Multiple-quantum-well (MQW) AlxGa1-xAs/GaAs infrared photodetectors that are better suited [relative to prior AlxGa1-xAs/GaAs...

Briefs: Electronics & Computers
Airfield Wind Advisory Systems for General Aviation

An Airfield Wind Advisory System (AWAS) includes a self-contained weather station, located at an airfield, that measures speed and direction of the wind, the temperature, the barometric pressure, and the humidity. This ground station digitizes these measurements and transmits the measurement...

Briefs: Software
Computing Radiation Fluxes, Power, and Temperature for TOPEX

A computer program performs a unified analysis of the radiation exposure, the temperatures, and the power generation and distribution for predicting the performance of the TOPEX satellite on orbit and during maneuvers. The unified analysis is needed because all aspects are...

Briefs: Software
Program for Updating Parameters of Thermal Models

Parameter Identification in Thermal Networks (PITN) is a computer program developed to satisfy a need to update parameters in mathematical models of thermal systems in order to make the temperatures computed by the models equal to the temperatures measured in tests of the corresponding real...

Briefs: Software
Program Tracks Operation of a Remote Solid-State Recorder

Solid State Recorder Pointer Tracker (SSRPT) is a computer program developed specifically to aid ground-based monitoring and control of two redundant solid-state recorders (SSRs) aboard the Cassini Spacecraft. The SSRs store telemetry data until downlink times, which are limited to a...

Briefs: Software
Library for Developing Spacecraft-Mission-Planning Software

The Platform Independent Software Components for the Exploration of Space (PISCES) software library provides for web-based, collaborative development of computer programs for planning trajectories and other trajectory-related aspects of spacecraft-mission design. The PISCES...

A lightweight, collapsible hyperbaric chamber/airlock system has been proposed as a portable unit for treating decompression sickness. Copies of the system could be stowed compactly...

Briefs: Mechanical & Fluid Systems
Reconfigurable Exploratory Robotic Vehicles

A family of rugged, modular, reconfigurable, instrumented robotic vehicles has been proposed for use in exploration of the surfaces of Mars and other remote planets. These or similar vehicles could...

Electrokinetically enhanced bioremediation (EEB) is a method of engineered bioremediation of soil contaminated by such organic compounds as solvents and petroleum products. As depicted...

Briefs: Medical
Microgravity Tissue Engineering

A continuing program of research and development focuses on engineering of functional cartilage and cardiac muscle for scientific research and for eventual use in transplants. The program involves the use of cells, polymer scaffolds, and bioreactor vessels. A polymer scaffold serves as a three-dimensional...

An apparatus that includes a pulsed electron gun and a high-resolution ultraviolet spectrometer has been developed for use in (1) pulsed electron-impact excitation of transitions...

Infrared-sensor systems for real-time detection of accretion of ice on helicopter rotor blades are undergoing development. By providing early warnings of icing conditions, these...

Efforts are under way to develop back-surface-illuminated, thinned silicon charge-coupled devices (CCDs) with delta doping and integral optical filters to be used as image...

Briefs: Photonics/Optics
Capture and Escape of Charge Carriers in Quantum Dots

A report describes an experimental investigation of effects of thermally induced intermixing of In0.6Ga0.4As and GaAs on the dynamics of photoexcited charge carriers in In0.6Ga0.4As/GaAs quantum dots. The quantum dots (nanometer-size islands of...

Briefs: Photonics/Optics
Rayleigh-Scattering Measurements in Underexpanded Jets

A report describes experiments in which time-averaged and unsteady local variations in the densities of underexpanded supersonic free jets issuing from a choked circular nozzle were measured by laser-induced Rayleigh scattering. This study is part of a continuing effort to understand the...

Briefs: Photonics/Optics
Common-Path Heterodyne Interferometers

Common-path heterodyne interferometers (COPHIs) have been proposed for measuring small variations in the heights of surfaces. A COPHI could be used, for example, to measure the deviation of the surface...

Shared-aperture multiplexed holographic scanning telescopes have been proposed for use in lidar transceivers and other laser transmitters and receivers in remote sensing...

Two polarization-recycling techniques have been proposed to increase the efficiency of illumination of liquid-crystal display (LCD) panels. The motivation for this proposal lies in...

Filled skutterudites have shown promise as semiconducting materials with superior thermoelectric properties at temperatures up to at least 650 °C. This finding is a breakthrough in a...

The term "optical nose" refers to a fiber-optic chemical sensor of a type that has been proposed to enable distributed measurement of the concentrations of...

A compact, low-power device measures pressure via the pressure-induced damping of oscillation of a small mechanical resonator. To achieve compactness and low mass — and thus...

Briefs: Electronics & Computers
Integrated Capacitive Wheel-Contact Sensors

A low-power capacitive proximity sensor has been developed as a prototype of wheel-contact sensors for a small robotic vehicle. The sensor is integrated into a wheel and consists of only a few...

Briefs: Physical Sciences
Rare-Earth Optical Temperature Sensors

A recently developed type of fiber-optic temperature sensor utilizes narrow-band near-infrared radiation emitted by rare-earth ions. These sensors are suitable for use in harsh environments at...

Briefs: Physical Sciences
Capacitive Sensor for Measuring Level of Liquid Nitrogen

The feasibility of a capacitive sensor for measuring the level of liquid nitrogen in a container has been demonstrated. The basic sensor design could also readily be adapted to measurement of the levels of cryogenic liquids other than nitrogen.

Briefs: Electronics & Computers
Black Jack GPS Receiver

The Black Jack (BJ) receiver is the revolutionary flight Global Positioning System (GPS) receiver developed by NASA to fill future needs for orbit-based GPS science. These range from a receiver to determine precise (1-cm radial accuracy goal for JASON-1) orbits, to missions using the GPS signals for remote sensing of the...

Microelectromechanical sensors based on magnetoresistance have been proposed. Like other microelectromechanical sensors, these would be used to measure physical quantities that can be...

Digitally programmable analog membership-function circuits have been invented for use in fuzzy-logic systems. Heretofore, fuzzy membership functions have been implemented, variously,...

Briefs: Electronics & Computers
Regenerative Pseudonoise Ranging

In a proposed improved technique for pseudonoise turnaround ranging of a radio transponder, the pseudonoise modulating signal would be regenerated in the transponder. The net result of the regeneration would be an increase in the effective return ranging power. This increase would provide some margin for...

Briefs: Electronics & Computers
Biomorphic Analog Pulse-Coupled Neural Circuits

Analog electronic circuits that operate with pulsed input and output signals are undergoing development. The pulsing behavior of these circuits is modeled after a similar behavior, called...

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