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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 595 records · Page 33
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Instrument intercomparisons and assessments

Over the past few years, several field campaigns were devoted to the goal of assessing instrument reliability, as opposed to solely obtaining data to answer a geophysical question. Some examples of the formal instrument intercomparisons that have occurred in the past decade and those that are planned for the very near future are listed chronologically. Balloon-borne techniques and instruments that address the height profiles of the trace species in the lower stratosphere are emphasized. Beginning with the most extensively studied trace constituent, the approach taken and the results obtained, are described. The current status of the measurement capabilities are summarized, and the needs for future intercomparisons and assessments are listed.

Albritton, D. L.↗
NASA NTRS1985

Some comparisons of US and USSR aircraft design developments

A review is given of the design and development of some U.S. and U.S.S.R. aircraft. The emphasis is on the historical development of large aircraft - civil and military transports and bombers. Design trends are somewhat similar for the two countries and indications are that some fundamental characteristics are dictated more by ideological differences rather than technological differences. A brief description is given in a more or less chronological order of the major bomber aircraft, major civil and military transport aircraft, and the development of the air transport systems.

Spearman, M. L.↗
NASA NTRS1986

Formation of the sun and its planets

Aspects of star formation are considered, taking into account those observations and models which have a relation to the formation of the solar system. Attention is given to the galactic structure, the stellar properties, planetary indications, interstellar clouds, observations of forming stars, the conditions for cloud collapse, models of star formation, the modeling of secondary features, and aspects of dynamical evolution. Aspects of cosmochemistry are also explored. Questions of chronology are discussed along with nuclide variations, chemical variations among chondritic meteorites, and chemical variations among differentiated objects. A description of planet formation is provided, taking into consideration, gas-dust interaction, sun and accretion disk dynamics, planetesimal swarms, planet-disk interactions, planetary systems, terrestrial planet formation, and gaseous protoplanet contraction.

Kaula, W. M.↗
NASA NTRS1986

A discussion of isotopic systematics and mineral zoning in the shergottites - Evidence for a 180 m.y. igneous crystallization age

The chronologies of the Shergotty, Zagami, ALHA 77005, and EETA 79001 meteorites were reexamined on the basis of shergottites' petrography and mineral chemistry data. Among the various isochrons, the concordant Rb-Sr (about 180 Myr) and U-Th-Pb (about 190 Myr) internal isochrons are interpreted as representing the time of igneous crystallization, while the Rb-Sr, Sm-Nd, and Pb-Pb whole-rock isochrons are interpreted as mixing lines, and are reasonably attributed to igneous processes such as wall-rock assimilation and magma mixing. If the approximated age of less than 200 Myr is correct, the shergottites represent the youngest known extraterrestrial basalts. This conclusion supports the hypothesis that the SNC meteorites are samples of Mars.

Jones, J. H.↗
NASA NTRS1986

Measurement of H2O and other trace gases in the stratosphere using a high resolution far-infrared spectrometer at 28 KM

The highlights of the stratospheric program were reviewed for the past 2.5 years. The major efforts were analysis of the data from the BIC-2 campaign, and the building or new instrumentation to replace that lost at the end of BIC-2. For clarity, the review will be done by topic, rather than chronologically: construction of the initial far-infrared spectrometer, balloon slight program, laboratory measurement, data analysis, and duplicate stabilized platform.

Traub, W. A.↗
NASA NTRS1986

Space plasma research

Four basic areas were covered: development of analysis techniques and software and numerical simulations; data analysis and interpretation; spacecraft sheath studies; and laboratory studies. The important details were documented in terms of either appropriate software documentation or publication in referred publication, conference proceeding and technical reports. The major accomplishments are summarized, followed by a chronological listing of the publications and presentations which resulted from the research.

