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Briefs: Electronics & Computers
An improved design for a conical log-spiral antenna (see Figure 1) simplifies construction and improves alignment. The radiating-element substructure of such an antenna must be properly...
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Briefs: Software
Programming Language for Automated Scheduling and Planning
The ASPEN Modeling Language (AML) has been developed for use in the Automated Scheduling and Planning Environment (ASPEN) software system. As described in prior NASA Tech Briefs articles, ASPEN is an object-oriented system that contains a modular, reconfigurable, reusable set of...
Briefs: Software
Communication Software for Distributed Application Programs
The Task Remote Asynchronous Message Exchange Layer (Tramel) software reduces the costs of distributing application programs across computer networks, including the Internet. Tramel implements robust, reliable, simple, highly portable interprocess communication, such that distributed...
Briefs: Software
Software for Coordinating Multiple Exploratory Robots
A computer program coordinates the activities of multiple instrumented robotic vehicles of the "rover" type intended for use in scientific exploration. The program is a master/slave, distributed version of the ASPEN planning software, other versions of which have been reported in several...
Briefs: Software
Program Creates Code to Parse Text
Saxj is a computer program that facilitates the development of programs that parse textual input in the Java programming language. Saxj is a parser generator that creates static Java parsers in the same sense in which YACC, Bison, and YACC++ are static parser generators that create static C-language parsers....
Briefs: Software
Program Creates Java Lexical Analyzers
Luthorj is a computer program that creates static lexical analyzers in the Java programming language, in the same sense in which Flex and Lex create lexical analyzers in the C programming language. The majority of users of Luthorj are expected to be familiar with Lex, and Luthorj parses input files that...
Briefs: Software
Program for Evaluating Spacecraft Designs and Missions
Design for X (DFX) is a computer program that assists, at the prelimary stage of planning, in the evaluaiton of alternative spacecraft designs and mission scenarios. The input required by DFX includes a set of operations goals (scientific and engineering goals and constraints), a mathematical...
Briefs: Mechanical & Fluid Systems
A double-resonator design has been devised for a cloverleaf-shaped silicon microelectromechanical resonator. The double-resonator design provides for an inner, higher-frequency resonator suspended on an outer,...
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Briefs: Mechanical & Fluid Systems
Mechanical Breakaway Clutch
A proposed mechanical breakaway clutch would not rely on friction. The clutch would be useful in environments in which the inherent inaccuracies of friction would make friction clutches erratic. The proposed clutch would comprise two primary assemblies: a driver assembly and a slip flange. The slip flange would be an...
Briefs: Mechanical & Fluid Systems
Molten-Carbonate Oxidation of Solid Waste
The molten-carbonate oxidation (MCO) process shows promise as a means of safe disposal and/or recycling of solid waste. The MCO process is being developed for use in regenerative life-support systems in outer space, but may also prove useful in managing institutional, industrial, and/or municipal solid...
Briefs: Mechanical & Fluid Systems
An improved robotic water-jet system for stripping paint from a ship or other large metallic structure is undergoing development. In addition to utilizing a high-pressure water jet to...
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Briefs: Manufacturing & Prototyping
Microwave heating is the basis of a simple technique for quickly and gently bonding two metallized dielectric or semiconductor wafers to each other. The technique can be used, for example, to...
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Briefs: Medical
"Breathprint" Analysis of Microbial Communities
A technique for assessing changes in the densities and compositions of communities of microorganisms in environmental samples is based partly on redox chemistry. Suspensions of microbes from environmental samples are inoculated into 95-well microtiter plates. Each well contains an initially...
Briefs: Photonics/Optics
Linear arrays of thermopile infrared detectors made of high-performance thermoelectric materials have been fabricated on silicon substrates by micromachining processes. Such detector...
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Briefs: Medical
Macroextraction for Purification of Nucleic Acids
A technique for extracting samples of ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) for use in diagnosing and studying infectious and genetic diseases has been developed. The technique enables the concentration and purification of nucleic acids from large (in comparison with older...
Briefs: Photonics/Optics
A single-laser-based, heterodyne optoelectronic system that measures the displacements of two targets along the same lines of sight has been developed. Heretofore, it would have been necessary to...
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Briefs: Physical Sciences
Simple fiber-optic couplers have been devised for use in coupling light into and out of the "whispering-gallery" electromagnetic modes of transparent microspheres. The need for this type of...
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Briefs: Photonics/Optics
A spatially modulated prism interferometer (SMPI) has been developed that overcomes the complexities of traditional interferometers and the inherent limitations of diffraction gratings, dispersion...
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Briefs: Physical Sciences
A diffraction grating consisting of a periodic gradient in the index of refraction of a thin surface layer has been shown to be effective as a means of far-field coupling of monochromatic...
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Briefs: Photonics/Optics
Several high-fidelity imaging spectrometers have been designed with convex diffraction gratings for wavelengths ranging from the ultraviolet to the thermal infrared. All the designs...
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Briefs: Photonics/Optics
A method of determining sizes of particles suspended in liquids and engaging in Brownian motion involves statistical analysis of counts of photons of laser light scattered by the...
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Briefs: Photonics/Optics
A stroboscopic scanning electron microscope (SEM) has been proposed as a means of generating still or slow-motion pictures of moving structures in microelectromechanical systems (MEMS). Such...
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Briefs: Test & Measurement
A Mass-Spectrometer System for Detecting Gas Leaks
The Hydrogen Umbilical Mass Spectrometer (HUMS) consists of an integrated sample delivery system, a commercial mass-spectrometer-based gas analyzer, and a set of calibration gas mixtures traceable to NIST (National Institute for Standards and Technology). The system, except for the calibration gas...
Briefs: Photonics/Optics
A proposed optoelectronic system based on imaging-lidar and differential-altimetry techniques would generate data equivalent to a height map of a surface area. Originally conceived for use in...
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Briefs: Imaging
A new design for a complementary metal oxide/semiconductor (CMOS) snapshot imaging device of the photodiode-based, active-pixel-sensor (APS) type calls for features to prevent...
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Briefs: Motion Control
Advanced, Lightweight, Low-Power-Consumption Actuator Brake
An advanced, lightweight, low-power consumption brake has been developed to satisfy NASA's special requirements for use on actuators during spaceflight. This brake can increase the stopping, holding, and parking ability of a spacecraft while reducing its electrical power consumption. Two...
Briefs: Photonics/Optics
Miniature high-resolution optical-absorption sensors for detecting trace amounts of chemical species of interest in gas and liquid samples are undergoing development. The transducer in a...
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Briefs: Motion Control
A method of computing the speed at which to command an autonomous robotic vehicle to travel over rough terrain has been devised. The method amounts to a robotic implementation of the...
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Briefs: Photonics/Optics
A proposed optoelectronic apparatus would perform the combined functions of a confocal microscope and a Raman spectrometer. It would be used to acquire Raman-spectral-image and/or...
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