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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 1,135 records · Page 63
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Recursive identification and tracking of parameters for linear and non-linear multivariable systems

The problem of identifying constant and variable parameters in multi-input, multi-output, linear and nonlinear systems is considered, using the maximum likelihood approach. An iterative algorithm, leading to recursive identification and tracking of the unknown parameters and the noise covariance matrix, is developed. Agile tracking and accurate and unbiased identified parameters are obtained. Necessary conditions for a globally asymptotically stable identification process are provided; the conditions proved to be useful and efficient. Among different cases studied, the stability derivatives of an aircraft were identified and some of the results are shown as examples.

Sidar, M.↗
NASA NTRS1976

Meteorological regimes for the classification of aerospace air quality predictions for NASA-Kennedy Space Center

A method is described for developing a statistical air quality assessment for the launch of an aerospace vehicle from the Kennedy Space Center in terms of existing climatological data sets. The procedure can be refined as developing meteorological conditions are identified for use with the NASA-Marshall Space Flight Center Rocket Exhaust Effluent Diffusion (REED) description. Classical climatological regimes for the long range analysis can be narrowed as the synoptic and mesoscale structure is identified. Only broad synoptic regimes are identified at this stage of analysis. As the statistical data matrix is developed, synoptic regimes will be refined in terms of the resulting eigenvectors as applicable to aerospace air quality predictions.

Stephens, J. B.↗
NASA NTRS1976

Development of a multi-disciplinary ERTS user program in the state of Ohio

The author has identified the following significant results. A preliminary comparison of the land use maps derived from high altitude photography and imagery generated from land use CCT's shows considerable correlation of data. Most land use features are best identified on LANDSAT data taken over a full year, showing the effects of the four seasons. It appears that the most cost effective and timely way of providing land use data is to use LANDSAT data for identifying 75 to 90 percent of land use categories, using temporal data. For surface mining, close examination of LANDSAT, Skylab, and aircraft data covering the same area where linears were found seems to indicate that the type of resolution characteristic of LANDSAT data results in a better definition of linears of one or more miles. Long line linears were found in the vicinity of known gas production areas in Ohio.

Baldridge, P. E.↗
NASA NTRS1976

The use of ERTS/LANDSAT imagery in relation to airborne remote sensing for terrain analysis in western Queensland, Australia

The author has identified the following significant results. Distinctive spectral signatures were found associated with areas of near surface bedrock with covered ground east of Dugald River and along the Thorntonia River valley west of Lady Annie. Linears identified in the Dugald River area on LANDSAT 2 imagery taken in March and July 1975 over the Cloncurry-Dobbyn area, displayed preferred orientation. A linear group with NE-SW orientation was identified in the Lady Annie area. In this area, the copper mineralization in the Mt. Kelly area occurs along a well marked linear with NNW/SSE direction apparent on images for March, September, and November 1975. Geobotanical anomalies provided surface expression of the copper deposits in Mt. Kelley.

Cole, M. M.↗
NASA NTRS1976

STS payloads mission control study (continuation phase)

User oriented space transportation system-payload mission control concepts are developed for optimum contribution of ground flight control support to onboard capability to meet STS payload objectives in a cost effective manner. Flight control ground functions are identified for representative payloads. Present and planned NASA facilities for payload control are investigated. Cost effective system concept options are determined for flight control of the payloads. Implementation guidelines are developed for proposed system concept options. Joint preflight activities are identified. Composite joint resources are identified.

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NASA NTRS1976

On vegetation mapping in Alaska using LANDSAT imagery with primary concerns for method and purpose in satellite image-based vegetation and land-use mapping and the visual interpretation of imagery in photographic format

The author has identified the following significant results. A simulated color infrared LANDSAT image covering the western Seward Peninsula was used for identifying and mapping vegetation by direct visual examination. The 1:1,083,400 scale print used was prepared by a color additive process using positive transparencies from MSS bands 4, 5, and 7. Seven color classes were recognized. A vegetation map of 3200 sq km area just west of Fairbanks, Alaska was made. Five colors were recognized on the image and identified to vegetation types roughly equivalent to formations in the UNESCO classification: orange - broadleaf deciduous forest; gray - needleleaf evergreen forest; light violet - subarctic alpine tundra vegetation; violet - broadleaf deciduous shrub thicket; and dull violet - bog vegetation.

Anderson, J. H.↗
NASA NTRS1977

Evaluation of change detection techniques for monitoring coastal zone environments

The author has identified the following significant results. Four change detection techniques were designed and implemented for evaluation: (1) post classification comparison change detection, (2) delta data change detection, (3) spectral/temporal change classification, and (4) layered spectral/temporal change classification. The post classification comparison technique reliably identified areas of change and was used as the standard for qualitatively evaluating the other three techniques. The layered spectral/temporal change classification and the delta data change detection results generally agreed with the post classification comparison technique results; however, many small areas of change were not identified. Major discrepancies existed between the post classification comparison and spectral/temporal change detection results.

