1007 EP 1015 PG 9 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300197 ER PT B AU Baxley, PA Bucker, H Rice, JA AF Baxley, PA Bucker, H Rice, JA GP MTS MTS TI Shallow-water acoustic communications channel modeling using three-dimensional Gaussian beams SO OCEAN COMMUNITY CONFERENCE'98: CELEBRATING 1998 INTERNATIONAL YEAR OF THE OCEAN, PROCEEDINGS VOLS 1 AND 2 LA English DT Proceedings Paper CT Marine-Technology-Society Annual Conference CY NOV 16-19, 1998 CL BALTIMORE, MD SP Marine Technol Soc AB The propagation of high-frequency acoustic communication signals in shallow-water environments is adversely affected by a complex multipath structure and the inhomogeneous, nonstationary nature of the medium and its boundaries. The resulting multipath spread and Doppler spread can significantly disperse and distort the signal as it propagates through the channel. Recent progress in the development of a physics-based numerical propagation model that attempts to account for these effects is presented. The ultimate objective of this effort is to provide for the prediction of the output of the quadrature detector (QD, an analog of the discrete Fourier transform) in a time-variant, doubly-dispersive, shallow-water channel. Three-dimensional Gaussian Beam tracing is used so that out-of-plane reflections from rough surfaces or sloping bathymetry can be adequately modeled. The approach is to trace, in three-dimensions, closely spaced microbeams of a finite-duration CW pulse from source to receiver, accumulating travel-time, phase-shift, and Doppler-shift information for each microbeam. This information is used to construct the QD response for each microbeam. The total QD response is then obtained by summing the QD responses of all component microbeams. C1 USN, Space & Naval Warfare Syst Ctr, Acoust Branch, San Diego, CA 92152 USA. RP Baxley, PA (reprint author), USN, Space & Naval Warfare Syst Ctr, Acoust Branch, Code D881, San Diego, CA 92152 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-21-1 PY 1998 BP 1022 EP 1026 PG 5 WC Engineering, Marine; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Engineering; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BP21L UT WOS:000084418300199 ER PT B AU Su, MY Wesson, JC Teague, WJ Burge, RE AF Su, MY Wesson, JC Teague, WJ Burge, RE BE Zhang, J TI Breaking wave statistics in nearshore and surf zones SO OCEAN WAVE KINEMATICS, DYNAMICS AND LOADS ON STRUCTURES LA English DT Proceedings Paper CT International OTRC Symposium on Ocean Wave Kinematics, Dynamics and Loads on Structures (WAVE 98) CY APR 30-MAY 01, 1998 CL HOUSTON, TX SP Offshore Technol Res Ctr, Amer Soc Civil Engineers AB During the Sandy Duck '97 Experiment at Duck, NC (Sept-Oct. 1997) we deployed bubble measuring arrays in the nearshore region (floating, 0.9-2.3km offshore, 8-14m water depths) and in the surf zone (bottom mounted, 4m water depth). Each array had acoustic resonators, to measure bubble density for bubbles with radii from 15 mu to 1200 mu, as well as void fraction sensors and an accelerometer. Outside the surf zone breaking waves ate generated mostly by local winds. While shoaling effects, tides and swell contribute less to wave breaking outside the surf zone, they are most important within it. Bubbles generated by these waves and injected into the surface layer provide a measure of breaking intensity. The temporal and vertical response of the bubble density field to rapid changes in wind and waves, as measured by the acoustic resonator arrays, are presented here to analyze nearshore and surf zone wave breaking processes. The acoustic resonators resolve the roll-off in bubble density spectra at small radii, confirming previous optical determinations of this characteristic of the bubble density spectra. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Su, MY (reprint author), USN, Res Lab, Code 7330, Stennis Space Ctr, MS 39529 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0336-8 PY 1998 BP 297 EP 304 PG 8 WC Engineering, Marine; Engineering, Civil; Water Resources SC Engineering; Water Resources GA BN83X UT WOS:000083146200035 ER PT B AU Su, MY Teague, WJ Burge, RE Wesson, JC AF Su, MY Teague, WJ Burge, RE Wesson, JC BE Edge, BL Hemsley, JM TI Variations of breaking wave statistics across the nearshore zone SO OCEAN WAVE MEASUREMENT AND ANALYSIS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 3rd International Symposium on Ocean Wave Measurement and Analysis (WAVES 97) CY NOV 03-07, 1997 CL VIRGINIA BEACH, VA SP Coastal Zone Fdn, Amer Soc Civil Engineers, Coastal Zone Management omm, Waves & Wave Forces Comm, Rubble Mound Struct Comm AB Water depth, bathymetric features, and tidal cycle have significant effects on wave-breaking characteristics in the nearshore or surf zone. Bubbles generated by wave-breaking provide a quantitative measure of breaking intensity. Void fraction is related to wave breaking since it provides a measure of air content or bubbles. During the Sandy Duck 97 Experiment at Duck NC (September-October, 1997), three arrays were deployed at mean water depths ranging from 2 to 5 m at offshore distances of 180, 240, and 300 m. Each array consisted of 6 void fraction meters distributed over depth. The data from these arrays provide the vertical distribution of void fraction caused by wave breaking inside the surf zone. Temporal variations of void fraction profiles over several tidal cycles are presented here to analyze the nearshore wave breaking processes. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Su, MY (reprint author), USN, Res Lab, Code 7330, Stennis Space Ctr, MS 39529 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0346-5 PY 1998 BP 510 EP 523 PG 4 WC Engineering, Marine; Engineering, Civil; Mechanics; Water Resources SC Engineering; Mechanics; Water Resources GA BN85F UT WOS:000083193400038 ER PT B AU Dawson, TH AF Dawson, TH BE Edge, BL Hemsley, JM TI Statistics for wave crests in heavy seas SO OCEAN WAVE MEASUREMENT AND ANALYSIS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 3rd International Symposium on Ocean Wave Measurement and Analysis (WAVES 97) CY NOV 03-07, 1997 CL VIRGINIA BEACH, VA SP Coastal Zone Fdn, Amer Soc Civil Engineers, Coastal Zone Management omm, Waves & Wave Forces Comm, Rubble Mound Struct Comm AB Statistics for wave crests in heavy seas are described for Bretschneider and Jonswap sea states using scale measurements from laboratory simulations. Attention is directed toward the relative number of high waves expected at a fixed location and the average manner in which these waves come along. The Rayleigh probability law and Markov theory are used to provide a theoretical basis for predictions. Nonlinear effects are included using a Stokes correction. Results from computer simulations are used for comparison purposes. C1 USN Acad, Annapolis, MD 21402 USA. RP USN Acad, Annapolis, MD 21402 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0346-5 PY 1998 BP 524 EP 538 PG 3 WC Engineering, Marine; Engineering, Civil; Mechanics; Water Resources SC Engineering; Mechanics; Water Resources GA BN85F UT WOS:000083193400039 ER PT B AU Hwang, PA Walsh, EJ Krabill, WB Swift, RN AF Hwang, PA Walsh, EJ Krabill, WB Swift, RN BE Edge, BL Hemsley, JM TI Measuring winds and waves using altimeters SO OCEAN WAVE MEASUREMENT AND ANALYSIS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 3rd International Symposium on Ocean Wave Measurement and Analysis (WAVES 97) CY NOV 03-07, 1997 CL VIRGINIA BEACH, VA SP Coastal Zone Fdn, Amer Soc Civil Engineers, Coastal Zone Management omm, Waves & Wave Forces Comm, Rubble Mound Struct Comm ID SURFACE CONTOUR RADAR; GREENLAND ICE-SHEET; SPEED ALGORITHM; LASER ALTIMETRY AB Remote sensing from aircraft and satellite platforms is an efficient way of obtaining synoptic data on the ocean surface. Altimeters can produce spatial measurements of wind and wave parameters in areas ranging from global to regional scales. In this paper thr ee altimetry systems for wind and wave measurements are described. the spaceborne altimeter (ALT), the airborne scanning radar altimeter (SRA) and the aii borne topographic mapper (ATM, a scanning lidar system). Verifications of spaceborne altimeter measurements with collocated ocean buoy data show excellent agreement between the two data sets. The spatial resolution of spaceborne altimetry may not be suitable for near coastal areas, where strong bathymetric variations have profound effects on the wave propagation and the wind wave growth rate. For these areas, airborne systems offer high-resolution surface mapping. The lateral resolution of SRA is on the order of 10 m and the resolution of ATM is one order of magnitude better. These fine resolution measurements can be used to study the dynamics and the statistics of waves in the inhomogeneous coastal environment. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Hwang, PA (reprint author), USN, Res Lab, Code 7332, Stennis Space Ctr, MS 39529 USA. NR 21 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0346-5 PY 1998 BP 552 EP 562 PG 3 WC Engineering, Marine; Engineering, Civil; Mechanics; Water Resources SC Engineering; Mechanics; Water Resources GA BN85F UT WOS:000083193400041 ER PT B AU Palo, PA AF Palo, PA BE Edge, BL Hemsley, JM TI Wave analysis using new Harmonic Phase Tracking SO OCEAN WAVE MEASUREMENT AND ANALYSIS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 3rd International Symposium on Ocean Wave Measurement and Analysis (WAVES 97) CY NOV 03-07, 1997 CL VIRGINIA BEACH, VA SP Coastal Zone Fdn, Amer Soc Civil Engineers, Coastal Zone Management omm, Waves & Wave Forces Comm, Rubble Mound Struct Comm AB A uniquely-new signal processing technique called Harmonic Phase Tracking (HPT) has been developed and validated using a variety of signal types. Like Fourier Series, this technique models a signal as a summation of sinusoids; the important difference is that HPT adaptively solves for the rank and best component frequencies which are then used to find amplitudes and phases. This paper outlines the method and its new significant capabilities versus other signal processing methods, and illustrates how HPT was used to analyze the temporal and spatial characteristics of one hurricane wave field. C1 USN, Facil Engn Serv Ctr, Port Hueneme, CA 93043 USA. RP Palo, PA (reprint author), USN, Facil Engn Serv Ctr, Code ESC51,1100 23rd Ave, Port Hueneme, CA 93043 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0346-5 PY 1998 BP 975 EP 990 PG 6 WC Engineering, Marine; Engineering, Civil; Mechanics; Water Resources SC Engineering; Mechanics; Water Resources GA BN85F UT WOS:000083193400075 ER PT B AU Kriebel, DL AF Kriebel, DL BE Edge, BL Hemsley, JM TI Use of transient waves in wave barrier model testing SO OCEAN WAVE MEASUREMENT AND ANALYSIS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 3rd International Symposium on Ocean Wave Measurement and Analysis (WAVES 97) CY NOV 03-07, 1997 CL VIRGINIA BEACH, VA SP Coastal Zone Fdn, Amer Soc Civil Engineers, Coastal Zone Management omm, Waves & Wave Forces Comm, Rubble Mound Struct Comm AB This paper presents results of laboratory model tests on a vertical wave barrier using transient waves generated from a standard wave spectrum. With these transient waves, a typical model test can be conducted in less than one minute and can yield complete spectral information for wave transmission, wave reflection, and wave forces on the barrier. Results of these short transient wave tests are shown to compare favorably to results of more laborious tests using regular waves. Other advantages of transient waves are then discussed. C1 USN Acad, Hydromech Lab, Annapolis, MD 21402 USA. RP Kriebel, DL (reprint author), USN Acad, Hydromech Lab, 590 Holloway Rd St 11D, Annapolis, MD 21402 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0346-5 PY 1998 BP 1306 EP 1320 PG 3 WC Engineering, Marine; Engineering, Civil; Mechanics; Water Resources SC Engineering; Mechanics; Water Resources GA BN85F UT WOS:000083193400100 ER PT B AU Lambert, DN Walter, DJ Young, DC Griffin, SR Benjamin, KC AF Lambert, DN Walter, DJ Young, DC Griffin, SR Benjamin, KC GP IEEE IEEE TI Developments in acoustic sediment classification SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc AB This paper describes several recent developments which improve the seafloor characterization and sediment classification capabilities of a state-of-the-art high resolution subbottom profiling system designated the Acoustic Seafloor Classification System (ASCS). The ASCS has been under development by the Naval Research Laboratory since 1993. It was originally designed as a robust acoustic research tool with broad operational capabilities. Because of this, it has been a straightforward process to develop, integrate, and test new hardware, software. and sediment classification algorithms with the system. Over the past five years, a number of basic and applied research projects have provided the impetus and means to make significant improvements in the system resolution, sediment property prediction capability, and overall system operation. Two broadband, constant beam width transducers have been developed to increase vertical and spatial resolution of the seafloor for sediment classification purposes. The ASCS software has been rewritten in the C programming language and enhanced to improve data acquisition, data storage, signal processing, data display, automated mapping, and processing speed. A new version of the software is presently being written for Windows NT to provide easy fusion and simultaneous display of ASCS data with data from other environmental sensors such as a digital side scan sonar, expendable penetrometers, and laser line scan imagery. A new stable towbody has been developed which allows the mounting of several of these sensors on the platform for the collection of coregistered data. The general operational characteristics of the ASCS (narrow beam, high source level, wide bandwidth, and short pulse) have been found to be excellent for locating objects buried in the seafloor, e.g., pipelines. To exploit this capability further, new purpose-built parametric transducers, power amplifiers, multichannel electronics (for three transducer operation), and new data display software have been developed and tested. In addition, a new data inversion algorithm has been implemented. This algorithm is currently under test and is expected to provide a more accurate prediction of sediment geotechnical properties. Each of these developments is described in the following sections. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Lambert, DN (reprint author), USN, Res Lab, Code 7431, Stennis Space Ctr, MS 39529 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 26 EP 31 PG 6 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800007 ER PT B AU Kirsteins, IP Moura, JMF Fay, JW Mehta, SK AF Kirsteins, IP Moura, JMF Fay, JW Mehta, SK GP IEEE IEEE TI Ownship interference cancellation and source localization SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc AB Ownship radiated noise, direct and multipath, is a major source of interference that masks target signatures and makes them undetectable by classical techniques. It is especially a problem in the case of fast ship speeds and short tow cables in shallow water environments. In such cases, interference suppression techniques are needed to cancel this noise and unmask signals while maintaining a low false alarm rate. The paper shows that beamformers that account for the environmental conditions and suppress the interference provide substantial gains. Matching to the propagation conditions is particularly important. These gains become limited when the environment is progressively innacurately specified. C1 USN, Undersea Warfare Ctr, Newport Div, Newport, RI 02841 USA. RP Kirsteins, IP (reprint author), USN, Undersea Warfare Ctr, Newport Div, Code 3124,Code 3112, Newport, RI 02841 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 153 EP 157 PG 5 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800032 ER PT B AU Field, RL Broadhead, MK Peggion, G AF Field, RL Broadhead, MK Peggion, G GP IEEE IEEE TI The effects of a dynamic shallow water front on acoustic propagation. SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc AB This paper investigates the effects of a dynamic shallow water front on narrowband (1 Wt) and broadband (50 Hz bandwidth centered at 1 kHz) acoustic propagation. A generic shallow water front is simulated with the Princeton Ocean Model. The sound velocity field is calculated as a function of range, depth and time. A parabolic equation acoustic model is used to simulate acoustic propagation from the warm to the cold side of the front. When the front is in geostrophic balance, acoustic mode coupling is from the higher order, bottom-interacting modes to lower order modes that become trapped in the upper 50 meters of the water column. In the narrowband case, acoustic propagation across the front is enhanced by 10 to 15 dB in the upper 50 meters due to mode coupling. In the broadband case, the coupling from higher order to lower order modes mitigates the multipath, causing the pulse to emerge from the cold side of the front almost undistorted in the upper 50 meters. However when the front becomes unstable and begins to move, acoustic propagation becomes highly variable and the above effects may be observed only intermittently. The study shows that acoustic propagation across a shallow water front can change significantly over a period of hours and hence the need to consider the dynamics of fronts when trying to draw general conclusions about their effects on acoustic propagation. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Field, RL (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 209 EP 213 PG 5 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800044 ER PT B AU McDonald, VK Stevenson, JM Briest, SG Olson, JR AF McDonald, VK Stevenson, JM Briest, SG Olson, JR GP IEEE IEEE TI Autonomous buoyed environmental system SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc DE oceanographic sensors; transducers and arrays; positioning and control; communication AB The engineering development path of the Autonomous Buoyed Environmental Sensor (ABES) system is presented. Emphasis is on the placement of a micropower 6-bit microcontroller at each sensor, thereby enabling control, addressing, and data telemetry over a single conductor and allowing 12-bit digitization at each sensor. ABES is a lightweight, reconfigurable, integrated oceanographic measurement system intended to provide oceanographers with the opportunity to accomplish increased spatial sampling of the shallow-water ocean environment due to its ease of use and low cost compared to more traditional methods, albeit with slightly degraded accuracy and resolution. The instrument is a sensor string connected to a cylindrical electronics canister. The prototype sensor string contains one electromagnetic current meter, 3 tilt sensors, 3 magnetoresistive compasses, and 10 conductivity, temperature and depth sensors, the latter developed in conjunction with Ocean Sensors, Inc. These sensors are distributed along a 40-m cable. A system controller, GPS receiver, and spread-spectrum radio are housed in the 1-m long electronics canister. Together, these components weigh 10 kg in air and occupy a volume of 5 1. C1 USN, Space & Naval Warfare Syst Ctr, San Diego, CA 92152 USA. RP McDonald, VK (reprint author), USN, Space & Naval Warfare Syst Ctr, San Diego, CA 92152 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 549 EP 553 PG 5 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800113 ER PT B AU Stevenson, JM Briest, SG Fronk, AD AF Stevenson, JM Briest, SG Fronk, AD GP IEEE IEEE TI A spread-spectrum radio data link buoy for underwater sensing applications SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc DE underwater acoustics; sensor arrays; RF communication AB High data rate connectivity from an underwater sensor suite to a data acquisition platform has been demonstrated without the need to string vulnerable cable across a beach or up to a ship. Initial test results of a prototype data relay buoy coupled to a lightweight seafloor hydrophone array are described. Ranges of 5 km over water at a data rate of over 1 Mbps have been achieved. The buoy complements new technology in lightweight arrays and low-power RF digital communications from a small, expendable buoy. C1 USN, US Govt Space & Naval Warfare Syst Ctr, San Diego, CA 92152 USA. RP Stevenson, JM (reprint author), USN, US Govt Space & Naval Warfare Syst Ctr, San Diego, CA 92152 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 854 EP 856 PG 3 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800172 ER PT B AU Riedel, JS Healey, AJ AF Riedel, JS Healey, AJ GP IEEE IEEE TI Shallow water station keeping of AUVs using multi-sensor fusion for wave disturbance prediction and compensation SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc AB An important capability for Autonomous Underwater Vehicles (AUVs) is station keeping. Station keeping is the ability of a vehicle to maintain position and orientation with regard to a reference object. In shallow water this mission most likely Hill be disrupted by the large wave induced hydrodynamic forces acting on the vehicle. To counter this problem, knowledge of these wave induced disturbances is critical to allow for the design of a control system that will enable the vehicle to accurately navigate and position itself. The ability to develop a so called "predictive" control strategy for underwater vehicles is limited by the methods available to measure and predict the wave induced disturbances. Surface vessels may employ remote sensors such as acoustic probes, lasers or short wavelength radar to determine future disturbances, but this remote sensing is not feasible in a low cost underwater vehicle. AW control system design is limited to the use of on board sensors for disturbance prediction. In this paper, we present the design of a Sliding Mode Controller (SMC) that employs multisensor data fusion for wave disturbance prediction/estimation. Using data obtained from the vehicle's Doppler, Acoustic Doppler Velocimeter (ADV) and motion package, a dynamic filter is developed that will fuse the information from the various sensors and provide the controller with an estimate of the wave induced disturbance, thus allowing the vehicle to station keep in both heading and position with far greater accuracy. C1 USN, Postgrad Sch, Ctr AUV Res, Monterey, CA 93943 USA. RP Riedel, JS (reprint author), USN, Postgrad Sch, Ctr AUV Res, Monterey, CA 93943 USA. NR 10 TC 0 Z9 0 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 1064 EP 1068 PG 5 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800212 ER PT B AU Mayer, RH Monastero, FC AF Mayer, RH Monastero, FC GP IEEE IEEE TI Renewable energy source for Diego Garcia SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc AB The U. S. Navy desires to improve the reliability and reduce the cost of providing utility services at NSF Diego Garcia. To achieve these goals, the Navy intends to use a Public/Private Venture (PPV) agreement whereby a private entity will contract to replace and/or upgrade existing utility equipment. The PPV contractor will also be responsible for maintaining and operating such utilities for an anticipated period of 30 years. A Request for Proposals was issued in April 1998 and selection of the PPV contractor is anticipated by September 1998. Although contractors are at liberty to select the utility service method(s), strong encouragement has been given to use a renewable energy resource such as ocean thermal energy. This paper discusses the infrastructure needs on Diego Garcia, specific environmental issues of concern, and merits of various ocean energy technologies to meet the Navy's utility goals. The history of the competitive process which led to solicitation, receipt and evaluation of industry proposals is reviewed. Results of a student design competition to identify the ocean energy resource which best satisfies the utility needs of NSF Diego Garcia are also presented. C1 US Naval Acad, Dept Ocean Engn, Annapolis, MD 21012 USA. RP Mayer, RH (reprint author), US Naval Acad, Dept Ocean Engn, Annapolis, MD 21012 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 1432 EP 1435 PG 4 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800286 ER PT B AU Bishop, GC Smith, J AF Bishop, GC Smith, J GP IEEE IEEE TI Target-boundary scattering and resonant detection and classification SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc AB Several of the geometric and physical parameters of an elastic target may be determined from its resonance spectrum. Resonance scattering theory has shown that the form function for the resonance spectrum may be obtained by subtracting the form function