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Analysis of Shane telescope aberration before and after collimation (open access)

Analysis of Shane telescope aberration before and after collimation

The Shane 3 meter telescope was recollimated in August 1998 to remove aberrations that were perceived to affect image quality in good seeing conditions. The Lick Adaptive Optics system is capable, indirectly, of measuring the static aberrations introduced by the telescope primary and secondary mirror pair. Since A0 runs were scheduled both before and after the collimation, this allowed a comparison of the pre and post collimation telescope aberrations. The absolute calibration of the wavefront measurement is complicated by the indirect measurement technique, which uses the shape of the deformable mirror in its closed-loop corrected position as an indicator of telescope wavefront. The shape of the deformable mirror is not measured directly, but is inferred from the voltages applied to its piezoelectric actuators. The actuators are known to have temperature-dependent hysteresis and is thus a source of error in this technique. In November, an interferometer was added to the A0 system which will allow more direct measurements of corrected wavefront in future tests. Data from six measurements in July (pre-collimation) and nine measurements in September and November (post-collimation) were analyzed. The resulting phase maps show a slight difference in the wavefront with some improvement in the coma and spherical zernike …
Date: January 26, 1999
Creator: Gavel, D T
System: The UNT Digital Library
Assessment of Radionuclides in the Savannah River Site Environment Summary (open access)

Assessment of Radionuclides in the Savannah River Site Environment Summary

This document summarizes the impact of radionuclide releases from Savannah River Site (SRS) facilities from 1954 through 1996. The radionuclides reported here are those whose release resulted in the highest dose to people living near SRS.
Date: January 26, 1999
Creator: Carlton, W.H.
System: The UNT Digital Library
Data Summary Report for the 1998 Semiannual Tritium Surveys for Fourmile Branch and the F- and H-Area Seeplines (open access)

Data Summary Report for the 1998 Semiannual Tritium Surveys for Fourmile Branch and the F- and H-Area Seeplines

This report presents a summary of the definitive data validation and verification for the 1998 semiannual tritium surveys for Fourmile Branch and the F- and H-Area Seeplines. The project was performed under the direction of WSRC EAS/Ecology. This report was prepared under the direction of EPD/EMS.
Date: January 26, 1999
Creator: Koch, J.
System: The UNT Digital Library
An indirect sensing technique for diesel fuel quantity control. Technical progress report, October 1--December 31, 1998 (open access)

An indirect sensing technique for diesel fuel quantity control. Technical progress report, October 1--December 31, 1998

Work has proceeded intensely with the objective of completing the commercial prototype system prior to the end of the contract period. At the time of this report, testing and refinement of the commercial version of the system has not been completed. During this reporting period, several major milestones were reached and many significant lessons were learned. These are described. The experimental retrofit system has achieved all performance objectives in engine dynamometer tests. The prototype commercial version of the system will begin demonstration service on the first of several Santa Maria Area Transit (SMAT) transit buses on February 1, 1999. The commercial system has been redesignated the Electronic Diesel Smoke Reduction System (EDSRS) replacing the original internal pseudonym ADSC. The focus has been narrowed to a retrofit product suitable for installation on existing mechanically-governed diesel engines. Included in this potential market are almost all diesel-powered passenger cars and light trucks manufactured prior to the introduction of the most recent clean diesel engines equipped with particulate traps and electronic controls. Also included are heavy-duty trucks, transit vehicles, school buses, and agricultural equipment. This system is intended to prevent existing diesel engines from overfueling to the point of visible particulate emissions (smoke), while …
Date: January 26, 1999
Creator: MacCarley, C. Arthur
System: The UNT Digital Library
Joint Combined Exchange Training (JCET) and Human Rights: Background and Issues for Congress (open access)

Joint Combined Exchange Training (JCET) and Human Rights: Background and Issues for Congress

The National Defense Authorization Act for Fiscal Years 1992 and 1993 allows U.S. special operations forces (SOF) to train under the Joint Combined Exchange Training (JCET) program in foreign countries, and does not prohibit training in nations where human rights violations have been reported. Such training includes instructing host government military units in lethal and nonlethal skills. Controversy has erupted over JCET missions in countries whose militaries are suspected or known to have committed human rights abuses. This report describes relevant legislation, SOF, JCET, alleged human rights abuses, and recent congressional initiatives and discusses further options and issues.
Date: January 26, 1999
Creator: Story, William C., Jr.
System: The UNT Digital Library
Numerical Weather Forecasting at the Savannah River Site (open access)

Numerical Weather Forecasting at the Savannah River Site

Facilities such as the Savannah River Site (SRS), which contain the potential for hazardous atmospheric releases, rely on the predictive capabilities of dispersion models to assess possible emergency response actions. The operational design in relation to domain size and forecast time is presented, along with verification of model results over extended time periods with archived surface observations.
Date: January 26, 1999
Creator: Buckley, Robert L.
System: The UNT Digital Library
Solid Phase Microextraction and Miniature Time-of-Flight Mass Spectrometer (open access)

Solid Phase Microextraction and Miniature Time-of-Flight Mass Spectrometer

A miniature mass spectrometer, based on the time-of-flight principle, has been developed for the detection of chemical warfare agent precursor molecules. The instrument, with minor modifications, could fulfill many of the needs for sensing organic molecules in various Defense Programs, including Enhanced Surveillance. The basic footprint of the instrument is about that of a lunch box. The instrument has a mass range to about 300, has parts-per-trillion detection limits, and can return spectra in less than a second. The instrument can also detect permanent gases and is especially sensitive to hydrogen. In volume, the device could be manufactured for under $5000.
Date: January 26, 1999
Creator: Hiller, j.m.
System: The UNT Digital Library