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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

Imaging spectroscopy II; Proceedings of the Meeting, San Diego, CA, Aug. 20, 21, 1987

The conference presents papers on airborne imaging spectrometers, imaging spectrometry analysis, and spaceborne imaging spectrometers. Consideration is given to an imaging spectrometer for ocean and land remote sensing, an advanced solid-state array spectroradiometer, airborne visible/infrared imaging spectrometer design and performance, and a signal chain for the airborne visible/infrared imaging spectrometer. Other topics include imaging spectrometry as a tool for botanical mapping, the estimation of forest canopy characteristics and nitrogen cycling using lasing spectrometry, and a continuous readout photon counting imaging detector.

Vane, Gregg↗
NASA NTRS1988

Fiber optic and laser sensors V; Proceedings of the Meeting, San Diego, CA, Aug. 17-19, 1987

The papers contained in this volume focus on recent developments in fiber optic and laser sensors. Topics discussed include electric and magnetic field sensors, fiber optic pressure sensors, fiber optic gyros, fiber optic sensors for aerospace applications, fiber sensor multiplexing, temperature sensors, and specialized fiber optic sensors. Papers are presented on remote fiber optic sensors for angular orientation; fiber optic rotation sensor for space missions; adaptation of an electro-optic monitoring system to aerospace structures; optical fiber sensor for dust concentration measurements; and communication-sensing system using a single optical fiber.

De Paula, Ramon P.↗
NASA NTRS1988

Optoelectronic signal processing for phased-array antennas; Proceedings of the Meeting, Los Angeles, CA, Jan. 12, 13, 1988

Papers are presented on fiber optic links for airborne satellite applications, optoelectronic techniques for broadband switching, and GaAs circuits for a monolithic optical controller. Other topics include the optical processing of covariance matrices for adaptive processors, an optical linear heterodyne matrix-vector processor, and an EHF fiber optic-based array. An adaptive optical signal processing architecture using a signed-digit number system is considered along with microwave fiber optic links for phased arrays.

Bhasin, Kul B.↗
NASA NTRS1988

Airborne and spaceborne lasers for terrestrial geophysical sensing; Proceedings of the Meeting, Los Angeles, CA, Jan. 14, 15, 1988

The present conference on airborne and spaceborne remote sensing laser applications discusses topics in atmospheric and geophysical sciences-related sensors, lidar and DIAL component and subsystem technologies, and coherent laser experiments and semiconductor laser technologies. Attention is given to airborne lidar measurement of aerosols, a ground-based injection-locked pulsed TEA laser for wind measurements, chemical/biological agent standoff detection methods, lidars for wind shear erosion, laser tuning to selected gas absorption lines in the atmosphere, the NASA lidar-in-space technology experiment, and the Laser Atmospheric Wind Sounder.

Allario, Frank↗
NASA NTRS1988

Infrared systems and components II; Proceedings of the Meeting, Los Angeles, CA, Jan. 14, 15, 1988

The present conference on the development status of IR electrooptics technologies discusses topics concerning such systems' materials and architectures, their modeling and data processing requirements, and advancements in IR automatic target recognition. Attention is given to active multispectral three-dimensional vision sensor image evaluation, a VHSIC processor-based real-time image tracker, the use of Al-alloy castings as diamond machining substrates for optical surfaces, a two-dimensional recognition range model, calculations of the optical blurring in IR systems, synthetic IR scene generation, and automatic target recognition evaluation.

Liaw, H. M.↗
NASA NTRS1989

Critical currents of aligned grains of Tl-Ba-Ca-Cu-O compounds

A study of irreversibility in the magnetization curves of Tl2Ba2Ca2Cu3O10 and Tl2Ba2Ca1Cu2O8 was undertaken to determine the intragranular critical currents and the effects of flux-creep in grain-aligned samples of these materials. For fields of greater than 0.3 T, and H parallel to c axis, the critical supercurrent falls approximately exponentially with both magnetic field and temperature. Flux-creep is found to be linear in the logarithm of time at low fields over a wide temperature range.

