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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
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Resource and environmental surveys from space with the thematic mapper in the 1980's

The selection of observation of vegetation is the primary optimization objective of the thematic mapper. The following are aspects of plans for the thematic mapper: (1) to include an appropriately modified first generation MSS in the thematic mapper mission; (2) to provide assured coverage for a minimum of six years to give agencies and other users an opportunity to justify the necessary commitment of resources for the transition into a completely valid operational phase; (3) to provide for global, direct data read-out, without the necessity for on-board data storage or dependence on foreign receiving stations; (4) to recognize the operational character of the thematic mapper after successful completion of its experimental evaluation; and (5) to combine future experimental packages with compatible orbits as part of the operational LANDSAT follow-on payloads.

Source record↗
NASA NTRS1977

Low speed aerodynamic characteristics of a vectored thrust V/STOL transport with two lift/cruise fans

A wind tunnel test was conducted to obtain power on low speed characteristics of a twin fan vectored thrust V/STOL transport aircraft. Longitudinal, as well as some lateral directional data, were analyzed. Hover, STOL, and conventional flight modes were investigated. Determination of STOL characteristics, hover characteristics, roll control effectiveness and aircraft attitude were evaluated. The study also included various means to improve the lifting capability of the aircraft such as by application of fuselage strakes, exhaust vanes capable of shifting the thrust vector aft, and external flap blowing for STOL performance.

Renselaer, D. J.↗
NASA NTRS1976

Morphology of Arabidopsis grown under chronic centrifugation and on the clinostat

Morphological measurements were made on populations of Arabidopsis thaliana grown from seed for 21 days under essentially constant environmental conditions except for the influence of gravitational or centrifugal accelerations. Growth conditions were what had been proposed for experiments in an artificial satellite. Observations are reported for plants grown at normal 1-g upright or on horizontal clinostats and for plants grown on a centrifuge. Increased g-force, up to 15 times normal, was found to have significant but small effects on some morphological end points. The plants' sensitivity to the magnitude of the g-force was much less than to its vector direction. Data from centrifuge experiments were extrapolated to zero-g to predict a set of morphological characteristics of a plant developing in the satellite environment. As an alternative means of predicting properties of a zero-g plant, characteristics of plants grown on horizontal clinostats were measured. The results of these two predictive methods were not in agreement. Clinostat grown plants were morphologically distinct from upright stationary controls.

Brown, A. H.↗
NASA NTRS1976

Close-up view of 20 March 1976 tornadoes - Sinking cloud tops to suction vortices

The article describes an airborne mission using a Learjet to secure direct data on a family of tornadoes spawned by a rotating thunderstorm in the Missouri-Illinois-Indiana area in March 1976 following an unusually warm February. Weakening of the tornado following increased cloud-scale vertical motion, predicted by a model constructed by Fujita (1972), was confirmed. The aircraft inspected overshooting cloud tops, examined subsidence (holes and depressions) in anvil tops it overflew, and surveyed footprints left by the tornadoes and tornado-blown litter on the ground traversed by the disturbances. Subsidence of cloud tops in advance of violent tornadoes below was confirmed. Isolated and multiple suction vortices left their characteristic ground marks; three scales of motion: tornado cyclone, tornado, and suction vortex, are evidenced by the ground truth.

Fujita, T. T.↗
NASA NTRS1977

Significance of operator variation and the angle of illumination in lineament analysis on synoptic images

The significance of operator variation and the angle of illumination in acquired imagery is analyzed for lineament analysis. Five operators analyzed a LANDSAT image and four photographs of a plastic relief map illuminated at a low angle from varying directions of the Prescott, Arizona region. Significant differences were found in both number and length of the lineaments recognized by the different investigators for the images. The actual coincidence of lineaments recognized by the investigators for the same image is exceptionally low. Even the directional data on lineament orientation is significantly different from operator to operator and from image to image. Cluster analysis of the orientation data displays a clustering by operators rather than by images. It is recommended that extreme caution be taken before attempting to compare different investigators' results in lineament analysis.

