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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 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Diagnostic accuracy of an ultrasonic multiple transducer cardiac imaging system

An ultrasonic multiple-transducer imaging system for intracardiac structure visualization is developed in order to simplify visualization of the human heart in vivo without radiation hazard or invasion of the body. Results of the evaluation of the diagnostic accuracy of the devised system in a clinical setting for adult patients are presented and discussed. Criteria are presented for recognition of mitral valva prolapse, mitral stenosis, pericardial effusion, atrial septal defect, and left ventricular dyssynergy. The probable cause for false-positive and false-negative diagnoses is discussed. However, hypertrophic myopathy and congestive myopathy were unable to be detected. Since only qualitative criteria were used, it was not possible to differentiate patients with left ventricular volume overload from patients without cardiac pathology.

Popp, R. L.↗
NASA NTRS1976

Biostack 3 experiment MA-107

The Biostack III experiment onboard the Apollo spacecraft during the Apollo Soyuz Test Project complemented the Biostack I and II experiments of the Apollo 16 and 17 missions. The objectives of these experiments were to study the biological effects of individual heavy cosmic particles of high energy loss (HZE) not available on earth, to study the influence of additional space flight factors, to obtain knowledge on the mechanism by which HZE particles damage biological materials, to get information on the spectrum of charge and energy of the cosmic ions in the spacecraft, and to estimate the radiation hazards to man in space.

H. Bucker↗
NASA NTRS1976

Successful large-scale use of CMOS devices on spacecraft traveling through intense radiation belts

This paper describes the environmental models of the radiation belts and computational techniques which have been developed for predicting the radiation hazards for spacecraft. These data and techniques are then applied to the Atmosphere Explorer 51 spacecraft to explain its successful survival for more than 18 months in a severe environment. In particular, the results of the analysis are used to explain the performance of some 2400 CMOS devices, and consequently, they demonstrate the reliability of this device technology in spacecraft systems.

Brucker, G. J.↗
NASA NTRS1977

Industries in space to benefit mankind: A view over the next 30 years

New products, services, and energy sources are available to man through the exploitation of the useful attributes of space and space shuttle operations. Benefits include: (1) industrial fuel conservation through the use of electronic teleconferencing, high temperature turbines, and the space processing of materials; (2) improved health care through the use of biotelemetry, teleoperators, and weightless hospitals; (3) more efficient communication systems such as portable telephones, individual warning devices, and direct satellite broadcasting for educational purposes; (4) more abundant crop growth and controlled climate modification by the use of space-based reflectors to direct the light of the sun and moon to specific areas on earth; (5) solar energy utilization; and (6) reduction in radiation hazards through the use of space-based nuclear fusion reactors.

Source record↗
NASA NTRS1977

Apollo-Soyuz pamphlet no. 6: Cosmic ray dosage

The radiation hazard inside spacecraft is discussed with emphasis on its effects on the crew, biological specimens, and spacecraft instruments. The problem of light flash sensations in the eyes of astronauts is addressed and experiment MA-106 is described. In this experiment, light flashes seen by blindfolded astronauts were counted and high energy cosmic ray intensity in the command module cabin were measured. The damage caused by cosmic ray hits on small living organisms was investigated in the Biostack 3 experiment (MA-107). Individual cosmic rays were tracked through layers of bacterial spores, small seeds, and eggs interleaved with layers of AgCl-crystal wafers, special plastic, and special photographic film that registered each cosmic ray particle passed.

Page, L. W.↗
NASA NTRS1979

Manned Orbital Transfer Vehicle (MOTV). Volume 4: Supporting analysis

Generic missions were defined to enable potential users to determine the parameters for suggested user projects. Mission modes were identified for providing operation, interfaces, performance, and cost data for studying payloads. Safety requirements for emergencies during various phases of the mission are considered with emphasis on radiation hazards.

Boyland, R. E.↗
NASA NTRS1979

Solar-terrestrial Predictions Proceedings. Volume 1: Prediction Group Reports

The current practice in solar terrestrial predictions is reviewed with emphasis of prediction, warning, and monitoring services. Topics covered include: ionosphere-reflected HF radio propagation; radiation hazards for manned space flights and high altitude and high latitude aircraft flights; and geomagnetic activity.

