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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 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

A Voyager attitude control perspective on fault tolerant systems

In current spacecraft design, a trend can be observed to achieve greater fault tolerance through the application of on-board software dedicated to detecting and isolating failures. Whether fault tolerance through software can meet the desired objectives depends on very careful consideration and control of the system in which the software is imbedded. The considered investigation has the objective to provide some of the insight needed for the required analysis of the system. A description is given of the techniques which have been developed in this connection during the development of the Voyager spacecraft. The Voyager Galileo Attitude and Articulation Control Subsystem (AACS) fault tolerant design is discussed to emphasize basic lessons learned from this experience. The central driver of hardware redundancy implementation on Voyager was known as the 'single point failure criterion'.

Rasmussen, R. D.↗
NASA NTRS1981

Tropospheric chemistry - A global perspective

Processes that affect the concentration of tropospheric OH are considered, taking into account linkages between the chemistry of OH and the chemistry of H, HO2, and H2O2. A review is presented of observational data of special relevance to OH, notably the distributions of CO, CH4, O3, H2O, HNO3, NO, and NO2. Most of the results presented in connection with the description of the model were obtained by solving time-dependent continuity equations. Rates for photolytic processes were allowed to vary diurnally with insolation. It is found that a well-calibrated and reliable model for OH places important constraints on global budgets for a variety of gases including CH4, H2, and CH3Cl in addition to CO. Accurate measurements of species such as CH3CCl3 can provide valuable checks on global models that must integrate over a variety of atmospheric conditions. However, emission rates for the relevant gases must be adequately quantified.

Logan, J. A.↗
NASA NTRS1981

The Space Shuttle in perspective

Commercial aspects of the Space Shuttle are examined, with attention given to charges to users, schedule of launches and reimbursement, kinds of payload and their selection, NASA authority, space allocation, and risk, liability, and insurance. It is concluded that insurance to reduce the risk, incentives that NASA is willing to make available to U.S. industry, and the demonstrated willingness of industry and the financial community to invest their funds in space ventures indicate that the new Shuttle capabilities will exponentially increase commercial activities in space during the 1980s.

Hosenball, S. N.↗
NASA NTRS1981

Technical Communication: Perspectives for the Eighties, Part 1. Proceedings of the Technical Communications Sessions at the 32Nd Annual Meeting of the Conference on College Composition and Communication

Proceeding of the technical communication sessions at the 32nd annual meeting of the Conference on College Composition and Communication held in Dallas, Texas, March 26-28, 1981 are summarized. The proceeding suggest that technical communication has become an important subfield and is becoming an intrinsic part of many undergraduate curricula. Technical communication as a separate discipline, however, is relatively new. For that reason, proceedings that can make current research available as quickly as possible are suggested for preparation. The following topics were addressed: (1) a history and definition of technical writing, (2) the case method is technical communication (3) teaching technical writing (4) oral communication and rhetorical theory, and (5) new approaches in and practical applications of technical writing.

Mathes, J. C.↗
NASA NTRS1981

Clinical report writing: Process and perspective

Clinical report writing in psychology and psychiatry is addressed. Audience/use analysis and the basic procedures of information gathering, diagnosis, and prognosis are described. Two interlinking processes are involved: the process of creation and the process of communication. Techniques for good report writing are presented.

Ewald, H. R.↗
NASA NTRS1981

Technical communication. Perspectives for the Eighties, part 2

The importance of technical writing as a separate discipline is suggested. Some specific areas addressed were: technical writing skills industry needs, definitions of technical writing, the hows and whys of inhouse writing, and the nature of the composing process in technical comunication.

Mathes, J. C.↗
NASA NTRS1982

The aerospace technology laboratory (a perspective, then and now)

The physical changes that have taken place in aerospace facilities since the Wright brothers' accomplishment 78 years ago are highlighted. For illustrative purposes some of the technical facilities and operations of the NASA Lewis Research Center are described. These simulation facilities were designed to support research and technology studies in aerospace propulsion.

Connors, J. F.↗
NASA NTRS1982

Historical perspectives on thermostructural research at the NACA Langley Aeronautical Laboratory from 1948 to 1958

Research on structural problems associated with aerodynamic heating, conducted by the National Advisory Committee for Aeronautics (NACA) during its last decade are described. The text of a special presentation given at the NASA Symposium on Computational Aspects of Heat Transfer in Structure is presented. Some early thermostructural research activities using charts is also discussed. The prinicipal message of the paper is that although vehicle oriented research programs speed development of new technology for specific missions, too much effort may be expended on developing technology which is never used because a vehicle is never built. A healthy research program must provide freedom to explore new ideas that have no obvious applications at the time to generate the technology that makes important, unanticipated flight or vehicle opportunities possible.

Heldenfels, R. R.↗
NASA NTRS1981

Mission perspectives

Handling the Martian samples by requiring that they be subjected to a complex protocol designed to detect life, which, if present, will then be assessed for its effects on terrestrial life forms is addressed. Sample testing must be performed within facilities that ensure that such Martian organisms cannot be accidentally introduced to Earth's biosphere during the assessment process. An Orbiting Quarantine Facility (OQF) designed to permit the detection and characterization of Martian life forms, while affording the Earth and its inhabitants the maximum level of protection, is analyzed and described.

