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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 217 records · Page 12
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NASA NTRS1978

Highlights of 1978 activities

General highlights of NASA's activities for 1978 are presented. The highlights are categorized into topics such as space science, space transportation systems, space and terrestrial applications, environment, technology utilization, aeronautics, space research and technology, energy programs, and international. A list of the 1978 launches including: (1) launch date; (2) payload designation; (3) launch vehicle; (4) launch site and (5) mission remarks is also presented.

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NASA NTRS1978

Materials processing in space program tasks

A list of active research tasks as of the end of 1978 of the Materials Processing in Space Program of the Office of Space and Terrestrial Applications, involving several NASA Centers and other organizations is reported. An overview of the program scope for managers and scientists in industry, university and government communities is provided. The program, its history, strategy and overall goal; the organizational structures and people involved; and each research task are described. Tasks are categorized by ground based research according to four process areas. Cross references to the performing organizations and principal investigators are provided.

Mckannan, E. C.↗
NASA NTRS1979

Probabilistic analysis of air carrier accidents

In order to estimate the potential risks due to carbon fibers (CF) released from aircraft accidents, it was necessary to quantify the probability of an accident or incident at a major hub airport. This probability was contingent upon various conditions surrounding the incident including the phase of operation, aircraft type, and the weather conditions. The type of accident predicted was categorized according to its location relative to the runway and the severity of damage sustained. The methodology utilized to estimate the probability of a specific type of accident is outlined and the various models that were developed in the course of this work are described.

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NASA NTRS1978

The 1990 direct support infrastructure

The airport and cargo terminal were individually analyzed in depth as the principal direct infrastructure components having cross impacts with aircraft carrying cargo. Containerization was also addressed in depth as an infrastructure component since it categorically is linked with and cross impacted by the aircraft, the cargo terminal, the surface transport system, the shipper and consignee, and the actual cargo being moved.

Source record↗
NASA NTRS1978

A critical evaluation of the minimization techniques as applied to nonlinear structural analyses

This paper identifies the potential for unconstrained minimization algorithms of mathematical programming to be cost-effective with other conventional techniques of transient nonlinear structural analysis. With this in mind the authors have attempted to critically evaluate a few of the most commonly used algorithms for their effectiveness in solving structural problems involving geometric and material nonlinearities. The algorithms have been categorized as being zeroth order, first order and second order depending upon the order of the derivative of the function called for by the algorithm. The sensitivity of these algorithms to the accuracy of derivatives derived on the basis of finite difference operations clearly suggest using analytically derived derivatives to obtain better control on the number of minimizations required for convergence to the exact solution.

Kamat, M. P.↗
NASA NTRS1978

On-board compensation for temporal changes in pushbroom scanner detector arrays

The design and operation of pushbroom and mechanical scanners are reviewed in order to determine differences in data preprocessing. Data preprocessing is categorized into spatial registration and radiometric corrections, as well as into systematic versus nonsystematic corrections. The category of nonsystematic radiometric errors due to temporal changes in detector array properties is emphasized as a subject of special interest and a challenging problem for onboard data preprocessing. Concepts for onboard compensation of temporal changes are presented. In particular one concept which uses dark current as an indicator of temperature change for determining gain and offset corrections is shown to have a number of advantages.

Jobson, D. J.↗
NASA NTRS1978

Encapsulant materials for $2/watt terrestrial photovoltaic arrays

Materials properties, cost data, and strawman designs are presented relative to materials for $2/watt terrestrial photovoltaic arrays to meet LSA Project cost goals for 1982. It is shown that encapsulation materials can be categorized in six basic elements: top covers, super-strates, pottants, adhesives, substrates, and bottom covers. The roles of the six basic encapsulant material elements in the encapsulant system are discussed and candidate materials presented.

Maxwell, H.↗
NASA NTRS1979

Landsat analysis of lake quality

The trophic status of a number of inland lakes in Wisconsin has been assessed. The feasibility of using both photographic and digital representations of Landsat imagery was investigated during the lake classification project. The result of the investigation has been a semi-automatic data acquisition and handling system which, in conjunction with an analytical categorization scheme, can be used to classify all the significant lakes in the state.

Scarpace, F. L.↗
NASA NTRS1979

On the size of the cometary tail magnetic field

Ershkovich's (1978) criticism of previous arguments in favor of magnetic fields of approximately 100 gammas in cometary plasma tails are shown to be unjustified. It is argued that the folding velocity of tail streamers indicates a substantial tail magnetic field and that much of Ershkovich's disagreement stems from the choice of completely different models for a comet's plasma tail. It is concluded that the use of growth rates or phase-velocity information obtained from a dispersion relation to interpret large-amplitude disturbances, such as those in comet tails, is categorically incorrect.

Mendis, D. A.↗
NASA NTRS1978

Environmental assessment of the proposed nonelectric application of geothermal resources at Desert Hot Springs, California

The paper presents an environmental analysis performed in evaluating various proposed geothermal demonstration projects at Desert Hot Springs. These are categorized in two ways: (1) indirect, or (2) direct uses. Among the former are greenhouses, industrial complexes, and car washes. The latter include aquaculture, a cascaded agribusiness system, and a mobile home park. Major categories of environmental impact covered are: (1) site, (2) construction of projects, and (3) the use of the geothermal source. Attention is also given to the disposal of the geothermal fluid after use. Finally, it is concluded that there are no major problems forseen for each project, and future objectives are discussed.