Siegal, B. S.↗
NASA NTRS1978

A hard X-ray and gamma ray observation of the 22 November 1977 solar flare

The Franco-Soviet experiment package Signe 2 MP for solar and cosmic X and gamma ray observations, launched aboard a Soviet Prognoz satellite into a highly eccentric earth orbit is described. An uncollimated NaI detector 37 mm thick by 90 mm diameter, placed on the upper surface of the satellite faced the sun. A collimated lateral NaI detector 14 mm thick by 38 mm diameter also faced the sun, and a similar lateral detector faced the anti-solar direction. Data tapes reveal an intense solar flare up to energies of up to 5 MeV, with evidence for line emission at 2.23 MeV and possibly 4.4 MeV. The event observed was associated with the Mc Math Plage Region 15031, and an H-alpha flare of importance 2B. It is not yet clear what radio emission is associated with the X-ray observation.

Chambon, G.↗
NASA NTRS1979

VHF downline communication system for SLAR data

A real time VHF downlink communication system is described for transmitting side-looking airborne radar (SLAR) data directly from an aircraft to a portable ground/shipboard receiving station. Use of this receiving station aboard the U.S. Coast Guard icebreaker Mackinaw for generating real-time photographic quality radar images is discussed. The system was developed and demonstrated in conjunction with the U.S Coast Guard and NOAA National Weather Service as part of the Project Icewarn all weather ice information system for the Great Lakes Winter Navigation Program.

Schertler, R. J.↗
NASA NTRS1979

VHF downlink communication system for SLAR data

This paper describes a real-time VHF downlink communication system for transmitting side-looking airborne-radar (SLAR) data directly from an aircraft to a portable ground/shipboard receiving station. Use of this receiving station aboard the U.S. Coast Guard icebreaker Mackinaw for generating real-time photographic quality radar images will be discussed. The system was developed and demonstrated in conjunction with the U.S. Coast Guard and NOAA National Weather Service as part of the Project Icewarn all-weather ice information system for the Great Lakes Winter Navigation Program.

Schertler, R. J.↗
NASA NTRS1982

Parallel-Access Alinement Network Using Barrel Switches

Practical version of parallel-access alinement network utilizes two barrel switches for interfacing N parallel memory modules with N parallel processing elements. Switches are interconnected where 17 memory ports (MP's) are connected to 17 processor ports (PP's). Network uses two electronic barrel switches to direct data flow in parallel data-processing system. Each switch can shift a multibit parallel input a predetermined number of places to left or right, end off, or end around in one clock-pulse.

Barnes, George H.↗
NASA NTRS1981

Summary of measurement results of ozone, methane, and nonmethane hydrocarbons for C-54 aircraft. 1979 Southeastern Virginia Urban Plume Study

Methane, nonmethane hydrocarbon, and ozone data collected in a C-54 aircraft during the 1979 Southeastern Virginia Urban Plume Study are presented. Three major aircraft experiments were flown on five separate days in August collecting 20 hours of flight data. Direct correlation between ozone and hydrocarbon plumes was observed on several occasions.

Cofer, W. R., III↗
NASA NTRS1982

Gamma-ray burst observations by the HEAO-3 high-resolution gamma-ray spectrometer

Special attention is given to two bursts occurring on November 16, 1979. Because of the close temporal coincidence of the two events, the possibility that both originated from a single celestial source is considered, as is the possibility that the scanning motion of HEAO-3 (nominal spin period, 20 min) was such as to exclude the first from the (approximately 30 deg FWHM) field of view of the germanium detectors and include the second. Directional data from the relative response of the shield pieces and earth occultation constraint are found to be consistent with this interpretation, and high-resolution spectral data from the second burst are discussed in this light. It is noted that recent unpublished analyses of long-baseline timing data from interplanetary spacecraft reveal that the response in the HEAO high-resolution detectors is probably earth albedo scattering. This, it is noted, can be an important systematic effect in low-earth orbit.

Wheaton, W. A.↗
NASA NTRS1985

Mars atmospheric circulation - Aspects from Viking Landers

Winds measured by the two Viking Landers have been filtered and then compared with predictions from the general circulation model and to Orbiter observations of clouds and surface phenomena that indicate wind direction. This was done to determine the degree to which filtered winds may represent aspects of the general circulation. Excellent agreement was found between wind direction data from Lander 1 and the model predictions and Orbiter observations. For Lander 2, agreement was generally good, but there were periods of disagreement which indicate that the filtering did not remove other extraneous effects. It is concluded that Lander 1 gives a good representation of the general circulation at 22.5 deg N latitude but that Lander 2 is suspect. Most wind data from Lander 1 have yet to be analyzed. It appears that when analyzed these Lander 1 data (covering 3.5 Mars years) can provide information about interannual variations in the general circulation at the Lander latitude.

