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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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At least 1,063 records · Page 59

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NASA NTRS1975

Comparison of magnetospheres and radio emissions of Jupiter with earth

The magnetosphere and radio emission of Jupiter is compared with those of the earth. It was predicted that Jupiter would have a Van Allen belt at a radius such that its magnetic field strength would be about equal to that in earth's Van Allen belt and that Jupiter's moon Io travels in the Van Allen belt. Because of Io's low conductivity, plasma sweeping past hits Io, producing a turbulent plasma proboscis which forms hydrodynamic shocks. These shocks travel down the magnetic field lines to the Jovian magnetosphere where they stimulate electron cyclotron emission and free radical spin-flip emission. The free radicals likely to exist abundantly and the richness of the likely decametric frequencies resulting from the many g values of the free radicals are discussed.

Libby, L. M.↗

NASA NTRS1976

The Venusian surface

Numerous questions generated by past Soviet and U.S. Venus missions regarding the climate and history of Venus have stimulated the initiation of a new U.S. program of Venus probes and orbiters. Among the issues that these missions are intended to resolve are the intensity of sunlight reaching the surface of the planet, the extent and composition of the cloud layer, and the mechanisms responsible for the extremely high surface temperatures measured by earlier probes. Also of interest are the reasons for the sharply differing terrains revealed by the Soviet probes Venera 9 and 10. Clarification of such questions may be expected to improve understanding of the origin of life on earth.

Rasool, S. I.↗

NASA NTRS1976

ERDA-NASA wind energy project ready to involve users

The NASA contribution to the Wind Energy Project is discussed. NASA is responsible for the following: (1) identification of cost-effective configurations and sizes of wind-conversion systems, (2) the development of technology needed to produce these systems, (3) the design of wind-conversion systems that are compatible with user requirements, particularly utility networks, and (4) technology transfer obtained from the program to stimulate rapid commercial application of wind systems. Various elements of the NASA program are outlined, including industry-built user operation, the evaluation phase, the proposed plan and schedule for site selection and user involvement, supporting research and technology (e.g., energy storage), and component and subsystem technology development.

Thomas, R.↗

NASA NTRS1976

The effect of attention loading on the inhibition of choice reaction time to visual motion by concurrent rotary motion

This study investigates the influence of attention loading on the established intersensory effects of passive bodily rotation on choice reaction time (RT) to visual motion. Subjects sat at the center of rotation in an enclosed rotating chamber and observed an oscilloscope on which were, in the center, a tracking display and, 10 deg left of center, a RT line. Three tracking tasks and a no-tracking control condition were presented to all subjects in combination with the RT task, which occurred with and without concurrent cab rotations. Choice RT to line motions was inhibited (probability less than .001) both when there was simultaneous vestibular stimulation and when there was a tracking task; response latencies lengthened progressively with increased similarity between the RT and tracking tasks. However, the attention conditions did not affect the intersensory effect; the significance of this for the nature of the sensory interaction is discussed.

Looper, M.↗

NASA NTRS1976

Eye movements - On-line measurement, analysis, and control

The paper outlines the plans and progress related to the development of a Programmed Eye-track Recording System and Eye-coupled Ubiquitous Scene-generator known by the acronym PERSEUS. Particular attention is given to the design and implementation of a computer-based real-time eye-tracking system with associated digital scenic display capability. The accurate eye-tracker developed by Cornsweet and Crane (1973) is selected for this purpose. The discussion covers automatic detection of fixations and saccades, automatic scanpath analysis, fixation-conditional stimulation, and digital scene generation. The all-digital approach to scenic simulation not only eliminates the camera optics and electromechanical servomechanisms of TV-model systems of simulation but also opens the way to the virtually unlimited sequencing of data-base contents and perspectives thereof.

Anliker, J.↗

NASA NTRS1975

Mechanisms of radio-protection by catecholamines in the hamster /Mesocricetus auratus/

Experiments were conducted on normal and splenectomized male and female hamsters between 2 and 3 months old subjected to a whole-body exposure of 1000 or 2000 rads in a Co-60 source with a view toward evaluating their radio-protection by norepinephrine, isoproterenol, and phenylephrine. Vasoconstriction hypoxia mechanism of radio-protection is examined along with the hypothesis that isoproterenol protects by hypercalcemia-induced cell proliferation. Radiation experiment results are found to be consistent with the hypothesis that stimulation of alpha receptors results in radio-protection through a tissue hypoxia mechanism. Beta agonists seem to protect by a hypotensive-hypoxia mechanism. The catecholamines protect against the hematopoietic syndrome, but show no evidence of protection against the gastrointestinal syndrome.

