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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Large scale integration and metal oxide semiconductor microelectronic testing techniques including combinatorial, sequential, functional, and parametric methods
Large scale integration microelectronic wafer and package testing including parametric and functional tests of combinatorial and sequential logic circuits
Application of Apollo space photography and sequential high altitude NASA aircraft photography for evaluating natural and cultural resources in southeastern Arizona - map
Comparison of concatenated and sequential decoding systems and convolutional code structural properties
Convolutional coding, sequential coding, subbaud coding, and inverse systems for data protection
Earth based orbit determination for Mars orbiting spacecraft, comparing batch and sequential tracking filter data processing methods
Microprogramming by Computer Design Language for describing digital computer functional configuration and sequential operation
Error correction coding/decoding techniques integration, discussing convolutional and block coding and Viterbi, Sequential and Threshold decoding algorithms
Optimal reliability of system with nonlinear constraints, using mathematical model and sequential unconstrained minimization technique
Heuristic algorithm for computation of failures detection tests in asynchronous sequential logic circuits
Design parameter optimization for two-stage space shuttle atmospheric flight from spherical nonrotating earth by sequential straight line approximation
Electrical connector is described of zipper-like configuration, in which sequentially interlocking tines serve as electrical contacts or insulators.
Two cylindrical shutter mechanisms having fixed outer sleeves and rotating inner sleeves use single stepping motor and Geneva mechanism to sequentially move optical components into path of ultraviolet monochromator for output control to photomultiplier. Photometric and wavelength calibration sources insure shutter positions according to operational phases.
Three-antenna interferometric system is described for homing on very high frequency transmitters. Antenna signals are sequentially sampled with single receiver and receiver output pulses are held for comparison of signals from outermost antennas with those of center antenna. System can be installed as redundant navigation system in case of failure of VOR receivers.
Daytime wind velocity measurements of the upper atmosphere as function of altitude were supposed to be gathered by Gemini 12 sequential photography of rocket made sodium clouds. Evaluation of the film was indicative that all 26 photographs were overexposed during the photographic sequences. The overexposures were caused by a camera shutter locked in the open position. Therefore, useful photographic data were not obtained for analysis.
The deconditioning effects of weightlessness on the cardiovascular system of astronauts are discussed. It is believed that man cannot tolerate indefinite exposure to weightlessness without considerable circulatory deterioration. Analyses of data collected from space flights to date substantiate these beliefs, and confirm the fact that some form of compensation must be provided to keep the cardiovascular system of space travelers properly conditioned. Sequential pulsatile devices were investigated to produce periodic hydrostatic pressure gradients in the venous system of eight subhuman primates. Intermittent venous pooling of blood in the extremities triggers and stimulates the vascular reflex mechanisms of the cardiovascular system that may have significant benefits in maintaining the circulatory system in proper tone under weightless conditions. Electrocardiograms, blood pressure measurements, cardiac output and stroke volume determinations were used to evaluate the efficiency of the described technique. Results were amazingly consistent to indicate an efficient system for intermittently exercising the heart within safe and medically acceptable limits.
The third phase of remote sensing technologies and potentials applied to the operations of the U.S. Geological Survey is introduced. Remote sensing data with multidisciplinary spatial data from traditional sources is combined with geographic theory and techniques of environmental modeling. These combined imputs are subject to four sequential activities that involve: (1) thermatic mapping of land use and environmental factors; (2) the dynamics of change detection; (3) environmental surveillance to identify sudden changes and general trends; and (4) preparation of statistical model and analytical reports. Geography program functions, products, clients, and goals are presented in graphical form, along with aircraft photo missions, geography test sites, and FY-70.
The application of remote sensors for obtaining geophysical information of the Arctic regions is discussed. Two significant requirements are to acquire sequential, synoptic imagery of the Arctic Ocean during all weather and seasons and to measure the strains in the sea ice canopy and the heterogeneous character of the air and water stresses acting on the canopy. The acquisition of geophysical data by side looking radar and microwave sensors in military aircraft is described.