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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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Development of an advanced spacecraft water and waste materials processing system

An Integrated Waste Management-Water System (WM-WS) which uses radioisotopes for thermal energy is described and results of its trial in a 4-man, 180 day simulated space mission are presented. It collects urine, feces, trash, and wash water in zero gravity, processes the wastes to a common evaporator, distills and catalytically purifies the water, and separates and incinerates the solid residues using little oxygen and no chemical additives or expendable filters. Technical details on all subsystems are given along with performance specifications. Data on recovered water and heat loss obtained in test trials are presented. The closed loop incinerator and other projects underway to increase system efficiency and capacity are discussed.

Murray, R. W.↗
NASA NTRS1980

A study of radio frequency interference with the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR)

One of the important objectives of the NIMBUS-7 Scanning Multichannel Microwave Radiometer (SMMR) is to demonstrate the feasibility of all weather measurements of various ocean parameters; such as sea surface temperature (SST) and near surface wind speed (WS). These ocean parameters can be determined from multispectral measurements of ocean brightness temperatures in the microwave region of the electromagnetic spectrum. These microwave measurements, however, are distorted if the field of view of the SMMR antenna encounters radio transmissions from terrestrial sources. Sources of terrestrial Radio Frequency Interference (RFI) in the SMMR ocean data were identified. Its extent and characteristics over different ocean areas on the Earth were determined.

Kogut, J. A.↗
NASA NTRS1981

Study project of intrusive rocks: States of Espirito Santo and Rio de Janeiro, south and east of Minas Gerais and southeast of the state of Sao Paulo

The feasibility of mapping intrusive rocks in polycyclic and polymetamorphic areas using the logic method for photointerpretation of LANDSAT and radar imagery was investigated. The resolution, scale and spectral characteristics of the imagery were considered. Spectral characteristics of the intrusive rock units mapped using image 100 were investigated. It was determined that identification of acidic and basic intrusive bodies and determination of their relationships with principal structural directions using the logic method was feasible. Tectonic compartments were subdivided into units according to their predominant lithographic types, ignoring stratigraphy. The principal directions of various foliations, faults, megafolds, and fractural systems were defined. Delineation of the boundaries of intrusive bodies mapped using the spectral characteristics of Image 100 imagery ws determined to be more accurate than visual analysis. A 1:500,000 scale map of intrusions in the areas studied was generated.

Dejesusparada, N.↗
NASA NTRS1981

Methods of editing cloud and atmospheric layer affected pixels from satellite data

Plotted transects made from south Texas daytime HCMM data show the effect of subvisible cirrus (SCI) clouds in the emissive (IR) band but the effect is unnoticable in the reflective (VIS) band. The depression of satellite indicated temperatures ws greatest in the center of SCi streamers and tapered off at the edges. Pixels of uncontaminated land and water features in the HCMM test area shared identical VIS and IR digital count combinations with other pixels representing similar features. A minimum of 0.015 percent repeats of identical VIS-IR combinations are characteristic of land and water features in a scene of 30 percent cloud cover. This increases to 0.021 percent of more when the scene is clear. Pixels having shared VIS-IR combinations less than these amounts are considered to be cloud contaminated in the cluster screening method. About twenty percent of SCi was machine indistinguishable from land features in two dimensional spectral space (VIS vs IR).

Nixon, P. R.↗
NASA NTRS1982

Investigation of spray characteristics for flashing injection of fuels containing dissolved air and superheated fuels

The flow, atomization and spreading of flashing injector flowing liquids containing dissolved gases (jet/air) as well as superheated liquids (Freon II) were considered. The use of a two stage expansion process separated by an expansion chamber, ws found to be beneficial for flashing injection particularly for dissolved gas systems. Both locally homogeneous and separated flow models provided good predictions of injector flow properties. Conventional correlations for drop sizes from pressure atomized and airblast injectors were successfully modified, using the separated flow model to prescribe injector exit conditions, to correlate drop size measurements. Additional experimental results are provided for spray angle and combustion properties of sprays from flashing injectors.

Solomon, A. S. P.↗
NASA NTRS1981

Stimulation of body weight increase and epiphyseal cartilage growth by insulin like growth factor

The ability of insulin-like growth factor (IGF) to induce growth in hypophysectomized immature rats was tested by continuous infusion of the partially purified factor at daily doses of 6, 21, and 46 mU for an 8-day period. A dose-dependent growth of the proximal epiphyseal cartilage of the tibia and an associated stimulation of the primary spongiosa were produced by these amounts of IGF. The two highest doses of IGF also resulted in dose-dependent increases of body weight. Gel permeation of the sera at neutrality showed that the large-molecular-weight IGF binding protein was not induced by the infusion of IGF, whereas it ws generated in the sera of hypophysectomized rats that were infused with daily doses of 86 mU of human growth hormone.