Prewitt, R. L.↗

NASA NTRS1963

The Commercial Application of Missile/Space Technology, Parts 1 and 2

This report is concerned with the transfer of technology from missile and space programs to non-missile/space applications in the United States. It presents the findings of a University of Denver Research Institute study sponsored by a National Aeronautics and Space Administration (NASA) grant awarded in November 1961. Initial stimulation for the unsolicited proposal leading to this study came from a 1960 Brookings Institution report to NASA, Proposed Studies on the Implications of Peaceful Space Activities for Human Affairs.

Welles, John G.↗

NASA NTRS1976

Dynamic response of cavitating turbomachines

Stimulated by the pogo instability encountered in many liquid propellant rockets, the dynamic behavior of cavitating inducers is discussed. An experimental facility where the upstream and downstream flows of a cavitating inducer could be perturbed was constructed and tested. The upstream and downstream pressure and mass flow fluctuations were measured. Matrices representing the transfer functions across the inducer pump were calculated from these measurements and from the hydraulic system characteristics for two impellers in various states of cavitation. The transfer matrices when plotted against the perturbing frequency showed significant departure from steady state or quasi-steady predictions especially at higher frequencies.

Ng, S. L.↗

NASA NTRS1976

Caltech/JPL Conference on Image Processing Technology, Data Sources and Software for Commercial and Scientific Applications

Recent advances in image processing and new applications are presented to the user community to stimulate the development and transfer of this technology to industrial and commercial applications. The Proceedings contains 37 papers and abstracts, including many illustrations (some in color) and provides a single reference source for the user community regarding the ordering and obtaining of NASA-developed image-processing software and science data.

Redmann, G. H.↗

NASA NTRS1976

An advanced concept that promises ecological and economic viability

The actuality of supersonic commercial service being provided by Concorde is demonstrating to the world the advantages offered by supersonic travel for both business and recreation. Public acceptance will gradually and persistently stimulate interest to proceed with a second generation design that meets updated economic and ecological standards. It is estimated that this concept could operate profitably on world-wide routes with a revenue structure based upon economy fares. Airplanes will meet all present day ecological requirements regarding noise and emissions.

Wright, B. R.↗

NASA NTRS1976

NASA Symposium 76

New Mexico State University and the National Aeronautics and Space Administration hosted a symposium to promote NASA's efforts to increase the available pool of minority and women scientists and engineers to meet affirmative hiring goals. The conferences also provided an opportunity for key NASA officials to meet with appropriate officials of participating institutions to stimulate greater academic interest (among professors and students) in NASA's research and development programs. Minority aerospace scientists and engineers had opportunity to interact with the minority community, particulary with young people at the junior high, high school, and college levels. One aim was to raise minority community's level of understanding regarding NASA's Regional Distribution System for storage and retrieval of scientific and technical information.

Source record↗

NASA NTRS1977

Design and performance of energy efficient propellers for Mach 0.8 cruise

The increased emphasis on fuel conservation in the world has stimulated a series of studies of both conventional and unconventional propulsion systems for commercial aircraft. Preliminary results from these studies indicate that a fuel saving of 14 to 40 percent may be realized by the use of an advanced high-speed turboprop. This turboprop must be capable of high efficiency at Mach 0.8 cruise above 9.144 km altitude if it is to compete with turbofan powered commercial aircraft. Several advanced aerodynamic concepts were investigated in recent wind tunnel tests under NASA sponsorship on two propeller models. These concepts included aerodynamically integrated propeller/nacelles, area ruling, blade sweep, reduced blade thickness and power (disk) loadings several times higher than conventional designs. The aerodynamic design methodology for these models is discussed. In addition, some of the preliminary test results are presented which indicate that propeller net efficiencies near 80 percent were obtained for high disk loading propellers operating at Mach 0.8.