Fang, M. M.↗
NASA NTRS1989

Preparation of 110K (Bi, Pb)-Sr-Ca-Cu-O superconductor from glass precursor

The Bi1.5Pb0.5Sr2Ca2Cu3O(x) glass, prepared by rapid quenching of the melt, showed T(sub g) of 383 C, crystallization temperature of approx. 446 C, melting temperature of approx. 855 C, and bulk density of 5.69 g/cu. cm. in air. The as-quenched glass was oxygen deficient. On heating in O2, it showed a slow, irreversible, and continuous weight gain starting at approx. 530 C. The influence of annealing conditions on the formation of various phases was investigated by XRD and electrical resistivity measurements. The 110K-T(sub c) phase did not form below 840 C. The amount of this phase increased with the sintering time at 840 C. A sample annealed at 840 C for 243 h in air and furnace cooled showed the highest T(sub c)(R=0) of 107.2K and transition width delta T(sub c)(10 to 90 percent) of approx. 2 K.

Bansal, Narottam P.↗
NASA NTRS1990

Microstructure and magnetization of doped Y-Ba-Ca-O materials prepared by melt quench and post annealing method

Y-Ba-Cu-O bulk materials prepared using the melt quench and post annealing method were shown to have very high maximum as well as remanent magnetization. Studies were carried out on materials prepared using this method which deviate from the Y:Ba:Cu = 1:2:3 stoichiometry. In one series of materials, only the stoichiometry was changed, in particular by introducing an excess of yttrium. In other cases, dopants including several rare earths were introduced. Effects of variations in composition on microstructure and phase evolution are discussed, as well as effects on the magnetic susceptibility and on the magnetization. The results show that doped materials can exhibit improvements in magnetic properties. Furthermore, the use of dopants sheds light on the role of defect sites in flux pinning.

Hojaji, H.↗
NASA NTRS1989

Cryogenic optical systems and instruments III; Proceedings of the Meeting, San Diego, CA, Aug. 17-19, 1988

Topics considered include the Space Infrared Telescope Facility (SIRTF) and superfluid helium on-orbit transfer (SHOOT), SIRTF cryogenic optics technology, and Cosmic Background Explorer scientific instruments, and the Advanced X-ray Astrophysics Facility (AXAF) cryogenic subsystem. Attention is also given to the Stratospheric Observatory for Infrared Astronomy (SOFIA), high-volume IR array testing and detector coolers, the development of IR detectors and associated electronics, and the Cryogenic Limb Array Etalon Spectrometer (CLAES).

Melugin, Ramsey K.↗
NASA NTRS1989

Synthesis and characterization of high-Tc superconductors in the Tl-Ca-Ba-Cu-O system

Both Tl2Ca2Ba2Cu3O10 and TlCa3BaCu3O8.5 are investigated for superconductivity as a function of the sintering temperature, time, atmosphere, and quench rate in an effort to synthesize the high-Tc superconducting phase in the thallium system. The samples are characterized by electrical resistivity measurements, X-ray diffraction, and scanning electron microscopy. Samples of starting composition Tl2Ca2Ba2Cu3O10 fired in air at 860-900 C and rapidly quenched show a Tc of 96-107 K. In contrast, specimens of starting composition TlCa3BaCu3O8.5 when baked at 900 C and slowly cooled in oxygen superconduct at 116 K and above and consist of Tl2Ca2Ba2Cu3O(10+x) as the dominant phase. The results also show that, in contrast to the case of YBa2Cu3O(7-x), doping with a small concentration of fluorine sharpens the resistive transition and produces a large Tc increase in thallium-based superconductors.

Bansal, Narottam P.↗
NASA NTRS1989

Laser applications in meteorology and earth and atmospheric remote sensing; Proceedings of the Meeting, Los Angeles, CA, Jan. 16-18, 1989

Various papers on laser applications in meteorology and earth and atmospheric remote sensing are presented. The individual topics addressed include: solid state lasers for the mid-IR region, tunable chromium lasers, GaInAsSb/AlGaAsSb injection lasers for remote sensing applications, development and design of an airborne autonomous wavemeter for laser tuning, fabrication of lightweight Si/SiC lidar mirrors, low-cost double heterostructure and quantum-well laser array development, nonlinear optical processes for the mid-IR region, simulated space-based Doppler lidar performance in regions of backscatter inhomogeneities, design of CO2 recombination catalysts for closed-cycle CO2 lasers, density measurements with combined Raman-Rayleigh lidar, geodynamics applications of spaceborne laser ranging, use of aircraft laser ranging data for forest mensuration, remote active spectrometer, multiwavelngth and triple CO2 lidars for trace gas detection, analysis of laser diagnostics in plumes, laser atmospheric wind sounder, compact Doppler lidar system using commercial off-the-shelf components, and preliminary design for a laser atmospheric wind sounder.