Weismiller, R. A.↗
NASA NTRS1977

Application of LANDSAT data to delimitation of avalanche hazards in Montane Colorado

The author has identified the following significant results. Many avalanche hazard zones can be identified on LANDSAT imagery, but not consistently over a large region. Therefore, regional avalanche hazard mapping, using LANDSAT imagery, must draw on additional sources of information. A method was devised that depicts three levels of avalanche hazards according to three corresponding levels of certainty that active avalanches occur. The lowest level, potential avalanche hazards, was defined by delineating slopes steep enough to support avalanches at elevations where snowfall was likely to be sufficient to produce a thick snowpack. The intermediate level of avalanche hazard was interpreted as avalanche hazard zones. These zones have direct and indirect indicators of active avalanche activity and were interpreted from LANDSAT imagery. The highest level of known or active avalanche hazards was compiled from existing maps. Some landslides in Colorado were identified and, to a degree, delimited on LANDSAT imagery, but the conditions of their identification were highly variable. Because of local topographic, geologic, structural, and vegetational variations, there was no unique landslide spectral appearance.

Knepper, D. H., Jr.↗
NASA NTRS1976

The Jovian magnetosphere and magnetopause

The characteristics of the planet Jupiter's inner magnetosphere are examined, taking into account the Pioneer 10 and 11 magnetometer data. Data on the reliability of spherical harmonic expansions are presented in a table. The properties of the Jovian magnetosheath and magnetopause are described. Bow shock and magnetopause crossings were securely identified in plasma data and were usually identified in plasma data and were usually identifiable in the magnetometer data. Explanations for the large number of observed crossings are discussed. It is pointed out that in the case of the outer magnetosphere the observed field strength is nearly an order of magnitude larger than would be expected from Jupiter's dipole moment. The distinguishing characteristics of the magnetic field in the middle magnetosphere are also considered.

Davis, L., Jr.↗
NASA NTRS1977

Pioneer 9 and Pioneer 10 observations of the solar wind associated with the August 1972 events

Observations are presented of the changes in the solar wind proton parameters at 0.8 and 2.2 AU as a result of the solar flares in August 1972. These observations were obtained by the NASA Ames Research Center solar wind plasma analyzer experiments on Pioneer 9 and Pioneer 10. High time resolution measurements are presented of the solar wind proton speed associated with the arrival of the interplanetary shocks at Pioneer 9 and Pioneer 10. For these events, differential ion energy per unit charge spectra are shown which indicate the changes in the solar wind ion distribution function associated with the arrival of each of the interplanetary shocks. Four fast shocks are identified at Pioneer 9, and it is found that previously the time of arrival of the first interplanetary shock at Pioneer 9 was not correctly identified. Two fast shocks and one reverse shock are identified at Pioneer 10.

Intriligator, D. S.↗
NASA NTRS1976

Convection cells in the early lunar magma ocean - Trace-element evidence

A method was proposed for recognizing suites of samples which are related to the differentiation of distinct and regionally separated magmas in the early lunar surface ocean. The sample suites were identified by three Cl-P2O5 compositional groups. New experimental data continue to add samples to these groups. Each magma was associated with a convection cell the boundaries of which are proposed. Independent geochemical evidence supporting a limited number of early magmas is cited. Two new possible Cl-P2O5 groups are identified. Samples not indigenous to a given site and their possible source regions are identified. It is proposed that many Apollo 17 basalts are not locally derived.

Jovanovic, S.↗
NASA NTRS1977

Satellite observations of new infrared sources

Preliminary results are reported for satellite observations of about 1000 IR sources at a wavelength of 2.7 microns. The observations were made in the declination zone between +10 and -10 deg to a limiting flux of 4 by 10 to the -16th power W/sq cm per micron. Of 83 previously unobserved sources, twenty are identified with late-type stars having visual magnitudes of 6 to 9. The nine sources with available luminosity classifications are found to be giant stars, and flux densities at 2.2 and 3.6 microns are predicted for four unreddened stars among these. Three other detected sources are positively identified with red variable stars; twenty more are tentatively identified as such. It is suggested that some of the 40 blank-field 2.7-micron sources detected at high galactic latitude may be Mira variables with thick dust shells located at large distances from the galactic plane.