Comfort, R. H.↗
NASA NTRS1986

Wind tunnel wall interference in V/STOL and high lift testing: A selected, annotated bibliography

This bibliography, with abstracts, consists of 260 citations of interest to persons involved in correcting aerodynamic data, from high lift or V/STOL type configurations, for the interference arising from the wind tunnel test section walls. It provides references which may be useful in correcting high lift data from wind tunnel to free air conditions. References are included which deal with the simulation of ground effect, since it could be viewed as having interference from three tunnel walls. The references could be used to design tests from the standpoint of model size and ground effect simulation, or to determine the available testing envelope with consideration of the problem of flow breakdown. The arrangement of the citations is chronological by date of publication in the case of reports or books, and by date of presentation in the case of papers. Included are some documents of historical interest in the development of high lift testing techniques and wall interference correction methods. Subject, corporate source, and author indices, by citation numbers, have been provided to assist the users. The appendix includes citations of some books and documents which may not deal directly with high lift or V/STOL wall interference, but include additional information which may be helpful.

Tuttle, M. H.↗
NASA NTRS1987

Compendium of NASA Langley reports on hypersonic aerodynamics

Reference is made to papers published by the Langley Research Center in various areas of hypersonic aerodynamics for the period 1950 to 1986. The research work was performed either in-house by the Center staff or by other personnel supported entirely or in part by grants or contracts. Abstracts have been included with the references when available. The references are listed chronologically and are grouped under the following general headings: (1) Aerodynamic Measurements - Single Shapes; (2) Aerodynamic Measurements - Configurations; (3) Aero-Heating; (4) Configuration Studies; (5) Propulsion Integration Experiment; (6) Propulsion Integration - Study; (7) Analysis Methods; (8) Test Techniques; and (9) Airframe Active Cooling Systems.

Sabo, Frances E.↗
NASA NTRS1986

Site selection for manned Mars landings: A geological perspective

Issues relating to the selection of initial landing sites for manned Mars missions are discussed from a geological viewpoint. The two prime objectives for initial manned exploration should be the youngest unambiguous lava flows (to tie down the late end of the cratering history curve for Mars) and old highland crust, which is best sampled and studied through the use of large impact basins as natural, planetary drill-holes. Exploration of these two sites will provide data on Martian chronology, volcanism, impact processes and gross chemical structure that will enable a first-order global synthesis through integration of these results with the global remote-sensing data already in hand from Viking and that to be provided by the Mars Observer Mission.

Spudis, Paul D.↗
NASA NTRS1987

Comments on the tectonism of Venus

Preliminary tectonic mapping of Venus from Venera 15/16 images shows unquestionable evidence of at least limited horizontal tectonism. The majority of tectonic features on Venus have no relation to topography. In fact, many axes of disruption interconnect, and cross sharp topographic boundaries at large angles, thereby discounting gravity as the driving force. Compressional zones (CZ's), unlike Extensional zones (EZ's), tend to be discontinuous, and, whereas EZ's cross tectonic and topographic boundaries at various angles, many CZ's on Venus are subparallel to these boundaries. Strike-like faulting is curiously lacking from the mapping, possible due to the steep incidence angle of the radar, which is far from optimal for detecting faults of small throw. A chronology of horizontal crustal movements, and hence the analysis of Venus' thermal development, is large dependent on understanding the crater form features. Regardless of their uncertain origin, the craters still could hold the answer to whether, and to what extent, crustal shuffling is occurring on Venus.

Kozak, R. C.↗
NASA NTRS1987

Characterization and hardware modification of linear momentum exchange devices

A sequence of modifications were made on the TRW Linear Momentum Exchange Devices (LMEDs) which were supplied for a joint MSFC/Air Force Wright Aeronautical Laboratory (AFWAL) control venture called Vibrational Control of Space Structures (VCOSS)-II. The modifications were necessary to alleviate and assuage the LMED nonlinearities. Extensive discussion of the LMED modification are presented along with the test plan, test results and conclusions. In addition, a chronology of events, relative to the LMED changes, is given.