for background scattering from the total form function. Although background form functions for free field scattering are well known, background form functions for scattering from targets near a planar boundary are not. In this paper, an interacting background form function is defined and a null field T-matrix formalism is used to calculate the resonance spectrum of fluid loaded elastic spherical shells near planar penetrable sediment boundaries. Results are compared with free field results to determine the ability of the interacting background to isolate free field resonances, to identify some of the effects of target-boundary scattering on the resonance spectrum, and the ability to determine target parameters. C1 USN, Undersea Warfare Ctr, Div Newport, Newport, RI 02841 USA. RP Bishop, GC (reprint author), USN, Undersea Warfare Ctr, Div Newport, Newport, RI 02841 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 1563 EP 1567 PG 5 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800312 ER PT B AU DeAngelis, CM Whitney, JE AF DeAngelis, CM Whitney, JE GP IEEE IEEE TI The Neurally-Inspired Contact Estimator (NICE) SO OCEANS'98 - CONFERENCE PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT IEEE OCEANS Conference and Exhibition on Engineering for Sustainable Use of the Oceans (OCEANS 98) CY SEP 28-OCT 01, 1998 CL NICE, FRANCE SP IEEE, IEEE Ocean Engn Soc AB The Neurally-Inspired Contact Estimator (NICE) is a signal processing system designed to perform target motion analysis, that is, source localization and tracking given a series of bearing observations. NICE is implemented using a custom neural network, which incorporates the characteristics of an object's motion parameters into the network weights. In this paper the relative fit between NICE and conventional probability theory is analyzed. C1 USN, Undersea Warfare Ctr, Newport, RI 02840 USA. RP DeAngelis, CM (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02840 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5045-6 PY 1998 BP 1619 EP 1623 PG 5 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BM30T UT WOS:000078340800323 ER PT B AU Andrews, JM Lieberman, SH AF Andrews, JM Lieberman, SH BE GarciaMartinez, R Brebbia, CA TI Multispectral fluorometric sensor for real time in-situ detection of marine petroleum spills SO OIL AND HYDROCARBON SPILLS, MODELLING, ANALYSIS AND CONTROL LA English DT Proceedings Paper CT 1st International Conference on Oil and Hydrocarbon Spills, Modelling, Analysis and Control CY JUL, 1998 CL SOUTHAMPTON, ENGLAND SP Wessex Inst Technol Southampton, Inst Mecanica Fluidos, Univ Cent Venezuela AB This paper describes the development of a fluorescence based in-situ sensor system for real time monitoring and detection of petroleum hydrocarbon contaminants in the marine environment. The system consists of an array of underwater sensors deployed just below the water surface. The sensors can detect floating product (surface sheen) from below the surface as well as detect emulsified or dissolved phase petroleum in the water column. Data from each of the sensors is transmitted to a central base station computer for display, logging, and analysis. The primary intended use of the system is to protect marine facilities from accidental petroleum discharges by providing responding authorities with immediate notification of the occurrence of a leak or spill. The detection of petroleum is based upon the fluorescence of polycyclic aromatic hydrocarbons found within petroleum derived products. The sensors utilize broadband ultraviolet excitation from a pulsed xenon lamp to generate fluorescence in contaminated sea water. The intensity of the resulting fluorescence emission is proportional to both the oil concentration in water, and/or the oil film thickness on the water surface. Multispectral fluorescence emission information is used to distinguish between several possible petroleum classes and eliminate false positive interference from non-petroleum based fluorophores such as chlorophyll. Real time qualitative identification yields an important advantage in terms of rapidly resolving questions of spill origin or in determining an appropriate response. To enable long term underwater deployment, the optical energy of the ultraviolet excitation source also serves to prevent the occurrence of biofouling on the surface of the optical window. The results of initial testing in San Diego Harbor and at the Ohmsett wave tank facility in New Jersey demonstrate the system's ability to detect petroleum products under a variety of conditions, including the presence of strong harbor. C1 USN, Space & Naval Warfare Syst Ctr San Diego, Environm Chem Biotechnol Branch D361, San Diego, CA 92152 USA. RP Andrews, JM (reprint author), USN, Space & Naval Warfare Syst Ctr San Diego, Environm Chem Biotechnol Branch D361, 53475 Strothe Rd, San Diego, CA 92152 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU COMPUTATIONAL MECHANICS PUBLICATIONS LTD PI SOUTHAMPTON PA ASHURST LODGE, SOUTHAMPTON S04 2AA, HANTS, ENGLAND BN 1-85312-526-1 PY 1998 BP 291 EP 301 PG 11 WC Engineering, Environmental; Engineering, Chemical; Engineering, Marine; Engineering, Petroleum; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BL96J UT WOS:000077293700026 ER PT S AU Nee, SMF AF Nee, SMF BE Datla, RV Hanssen, LM TI Measurement of refractive index of transparent materials using null polarimetry near Brewster angle SO OPTICAL DIAGNOSTIC METHODS FOR INORGANIC TRANSMISSIVE MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostic Methods for Inorganic Transmissive Materials CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE refractive index; transparent material; polarimetry; metrology AB The nondestructive measurement of refractive index of transmissive materials using null polarimetry is simple, accurate and does not require much on sample preparation. In null polarimetry, the ellipsometric parameter psi for reflection from a sample is measured psi for transparent material is defined by tan psi = r(p)/r(s) where r(p) and r(s) are coefficients of reflection for the p- and s-polarization respectively. By choosing the angle of incidence theta near the Brewster angle, refractive index can be computed from theta and psi directly. The only requirement on the sample is that no back surface reflection is allowed to mess up the front surface reflection. Precision in the refractive index is about 0.0004. Spectra of refractive index for quartz are measured and compared with the spectra quoted from existing Handbooks. C1 USN, Ctr Weap Div, Phys Branch, Res & Technol Grp, China Lake, CA 93555 USA. RP Nee, SMF (reprint author), USN, Ctr Weap Div, Phys Branch, Res & Technol Grp, China Lake, CA 93555 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2880-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3425 BP 247 EP 257 PG 11 WC Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BM03R UT WOS:000077457500028 ER PT S AU Mattoussi, H Rodriguez-Viejo, J Jensen, KF Bawendi, MG Rubner, MF AF Mattoussi, H Rodriguez-Viejo, J Jensen, KF Bawendi, MG Rubner, MF BE Kafafi, ZH TI Electroluminescence and cathodoluminescence from inorganic CdSe nanocrystals embedded in thin films SO ORGANIC LIGHT-EMITTING MATERIALS AND DEVICES II SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Organic Light-Emitting Materials and Devices II CY JUL 21-23, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers ID LIGHT-EMITTING-DIODES; QUANTUM-DOT COMPOSITES; CADMIUM SELENIDE NANOCRYSTALS; POLY(P-PHENYLENE VINYLENE); SEMICONDUCTING POLYMER; PHOTOLUMINESCENCE; CRYSTALLITES; ENHANCEMENT; SPECTRUM; GLASS AB Electroluminescence (EL) from heterostructure devices made of organic poly (phenylene vinylene), PPV, and inorganic semiconductor CdSe nanocrystals have been investigated, along with cathodoluminescence (CL) from thin films of ZnS doped with CdSe-ZnS core-shell nanocrystals. In the EL devices, the organic PPV structure, built next to the anode using the technique of molecular layer-by-layer sequential adsorption, serves as the hole transport layer. The inorganic layer, adjacent to the electrode and made of spin cast CdSe nanocrystals passivated with either organic groups or with a thin layer of ZnS, is the emitting layer. The ZnS host film in the CL devices, built using chemical vapor deposition, serves as the support medium for the dispersed nanocrystals, but also provides additional passivation to the surface of those nanocrystals. We find that the EL and CL signals almost exclusively originate from the inorganic nanocrystals in both cases, i.e., EL comes fi om the nanocrystal layer in the heterostructure device while CL is generated from the dispersed particles in the composite film. The external EL quantum efficiency, eta(EL), is not enhanced by the presence of ZnS overcoating, opposed to the observed increase in the photoluminescence (PL) quantum yield. However, we find that the CL emission and its stability are substantially improved by the presence of ZnS around the emitting nanocrystal cores. These observations reflect a difference in the effects of overcoating on the various luminescence processes. On the one hand, a ZnS overlayer is associated with an additional energetic barrier that reduces the efficiency of charge injection into the nanocrystals for EL. On the other hand, PL and CL processes only benefit from the surface passivation with ZnS. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Mattoussi, H (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. EM hedimat@ccs.nrl.navy.mil RI Rodriguez-Viejo, Javier/G-1488-2016 OI Rodriguez-Viejo, Javier/0000-0002-9735-263X NR 34 TC 1 Z9 1 U1 0 U2 8 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2931-7 J9 PROC SPIE PY 1998 VL 3476 BP 310 EP 321 DI 10.1117/12.332627 PG 12 WC Chemistry, Applied; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics; Physics, Applied SC Chemistry; Materials Science; Optics; Physics GA BM33B UT WOS:000078397300035 ER PT S AU Roberts, MJ Stenger-Smith, JD Zarras, P Hollins, RA Nadler, M Chafin, AP Wynne, KJ Lindsay, GA AF Roberts, MJ Stenger-Smith, JD Zarras, P Hollins, RA Nadler, M Chafin, AP Wynne, KJ Lindsay, GA BE Frank, CW TI Nonlinear optical films from pairwise-deposited semiionomeric syndioregic polymers SO ORGANIC THIN FILMS: STRUCTURE AND APPLICATIONS SE ACS SYMPOSIUM SERIES LA English DT Article; Proceedings Paper CT Symposium on Organic Thin Films held at the 213th National Meeting of the American-Chemical-Society CY APR 13-17, 1997 CL SAN FRANCISCO, CALIFORNIA SP Amer Chem Soc ID LANGMUIR-BLODGETT-FILMS AB Polar multilayer films of syndioregic nonlinear optical polymers were made using Langmuir-Blodgett-Kuhn (LBK) deposition of a polymeric salt formed at the water surface from two complementary polymers (a polycation insoluble in water and a water-soluble polyanion). Noncentrosymmetric order in the deposited films is maintained primarily by ionic and hydrogen bonding. An important advantage of using LBK technique to produce all-polymeric nonlinear optical films is it allows polymers to be processed near room temperature thus avoiding the disordering and degrading effects seen in high temperature electric field poling. In addition, the LBK technique offers control over final film thickness to within one monolayer and materials may be precisely located within the film to control properties for purposes such as phase matching of the fundamental and second harmonic waveguide modes. A well-known limitation, the long-standing problem of low thermal structural stability of LBK films, may be solved by using high Tg polymers. However, a serious limitation of LBK technique remains; namely, the long processing time required to build up films of sufficient thickness (>0.5 micrometers) for waveguiding. In principle, the pairwise deposition technique reported here will increase the rate of film thickness growth. C1 NAWC, Res & Technol Grp, China Lake, CA 93555 USA. Off Naval Res, Arlington, VA 22217 USA. RP Roberts, MJ (reprint author), NAWC, Res & Technol Grp, Code 4B2200D,1 Adm Circle, China Lake, CA 93555 USA. NR 20 TC 2 Z9 2 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 SIXTEENTH ST NW, WASHINGTON, DC 20036 USA SN 0097-6156 BN 0-8412-3564-3 J9 ACS SYM SER PY 1998 VL 695 BP 267 EP 287 PG 21 WC Chemistry, Multidisciplinary; Chemistry, Organic; Materials Science, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Polymer Science GA BQ26Q UT WOS:000087751800020 ER PT J AU Brooker, CR Hunsaker, DH Zimmerman, AA AF Brooker, CR Hunsaker, DH Zimmerman, AA TI A new anesthetic system for microlaryngeal surgery SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 18-21, 1994 CL SAN DIEGO, CALIFORNIA SP Amer Acad Otolaryngol Head & Neck Surg ID JET VENTILATION; OBSTRUCTION; TUBES AB Anesthesia for microlaryngeal surgery creates many obstacles for the anesthesiologist and otolaryngologist, Anesthetic techniques developed to improve surgical exposure have been met with significant limitations and are difficult for the anesthesiologist to monitor. A new subglottic jet ventilation anesthesia system is introduced that meets the needs of the otolaryngologist and the anesthesiologist. This new system is made up of two components: (1) The Hunsaker Mon-Jet tube is a laser-safe, subglottic jet ventilation tube constructed of a nonflammable fluoroplastic material, It allows monitoring of tracheal pressure and end tidal carbon dioxide, and it is designed with a basket-shaped distal extension to align the jet port away from the tracheal mucosa and to prevent trauma and submucosal injection of jetted gas, (2) An automatic jet ventilator, which has an adjustable respiratory rate, inspiratory/expiratory ratio, and flow rate, also monitors expiratory end peak airway pressures and has an automatic shutdown feature if either of these pressures are exceeded, This system was successfully used in 36 patients undergoing microlaryngeal surgery. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Otolaryngol, San Diego, CA 92134 USA. USN, Med Ctr, Dept Anesthesiol, San Diego, CA 92134 USA. RP Brooker, CR (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 16 TC 14 Z9 19 U1 0 U2 1 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD JAN PY 1998 VL 118 IS 1 BP 55 EP 60 DI 10.1016/S0194-5998(98)70375-4 PG 6 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA YT003 UT WOS:000071554300010 PM 9450829 ER PT J AU Randall, DA Hoffer, ME AF Randall, DA Hoffer, ME TI Complications of tonsillectomy and adenoidectomy SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article ID POST-TONSILLECTOMY; PULMONARY-EDEMA; PEDIATRIC TONSILLECTOMY; OUTPATIENT PROCEDURE; LASER TONSILLECTOMY; AIRWAY-OBSTRUCTION; LOCAL-ANESTHESIA; CHILDREN; ADENOTONSILLECTOMY; HEMORRHAGE AB Adenotonsillectomy is generally safe surgery, but surgeons should be cognizant of potential complications and be prepared to manage them, Postoperative hemorrhage usually responds to local measures or cautery but can be life-threatening. Preoperative screening of coagulation profiles appears unnecessary, Anesthetic risks have declined with modern techniques, but airway risks, aspiration, and pulmonary edema are possible, Nasopharyngeal valving may be altered by velopharyngeal incompetence or nasopharyngeal stenosis, Sore throat, otalgia, fever, dehydration, and uvular edema are more common postoperative complaints. Less common complications include atlantoaxial subluxation, mandible condyle fracture, infection, eustachian tube injury, and psychological trauma, The prevalence, management, and strategies for avoidance of these are discussed. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Otolaryngol, San Diego, CA 92134 USA. RP Randall, DA (reprint author), USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. NR 93 TC 169 Z9 172 U1 1 U2 10 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0194-5998 EI 1097-6817 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD JAN PY 1998 VL 118 IS 1 BP 61 EP 68 DI 10.1016/S0194-5998(98)70376-6 PG 8 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA YT003 UT WOS:000071554300011 PM 9450830 ER PT S AU Goins, B Klipper, R Martin, C Jerabek, PA Khalvati, S Fox, PT Cliff, RO Kwasiborski, V Rudolph, AS Phillips, WT AF Goins, B Klipper, R Martin, C Jerabek, PA Khalvati, S Fox, PT Cliff, RO Kwasiborski, V Rudolph, AS Phillips, WT BE Hudetz, AG Bruley, DF TI Use of oxygen-15-labeled molecular oxygen for oxygen delivery studies of blood and blood substitutes SO OXYGEN TRANSPORT TO TISSUE XX SE ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY LA English DT Article; Proceedings Paper CT 25th Annual Meeting of the International-Society-on-Oxygen-Transport-to-Tissue (ISOTT) CY AUG 19-23, 1997 CL MILWAUKEE, WISCONSIN SP Marquette Med Syst, Alliance Pharmaceut Corp, Glaxo Wellcome Inc, GE Med Syst, Opt Sensors Inc, Dept Anesthesiol, MCW C1 Univ Texas, Hlth Sci Ctr, Dept Radiol, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Res Imaging Ctr, San Antonio, TX 78284 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Goins, B (reprint author), Univ Texas, Hlth Sci Ctr, Dept Radiol, San Antonio, TX 78284 USA. RI Goins, Beth/F-1311-2010; Phillips, William/E-8427-2010; Fox, Peter/B-4725-2010 OI Phillips, William/0000-0001-8248-7817; Fox, Peter/0000-0002-0465-2028 FU NHLBI NIH HHS [R01HL53052] NR 13 TC 2 Z9 2 U1 0 U2 1 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0065-2598 BN 0-306-46043-2 J9 ADV EXP MED BIOL JI Adv.Exp.Med.Biol. PY 1998 VL 454 BP 643 EP 652 PG 10 WC Biotechnology & Applied Microbiology; Medicine, Research & Experimental; Physiology SC Biotechnology & Applied Microbiology; Research & Experimental Medicine; Physiology GA BL97G UT WOS:000077323800077 PM 9889945 ER PT B AU Konoske, P Deniston, W Barker, R Moses, D AF Konoske, P Deniston, W Barker, R Moses, D BE Nelson, R Gelish, A Mun, SK TI Evaluation of the Mobile Medical Monitor (M3) in a field environment SO PACIFIC MEDICAL TECHNOLOGY SYMPOSIUM, PROCEEDINGS LA English DT Proceedings Paper CT Pacific Medical Technology Symposium (PACMEDTek) CY AUG 17-21, 1998 CL HONOLULU, HI SP Tripler Army Med Ctr AB The delivery of state-of-the-art medical care to deployed forces continues to be a top priority for the U.S. Navy and U.S. Marine Corps. To support this priority, the Navy assembled a suite of clinical sensors and accompanying administrative and communications software in a rugged mobile modular computer unit for field use. The 1(st) Medical Battalion Camp Pendleton, San Diego, CA participated in field testing of the Mobile Medical Monitor (M3) unit. The users commenced that the clinical sensors worked well and allowed for easy storage of data, but that the M3 should allow for multiple patients to be monitored by a single computer and should include a relational database. Future development of the system will incorporate the user recommendations. C1 USN, Hlth Res Ctr, San Diego, CA 92152 USA. RP Konoske, P (reprint author), USN, Hlth Res Ctr, San Diego, CA 92152 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-8186-8667-7 PY 1998 BP 83 EP 92 DI 10.1109/PACMED.1998.767929 PG 4 WC Computer Science, Interdisciplinary Applications; Medical Informatics SC Computer Science; Medical Informatics GA BN33G UT WOS:000081642800014 ER PT S AU Irey, PM Hott, RW Marlow, DT AF Irey, PM Hott, RW Marlow, DT BE Rolim, J TI An architecture for network resource monitoring in a distributed environment SO PARALLEL AND DISTRIBUTED PROCESSING SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 10 IPPS/SPDP 98 Workshops Held in Conjunction with the 12th International Parallel Processing Symposium / 9th Symposium on Parallel Distributed Processing CY MAR 30-APR 03, 1998 CL ORLANDO, FLORIDA SP IEEE, Comp soc AB As part of its HiPer-D Program, the United States Navy is developing an experimental distributed system which achieves survivability by dynamically reconfiguring the system using replicated system components and resources. To enable the reconfiguration, resource monitors observe the behavior of the system and report this information to a resource manager. The resource manager makes reconfiguration decisions based on this information. Because all I reconfiguration decisions are based on data obtained from resource monitors and the network is the common resource linking all components in the distributed system, this paper focuses specifically on network resource monitoring. A generalized network resource monitor architecture is proposed. Two instantiations of this architecture are then presented The first is based oil custom developed tools tailored to a specific application while the second is based on commercially available products (e.g. SNMP, RMON; etc.). Scalability, intrusiveness, and fidelity are identified as evaluation criteria against which implementation trade-offs are made. This paper presents the results of initial experiments as well as future research directions. C1 USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Irey, PM (reprint author), USN, Ctr Surface Warfare, DD Code B35,17320 Dahlgren Rd, Dahlgren, VA 22448 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-64359-1 J9 LECT NOTES COMPUT SC PY 1998 VL 1388 BP 1153 EP 1163 PG 11 WC Computer Science, Theory & Methods SC Computer Science GA BM09F UT WOS:000077612600118 ER PT S AU Ramsey, CL De Jong, KA Grefenstette, JJ Wu, AS Burke, DS AF Ramsey, CL De Jong, KA Grefenstette, JJ Wu, AS Burke, DS BE Eiben, AE Back, T Schoenauer, M Schwefel, HP TI Genome length as an evolutionary self-adaptation SO PARALLEL PROBLEM SOLVING FROM NATURE - PPSN V SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 5th International Conference on Parallel Problem Solving from Nature (PPSN V) CY SEP 27-30, 1998 CL AMSTERDAM, NETHERLANDS SP European Network Excellence Evolutionary Computat, Informatik Centrum Dortmund, Inst Programming Technol & Algorithm, Int Soc Genet Algorithms, Leiden Ctr Nat Comp, Municipal Amsterdam, Philips Siemens AG, Stichting European Evolutionary Comp Conf AB There is increasing interest ill evolutionary algorithms that leave variable-length genomes and/or location independent genes. However, our understanding of such algorithms both theoretically and empirically is much less well developed than the more traditional fixed-length, fixed-location ones. Recent studies with VIV (Virtual Virus), a variable! length, GA-based computational model of viral evolution, have revealed several emergent phenomena of both biological anti computational interest. One interesting and somewhat surprising result is that the length of individuals in the population self-adapts in direct response to the mutation rate applied, so the GA adaptively strikes the balance it needs to successfully solve the problem. Over a broad range of mutation rates, genome length tends to increase dramatically ill the early phases of evolution, and then decrease to a level based on the mutation rate. The plateau genome length (i.e., the average length of individuals in the final population) generally increases in response to air increase in the base mutation rate. Furthermore, the mutation operator rate and adapted length resulting in the: best problem solving performance is about one mutation per individual. This is also the rate at which mutation generally occurs in biological systems; suggesting an optimal, or at least biologically plausible, balance of these operator rates. These results suggest that an important property of these algorithms is a considerable degree of self-adaptation. C1 USN, Res Lab, Washington, DC 20375 USA. George Mason Univ, Dept Comp Sci, Fairfax, VA 22030 USA. George Mason Univ, Inst Biosci Bioinformat & Biotechnol, Fairfax, VA 22030 USA. Johns Hopkins Univ, Ctr Immunizat Res, Baltimore, MD USA. RP Ramsey, CL (reprint author), USN, Res Lab, Code 5514, Washington, DC 20375 USA. OI /0000-0002-5704-8094 NR 23 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65078-4 J9 LECT NOTES COMPUT SC PY 1998 VL 1498 BP 345 EP 353 PG 9 WC Computer Science, Theory & Methods SC Computer Science GA BN73W UT WOS:000082774900034 ER PT S AU Potter, MA De Jong, KA AF Potter, MA De Jong, KA BE Eiben, AE Back, T Schoenauer, M Schwefel, HP TI The coevolution of antibodies for concept learning SO PARALLEL PROBLEM SOLVING FROM NATURE - PPSN V SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 5th International Conference on Parallel Problem Solving from Nature (PPSN V) CY SEP 27-30, 1998 CL AMSTERDAM, NETHERLANDS SP European Network Excellence Evolutionary Computat, Informatik Centrum Dortmund, Inst Programming Technol & Algorithm, Int Soc Genet Algorithms, Leiden Ctr Nat Comp, Municipal Amsterdam, Philips Siemens AG, Stichting European Evolutionary Comp Conf AB We present a novel approach to concept. learning in which a coevolutionary genetic algorithm is applied to the construction of an immune system whose antibodies can discriminate beta gen examples and counter-examples of a given concept. This approach is more general than traditional symbolic approaches to concept learning and fan be applied in situations where preclassified training examples are not, necessarily available. An experimental study is described in which a coevolutionary immune system adapts itself to one of the standard machine learning data sets. The resulting immune system concept description and a description produced by a traditional symbolic concept learner are compared and contrasted. C1 USN, Res Lab, Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. George Mason Univ, Dept Comp Sci, Fairfax, VA 22030 USA. RP Potter, MA (reprint author), USN, Res Lab, Ctr Appl Res Artificial Intelligence, Code 5510, Washington, DC 20375 USA. NR 12 TC 24 Z9 27 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65078-4 J9 LECT NOTES COMPUT SC PY 1998 VL 1498 BP 530 EP 539 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BN73W UT WOS:000082774900052 ER PT S AU Downs, F Wood, J Blume, B Smith, R AF Downs, F Wood, J Blume, B Smith, R BE Smith, RM TI Passive millimeter wave imaging device for naval special warfare SO PASSIVE MILLIMETER-WAVE IMAGING TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Passive Millimeter-Wave Imaging Technology II CY APR 13, 1998 CL ORLANDO, FL SP SPIE DE passive millimeter wave; sensor C1 USN, Coastal Syst Stn, Panama City, FL 32401 USA. RP Downs, F (reprint author), USN, Coastal Syst Stn, Panama City, FL 32401 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2827-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3378 BP 20 EP 26 DI 10.1117/12.319401 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL67W UT WOS:000076298300003 ER PT S AU Ashton, RW Ciezki, JG Badorf, MG AF Ashton, RW Ciezki, JG Badorf, MG GP IEEE IEEE IEEE TI The synthesis and hardware validation of DC-to-DC converter feedback controls SO PESC 98 RECORD - 29TH ANNUAL IEEE POWER ELECTRONICS SPECIALISTS CONFERENCE, VOLS 1 AND 2 SE IEEE POWER ELECTRONICS SPECIALISTS CONFERENCE RECORDS LA English DT Proceedings Paper CT 29th Annual IEEE Power Electronics Specialists Conference CY MAY 17-22, 1998 CL FUKUOKA, JAPAN SP IEEE Power Electr Soc, IEICE Japan, EIC, IEEJ, IEI Japan AB The authors present a modified multiloop algorithm including feedforward and droop for controlling a 9kW buck chopper. The state feedback pole selection is based on a prototype Bessel function model. The design incorporates tradeoffs in chopper hardware parameters and pole locations. Hardware and simulation results are presented. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Ashton, RW (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0275-9306 BN 0-7803-4489-8 J9 IEEE POWER ELECTRON PY 1998 BP 65 EP 71 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA BM09H UT WOS:000077614400010 ER PT S AU Ciezki, JG Ashton, RW AF Ciezki, JG Ashton, RW GP IEEE IEEE IEEE TI The design of stabilizing controls for shipboard DC-to-DC buck choppers using feedback linearization techniques SO PESC 98 RECORD - 29TH ANNUAL IEEE POWER ELECTRONICS SPECIALISTS CONFERENCE, VOLS 1 AND 2 SE IEEE POWER ELECTRONICS SPECIALISTS CONFERENCE RECORDS LA English DT Proceedings Paper CT 29th Annual IEEE Power Electronics Specialists Conference CY MAY 17-22, 1998 CL FUKUOKA, JAPAN SP IEEE Power Electr Soc, IEICE Japan, EIC, IEEJ, IEI Japan AB Motivated by the Navy's interest in developing a DC Zonal Electrical Distribution System, the authors have formulated a de-to-de buck chopper nonlinear control law to guarantee local asymptotic stability for a range of admissible constant power, variable input capacitance loads. Constant power nonlinearity is eliminated by pseudolinearization. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Ciezki, JG (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 20 Z9 20 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0275-9306 BN 0-7803-4489-8 J9 IEEE POWER ELECTRON PY 1998 BP 335 EP 341 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA BM09H UT WOS:000077614400050 ER PT J AU Chang, JH Beal, EJ Stalick, WM Mushrush, GW AF Chang, JH Beal, EJ Stalick, WM Mushrush, GW TI Fuel system icing inhibitors: The synthesis of esters of oxaacids SO PETROLEUM SCIENCE AND TECHNOLOGY LA English DT Article ID ETHER AB Currently ethylene glycol mono methyl ether (EGME) and diethylene glycol mono methyl ether (DiEGME) are used as fuel system icing inhibitor additives in both military and commercial aircraft. These compounds are toxic at the concentrations that required for effective deicing. When fuel systems sumps, filters and storage tanks are drained, they contain EGME/DiEGME and create hazards for personnel. Ethyl esters synthesized from oxaacids have been identified as possible fuel system icing inhibitor additive replacements. These compounds were synthesized from oxaacids and ethanol by an acid catalyzed Fischer esterfication method. The products were identified by infrared spectrometry, nuclear magnetic resonance spectrometry, and elemental analysis. Physical characterization included boiling point determination and refractive index. The tested oxaesters were found to be fuel stable for at least two years by accelerated storage tests. Octanol-water partition coefficients were determined and indicate the compounds have a higher solubility in fuel than in water. These oxaesters are predicted to be non-toxic. C1 George Mason Univ, Dept Chem, Fairfax, VA 22030 USA. Pk View High Sch, Sterling, VA 20165 USA. USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. RP Chang, JH (reprint author), Pk View High Sch, Sterling, VA 20165 USA. NR 18 TC 1 Z9 1 U1 1 U2 5 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1091-6466 J9 PET SCI TECHNOL JI Pet. Sci. Technol. PY 1998 VL 16 IS 9-10 BP 979 EP 1000 DI 10.1080/10916469808949821 PG 22 WC Energy & Fuels; Engineering, Chemical; Engineering, Petroleum SC Energy & Fuels; Engineering GA 137YA UT WOS:000076943600005 ER PT J AU Twigg, ME Bennett, BR Thibado, PM Shanabrook, BV Whitman, LJ AF Twigg, ME Bennett, BR Thibado, PM Shanabrook, BV Whitman, LJ TI Interfacial disorder in InAs/GaSb superlattices SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; PLANAR VIBRATIONAL-MODES; MOLECULAR-BEAM EPITAXY; GASB/INAS SUPERLATTICES; GA1-XINXSB/INAS SUPERLATTICES; SEMICONDUCTOR INTERFACES; ELECTRON-MICROSCOPY; QUANTUM-WELLS; GROWTH; ROUGHNESS AB We have addressed the question of interfacial disorder in InAs/GaSb superlattices (SLs) grown by molecular-beam epitaxy using high-resolution transmission electron microscopy, Raman spectroscopy, X-ray diffraction, and in-situ scanning tunnelling microscopy (STM). Our analysis indicates that InSb-like interfaces have a roughness of 1 monolayer (ML), for a SL grown on a GaSb buffer layer. For GaAs-like interfaces, however, the interface roughness is found to be 2 ML when the SL is grown on a GaSb buffer. For SLs grown on an InAs buffer, the roughness of GaAs-like interfaces (3 ML) is also greater than that of InSb-like interfaces (2 ML). These results suggest two general observations. The first is that GaAs-like interfaces are rougher than InSb-like interfaces. This difference may be due to the high surface energy of GaAs compared with InSb or to differences in surface kinetics. These observations are supported by in-situ STM results showing that the growth front surface morphology, for both GaSb and InAs layers, is rougher for GaAs-like interfaces than for InSb-like interfaces. We have also found that interface roughness is greater for an InAs/GaSb SL grown on an InAs buffer layer than for the same SL grown on a GaSb buffer layer. This difference in interface roughness may arise because InAs SL layers are in tension when grown on a GaSb buffer layer, whereas GaSb SL layers are under compression when grown on an InAs buffer layer. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. Univ Arkansas, Dept Phys, Fayetteville, AR 72701 USA. RP Twigg, ME (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008; Whitman, Lloyd/G-9320-2011 OI Bennett, Brian/0000-0002-2437-4213; Whitman, Lloyd/0000-0002-3117-1174 NR 48 TC 18 Z9 18 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD JAN PY 1998 VL 77 IS 1 BP 7 EP 30 PG 24 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA YT346 UT WOS:000071592400002 ER PT J AU Ngai, KL AF Ngai, KL TI Evidence of interaction between oxygen ions from conductivity relaxation and quasielastic light scattering data of yttria-stabilized zirconia SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID NON-ARRHENIUS CONDUCTIVITY; FREQUENCY RELAXATION; NEUTRON-SCATTERING; CONDUCTORS; GLASS; ELECTROLYTES; EXPLANATION; CROSSOVER; DYNAMICS; SPECTRA AB The appearances of two distinct activation energies at high and low temperatures, an anomalously high attempt frequency and a stretched-exponential time correlation function at low temperatures for oxygen-ion diffusion in yttria-stabilized zirconia (YSZ) are shown to be quantitatively consistent with the predictions of the coupling model. These anomalies, which occur in conductivity relaxation and quasielastic light scattering data, are caused by interactions between the diffusing oxygen ions in YSZ. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ngai, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 36 TC 45 Z9 45 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD JAN PY 1998 VL 77 IS 1 BP 187 EP 195 PG 9 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA YT345 UT WOS:000071592300014 ER PT J AU Scales, WA Ganguli, G Bernhardt, PA Lampe, M AF Scales, WA Ganguli, G Bernhardt, PA Lampe, M TI Wave generation associated with dust cloud expansion into a plasma SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT International Topical Conference on Plasma Physics - New Perspectives of Collective Effects CY NOV 10-14, 1997 CL TRIESTE, ITALY SP ASICTP, IUPAP AB Wave generation associated with the expansion of a dust cloud into a background plasma across a magnetic field is studied by using numerical simulation and theoretical models. As the dust grains expand across the magnetic field into the background plasma and charge up, an ambipolar electric field develops across the boundary layer between the negatively charged dust cloud and the background plasma. A strongly sheared electron E x B flow develops along the boundary. Plasma irregularities develop in response to the sheared electron flow velocity. It is noted that these irregularities are observed in the dust grain charge as well as the background plasma electron and ion densities. The fluctuations in dust grain charge are interpreted to be a fundamental collective effect in the dusty plasma produced by the dust cloud expansion. A theoretical model for the shear-driven instability in the dust cloud boundary is presented. In general the theoretical model predictions show good agreement with the numerical simulation results. C1 Virginia Polytech Inst & State Univ, Bradley Dept Elect & Comp Engn, Blacksburg, VA 24061 USA. USN, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. RP Scales, WA (reprint author), Virginia Polytech Inst & State Univ, Bradley Dept Elect & Comp Engn, Blacksburg, VA 24061 USA. NR 7 TC 6 Z9 6 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1998 VL T75 BP 238 EP 240 DI 10.1238/Physica.Topical.075a00238 PG 3 WC Physics, Multidisciplinary SC Physics GA 112AZ UT WOS:000075472700058 ER PT J AU Freeland, JW Grigorov, IL Walker, JC AF Freeland, JW Grigorov, IL Walker, JC TI Magnetic phase transition in epitaxial Ni1-xFex alloy thin films SO PHYSICAL REVIEW B LA English DT Article ID FE FILMS; FCC IRON; CU(100); ANTIFERROMAGNETISM; FERROMAGNETISM; CU(001) AB An investigation of fee Ni1-xFex thin films utilizing a combination of Mossbauer spectroscopy and magnetometry twenty presents clear evidence for the emergence of a low-spin antiferromagnetic state in the region of high Fe concentration, which coexists with a high-spin ferromagnetic state. The emergence of this state is observed by magnetometry as a drop in the saturation moment while Mossbauer spectroscopy reveals the appearance of a low-spin antiferromagnetic state. Evidence of superparamagnetic behavior indicates that the portion of the sample in the high-spin state may exist as clusters in a matrix of the low-spin state. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Freeland, JW (reprint author), USN, Brookhaven Natl Lab, Res Lab, NSLS Bldg,725A-U4B, Upton, NY 11973 USA. NR 30 TC 37 Z9 37 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 1 PY 1998 VL 57 IS 1 BP 80 EP 83 DI 10.1103/PhysRevB.57.80 PG 4 WC Physics, Condensed Matter SC Physics GA YP839 UT WOS:000071320800021 ER PT J AU Singh, DJ Pickett, WE AF Singh, DJ Pickett, WE TI Pseudogaps, Jahn-Teller distortions, and magnetic order in manganite perovskites SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; LA1-XCAXMNO3 SYSTEM; DOUBLE EXCHANGE; MAGNETORESISTANCE; TRANSPORT; RESISTIVITY; TL2MN2O7; FILMS AB Local spin-density calculations are used to investigate the relationship between lattice distortions, magnetic ordering, and electronic properties in manganite perovskites. Lattice distortions are found to open pseudogaps at the middle of the majority spin e(g) manifold, which are more directly related to rotations than Jahn-Teller distortion. Because the pseudogap is narrow, its effect on transport is strongly dependant on doping, falling off due to Fermi-level motion as La is replaced by divalent ions in LaMnO3. Structural relaxations provide evidence that unlike pure LaMnO3, lattice distortions in the ferromagnetically-ordered colossal-magnetoresistance (CMR) regime are relatively weakly coupled to electronic properties. These results an discussed in relation to the CMR effect. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Singh, DJ (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RI Singh, David/I-2416-2012 NR 28 TC 63 Z9 63 U1 0 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 1 PY 1998 VL 57 IS 1 BP 88 EP 91 DI 10.1103/PhysRevB.57.88 PG 4 WC Physics, Condensed Matter SC Physics GA YP839 UT WOS:000071320800023 ER PT J AU Mazin, II Liechtenstein, AI AF Mazin, II Liechtenstein, AI TI Location of holes in Y1-xPrxBa2Cu3O7 SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTIVITY; SUPPRESSION; PRBA2CU3O7; MODEL AB Recent experiments by Merz er al. [Phys. Rev. B 55, 9160 (1997)] demonstrated that the loss of superconductivity upon Pr doping is associated with the change of the character of the oxygen holes from p(sigma) to p(pi). This experiment sheds light onto the long-standing problem of T-c suppression by Pr, and helps to rule out a number of theoretical models, leaving only those which predict such a transfer of the O holes. To distinguish between the two models that do predict such an effect, one has to access the ratio of the planar and axial character of the holes. We do so in this paper. C1 USN, Res Lab, Washington, DC 20375 USA. George Mason Univ, CSI, Fairfax, VA 22030 USA. Forschungszentrum Julich, Julich, Germany. RP USN, Res Lab, Code 6691, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Lichtenstein, Alexander/K-8730-2012 OI Lichtenstein, Alexander/0000-0003-0152-7122 NR 11 TC 22 Z9 22 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN 1 PY 1998 VL 57 IS 1 BP 150 EP 152 DI 10.1103/PhysRevB.57.150 PG 3 WC Physics, Condensed Matter SC Physics GA YP839 UT WOS:000071320800039 ER PT J AU Rudd, RE Pickett, WE AF Rudd, RE Pickett, WE TI Single-spin superconductivity: Formulation and Ginzburg-Landau theory SO PHYSICAL REVIEW B LA English DT Article ID HALF-METALLIC FERROMAGNET; RENORMALIZATION-GROUP; ANISOTROPIC SUPERCONDUCTORS; POSITRON-ANNIHILATION; SYMMETRY; HE-3; TRANSPORT; SR2RUO4; NIMNSB; CRO2 AB We describe a superconducting phase that arises due to a pairing instability of the half-metallic antiferromagnetic (HM AFM) normal state. This single-spin superconducting (SSS) phase contains broken time-reversal symmetry in addition to broken gauge symmetry, the former due to the underlying magnetic order in the normal state. A classification of normal-state symmetries leads to the conclusion that the HM AFM normal phase whose point group contains the inversion operator contains the least symmetry possible which still allows for a zero momentum pairing instability. The Ginzburg-Landau free energy for the superconducting order parameter is constructed consistent with the symmetry of the normal phase, electromagnetic gauge invariance and the crystallographic point-group symmetry including inversion. For cubic, hexagonal, and tetragonal point groups, the possible symmetries of the superconducting phase are classified, and the free energy is used to construct a generalized phase diagram. We identify the leading candidate out of the possible SSS phases for each point group. The symmetry of the superconducting phase is used to determine the cases where the gap function has generic zeros (point or line nodes) on the Fermi surface. Such nodes always occur, hence thermodynamic properties will have power-law behavior at low temperature. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20774 USA. RP Rudd, RE (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM rudd@dave.nrl.navy.mil; pickett@dave.nrl.navy.mil OI Rudd, Robert/0000-0002-6632-2681 NR 56 TC 24 Z9 24 U1 1 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 1 PY 1998 VL 57 IS 1 BP 557 EP 574 DI 10.1103/PhysRevB.57.557 PG 18 WC Physics, Condensed Matter SC Physics GA YP839 UT WOS:000071320800088 ER PT J AU Hammond, RT Davis, J Bobb, L AF Hammond, RT Davis, J Bobb, L TI Equivalence regime for magnetohydrodynamic and lossy electromagnetic waves SO PHYSICAL REVIEW E LA English DT Article ID PERIOD MAGNETIC PULSATIONS; IONOSPHERE; MAGNETOSPHERE; EXCITATION; ATMOSPHERE; IONOSONDE AB It is shown that for particular combinations of conductivity and frequency, magnetohydrodynamic waves have the same properties as electromagnetic waves. These conditions prevail in the ionosphere for low frequency waves, so this result may be useful in calculating loss, reflection, and transmission coefficient for magnetohydrodynamic waves. C1 N Dakota State Univ, Dept Phys, Fargo, ND 58105 USA. USN, Air Warfare Ctr, Patuxent River, MD 20670 USA. RP Hammond, RT (reprint author), N Dakota State Univ, Dept Phys, Fargo, ND 58105 USA. EM rhammond@plains.nodak.edu NR 23 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 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JAN PY 1998 VL 57 IS 1 BP 1201 EP 1204 DI 10.1103/PhysRevE.57.1201 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA YT413 UT WOS:000071600400147 ER PT J AU Gavrishchaka, VV Ganguli, GI Bakshi, PM Koepke, ME AF Gavrishchaka, VV Ganguli, GI Bakshi, PM Koepke, ME TI Higher order nonlocal formalism for linear analysis of a magnetized multispecies plasma with inhomogeneous flows SO PHYSICS OF PLASMAS LA English DT Article ID ION-CYCLOTRON INSTABILITY; ELECTROSTATIC-WAVES; VELOCITY SHEAR; AURORAL ARC; FIELD; TURBULENCE; TOKAMAK; DRIFT AB The formalism necessary to study the collective properties of a plasma system with inhomogeneous flows is nonlocal and generally in the form of an integrodifferential equation. Usually the eigenvalue condition is reduced to a second-order differential equation for simplicity. While the gross physical behavior of the system can be obtained from the second-order differential equation level of description, higher-order corrections are necessary for greater accuracy. The limit in which the scale-size of the velocity inhomogeneity is large compared to the ion gyroradius is considered and a transverse flow profile sharply localized in space ("top-hat" profile) is assumed. In this limit, a simple analytical method for the solution of the general eigenvalue condition to all orders is developed. A comparison of the properties of the solutions obtained from the second-order differential equation level of description with those obtained from higher orders is presented. Both the resonant (dissipative) and the nonresonant (reactive) effects of velocity shear are considered, It is found that while the overall features are well represented by the second-order level of description, the higher-order corrections moderate the destabilizing effects due to velocity shear, which can be quite significant in some cases. (C) 1998 American Institute of Physics. C1 W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. USN, Res Lab, Washington, DC 20375 USA. Boston Coll, Dept Phys, Chestnut Hill, MA 02167 USA. RP Gavrishchaka, VV (reprint author), Sci Applicat Int Corp, Mclean, VA 22102 USA. EM gavrish@ppd.nrl.navy.mil NR 27 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 1998 VL 5 IS 1 BP 10 EP 21 DI 10.1063/1.872671 PG 12 WC Physics, Fluids & Plasmas SC Physics GA YR556 UT WOS:000071507100004 ER PT J AU Dahlburg, RB Boncinelli, P Einaudi, G AF Dahlburg, RB Boncinelli, P Einaudi, G TI The evolution of a plane jet in a neutral sheet SO PHYSICS OF PLASMAS LA English DT Article ID RESISTIVE TEARING INSTABILITY; HELIOSPHERIC CURRENT SHEET; EQUILIBRIUM SHEAR-FLOW; MAGNETIC-FIELD; SOLAR SURGES; VISCOSITY; PLASMA; MODE; TURBULENCE; TRANSITION AB The linear and nonlinear evolution of the plane magnetized jet, a magnetohydrodynamic configuration consisting of a plane fluid jet embedded in a neutral sheet, is examined. At low Alfven number (A = ratio of the characteristic Alfven speed to the characteristic flow speed), two ideally unstable modes are found that correspond to the sinuous and varicose modes of the fluid plane jet. Increasing A leads to a stabilization of both of these modes. For large A there is a separate resistively unstable mode. The ideal varicose mode and the resistive varicose mode are distinct modes with similar properties in a given range of A. A magnetohydrodynamic generalization of the Howard semicircle theorem indicates that a strong enough magnetic field will damp out all ideal modes. The stability properties of the two modes are studied in terms of their perturbation energy balances. The nonlinear evolution is quite different for the three modes in terms of time scales and of the properties and spatial location of the small-scale structures that strongly modify the initial configuration. The two ideal modes have in common the capability of accelerating the fluid initially at rest in a much more efficient way than the resistive one. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. Univ Florence, Dipartimento Energet Sergio Stecco, I-50100 Florence, Italy. Univ Pisa, Dipartimento Fis, I-56100 Pisa, Italy. RP Dahlburg, RB (reprint author), USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. RI Boncinelli, Paolo/C-2192-2013 NR 34 TC 31 Z9 31 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 1998 VL 5 IS 1 BP 79 EP 93 DI 10.1063/1.872677 PG 15 WC Physics, Fluids & Plasmas SC Physics GA YR556 UT WOS:000071507100011 ER PT J AU Dahlburg, RB AF Dahlburg, RB TI On the nonlinear mechanics of magnetohydrodynamic stability SO PHYSICS OF PLASMAS LA English DT Article ID SECONDARY INSTABILITY; RESISTIVE INSTABILITIES; FLOWING PLASMA; SOLAR SURGES; TURBULENCE; TRANSITION AB The nonlinear stability of magnetized plane Poiseuille flow, the magnetized plane jet, and the plane current-vortex sheet is examined. If it is assumed that the perturbation retains the form of the linearly unstable eigenmode, and that the most significant nonlinear effect is the distortion of the mean flow and magnetic field, then a Landau nonlinear stability equation can be derived from the streamwise-averaged perturbation energy balance. Secondary equilibrium velocity and magnetic fields are predicted. The possibility of subcritical instabilities also is discussed. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. RP Dahlburg, RB (reprint author), USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. NR 25 TC 20 Z9 20 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 1998 VL 5 IS 1 BP 133 EP 139 DI 10.1063/1.872682 PG 7 WC Physics, Fluids & Plasmas SC Physics GA YR556 UT WOS:000071507100017 ER PT S AU Agrawal, BN AF Agrawal, BN BE Kumar, V Agarwal, SK TI Microwave devices using smart sensors and actuators SO PHYSICS OF SEMICONDUCTOR DEVICES, VOLS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT IX International Workshop on the Physics of Semiconductor Devices (IWPSD) CY DEC 16-20, 1997 CL DELHI, INDIA SP Solid State Phys Lab, Jamia Millia Islamia, Indian Inst Technol, Delhi, Def Res & Dev Org, India, Dept Electr, India, Dept Sci & Technol, India, Council Sci & Ind Res, India, All India Council Tech Educat, India, Soc Photo Opt Instrumentat Engineers, US, Int Ctr Theoret Phys, Italy, Aixtron Semiconductor Technol GmbH, Germany, Harley Instruments, India, ASM Lithog, US, Rockwell Sci Ctr, US, SIMCO Sci Instruments Mkt Co P Ltd, India, Keithley Instruments, India, Semiconductor Complex Ltd, India AB This paper presents the analytical and experimental results on the application of piezoelectric sensors and actuators for the active shape control of microwave devices such as microwave antennas and filters. This approach can be used to provide dimensional stability for theses devices and also to change the shape of these devices as the performance requirements change such as beam shape of an antenna and frequency of a microwave filter. This research work examined the application of piezoelelctric actuators and sensors for the shape control of a beam, a common structural element for these devices. Experimental results show that the analytical model provides a reasonable prediction of actuator performance at low input voltage, but does not account for the nonlinear behavior of the piezoceramic and effects of hysteresis. C1 USN, Postgrad Sch, Spacecraft Res & Design Ctr, Monterey, CA 93943 USA. RP Agrawal, BN (reprint author), USN, Postgrad Sch, Spacecraft Res & Design Ctr, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2756-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3316 BP 849 EP 855 PG 7 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics; Physics, Condensed Matter SC Engineering; Materials Science; Optics; Physics GA BL03H UT WOS:000074086700161 ER PT J AU Purdy, AP George, CF AF Purdy, AP George, CF TI Crystal structures of the Ba-Cu(I) alkoxides Ba4Cu6(O)(OCEt3)(12) and BaCu6(OCEt3)(8) SO POLYHEDRON LA English DT Article DE heterometallic alkoxide; barium copper alkoxide; copper (I); oxide; oxo-alkoxide; disproportionation ID ALKALINE-EARTH; HETEROMETALLIC ALKOXIDES; BARIUM; COPPER(I); PRECURSORS AB A single crystal of the Ba-Cu(I) oxo-alkoxide Ba4Cu6(O)(OCEt3)(12) (1) was isolated from the reaction of Ba2Cu4(OCEt3)(8) (2) with oxygen. Oxo-alkoxide 1 crystallizes in the cubic space group 123 with the four Pa atoms distributed tetrahedrally around the central oxide ion and six Cu(OCEt3)(2)(-) units bridging each Pa atom to the three others. The Ba-Cu(I) alkoxides [BaCu(OCEt3)(3)](n) (3) and BaCu6(OCEt3)(8) (4) were also synthesized. Crystals were not obtained for 3, but the easily crystallized 4 has two Cu-3(OCEt3)(4)(-) moieties coordinated to a central Pa atom, and disproportionates in solution to many products. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Purdy, AP (reprint author), USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. NR 21 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0277-5387 J9 POLYHEDRON JI Polyhedron PY 1998 VL 17 IS 23-24 BP 4041 EP 4048 DI 10.1016/S0277-5387(98)00206-X PG 8 WC Chemistry, Inorganic & Nuclear; Crystallography SC Chemistry; Crystallography GA 148MR UT WOS:000077509600008 ER PT S AU Roberts, MJ Stenger-Smith, JD Zarras, P Lindsay, GA Hollins, RA Chafin, AP Yee, RY Wynne, KJ AF Roberts, MJ Stenger-Smith, JD Zarras, P Lindsay, GA Hollins, RA Chafin, AP Yee, RY Wynne, KJ BE Kippelen, B Bradley, DDC TI Alternating polyanion/polycation second order nonlinear optical films by aqueous solution deposition SO POLYMER PHOTONIC DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Polymer Photonic Devices CY JAN 28-30, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE organic thin films; active waveguide; alternating polyelectrolyte deposition AB Alternating polyelectrolyte deposition (APD) in aqueous solutions may be used to process nonlinear optical polymers (NLOPs) into noncentrosymmetric ordered films at ambient temperature. Second-order NLOP films were prepared by alternately dipping a substrate into aqueous solutions of a polycation and a polyanion. Polyepichlorohydrin substituted with stilbazolium side-chain chromophore was used as the cationic NLOP. The inactive polyanion was polystyrene sulfonate. Uniform layer to layer deposition is observed as evidenced by a linear increase of UV-Visible absorbance and quadratic increase of second harmonic generated light intensity as a function of film thickness. Films have been uniformly deposited up to 24 bilayers. Films have been further characterized by contact angle measurements, interferometry, and polarized light microscopy. Work is in progress to deposit thicker films of the same quality and to quantify NLO figures of merit. C1 USN, Air Weap Ctr, Weap Div,Mat & Chem Branch, China Lake, CA 93555 USA. RP Roberts, MJ (reprint author), USN, Air Weap Ctr, Weap Div,Mat & Chem Branch, Code 4B2200D,1 Adm Circle, China Lake, CA 93555 USA. NR 0 TC 6 Z9 6 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2720-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3281 BP 126 EP 131 DI 10.1117/12.305412 PG 6 WC Chemistry, Applied; Materials Science, Multidisciplinary; Optics; Physics, Applied; Polymer Science SC Chemistry; Materials Science; Optics; Physics; Polymer Science GA BL04K UT WOS:000074112300013 ER PT J AU Kwon, YW Liu, CT AF Kwon, YW Liu, CT TI Effects of non-uniform particle distributions on damage evolution in pre-cracked, particulate composite specimens SO POLYMERS & POLYMER COMPOSITES LA English DT Article ID BEHAVIOR; GROWTH AB Particle distribution in a particulate composite, in general, cannot be controlled so that a composite specimen can have a non-uniform particle distribution. This study examines the effects of non-uniform particle distributions in particulate composite specimens made of hard particles embedded in a soft rubbery binder on the crack tip behaviour, using a numerical technique called a micro/macro-approach. This technique coup les the micro-level and macro-level analyses. The micro-level analysis uses a three-dimensional unit-cell model and a continuum damage theory at the constituent material level (the particles and the binder) while the macro-level analysis utilizes the finite element method at the smeared composite specimen level. Both analyses are conducted in tandem as damage evolves in the specimens. The study investigates the damage evolution around the crack tip, the resulting stress variation near the crack tip, and the crack opening displacement for several specimens with different particle distributions. All the specimens have the same average particle volume fraction so that all of them have the same average effective elastic modulus. Every specimen has multiple zones, each of which has a uniform particle distribution. A crack is located in a single zone. The numerical results indicate a possible wide variation of crack tip behaviours, for example, with respect to fracture strength from specimen to specimen, depending on the state of particle volume distribution and the location of the crack. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. Phillips Lab, OL AC PL RKCP, Edwards AFB, CA 93524 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU RAPRA TECHNOLOGY LTD PI SHREWSBURY PA SHAWBURY, SHREWSBURY, SHROPS, ENGLAND SY4 4NR SN 0967-3911 J9 POLYM POLYM COMPOS JI Polym. Polym. Compos. PY 1998 VL 6 IS 6 BP 387 EP 397 PG 11 WC Materials Science, Characterization & Testing; Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 150XK UT WOS:000077691200003 ER PT S AU Zolper, JC AF Zolper, JC BE Pearton, SJ Shul, RJ Wolfgang, E Ren, F Tenconi, S TI Junction field effect transistors for high-temperature or high-power electronics SO POWER SEMICONDUCTOR MATERIALS AND DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Power Semiconductor Materials and Devices CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc AB Junction field effect transistors (JFETs) are attractive for high-temperature or high-power operation since they rely on a buried semiconductor junction, and not a metal semiconductor interface as in a metal semiconductor (MESFET) or heterojunction field effect transistor (HFET), for modulating the transistor channel. This is important since a metal/semiconductor interface often degrades at elevated temperatures, either due to the ambient temperature or to Joule heating at high current levels, while a buried semiconductor junction can withstand higher temperatures. In fact, for proper design, the JFET becomes limited by thermal carrier generation in the semiconductor and not metallurgical degradation of the gate electrode. In this talk an overview is given of JFET technology based on GaAs, SiC, and GaN. While impressive room temperature, high-frequency, results have been reported for GaAs JFET's with unit current gain cut-off frequencies up to 50 GHz, more work is needed to limit substrate conduction for optimum operation at 300 degrees C and above. For SiC JFETs, well behaved transistor operation has been maintained up to 600 degrees C, however, increased frequency performance is needed. More recently, a GaN JFET has also been demonstrated that is promising for similarly high temperature operation but is presently limited by buffer conduction. Future directions for each of these technologies, and potential extension to high power switching devices such as thyristors, will be presented at the conference. C1 Off Naval Res, Arlington, VA 22217 USA. RP Zolper, JC (reprint author), Off Naval Res, Arlington, VA 22217 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-388-6 J9 MATER RES SOC SYMP P PY 1998 VL 483 BP 83 EP 87 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BK73W UT WOS:000073286800010 ER PT S AU Yater, JE Shih, A Abrams, R AF Yater, JE Shih, A Abrams, R BE Pearton, SJ Shul, RJ Wolfgang, E Ren, F Tenconi, S TI Electronic properties of wide bandgap materials SO POWER SEMICONDUCTOR MATERIALS AND DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Power Semiconductor Materials and Devices CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc AB Secondary electron emission spectroscopy is used to investigate the generation and transport of impact-ionized electrons in wide bandgap material. Secondary electron yield and energy distribution measurements from C(100) and CVD diamond samples are analyzed to obtain information about the internal gain and electron energy distribution following impact ionization, as well as the effects of the transport process on the internal electron distribution. By studying the emission from surfaces having a negative electron affinity (NEA), the total transmitted intensity and the full energy spectrum of the internal electrons are revealed in the measurements. Energy spectra measured from the diamond samples contain a low-energy peak whose energy position and width are independent of incident beam energy. This suggests that the peak represents the electron distribution produced by impact-ionization events. A large percentage of the total emitted electrons lie within this peak, indicating that the impact-ionization process is very efficient at generating low-energy electrons. Very high yields are measured from both samples, establishing the presence of high internal gain and efficient electron transport in the material. From the linear slope of the yield curves, the escape depth of the low-energy electrons is deduced to be much larger than similar to 0.1 mu m in both diamond samples. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yater, JE (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-388-6 J9 MATER RES SOC SYMP P PY 1998 VL 483 BP 431 EP 436 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BK73W UT WOS:000073286800058 ER PT B AU Fung, SC Karafiath, G McCallum, D AF Fung, SC Karafiath, G McCallum, D BE Oosterveld, MCW Tan, SG TI US navy sealift hydrodynamic investigations SO PRACTICAL DESIGN OF SHIPS AND MOBILE UNITS SE DEVELOPMENTS IN MARINE TECHNOLOGY LA English DT Proceedings Paper CT 7th International Symposium on Practical Design of Ships and Mobile Units CY SEP 20-25, 1998 CL THE HAGUE, NETHERLANDS SP MARIN, Minist Econ Affairs Netherlands, Municipality The Hague, TNO AB The U.S. Mid-Term Sealift Ship was designed as part of an Advanced Technology Development Program focusing on advances in efficiency, producibility, and commercial utility. The ship is designed to perform as a commercially operated container vessel, with the proviso that during a national emergency it can be transformed into a Ro-Ro for military sealift in a very short period of time. The Naval Sea Systems Command (NAVSEA) and Naval Surface Warfare Center, Carderock Division (NSWC-CD) have worked as a team to design and test a series of low resistance hull forms, and bow and stem variants beginning in 1994. The baseline hull form of this study was derived from an ammunition ship (AE 36) design which has an outstanding resistance characteristic but was never built [1]. Other hydrodynamic innovations, such as producible skeg, extended-skeg, podded propulsion, pre-swirl and reaction fins, and split-rudders were explored. In addition to the conventional propulsors, contra-rotation and large-diameter/low tip clearance propellers were also designed and tested. The results from these R&D efforts were very encouraging; significant savings in power were found when compared to an already excellent baseline design. This paper discusses the design rationale and presents some significant test data. The design is presented to the U.S. shipbuilding industry as a prototype to be used in the 21st century. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. RP Fung, SC (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-82918-0 J9 DEV MAR TEC PY 1998 VL 11 BP 677 EP 690 PG 14 WC Engineering, Marine SC Engineering GA BM12C UT WOS:000077676000080 ER PT S AU Dahlburg, RB Karpen, JT Einaudi, G Boncinelli, P AF Dahlburg, RB Karpen, JT Einaudi, G Boncinelli, P GP EUROPEAN SPACE AGCY TI Acceleration of the slow solar wind SO PROCEEDINGS OF AN INTERNATIONAL MEETING ON SOLAR JETS AND CORONAL PLUMES SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT International Meeting on Solar Jets and Coronal Plumes CY FEB 23-26, 1998 CL UNIV ANTILLES GUYANE, GUADELOUPE SP European Space Agcy, Inst Astrophys Paris, CNRS, COSTEP HO UNIV ANTILLES GUYANE DE magnetized wakes; slow solar wind; computational magnetohydrodynamics AB We review our recent work on a model. for the acceleration of the slow component of the solar wind which also accounts for the evolving plasmoids observed by LASCO (Einaudi et al. 1998). We model the solar wind above a coronal streamer as a magnetized wake (a relative of the magnetized jet), a configuration with a basic magnetic field given by B-o(y) = tanh y (e) over cap(z), and a basic velocity field given by W-o(y) = 1 - sech y (e) over cap(z). The plane magnetized wake configuration can describe, 1. it can lead to the formation of traveling plasmoids; 2. it can produce high levels of turbulence; and 3. it can produce streamwise filamentation. Two ideal unstable modes are found which correspond to the sinuous and varicose modes of the fluid plane jet. An additional resistive mode is found, which leads to the existence of travelling plasmoids. The stability properties of the three modes are studied in terms of their energy balances. Nonlinearly we find that the transition to turbulence via three-dimensional secondary instabilities quenches any further acceleration, as well as leading to a destruction of plasmoids. C1 USN, Res Lab, LCP&FD, Washington, DC 20375 USA. RP Dahlburg, RB (reprint author), USN, Res Lab, LCP&FD, Washington, DC 20375 USA. RI Karpen, Judith/E-1484-2012; Boncinelli, Paolo/C-2192-2013 NR 0 TC 4 Z9 4 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-684-8 J9 ESA SP PUBL PY 1998 VL 421 BP 199 EP 205 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL38L UT WOS:000075339900023 ER PT S AU Klimchuk, JA AF Klimchuk, JA GP EUROPEAN SPACE AGCY TI Theory of spicules, jets, plumes, and other solar eruptions SO PROCEEDINGS OF AN INTERNATIONAL MEETING ON SOLAR JETS AND CORONAL PLUMES SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT International Meeting on Solar Jets and Coronal Plumes CY FEB 23-26, 1998 CL UNIV ANTILLES GUYANE, GUADELOUPE SP European Space Agcy, Inst Astrophys Paris, CNRS, COSTEP HO UNIV ANTILLES GUYANE DE sun; jets; magnetic fields AB The Sun exhibits a wide variety of eruptive phenomena, ranging from H alpha spicules to X-ray jets. In this paper, I review some of the theories and models that have been proposed to explain these fascinating events, and I suggest directions for future improvements. I also address the question of why hot, high-speed reconnection outflows are not commonly observed. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Klimchuk, JA (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7675JAK, Washington, DC 20375 USA. RI Klimchuk, James/D-1041-2012 OI Klimchuk, James/0000-0003-2255-0305 NR 0 TC 7 Z9 7 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-684-8 J9 ESA SP PUBL PY 1998 VL 421 BP 233 EP 237 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL38L UT WOS:000075339900027 ER PT B AU Ting, A Moore, CI Krushelnick, K Burris, HR Manka, C Fischer, R Baine, M Esarey, E Hubbard, RF Sprangle, P AF Ting, A Moore, CI Krushelnick, K Burris, HR Manka, C Fischer, R Baine, M Esarey, E Hubbard, RF Sprangle, P BE Comyn, M Craddock, MK Reiser, M Thomson, J TI Channeling and time evolution of laser wakes and electron acceleration in a self-modulated laser wakefield accelerator experiment SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res ID STIMULATED RAMAN BACKWARD; UNDERDENSE PLASMAS; FIELD ACCELERATION; THOMSON SCATTERING; TERAWATT LASER; INTENSE; PULSES; PROPAGATION; EXCITATION; GENERATION AB Large amplitude plasma wakefields produced by a high power laser pulse in an underdense plasma were studied in a self-modulated laser wakefield accelerator (SM-LWFA) experiment. A pump-probe coherent Thomson scattering (CTS) technique was used and the lifetime of the wakefield was measured to be less than 5 psec. A plasma channel was observed to form in the wake of the pump laser pulse. The trailing probe laser pulse was observed to be guided by this channel for about 20 Rayleigh lengths. High energy electrons (up to 30 MeV) have been measured using a magnetic spectrometer. Highly non-linear plasma waves were also detected using forward Raman scattering diagnostics and were observed to correlate with the electron signals. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Ting, A (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 45 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 611 EP 615 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582800193 ER PT B AU Esarey, E Hubbard, RE Leemans, WP Ting, A Sprangle, P AF Esarey, E Hubbard, RE Leemans, WP Ting, A Sprangle, P BE Comyn, M Craddock, MK Reiser, M Thomson, J TI Femtosecond electron bunches from colliding laser pulses in plasmas SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res ID WAKE-FIELD ACCELERATION; SELF-MODULATION; WAKEFIELD; SCATTERING; WAVES; PROPAGATION; EXCITATION; RAMAN AB An injector and accelerator is analyzed that uses three collinear laser pulses in a plasma: a pump pulse, which generates a large wakefield (greater than or equal to 20 GV/m), and two counterpropagating injection pulses. When the injection pulses collide, a slow phase velocity beat wave is generated that injects electrons into the fast wakefield for acceleration. Particle tracking simulations in I-D with injection pulse intensities near 10(17) W/cm(2) indicate the production of high energy electrons with bunch durations as short as 3 fs, energy spreads as small as 0.3%, and densities as high as 10(18) cm(-3). C1 USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. RP Esarey, E (reprint author), USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. NR 23 TC 1 Z9 1 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 630 EP 632 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582800198 ER PT B AU Uhm, HS Choi, EH Ko, JJ Shin, HM AF Uhm, HS Choi, EH Ko, JJ Shin, HM BE Comyn, M Craddock, MK Reiser, M Thomson, J TI Influence of ion channel on electron beam propagation SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res ID CURRENTS AB The electron beam propagation from a gas-filled diode is investigated. The beginning portion of the electron beam pulse creates an ion channel not only inside the diode but also the region beyond the anode, A theoretical model is developed for a space-charge limited current of a relativistic electron beam propagating through an ion channel. A simple analytical expression of the space-charge limited current is obtained within the context of a thin beam approximation, where the conducting tube radius is much larger than the beam radius. Beam current propagating through an ion channel is measured experimentally for a mildly relativistic electron beam. Whenever the ion density inside a diode is the same as the beam electron density, the diode is short-circuited. The ion channel density at the short-circuiting time is numerically calculated and is used to estimate the space-charge limited current. It is shown that experimental data agree well with analytical results predicted by the theoretical model. C1 USN, Ctr Surface Warfare, Bethesda, MD 20817 USA. RP Uhm, HS (reprint author), USN, Ctr Surface Warfare, Bethesda, MD 20817 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 1870 EP 1872 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582800601 ER PT B AU Uhm, HS AF Uhm, HS BE Comyn, M Craddock, MK Reiser, M Thomson, J TI Electron beam propagation with premodulated energy and current SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res ID CONSISTENT NONLINEAR-THEORY; PLASMA; ACCELERATORS AB This paper considers an electron beam whose energy and current are simultaneously premodulated at the injection point of a drift tube. A theoretical model is developed for the subsequent current and energy modulations which propagate downstream. A closed integrodifferential equation for the normalized beam current is obtained in terms of time and propagation distance. To make the nonlinear current modulation analytically tractable, a small signal theory is introduced into the modulation calculation. The current modulation in the linear regime is a linear combination of the forward and backward waves of the initial current and energy modulations. The downstream energy modulation is also expressed by a linear combination of the forward and backward waves of the initial current and energy modulations. It is shown that the initial energy modulation is a very effective means for downstream current modulation. Numerical data even for a large initial current and energy modulations agree reasonably well with analytical results predicted by the linear theory. C1 USN, Ctr Surface Warfare, Bethesda, MD 20817 USA. RP Uhm, HS (reprint author), USN, Ctr Surface Warfare, Bethesda, MD 20817 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 3147 EP 3149 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582801023 ER PT B AU Blank, M Danly, BG Levush, B Latham, PE AF Blank, M Danly, BG Levush, B Latham, PE BE Comyn, M Craddock, MK Reiser, M Thomson, J TI Experimental investigation of a W-band gyroklystron amplifier SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res ID 2ND-HARMONIC GYROKLYSTRON; PERFORMANCE; DESIGN AB A four cavity W-band gyroklystron amplifier experiment is currently underway at the Naval Research Laboratory. The gyroklystron has produced 67 kW peak output power and 28% efficiency in the TE011 mode with a 55 kV, 4.3 A annular electron beam. The full width half maximum (FWHM) bandwidth is greater than 460 MHz. Small signal and saturated gains of 36 dB and 29 dB, respectively, have been observed. The amplifier is zero drive stable and the limiting oscillation is the TE011 operating mode in the output cavity. Experimental results are in good agreement with theoretical predictions. C1 USN, Res Lab, Washington, DC 20375 USA. RP Blank, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 3150 EP 3152 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582801024 ER PT B AU Gold, SH Fliflet, AW Kinkead, AK Hafizi, B Nezhevenko, OA Yakovlev, VP Hirshfield, JL True, R Hansen, RJ AF Gold, SH Fliflet, AW Kinkead, AK Hafizi, B Nezhevenko, OA Yakovlev, VP Hirshfield, JL True, R Hansen, RJ BE Comyn, M Craddock, MK Reiser, M Thomson, J TI X-band magnicon amplifier for the next linear collider SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res AB The magnicon is a scanning-beam microwave amplifier that is being developed as a high power, highly efficient microwave source for use in powering the next generation of high gradient electron linear accelerators. In this paper, we present a progress report on a new thermionic magnicon experiment designed to produce more than 50 MW at 11.4 GHz, using a 210 A, 500 kV beam from an ultrahigh convergence thermionic electron gun driven by a rep-rated modulator. This new design has a predicted efficiency in excess of 60%. C1 USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. RP Gold, SH (reprint author), USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 3153 EP 3155 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582801025 ER PT B AU Choi, JJ McCurdy, AH Wood, F Kyser, RH Calame, J Danly, BG Levush, B Parker, RK AF Choi, JJ McCurdy, AH Wood, F Kyser, RH Calame, J Danly, BG Levush, B Parker, RK BE Comyn, M Craddock, MK Reiser, M