Donnelly, R. F.↗
NASA NTRS1982

Towards understanding solar flares

Instrumentation and spacecraft payloads developed at Lockheed for solar flare studies are reviewed, noting the significance of the observations for adding to a data base for eventual prediction of the occurrence of flares and subsequent radiation hazards to people in space. Developmental work on the two solar telescopes on board the Skylab pallet was performed at a Lockheed facility, as was the fabrication of very-large-area proportional counter for flights on the Aerobee rocket in 1967. The rocket work led to the fabrication of the Mapping X Ray Heliometer on the Orbiting Solar Observatory and the X Ray Polychromator for the Solar Maximum Mission. The Polychromator consists of a bent crystal spectrometer for high time resolution flare studies over a wide field of view, and a flat crystal spectrometer for simultaneous polychromatic imaging at 7 different X ray wavelengths.

Acton, L. W.↗
NASA NTRS1985

Tethered nuclear power for the Space Station

A nuclear space power system the SP-100 is being developed for future missions where large amounts of electrical power will be required. Although it is primarily intended for unmanned spacecraft, it can be adapted to a manned space platform by tethering it above the station through an electrical transmission line which isolates the reactor far away from the inhabited platform and conveys its power back to where it is needed. The transmission line, used in conjunction with an instrument rate shield, attenuates reactor radiation in the vicinity of the space station to less than one-one hundredth of the natural background which is already there. This combination of shielding and distance attenuation is less than one-tenth the mass of boom-mounted or onboard man-rated shields that are required when the reactor is mounted nearby. This paper describes how connection is made to the platform (configuration, operational requirements) and introduces a new element the coaxial transmission tube which enables efficient transmission of electrical power through long tethers in space. Design methodology for transmission tubes and tube arrays is discussed. An example conceptual design is presented that shows SP-100 at three power levels 100 kWe, 300 kWe, and 1000 kWe connected to space station via a 2 km HVDC transmission line/tether. Power system performance, mass, and radiation hazard are estimated with impacts on space station architecture and operation.

Bents, D. J.↗
NASA NTRS1985

Tethered nuclear power for the space station

A nuclear space power system the SP-100 is being developed for future missions where large amounts of electrical power will be required. Although it is primarily intended for unmanned spacecraft, it can be adapted to a manned space platform by tethering it above the station through an electrical transmission line which isolates the reactor far away from the inhabited platform and conveys its power back to where it is needed. The transmission line, used in conjunction with an instrument rate shield, attenuates reactor radiation in the vicinity of the space station to less than one-one hundredth of the natural background which is already there. This combination of shielding and distance attenuation is less than one-tenth the mass of boom-mounted or onboard man-rated shields that are required when the reactor is mounted nearby. This paper describes how connection is made to the platform (configuration, operational requirements) and introduces a new element the coaxial transmission tube which enables efficient transmission of electrical power through long tethers in space. Design methodology for transmission tubes and tube arrays is discussed. An example conceptual design is presented that shows SP-100 at three power levels 100 kWe, 300 kWe, and 1000 kWe connected to space station via a 2 km HVDC transmission line/tether. Power system performance, mass, and radiation hazard are estimated with impacts on space station architecture and operation.

Bents, D. J.↗
NASA NTRS1987

Application of radar for automotive collision avoidance. Volume 1: Technical report

The purpose of this project was research and development of an automobile collision avoidance radar system. The major finding was that the application of radar to the automobile collision avoidance problem deserves continued research even though the specific approach investigated in this effort did not perform adequately in its angle measurement capability. Additional findings were that: (1) preliminary performance requirements of a candidate radar system are not unreasonable; (2) the number and severity of traffic accidents could be reduced by using a collision avoidance radar system which observes a fairly wide (at least + or - 10 deg) field of view ahead of the vehicle; (3) the health radiation hazards of a probable radar design are not significant even when a large number of radar-equipped vehicles are considered; (4) effects of inclement weather on radar operation can be accommodated in most cases; (5) the phase monopulse radar technique as implemented demonstrated inferior angle measurement performance which warrants the recommendation of investigating alternative radar techniques; and (6) extended target and multipath effects, which presumably distort the amplitude and phase distribution across the antenna aperture, are responsible for the observed inadequate phase monopulse radar performance.