Heinsheimer, T. F.↗
NASA NTRS1978

Interpolation and Extrapolation of Creep Rupture Data by the Minimum Commitment Method. Part 3: Analysis of Multiheats

The Minimum Commitment Method was applied to two sets of data for which multiple heat information was available. For one alloy, a 304 stainless steel studied in Japan, data on nine well characterized heats were used, while for a proprietary low alloy carbon steel studied in the United Kingdom data were available on seven heats - in many cases to very long rupture times. For this preliminary study no instability factors were used. It was discovered that heat-to-heat variations would be accounted for by introducing heat identifiers in the form A + B log sigma where sigma is the stress and the constants A and B depend only on the heat. With these identifiers all the data could be collapsed onto a single master curve, even though there was considerable scatter among heats. Using these identifiers together with the average behavior of all heats made possible the determination of an accurate constitutive equation for each individual heat. Two basic approaches are discussed for applying the results of the analysis.

Manson, S. S.↗
NASA NTRS1978

Automated tracking of the Florida manatee (Trichechus manatus)

The electronic, physical, biological and environmental factors involved in the automated remote tracking of the Florida manatee (Trichechus manatus) are identified. The current status of the manatee as an endangered species is provided. Brief descriptions of existing tracking and position locating systems are presented to identify the state of the art in these fields. An analysis of energy media is conducted to identify those with the highest probability of success for this application. Logistic questions such as the means of attachment and position of any equipment to be placed on the manatee are also investigated. Power sources and manateeborne electronics encapsulation techniques are studied and the results of a compter generated DF network analysis are summarized.

Michelson, R. C.↗
NASA NTRS1978

Ion drive technology readiness for the 1985 Halley Comet rendezvous mission

This paper summarizes the results of an assessment performed by the Jet Propulsion Laboratory (JPL) in FY 77 of the technology readiness of ion propulsion technology to support a 1985 Halley Comet Rendezvous (HCR) mission. The assessment identifies the status of ion propulsion technology and risk of its utilization to perform the HCR mission as of July 1977 and provides projections of status and risk at the required date for an HCR project start, October 1978. These projections are based on the assumed completion of the development activities ongoing at the time of this assessment and the recommended new activities identified in this paper. The conclusions of the study indicate that a National Aeronautics and Space Administration (NASA) commitment to the performance-demanding HCR mission would involve significant risk, greater than that experienced in any post-1964 planetary mission, despite years of supporting research and advanced development funding for ion propulsion and even assuming the success of an ambitious, aggressive FY 78 pre-project advanced systems technology (AST) program proposed by JPL. Contributing principally to the identified risk are a marginal mass margin of 6.7%, driven by uncertainties in ion drive vehicle masses and an unconfirmed solar array power degradation model of 12%, and technology currently undemonstrated to meet HCR mission requirements in two of the six subsystems of the ion propulsion module: the thrust and solar array subsystems.

John L West↗
NASA NTRS1978

Laser power transmission for space power and propulsion

An early status report is presented for a review being made of the state of development of major components and subsystems required for ground-to-space, space-to-space, or space-to-ground laser power transmission for electric or thermal power or propulsion. System characteristics are being evaluated from an applications viewpoint, and major problem areas are being identified. The object is to identify a rewarding first application of lasers for space power and propulsion. An evolution of laser power transmission capabilities over the next 20 years is projected. Supporting technology requirements are to be identified, priorities set, and continued developments coordinated with other government agencies.

Brantley, L. W.↗
NASA NTRS1978

On the nature of the sources of hard pulse X-ray radiation

Besides the identified sources of cosmic pulse X-ray radiation with globular clusters NGC 6624, NGC 1851 and MXB 1730-335 several new identifications were made. The source in Norma was probably identified with globular cluster NGC 5927, the source in Aquila with globular cluster NGC 6838 (M71), and the source in Puppis with globular cluster NGC 2298. Gamma pulses discovered by the Vela satellites and X-ray pulses thoroughly measured by the SAS-3, Ariel-5, and ANS satellites are thought to be the same phenomenon. The sources of such a radiation must be some kind of peculiarity at the central part of globular clusters; it is most probably a massive black hole. The sources of hard pulse radiation which cannot be identified with globular clusters are considered to be a new kind of galactic object, invisible globular clusters, which are naked nuclei of globular clusters.

Shklovskiy, I. S.↗
NASA NTRS1979

Structural dynamics technology research in NASA: Perspective on future needs

The perspective of a NASA ad hoc study group on future research needs in structural dynamics within the aerospace industry is presented. The common aspects of the design process across the industry are identified and the role of structural dynamics is established through a discussion of various design considerations having their basis in structural dynamics. The specific structural dynamics issues involved are identified and assessed as to their current technological status and trends. Projections of future requirements based on this assessment are made and areas of research to meet them are identified.

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