SEARCH · Search NASA

Results for “Virginia”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 577 records · Page 32

All sources NASA NTRS DOE OSTI

NASA NTRS1975

Preliminary data for the 20 May 1974, simultaneous evaluation of remote sensors experiment

Several remote sensors were simultaneously used to collect data over the tidal James River from Hopewell to Norfolk, Virginia. Sensors evaluated included the Multichannel-Ocean Color Sensor, multispectral scanners, and multispectral photography. Ground truth measurements and remotely sensed data are given. Preliminary analysis indicates that suspended sediment and concentrated industrial effluent are observable from all sensors.

Johnson, R. W.↗

NASA NTRS1975

Development of superconductor magnetic suspension and balance prototype facility for studying the feasibility of applying this technique to large scale aerodynamic testing

The unique design and operational characteristics of a prototype magnetic suspension and balance facility which utilizes superconductor technology are described and discussed from the point of view of scalability to large sizes. The successful experimental demonstration of the feasibility of this new magnetic suspension concept of the University of Virginia, together with the success of the cryogenic wind-tunnel concept developed at Langley Research Center, appear to have finally opened the way to clean-tunnel, high-Re aerodynamic testing. Results of calculations corresponding to a two-step design extrapolation from the observed performance of the prototype magnetic suspension system to a system compatible with the projected cryogenic transonic research tunnel are presented to give an order-of-magnitude estimate of expected performance characteristics. Research areas where progress should lead to improved design and performance of large facilities are discussed.

Zapata, R. N.↗

NASA NTRS1975

Oil-pollution detection and monitoring from space using ERTS-1

The author has identified the following significant results. Three reported spills were investigated using four digital computer, compatible techniques on ERTS - 1 data. A spill on the Atlantic Ocean (off Virginia) was studied to develop spectral signatures. Another spill, in Oakland Bay, was studied by ratioing spectral channels (to try to eliminate turbidity effects) and by summing different spectral channels to look for anomolus values caused by oil. The final spill, off Southern California, was investigated by looking for anomolus values in each channel separately. Results indicate that any of these methods might be usable if the spill is large enough to be seen by satellite, if the spill occurs more than a few kilometers off shore, and if the sky and water are relatively clear. In the case of the Atlantic spill, identification of material was not possible; and in the other two cases, the spills could not be detected at all. ERTS-1 was not considered feasible for this type of work because of its 18 day overpass frequency, the few spectral channels, the extended bandwidths, and the long, information retrieval time.

Horvath, R.↗

NASA NTRS1975

Investigation of current university research concerning energy conversion and conservation in small single-family dwellings

An investigation was made of university research concerning energy conversion and conservation techniques which may be applied in small single-family residences. Information was accumulated through published papers, progress reports, telephone conversations, and personal interviews. A synopsis of each pertinent investigation is given. Finally, a discussion of the synopses is presented and recommendations are made concerning the applicability of concepts for the design and construction of NASA-Langley Research Center's proposed Technology Utilization House in Hampton, Virginia.

Grossman, G. R.↗

NASA NTRS1975

Development of an airborne laser bathymeter

An airborne laser depth sounding system was built and taken through a complete series of field tests. Two green laser sources were tried: a pulsed neon laser at 540 nm and a frequency-doubled Nd:YAG transmitter at 532 nm. To obtain a depth resolution of better than 20 cm, the pulses had a duration of 5 to 7 nanoseconds and could be fired up to at rates of 50 pulses per second. In the receiver, the signal was detected by a photomultiplier tube connected to a 28 cm diameter Cassegrainian telescope that was aimed vertically downward. Oscilloscopic traces of the signal reflected from the sea surface and the ocean floor could either be recorded by a movie camera on 35 mm film or digitized into 500 discrete channels of information and stored on magnetic tape, from which depth information could be extracted. An aerial color movie camera recorded the geographic footprint while a boat crew of oceanographers measured depth and other relevant water parameters. About two hundred hours of flight time on the NASA C-54 airplane in the area of Chincoteague, Virginia, the Chesapeake Bay, and in Key West, Florida, have yielded information on the actual operating conditions of such a system and helped to optimize the design. One can predict the maximum depth attainable in a mission by measuring the effective attenuation coefficient in flight. This quantity is four times smaller than the usual narrow beam attenuation coefficient. Several square miles of a varied underwater landscape were also mapped.