Source record↗
NASA NTRS1981

The LANDSAT system operated in Brazil by CNPq/INPE - results obtained in the area of mapping and future perspectives

The LANDSAT system, operated in the country by CNPg/INPE since 1973, systematically acquires, produces, and distributes both multispectral and panchromatic images obtained through remote sensing satellites to thousands of researchers and technicians involved in the natural resources survey. To cooperate in the solution of national problems, CNPq/INPE is developing efforts in the area of manipulation of those images with the objective of making them useful as planimetric bases for the simple revision of already published maps or for its utilization as basic material in regions not yet reliability mapped. The results obtained from performed tests are presented and the existing limitations are discussed. The new system purchased to handle data from the next series of LANDSAT as well as from MAPSAT and SPOT which will be in operation within the 80's decade, and are designed not only for natural resources survey but also for the solution of cartographic problems.

Dejesusparada, N.↗
NASA NTRS1981

Gamma ray astronomy in perspective

A brief overview of the development of gamma ray astronomy is presented. Gamma ray telescopes and other optical measuring instruments are highlighted. Emphasis is placed on findings that were unobtainable before gamma ray astronomy. Information on evolution of the solar system, the relationship of the solar system to the galaxy, and the composition of interstellar matter is discussed.

Source record↗
NASA NTRS1981

Technology transfer program: Perspective

Most of NASA's technology transfer activities are in the area of land use (development, suitability, and planning); forestry (including wildlife and range and vegetation inventories) agriculture related activities; and water resources. The technology dissemination function is exercised through three regional applications centers which are involved in 91 applications projects within 22 states. In addition there are approximately eight application system verification transfer (ASVT) projects, 21 university applications branches, institutionalized liason activities with public interest groups, and user requirements activities. As the result of budget cuts, the ASVT and user requirements and awareness programs are to be phased out at the end of FY81. The university applications programs are to be phased down and terminated by 1985. NASA will continue to work with the user more in an R & D and an applications development capacity, and not in a national scale or administrative way.

Toyshov, A. J.↗
NASA NTRS1980

SPS structures and control: A perspective

The characteristics and design requirements for the structure and control systems for a solar power satellite were evaluated. A simplistic, indicative analysis on a representative configuration was developed. Representative configuration masses and dimensions are given in convenient approximate magnitudes. The significance of structure control interaction and the significance of stiffness to the minimization of dynamic energy was demonstrated. It was found that the thermal environment for the SPS was dominated by solar radiation and waste heat rejection by the antenna. A more in-depth assessment of the control system design and associated system performance is still needed, specifically the inter-relatonships between control sensors, actuators, and structural response.

Ried, R. C.↗
NASA NTRS1980

SPS program review transportation perspective

The delivery of cargo and space workers to the SPS construction site requires the development of two different systems, one to handle large cargo deliveries and a smaller system to accommodate crew. The overall scenario of the transportation system is shown. Eight major elements comprise the transportation system: personnel launch vehicle (PLV) or shuttle; personnel orbital transfer vehicle (POTV); the heavy lift launch vehicle (HLLV); the electric orbital transfer vehicle (EOTV); intra orbit transfer vehicle (IOTV); LEO support facility; GEO support facility and a shuttle derived HLLV (SDHLLV) for supporting the early SPS Demonstration Program. The HLLV and EOTV represent the cargo carriers while the PLV and POTV represent the people carriers. The IOTV is utilized to ferry people and cargo modules over short distances in the vicinity of its station.

Wales, W. W., Jr.↗
NASA NTRS1980

Power transmission and reception. An overview and perspective

Systems definition and assessment of the microwave power transmission and reception (PTAR) system for the solar power satellite are surveyed. Five different options are discussed and the separate antenna concept using the linear beam klystron to convert from dc to RF energy is described in detail.

Dietz, R. H.↗
NASA NTRS1980

SPS construction perspective. Summary

Projections concerning the general construction requirements for a solar power satellite (SPS) are summarized. It is recognized that the ability to construct an SPS must be developed through an evolutionary process. This process would begin with shuttle operations and when construction timelines exceed the shuttle capability, small manned bases in low Earth orbit (LEO) would be used. The influence of construction methods on design, assembly bases, and crew considerations are addressed.

Benson, H.↗
NASA NTRS1982

Helicopter simulation technology: An Ames Research Center perspective

The total experience for evidence regarding the levels of motion and visual cueing fidelity required for handling-qualities research in ground-based simulators is reviewed. Positive contributions of cockpit motion were identified, but much remains to be learned regarding the sensitivities of individual control modes to cueing attenuation. A firmer understanding of the pilot's utilization of visual and motion cues is the key to more efficient use of simulation in helicopter control-systems research.

Bray, R. S.↗
NASA NTRS1982

Historical perspectives on thermostructural research at the NACA Langley Aeronautical Laboratory from 1948 to 1958

Some of the early research on structural problems produced by aerodynamic heating, conducted at the Langley Aeronautical Laboratory of the National Advisory Committee for Aeronautics from 1948 to 1958 is described. That was the last decade of the NACA; in 1958 NACA became the nucleus of NASA. The NACA initially contracted for research but was aware that a well-equipped and suitably staffed laboratory was required to fulfill its obligations. Langley was established in 1920; the other listed were added during the NACA expansion in the World War II years. Some specific research activities are described, starting with calculation of the temperature of the structure.

Heldenfels, R. R.↗