Ellis, S.↗
NASA NTRS1981

Oxygen generation subsystem for spacecraft

Recovery of oxygen from water will be needed on future long-duration manned space missions. An oxygen generation subsystem (OGS) for NASA based on the alkaline electrolyte, static feed water electrolysis concept. Recent advances in hardware development have resulted in the design, fabrication and testing of a self-contained, one-person capacity OGS (WS-1). This subsystem consists of three major parts: a six-cell electrochemical module to generate the product O2, a coolant control assembly to maintain module temperature and a pressure controller which maintains product gas pressures. The subsystem provides 0. 82 kg/d O2 while operating at a current density of 206 mA/ sq cm, a temperature of 339 K and a pressure of 1240 kPa.

Schubert, F. H.↗
NASA NTRS1984

Thermal response of Space Shuttle wing during reentry heating

A structural performance and resizing (SPAR) finite element thermal analysis computer program was used in the heat transfer analysis of the space shuttle orbiter that was subjected to reentry aerodynamic heatings. One wing segment of the right wing (WS 240) and the whole left wing were selected for the thermal analysis. Results showed that the predicted thermal protection system (TPS) temperatures were in good agreement with the space transportation system, trajectory 5 (STS-5) flight-measured temperatures. In addition, calculated aluminum structural temperatures were in fairly good agreement with the flight data up to the point of touchdown. Results also showed that the internal free convection had a considerable effect on the change of structural temperatures after touchdown.

Gong, L.↗
NASA NTRS1981

Development of low cost custom hybrid microcircuit technology

Selected potentially low cost, alternate packaging and interconnection techniques were developed and implemented in the manufacture of specific NASA/MSFC hardware, and the actual cost savings achieved by their use. The hardware chosen as the test bed for this evaluation ws the hybrids and modules manufactured by Rockwell International fo the MSFC Flight Accelerometer Safety Cut-Off System (FASCOS). Three potentially low cost packaging and interconnection alternates were selected for evaluation. This study was performed in three phases: hardware fabrication and testing, cost comparison, and reliability evaluation.

Perkins, K. L.↗
NASA NTRS1983

Orbiter operations in close proximity to free-flying satellites or formation flying in space

The seventh orbital flight of the Space Shuttle had as one of its primary objectives the testing of the vehicle's capability for proximity operations (defined as anytime the Orbiter is within 1000 feet of another satellite). The goals of these tests were to obtain flight data on different techniques for separation from, stationkeeping with, and approach and capture of a free-flying satellite. This included the acquisition of data on technique evaluation as to propellant usage, time required, crew workload, plume disturbance to the payload by the reaction control system, and jet plume impingement. The tests were also to provide data on the rendezvous radar and optical sighting devices performance in this environment. It is concluded that the Orbiter proved to be a very responsive vehicle that ws straightforward to fly in the vicinity of another satellite given the proper experience base with ground simulations.

Crippen, R. L.↗
NASA NTRS1984

Thermal response of Space Shuttle wing during reentry heating

A structural performance and resizing (SPAR) finite element thermal analysis computer program was used in the heat transfer analysis of the Space Shuttle Orbiter that was subjected to reentry aerodynamic heatings. One wing segment of the right wing (WS 240) and the whole left wing were selected for the thermal analysis. Results showed that the predicted thermal protection system (TPS) temperatures were in good agreement with the space transportation system, trajectory 5 (STS-5) flight-measured temperatures. In addition, calculated aluminum structural temperatures were in fairly good agreement with flight data up to the point of touchdown. Results also showed that the internal free convection has a considerable effect on the change of structural temperatures after touchdown.

Gong, L.↗
NASA NTRS1986

Terrace width variations in complex lunar craters

The widths of terrace structures in complex craters on the moon are compared to existing theoretical models of their origin. Terrace widths in an individual crater increase monotonically outward toward the crater rim. Similarly, the width W of the terraces lying closest to the rim of a crater of diameter D increases monotonically, obeying a least-squares power-law relation WS (km) = 0.09D exp 0.87 km). A simple model of slumping that ignores inertial forces and assumes a constant bedrock yield strength is in good agreement with the observations.

Pearce, Steven J.↗
NASA NTRS1987

The moderately interacting Algol-type eclipsing binary RY Geminorum

Ultraviolet spectra of the Algol-type semidetached system RY Geminorum, whose components can be described as A0 V and K0 IV, have been matched to the ultraviolet spectrum by Kurucz (1979) model atmospheres, and a best fit is found for T(eff) = 9150 K. Comparison with standard star spectra requires that this value be raised to 9400 K. The color excess of the system is determined to be no more than E(B-V) = 0.03 mag; the distance to the system is about 360 pc. The masses are approximately 2.36 and 0.38 solar masses, and the radii are 2.5 and 5.8 solar radii, respectively. The separation of the two centers is 26 solar radii. Evidence for a circumstellar line absorption is found in optical and ultraviolet spectrograms, and evidence is found in IUE spectra taken in partial eclipse for circumstellar emission lines of the type detected previously in the WS Serpentis stars and in several semidetected systems of the Algol type.