Kim, H., H.↗

NASA NTRS1975

Tidewater metropolitan area transportation survey study

Results of a survey conducted in southeastern Virginia to identify public opinion regarding requirements for future public transportation are analyzed. The effects of age and income level on attitudes concerning city living and no importance of various characteristics described for urban transportation systems are identified.

Ficht, J. C.↗

NASA NTRS1974

Coastal wetlands - Prospects for satellite inventory

It is pointed out that coastal wetlands are among the nation's most valuable natural resources. A relatively low cost and moderately accurate method for mapping these areas would, therefore, be very attractive. It appears that such a method could be found by utilizing ERTS-1 data. Two test sites were selected for an intensive study of the feasibility of such an approach. One test area involves a salt marsh complex located at the mouth of the Chincoteague Bay in Virginia. The second area constitutes a near-saline marsh at the mouth of the Nanticoke River, Maryland. The study shows that ERTS-1 digital data provide maximum gray-level resolution for the mapping of wetland species and features.

Anderson, R. R.↗

NASA NTRS1974

C-band station coordinate determination for the Geos-C altimeter calibration area

Dynamical orbital techniques were employed to estimate the center-of-mass station coordinates of six C-band radars located in the designated primary Geos-C radar altimeter calibration area. This work was performed in support of the planned Geos-C mission (December 1974 launch). The sites included Bermuda, Grand Turk, Antigua, Wallops Island (Virginia), and Merritt Island (Florida). Two sites were estimated independently at Wallops Island yielding better than 40 cm relative height recovery, with better than 10 cm and 1m (relative) recovery for phi and lambda, respectively. The tracking data used in this analysis were taken during 1969 when the radars tracked the Geos-II transponder. In all, over 120 passes of data were used. Range biases were estimated. Error analysis and comparisons with other investigators indicate that better than 2m (1 sigma) relative recovery has been achieved at all sites.

Klosko, S. M.↗

NASA NTRS1974

Coastal wetlands analysis from ERTS MSS digital data and field spectral measurements

Classification, delineation and evaluation of coastal wetlands can be made on the basis of major vegetative associations. To produce wetland maps, two vegetation-analysis look-up tables were developed for use in the ERTS ANALYSIS System. These look-up tables are based on Earth Resources Technology Satellite (ERTS) digital values in Multispectral Scanner (MSS) bands 4, 5, and 7 and were developed using seasonal spectral reflectance measurements from field observations. Computer-generated maps at an approximate scale of 1:20,000 were produced for the primary test site, Chincoteague Marsh, Virginia. There is a high degree of accuracy in the identification of wetland features and plant associations. The classification was also tested on other Atlantic coast salt marshes and a brackish marsh in the Chesapeake Bay.

Carter, V.↗

NASA NTRS1975

Analysis of nighttime E-region winds and ionization production

In the analysis existing measurements of nighttime E-region electron densities are separated in two groups. The first group includes a series of five rocket measurements which were taken during the night of February 22, 1968. The second group consists of a collection of rocket measurements taken near midnight at Wallops Island, Virginia, under varying conditions of geomagnetic activity. Information is obtained about the ionization production as well as the dynamics in the nighttime E region.

Geller, M. A.↗

NASA NTRS1975

A comparison of dustsonde and LIDAR measurements of stratospheric aerosols

This paper describes the results and analysis of an experiment to compare the stratospheric aerosol profiles as measured by a balloon-borne in situ particle counter and by the backscattered light from a ground-based laser radar (LIDAR) operating at a wavelength of 6943 A. The profile comparison agrees within the experimental errors for particles with radii greater than 0.25 micrometer and for altitudes between 15 and 28 kilometers. Following the calibration tests, the LIDAR was used to monitor the stratospheric aerosols at Hampton, Virginia. Enhanced backscatter appeared sporadically in November and December of 1974 over Hampton; scattering ratios averaged over altitude increments of 450 meters range from 1.10 at 20 kilometers in early November to 3.3 at 17 kilometers on December 18. The source of this enhanced backscattering is attributed to the aerosols associated with the eruption of the Fuego volcano in Guatemala in mid-October.

