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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 127 records · Page 7

Imaging and Segmenting Grains and Subgrains Using Backscattered Electron Techniques

We present two new methods of processing data from backscattered electron signals in a scanning electron microscope to image grains and subgrains. The first combines data from multiple backscattered electron images acquired at different specimen geometries to (1) better reveal grain boundaries in recrystallized microstructures and (2) distinguish between recrystallized and unrecrystallized regions in partially recrystallized microstructures. The second utilizes spherical harmonic transform indexing of electron backscatter diffraction patterns to produce high angular resolution orientation data that enable the characterization of subgrains. Subgrains are produced during high-temperature plastic deformation and have boundary misorientation angles ranging from a few degrees down to a few hundredths of a degree. Here, we also present an algorithm to automatically segment grains from combined backscattered electron image data or grains and subgrains from high angular resolution electron backscatter diffraction data. Together, these new techniques enable rapid measurements of individual grains and subgrains from large populations.

36 MATERIALS SCIENCE

Apollo guidance, navigation, and control: Candidate configuration trade study, Stellar-Inertial Measurement System (SIMS) for an Earth Observation Satellite (EOS)

The ten candidate SIMS configurations were reduced to three in preparation for the final trade comparison. The report emphasizes subsystem design trades, star availability studies, data processing (smoothing) methods, and the analytical and simulation studies at subsystem and system levels from which candidate accuracy estimates will be presented.

Ogletree, G.

Stability and noise spectra of relative Loran-C frequency comparisons

Relative comparisons of Loran-C frequency transmissions between the master station of Catanzaro (Simeri Crichi) and the X, Z slave stations of Estartit (Spain) and Lampedusa (Italy) are carrying out by the GG LORSTA monitor station of the Mediterranean Sea Loran-C chain. These comparisons are able to emphasize the relative and, under certain conditions, the absolute rate of the emitting standard frequencies of the slave stations and some relevant statistical properties of the Loran-C Method for frequency transmission and time synchronization. The stability of each Loran-C frequency standard transmission is subject to perturbations, more or less known, due to the propagation medium and other causes. Following the Allan (1966) method for data processing, the performance of the relative rate of frequency of the transmissions of the X, Z slave stations are described calculating the standard deviation of a set of N frequency measurements from its mean averaged during sampling times. This standard deviation is designated as the measure of the stability of the Loran-C frequency transmission.

Proverbio, E.

Data for NASA's AVE 3 experiment: 25-mb sounding data and synoptic charts

The atmospheric variability experiment (AVE 3) is described and tabulated rawinsonde data at 25-mb intervals from the surface to 25 mb for the 41 stations is presented. The experiment was conducted between February 6 and February 7, 1975. Brief discussions are given on methods of data processing, changes in the reduction scheme since the AVE 2 pilot experiment, and data accuracy. An example of contact data is presented as well as synoptic charts prepared from the data.

Fuelberg, H. E.

Data for NASA's AVE 4 experiment: 25-mb sounding data and synoptic charts

The AVE 4 Experiment is described and tabulated rawinsonde data at 25-mb intervals from the surface to 25 mb for the 42 stations participating in the experiment are presented. Soundings were taken between 0000 GMT, April 24 and 1200 GMT, April 25, 1975. The methods of data processing and accuracy are discussed. Synoptic charts prepared from the data are presented, as well as an example of contact data.

Fucik, N. F.

Data for NASA's AVSSE 2 experiment: 25-mb sounding data and synoptic charts

This report describes the AVSSE II Experiment and presents tabulated rawinsonde data at 25 mb intervals from the surface to 25 mb for the 23 stations participating in the experiment. Soundings were taken between 1200 GMT, May 6 and 1200 GMT, May 7, 1975. Brief discussions are given on the methods of data processing and accuracy. Synoptic charts prepared from the data are presented, as well as an example of contact data.

Fucik, N. F.

Data for NASA's AVSSE 1 experiment: 25-mb sounding data and synoptic charts

The AVSSE I Experiment and is described tabulated rawinsonde data is presented for 25-mb intervals from the surface to 25mb for the 24 stations participating in the experiment. Soundings were taken between 1200 GMT, April 27, and 1200 GMT, April 28, 1975. Brief discussions are given on the methods of data processing and accuracy. Synoptic charts prepared from the data are presented, as well as an example of contact data.

Fucik, N. F.

