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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

The NASA data systems standardization program - Rationale and scope

A simple, top level logical reference model of the NASA Space Transportation System's end-to-end data system is being developed which can identify the functions and services of the system. Each function or service may be mapped into specific physical subsystems, so that interface relationships are evident and 'standard' protocols may be identified for development. By means of this interface standardization, subsystems can be designed not only independently and in parallel, but with confidence that when the subsystems are aggregated, the end-to-end system will operate efficiently and at low cost. This standardization effort has thus far been principally directed toward space-to-ground communications links.

Smylie, R. E.↗
NASA NTRS1982

ACEE program rationale and implementation

The impact of the Aircraft Energy Efficiency program (ACEE) on commercial aviation is examined. In addition to the emphasis on air transport fuel efficiency, topics such as airline operating costs, air transport effects on U.S. trade, and fuel price forecasts are addressed. An overview of the program and its contribution to aviation technology is included.

Aiken, W. S., Jr.↗
NASA NTRS1984

The rationale and suggested approaches for research geosynchronous satellite measurements for severe storm and mesoscale investigations

The measurements from current and planned geosynchronous satellites provide quantitative estimates of temperature and moisture profiles, surface temperature, wind, cloud properties, and precipitation. A number of significant observation characteristics remain, they include: (1) temperature and moisture profiles in cloudy areas; (2) high vertical profile resolution; (3) definitive precipitation area mapping and precipitation rate estimates on the convective cloud scale; (4) winds from low level cloud motions at night; (5) the determination of convective cloud structure; and (6) high resolution surface temperature determination. Four major new observing capabilities are proposed to overcome these deficiencies: a microwave sounder/imager, a high resolution visible and infrared imager, a high spectral resolution infrared sounder, and a total ozone mapper. It is suggested that the four sensors are flown together and used to support major mesoscale and short range forecasting field experiments.

Shenk, W. E.↗
NASA NTRS1985

Rationale for an experimental test for flexible space structure attitude control

The problems of large flexible spacecraft control are characterized by the infinite bandwidth of structural vibrations, which cannot be accounted for in the dynamic design model. This may lead to instability even, if ideal control hardware is assumed, which can be concluded from preceding numerical investigations. Additional performance limitations are expected to occur due to hardware constraints. A laboratory experiment is proposed to investigate the key problems in more detail. The test setup requirements being defined by the idealized control system are extremely high demanding a high speed processor and special hardware component developments. The test element is a wire suspended plate being controlled by an array processor via high performance sensors and actuators. First tests on component level indicate the feasibility of the system presently being developed.

Lange, T.↗
NASA NTRS1984

Rationale for two phase polymer system microgravity separation experiments

The two-phase systems that result when aqueous solutions of dextran and poly(ethylene glycol) are mixed at concentrations above a few percent are discussed. They provide useful media for the partition and isolation of macromolecules and cell subpopulations. By manipulating their composition, separations based on a variety of molecular and surface properties are achieved, including membrane hydrophobic properties, cell surface charge, and membrane antigenicity. Work on the mechanism of cell partition shows there is a randomizing, nonthermal energy present which reduces separation resolution. This stochastic energy is probably associated with hydrodynamic interactions present during separation. Because such factors should be markedly reduced in microgravity, a series of shuttle experiments to indicate approaches to increasing the resolution of the procedure are planned.

Brooks, D. E.↗
NASA NTRS1985

Mission-oriented requirements for updating MIL-H-8501: Calspan proposed structure and rationale

This report documents the effort by Arvin/Calspan Corporation to formulate a revision of MIL-H-8501A in terms of Mission-Oriented Flying Qualities Requirements for Military Rotorcraft. Emphasis is placed on development of a specification structure which will permit addressing Operational Missions and Flight Phases, Flight Regions, Classification of Required Operational Capability, Categorization of Flight Phases, and Levels of Flying Qualities. A number of definitions is established to permit addressing the rotorcraft state, flight envelopes, environments, and the conditions under which degraded flying qualities are permitted. Tentative requirements are drafted for Required Operational Capability Class 1. Also included is a Background Information and Users Guide for the draft specification structure proposed for the MIL-H-8501A revision. The report also contains a discussion of critical data gaps and attempts to prioritize these data gaps and to suggest experiments that should be performed to generate data needed to support formulation of quantitative design criteria for the additional Operational Capability Classes 2, 3, and 4.