Remsberg, E. E.↗

NASA NTRS1975

Planning air transport network in Appalachia

Main issues to be considered in designing an air transport system are discussed, and a model for the selection of an optimal air network for a region is presented. It was desired to have the ability to consider a dense network of nodes and air routes and variations in schedules on routes, which in combination would represent virtually all conceivable alternatives. Linear and integer programming were chosen as the most promising analysis methodologies. Integer programming was found to be intractable, while linear programming provided efficient solutions. The model was applied to studying the feasibility of a STOL network in West Virginia. Based on allowable paths, an examination of intercity demands, and established growth points, desired levels of service expressed as minimum flights were determined for certain city pairs.

Carter, E. C.↗

NASA NTRS1977

Solar heated and cooled office building

Installation at NASA Langley Research Center, Hampton, Virginia, serves as full-scale working test-bed facility to test flat-plate solar-energy collector systems.

Maag, W. L.↗

NASA NTRS1975

Radar derived spatial statistics of summer rain. Volume 1: Experiment description

An experiment was performed at Wallops Island, Virginia, to obtain a statistical description of summer rainstorms. Its purpose was to obtain information needed for design of earth and space communications systems in which precipitation in the earth's atmosphere scatters or attenuates the radio signal. Rainstorms were monitored with the high resolution SPANDAR radar and the 3-dimensional structures of the storms were recorded on digital tape. The equipment, the experiment, and tabulated data obtained during the experiment are described.

Katz, I.↗

NASA NTRS1975

Monitoring water quality from LANDSAT

Water quality monitoring possibilities from LANDSAT were demonstrated both for direct readings of reflectances from the water and indirect monitoring of changes in use of land surrounding Swift Creek Reservoir in a joint project with the Virginia State Water Control Board and NASA. Film products were shown to have insufficient resolution and all work was done by digitally processing computer compatible tapes. Land cover maps of the 18,000 hectare Swift Creek Reservoir watershed, prepared for two dates in 1974, are shown. A significant decrease in the pine cover was observed in a 740 hectare construction site within the watershed. A measure of the accuracy of classification was obtained by comparing the LANDSAT results with visual classification at five sites on a U-2 photograph. Such changes in land cover can alert personnel to watch for potential changes in water quality.

Barker, J. L.↗

NASA NTRS1975

General aviation and community development

The summer program is summarized. The reports presented concern (1) general aviation components, (2) general aviation environment, (3) community perspective, and (4) transportation and general aviation in Virginia.

Sincoff, M. Z.↗

NASA NTRS1975

A method for the determination of potentially profitable service patterns for commuter air carriers

A methodology for estimating market conception was developed as a part of the short-haul air transportation program. It is based upon an analysis of actual documents which provide a record of known travel history. Applying this methodology a forecast was made of the demand for an air feeder service between Charlottesville, Virginia and Dulles International Airport. Local business travel vouchers and local travel agent records were selected to provide the documentation. The market was determined to be profitable for an 8-passenger Cessna 402B aircraft flying a 2-hour daily service pattern designed to mesh to the best extent possible with the connecting schedules at Dulles. The Charlottesville - Dulles air feeder service market conception forecast and its methodology are documented.

Ransone, R. K.↗

NASA NTRS1975

Community level impacts of expanding underground coal mining

The potential secondary consequences of rapid community growth in deep mining localities and the ability of affected communities to absorb and manage such growth are discussed. Areas discussed include Sweetwater County, Wyoming, and Marion and Monongalia Counties, West Virginia.

Coates, V. T.↗