Sokoloski, Martin M.↗
NASA NTRS1989

Optical pattern recognition; Proceedings of the Meeting, Los Angeles, CA, Jan. 17, 18, 1989

Papers on optical pattern recognition are presented, covering topics such as the estimation of satellite pose and motion parameters using a neural net tracker, associative memory, optical implmentation of programmable neural networks, optoelectronic neural networks, dynamic autoassociative neural memory, heteroassociative memory, bilinear pattern recognition processors, optical processing of optical correlation plane data, and a synthetic discriminant function-based nonlinear optical correlator. Other topics include an interactive optical-digital image processor, geometric transformations for video compression and human teleoperator display, quasiconformal remapping for compensation of human visual field defects, hybrid vision for automated spacecraft landing, advanced symbolic and inference optical correlation filters, and a rotationally invariant holographic tracking system. Additional topics include the detection of rotational and scale-varying objects with a programmable joint transform correlator, a single spatial light modulator binary nonlinear optical correlator, optical joint transform correlation, linear phase coefficient composite filters, and binary phase-only filters.

Liu, Hua-Kuang↗
NASA NTRS1989

Image understanding and the man-machine interface II; Proceedings of the Meeting, Los Angeles, CA, Jan. 17, 18, 1989

Image understanding concepts and models, image understanding systems and applications, advanced digital processors and software tools, and advanced man-machine interfaces are among the topics discussed. Particular papers are presented on such topics as neural networks for computer vision, object-based segmentation and color recognition in multispectral images, the application of image algebra to image measurement and feature extraction, and the integration of modeling and graphics to create an infrared signal processing test bed.

Barrett, Eamon B.↗
NASA NTRS1989

Three-dimensional visualization and display technologies; Proceedings of the Meeting, Los Angeles, CA, Jan. 18-20, 1989

Special attention was given to problems of stereoscopic display devices, such as CAD for enhancement of the design process in visual arts, stereo-TV improvement of remote manipulator performance, a voice-controlled stereographic video camera system, and head-mounted displays and their low-cost design alternatives. Also discussed was a novel approach to chromostereoscopic microscopy, computer-generated barrier-strip autostereography and lenticular stereograms, and parallax barrier three-dimensional TV. Additional topics include processing and user interface isssues and visualization applications, including automated analysis and fliud flow topology, optical tomographic measusrements of mixing fluids, visualization of complex data, visualization environments, and visualization management systems.

Robbins, Woodrow E.↗
NASA NTRS1990

Spatial light modulators and applications III; Proceedings of the Meeting, San Diego, CA, Aug. 7, 8, 1989

Recent advances in the technology and applications of spatial light modulators (SLMs) are discussed in review essays by leading experts. Topics addressed include materials for SLMs, SLM devices and device technology, applications to optical data processing, and applications to artificial neural networks. Particular attention is given to nonlinear optical polymers, liquid crystals, magnetooptic SLMs, multiple-quantum-well SLMs, deformable-mirror SLMs, three-dimensional optical memories, applications of photorefractive devices to optical computing, photonic neurocomputers and learning machines, holographic associative memories, SLMs as parallel memories for optoelectronic neural networks, and coherent-optics implementations of neural-network models.

Efron, Uzi↗
NASA NTRS1989

X-ray/EUV optics for astronomy and microscopy; Proceedings of the Meeting, San Diego, CA, Aug. 7-11, 1989

Topics included in these proceedings are on X-ray/EUV zone plates, filters, and windows; X-ray/EUV microscopes, telescopes, and monochromators; the design, characterization, and test of multilayer optics; the fabrication of X-ray/EUV multilayer optics; and the design, characterization, and test of grazing incidence X-ray optics. Other topics are on the fabrication of grazing incidence X-ray optics, X-ray/EUV space observatories and missions, the test and calibration of X-ray/EUV instruments, X-ray polarimetry, and X-ray/EUV spectroscopy and instruments. Papers are presented on 8-keV X-ray zone plates, a cylindrical X-ray multilayer monochromator, multilayer mirrors for 182 A, advanced flow polishing of exotic optical materials, and optical analysis of grazing incidence ring resonators for free-electron lasers. Attention is also given to X-ray mirrors for the European Synchrotron Radiation Facility, the XUV wide-field camera for Rosat, an optical test and alignment method for the XMM mirror module, Bragg crystal polarimeters, and a liftoff process for multilayer phase gratings.

Hoover, Richard B.↗