Chalk, C. R.↗
NASA NTRS1985

Rationale for a GRAVSAT-MAGSAT mission: A perspective on the problem of external/internal transient field effects

The Earth's magnetic field at MAGSAT altitudes not only has contributions from the Earth's core and static magnetization in the lithosphere, but also from external electric current systems in the ionosphere and magnetosphere, along with induced electric currents flowing in the conducting earth. Hermance assessed these last two contributions; the external time-varying fields and their associated internal counter-parts which are electromagnetically induced. It is readily recognized that during periods of magnetic disturbance, external currents often contribute from 10's to 100's of nanoteslas (gammas) to observations of the Earth's field. Since static anomalies from lithospheric magnetization are of this same magnitude or less, these external source fields must be taken into account when attempting to delineate gross structural features in the crust.

Hermance, J. F.↗
NASA NTRS1987

The rationale for an aeroassist flight experiment

The states of several technologies are reviewed which are critical to the design of an aeroassisted orbital transfer vehicle. In these technologies, advancements are needed which hinge on obtaining new flight data. While some of the work can be done with the wind tunnel and computational disciplines, much of the required new data are tied to finite chemical reaction rates, possible thermal nonequilibrium, high flow enthalpy, and strong viscous effects. Because these effects cannot be modeled adequately in ground-based facilities, computational methods lack adequate verification to allow committing to the design of an aeroassist vehicle. Thus a new flight experiment is being planned by NASA to gather the required data. The flight experiment and associated instrumentation which NASA is proposing is discussed briefly.

Jones, Jim J.↗
NASA NTRS1987

Rationale for an integrated moon/Mars exploration program

Although it is possible to design manned missions to Mars that do not involve prior lunar missions, a strategy that includes development of a lunar base before or concurrent with the Mars program offers potential benefits from space infrastructure development, space operations experience, and utilization of lunar materials for propulsion. Common utilization of infrastructure elements (e.g., Orbital Transfer Vehicles, Space Operation Center modules) is emphasized in this approach. Mass flows through a low Earth orbit Space Station change in quantity and in proportion of propellant to hardware as the infrastructure develops.

Duke, Michael B.↗
NASA NTRS1988

Kidney cell electrophoresis in space flight: Rationale, methods, results and flow cytometry applications

Cultures of human embryonic kidney cells consistently contain an electrophoretically separable subpopulation of cells that produce high levels of urokinase and have an electrophoretic mobility about 85 percent as high as that of the most mobile human embryonic kidney cells. This subpopulation is rich in large epithelioid cells that have relatively little internal structure. When resolution and throughput are adequate, free fluid electrophoresis can be used to isolate a broad band of low mobility cells which also produces high levels of plasminogen activators (PAs). In the course of performing this, it was discovered that all electrophoretic subpopulations of cultured human embryonic kidney cells produce some PAs and that separate subpopulations produce high quantities of different types of PA's. This information and the development of sensitive assays for this project have provided new insights into cell secretion mechanisms related to fibrinolysis. These advances would probably not have been made without the NASA program to explore fundamental questions of free fluid electrophoresis in space.

Todd, P.↗
NASA NTRS1989

Rationale for Mars Rover/Sampler Return mission

A Mars Rover/Sample Return (MRSR) mission is currently being studied for the late 1990's. The objectives of the mission are to better understand the origin and evolution of Mars, to search for evidence of former life, and to improve the knowledge of the Martian environment in preparation for subsequent human exploration. Having formed in a different part of the Solar System from Earth, Mars will provide clues that will better enable the discrimination between conflicting theories of Solar System formations. Mars is also a natural laboratory on which a wide range of geologic and meteorological processes have operated under conditions very different from those on Earth. Samples are needed so that the full range of analytical techniques available here on Earth can be applied to the study of these issues. The rover provides the mobility needed to access different materials, and can be equipped with an analytical capability so that the planet can be sampled intelligently. The rover will also provide the means of exploring the planet on a human scale and performing a wide range of in situ measurements at different locations. Different mission scenarios are currently being studied with the goal of achieveing sample return before the end of the century.