Ryan, J. A.↗
NASA NTRS1986

Three-Frequency Water-Vapor Radiometer

Measurements increase accuracies of delay predictions. Threefrequency microwave radiometer measures quantity of water vapor in atmosphere, part of effort to determine microwave-signal delays due to water vapor. Delay estimates necessary for accurate determination of distances in geodesy and related applications as very-long-baseline interferometry. Water-vapor data directly useful in weather research.

Janssen, M. A.↗
NASA NTRS1986

Satellite accelerometer measurements of neutral density and winds during geomagnetic storms

A new thermospheric wind measurement technique is reported which is based on a Satellite Electrostatic Triaxial Accelerometer (SETA) system capable of accurately measuring accelerations in the satellite's in-track, cross-track and radial directions. Data obtained during two time periods are presented. The first data set describes cross-track winds measured between 170 and 210 km during a 5-day period (25 to 29 March 1979) of mostly high geomagnetic activity. In the second data set, cross-track winds and neutral densities from SETA and exospheric temperatures from the Millstone Hill incoherent scatter radar are examined during an isolated magnetic substorm occurring on 21 March 1979. A polar thermospheric wind circulation consisting of a two cell horizontal convection pattern is reflected in both sets of cross-track acceleration measurements. The density response is highly asymmetric with respect to its day/night behavior. Latitude structures of the density response at successive times following the substorm peak suggest the equatorward propagation of a disturbance with a phase speed between 300 and 600 m/s. A deep depression in the density at high latitudes (less than 70 deg) is evident in conjunction with this phenomenon. The more efficient propagation of the disturbance to lower latitudes during the night is probably due to the midnight surge effect.

Marcos, F. A.↗
NASA NTRS1985

A knowledge based software engineering environment testbed

The Carnegie Group Incorporated and Boeing Computer Services Company are developing a testbed which will provide a framework for integrating conventional software engineering tools with Artifical Intelligence (AI) tools to promote automation and productivity. The emphasis is on the transfer of AI technology to the software development process. Experiments relate to AI issues such as scaling up, inference, and knowledge representation. In its first year, the project has created a model of software development by representing software activities; developed a module representation formalism to specify the behavior and structure of software objects; integrated the model with the formalism to identify shared representation and inheritance mechanisms; demonstrated object programming by writing procedures and applying them to software objects; used data-directed and goal-directed reasoning to, respectively, infer the cause of bugs and evaluate the appropriateness of a configuration; and demonstrated knowledge-based graphics. Future plans include introduction of knowledge-based systems for rapid prototyping or rescheduling; natural language interfaces; blackboard architecture; and distributed processing

Gill, C.↗
NASA NTRS1985

Evolution of basin and range structure in the Ruby Mountains and vicinity, Nevada

Results from various age dating techniques, seismic reflection profiling hydrocarbon maturation studies, and structural analysis were used to evaluate the Cenozoic deformation in the Ruby Mountains and adjoining ranges (pinyon Range and Cortez Range) in Elko and Eureka Counties, Nevada. Age dating techniques used include potassium-argon ages of biotites from granites published by Kistler et al. (1981) and fission track ages from apatite and zircon. Fission track ages from apatite reflect a closing temperature of 100 plus or minus 20 deg C. Zircon fission track ages reflect a closing temperature of 175 plus or minus 25 deg C and potassium-argon ages from brotite reflect a closing temperature of 250 plus or minus 30 deg C. Thus these results allow a reasonably precise tracking of the evolution of the ranges during the Cenozoic. Seismic reflection data are available from Huntington Valley. Access to seismic reflection data directly to the west of the Harrison Pass Pluton in the central Ruby Mountains was obtained. In addition results are available from several deep exploration holes in Huntington Valley.

Blackwell, D. D.↗
NASA NTRS1986

Mature data transport and command management services for the Space Station

The duplex space/ground/space data services for the Space Station are described. The need to separate the uplink data service functions from the command functions is discussed. Command management is a process shared by an operation control center and a command management system and consists of four functions: (1) uplink data communications, (2) management of the on-board computer, (3) flight resource allocation and management, and (4) real command management. The new data service capabilities provided by microprocessors, ground and flight nodes, and closed loop and open loop capabilities are studied. The need for and functions of a flight resource allocation management service are examined. The system is designed so only users can access the system; the problems encountered with open loop uplink access are analyzed. The procedures for delivery of operational, verification, computer, and surveillance and monitoring data directly to users are reviewed.

Carper, R. D.↗