Briefs: Electronics & Computers
Fatigue cracks and plastic deformation of parts in jet aircraft engines could be detected, even during engine operation, by use of proposed in situ monitoring devices called "wireless...
Briefs: Motion Control
Electronic circuitry has been devised to compensate for variations in the resonance quality factor (Q) of a planar vibratory microgyroscope like that described in the first of the...
Briefs: Physical Sciences
A computer program (see figure) has been developed to serve as a time- and cost-effective means of automating thermal analyses of such hypersonic flight systems as the space shuttle orbiter, the...
Briefs: Physical Sciences
A computer program written within the Mathematica software system automatically generates FORTRAN computer codes that numerically simulate, with high accuracy, the acoustical physics...
Briefs: Physical Sciences
Dryden Flight Research Center has developed a computer program that performs signal management for analysis in real time (SMART). This program, called "SMART," has been effectively used since 1991 in...
Briefs: Mechanical & Fluid Systems
Micromechanics Analysis Code With Generalized Method of Cells (MAC/GMC) is a comprehensive, user-friendly, efficient computer program that predicts the elastic and inelastic thermomechanical responses of continuous and discontinuous composite materials with arbitrary internal microstructures and...
Briefs: Information Technology
Forth Source Code Analysis Tool Set (FSCATS) is a computer program that provides a wide range of capabilities for documenting, analyzing, and reverse-engineering computer programs written in the Forth...
Briefs: Electronics & Computers
Planar arrays of cadmium zinc telluride photodetectors with readout electronic circuitry have been developed for use as hard-x-ray and y-ray image sensors. When a coded,...
Briefs: Materials
Ceramics Analysis and Reliability Evaluation of Structures/Creep (CARES/CREEP) is a computer program that predicts the creep lives of ceramic structural components. [CARES/CREEP should not be...
Briefs: Physical Sciences
The presence of corrosives in the Earth's atmosphere is of global concern. From acid rains that are destroying forests and disfiguring monuments like the Parthenon and the pyramids, to atmospheric pollutants that produce...
Briefs: Physical Sciences
A method of controlling the crystal-growth habit in directional freezing has been devised. A substance can be purified by directional-freeze crystallization, wherein (1) the liquid phase of the substance is partially frozen, causing impurities to become preferentially concentrated in the...
Briefs: Electronics & Computers
A transceiver has been developed to serve as a data-communication link between (1) the RS-232-standard serial communication port of a personal computer (PC) running the Windows 95 or Windows NT operating system...
Briefs: Electronics & Computers
Special-purpose, "intelligent," computer-controlled, highly miniaturized radio transceivers have been proposed for use in monitoring critical and/or valuable pieces of equipment. These...
Briefs: Electronics & Computers
A method of designing fault-tolerant networks of computers and other electronic circuits has been conceived with a view toward minimizing costs by utilizing commercial off-the-shelf (COTS)...
Briefs: Photonics/Optics
Irradiation by the beam from a CO2laser has been found to be an effective means of marking a black anodized aluminum surface. In general, this process works on any dark anodized surface....
Briefs: Photonics/Optics
A proposed focal-plane array (FPA) of quantum-well infrared photodetectors (QWIPs) would sense images in three different infrared wavelength bands simultaneously. These and other QWIP infrared...
Briefs: Electronics & Computers
A method of correcting for defective pixels in an integrated-circuit image sensor of the active-pixel sensor (APS) type has been proposed. The corrections would be made by additional...
Briefs: Photonics/Optics
Two reports present additional information on the subject matter of "Software for Processing Data in Particle-Image Velocimetry" (LEW-16857),NASA Tech Briefs, Vol. 24, No. 1 (January 2000), page 26a. Like the cited prior article, both reports discuss the principles and the practical aspects of...
Briefs: Mechanical & Fluid Systems
Surface micromachined silicon carbide accelerometers are undergoing development for eventual use in high-temperature environments like those inside turbines, internal-combustion engines, and...
Briefs: Photonics/Optics
Random reflectors of a proposed type would be fabricated on the back surfaces of quantum-well infrared photodetectors (QWIPs) to increase the coupling efficiency of infrared light into the QWIPs in two...
Briefs: Physical Sciences
A theoretical model that predicts the time-dependent behavior of a pyrotechnically actuated mechanism and a computer program that implements the model have been developed. The model and program are especially applicable to a pyrotechnic device known as the NASA Standard Initiator (NSI)....
Briefs: Photonics/Optics
Tridirectional diffraction gratings have been proposed to provide optical coupling to quantum-well infrared photodetectors (QWIPs) in focal-plane arrays. The tridirectional gratings would...
Briefs: Physical Sciences
Image-plane multidither sensing has been found to be suitable for adaptive wavefront correction in a large telescope in which the main optic is a precise reflector divided into lightweight, controllably actuated segments. In image-plane multidither sensing, the telescope is aimed at a star...
Briefs: Photonics/Optics
A proposal for development of a class of high-transmission and antireflection optical filters is derived from the observation that the eyes of moths reflect almost no light, regardless of the wavelength or the angle of incidence of illumination. The low-reflection property of moth eyes...
Briefs: Physical Sciences
Ceramic static-strain gauges capable of generating mechanical-strain signals much larger than spurious thermal signals have been invented. These gauges are intended for use at temperatures from room temperature to 1,250 °C. Heretofore, external circuits have been used to provide temperature...
Briefs: Photonics/Optics
Organic light-emitting diodes (OLEDs) are grounded in a self-luminous display technology based on thin organic films as the light emitter. Like conventional inorganic light-emitting...
Briefs: Physical Sciences
Magnetostrictive actuators that would hold their displacements with power turned off have been proposed for use at temperatures from about 10 to about 77 K. Such "set and hold with power off"...
Briefs: Photonics/Optics
A simplified microwave radiometric apparatus has been proposed for use in quantifying the potential danger of accretion of ice onto an aircraft flying through a cloud. The quantity of...
Briefs: Sensors/Data Acquisition
Electrobiotic sensors have been proposed for detecting toxic substances in a variety of environments. Electrobiotic sensors would be inexpensive, compact units that would be easy to use and could be deployed...