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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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Magnetically coupled tunnel diode oscillator with square loop core, calculating leakage and source inductances effect on switching pattern
Biosatellite 3 onboard camera time lapse photography of monkey sleep/wake activity patterns during weightlessness
Shaped beam radiation patterns synthesis by iterative sampling method with line sources or uniformly spaced antenna arrays
Far field diffraction pattern of corner reflector for normally incident monochromatic light, considering polarization characteristics
Recirculation patterns in coaxial steady laminar mixing of homogeneous jets in confined tube, solving Navier-Stokes equations
High resolution X ray diffraction patterns of yeast phenylalanyl transfer RNA crystals, discussing double helical regional distribution characteristics
Space shuttle vehicle models, calculating surface flow patterns and pressure and aerodynamic heating distributions for comparison with test data
Lunar near-side tectonic patterns including mare ridges, rills, ridges crater walls features within maria from Lunar Orbiter photographs
Walsh functions in image processing, rotational feature selection and pattern recognition, defining set of orthogonal transformations
Auroral electron and proton precipitation patterns, measuring airglow emissions
Geographic distribution pattern of Australasian tektites, considering origin and crater theory of tektite events
Diurnal water and food intake and body weight changes pattern in rats with hypothalamic lesions
Circular sun synchronous earth satellites, investigating swathing patterns control by orbit selection and modification
The objectives of the pattern recognition tasks are to develop (1) a man-machine interactive data processing system; and (2) procedures to determine effective features as a function of time for crops and soils. The signal analysis and dissemination equipment, SADE, is being developed as a man-machine interactive data processing system. SADE will provide imagery and multi-channel analog tape inputs for digitation and a color display of the data. SADE is an essential tool to aid in the investigation to determine useful features as a function of time for crops and soils. Four related studies are: (1) reliability of the multivariate Gaussian assumption; (2) usefulness of transforming features with regard to the classifier probability of error; (3) advantage of selecting quantizer parameters to minimize the classifier probability of error; and (4) advantage of using contextual data. The study of transformation of variables (features), especially those experimental studies which can be completed with the SADE system, will be done.
The near field antenna pattern of an obstructed optical transmitter, such as a Cassegrainian telescope, has been computed using the Fresnel approximation to the scalar diffraction integral. A number of cases have been considered. These include uniformly illuminated, obstructed circular apertures, and apertures coherently illuminated with a divergent gaussian beam wave. Other beam profiles that may be derived by energy redistribution of the laser beam have also been considered. The techniques used for the numerical evaluation of the Fresnel integral are discussed and results for the optical systems to be used on the High Altitude Aircraft Optical Communications Experiment are presented.
Composite photographs of the surface flow and shadowgraphs of the shock wave pattern are presented that depict the hypersonic flow field of a typical delta wing space shuttle orbiter. Results from a wind tunnel test in air are given in side, oblique, and projected plan views for angles of attack from 0 to 60 deg. The tests were conducted at a Mach number of 7.4 and for Reynolds numbers based on body length of 6,000,000 and 9,000,000. The interrelationship is shown for the intersecting bow and wing leading edge waves with the surface flow for angles of attack for which: (1) the leading edge wave is attached, and (2) the leading edge wave is detached.
Simulation and interpretation of aerial or orbital TV and photographic observations of earth geographic patterns
A conditioning method was used to investigate the orientational responses of ducks as affected by manipulations of the stellar patterns in a planetarium. Under simulated natural skies it was possible to train a bird to a particular direction successively under all positions of the rotating sphere at a constant latitude. The responses were independent of the phase relationships between local time, season, and appearance of the sky provided the bird had been trained under the particular sector of the sphere some time before.