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Rubin, B.

Publications and source records attributed to Rubin, B..

Occultation analysis of BATSE data: Operational aspects

The Burst and Transient Source Experiment (BATSE) large area detectors are being used to monitor hard x-ray/gamma ray sources on a daily basis for evidence of transient behavior. Flux measurements are performed using a simple earth occultation technique. Daily searches are also being performed to detect occultation steps of sources which are not being routinely monitored. Topics concerning the operational aspects of the occultation measurements are presented. Preliminary spectral results are also presented for several of the brighter sources.

Harmon, B. A.

Remote sensing technologies for Space Missions in the second half of the nineties' decade

The remote sensing research and technology to be used in the development of future NASA missions are discussed, with consideration given to earth sciences, planetary sciences, solar physics, and astrophysics. The remote sensing missions planned in the four application areas, their payload packages, and the particular instruments that will make up these packages are described. The advanced technologies to be used include systems and devices that address the detection of radiation in the radio, microwave, millimeter wave, submillimeter wave, IR, visible, UV, X-ray, and gamma-ray parts of the spectrum, including supporting technologies, such as optics, liquid cryogen transfer systems, and 'smart' sensors.

Sokoloski, M. M.

VHSIC processors for remote sensing

A generic data system is briefly described. Its possible application to EOS instrument requirements is considered in the light of a survey of the NASA mission set to be flown over the time span of roughly 1990 to 1995.

Benz, H. F.

Addressing the crush of sampling

An overall space information system involves sensing, processing, analyzing, and distributing space-acquired information. These systems may be partitioned into the spacecraft segment, the wideband space-to-ground communication segment, and the ground-based data analysis and distribution segment. The paper discusses NASA's advanced technology programs aimed at providing improved sensors and on-board data systems. Advances in charge-transfer devices, lasers, and microwave technologies will be responsible for major improvements in NASA's sensing and detection capabilities for future missions. These improvements will result in a future data crush that will amplify the data management problem.

Olstad, W. B.

Thermal IR imaging system using a self-scanned HgCdTe/CCD detector array

It is likely that future high resolution earth observation imaging systems will utilize self-scanned IR detectors. In an initial step toward this goal, an IR imaging system operating in the 10 to 12 micron spectral region has been developed. This system uses a 9-element HgCdTe/CCD linear array operating in the photoconductive mode, nine pre-amplifiers and a silicon CCD multiplexer integrated into a focal plane assembly. Opto-mechanical techniques are used to scan the scene and images are produced in real time. The imaging performance of this system is described and measurements of noise, responsivity, specific detectivity, and detector sensitivity profiles are presented. The requirements for more advanced detector arrays for use in future NASA remote sensing missions are also discussed.

Husain-Abidi, A. S.

A laser profilometer for digital terrain mapping

A preliminary design of a space-based decimeter accuracy ranging instrument is described along with the ranging subsystem, the pointing subsystem, and attitude reference. The measurement capabilities including ranging accuracy, the signal-to-noise ratio for water, ice, and solid Earth, footprint size, and atmospheric effects are defined and the overall system with its advantages and disadvantages are summarized.

Rubin, B.

Differential laser absorption monitoring of the atmosphere

In the airborne detection system of atmospheric constituents and pollutants described, double-ended differential absorption measurement is accomplished by rapidly current tuning the wavelength of a PbSSe diode laser across a single line of the species under consideration. As the laser wavelength sweeps periodically across the absorption line, the laser beam is amplitude modulated and is then synchronously detected. With this technique, a minimum detectable differential transmission of 0.02 percent is obtained for a 1-sec integration time.

Rubin, B.

Sensors and detectors in NASA's future missions

Advances in electronics are responsible for major improvements in NASA's sensing and detection capabilities for future space missions. Technologies such as charge-transfer devices, tunable diode lasers, millimeter and submillimeter wave solid-state receiver components, large-scale circuit integration, new electronic materials and processing techniques, and novel detector electronics are contributing to the goal of a tenfold increase in the capacity of data collection from future platforms and will be used for space exploration and utilization.

Rubin, B.

NASA's present and future sensor technology developments

NASA's overall sensing, data acquisition, and instrumentation programs are reviewed. The review shows that the trends in advanced sensor technology involve increased use of solid-state sensors, multiapplication sensors, standardized instrumentation, and miniaturized detectors. Examples are given of several new technologies, showing how improvements in sensor operational capability (such as enhanced sensitivity and spectral range) derived from these advances have resulted in relaxed spacecraft stability requirements, mission time savings, and savings in weight, size, and power. The introduction of multiapplication sensors and standardized instrumentation will result in measurement cost reduction and improved compatibility with standardized spacecraft.

Rubin, B.

New tooth enamel from brushite crystals

Appropriate nutrient gel solution could be used to precipitate brushite, which becomes hydroxyapatite, mineral found in bones and teeth. Gel can be made from sodium metasilicate and phosphoric acid, or gelatin, or other organic materials that polymerize in presence of acid to get gelantinous medium.

Rubin, B.

Growing single crystals in silica gel

Two types of chemical reactions for crystal growing are discussed. The first is a metathetical reaction to produce calcium tartrate tetrahydrate crystals, the second is a decomplexation reaction to produce cuprous chloride crystals.

Rubin, B.