Rosenberg, L.↗
NASA NTRS1980

Siting solar thermal power experiments

The Small Community Solar Thermal Power Experiment will test a point-focusing, distributed receiver system in a small community, electric utility application. Site planning is becoming increasingly important for solar experiments as well as all kinds of development due to increased competition for desirable sites and increased complexity of regulatory requirements. Siting issues can be categorized as: (1) resources and physical environmental at this site; (2) acquisition, permits and regulations; and (3) development requirements and costs. These issues are addressed with respect to the unique requirements of solar thermal power experiments.

Holbeck, H. J.↗
NASA NTRS1980

Unfulfilled technology needs in space power systems

Major power system technology development needs related to the solution of currently existing problems are defined. The identified problems were initially listed and categorized by technical area. They were then translated into terms of technology development requirements and consolidated where commonality was found. From these requirements, a set of ten specific recommendations for technology development was formulated.

Slifer, L. W., Jr.↗
NASA NTRS1979

Phase 1 of the near term hybrid passenger vehicles development program. Appendix A: Mission analysis and performance specification studies, volume 1

Applicable data was categorized and processed according to vehicle usage and trip parameters with consideration of payload (cargo, people, size) and driving cycles. A mission that maximizes the fuel potential savings for the total 1985 vehicle fleet was selected. Mission requirements that have a bearing on conventional and hybrid vehicle performance and characteristics were identified and formulated and a reference ICE vehicle was selected that meets or exceeds all requirements while maintaining within applicable constraints. Specifications for vehicle performance were established based on mission requirements, mission related vehicle characteristics, and fuel consumption.

Traversi, M.↗
NASA NTRS1979

Survey of MHD plant applications

Open-cycle MHD is one of the major R&D efforts in the Department of Energy's program to meet the national goal of reducing U.S. dependence on oil through increased utilization of coal. MHD offers an effective way to use coal to produce electric power at low cost in a highly efficient and environmentally acceptable manner. Open-cycle MHD plants are categorized by the MHD combustor oxidizer, its temperature and the method of preheat. The paper discusses MHD baseline plant design, open-cycle MHD plant in the Energy Conversion Alternatives Study (ECAS), early commercial MHD plants, conceptual studies of the engineering test facility, retrofit (addition of an MHD topping cycle to an existing steam plant), and other potential applications and concepts. Emphasis is placed on a survey of both completed and ongoing studies to define both commercial and pilot plant design, cost, and performance.

Lynch, J. J.↗
NASA NTRS1979

Temporal studies of compact galactic X-ray sources

Advances in X-ray astronomy due to temporal studies are discussed. Attention is given to X-ray temporal variability categorized into periodic, quasi-periodic, and chaotic. Approximately 95% of all known X-ray sources exhibit chaotic variability, in which there is no apparent pattern or periodicities. The orbits of seven binary X-ray sources are presented, along with empirical findings of neutron star masses. In addition, the interior structure of a supergiant star, HD 77581, is investigated by attempting to measure its apsidal motion. Graphs are provided for the power density spectrum of 4U 1626-67, GX301-2 Doppler delay data, and empirically determined error contours for the mass and radius of four companions stars in X-ray binary systems.

Rappaport, S.↗
NASA NTRS1980

A survey of Saturn orbiter transfer options

This paper is a description of recent work to categorize and enumerate the various options available for transfer from earth to Saturn orbit. The fundamental period of investigation is the 20-year synodic period of Jupiter and Saturn which permits a scenario of Jupiter gravity assist trajectories for various trip times. Against the background of the Jupiter swingby trajectories are compared a number of other options including Delta V-EGA and VEGA trajectories, direct earth-Saturn transfers, and solar and nuclear electric propulsion options. All are compared and contrasted in the context of expected launch vehicle capabilities and realistic transfer times.

Uphoff, C.↗
NASA NTRS1980

A technology development program for large space antennas

The design and application of the offset wrap rib and the maypole (hoop/column) antenna configurations are described. The NASA mission model that generically categorizes the classes of user requirements, as well as the methods used to determine critical technologies and requirements are discussed. Performance estimates for the mesh deployable antenna selected for development are presented.

Russell, R. A.↗
NASA NTRS1980

Studies of high latitude current systems using Magsat vector data

Disturbance fields caused by global external current systems are analyzed in order to gain an improved understanding of the phydical processes which control high latitude current systems and to increase the confidence level in the identification of internal field levels. The basic approach is to: (1) categorize the vector data by those physical parameters important for investigation of external current systems; (2) map the disturbances for appropriate conditions; (3) model the currents which might cause the mapped disturbances; and (4) correlate results with data from other sources. It is concluded that the Magsat data set appears to have remarkably high precision and quality and should permit major advances to be made in modeling current distribution at high latitudes in the ionosphere and magnetosphere.

Burrows, J. R.↗