Thomson, J TI High power 35GHz gyroklystron amplifiers SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res AB High power coherent radiation sources at 35GHz are attractive for high gradient, compact particle accelerators and next generation high resolution millimeter wave radar/communications. A multi-cavity gyroklystron amplifier is considered a promising candidate for high power millimeter wave generation. Experiments on two-cavity and three-cavity gyroklystron amplifiers are underway to demonstrate 140kW, 35GHz coherent radiation amplification. Initial experiments show an efficiency of 32%, a bandwidth of 0.4%, and a saturated gain of 22dB which corresponds to peak power of 130kW. Experimental results are moderately in agreement with large signal simulations. Calculations also show that a stagger tuned three cavity circuit increases the bandwidth to more than 0.7%. C1 USN, Res Lab, Washington, DC 20375 USA. RP Choi, JJ (reprint author), USN, Res Lab, Code 6840, Washington, DC 20375 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 3159 EP 3161 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582801027 ER PT B AU Nguyen, K Danly, B Levush, B Blank, M True, R Felch, K Borchard, P AF Nguyen, K Danly, B Levush, B Blank, M True, R Felch, K Borchard, P BE Comyn, M Craddock, MK Reiser, M Thomson, J TI Electron gun and collector design for 94-GHz gyro-amplifiers SO PROCEEDINGS OF THE 1997 PARTICLE ACCELERATOR CONFERENCE, VOLS 1-3: PLENARY AND SPECIAL SESSIONS ACCELERATORS AND STORAGE RINGS - BEAM DYNAMICS, INSTRUMENTATION, AND CONTROLS LA English DT Proceedings Paper CT 17th Particle Accelerator Conference CY MAY 12-16, 1997 CL VANCOUVER, CANADA SP Nuclear & Plasma Sci Soc, IEEE, Amer Phys Soc Div Phys Beams, US DOE, Natl Sci Fdn, Off Naval Res AB This paper presents the electrical design of the magnetron injection gun and collector for high average power TE01 gyro-amplifiers, Both the gun and collector are currently under construction. C1 USN, Res Lab, Washington, DC 20375 USA. RP Nguyen, K (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4376-X PY 1998 BP 3180 EP 3182 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BM71G UT WOS:000079582801034 ER PT S AU O'Brien, RT Iglesias, PA AF O'Brien, RT Iglesias, PA GP AMER AUTOMAT CONTROL COUNCIL TI Time-varying steering control for an autonomous highway vehicle SO PROCEEDINGS OF THE 1998 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference CY JUN 24-26, 1998 CL PHILADELPHIA, PA SP Amer Automat Control Council, AIAA, AIChE, ASCE, IEEE, ISA, SCS AB An automated steering controller design is presented for a fundamentally new driving maneuver. The task for the controller is to steer the vehicle through a series of lane change maneuvers while traveling at a time-varying speed. A linear, time-varying steering controller is synthesized using a design procedure based on the solution of a H-infinity, optimal control problem. This controller is compared to several time-invariant steering controllers and it is shown that the time-varying controller provides performance that a time-invariant controller can not. C1 USN Acad, Annapolis, MD 21402 USA. RP O'Brien, RT (reprint author), USN Acad, Annapolis, MD 21402 USA. RI Iglesias, Pablo/A-5202-2008 OI Iglesias, Pablo/0000-0002-0840-155X NR 0 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-4530-4 J9 P AMER CONTR CONF PY 1998 BP 26 EP 30 PG 5 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL45T UT WOS:000075568200007 ER PT S AU Hewer, G Kenney, C Laub, AJ AF Hewer, G Kenney, C Laub, AJ GP AMER AUTOMAT CONTROL COUNCIL TI Sensitivity of control computations SO PROCEEDINGS OF THE 1998 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference CY JUN 24-26, 1998 CL PHILADELPHIA, PA SP Amer Automat Control Council, AIAA, AIChE, ASCE, IEEE, ISA, SCS AB The work of Bob Bass and others on the sensitivity of dynamical systems in control inspired continuing research on the accuracy and condition of control computations. In the following we provide details on some of the matrix extensions of the performance bounds Bass developed using the qualitative theory of ordinary differential equations. The theory of these matrix: performance bounds has been matched with reliable numerical procedures for their computation. C1 USN, Air Warfare Ctr, China Lake, CA 93555 USA. RP Hewer, G (reprint author), USN, Air Warfare Ctr, China Lake, CA 93555 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-4530-4 J9 P AMER CONTR CONF PY 1998 BP 415 EP 418 PG 4 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL45T UT WOS:000075568200089 ER PT S AU Halberg, E Kaminer, I Pascoal, A AF Halberg, E Kaminer, I Pascoal, A GP AMER AUTOMAT CONTROL COUNCIL TI Development of the rapid flight test prototyping system for unmanned air vehicles SO PROCEEDINGS OF THE 1998 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference CY JUN 24-26, 1998 CL PHILADELPHIA, PA SP Amer Automat Control Council, AIAA, AIChE, ASCE, IEEE, ISA, SCS AB This paper describes the development of a rapid prototyping system for flight testing of guidance, navigation, and control algorithms for unmanned air vehicles. The system affords a small team the ability to take a new concept in guidance, navigation, and control from initial conception to flight test. In order to do this, a number of engineering problems had to be overcome addressing a gamut of issues including weight, power, portability, risk, electronic interference, vibration, manpower, etc. The main contribution of the paper is the proof of concept flight test demonstration of a new integrated guidance and control algorithm [1]. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Halberg, E (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. OI PASCOAL, ANTONIO /0000-0002-0657-6671 NR 0 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-4530-4 J9 P AMER CONTR CONF PY 1998 BP 699 EP 703 PG 5 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL45T UT WOS:000075568200149 ER PT S AU Hallberg, E Kaminer, I AF Hallberg, E Kaminer, I GP AMER AUTOMAT CONTROL COUNCIL TI Horizontal control effector sizing for high speed civil transport SO PROCEEDINGS OF THE 1998 AMERICAN CONTROL CONFERENCE, VOLS 1-6 SE PROCEEDINGS OF THE AMERICAN CONTROL CONFERENCE LA English DT Proceedings Paper CT American Control Conference CY JUN 24-26, 1998 CL PHILADELPHIA, PA SP Amer Automat Control Council, AIAA, AIChE, ASCE, IEEE, ISA, SCS AB This paper discusses the development of a. numerical tool that determines the dynamic horizontal control effector sizing criteria, for given High Speed Civil Transport dynamic model. This criteria includes computing the maximum cg travel for a range of control effector sizes and actuator motion constraints, while guaranteeing an existence of a feedback controller that will recover from a severe gust without exceeding actuator amplitude and rate limits and satisfy other dynamic requirements. The key idea is to formulate these constraints in terms of Linear Matrix Inequalities. This tool is termed the Tail Sizing Design Tool. In addition, the paper illustrates the application of the tool to measuring the effect of adding a second horizontal control surface in the form of a canard. The capability to measure the effect of simple, symmetric, flexible motion of the vehicle is also addressed. Based on numerical analysis of designs, conclusions are drawn on the relative effectiveness of the use of canards, the nse of static versus dynamic controllers, and on the inclusion of aeroelastic effects. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Hallberg, E (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1619 BN 0-7803-4530-4 J9 P AMER CONTR CONF PY 1998 BP 1635 EP 1639 PG 5 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL45T UT WOS:000075568200347 ER PT S AU Heide, DA Kang, GS AF Heide, DA Kang, GS GP IEEE TI Speech enhancement for bandlimited speech SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING, VOLS 1-6 SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 98) CY MAY 12-15, 1998 CL SEATTLE, WA SP IEEE Signal Proc Soc AB Throughout the history of telecommunication, speech has rarely been transmitted with its full analog bandwidth (0 to 8 kHz or more) due to limitations in channel bandwidth. This impaired legacy continues with tactical voice communication. The passband of a voice terminal is typically 0 to 4 kHz. Hence, high-frequency speech components (4 to 8 kHz) are removed prior to transmission. As a result, speech intelligibility suffers, particularly for low-data-rate vocoders. In this paper, we describe our speech-processing technique, which permits some of the upperband speech components to be translated into the passband of the vocoder. According to our test results, speech intelligibility is improved by as much as three to four points even for the recently developed and excellent Department of Defense-standard Mixed Excitation Linear Predictor (MELP) 2.4 kb/s vocoder. Note that speech intelligibility is improved without expanding the transmission bandwidth or compromising interoperability with others. C1 USN, Res Lab, Washington, DC 20375 USA. RP Heide, DA (reprint author), USN, Res Lab, Code 5555, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-4428-6 J9 INT CONF ACOUST SPEE PY 1998 BP 393 EP 396 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Acoustics; Computer Science; Engineering; Telecommunications GA BL16B UT WOS:000074520700099 ER PT S AU Kang, GS Moran, TM AF Kang, GS Moran, TM GP IEEE TI Speech enhancement in noise and within face mask (microphone array approach) SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING, VOLS 1-6 SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 98) CY MAY 12-15, 1998 CL SEATTLE, WA SP IEEE Signal Proc Soc AB In certain communication environments, digital speech transmission systems must work in severe acoustic environments where the noise levels exceeds 110 dB. In other environments, speakers must use an oxygen face mask. In both situations, the intelligibility of encoded speech falls below an acceptable level. We have developed a technique for improving speech quality in these situations. Previous speech improvement methods have focused on processing the corrupted signal after it has been induced by the microphone. These methods have not performed adequately. In our technique, speech anomalies are attenuated by a microphone array before speech and noise become mixed into a signal. Our microphone array prototype has shown excellent performance. In an example of speech taken aboard an E2C aircraft, this noise-canceling microphone array improved the speech-to-noise ratio by as much as 18 dB. When the same technique is used in a face mask, muffled speech was almost completely restored to high quality speech. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kang, GS (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-4428-6 J9 INT CONF ACOUST SPEE PY 1998 BP 1017 EP 1020 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Acoustics; Computer Science; Engineering; Telecommunications GA BL16B UT WOS:000074520700255 ER PT S AU Coleman, JO AF Coleman, JO GP IEEE TI Embedded FIR generalized eigenfilters using test inputs SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING, VOLS 1-6 SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 98) CY MAY 12-15, 1998 CL SEATTLE, WA SP IEEE Signal Proc Soc AB A systematic approach is proposed for the individual or joint design of FIR filters to meet specifications on either a single filter or an embedding system (possibly multirate). System power gains in response to particular input spectra are optimized using a generalized eigenvector method. Numerical integration is avoided through a time-domain formulation. Real or complex filters with linear or nonlinear phase or N-th band properties are easily handled. C1 USN, Res Lab, Washington, DC 20375 USA. RP Coleman, JO (reprint author), USN, Res Lab, Code 5341, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-4428-6 J9 INT CONF ACOUST SPEE PY 1998 BP 1313 EP 1316 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Acoustics; Computer Science; Engineering; Telecommunications GA BL16B UT WOS:000074520700329 ER PT S AU Harrison, BF Harrison, JL AF Harrison, BF Harrison, JL GP IEEE TI Robust matched-field processing in uncertain shallow-water environments using an L-p-norm estimator SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING, VOLS 1-6 SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 98) CY MAY 12-15, 1998 CL SEATTLE, WA SP IEEE Signal Proc Soc AB An optimal approach to matched-field source localiztion in the presence of environmental uncertainties is the maximum a posteriori (MAP) estimator. The MAP estimator can be interpreted as an exponentially-weighted average over environmental realizations. In practice, only a finite number of environmental realizations can be included in this average resulting in a suboptimal processor. In this paper, we propose an L-p-norm estimator as a robust alternative to MAP in the presence of finite environmental sampling. We also show, using wavenumber gradients, that accurate localization estimates can be obtained using environmental realizations besides the precise true. Simulation results from a shallow-water environment are presented to illustrate the performance improvement. C1 USN, Ctr Undersea Warfare, Newport, RI 02841 USA. RP Harrison, BF (reprint author), USN, Ctr Undersea Warfare, Newport, RI 02841 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-4428-6 J9 INT CONF ACOUST SPEE PY 1998 BP 2441 EP 2444 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Acoustics; Computer Science; Engineering; Telecommunications GA BL16B UT WOS:000074520700611 ER PT S AU MacLeod, RB AF MacLeod, RB GP IEEE TI Modeling of active reverberation by time delay estimation SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING, VOLS 1-6 SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 98) CY MAY 12-15, 1998 CL SEATTLE, WA SP IEEE Signal Proc Soc AB This paper explores the statistical properties of underwater reverberation present in active sonar systems. The interference to signal processing which results from reverberation can be extensive, and is particularly acute when the boundaries (surface, bottom) of the water column are nearby. Of particular interest are situations where there may be weak targets masked by reverberation dominating the returning signal. The reverberation will be represented as the output of a linear system with the transmitted signal as an input. The random nature of the reverberation will be accounted for by using random parameters in the linear model, the most important of which are those parameters impacting the spatial distribution of the reverberation. Time delay estimation will be used to analyze reverberant signals obtained from a sonar system operating in a shallow water environment. The statistics of the linear models obtained from these analyses will be computed and discussed. C1 Naval Undersea Warfare Ctr, Newport, RI 02841 USA. RP MacLeod, RB (reprint author), Naval Undersea Warfare Ctr, Newport, RI 02841 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-4428-6 J9 INT CONF ACOUST SPEE PY 1998 BP 2465 EP 2468 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Acoustics; Computer Science; Engineering; Telecommunications GA BL16B UT WOS:000074520700617 ER PT S AU Kirsteins, IP Mehta, SK Fay, J AF Kirsteins, IP Mehta, SK Fay, J GP IEEE TI Adaptive separation of unknown narrowband and broadband time series SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING, VOLS 1-6 SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 98) CY MAY 12-15, 1998 CL SEATTLE, WA SP IEEE Signal Proc Soc AB Motivated by Thomson's multiple taper spectral estimation technique, we derive a new, robust procedure for automatically separating time series data into its constituent narrowband and broadband time series components. The new procedure avoids the pitfalls of adaptive notch filters, PCI method, or other similar algorithms, of mistaking and filtering local spectral peaks of the broadband component as narrowband components by decomposing the data vector into local subbands by a bank of matrix filters. Then in piecewise fashion, the narrowband components are estimated and then filtered from each subband using the Principal Component Inverse (PCI) method. Finally, the filtered components are coherently recombined to obtain the narrowband and broadband time series estimates. Computer simulation results show that the new procedure works well and can have performance close to the clairvoyant Wiener filter. C1 USN, Undersea Warfare Ctr, Div Newport, Newport, RI 02841 USA. RP Kirsteins, IP (reprint author), USN, Undersea Warfare Ctr, Div Newport, Code 3124, Newport, RI 02841 USA. NR 0 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-4428-6 J9 INT CONF ACOUST SPEE PY 1998 BP 2525 EP 2528 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Acoustics; Computer Science; Engineering; Telecommunications GA BL16B UT WOS:000074520700632 ER PT S AU Ekstrom, CR Burt, EA AF Ekstrom, CR Burt, EA GP IEEE IEEE TI Atomic fountain development at USNO SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM SE PROCEEDINGS OF THE IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium CY MAY 27-29, 1998 CL PASADENA, CA SP IEEE, Ultrasonics Ferroelectr & Frequency Control Soc C1 USN Observ, Washington, DC 20392 USA. RP Ekstrom, CR (reprint author), USN Observ, Washington, DC 20392 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-4373-5 J9 P IEEE INT FREQ CONT PY 1998 BP 23 EP 27 DI 10.1109/FREQ.1998.717873 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BL72D UT WOS:000076440400006 ER PT S AU Dominguez, DD McGill, RA Chung, R Nguyen, V AF Dominguez, DD McGill, RA Chung, R Nguyen, V GP IEEE IEEE TI Performance of an embedded SAW sensor for filter bed monitor and the development of a wireless monitoring prototype system SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM SE PROCEEDINGS OF THE IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium CY MAY 27-29, 1998 CL PASADENA, CA SP IEEE, Ultrasonics Ferroelectr & Frequency Control Soc AB Methods of measuring the residual adsorption capacity of porous carbon gas fitters are virtually non-existent. The main objective of our work is to evaluate the performance of gas sensors that can be operated successfully when embedded in the carbon of a gas filter. This paper describes how polymer-coated SAW sensors have been utilized to monitor the progression of dimethyl methylphosphonate through a filter test bed filled with carbon adsorbent. Performance of the sensor and the breakthrough characteristics of the filter test bed are described. We also describe the design of a miniature, wireless, remotely-powered SAW sensor system. C1 USN, Res Lab, Washington, DC 20375 USA. RP Dominguez, DD (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-4373-5 J9 P IEEE INT FREQ CONT PY 1998 BP 602 EP 607 DI 10.1109/FREQ.1998.717962 PG 6 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BL72D UT WOS:000076440400094 ER PT S AU McGill, RA Mlsna, TE Mowery, R AF McGill, RA Mlsna, TE Mowery, R GP IEEE IEEE TI The design of functionalized silicone polymers for chemical sensor detection of nitroaromatic compounds SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM SE PROCEEDINGS OF THE IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium CY MAY 27-29, 1998 CL PASADENA, CA SP IEEE, Ultrasonics Ferroelectr & Frequency Control Soc AB A series of novel chemoselective polymers have been designed, synthesized, characterized, and evaluated as sensor coatings for the detection of polynitroaromatic compounds. These polymers have been evaluated as thin sorbent coatings on surface acoustic wave (SAW) devices for their vapor sorption and selectivity properties. The most promising materials tested, include siloxane polymers functionalized with acidic pendant groups that are complimentary in their solubility properties for nitroaromatic compounds. The most sensitive of the new polymers exhibit SAW sensor detection limits for nitrobenzene and 2,4-dinitrotoluene at 3 parts per billion (ppb) and 235 parts per trillion (ppt) respectively. Optimized polymers exhibit low water vapor sorption, and rapid signal kinetics for nitrobenzene, reaching 90% of signal response in 4 seconds. Studies with an in-situ infrared spectroscopy technique are used to determine the mechanism of interaction between nitroaromatic compounds and the chemoselective polymer. C1 USN, Res Lab, Washington, DC 20375 USA. RP McGill, RA (reprint author), USN, Res Lab, Code 6670, Washington, DC 20375 USA. NR 0 TC 2 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-4373-5 J9 P IEEE INT FREQ CONT PY 1998 BP 630 EP 633 DI 10.1109/FREQ.1998.717966 PG 4 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BL72D UT WOS:000076440400098 ER PT S AU Chung, R McGill, RA AF Chung, R McGill, RA GP IEEE IEEE TI Performance of a polymer coated SAW device under pulse excitation SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM SE PROCEEDINGS OF THE IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium CY MAY 27-29, 1998 CL PASADENA, CA SP IEEE, Ultrasonics Ferroelectr & Frequency Control Soc C1 USN, Res Lab, Washington, DC 20375 USA. RP Chung, R (reprint author), USN, Res Lab, Code 6670, Washington, DC 20375 USA. NR 0 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-4373-5 J9 P IEEE INT FREQ CONT PY 1998 BP 634 EP 638 DI 10.1109/FREQ.1998.717967 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BL72D UT WOS:000076440400099 ER PT S AU DiLella, D Shaffer, RE McGill, RA Chung, R AF DiLella, D Shaffer, RE McGill, RA Chung, R GP IEEE IEEE TI Algorithms for the real-time analysis of SAW chemical sensor array data SO PROCEEDINGS OF THE 1998 IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM SE PROCEEDINGS OF THE IEEE INTERNATIONAL FREQUENCY CONTROL SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Frequency Control Symposium CY MAY 27-29, 1998 CL PASADENA, CA SP IEEE, Ultrasonics Ferroelectr & Frequency Control Soc C1 USN, Res Lab, Washington, DC 20375 USA. RP DiLella, D (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Shaffer, Ronald/I-2134-2012 NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1075-6787 BN 0-7803-4373-5 J9 P IEEE INT FREQ CONT PY 1998 BP 639 EP 644 DI 10.1109/FREQ.1998.717968 PG 6 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BL72D UT WOS:000076440400100 ER PT S AU Roman, JE Nichols, LT Williams, KJ Esman, RD Tavik, GC Livingston, M Parent, MG AF Roman, JE Nichols, LT Williams, KJ Esman, RD Tavik, GC Livingston, M Parent, MG GP IEEE TI Photonic remoting of AN/SPQ-9B ADM ultra high dynamic range radar SO PROCEEDINGS OF THE 1998 IEEE RADAR CONFERENCE: RADARCON 98 SE Radar Conference LA English DT Proceedings Paper CT IEEE Radar Conference on Challenges in Radar Systems and Solutions CY MAY 11-14, 1998 CL DALLAS, TX SP IEEE, Aerosp & Electr Syst, IEEE, AESS, Dallas Sect AB We report initial demonstrations of photonic technology meeting the stringent phase noise and signal-to-noise ratio (SNR) requirements for remoting radars. In particular, fiber optic links were used to remote the antenna and transmitter of the Navy AN/SPQ-9B ADM radar. The remoting links tested successfully in transmit configuration without significantly degrading the 87 dB SNR of the radar. These results show the potential of photonic technology to remote other radars such as active arrays. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Roman, JE (reprint author), USN, Res Lab, Div Opt Sci, Code 5672, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4492-8 J9 RADAR CONF PY 1998 BP 15 EP 19 DI 10.1109/NRC.1998.677970 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL12P UT WOS:000074378700003 ER PT S AU Steiner, M Gerlach, K AF Steiner, M Gerlach, K GP IEEE TI Fast-converging maximum-likeihood interference cancellation SO PROCEEDINGS OF THE 1998 IEEE RADAR CONFERENCE: RADARCON 98 SE Radar Conference LA English DT Proceedings Paper CT IEEE Radar Conference on Challenges in Radar Systems and Solutions CY MAY 11-14, 1998 CL DALLAS, TX SP IEEE, Aerosp & Electr Syst, IEEE, AESS, Dallas Sect AB The use of adaptive linear techniques to solve signal processing problems is needed particularly when the environment external to the radar is not known a priori. Due to the lack of knowledge of the external environment, adaptive techniques require a certain amount of data to cancel the interference external to the radar or communication system. The amount of data required so that the performance of the adaptive processor is close (nominally within 3 dB) to the optimum is called the convergence time of the processor. The minimization of the convergence time is important since in many environments the external interference changes with time. Although there are heuristic techniques such as the loaded sample matrix inversion (LSMI) in the literature that provide fast convergence for particular problems, there is currently not a general solution for arbitrary interference that is derived via classical theory. In this paper, the authors derive a maximum-likelihood (ML) solution for a structured covariance matrix. The only structure assumed is that the thermal noise variance is known. Using this ML estimate, simulations show that the convergence is on the order of twice the number of narrow-band interference sources. C1 USN, Res Lab, Washington, DC 20375 USA. RP Steiner, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 7 Z9 9 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4492-8 J9 RADAR CONF PY 1998 BP 117 EP 122 DI 10.1109/NRC.1998.677987 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL12P UT WOS:000074378700020 ER PT S AU Lipps, R Kerr, D AF Lipps, R Kerr, D GP IEEE TI Polar reformatting for ISAR imaging SO PROCEEDINGS OF THE 1998 IEEE RADAR CONFERENCE: RADARCON 98 SE Radar Conference LA English DT Proceedings Paper CT IEEE Radar Conference on Challenges in Radar Systems and Solutions CY MAY 11-14, 1998 CL DALLAS, TX SP IEEE, Aerosp & Electr Syst, IEEE, AESS, Dallas Sect AB Polar reformatting is a technique that has been developed and used extensively in Spotlight SAR processing. The prerequisite for using this technique is to know the radar's aspect angle, with respect to the target, for each pulse received by this radar. The key to using this technique for ISAR is to know the target's rotational motion which in most cases is unknown. This paper will present a practical motion geometry for the rotational motion of a target, based on a parameterized model. A technique, based on this rotation model, to determine the rotation parameters, using measurements from the radar data itself, will be presented. A practical realization of this technique, using simplifications to the motion model, will be discussed and the effects of this simplification will be described. C1 USN, Res Lab, Washington, DC 20375 USA. RP Lipps, R (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 8 Z9 8 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4492-8 J9 RADAR CONF PY 1998 BP 275 EP 280 DI 10.1109/NRC.1998.678014 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL12P UT WOS:000074378700046 ER PT S AU Root, B AF Root, B GP IEEE TI HF radar ship detection through clutter cancellation SO PROCEEDINGS OF THE 1998 IEEE RADAR CONFERENCE: RADARCON 98 SE Radar Conference LA English DT Proceedings Paper CT IEEE Radar Conference on Challenges in Radar Systems and Solutions CY MAY 11-14, 1998 CL DALLAS, TX SP IEEE, Aerosp & Electr Syst, IEEE, AESS, Dallas Sect AB High-Frequency Over-the-Horizon (HF-OTH) radar uses ionospheric refraction to detect targets at thousands of kilometers. A timely surveillance of large areas requires relatively short dwells (coherent integration times) of less than 10 seconds. The resulting resolution in the Doppler Fourier transform is sufficient for detecting fast targets such as aircraft, but slow targets such as ships require integration times 12-30 seconds long to distinguish the ship peaks from the much more powerful ocean clutter. By modeling the first-order clutter as sinusoidal and subtracting it, we are able to expose ships in dwells as short as 3 seconds that would otherwise be masked by the mainlobe spread of the clutter. This technique is applied to data from the U.S. Navy's ROTHR. This approach is an alternative: to superresolution techniques and may sometimes be more robust. C1 USN, Res Lab, Washington, DC 20375 USA. RP Root, B (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 11 Z9 13 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4492-8 J9 RADAR CONF PY 1998 BP 281 EP 286 DI 10.1109/NRC.1998.678015 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL12P UT WOS:000074378700047 ER PT S AU Lin, CT Cantrell, BH AF Lin, CT Cantrell, BH GP IEEE TI Synthesizing a wideband waveform by using a phased array SO PROCEEDINGS OF THE 1998 IEEE RADAR CONFERENCE: RADARCON 98 SE Radar Conference LA English DT Proceedings Paper CT IEEE Radar Conference on Challenges in Radar Systems and Solutions CY MAY 11-14, 1998 CL DALLAS, TX SP IEEE, Aerosp & Electr Syst, IEEE, AESS, Dallas Sect AB A key parameter affecting the ability of many radars to perform target identification is down-range resolution. A large radar instantaneous bandwidth permits the use of high range resolution (HRR) and rotational imaging. However, a narrow bandwidth phased array radar cannot support wideband signals because the array is steered by phase shift rather than time delay. This paper characterizes the array limitations as a function of bandwidth and presents a new methodology for synthesizing a wideband waveform with the use of very few (3 or 4) pulses. The technique is based on forming an inverse filter to reduce the high sidelobes and eliminate the grating lobes that would be generated when combining only a few pulses. It is demonstrated that the achieved HRR results using multiple processed linear frequency modulated (LFM) signals through adaptive inverse filters are about as good as those derived from a single wideband pulse of the same resultant bandwidth. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. RP Lin, CT (reprint author), USN, Res Lab, Div Radar, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4492-8 J9 RADAR CONF PY 1998 BP 361 EP 366 DI 10.1109/NRC.1998.678028 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL12P UT WOS:000074378700060 ER PT S AU Hansen, JP Scheff, K AF Hansen, JP Scheff, K GP IEEE TI Ultrawideband sea clutter: System and measurements at X-band SO PROCEEDINGS OF THE 1998 IEEE RADAR CONFERENCE: RADARCON 98 SE Radar Conference LA English DT Proceedings Paper CT IEEE Radar Conference on Challenges in Radar Systems and Solutions CY MAY 11-14, 1998 CL DALLAS, TX SP IEEE, Aerosp & Electr Syst, IEEE, AESS, Dallas Sect AB This paper presents a system description, along with data examples, for an ultrawideband instrumentation radar which has recently been used by the Radar Division of the Naval Research Laboratory to measure low grazing angle sea clutter at X-band frequencies (3 cm wavelength).** The radar system employs a video impulse excited traveling wave tube (TWT), dual wideband horns and multiple head, digital sampling oscilloscope circuitry. In its highest resolution mode, the system utilizes sub-nanosecond transmit pulses (0.15 ns, 3 dB pulsewidth) at a 9 GHz center frequency to achieve resolutions as fine as 2 cm in the range dimension. Multiple resolution waveforms, combined with dual polarization, provide insights into the varied and dynamic character of the radar sea clutter. Upwind data examples, measured at a 4 degree grazing angle in 20 knot winds, are, examined. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. RP Hansen, JP (reprint author), USN, Res Lab, Div Radar, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4492-8 J9 RADAR CONF PY 1998 BP 393 EP 398 DI 10.1109/NRC.1998.678034 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL12P UT WOS:000074378700065 ER PT S AU Posner, FL AF Posner, FL GP IEEE TI Spiky sea clutter at low grazing angles and high range resolutions SO PROCEEDINGS OF THE 1998 IEEE RADAR CONFERENCE: RADARCON 98 SE Radar Conference LA English DT Proceedings Paper CT IEEE Radar Conference on Challenges in Radar Systems and Solutions CY MAY 11-14, 1998 CL DALLAS, TX SP IEEE, Aerosp & Electr Syst, IEEE, AESS, Dallas Sect AB X-band (9.5-10.0 GHz) back:scatter at near grazing incidence (0.2 deg) from the sea off the coast of Kauai, Hawaii was measured with a radar characterized by a high spatial resolution in range (0.3 m) and a high temporal resolution (2000 Hz PRE). Extensive amounts (over 1200 a per measurement) of vertically and horizontally polarized sea clutter data were taken for upwind and crosswind transmit geometries. Each type of data was analyzed over time scales varying from long (200 s), to intermediate (5 s), to short (50 ms), and over range swaths varying from full (160 m), to intermediate (30 m), to short (an individual range cell, 0.3 m). The different types of data each exhibited the spiky behavior which has come to be expected from sea backscatter observed at low grazing angles and high range resolutions, while showing, between themselves, marked transmit geometry and polarization dependent contrasts, with the horizontally polarized, upwind sea clutter being especially notable for its frequently occurring, significant high frequency spectral content. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. RP Posner, FL (reprint author), USN, Res Lab, Div Radar, Washington, DC 20375 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4492-8 J9 RADAR CONF PY 1998 BP 405 EP 410 DI 10.1109/NRC.1998.678036 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL12P UT WOS:000074378700067 ER PT B AU Bunce, JA AF Bunce, JA GP IEEE TI Results of the Naval Oceanographic Office's 1997 AUV workshop SO PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON UNDERWATER TECHNOLOGY LA English DT Proceedings Paper CT 1st International Symposium on Underwater Technology CY APR 15-17, 1998 CL TOKYO, JAPAN SP IEEE, Ocean Engn Soc, Inst Ind Sci, Univ Tokyo, USN, Off Naval Res, Asian Off AB The U.S. Navy has been developing Autonomous Underwater Vehicles (AUVs) for operational scenarios for many years. The maturity of this technology has reached a point where it is both feasible and economical to transition AUVs to the collection of environmental data for the Navy. With this in mind, the Naval Oceanographic Office (NAVOCEANO) has established an AUV program with the goal of matching different AUV capabilities to meet specific Navy requirements. During September 1997 NAVOCEANO worked with scientists from the Woods Hole Oceanographic Institution (WHOI), the Massachusetts institute of Technology (MIT), and the Florida Atlantic University(FAU). Operating onboard the Texas A&M research vessel GYRE, these scientific teams collected a wide variety of environmental data in Mississippi coastal waters. This paper compares the AUV technology and the data collected by these institutions with data collected by traditional hydrographic survey techniques, and concludes that each AUV has characteristics that provide excellent quality survey data. The differences in capabilities (size, weight, mission duration, etc.) point out that no vehicle can be expected to meet all survey requirements. The best solution is a suite of vehicles, using common processing techniques, targeted to specific operational scenarios. C1 USN, Oceanog Off, Stennis Space Ctr, MS 39522 USA. RP Bunce, JA (reprint author), USN, Oceanog Off, 1002 Balch Blvd, Stennis Space Ctr, MS 39522 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4273-9 PY 1998 BP 115 EP 120 DI 10.1109/UT.1998.670073 PG 6 WC Engineering, Marine SC Engineering GA BL12N UT WOS:000074378600021 ER PT S AU O'Brien, RT AF O'Brien, RT BE Obaidat, MS Davoli, F DeMarinis, D TI Time-varying H-infinity steering control SO PROCEEDINGS OF THE 1998 SUMMER COMPUTER SIMULATION CONFERENCE: SIMULATION AND MODELING TECHNOLOGY FOR THE TWENTY-FIRST CENTURY SE PROCEEDINGS OF THE SUMMER COMPUTER SIMULATION CONFERENCE LA English DT Proceedings Paper CT 1998 Summer Computer Simulation Conference on Simulation and Modeling Technology for the 21st-Century CY JUL 19-22, 1998 CL RENO, NV SP Soc Comp Simulat Int DE vehicle automation; H-infinity control; time-varying modeling ID SYSTEMS AB This paper addresses the design of a steering controller for an automated vehicle. A new class of tasks is considered where the vehicle is traveling at a known time-varying speed. Specifically, the task of the controller is to steer the vehicle through an accelerate & pass maneuver requiring the vehicle to move into an adjacent lane while accelerating, then return to the original lane while decelerating. The time-varying speed admits the use of a time-varying model of the vehicle's lateral dynamics. A steering controller is synthesized using H-infinity design procedure for linear, time-varying systems recently developed by the author. The procedure incorporates the performance objectives in the design using a generalized frequency domain technique. A series of simulation modules has been created to facilitate and standardize the design process. Results of numerical simulation are presented to illustrate the design process and the performance of the steering controller. C1 USN Acad, Annapolis, MD 21402 USA. RP O'Brien, RT (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0094-7474 BN 1-56555-149-4 J9 P SUMM COMP PY 1998 BP 179 EP 184 PG 6 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BM99N UT WOS:000080377000030 ER PT S AU Piper, GE Watkins, JM AF Piper, GE Watkins, JM BE Obaidat, MS Davoli, F DeMarinis, D TI System identification of the sound field in a fluid filled pipe SO PROCEEDINGS OF THE 1998 SUMMER COMPUTER SIMULATION CONFERENCE: SIMULATION AND MODELING TECHNOLOGY FOR THE TWENTY-FIRST CENTURY SE PROCEEDINGS OF THE SUMMER COMPUTER SIMULATION CONFERENCE LA English DT Proceedings Paper CT 1998 Summer Computer Simulation Conference on Simulation and Modeling Technology for the 21st-Century CY JUL 19-22, 1998 CL RENO, NV SP Soc Comp Simulat Int DE active noise control; modeling; system identification AB In this paper modeling of the sound field within a fluid filled pipe is investigated. One of the answers sought is the minimal model order for system identification that best captures the relevant characteristics of the acoustic path. In this study we develop a infinite order theoretical model of the sound field of an open-ended fluid filled pipe. The pole-zero configuration of this model is then analyzed to determine the minimal order model that accurately models the sound field. Finally, system identification schemes are performed on data generated by the theoretical model to produce IIR models. The results of the system identification models are compared to the theoretical model and the results are discussed. C1 USN Acad, Dept Weap & Syst Engn, Annapolis, MD 21402 USA. RP Piper, GE (reprint author), USN Acad, Dept Weap & Syst Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0094-7474 BN 1-56555-149-4 J9 P SUMM COMP PY 1998 BP 197 EP 201 PG 5 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BM99N UT WOS:000080377000033 ER PT S AU Piper, GE Dwan, TE Wick, CE Mitchell, EE AF Piper, GE Dwan, TE Wick, CE Mitchell, EE BE Obaidat, MS Davoli, F DeMarinis, D TI Environmental systems engineering course SO PROCEEDINGS OF THE 1998 SUMMER COMPUTER SIMULATION CONFERENCE: SIMULATION AND MODELING TECHNOLOGY FOR THE TWENTY-FIRST CENTURY SE PROCEEDINGS OF THE SUMMER COMPUTER SIMULATION CONFERENCE LA English DT Proceedings Paper CT 1998 Summer Computer Simulation Conference on Simulation and Modeling Technology for the 21st-Century CY JUL 19-22, 1998 CL RENO, NV SP Soc Comp Simulat Int DE environment; simulation; systems engineering; education AB A new course and track in the Systems Engineering major at the United States Naval Academy presents the design and analysis of environmental systems from a Systems Engineering approach. Several engineering topics and our approach to them are addressed in the course including: ecological dynamics, transport phenomena, meteorological, atmospheric and solar processes. The two particular areas of study in the new course to be discussed in this paper are: the analysis and simulation of thermal transport phenomenon and the simulation, measurement and analysis of ecological data. The Systems Engineer's role in the study of all of these environmental topics is emphasized throughout the course. C1 USN Acad, Dept Weapons & Syst Engn, Annapolis, MD 21402 USA. RP Piper, GE (reprint author), USN Acad, Dept Weapons & Syst Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0094-7474 BN 1-56555-149-4 J9 P SUMM COMP PY 1998 BP 449 EP 454 PG 6 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BM99N UT WOS:000080377000070 ER PT S AU Baran, RH Coughlin, JP AF Baran, RH Coughlin, JP BE Obaidat, MS Davoli, F DeMarinis, D TI Tactical renewal in a simulation-based self defense system SO PROCEEDINGS OF THE 1998 SUMMER COMPUTER SIMULATION CONFERENCE: SIMULATION AND MODELING TECHNOLOGY FOR THE TWENTY-FIRST CENTURY SE PROCEEDINGS OF THE SUMMER COMPUTER SIMULATION CONFERENCE LA English DT Proceedings Paper CT 1998 Summer Computer Simulation Conference on Simulation and Modeling Technology for the 21st-Century CY JUL 19-22, 1998 CL RENO, NV SP Soc Comp Simulat Int AB The production of effective tactics for combat control involves generating hypothetical alternatives and testing them in high-fidelity simulators to eliminate the ineffective candidates. The present objective is to assess the feasibility of embedding a faster-than-realtime simulator in a combat system for ship self defense in order to estimate survival probabilities attained by specified tactical plans. These estimated probabilities provide a basis for deciding whether to abandon the current plan in favor of a tactical renewal. Is it better to use a very high fidelity simulator, which is so slow that it can run only "a few" independent (Bernoulli) trials in the time allowed? -Or a less reliable simulator which can perform enough trials to effectively eliminate the possibility of sampling error? Assuming a "common sense" concept of operations, this paper describes Monte Carlo calculations the results of which clearly favor fidelity over speed unless the bias of the survival probability estimated by the faster simulator can be guaranteed not to exceed a few per cent. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. RP Baran, RH (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Code N12, Dahlgren, VA 22448 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0094-7474 BN 1-56555-149-4 J9 P SUMM COMP PY 1998 BP 594 EP 599 PG 6 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BM99N UT WOS:000080377000096 ER PT B AU Yun, X Hernandez, GC Bachmann, ER McGhee, RB Healey, AJ AF Yun, X Hernandez, GC Bachmann, ER McGhee, RB Healey, AJ GP IEEE IEEE IEEE TI An integrated GPS/INS Navigation System for Small AUVs using an asynchronous Kalman filter SO PROCEEDINGS OF THE 1998 WORKSHOP ON AUTONOMOUS UNDERWATER VEHICLES, (AUV '98) LA English DT Proceedings Paper CT 1998 Workshop on Autonomous Underwater Vehicles CY AUG 20-21, 1998 CL DRAPER LAB, CAMBRIDGE, MA SP IEEE Ocean Engn Soc HO DRAPER LAB DE INS; GPS; AUV; navigation; Kalman filter AB A Small AUV Navigation System (SANS) is being developed at the Naval Postgraduate School. The SANS is an integrated GPS/INS navigation system composed of low-cost, small-size components. It is designed to demonstrate the feasibility of using a four-cost Inertial Measurement Unit (IMU) to navigate between intermittent GPS fixes. This paper reports recent improvements to the SANS hardware, latest testing results after compensating heading-dependent derivations in the TCM-2 compass measurements, and development of an asynchronous Kalman filter for improved position estimation. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Yun, X (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 14 TC 2 Z9 3 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5190-8 PY 1998 BP 43 EP 49 DI 10.1109/AUV.1998.744438 PG 7 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic SC Acoustics; Engineering GA BM39S UT WOS:000078610000005 ER PT B AU Carpenter, RN AF Carpenter, RN GP IEEE IEEE IEEE TI Concurrent mapping and localization with FLS SO PROCEEDINGS OF THE 1998 WORKSHOP ON AUTONOMOUS UNDERWATER VEHICLES, (AUV '98) LA English DT Proceedings Paper CT 1998 Workshop on Autonomous Underwater Vehicles CY AUG 20-21, 1998 CL DRAPER LAB, CAMBRIDGE, MA SP IEEE Ocean Engn Soc HO DRAPER LAB AB The topic of concurrent mapping and localization (CML) using a forward look sonar (FLS) is addressed. In many AUV applications, artificial beacons are employed for long duration positioning, or Global Positioning System (GPS) data are used to provide navigation resets. There are numerous missions where these constraints are undesirable and it is the aim of CML to provide relative position by extracting information from the environment through which it is moving. A technique for CML using a multibeam FLS is presented. The method is based on forming objects based on compact regions of high-level bottom backscatter, extracting features from the objects to identify/label them to aid in the data association process, and using the objects in an extended Kalman filter (EKF). A simplified approach to the EKF is used, whereby a new and separate filter is initiated for each new object encountered. Vehicle position is then derived as a weighted sum of the outputs from the individual filters. This approach has been developed and tested using data collected with an advanced FLS referred to as the high resolution array (HRA). C1 USN, Undersea Warfare Ctr Div, Newport, RI 02841 USA. RP Carpenter, RN (reprint author), USN, Undersea Warfare Ctr Div, Newport, RI 02841 USA. NR 14 TC 9 Z9 9 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5190-8 PY 1998 BP 133 EP 148 DI 10.1109/AUV.1998.744449 PG 16 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic SC Acoustics; Engineering GA BM39S UT WOS:000078610000013 ER PT B AU Marr, WJ Healey, AJ AF Marr, WJ Healey, AJ GP IEEE IEEE IEEE TI Using the ST725 sonar for AUV feature based navigation and correction SO PROCEEDINGS OF THE 1998 WORKSHOP ON AUTONOMOUS UNDERWATER VEHICLES, (AUV '98) LA English DT Proceedings Paper CT 1998 Workshop on Autonomous Underwater Vehicles CY AUG 20-21, 1998 CL DRAPER LAB, CAMBRIDGE, MA SP IEEE Ocean Engn Soc HO DRAPER LAB AB This paper reports on a previous experimental investigation of the Tritech ST725 high resolution sonar system used onboard the NPS Phoenix and a possible extension of the results to an underwater feature based navigation and correction system. The ST725 sonar was used in progressively complex static environments to clearly image objects. Scanline analysis of the ST725 data was conducted and shown to be useful in extracting stationary target information on vertically oriented mine-like objects as well as a small sphere. Raw scanline processing using a "gating and thresholding" method was used to determine range, bearing, and approximate size/orientation. Additionally, by capturing the range of the first return, the sonar was shown to be capable of emulating a "profiling" sonar. Future synthesis of known underwater features with range and bearing information and scanline analysis may provide the underwater vehicle systems designer with an alternate method of navigation. The value of this topic in the advancement of understanding underwater technology is that actual experimental data were used and useful results were obtained. C1 USN Acad, Annapolis, MD 21402 USA. RP Marr, WJ (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 8 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5190-8 PY 1998 BP 149 EP 158 DI 10.1109/AUV.1998.744450 PG 10 WC Acoustics; Engineering, Marine; Engineering, Electrical & Electronic SC Acoustics; Engineering GA BM39S UT WOS:000078610000014 ER PT B AU Rumish, B Ingram, C White, R Joseph, D AF Rumish, B Ingram, C White, R Joseph, D GP IEEE IEEE TI Using GIS to aid in the search for underwater wrecks SO PROCEEDINGS OF THE 2000 INTERNATIONAL SYMPOSIUM ON UNDERWATER TECHNOLOGY LA English DT Proceedings Paper CT 2nd International Symposium on Underwater Technology CY MAY 23-26, 2000 CL TOKYO, JAPAN SP IEEE Ocean Engn Soc, Univ Tokyo, Inst Ind Sci, USN Off Res Int Field Off DE GIS; data analysis; search operations AB Large amounts of data of varying types are collected during shipwreck search operations. Several Geographic Information System (GIS) packages (including ArcInfo, ArcView, and their extensions) was used to quickly and efficiently view, overlay, query, analyze, and interpret these data during a search for wreckage from the Battle of Midway. Recently developed GIS software, ArcView Tracking and 3-D Analyst, were used during this survey to evaluate the potential of using GIS real-time and in a 3-D environment during underwater operations. In September 1999, ship time became available in conjunction with another survey to verify the backscatter imagery of the potentially man made objects found on a May 1999 survey. A high-resolution sonar towfish equipped with optical sensors was used. During the search operation, real-time navigation was displayed over data incorporated into the GIS from the May survey and newly acquired data, Using GIS increased the efficiency of the decision-making process, which was essential to ensure a successful short duration operation (less than 5 days). By using GIS in the decision-making process, all potential target sites were verified, A section of the superstructure of a ship and other shipwreck debris were found in one of the potential sites. The other