Plavec, Mirek J.↗
NASA NTRS1990

Amazon Basin ozone and aerosol - Wet season observations

The ozone and aerosol number density data obtained from aircraft flights over the Amazon Basin (AB) during April and May of 1987 are summarized with particular attention given to the general characteristics of ozone and aerosol for wet season (WS), compared to dry season (DS), meteorology. It is concluded that the AB provides favorable conditions for the production of hydroxyl radical and subsequent chemical and photochemical reactions which generate or consume key atmospheric trace species. It is determined that a negative ozone gradient exists within the mixed layer (ML). WSML ozone is about 7 ppbv lower than that of DS. The net sink characteristics of the WSML are seen throughout the troposphere of the AB in that the ozone at 3-4 km altitude is typically 15-25 ppbv as compared to DS values of 30-35 ppbv. In terms of aerosol source characteristics of the AB, ML aerosols are 5-10 times higher than observed in the troposphere with ML values of 100-200 aerosols/cu cm. An analysis of aerosol size distribution data is presented.

Gregory, Gerald L.↗
NASA NTRS1990

Ginga observations of a long-duration X-ray flare in the Algol system

Algol was observed by the Ginga X-ray satellite for about 2 days in January 1989, including both the primary and most of the secondary optical eclipses. No evidence for X-ray eclipses was seen. A large flare lasting over 12 h was detected prior to and during secondary eclipse. The flare began with a peak temperature of about 69 MK, gradually decaying to about 36 MK. Variable Fe line emission at 6.7 keV ws observed. The Fe line equivalent width is in clear disagreement with theoretical predictions for an optically thin plasma.

Stern, R. A.↗
NASA NTRS1994

The ratios of carbon and non-radiogenic helium and argon isotopes in the mantle and crustal rocks

The studies of the relations of carbon and primary isotopes of noble gases were carried out on the natural gases and on the mantle rocks from the mantle M-type sources, which represent the degassed mantle reservoir (MORB's). These works has the aim of estimation of the values of the C/3He ratios in the deep mantle fluids to determine the flux of the mantle CO2 on the basis of known flux of primary mantle 3He. It was found, that in the natural gases the values of the C/3He ratios fall into the range from 1 times E plus 6 to 1 times E plus 15, and in the fluids of MORB's are constant near 2 times E plus 9. We have studied the mantle rocks from the relatively undergassed mantle P minus type sources: continental; Baikal Rift (Siberia), Mongolia, Catalonia (Spain), Pannonia Depression (central Europe) and ocean; Spietzbergen isl., Hawaii isl., Canarian isl. It ws found, that in mantle xenolites and the host alkaline basalts from the continental rifts and ocean islands, the values of the C/3He ratios fall into the range from E plus 11 to E plus 15 (and this result needed to be explained; the higher carbon to helium ratios is relatively undergassed mantle reservoir compared with the degassed one, requires whether hilly compatibility of helium compared with carbon, whether additional flux of 3He to the degassed mantle reservoir). From the other hand it was found that in the mantle rocks from the sources of P minus and M minus types, continental carbonatites, the values of the C/36Ar ratios are constant in the range from E plus 9 to E plus 10, the close values have the MORB's also.

Lokhov, K.↗
NASA NTRS1997

Advanced Signal Processing Methods Applied to Digital Mammography

The work reported here is on the extension of the earlier proposal of the same title, August 1994-June 1996. The report for that work is also being submitted. The work reported there forms the foundation for this work from January 1997 to September 1997. After the earlier work was completed there were a few items that needed to be completed prior to submission of a new and more comprehensive proposal for further research. Those tasks have been completed and two new proposals have been submitted, one to NASA, and one to Health & Human Services WS). The main purpose of this extension was to refine some of the techniques that lead to automatic large scale evaluation of full mammograms. Progress on each of the proposed tasks follows. Task 1: A multiresolution segmentation of background from breast has been developed and tested. The method is based on the different noise characteristics of the two different fields. The breast field has more power in the lower octaves and the off-breast field behaves similar to a wideband process, where more power is in the high frequency octaves. After the two fields are separated by lowpass filtering, a region labeling routine is used to find the largest contiguous region, the breast. Task 2: A wavelet expansion that can decompose the image without zero padding has been developed. The method preserves all properties of the power-of-two wavelet transform and does not add appreciably to computation time or storage. This work is essential for analysis of the full mammogram, as opposed to selecting sections from the full mammogram. Task 3: A clustering method has been developed based on a simple counting mechanism. No ROC analysis has been performed (and was not proposed), so we cannot finally evaluate this work without further support. Task 4: Further testing of the filter reveals that different wavelet bases do yield slightly different qualitative results. We cannot provide quantitative conclusions about this for all possible bases without further support. Task 5: Better modeling does indeed make an improvement in the detection output. After the proposal ended, we came up with some new theoretical explanations that helps in understanding when the D4 filter should be better. This work is currently in the review process. Task 6: N/A. This no longer applies in view of Tasks 4-5. Task 7: Comprehensive plans for further work have been completed. These plans are the subject of two proposals, one to NASA and one to HHS. These proposals represent plans for a complete evaluation of the methods for identifying normal mammograms, augmented with significant further theoretical work.

Stauduhar, Richard P.↗