Carr, Michael H.↗
NASA NTRS1989

Stratospheric Observatory for Infrared Astronomy (SOFIA) science rationale

SOFIA, a proposed 3-meter class telescope in a Boeing 747 aircraft, would have the ability to make astronomical observations over a wavelength range from 0.3 microns to 1.6mm. Relative to the KAO (Kuiper Airborne Observatory) the larger telescope on SOFIA would provide a factor of 10 improvement in sensitivity for compact sources and a factor of 3 improvement in (diffraction-limited) angular resolution at wavelengths beyond 30 microns. In addition, SOFIA will retain the major features of the KAO which have made the airborne astronomy program so successful. Among these are continuous in-flight access to focal plane instruments while flying at or above 41,000 ft altitude; pointing stability of 0.2 arcseconds; and mobility and scheduling flexibility to accommodate targets of opportunity such as comets, eclipses, occultations, and novae.

Davidson, Jacqueline A.↗
NASA NTRS1989

A rationale for atmospheric monitoring on Space Station Freedom

The atmosphere monitoring needs for the Space Station Freedom are identified by examining the monitoring requirements for supplied breathing air in confined spaces, as in the case of submarines and the Shuttle. Some other factors influencing the monitoring requirements for Space Station Freedom are also identified. These include: the experience of past missions and ground based tests; the proposed experimental and manufacturing processes and their hazards; and limitations of the life support systems.

Casserly, Dennis M.↗
NASA NTRS1990

Rationale and requirements for lunar exploration

The moon has had a complex and geologically fascinating history. It is a natural laboratory in which to study planetary processes and is readily accessible, only 2.5 days away. The moon is the only planetary object from which there are samples of known geologic context, and its history is understood well enough to permit the posing and answering of sophisticated scientific questions. The moon also preserves information about the earth's early history and cratering record, and about the sun's history. To retrieve all this information, it is necessary to return to the moon and study it from orbit, establish surface geophysical networks, obtain reconnaissance samples, and perform field work. These ventures will require development of interesting technological systems, such as a robotic field geologist, automated roving vehicles (both pressurized for humans and unpressurized for robotic devices), a host of sampling tools, automated sample-return spacecraft, and all of the associated navigation, communication, and power systems.

Spudis, Paul D.↗
NASA NTRS1991

Scientific Rationale and Requirements for a Global Seismic Network on Mars

Following a brief overview of the mission concepts for a Mars Global Network Mission as of the time of the workshop, we present the principal scientific objectives to be achieved by a Mars seismic network. We review the lessons for extraterrestrial seismology gained from experience to date on the Moon and on Mars. An important unknown on Mars is the expected rate of seismicity, but theoretical expectations and extrapolation from lunar experience both support the view that seismicity rates, wave propagation characteristics, and signal-to-noise ratios are favorable to the collection of a scientifically rich dataset during the multiyear operation of a global seismic experiment. We discuss how particular types of seismic waves will provide the most useful information to address each of the scientific objectives, and this discussion provides the basis for a strategy for station siting. Finally, we define the necessary technical requirements for the seismic stations.

Solomon, Sean C.↗
NASA NTRS1991

A design rationale for NASA TileWorld

Automated systems that can operate in unrestricted real-world domains are still well beyond current computational capabilities. This paper argues that isolating essential problem characteristics found in real-world domains allows for a careful study of how particular control systems operate. By isolating essential problem characteristics and studying their impact on autonomous system performance, we should be able to more quickly deliver systems for practical real-world problems. For our research on planning, scheduling, and control, we have selected three particular domain attributes to study: exogenous events, uncertain action outcome, and metric time. We are not suggesting that studies of these attributes in isolation are sufficient to guarantee the obvious goals of good methodology, brilliant architectures, or first-class results; however, we are suggesting that such isolation facilitates the achievement of these goals. To study these attributes, we have developed the NASA TileWorld. We describe the NASA TileWorld simulator in general terms, present an example NASA TileWorld problem, and discuss some of our motivations and concerns for NASA TileWorld.

Philips, Andrew B.↗
NASA NTRS1992

The rationale for fundamental research in space biology - Introduction and background

An overview is presented of the concept and development of SSF and the unique opportunities offered by SSF to take advantage of the greater space, the increased power, and especially the long duration of the station for a cascade of innovative experiments in fundamental science. It is emphasized that this space environment will provide new dimensions for approaching some of the most challenging problems still facing modern biology.

Halstead, T. W.↗