sites were geological. C1 USN, Oceanog Off, Stennis Space Ctr, MS 39522 USA. RP Rumish, B (reprint author), USN, Oceanog Off, Code N9,1002 Balch Blvd,Bldg 9322, Stennis Space Ctr, MS 39522 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6378-7 PY 1998 BP 33 EP 36 PG 4 WC Engineering, Marine; Engineering, Civil SC Engineering GA BQ79V UT WOS:000089546000005 ER PT B AU Joseph, D White, R Bethge, T Palshook, J Ingram, C Rumish, B AF Joseph, D White, R Bethge, T Palshook, J Ingram, C Rumish, B GP IEEE IEEE TI Using the NAVOCEANO wide swath sidescan sonar Seamap-C to locate and differentiate man-made objects from natural features on the seafloor SO PROCEEDINGS OF THE 2000 INTERNATIONAL SYMPOSIUM ON UNDERWATER TECHNOLOGY LA English DT Proceedings Paper CT 2nd International Symposium on Underwater Technology CY MAY 23-26, 2000 CL TOKYO, JAPAN SP IEEE Ocean Engn Soc, Univ Tokyo, Inst Ind Sci, USN Off Res Int Field Off DE sidescan sonar; deep water target detection AB While testing new equipment and following a military survey, the Naval Oceanographic Office (NAVOCEANO) and Nauticos Corporation conducted a Seamap-C survey that delineated small regions of high reflectivity material in an abyssal plain northwest of Midway Atoll. The survey in the Midway area was based on a Nauticos Corporation RENAV(TM) analysis of the possible location of the Japanese carrier, Kaga, sunk during the Battle of Midway in June, 1942, Seamap-C imaged three potential targets for further investigation with the higher frequency EG & G 960 system. Upon closer examination with the higher frequency system, the secondary and tertiary targets were confirmed to be geologic in origin. Although the primary target proved to be geologic, it was flanked by scattered concentrations of small, sharp-edged objects with obvious shadows. Direct imaging (i.e. photos, video) is required to determine the provenance of these objects. A subsequent operation in the Midway area was conducted some months later using NAVOCEANO's Towed Oceanographic Survey System (TOSS) with higher resolution sidescan sonar (50/500 kHz), video cameras, and digital still photography. The optical survey identified a debris field, composed of twisted wreckage and the associated debris from one of the Japanese aircraft carriers sunk during the Battle of Midway. C1 USN, Ocenog Off, Stennis Space Ctr, MS 39522 USA. RP Joseph, D (reprint author), USN, Ocenog Off, Code N9,1002 Balch Blvd,Bldg 9322, Stennis Space Ctr, MS 39522 USA. NR 1 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6378-7 PY 1998 BP 37 EP 40 PG 4 WC Engineering, Marine; Engineering, Civil SC Engineering GA BQ79V UT WOS:000089546000006 ER PT B AU Bishop, GC AF Bishop, GC GP IEEE IEEE TI Gravitational field maps and navigational errors SO PROCEEDINGS OF THE 2000 INTERNATIONAL SYMPOSIUM ON UNDERWATER TECHNOLOGY LA English DT Proceedings Paper CT 2nd International Symposium on Underwater Technology CY MAY 23-26, 2000 CL TOKYO, JAPAN SP IEEE Ocean Engn Soc, Univ Tokyo, Inst Ind Sci, USN Off Res Int Field Off AB It has been proposed to use gravitational field maps to correct navigational errors inherent in some navigational systems presently in use on unmanned underwater vehicles (UUVs) and that such a technology might form the basis for a new UUV navigational system. However, the accuracy and usefulness of the navigational solution depends, among other things, on the accuracy of the gravitational field maps. Since gravitational fields are generally sparsely and irregularly sampled, mapping algorithms must be used to construct the field maps. To assess the impact of field maps computed from sparse sets of data on the accuracy of the navigational solution, the kriging algorithm is used to compute field maps with various grid spacings from both simulated and measured field data. Then position and bearing errors are simulated and the various field maps are used to obtain corrected navigational fixes. To assess the impact of the density of the field data on the accuracy of the navigational fix, the simulated data are sub-sampled and the process is repeated. Numerical results are shown that demonstrate some of the effects of grid spacing and data density on the accuracy of the navigational fix and that gravitational field maps may be used to provide a very accurate navigational fix. C1 USN, Undersea Warfare Ctr, Div Newport, Newport, RI 02840 USA. RP Bishop, GC (reprint author), USN, Undersea Warfare Ctr, Div Newport, 1176 Howell St, Newport, RI 02840 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6378-7 PY 1998 BP 149 EP 154 PG 4 WC Engineering, Marine; Engineering, Civil SC Engineering GA BQ79V UT WOS:000089546000025 ER PT B AU Schexnayder, KR Pettway, WC Sharp, KM AF Schexnayder, KR Pettway, WC Sharp, KM GP IEEE IEEE TI Results of the 1999 Naval Oceanographic Office AUV technology demonstration (AUV Fest '99) SO PROCEEDINGS OF THE 2000 INTERNATIONAL SYMPOSIUM ON UNDERWATER TECHNOLOGY LA English DT Proceedings Paper CT 2nd International Symposium on Underwater Technology CY MAY 23-26, 2000 CL TOKYO, JAPAN SP IEEE Ocean Engn Soc, Univ Tokyo, Inst Ind Sci, USN Off Res Int Field Off DE AUV; Fest; Navy; demonstration AB In November 1999, the Naval Oceanographic Office and the Naval Meteorology and Oceanography Command hosted the third annual AUV Fest in the Gulf of Mexico north of Ship Island, MS. The participants were several AUV research groups funded by the Office of Naval Research. The vehicles were from Florida Atlantic University, Lockheed-Perry Corp., Woods Hole Oceanographic Institution, the Naval Postgraduate School, end the Autonomous Undersea Systems Institute. The demonstrations consisted of a series of exercises and tasks designed to test the ability of these vehicles to collect military and scientific oceanographic data. These missions included near-shore rapid environmental assessment and mine detection. The results of these demonstrations are presented from the Navy viewpoint of using the AUV as a practical tool for data collection for operational support. C1 USN, Oceanog Off, Ocean Projects Div, Stennis Space Ctr, MS 39522 USA. RP Schexnayder, KR (reprint author), USN, Oceanog Off, Ocean Projects Div, Stennis Space Ctr, MS 39522 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6378-7 PY 1998 BP 231 EP 236 PG 4 WC Engineering, Marine; Engineering, Civil SC Engineering GA BQ79V UT WOS:000089546000039 ER PT S AU Kiriakidis, K AF Kiriakidis, K GP IEEE IEEE TI An LMI approach to the control of a class of nonlinear systems SO PROCEEDINGS OF THE 37TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-4 SE IEEE CONFERENCE ON DECISION AND CONTROL - PROCEEDINGS LA English DT Proceedings Paper CT 37th IEEE Conference on Decision and Control CY DEC 16-18, 1998 CL TAMPA, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci ID FUZZY CONTROL-SYSTEMS; OUTPUT PARAMETRIC MODELS; H-INFINITY CONTROL; NON-LINEAR SYSTEMS; STABILITY ANALYSIS; ROBUST STABILIZATION; IDENTIFICATION; DESIGN; ISSUES AB The paper considers the control of the class of nonlinear systems that can be represented by the convex hull of a collection of local linear approximates. Usage of such quasi-linear modeling reduces the problem of the robust stabilization of the class with static state or dynamic output feedback, against modeling error and parametric uncertainty, to a Linear Matrix Inequality (LMI) problem. C1 USN Acad, Dept Weapons & Syst Engn, Annapolis, MD 21402 USA. RP Kiriakidis, K (reprint author), USN Acad, Dept Weapons & Syst Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. NR 31 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0191-2216 BN 0-7803-4394-8 J9 IEEE DECIS CONTR P PY 1998 BP 1470 EP 1475 PG 6 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Operations Research & Management Science; Mathematics, Applied SC Automation & Control Systems; Computer Science; Engineering; Operations Research & Management Science; Mathematics GA BM76E UT WOS:000079708900290 ER PT S AU Bishop, BE Spong, MW AF Bishop, BE Spong, MW GP IEEE IEEE TI Control of redundant manipulators using logic-based switching SO PROCEEDINGS OF THE 37TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-4 SE IEEE Conference on Decision and Control LA English DT Proceedings Paper CT 37th IEEE Conference on Decision and Control CY DEC 16-18, 1998 CL TAMPA, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci AB In this paper we study the control of redundant planar robotic manipulators using a switched (or hybrid) control scheme, focusing on manipulators with a degree of redundancy of one. We emphasize the effectiveness of switched control systems with respect to stabilization and performance enhancement for this class of manipulators. We present a simulation study of logic-based switching control of a 3 DOF planar manipulator under end-effector trajectory tracking and demonstrate the capabilities of this scheme. C1 USN Acad, Annapolis, MD 21402 USA. RP USN Acad, 105 Maryland Ave, Annapolis, MD 21402 USA. EM bishop@novell.nadn.navy.mil; spong@decision.csl.uiuc.edu NR 13 TC 10 Z9 10 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1546 BN 0-7803-4394-8 J9 IEEE DECIS CONTR P PY 1998 BP 1488 EP 1493 PG 6 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Operations Research & Management Science; Mathematics, Applied SC Automation & Control Systems; Computer Science; Engineering; Operations Research & Management Science; Mathematics GA BM76E UT WOS:000079708900293 ER PT S AU Lynch, RS Willett, PK AF Lynch, RS Willett, PK GP IEEE IEEE TI Bayesian classification and the reduction of irrelevant features from training data SO PROCEEDINGS OF THE 37TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-4 SE IEEE CONFERENCE ON DECISION AND CONTROL - PROCEEDINGS LA English DT Proceedings Paper CT 37th IEEE Conference on Decision and Control CY DEC 16-18, 1998 CL TAMPA, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci AB In this paper, performance of a previously introduced method of data reduction (referred to as the Bayesian Data Reduction Algorithm) is demonstrated which uses a noninformative (i.e., Dirichlet distribution) prior on the symbol probabilities. The algorithm employs a "greedy" approach that relies on the average conditional probability of error as a metric for making data reducing decisions. Performance is compared to a neural network at classifying discrete feature vectors containing binary and ternary valued features, and it is shown that the Bayesian Data Reduction Algorithm is superior. However, performance of both schemes is also shown to degrade as the quantization fineness is increased with ternary valued features. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Lynch, RS (reprint author), USN, Undersea Warfare Ctr, Code 3124, Newport, RI 02841 USA. OI Willett, Peter/0000-0001-8443-5586 NR 1 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0191-2216 BN 0-7803-4394-8 J9 IEEE DECIS CONTR P PY 1998 BP 1591 EP 1592 PG 2 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Operations Research & Management Science; Mathematics, Applied SC Automation & Control Systems; Computer Science; Engineering; Operations Research & Management Science; Mathematics GA BM76E UT WOS:000079708900314 ER PT S AU O'Brien, RT Iglesias, PA AF O'Brien, RT Iglesias, PA GP IEEE IEEE TI Robust controller design for time-varying systems SO PROCEEDINGS OF THE 37TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-4 SE IEEE CONFERENCE ON DECISION AND CONTROL - PROCEEDINGS LA English DT Proceedings Paper CT 37th IEEE Conference on Decision and Control CY DEC 16-18, 1998 CL TAMPA, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci ID INFINITY AB This paper examines the design of feedback control systems for linear, time-varying systems. The design procedure is developed using a frequency domain description of a linear, time-varying system and the solution of the H-infinity, optimal control problem. In particular, design guidelines are derived for several basic performance and robustness objectives. These guidelines reflect the time dependence of the frequency response of a linear, time-varying system while retaining the frequency domain intuition of the time-invariant case. This procedure is analogous to the loop shaping design procedure of McFarlane and Glover for linear, time-invariant systems. C1 USN Acad, Annapolis, MD 21402 USA. RP O'Brien, RT (reprint author), USN Acad, Annapolis, MD 21402 USA. RI Iglesias, Pablo/A-5202-2008 OI Iglesias, Pablo/0000-0002-0840-155X NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0191-2216 BN 0-7803-4394-8 J9 IEEE DECIS CONTR P PY 1998 BP 3813 EP 3818 PG 6 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Operations Research & Management Science; Mathematics, Applied SC Automation & Control Systems; Computer Science; Engineering; Operations Research & Management Science; Mathematics GA BM76E UT WOS:000079708900739 ER PT S AU Watkins, JM Kiriakidis, K AF Watkins, JM Kiriakidis, K GP IEEE IEEE TI Adaptive control of time-varying systems based on parameter set estimation SO PROCEEDINGS OF THE 37TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-4 SE IEEE Conference on Decision and Control LA English DT Proceedings Paper CT 37th IEEE Conference on Decision and Control CY DEC 16-18, 1998 CL TAMPA, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci ID RECURSIVE LEAST-SQUARES; POLE-PLACEMENT; BOUNDED NOISE; IDENTIFICATION; EXCITATION; MODELS AB Adaptive control of time-varying plants, in the presence of unmodeled dynamics and bounded disturbances, via parameter set estimation is proposed. The set estimator uses normalization and maps the uniformly bounded equation error on parametric error, which characterizes the modeled part of the plant. Based on the information from the set estimator, a switching control criterion selects the parametric vector from a set of nominal model parameters and tunes in the adaptive controller. At the same time, through stabilization against the parametric error, the policy renders the closed-loop modeled dynamics robust with respect to the equation error mechanisms. C1 USN Acad, Dept Weap & Syst Engn, Annapolis, MD 21402 USA. RP USN Acad, Dept Weap & Syst Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. EM watkins@novell.nadn.navy.mil; kiriakid@novell.nadn.navy.mil NR 18 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0743-1546 BN 0-7803-4394-8 J9 IEEE DECIS CONTR P PY 1998 BP 4002 EP 4007 PG 6 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Operations Research & Management Science; Mathematics, Applied SC Automation & Control Systems; Computer Science; Engineering; Operations Research & Management Science; Mathematics GA BM76E UT WOS:000079708900774 ER PT S AU Khodary, AA Groves, GW AF Khodary, AA Groves, GW GP IEEE IEEE TI Use of passive side-mounted sensor to hit groundbased target from above SO PROCEEDINGS OF THE 37TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-4 SE IEEE CONFERENCE ON DECISION AND CONTROL - PROCEEDINGS LA English DT Proceedings Paper CT 37th IEEE Conference on Decision and Control CY DEC 16-18, 1998 CL TAMPA, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci AB Terminal guidance under the constraints that (i) the heading error must be greater than a specified angle (in order that the sensor see the target), and (ii) the magnitude of the lateral acceleration is limited, is studied. Only the kinematic features of flight are considered. In order to hit or come close to the target, the final segment of terminal flight must violate the heading-error constraint, during which time the target is invisible. If there is an additional condition (iii) that the missile must remain above the target (e.g., for imaging) during terminal descent, the optimum trajectory is a conic spiral. As in the previous case, there is a final segment of blind flight. The miss distance depends on the constraints and other parameters of the problem, as well as on the sensor measurement errors. Monte Carlo simulation was used to estimate the miss distance for the conic spiral case under various conditions. C1 USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Khodary, AA (reprint author), USN, Ctr Surface Warfare, 17230 Dahlgren Rd, Dahlgren, VA 22448 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0191-2216 BN 0-7803-4394-8 J9 IEEE DECIS CONTR P PY 1998 BP 4697 EP 4701 PG 5 WC Automation & Control Systems; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Operations Research & Management Science; Mathematics, Applied SC Automation & Control Systems; Computer Science; Engineering; Operations Research & Management Science; Mathematics GA BM76E UT WOS:000079708900926 ER PT B AU Chu, PC Fan, CW Hager, SD AF Chu, PC Fan, CW Hager, SD BE Chang, CP Chan, JCL Wang, JT TI Central South China Sea baroclinic eddies detected from an airborne expendable bathythermograph survey SO PROCEEDINGS OF THE 3RD INTERNATIONAL CONFERENCE ON EAST ASIA AND WESTERN PACIFIC METEOROLOGY AND CLIMATE LA English DT Proceedings Paper CT 3rd International Conference on East Asia and Western Pacific Meteorology and Climate CY MAY 16-18, 1996 CL CHUNGLI, TAIWAN AB An extensive airborne expendable bathythermograph (AXBT) survey of the South Chins Sea (SCS) was conducted during 14-25 h lay 1995 from a Naval Oceanographic Office RP-3 aircraft. Larger areas were sampled over a shorter period by the AXBT survey than by the conventional survey carried by ships. Three dimensional temperature field-obtained from the AXBT survey and the velocity field inverted from temperature (observed) and salinity (climatological) indicate the existence of warm-core-and cool;core eddies. The warm-core (cool-core) eddies are associating with upper layer anticyclones (cyclones). The warm-core-eddies extend to the depth of 300 m, which is the deepest level the AXBT can reach. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Chu, PC (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 981-02-3047-8 PY 1998 BP 364 EP 367 PG 4 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA BM06A UT WOS:000077489700050 ER PT S AU Purdy, B Rudoy, E McCormick, L Vega, E AF Purdy, B Rudoy, E McCormick, L Vega, E BE Danesy, D TI Negligible shock, high load, fast-acting hold down and release mechanism SO PROCEEDINGS OF THE 8TH EUROPEAN SPACE MECHANISMS AND TRIBOLOGY SYMPOSIUM SE ESA SPECIAL PUBLICATIONS LA English DT Meeting Abstract CT 8th European Space Mechanisms and Tribology Symposium CY SEP 29-OCT 01, 1999 CL TOULOUSE, FRANCE SP European Space Agcy, Ctr Natl Etudes Spatiales, Matra Marconi Space, Alcatel Space Ind C1 USN, Res Lab, Chatsworth, CA 91311 USA. RP Purdy, B (reprint author), USN, Res Lab, 9600 De Soto Ave, Chatsworth, CA 91311 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-752-6 J9 ESA SP PUBL PY 1998 VL 438 BP 311 EP 311 PG 1 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Engineering, Mechanical SC Engineering GA BN91J UT WOS:000083442500048 ER PT S AU Remmers, G Zueck, R Palo, P Taylor, R AF Remmers, G Zueck, R Palo, P Taylor, R BE Chung, JS Matsui, T Naito, S Sayed, M TI Mobile offshore base SO PROCEEDINGS OF THE EIGHTH INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL 1 SE International Offshore and Polar Engineering Conference Proceedings LA English DT Proceedings Paper CT 8th International Offshore and Polar Engineering Conference (ISOPE-98) CY MAY 24-29, 1998 CL MONTREAL, CANADA SP Int Soc Offshore & Polar Engineers DE megastructure; floating airfield; semisubmersible; platform; mobility; module connectors; logistics AB A Mobile Offshore Base (MOB) provides a forward-deployable logistics facility capable of conducting flight, maintenance, supply and other military support operations. A general set of mission requirements, driven by fixed wing cargo aircraft operations, results in MOB concepts around 1,500 m (5,000 ft) in length. Both the specialized functions and long length of a MOB platform make it unique compared to any floating structure ever built. This paper describes the research and development efforts underway along with alternative structural concepts currently under consideration to meet the technical challenges. C1 Off Naval Res, Arlington, VA 22217 USA. RP Remmers, G (reprint author), Off Naval Res, Arlington, VA 22217 USA. NR 0 TC 1 Z9 2 U1 0 U2 0 PU INTERNATIONAL SOCIETY OFFSHORE& POLAR ENGINEERS PI CUPERTINO PA PO BOX 189, CUPERTINO, CA 95015-0189 USA SN 1098-6189 BN 1-880653-35-4 J9 INT OFFSHORE POLAR E PY 1998 BP 1 EP 5 PG 5 WC Engineering, Marine; Engineering, Petroleum; Engineering, Geological SC Engineering GA BL50X UT WOS:000075722800001 ER PT S AU Zueck, RF Karnoski, S AF Zueck, RF Karnoski, S BE Chung, JS Matsui, T Naito, S Sayed, M TI Nonlinear response analysis of a towed seafloor plow SO PROCEEDINGS OF THE EIGHTH INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL 1 SE International Offshore and Polar Engineering Conference Proceedings LA English DT Proceedings Paper CT 8th International Offshore and Polar Engineering Conference (ISOPE-98) CY MAY 24-29, 1998 CL MONTREAL, CANADA SP Int Soc Offshore & Polar Engineers DE nonlinear; dynamic; analysis; cable; seafloor; plow AB Towing a plow along the seafloor is often the preferred method for burying cables, recovering seafloor minerals or measuring seafloor soil properties. This paper presents a nonlinear time-domain numerical model for simulating the global response of the seafloor plow as it traverses a seafloor with rapid changes in elevation. This model is useful for planning the course of the tow ship, determine changes in the length of the tow cable, and analyzing the efficiency of the plow operation. Even for highly erratic plowing maneuvers, the model exhibits a surprisingly high level of nonlinear solution robustness. C1 USN, Facil Engn Serv Ctr, Port Hueneme, CA 93041 USA. RP Zueck, RF (reprint author), USN, Facil Engn Serv Ctr, Port Hueneme, CA 93041 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INTERNATIONAL SOCIETY OFFSHORE& POLAR ENGINEERS PI CUPERTINO PA PO BOX 189, CUPERTINO, CA 95015-0189 USA SN 1098-6189 BN 1-880653-35-4 J9 INT OFFSHORE POLAR E PY 1998 BP 526 EP 530 PG 5 WC Engineering, Marine; Engineering, Petroleum; Engineering, Geological SC Engineering GA BL50X UT WOS:000075722800080 ER PT S AU Su, MY Burge, R Wesson, J Teague, W AF Su, MY Burge, R Wesson, J Teague, W BE Chung, JS Olagnon, M Kim, CH Koterayama, W TI A field experiment on breaking waves and bubble distribution in shallow water SO PROCEEDINGS OF THE EIGHTH INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL 3 SE International Offshore and Polar Engineering Conference Proceedings LA English DT Proceedings Paper CT 8th International Offshore and Polar Engineering Conference (ISOPE-98) CY MAY 24-29, 1998 CL MONTREAL, CANADA SP Int Soc Offshore & Polar Engineers DE bubbles; wave breaking; bubble density; void fraction AB Measurements of bubbles caused by wave breaking processes under various sea-state conditions were made by the Naval Research Laboratory during the Sandy Duck '97 Experiment at Duck, NC. Eight arrays consisting of void fraction meters, acoustic resonators, and thermistors were deployed in an area that ranged from inside the surf zone, within several hundred meters of the beach, to just outside the surf zone, about one-two kilometers offshore. The main measurements consisted of void fraction and bubble-size spectra. In addition, video images of the surf zone were made from a 140 ft tower located just off the beach, and acoustic power intensity was measured by a hydrophone located in the surf zone. These data are used to characterize wave-breaking frequency and intensity, and the distribution and size spectra of bubbles over depth under various wind and sea conditions. An overview of these measurements is given here. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Su, MY (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU INTERNATIONAL SOCIETY OFFSHORE& POLAR ENGINEERS PI CUPERTINO PA PO BOX 189, CUPERTINO, CA 95015-0189 USA SN 1098-6189 BN 1-880653-37-0 J9 INT OFFSHORE POLAR E PY 1998 BP 137 EP 143 PG 3 WC Engineering, Marine; Engineering, Petroleum; Engineering, Geological; Mechanics; Remote Sensing SC Engineering; Mechanics; Remote Sensing GA BL50Z UT WOS:000075723700022 ER PT S AU Wesson, JC Su, MY Burge, RE AF Wesson, JC Su, MY Burge, RE BE Chung, JS Olagnon, M Kim, CH Koterayama, W TI Some near shore breaking wave statistics outside the surf zone SO PROCEEDINGS OF THE EIGHTH INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL 3 SE International Offshore and Polar Engineering Conference Proceedings LA English DT Proceedings Paper CT 8th International Offshore and Polar Engineering Conference (ISOPE-98) CY MAY 24-29, 1998 CL MONTREAL, CANADA SP Int Soc Offshore & Polar Engineers DE oceanic bubbles; breaking waves; bubble density distribution AB Initial analysis of bubble density and distributions using 4 floating acoustic resonator arrays we deployed during the Sandy Duck '97 experiment are presented. Bubbles generated by a 15m/s wind at the beginning of a storm event penetrate to at least 3.6 m below the surface. The bubble spectra demonstrate the existence of a peak in the oceanic bubble density spectrum near r = 25 - 30 mu. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Wesson, JC (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INTERNATIONAL SOCIETY OFFSHORE& POLAR ENGINEERS PI CUPERTINO PA PO BOX 189, CUPERTINO, CA 95015-0189 USA SN 1098-6189 BN 1-880653-37-0 J9 INT OFFSHORE POLAR E PY 1998 BP 144 EP 151 PG 2 WC Engineering, Marine; Engineering, Petroleum; Engineering, Geological; Mechanics; Remote Sensing SC Engineering; Mechanics; Remote Sensing GA BL50Z UT WOS:000075723700023 ER PT B AU Trulove, PC De Long, HC AF Trulove, PC De Long, HC BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Investigation of the underpotential deposition of lead on gold in basic and acidic room-temperature chloroaluminate molten salts SO PROCEEDINGS OF THE ELEVENTH INTERNATIONAL SYMPOSIUM ON MOLTEN SALTS XI SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 11th International Symposium on Molten Salts at the 193rd Meeting of the Electrochemical-Society CY MAY 03-09, 1998 CL SAN DIEGO, CA SP Electrochem Soc, Phys Electrochem Div, Electrochem Soc, High Temp Mat Div, Electrochem Soc, Electrodeposit Div, USAF, Off Sci Res AB The underpotential deposition (UPD) of lead on polycrystalline gold was used to investigate the characteristics of the electrochemical quartz crystal microbalance (EQCM) in room-temperature chloroaluminate molten salts. The bulk and UPD reduction of lead on gold was observed in both acidic and basic molten salts. The mass of the lead UPD in both acidic and basic melts, as determined from both EQCM charge and frequency data, were essentially identical. These data indicate that the EQCM is well behaved in these systems. C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Trulove, PC (reprint author), USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-205-2 J9 ELEC SOC S PY 1998 VL 98 IS 11 BP 66 EP 77 PG 12 WC Chemistry, Multidisciplinary; Electrochemistry; Engineering, Chemical; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Engineering; Materials Science GA BL94E UT WOS:000077242400006 ER PT B AU Carlin, RT Cho, TH Fuller, J AF Carlin, RT Cho, TH Fuller, J BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Catalytic immobilized ionic liquid membranes SO PROCEEDINGS OF THE ELEVENTH INTERNATIONAL SYMPOSIUM ON MOLTEN SALTS XI SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 11th International Symposium on Molten Salts at the 193rd Meeting of the Electrochemical-Society CY MAY 03-09, 1998 CL SAN DIEGO, CA SP Electrochem Soc, Phys Electrochem Div, Electrochem Soc, High Temp Mat Div, Electrochem Soc, Electrodeposit Div, USAF, Off Sci Res AB Supported ionic liquid membranes (SILMs) were employed as membrane reactors to examine the oligomerization of ethene with and without the presence of a Ni(II) dimerization catalyst. The SILMs were prepared by imbibing either an 1.1:1.0 AlCl3:EMIC acidic melt or a 1.1:1.0:0.1 AlCl3:EMIC:MCl (MCl = LiCl, NaCl, or KCl) neutral buffered melt into a porous polyethersulfone support membranes. For SILMs without the Ni(II) catalyst, ethene oligomerization was promoted by the presence of protonic species in the neat melts, and hydrocarbon fractions from C-3 to C-6 were quantified in the product mixtures. The oligomerization activities decreased in the order acidic > LiCI buffered > NaCl buffered > KCI buffered. Importantly, the neutral buffered melts produced only saturated alkanes, while the acidic melt produced olefinic products. With the Ni(ll) homogeneous catalyst added, the acidic SILM produced primarily a butene fraction, while the NaCl neutral buffered SILM yielded ethane, C-3, and C-4 hydrocarbon fractions. C1 Off Naval Res, Arlington, VA 22217 USA. RP Carlin, RT (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 0 TC 10 Z9 10 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-205-2 J9 ELEC SOC S PY 1998 VL 98 IS 11 BP 180 EP 186 PG 7 WC Chemistry, Multidisciplinary; Electrochemistry; Engineering, Chemical; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Engineering; Materials Science GA BL94E UT WOS:000077242400016 ER PT B AU Cheek, GT Trulove, PC De Long, HC AF Cheek, GT Trulove, PC De Long, HC BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Electrochemical studies of tantalum and niobium in chloroaluminate solvent systems SO PROCEEDINGS OF THE ELEVENTH INTERNATIONAL SYMPOSIUM ON MOLTEN SALTS XI SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 11th International Symposium on Molten Salts at the 193rd Meeting of the Electrochemical-Society CY MAY 03-09, 1998 CL SAN DIEGO, CA SP Electrochem Soc, Phys Electrochem Div, Electrochem Soc, High Temp Mat Div, Electrochem Soc, Electrodeposit Div, USAF, Off Sci Res AB The electrochemical behavior of Nb4+ and Nb3+ in the aluminum chloride: 1-ethyl-3-methylimidazolium chloride molten salt system has been studied. Although Nb3+ is virtually insoluble in the acidic melt, Nb4+ is sufficiently soluble to allow study of its voltammetric characteristics. Electrochemical studies of TaCl5 in the aluminum chloride : acetonitrile solvent system have also been carried out, and the results shed some light on the various pathways available to Ta5+ reduction. C1 USN Acad, Annapolis, MD 21402 USA. RP Cheek, GT (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-205-2 J9 ELEC SOC S PY 1998 VL 98 IS 11 BP 205 EP 216 PG 12 WC Chemistry, Multidisciplinary; Electrochemistry; Engineering, Chemical; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Engineering; Materials Science GA BL94E UT WOS:000077242400019 ER PT B AU O'Grady, WE Clinton, DE Cheek, GT Trulove, PC De Long, HC AF O'Grady, WE Clinton, DE Cheek, GT Trulove, PC De Long, HC BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Structure of niobium and tantalum complexes in room-temperature chloroaluminate molten salts using XAFS SO PROCEEDINGS OF THE ELEVENTH INTERNATIONAL SYMPOSIUM ON MOLTEN SALTS XI SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 11th International Symposium on Molten Salts at the 193rd Meeting of the Electrochemical-Society CY MAY 03-09, 1998 CL SAN DIEGO, CA SP Electrochem Soc, Phys Electrochem Div, Electrochem Soc, High Temp Mat Div, Electrochem Soc, Electrodeposit Div, USAF, Off Sci Res AB Coordination numbers for Ta+5 and Nb+5 in the aluminum chloride : EMIC molten salt system have been derived from EXAFS data. The values are consistent with known melt properties, decreasing as the melt acidity increases and the number of chloride ligands decreases. The proposed structures also explain the potential shift observed as initially basic melts are made acidic. C1 USN, Res Lab, Washington, DC 20375 USA. RP O'Grady, WE (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-205-2 J9 ELEC SOC S PY 1998 VL 98 IS 11 BP 217 EP 226 PG 10 WC Chemistry, Multidisciplinary; Electrochemistry; Engineering, Chemical; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Engineering; Materials Science GA BL94E UT WOS:000077242400020 ER PT S AU Van Orden, KF Jung, TP Makeig, S AF Van Orden, KF Jung, TP Makeig, S GP HFES HFES HFES TI Eye activity correlates of fatigue during a visual tracking task SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID ALERTNESS; PERFORMANCE; SPECTRUM AB Five concurrent eye activity measures were used to model fatigue-related changes in performance during a visual compensatory tracking task. Five subjects demonstrated considerable variations in performance level within two 53-min testing sessions during which continuous video-based eye activity measures were obtained. For each subject, moving estimates of blink duration and frequency, fixation duration and frequency, and mean pupil diameter from one session were used to train an artificial neural network to produce moving estimates of changes in mean tracking performance during the same session. Applied to eye tracking data from a second session, the same networks produced moving estimates of tracking performance that were highly correlated with actual performance changes (R-2=0.65, range 0.30-0.89 across ten sessions). The results suggest that information from multiple eye measures may be combined to produce individualized and accurate estimates of sub-minute scale changes in alertness during continuous task performance. C1 USN, Hlth Res Ctr, San Diego, CA 92152 USA. RP Van Orden, KF (reprint author), USN, Hlth Res Ctr, San Diego, CA 92152 USA. NR 12 TC 2 Z9 2 U1 0 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1122 EP 1126 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900236 ER PT S AU Lilienthal, MG Smillie, RJ Bost, JR Dominguez, CO Kamhi, M Sheridan, TB Meister, D Wulfeck, WH AF Lilienthal, MG Smillie, RJ Bost, JR Dominguez, CO Kamhi, M Sheridan, TB Meister, D Wulfeck, WH GP HFES HFES HFES TI Can human factors technologies fill the gaps when there are fewer people to do the job? SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB In the government, as well as, other industries, economic pressures are forcing organizations to operate with less money. With an organization such as the military where advanced technologies for equipment capture a significant portion of available funds, the only alternative is to reduce personnel costs, i.e., can fewer people do the work without compromising operational capability. In addition to budget considerations, the problem becomes exacerbated when population trends are examined. The objective of this panel is to address personnel reduction by focusing on the U.S. Navy's stated goal of major cut-backs in crew size while maintaining the same level of operational capability and assessing the capability of available human factors technologies to support this shift. C1 USN, Operat N911B, Div Sci & Technol, Washington, DC USA. RP Lilienthal, MG (reprint author), USN, Operat N911B, Div Sci & Technol, 2000 Navy Pentagon, Washington, DC USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1195 EP 1199 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900248 ER PT S AU Oser, RL Gualtieri, JW Cannon-Bowers, JA AF Oser, RL Gualtieri, JW Cannon-Bowers, JA GP HFES HFES HFES TI Enhancing training systems design: Implementing an event-based approach SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB While human factors has become increasingly involved in many aspects of training systems design (e.g., displays, functional allocation), other aspects such as software architectures and databases, have not received the same level of involvement. These aspects are important because they provide the infrastructure by which the training environment is generated. Unfortunately, few frameworks exist to support the design of training infrastructures from a human factors perspective. One framework with potential application is the Event-Based Approach to Training (EBAT). EBAT has been empirically tested, and operationally demonstrated in numerous training environments. EBAT can guide the design of system infrastructures by highlighting linkages between all phases of training (e.g., exercise design, measurement, feedback). The purpose of this paper is to provide an overview of: (a) learning premises important for training system design, (b) the EBAT framework, (c) EBAT-derived design guidelines and engineering payoffs, and (d) future challenges for training systems design. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. RP Oser, RL (reprint author), USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. OI Cannon-Bowers, Janis/0000-0003-2154-4456 NR 13 TC 0 Z9 0 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1309 EP 1313 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900272 ER PT S AU Stout, RJ Salas, E Klein, G Cohen, M Orasanu, J Salas, E AF Stout, RJ Salas, E Klein, G Cohen, M Orasanu, J Salas, E GP HFES HFES HFES TI What do we know about training situational awareness? SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. RP Stout, RJ (reprint author), USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. NR 7 TC 1 Z9 1 U1 0 U2 2 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1371 EP 1373 PG 3 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900285 ER PT S AU Baker, DP Salas, E Cannon-Bowers, JA AF Baker, DP Salas, E Cannon-Bowers, JA GP HFES HFES HFES TI Team job analysis: A critical training need? SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB The purpose of this paper is to examine the issue of job analysis for teams (i.e., team job analysis) in light of its critical role in team training development. This was accomplished by: a) presenting a description of what constitutes a team job analysis and its critical requirements for team training development, b) summarizing characteristics of past approaches to team job analysis, c) analyzing the strengths and weaknesses of these approaches, and d) examining the applied and empirical research literature for guidance on how best to conduct a team job analysis. In addition, a series of thought provoking questions regarding team job analysis and its role in team training development are raised. C1 Univ Cent Florida, Orlando, FL 32816 USA. RP Baker, DP (reprint author), USN, Air Warfare Ctr, Training Syst Div, 12350 Res Pkwy, Orlando, FL 32816 USA. OI Cannon-Bowers, Janis/0000-0003-2154-4456 NR 21 TC 1 Z9 2 U1 0 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1408 EP 1411 PG 4 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900294 ER PT S AU Kass, SJ Ahlers, RH AF Kass, SJ Ahlers, RH GP HFES HFES HFES TI To VE or not to VE? A comparison of two VE technologies for training SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID KNOWLEDGE AB This paper summarizes the training value of two types of desk top virtual environment (VE) technologies. The advantages and disadvantages of a model-based and a digital image-based approach are described. The engine room spaces of a naval destroyer were modeled using each of these approaches to train Navy engineering students to conduct material readiness inspections. The impact of the technologies on dynamics, and the learning of systems knowledge and spatial orientation are discussed. This paper provides the practitioner with some issues and guidance to aid in deciding how to employ virtual environment technology for training. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. RP Kass, SJ (reprint author), USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1437 EP 1441 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900300 ER PT S AU Radtke, PH AF Radtke, PH GP HFES HFES HFES TI The application of virtual presence technology to team training SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB Knowledge about what to teach teams to improve team-related performance has increased. However, the techniques available to conduct team training are still relatively limited. The most common and most effective form of team training has been to provide teams with an opportunity to practice and receive feedback in realistic simulated team problems. Experience with these methods has increased awareness of the limitations associated with current team-training exercises. Specifically, the feedback provided tends to be over-generalized, and does not sufficiently involve the team members themselves in the process. One possible solution is the application of distributed training technologies that increases the ability of trainers and team members to share, inspect, analyze, and communicate during and after a team exercise. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. RP Radtke, PH (reprint author), USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1442 EP 1446 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900301 ER PT B AU Groutage, D AF Groutage, D GP IEEE, SIGNAL PROC SOC IEEE, SIGNAL PROC SOC TI The calculation of features for non-stationary signals from moments of the singular value decomposition of Cohen-Posch (positive time-frequency) distributions SO PROCEEDINGS OF THE IEEE-SP INTERNATIONAL SYMPOSIUM ON TIME-FREQUENCY AND TIME-SCALE ANALYSIS LA English DT Proceedings Paper CT IEEE-SP International Symposium on Time-Frequency and Time-Scale Analysis CY OCT 06-09, 1998 CL PITTSBURGH, PA SP IEEE, Signal Proc Soc AB This paper presents a new method for determining the principal features of a non-stationary time series process based on the singular value decomposition (SVD) of the Cohen-Posch positive time-frequency distribution. This new method uses density functions derived from the SVD singular vectors to generate moments that associate with the principal features of the non-stationary process. Since the SVD singular vectors are orthonormal, the vectors whose elements are composed of the squared-elements of the SVD vectors are discrete density functions. Moments generated from these density functions are the principal features of the nonstationary time series process. C1 USN, Ctr Surface Warfare, Puget Sound Detachment, Bremerton, WA 98314 USA. RP Groutage, D (reprint author), USN, Ctr Surface Warfare, Puget Sound Detachment, 530 Farragut Ave, Bremerton, WA 98314 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5073-1 PY 1998 BP 605 EP 608 DI 10.1109/TFSA.1998.721497 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL79B UT WOS:000076757100151 ER PT B AU Zolper, JC Pearton, SJ AF Zolper, JC Pearton, SJ BE Abernathy, CR Brown, WD Buckley, DN Dismukes, JP Kamp, M Moustakas, TD Pearton, SJ Ren, F TI Ion implantation in wide bandgap semiconductors: Device needs and technological challenges SO PROCEEDINGS OF THE SECOND SYMPOSIUM ON III-V NITRIDE MATERIALS AND PROCESSES SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd ECS Symposium on III-V Nitride Materials and Processes, at the 192nd Meeting of the Electrochemical-Society CY AUG 31-SEP 05, 1997 CL PARIS, FRANCE SP Electrochem Soc, European III V Nitride Community AB The wide bandgap semiconductors, SiC, III-Nitride, and to a lesser extent, diamond, are being developed for advanced electronic devices for operation at high-temperature or high-power. The renewed interest and device success In SiC and GaN-based electronic devices has largely been the result of improvements in the bulk (for SiC) or epitaxial material quality [1]. However, for many devices under development selective area doping is becoming a requirement. One example is shown in Fig 1c,d where selective doping of the source and drain regions of a AlGaN/GaN heterostructure field effect transistor (HFET) is employed to reduce the channel access resistance which can not be readily accomplished by a planar or recessed gate approach as done in other compound semiconductors. Figure 1c shows a structure with epitaxial regrown Ohmic regions while Fig. 1d shows a structure that employs selective area ion implanation in the Ohmic regions. Implantation will most likely be the preferred approach due to its high degree of manufacturability. C1 Off Naval Res, Arlington, VA 22217 USA. RP Zolper, JC (reprint author), Off Naval Res, Arlington, VA 22217 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-187-0 J9 ELEC SOC S PY 1998 VL 97 IS 34 BP 76 EP 82 PG 7 WC Electrochemistry; Materials Science, Coatings & Films; Physics, Condensed Matter SC Electrochemistry; Materials Science; Physics GA BK63L UT WOS:000072820400009 ER PT B AU Cheek, GT Trulove, PC Clinton, DE Hagans, PL O'Grady, WE DeLong, HC Mantz, RA AF Cheek, GT Trulove, PC Clinton, DE Hagans, PL O'Grady, WE DeLong, HC Mantz, RA BE Paunovic, M Datta, M Matlosc, M Osaka, T Talbot, JB TI Electrodeposition of tantalum and niobium from room-temperature chloroaluminate molten salt systems SO PROCEEDINGS OF THE SYMPOSIUM ON FUNDAMENTAL ASPECTS OF ELECTROCHEMICAL DEPOSITION AND DISSOLUTION INCLUDING MODELING SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Fundamental Aspects of Electrochemical Deposition and Dissolution Including Modeling at Electrochemical-Soc/International-Soc-of-Electrochemistry Meeting CY 1997 CL PARIS, FRANCE SP Electrochem Soc, Int Soc Electrochem AB The electrochemical reduction of NbCl5 and TaCl5 has been studied in the room-temperature aluminum chloride : 1-ethyl-3-methylimidazolium chloride molten salt system. In contrast to the rather simple behavior seen in the basic melt, reduction in the acidic melts occurs by a complex series of partially resolved steps. Under conditions in which Al2Cl7- is reduced (acidic melts), niobium and tantalum can be co-deposited with aluminum, although in relatively small amounts (<2% of Al). The effect of fluoride addition on niobium reduction has been briefly investigated. C1 USN Acad, Annapolis, MD 21402 USA. RP Cheek, GT (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 0 TC 2 Z9 2 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-180-3 J9 ELEC SOC S PY 1998 VL 97 IS 27 BP 204 EP 214 PG 11 WC Electrochemistry; Engineering, Chemical; Materials Science, Multidisciplinary SC Electrochemistry; Engineering; Materials Science GA BL49E UT WOS:000075695400020 ER PT B AU Clinton, DE Trulove, PC Hagans, PL De Long, HC AF Clinton, DE Trulove, PC Hagans, PL De Long, HC BE Paunovic, M Datta, M Matlosc, M Osaka, T Talbot, JB TI Electrodeposition and nucleation studies of chromium from an acidic ambient temperature chloroaluminate molten salt SO PROCEEDINGS OF THE SYMPOSIUM ON FUNDAMENTAL ASPECTS OF ELECTROCHEMICAL DEPOSITION AND DISSOLUTION INCLUDING MODELING SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Fundamental Aspects of Electrochemical Deposition and Dissolution Including Modeling at Electrochemical-Soc/International-Soc-of-Electrochemistry Meeting CY 1997 CL PARIS, FRANCE SP Electrochem Soc, Int Soc Electrochem AB The electrochemical reduction of chromium (II) in acidic AlCl3:EMIC (1-ethyl-3-methylimidazolium chloride) room temperature molten salt results in codeposition of aluminum and chromium. Two reduction peaks are observed in staircase cyclic voltammetry, with the first peak significantly smaller than the second. Constant potential deposition in the region of the first reduction peak results in the formation of of Al-Cr deposits consisting of 40 to 50 a/o Cr present as Cr(O) and Cr(II). Constant potential deposition in the region of second peak results in the formation of aluminum rich Al-Cr deposits. Evaluation of the chronoamperometric transient behavior during electrodeposition shows that the codeposit proceeds via a 3D diffusion controlled progressive nucleation on platinum and tungsten with different kinetic control. Gold, as a substrate, gives a decidedly sharper progressive nucleation mechanism which is under kinetic control. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Clinton, DE (reprint author), USN, Res Lab, Div Chem, Code 6170, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-180-3 J9 ELEC SOC S PY 1998 VL 97 IS 27 BP 215 EP 225 PG 11 WC Electrochemistry; Engineering, Chemical; Materials Science, Multidisciplinary SC Electrochemistry; Engineering; Materials Science GA BL49E UT WOS:000075695400021 ER PT B AU Shifler, DA Kruger, J Moran, PJ AF Shifler, DA Kruger, J Moran, PJ BE Natishan, PM Isaacs, HS JanikCzachor, M Macagno, VA Marcus, P Seo, M TI Passivity and breakdown of carbon steel in organic solvent mixtures of propylene carbonate and dimethoxyethane SO PROCEEDINGS OF THE SYMPOSIUM ON PASSIVITY AND ITS BREAKDOWN SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Passivity and its Breakdown at the 1st Joint International Meeting of the Electrochemical-Society/International-Society-of-Electrochemistry CY SEP 01-05, 1997 CL PARIS, FRANCE SP Electrochem Soc, Corros Div DE passivity; organic solutions; propylene carbonate; dimethoxyethane; DME; breakdown; electropolymerization; mechanisms; corrosion AB The passivity and breakdown of passivity of 1018 carbon steel in propylene carbonate (PC) and dimethoxyethane (DME) mixtures with 0.5 molar lithium hexafluoroarsenate supporting electrolyte was examined via several electrochemical and surface methods. Compatibility and the interrelationships of the passivating mechanisms found in pure PC (solvent adsorption, salt film formation) and DME (solvent adsorption, cation intermediate adsorption, electropolymerized film) solutions alone were identified in PC-DME/0.5M LiAsF6 mixtures ranging from 10 to 90 mole% PC. A discussion of these compatibilities and interrelationships is presented. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. RP Shifler, DA (reprint author), USN, Ctr Surface Warfare, Carderock Div, Code 613,9500 MacArthur Blvd, Bethesda, MD 20817 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-179-X J9 ELEC SOC S PY 1998 VL 97 IS 26 BP 432 EP 449 PG 4 WC Chemistry, Physical; Electrochemistry; Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Chemistry; Electrochemistry; Metallurgy & Metallurgical Engineering; Materials Science GA BL84D UT WOS:000076910000039 ER EF