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The split-geometry design for arrays of photoconductive HgCdTe infrared photodetectors described in the preceding article can also be used to mitigate the deleterious effect of a phenomenon called "sweepout," which degrades performance. Sweepout occurs in conventional small HgCdTe...

Focal-plane arrays of HgCdTe photoconductors have been designed and fabricated to satisfy special requirements for high-performance long-wavelength infrared (LWIR) photodetectors. The special requirements are the following:

A report describes a study of the relationships between (1) the viscosities and specific volumes of Ni/Zr melts and (2) the formability of Ni/Zr-alloy metallic glasses. Experiments were performed on electrostatically levitated, radiantly heated molten specimens of two compound-forming and...

A report describes experiments in which nonintrusive optical diagnostic techniques were applied to high-pressure fuel sprays in simulated advanced turbine-engine combustor environments. The experiments involved three different fuel injectors in two unique optically accessible combustors: a...

A computer program processes images acquired at different times by instrumentation aboard a spacecraft to detect small satellites of asteroids and other planetary bodies. The program coregisters the images, removes instrument artifacts and images of background stars, and performs a...

A report describes an investigation of the validity of using statistical methods based on single-point probability density functions (PDFs) in mathematical modeling of mixing between a turbulently flowing carrier gas and the vapor from liquid drops suspended in the gas. The...

The Automated Planning and Scheduling Environment (ASPEN) version 2 computer program comprises a modular, reconfigurable software framework and collection of software components that can be used for automated planning and scheduling in a variety of applications. ASPEN can automatically generate...

Three software products are being developed to help satisfy the needs of NASA and of private industry for reconfigurable active control systems to suppress vibrations in Reusable Launch Vehicles (RLVs) and other structures. These potentially highly marketable products are the following: The...

A library of computer programs has been developed to solve the problem of parametric ranking of a set of hypotheses on the basis of incomplete and/or uncertain information. In general, the ranking must be learned by use of training examples in which one observes the values of random...

A process for making superior diffusion platinum-aluminide bond coats for plasma-sprayed or physical-vapor-deposited thermal-barrier coats (TBCs) on superalloy substrates has been devised. The novel aspect of the process lies in the use of several relatively inexpensive pack diffusion steps to...