Edgemon, George D.↗
NASA NTRS1987

SWITCH user's manual

The planning program, SWITCH, and its surrounding changed-goal-replanning program, Runaround, are described. The evolution of SWITCH and Runaround from an earlier planner, DEVISER, is recounted. SWITCH's plan representation, and its process of building a plan by backward chaining with strict chronological backtracking, are described. A guide for writing knowledge base files is provided, as are narrative guides for installing the program, running it, and interacting with it while it is running. Some utility functions are documented. For the sake of completeness, a narrative guide to the experimental discrepancy-replanning feature is provided. Appendices contain knowledge base files for a blocksworld domain, and a DRIBBLE file illustrating the output from, and user interaction with, the program in that domain.

Source record↗
NASA NTRS1986

Atlas of Comet Halley 1910 II

With the impending return of Halley's Comet in 1986, a major effort began to collect the material obtained at its last appearance in 1910. This material displays the evolving coma and tail phenomena, and is useful for comparison with the present quantitative studies of spectroscopic and structural phenomena. Images in the atlas are arranged in chronological order by day. Days that have multiple images with varying scale are arranged in two sequences. Photographs showing tail phenomena are first, followed by photographs obtained with longer focus instruments showing the head or near-nuclear region. Drawings of Comet Halley, made from visual observations in 1835 and 1910, also are included.

Bertram Donn↗
NASA NTRS1986

Preliminary conclusions of the Royal Society and Academia Sinica 1985 geotraverse of Tibet

The preliminary fieldwork results of a geological traverse across the high Tibetan plateau during June and July 1985 are presented. An effort was made to investigate the origin and chronology of successive collisions of continental fragments with Laurasian or Gondwanian provenance, and to ascertain how the crust of Tibet was thickened. The traverse followed the 1150-km-long Lhasa-Golmud highway; the pre-Cenzoic geology of the region is described from north to south.

Chang, Chengfa↗
NASA NTRS1986

Turbulence modeling

A survey designed to provide an introduction to the subject of turbulence modeling, and to explain the need for such models is given. The subject is developed along chronological lines since this provides a logical development plan and also because it then moves from relatively simple phenomenological models through more complicated procedures and ultimately to the subject of large-eddy simulation.

Murphy, J. D.↗
NASA NTRS1988

Testing Parabolic-Dish Concentrators

Report describes test equipment and tests at Parabolic Dish Test Site at Edwards Air Force Base in California. Site established in 1978 for testing point-focusing solar concentrators operating at temperatures above 600 degree F. Used for six years to evaluate parabolic-dish concentrators, receivers, power-conversion units, and solar/fossil-fuel hybrid units. Report describes evolution of test program at site, lists experiments conducted there in chronological order, and summarizes experimental data.

Selcuk, M. Kudret↗
NASA NTRS1986

Communication satellite technology trends

A chronology of space-Earth interconnectivity is presented. The Advanced Communications Technology Satellite (ACTS) system, Land Mobile Satellite, space-Earth antennas, impact of antenna size on coverage, intersatellite links are outlined. This presentation is represented by graphs and charts only.

Cuccia, Louis↗
NASA NTRS1987

A monograph of the National Space Transportation System Office (NSTSO) integration activities conducted at the NASA Lyndon B. Johnson Space Center for the EASE/ACCESS payload flown on STS 61-B

The integration process of activities conducted at the NASA Lyndon B. Johnson Space Center (JSC) for the Experimental Assembly of Structures in Extravehicular activity (EASE)/Assembly Concept for Construction of Erectable Space Structures (ACCESS) payload is provided as a subset to the standard payload integration process used by the NASA Space Transportation System (STS) to fly payloads on the Space Shuttle. The EASE/ACCESS payload integration activities are chronologically reviewed beginning with the initiation of the flight manifesting and integration process. The development and documentation of the EASE/ACCESS integration requirements are also discussed along with the implementation of the mission integration activities and the engineering assessments supporting the flight integration process. In addition, the STS management support organizations, the payload safety process leading to the STS 61-B flight certification, and the overall EASE/ACCESS integration schedule are presented.

Chassay, Charles↗