1,536 research outputs found
The isotropic correlation function of plane figures: the triangle case
The knowledge of the isotropic correlation function of a plane figure is
useful to determine the correlation function of the cylinders having the plane
figure as right-section and a given height as well as to analyze the out of
plane intensity collected in grazing incidence small-angle scattering from a
film formed by a particulate collection of these cylinders. The correlation
function of plane polygons can always be determined in closed algebraic form.
Here we report its analytic expression for the case of a triangle. The
expressions take four different forms that depend on the relative order among
the sides and the heights of the triangle.Comment: 11 pages, 2 figure
Revised reference model for nitric acid
A nearly global set of data on the nitric acid distribution was obtained for seven months by the Limb Infrared Monitor of the Stratosphere (LIMS) experiment on the Nimbus 7 spacecraft. The evaluation of the accuracy, precision, and resolution of these data is described, and a description of the major features of the nitric acid distributions is presented. The zonal mean for nitric acid is distributed in a stratospheric layer that peaks near 30 mb, with the largest mixing ratios occurring in polar regions, especially in winter
On-orbit cryogenic fluid transfer
A number of future NASA and DOD missions have been identified that will require, or could benefit from resupply of cryogenic liquids in orbit. The most promising approach for accomplishing cryogenic fluid transfer in the weightlessness environment of space is to use the thermodynamic filling technique. This approach involves initially reducing the receiver tank temperature by using several charge hold vent cycles followed by filling the tank without venting. Martin Marietta Denver Aerospace, under contract to the NASA Lewis Research Center, is currently developing analytical models to describe the on orbit cryogenic fluid transfer process. A detailed design of a shuttle attached experimental facility, which will provide the data necessary to verify the analytical models, is also being performed
Acoustic-gravity Waves in the Earth's Atmosphere. I - the General Nature of Acoustic-gravity Waves. II - Acoustic- Gravity Wave Ducting in the Atmosphere by Vertical Temperature Structure
Nature, propagation, and ducting of acoustic gravity waves in earths atmospher
Structural perfection of Hg1−xCdxTe Grown by THM
The defect structure of single crystals of Hg1-xCdxTe grown by the travelling heater method (THM) has been investigated using X-ray double crystal topography and a chemical etching technique. The structural perfection is found to depend on the ratio of growth and solidus temperature Tg/Ts
The synthesis of 15 mu infrared horizon radiance profiles from meteorological data inputs
Computational computer program for modeling infrared horizon radiance profile using pressure and temperature profile input
Intercomparisons of HIRDLS, COSMIC and SABER for the detection of stratospheric gravity waves
Colocated temperature profiles from the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC), High Resolution Dynamics Limb Sounder (HIRDLS) and the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) mission are compared over the years 2006–2007 to assess their relative performances for the detection of stratospheric gravity waves. Two methods are used, one based on a simple comparison of the standard deviations and correlation coefficients of high-pass filtered profiles from each instrument, and the other based on Stockwell transform analyses of the profiles for vertical wavelength and temperature perturbation scales. It is concluded, when allowing for their different vertical resolution capabilites, that the three instruments reproduce each other's results for magnitude and vertical scale of perturbations to within their resolution limits in approximately 50 % of cases, but with a positive frequency and temperature bias in the case of COSMIC. This is possibly indicative of a slightly higher vertical resolution being available to the constellation than estimated
Limb radiance inversion radiometer
Engineering and scientific objectives of the LRIR experiment are described along with system requirements, subassemblies, and experiment operation. The mechanical, electrical, and thermal interfaces between the LRIR experiment and the Nimbus F spacecraft are defined. The protoflight model qualification and acceptance test program is summarized. Test data is presented in tables to give an overall view of each test parameter and possible trends of the performance of the LRIR experiment. Conclusions and recommendations are included
Spacecraft instrument calibration and stability
The following topics are covered: instrument degradation; the Solar Backscatter Ultraviolet (SBUV) Experiment; the Total Ozone Mapping Spectrometer (TOMS); the Stratospheric Aerosol and Gas Experiment 1 (SAGE-1) and SAGE-2 instruments; the Solar Mesosphere Explorer (SME) UV ozone and near infrared airglow instruments; and the Limb Infrared Monitor of the Stratosphere (LIMS)
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