Lichtenberg, C. L.↗
NASA NTRS1988

Human exploration of Mars

A systems study is underway of astronaut missions to Mars that could be accomplished over the next four decades. In addition to an emphasis on the transportation and facility infrastructure required for such missions, other relevant technologies and mission constraints are also being considered. These induce on-orbit assembly, trajectory type, launch opportunities, propellant storage, crew size, cabin pressure, artificial gravity, life-support systems, radiation hazards, power/energy storage, thermal control, human factors, communications, abort scenarios, landing techniques, exploration strategies, and science activities. A major objective of the study is to identify enabling and significantly enhancing technologies for accomplishing the goal of the human exploration of Mars.

Clark, Benton C.↗
NASA NTRS1987

Manned Mars systems study

A study is underway to determine attractive system options, perform trade studies, and provide comparative data for astronaut missions to Mars. Because of an emphasis in this work on deriving requirements and candidates for the transportation and facility infrastructure for such missions, all relevant technologies and mission constraints are also being considered. These include on-orbit assembly, trajectory type, launch opportunities, propellant storage, crew size, cabin pressure, artificial gravity, life-support systems, radiation hazards, power/energy storage, thermal control, human factors, communications, abort scenarios, landing techniques, exploration strategies and science activities. It is planned to scope several example missions and to identify enabling and significantly enhancing technologies for accomplishing the goals of the human exploration of Mars.

Benton C Clark↗
NASA NTRS1989

Current status and future direction of NASA's Space Life Sciences Program

The elements of the NASA Life Sciences Program that are related to manned space flight and biological scientific studies in space are reviewed. Projects included in the current program are outlined and the future direction of the program is discussed. Consideration is given to issues such as long-duration spaceflight, medical support in space, readaptation to the gravity field of earth, considerations for the Space Station, radiation hazards, environmental standards for space habitation, and human operator interaction with computers, robots, and telepresence systems.

White, Ronald J.↗
NASA NTRS1989

Consideration for solar system exploration - A system to Mars

Biomedical issues related to a manned mission to Mars are reviewed. Consideration is given to cardiovascular deconditioning, hematological and immunological changes, bone and muscle changes, nutritional issues, and the development of physiological countermeasures. Environmental issues are discussed, including radiation hazards, toxic chemical exposure, and the cabin environment. Also, human factors, performance and behavior, medical screening of the crew, disease prediction, and health maintenance are examined.

Nicogossian, Arnauld E.↗
NASA NTRS1991

Humans in Earth Orbit and Planetary Exploration Missions; IAA Man in Space Symposium, 8th, Tashkent, Uzbek SSR, Sept. 29-Oct. 3, 1990, Selection of Papers

The present conference on findings from space life science investigations relevant to long-term earth orbit and planetary exploration missions, as well as considerations for future research projects on these issues, discusses the cardiovascular system and countermeasures against its deterioration in the microgravity environment, cerebral and sensorimotor functions, findings to date in endocrinology and immunology, the musculoskeletal system, and health maintenance and medical care. Also discussed are radiation hazards and protective systems, life-support and habitability factors, and such methodologies and equipment for long space mission research as the use of animal models, novel noninvasive techniques for space crew health monitoring, and an integrated international aerospace medical information system.

Grigor'ev, A. I.↗
NASA NTRS1989

Near Zone: Basic scattering code user's manual with space station applications

The Electromagnetic Code - Basic Scattering Code, Version 3, is a user oriented computer code to analyze near and far zone patterns of antennas in the presence of scattering structures, to provide coupling between antennas in a complex environment, and to determine radiation hazard calculations at UHF and above. The analysis is based on uniform asymptotic techniques formulated in terms of the Uniform Geometrical Theory of Diffraction (UTD). Complicated structures can be simulated by arbitrarily oriented flat plates and an infinite ground plane that can be perfectly conducting or dielectric. Also, perfectly conducting finite elliptic cylinder, elliptic cone frustum sections, and finite composite ellipsoids can be used to model the superstructure of a ship, the body of a truck, and airplane, a satellite, etc. This manual gives special consideration to space station modeling applications. This is a user manual designed to give an overall view of the operation of the computer code, to instruct a user in how to model structures, and to show the validity of the code by comparing various computed results against measured and alternative calculations such as method of moments whenever available.

Marhefka, R. J.↗
NASA NTRS1992

Biostack (14-IML-1)

The Biostack experiments address especially the biological effects of the galactic particles of high atomic number and high energy, called HZE particles. The objective of the experiments is to substantiate the assessment of spaceflight radiation hazards especially regarding these particles.

Buecker, H.↗