Pressure Contact Sounding Data for NASA's Atmospheric Variability Experiment (AVE 3)

The basic rawinsonde data are described at each pressure contact from the surface to sounding termination for the 41 stations participating in the AVE III measurement program that began at 0000 GMT on February 6 and ended at 1200 GMT on February 7, 1975. Soundings were taken at 3-hour intervals during a large period of the experiment from most stations within the United States east of about 105 degrees west longitude. Methods of data processing, change in reduction scheme since the AVE II pilot experiment, and data accuracy are briefly discussed. An example of contact data is presented, and microfiche cards of all the contact data are included in the appendix. The AVE III project was conducted to better understand and establish the extent of applications for meteorological satellite sensor data through correlative ground truth experiments and to provide basic experimental data for use in studies of atmospheric scales of-motion interrelationships.

Fuelberg, H. E.

Data for NASA's AVE 4 experiment: 25 mb sounding data and synoptic charts

The AVE IV Experiment is described and tabulated rawinsonde data at 25 mb intervals from the surface to 25 mb for the 42 stations participating in the experiment are presented. Soundings were taken between 0000 GMT, April 24, and 1,200 GMT, April 25, 1975. The methods of data processing and accuracy are briefly discussed. Synoptic charts prepared from the data are presented, as well as an example of contact data.

Fucik, N. F.

Data for NASA's AVSSE 2 experiment: 25 mb sounding data and synoptic charts

The AVSSE II experiment is described and tabulated rawinsonde data at 25 mb intervals from the surface to 25 mb for the 23 stations participating in the experiment are presented. Soundings were taken between 1,200 GMT, May 6, and 1,200 GMT, May 7, 1975. The methods of data processing and accuracy are briefly discussed. Synoptic charts prepared from the data are presented, as well as an example of contact data.

Fucik, N. F.

Data for NASA's AVSSE 1 Experiment: 25 Mb Sounding Data and Synoptic Charts

The AVSSE 1 Experiment is described and tabulated rawinsonde data at 25 mb intervals from the surface to 25 mb are presented for the 24 stations participating in the experiment. Soundings were taken between 1,200 GMT, April 27, and 1,200 GMT, April 28, 1975. The methods of data processing and accuracy are briefly discussed. Synoptic charts prepared from the data are presented, as well as an example of contact data.

Fucik, N. F.

Data for NASA's AVE 5 experiment: 25 mb sounding data and synoptic charts

The AVE V Experiment is described and tabulated rawinsonde data at 25-mb intervals from the surface to 25 mb for the 23 stations participating in the experiment are presented. Soundings were taken between 0000 GMT, June 11, and 1200 GMT, June 12, 1976. The methods of data processing and accuracy are briefly discussed. An example of contact data is also included.

Humbert, M. E.

Data for NASA's AVE 6 experiment: 25-mb sounding data and synoptic charts

The Atmospheric Variability Experiments 6 experiment is described, and tabulated rawinsonde data at 25-mb intervals from the surface to 25 mb for the 22 stations participating in the experiment is presented. Soundings were taken between 0000 GMT 27 May and 1200 GMT 28 May 1977. The methods of data processing and their accuracy are briefly discussed. Synoptic charts prepared from the data are presented together with an example of contact data.

Dupuis, L. R.

NASA's AVE 7 experiment: 25-mb sounding data

The AVE 7 Experiment is described and tabulated rawinsonde data at 25 mb internals from the surface to 25 mb for the 24 stations participating in the experiment are presented. Soundings were taken between 0000GMT May 2 and 1200 GMT May 3, 1978. The methods of data processing and the accuracy are briefly discussed. Selected synoptic charts prepared from the data are presented as well as an example of contact data. A tabulation of adverse weather events that occured during the AVE 7 period, including freezing temperature, snow, tornadoes, damaging winds, and flooding, is presented.

Davis, J. G.

Synoptic analyses, 5-, 2-, 1-, and 0.4-millibar surfaces for July 1976 through June 1977

Meteorological rocketsonde and satellite radiance data are employed for analyses of a continuing series of high-altitude constant-pressure charts. The automated methods of data processing and the objective analysis procedures are described. Broad-scale analyses of temperature and geopotential height for the Northern Hemisphere 5-, 2-, 1-, and 0.4-mb surfaces are presented for each week of the period July 1976 through June 1977. Brief discussions of the variations of the temperature and height fields throughout the period are also given.

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