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A procedure has been devised for the use of steam to sterilize a water-purification cartridge, chrom- atographic column, or other closed packed column that is required to be kept filled with water and from which it is required to exclude air bubbles, which could impede flow. For the...

Electrostatic dust- collection systems that comprise wire grids connected to lightweight, low-power high-voltage sources have been invented for preventing the accumulation of dust on surfaces. Intended originally for use in keeping spacecraft solar panels free of dust, these systems could also be used on...

The Hazardous Gas Detection System 2000 (HGDS 2000) is the latest in a series of instrumentation systems for detecting gases leaking from a space shuttle on a launch pad. The HGDS is a fully redundant system that includes analog and digital electronic control circuitry and a sub- system for...

Research at Langley Research Center has developed a special fiber- Bragg grating optical filter for use in aircraft or spaceborne differential absorption lidar (DIAL) systems for measuring water vapor in the atmosphere of the Earth. The filter is an optical fiber containing two Bragg...

This report examines the simulation of eye move- ment and resulting stresses with mech- anical event simulation software to research retinal detachments, a condition that affects 25,000 people annually. The set-up of the bio- mechanical finite element model of the eye, as...

A report presents additional information on the devices described in “Noise-Reducing Slots in Quantum-Well Infrared Photodetectors” (NPO-20518), NASA Tech Briefs, Vol. 25, No. 6 (June 2001), page 6a. To recapitulate: it was proposed that incorporation of suitably dimensioned crossed...

An artificial-intelligence computer program generates and evaluates plans for spacecraft missions subject to constraints associated with spacecraft designs. The input to the program includes spacecraft design parameters (e.g., slew rates and battery capacities) and mission parameters (e.g.,...

Generalized Timelines API is a computer program that provides (1) a means of representing arbitrary realworld state and resource information for use in planning, scheduling, and plan- and schedule-executing software and (2) an application-programming interface (API) that accelerates the...

Failure-reporting devices somewhat similar to the “black box” data recorders on aircraft have been proposed. These devices were conceived for use on spacecraft, but might also be useful on terrestrial autonomous underwater vessels or terrestrial remote exploratory robots. The...

U-HUNTER (also called “UXOHUNTER”) is a computer program that affords knowledge-based real-time sensor- fusion and display capabilities for detecting buried objects and materials of interest. U-HUNTER is intended especially for inferring the presence of buried unexploded ordnance and...

Aircraft anti-icing systems of a proposed type would utilize static electric fields to reduce or eliminate the electrostatic forces that bond ice and water to metal surfaces. These would be lightweight, low-power-consumption, inexpensive systems that would be installed on the surfaces of...

A mathematical model of a quantum analog-computing device that would simulate the human decision-making process has been developed. Like the immune-inspired- computing model described in the preceding article, this model is intended to contribute to improvement in the autonomy of robots and spacecraft.

A report discusses three designs of proposed low-power, zero-vibration coolers for infrared instruments planned to be flown aboard spacecraft to perform astrophysical observations far from Earth. The designs take advantage of the radiative precooling available in the projected deep-space operational...

A report presents an experimental study of time-resolved, temperature-dependent photoluminescence in InxGa1–x As/GaAs specimens containing In0.6Ga0.4As quantum dots (QDs) distributed at several different areal densities on a GaAs surface and capped with GaAs. The specimens were fabricated by...

This paper presents a study of area production in mixing layers undergoing transition to turbulence. These layers evolve from the mixing of two initially segregated counterflowing streams under supercritical conditions. The study may contribute to development of means to control area...