July 1998

Stories

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Briefs: Electronics & Computers
Single-Event Latchup Protection of Integrated Circuits
Many commercially available advanced-technology CMOS and bipolar integrated circuits are susceptible to single-event latchup (SEL) effects caused by heavy ions or protons from cosmic rays or solar flares, making them unsuitable for satellite applications. Remanufacturing the integrated circuits...
Briefs: Electronics & Computers
The term "inverse rectenna" may seem like an oxymoron at first glance. However, preliminary experiments have demonstrated that a rectenna of suitable design can be made to operate in an...
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Briefs: Electronics & Computers
As electronic circuits become more densely packaged and higher in power, maintaining them within permissible temperature ranges becomes a major issue. This is especially true in the case of...
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Briefs: Electronics & Computers
SQUID-Based Asymmetric Planar Gradiometer
Berkeley Laboratory researchers have demonstrated a novel superconducting gradiometer that helps to reduce ambient magnetic field noise generated by relatively distant sources in favor of tiny magnetic signals generated by a local source. This is another step toward the operation of SQUID-based instruments...
Briefs: Mechanical & Fluid Systems
Automatic valves have been proposed for shutting off flows of liquids when abnormally large accelerations occur. These valves could be used, for example, to prevent outflows of...
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Briefs: Robotics, Automation & Control
Lightweight, inflatable robotic vehicles (rovers) that superficially resemble beach balls and that could be driven by wind and/or electric power are undergoing development. These rovers were conceived...
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Briefs: Electronics & Computers
An electronic system that comprises airborne and ground-based subsystems generates data for a global real-time interactive map (GRIM) that displays the current position and velocity...
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Briefs: Mechanical & Fluid Systems
The Spacecraft Autonomous Navigation System using GPS for Earth Orbiters (SANS-GEO) computer program is designed to perform the navigation calculations that will enable the New...
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Briefs: Electronics & Computers
A method for reducing the number of bits of quantization of synaptic weights during training of an artificial neural network involves the use of the cascade back-propagation learning...
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Briefs: Mechanical & Fluid Systems
The Multiple Interferometric Ranging Analysis using GPS Ensemble (MIRAGE) computer program processes spacecraft-tracking data to determine orbits of single satellites, or of...
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Briefs: Electronics & Computers
A data-communication and -processing network of compact, laptop-computer-based portable stations communicating via the World Wide Web (WWW) has been proposed as a relatively inexpensive...
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Briefs: Mechanical & Fluid Systems
A mathematical model that includes layerwise finite elements has been developed for use in numerical simulation of the coupled electrical, mechanical, and thermal responses of composite...
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Briefs: Mechanical & Fluid Systems
A new joint, proposed for use on an attachable debris shield for the International Space Station Service Module, has potential for commercial use in situations where hardware must be assembled...
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Briefs: Physical Sciences
Quasi-thermostatic gas-gap thermal switches have been proposed. These switches would operate automatically, would contain no moving parts, would not require power supplies or controls, would not...
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Briefs: Robotics, Automation & Control
The Eclipse flight project was established to demonstrate a reusable-launch-vehicle concept developed by Kelly Space and Technology, Inc. An F-106 delta-wing aircraft was chosen as the towed...
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Briefs: Electronics & Computers
A focal-plane array (FPA) of GaAs-based quantum-well infrared photodetectors (QWIPs) that would detect images in two wavelength bands simultaneously is undergoing development. From ratios...
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Briefs: Materials
GENOA is an advanced, completely integrated, hierarchical software package for computationally simulating the thermal and mechanical responses of high-temperature composite materials...
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Briefs: Materials
Ion-beam-deposited surface layers of diamond-like carbon (DLC) on fine-grain chemical-vapor-deposited (CVD) diamond have been found to be effective in reducing friction and wear in a...
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Briefs: Robotics, Automation & Control
The figure illustrates various aspects of a proposed mechanism that would be mounted in an instrumented penetrator dart for use in acquiring a sample of soil. In operation, the dart would be...
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Briefs: Electronics & Computers
Delta-Doped CCDs for Measuring Energies of Positive Ions
Research closely related to that reported in the preceding article has shown that δ-doped charge-coupled devices (CCDs) could be used to detect incident protons and perhaps other positive ions, and to measure the kinetic energies of the ions, down to about 1.25 keV. Prior to the development...
Briefs: Robotics, Automation & Control
Microscopic forced-flow heat-transfer systems containing heat exchangers, flow channels, electrostatically driven peristaltic pumps, and related components have been proposed. These...
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Briefs: Electronics & Computers
Charge-coupled devices (CCDs) of a type developed previously for imaging in ultraviolet light have been found to be useful as detectors of electrons and other charged particles with kinetic...
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Briefs: Materials
Two poly(arylene ether phosphine oxide)s (PAEPOs) have been found to be suitable as matrix and coating materials for composite-material (matrix/fiber) tanks and pipes that contain liquid...
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Briefs: Robotics, Automation & Control
A methodology for designing robots provides for satisfying both safety and performance requirements. Heretofore, most robot-design efforts have been focussed on maximizing performance, with only incidental...
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Briefs: Mechanical & Fluid Systems
Detailed measurements of complex flow fields within the NASA Low Speed Centrifugal Compressor (LSCC) have been acquired. The measurement data provide insight into the fundamental...
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