Mikkelson, D. C.↗

NASA NTRS1977

NASA Space Sciences Symposium-1977

The primary objective of the symposium was to motivate American Indians and other minority youths and women to select science and engineering as viable career choices, thereby making them available to the technical work force. Other objectives were: (1) to determine how aerospace technology careers and aerospace activities can be made more relevant to minorities and women; (2) to provide an opportunity for key NASA officials to interact with teachers and counselors of the participating schools; (3) to stimulate a greater interest among American Indian organizations and students in NASA's research and development programs; (4) to help NASA's efforts in the recruiting of minorities and women into its work force; and (5) to provide opportunities for minority aerospace scientists and engineers to interact with the minority community, particularly with youths at the junior high school and high school levels.

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NASA NTRS1977

Recent developments in photovoltaic energy by ERDA/NASA-LeRC

Application development activities were designed to stimulate the market for photovoltaics so that as costs are reduced there will be an increasing market demand to encourage the expansion of industrial solar array production capacity. Supporting these application development activities are tasks concerned with: (1) establishing standards and methodology for terrestrial solar cell calibration; (2) conducting standard and diagnostic measurements on solar cells and modules; and (3) conducting real time and accelerated testing of solar cell modules and materials of construction under outdoor sunlight conditions.

Deyo, J. N.↗

NASA NTRS1977

Experiment M131. Human vestibular function

The lower susceptibility to vestibular stimulation aloft, compared with that on ground under experimental conditions, is attributed to a precondition, namely, either there is no need to adapt, or, as exemplified by the Skylab 3 pilot, adaptation to weightlessness is achieved. Findings in some of the astronauts emphasize the distinction between two categories of vestibular side effects: immediate reflex phenomena (illusions, sensations of turning, etc.), and delayed epiphenomena that include the constellation of symptoms and syndromes comprising motion sickness. The drug combinations 1-scopolamine and d-amphetamine and promethazine hydrochloride and ephedrine sulfate are effective in prevention and treatment of motion sickness. It is concluded that prevention of motion sickness in any stressful motion environment involves selection, adaptation, and the use of drugs.

Graybiel, A.↗

NASA NTRS1976

Effects of head-down tilt on fluid and electrolyte balance

The metabolic effects of -5 deg tilt were studied in eight normal individuals. Exposure to tilt for 24 hr increased sodium excretion and decreased plasma volume. Plasma renin activity and plasma aldosterone levels were not significantly different from supine values during the first 6 hr of tilting, but were increased significantly at the end of the 24-hr tilt period. Creatinine clearance and potassium balance were not affected by the tilt. These findings indicate that head-down tilt induces a sodium diuresis and stimulation of the renin-angiotensin-aldosterone system.

Volicer, L.↗

NASA NTRS1976

Photovoltaic test and demonstration project

The considered project consists of three subprojects related to applications, device performance and diagnostics, and endurance testing. The objectives of the applications subproject include the determination of the operating characteristics for a variety of photovoltaic conversion systems. A system test facility is being constructed in this connection and a prototype residence experiment is to be conducted. Market demand for solar cells is to be stimulated by demonstrating suitability of solar cells for specific near-term applications. Activities conducted in connection with device performance studies and diagnostics are also discussed along with developments in the area of endurance testing.

Forestieri, A. F.↗

NASA NTRS1977

Reduction in plasma vasopressin levels of dehydrated rats following acute stress

Results are presented for an investigation directed to substantiate and extend preliminary findings of stress-induced reduction in plasma arginine vasopressin (pAVP). Since normally hydrated rats have very low levels of pAVP, it is difficult to measure reliably any decrease in pAVP that may result from stress. To overcome this problem, the pAVP levels of the tested rats were raised by dehydration prior to application of stress. A radioimmunoassay for pAVP is described and used to determine the levels of vasopressin in the plasma of nondehydrated and dehydrated rats after exposure to ether or acceleration stress. Plasma pAVP is also determined in rats following nicotine administration. It is shown that exposure of nondehydrated rats to ether or acceleration stress does not elicit any significant alterations in circulating pAVP levels while nicotine injections stimulate a marked increase. In particular, ether and acceleration stress produce a rapid reduction in the pAVP level of dehydrated rats, the decrease being observed in both large and small animals. The mechanism for this reduction in pAVP level following stress is yet unknown.

Keil, L. C.↗