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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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A two-part valve simplifies the problem of filling large tanks from smaller ones. One part acts as a check valve and remains integral to the recipient system, while the other part is integral to the donor system.
Propagation of oscillations in two-phase system of liquid and its vapor
Guidance system requirements for unmanned Martian propulsive landing capsule
Improved parameters are presented for predicting the tropospheric effect on electromagnetic range measurements from surface meteorological data. Parameters are given for computing the dry component of the zenith radio range effect from surface pressure alone with an rms error of 1 to 2 mm, or the total range effect from the dry and wet components of the surface refractivity, N, and a two-part quartic profile model. The parameters were obtained from meteorological balloon data with improved procedures, including the conversion of the geopotential heights of the balloon data to actual or geometric heights before using the data. The revised values of the parameter k show more latitude variation than is accounted for by the variation of g. This excess variation of k indicates a small latitude variation in the mean molecular weight of air and yields information about the latitude-varying water vapor content of air.
Improved parameters are presented for predicting the tropospheric effect on electromagnetic range measurements from surface meteorological data. More geographic locations have been added to the earlier list. Parameters are given for computing the dry component of the zenith radio range effect from surface pressure alone with an rms error of 1 to 2 mm, or the total range effect from the dry and wet components of the surface refractivity and a two-part quartic profile model. The new parameters are obtained, as before, from meteorological balloon data but with improved procedures, including the conversion of the geopotential heights of the balloon data to actual or geometric heights before using the data. The revised values of the parameter k (dry component of vertical radio range effect per unit pressure at the surface) show more latitude variation than is accounted for by the variation of g, the acceleration of gravity.
Results of a study in which six supine resting subjects, wearing water-perfused suits, had body skin temperature controlled at 35 C for 30 min (control period), then rapidly increased to 40.5 C for 43 to 50 min (heating period) in a two-part experiment. In the first part of the experiment arterial mean pressure (MP) in three men was increased back to, or above control levels at the 30 to 35th min of heating by total occlusion of both legs for 8 to 10 min. Splanchnic blood flow (SBF), which had fallen from 1.4 to 0.9 L/min at occlusion, rose only 0.05 L/min during occlusion. Splanchnic vascular resistance (SVR) rose throughout heating and occlusion. In the second part of the experiment (three men) SBF fell despite a spontaneous rise in MP and aortic pulse pressure prior to leg occlusion. Cardiac output (CO) was measured just before, during and after occlusion. Occlusion raised MP 10 to 15 mm Hg and reduced CO only slightly. It is concluded that falling MP or aortic pulse pressure are not major causes of the splanchnic vasoconstriction in response to heating man.
Evaluation of observations of surface temperature and salinity along the western edge of the Gulf Stream made from a ship and of concurrent temperature observations obtained by instrumented aircraft at six altitudes. The major feature along a five-kilometer line normal to the Stream's edge is a temperature gradient of about 0.75 C/kilometer within which are embedded two abrupt temperature increases of about 1.5 C. Temperature variations were compensated by salinity variations, yielding nearly constant density through the frontal zone; a sharp lateral current shear was associated with the thermohaline mixing region between the steps. The attenuation of surface temperature measured by the airborne radiometer was compared with a theoretical model. The analysis supports the view that a two-part correction technique is required: one part for bulk-skin temperature differences, and another for atmospheric attenuation of sea surface emission due to the mass and temperature of interfering gases.
Recent measurements of thermodynamic properties of oxygen and nitrogen have provided data necessary for development of a single equation of state for both fluids. Data are available in summary report and two-part detailed study on thermodynamic properties of oxygen and nitrogen. Same data are used to develop vapor-pressure equation and heat-capacity equation.
This is a two-part report on solar electric propulsion (SEP) performance sensitivity analysis. The first part describes the preliminary analysis of the SEP thrust system performance for an Encke rendezvous mission. A detailed description of thrust subsystem hardware tolerances on mission performance is included together with nominal spacecraft parameters based on these tolerances. The second part describes the method of analysis and graphical techniques used in generating the data for Part 1. Included is a description of both the trajectory program used and the additional software developed for this analysis. Part 2 also includes a comprehensive description of the use of the graphical techniques employed in this performance analysis.
