Transient phenomena in heat transfer across surfaces in contact.
Space-time temperature distribution in one- dimensional systems with heat transfer across contacts
TRANSIENT HEATING↗
SEARCH · Engineering Papers
Results for “time distribution”
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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Gaseous electronics
Electron-electron relaxation rates determined from time-dependent electron velocity distribution
VELOCITY DISTRIBUTION↗
Some analytical and experimental phase-locked loop results for low signal-to-noise ratios.
Phase locked results for low SNRs pertaining to phase errors probability, cumulative and variance distribution, including time intervals between cycle-slipping
Charles, F. J.↗
Directional discontinuities in the interplanetary magnetic field.
Discontinuities in interplanetary magnetic field direction presented on mesoscale from Pioneer 6 observation, emphasizing distribution in time
Burlaga, L. F.↗
Fluctuations in monatomic gases.
Fluctuation spectra of monatomic gases, using two time probability distributions for distribution function autocorrelations
Montgomery, D.↗
Single or joint amplitude distribution analyzer Patent
Cathode ray oscilloscope for analyzing electrical waveforms representing amplitude distribution of time function
Tetsuka, G. M.↗
Buildup of laser oscillations from quantum noise
Laser oscillation buildup from quantum noise, deriving equations of motion for moments of photon distribution and time dependence
Lamb, W. E., Jr.↗
A 100-micrometer (100-micron)map of the galactic center
The results of a survey made of the galactic center by a balloon-borne telescope are reported. The telescope mapped far infrared emission over a 5 degree portion of the sky with overlapping scans perpendicular to the plane. Data show emission is a continuous band along the galactic plane and emission perpendicular to the plane is on the order of 2 degrees. The map covers, for the first time, the distribution of dust in the galactic plane.
Hoffman, W.↗
Very High-Frequency (VHF) ionospheric scintillation fading measurements at Lima, Peru
During the spring equinox of 1970, scintillating signals at VHF (136.4 MHz) were observed at Lima, Peru. The transmission originated from ATS 3 and was observed through a pair of antennas spaced 1200 feet apart on an east-west baseline. The empirical data were digitized, reduced, and analyzed. The results include amplitude probability density and distribution functions, time autocorrelation functions, cross correlation functions for the spaced antennas, and appropriate spectral density functions. Results show estimates of the statistics of the ground diffraction pattern to gain insight into gross ionospheric irregularity size, and irregularity velocity in the antenna planes.
Blank, H. A.↗
Mariner 9 ultraviolet spectrometer experiment - Mars atomic oxygen 1304-A emission.
Selected results are presented for an analysis of Mariner 9 1304-A data from the first 100 passes. Based on a comparison of limb data, the exospheric temperature appears lower on several Mariner 9 passes than when Mariner 6 and 7 encountered the planet in 1969. Temperatures of 300 and 350 K are considered in the atmospheric modeling. At 300 K, derived values of the atomic oxygen concentration are typically between 0.5 and 1% of the total density at 135 km, based on fitting theoretical intensities to limb data from several passes. Structure in the limb data below 200 km suggests the possibility that approximately 0.2 kR of the observed approximately 0.8 kR near 150 km is due to dissociative excitation of CO2. There is variability in limb profiles, thus indicating changes in the O distribution with time. The variability does not appear to follow a recognizable pattern. Interpretation of the 1304-A disk data shows a correlation in intensity with the 10.7-cm solar flux and larger O concentrations in the afternoon than in the morning. The correlation in intensity with the 10.7-cm flux is probably due largely to variation in the solar 1304-A fluxes.
Strickland, D. J.↗
The longitudinal movement of stratospheric ozone waves as determined by satellite
The Nimbus III Infrared Interferometer Spectrometer sensor provides several thousand total ozone data points over the entire globe each day. A time-longitudinal distribution of total ozone for 60 deg S is shown. A selection of this latitude makes it possible to compare the data with radiance values computed by Fritz (1970). Hemispheric differences in longitudinal progression during June 1969 are discussed together with group- and phase-velocities of ozone 'waves.'
Reiter, E. R.↗
McLaughlin and Mars
McLaughlin formulated a novel explanation for the Martian albedo markings and their variations. This explanation, the volcanic-aeolian hypothesis, is one of the very few prespacecraft views of planet-wide phenomena on Mars which have stood the test of time. The distribution of albedo markings is considered along with secular changes on Mars and seasonal changes in region Syrtis Major. Mariner 9 has demonstrated that aeolian transport is the dominant factor in determining the distribution of albedo markings on Mars.
