An algorithm for filtering synthetic-aperture-radar (SAR) interferograms has been developed which substantially improves the performance of subsequent phase-unwrapping. It accomplishes this task by filtering the interferogram strongly in areas where the scene contains little detail, and weakly where the...

Electromagnetic particle-in-cell (EMPIC) codes provide a capability for numerically simulating the motions of electrically charged particles in electromagnetic fields, and hence have become standard software tools in plasma physics research. Most existing EMPIC codes are based on the use of...

The forward-link/simulator card (FLS) performs the fundamental satellite-telemetry data-transmission function for the forward (Earth-to-spacecraft) link in real time at rates up to 400 Mb/s. The FLS also simulates a Consultative Committee for Space Data Systems (CCSDS) telemetry data source that outputs data at rates...

A unique state-of-the-art process for exploiting hyperspectral satellite imagery, based on evolutionary computing methods, has been developed and a proof-of-concept demonstration has been conducted. This development is projected to lead to several important commercial products, including...

A report discusses alternative techniques for controlling the buoyancy, and thus the altitude and landings, of a balloon-borne instrumentation system that would be launched to explore the moon Titan of the planet Saturn. Some of the techniques are based on established concepts of heating or...

A report presents results of research on carbonate-based electrolytes to improve the low-temperature-performances of lithium-ion rechargeable electrochemical cells. The loss of performance with decreasing temperature is attributable largely to a decrease of ionic conductivity and the increase...

A novel set of primers has been developed for use in a polymerase chain reaction (PCR) to amplify the deoxyribonucleic acid (DNA) of cytomegalovirus (CMV). The purpose of this development is to enable faster, more sensitive detection of CMV virus infecting body fluids and tissues.

Since it was developed in the late 1980s, the Automated Fatigue Calculation Program (FATPLUS) has consistently demonstrated its ability to predict fatigue life, independently validate proprietary fatigue methodologies, identify fatigue-sensitive parts, and train engineers in predicting...

Two reports present further developments in the subject of "Computation of Characteristics of a Helical TWT Slow-Wave Circuit" (LEW-16571), NASA Tech Briefs, Vol. 22, No. 4 (April 1998), page 54. The subject is computation, by use of the MAFIA (Solution of MAxwell's Equations by the...

Pressure sensors that contain thin diaphragms made from the 6H polytype of silicon carbide (6H-SiC) have been developed. These are prototypes of pressure sensors for use at high temperatures in engines, power plants, material-processing systems, and numerous other applications.

Piezoelectric devices that would serve as spark plugs, power generators for spark plugs, and/or pressure sensors have been proposed for use in internal-combustion engines. Unlike conventional spark plugs, these devices would function without need for wire connections to external high-voltage sources....

The Job Standards Development System is a user-friendly expert system that (1) helps users select an appropriate work measurement methodology to develop job standards (or the less formal job time estimates) and (2) leads the users through the steps necessary to use a work time estimating technique to develop...