Description of a two-part clustering technique consisting of (a) a sequential statistical clustering, which is essentially a sequential variance analysis, and (b) a generalized K-means clustering. In this composite clustering technique, the output of (a) is a set of initial clusters which are input to (b) for further improvement by an iterative scheme. This unsupervised composite technique was employed for automatic classification of two sets of remote multispectral earth resource observations. The classification accuracy by the unsupervised technique is found to be comparable to that by traditional supervised maximum-likelihood classification techniques.
Gamma-ray fluxes between 25 keV and 6 MeV were observed by instruments aboard the Environmental Research Satellite-18 (ERS-18)during the great solar flares of May 21 and May 23, 1967. Measurements were made with a 6.35-cm-diameter by 7.65-cm-long Nal scintillation counter with five differential channels between 0.25 and 6.0 MeV. Data obtained during the event at 1945 UT on May 23, 1967, can be fitted by a two-part, power-law, differential-number spectrum. One part is of spectral index 3.2 between 8 keV and 0.6 MeV, and the other is of spectral index 1.2 above 0.6 MeV. An upper limit of 0.52 photons is set for 2.23 MeV line strength for this event. In all three bursts, tentatively associated with white light flares, the MeV-range fluxes declined more slowly than the 25-keV fluxes.
A two-part experiment was carried out on seven men to determine whether skin will respond to increased neurogenic vasoconstrictor activity during heating. The latter was induced by lower body negative pressure of -50 mm Hg applied for 5 of each 15 min in 12 studies with constant, neutral skin temperature (32.2-34.4 C) in a 40-min control period and with skin temperature held at 38 C for 40-70 min. We conclude that during heating, skin retains the ability to vasoconstrict but that this vasoconstriction cannot completely override heat-induced vasodilatation.
Two-part dual-slope system converts both low-level and high-level analog signals at 500 8-bit words/second with an accuracy of 3 percent.
Inexpensive set of modular semirigid box structures serve as multipurpose support for thin panels. Fixture holds several different, interchangeable, two-part, adjustable, contour-board subassemblies. Combining modules allows for accommodation to any length skin or panel.
Two-part coupling system for hose lines combines both connection and filter in one fitting. Flared fittings make coupling less prone to leakage, and reduced number of components speeds operation. These features may make coupler useful with liquid-bulk carriers, where materials (e.g., milk, cooking oil, and liquid sugar) must be transferred quickly from vehicle to storage facility.
Plans for the 1981 Jupiter Orbiter Probe (JOP) mission are presented in some detail. The need for a Jupiter entry probe, remote sensing of the planet, and an orbiter, in addition to flybys, is made clear. Launch hardware, using the Space Shuttle flight system and Interim Upper Stage, is described, along with scientific tasks laid out for the entry probe and the orbiter. Combined analysis of the Jovian magnetosphere and other orbiter missions calls for a two-part orbiter with one part spun and the other de-spun. Related design problems and solutions are described and diagrammed. Jovian moon flybys and orbiter path adjustments by subsequent earth-launched flybys are discussed. The importance of Jupiter data for solar system evolution and possible analysis of early stages of stellar evolution or of a binary system are also treated.
The nucleus of the approach to Spacelab Payload mission management is the establishment of a single point of authority for the entire payload on a given mission. This single point mission manager will serve as a 'broker' between the individual experiments and the STS, negotiating agreements by two-part interaction. The payload mission manager, along with a small support team, will represent the users in negotiating use of STS accommodations. He will provide the support needed by each individual experimenter to meet the scientific, technological, and applications objectives of the mission with minimum cost and maximum efficiency. The investigator will assume complete responsibility for his experiment hardware definition and development and will take an active role in the integration and operation of his experiment.
A description is presented of a simple two-part model which relates the retention of solar-wind-implanted noble gases and N in different grain sizes of lunar soils to the maturation level of that soil. It is assumed that concentrations of solar-wind gases are implanted into surfaces of soil grains in inverse proportion to grain diameter and that differences in irradiation probability and surface saturation as a function of grain diameter generally are not a major factor. The model demonstrates that incorporation of a major fraction of this surface-correlated gas into constructional particles such as agglutinates causes much of the gas to become volume-correlated in mature soils. This volume-correlated gas produces a relative enrichment in gas concentrations in coarser grains and a selective enrichment of more retentive gases (e.g., N) over less retentive gases (e.g., He). It is shown that the maturity model plays a major role in determining the complexities of the distribution of solar-wind gases in soils.