Veverka, J.↗
Atmospheric aerosols: A literature summary of their physical characteristics and chemical composition
This report contains a summary of 199 recent references on the characterization of atmospheric aerosols with respect to their composition, sources, size distribution, and time changes, and with particular reference to the chemical elements measured by modern techniques, especially activation analysis.
Harris, F. S., Jr.↗
Tropical F region winds from O I 1356-A and forbidden OI 6300-A emissions. I - Theory
The paper theoretically investigates the relationship of neutral winds and E x B plasma drifts to the time-dependent distribution of 1356-A and 6300-A airglow intensities in the region of the Appleton anomaly. Radiative recombination, ion-ion neutralization, and dissociative recombination are considered as main mechanisms in producing the atomic oxygen tropical nightglow. A quantitative relation is determined between the neutral wind velocities and the resultant asymmetry in the emissions about the dip equator. The height difference at northern and southern conjugate points is shown to be linearly related to the vector sum of the wind velocity components along the magnetic meridian at the latitude of the conjugate points. The height difference at conjugate points may be used to study the pattern of neutral wind velocities in the tropical ionosphere.
Bittencourt, J. A.↗
The morphological evolution of mare-highland contacts - A potential measure of relative mare surface age
The uniform breaks in slopes along many mare-highland contacts may be debris aprons transported primarily by impact erosion at relatively slow rates. Other suggestions, such as the 'high lava mark' hypothesis, appear inadequate to explain all of the unique characteristics of these widespread features. There is a reasonable correlation of overall slope form (profile) and apron distribution with established mare age provinces. Distinctive debris aprons in the younger maria could represent the initial stages of lunar slope degradation produced mainly by the postmare impact flux. The growth of debris aprons must be qualitatively related to the impact flux recorded on adjacent mare surfaces and could provide an approximate means of extrapolating relative mare ages to highland scarps and crater walls. By combining detailed measurements of lunar slopes with development of a realistic model for impact modification of these features, approximate limits for the cumulative lunar flux distribution through time might be derived.
Young, R. A.↗
Monte Carlo simulation of wave sensing with a short pulse radar
A Monte Carlo simulation is used to study the ocean wave sensing potential of a radar which scatters short pulses at small off-nadir angles. In the simulation, realizations of a random surface are created commensurate with an assigned probability density and power spectrum. Then the signal scattered back to the radar is computed for each realization using a physical optics analysis which takes wavefront curvature and finite radar-to-surface distance into account. In the case of a Pierson-Moskowitz spectrum and a normally distributed surface, reasonable assumptions for a fully developed sea, it has been found that the cumulative distribution of time intervals between peaks in the scattered power provides a measure of surface roughness. This observation is supported by experiments.
Levine, D. M.↗
Creation of lumped parameter thermal model by the use of finite elements
In the finite difference technique, the thermal network is represented by an analogous electrical network. The development of this network model, which is used to describe a physical system, often requires tedious and mental data preparation and checkout by the analyst which can be greatly reduced through the use of the computer programs to develop automatically the mathematical model and associated input data and graphically display the analytical model to facilitate model verification. Three separate programs are involved which are linked through common mass storage files and data card formats. These programs are SPAR, CINGEN and GEOMPLT, and are used to (1) develop thermal models for the MITAS II thermal analyzer program; (2) produce geometry plots of the thermal network; and (3) produce temperature distribution and time history plots.
Source record↗
Model for interpreting Doppler broadened optical line emission measurements on axially symmetric plasma
A plasma model, previously developed to interpret neutral-particle analyzer measurements on E x B heating devices, is adapted to analyze Doppler broadened charge-exchange-neutral lines measured by an optical monochromator. Comparison of theoretical with experimental results indicates that azimuthal drift as well as cyclotron motion are quite influential in determining line shapes and widths, and thus important in temperature determination, even when the monochromator line of sight is intersecting the plasma axis of symmetry. At this central sighting position, however, results are quite insensitive to radial ion density distribution when time lag between the charge-exchange-excitation events and emission is neglected. Line shapes and widths obtained by sighting across chords of plasma at various distances from the plasma axis of symmetry indicate a strong dependence on time lag.
Englert, G. W.↗