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Technique for dynamic range reduction for Landsat ratio images

Description: The LANDSAT ratio image, obtained by dividing one MSS band by another on a point-by-point basis, has become an established tool for geological applications over the past several years. Display of such images can be difficult since the dynamic range can extend from zero to infinity. A scheme for dynamic range reduction, based on a mathematical model of the multispectral image, is presented. It can be implemented on stand-alone digital image processing systems as well as general purpose computers… more
Date: January 1, 1978
Creator: Wecksung, G.W. & Breedlove, J.R. Jr.
Partner: UNT Libraries Government Documents Department
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Kilowatt Isotope Power System: component report for the Ground Demonstration System Accumulator

Description: The Model Number ORC1A3A01 System Accumulator for the Kilowatt Isotope Power System was expulsion tested and demonstrated to be in compliance with the requirements of Sundstrand Explusion Test Procedure, TP 400. Test requirements of TP 400 were extracted from the Kilowatt Isotope Power System, Ground Demonstration System Test Plan.
Date: January 31, 1978
Creator: Brainard, E.L.
Partner: UNT Libraries Government Documents Department
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Radioactivities of Long Duration Exposure Facility (LDEF) materials: Baggage and bonanzas

Description: Radioactivities in materials onboard the returned Long Duration Exposure Facility (LDEF) satellite have been studied by a variety of techniques. Among the most powerful is low-background Ge-semiconductor detector gamma-ray spectrometry, illustrated here by results obtained at the Lawrence Berkeley Laboratory's (LBL) Low Bakground Facilities, in a multi-laboratory collaboration coordinated by Dr. Thomas Parnell's team at the Marshall Spacecraft Center, Huntsville, Alabama.
Date: August 1, 1991
Creator: Smith, A. R. & Hurley, D. L.
Partner: UNT Libraries Government Documents Department
open access

Kilowatt Isotope Power System: component test report for the Ground Demonstration System Alternator Stator

Description: Results are presented of acceptance tests conducted on the Alternator Stator, S/N 002, for the Kilowatt Isotope Power System. These results show that the Alternator Stator, S/N 002 for the Kilowatt Isotope Power System has satisfactorily completed the testing set forth within Sundstrand Test Specification 2538. Test requirements of TS 2538 were extracted from the Kilowatt Isotope Power System, and Phase I Test Plan.
Date: April 25, 1978
Creator: Brainard, E.L.
Partner: UNT Libraries Government Documents Department
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Kilowatt isotope power system. Phase II plan. Volume V. Safety, quality assurance and reliability

Description: The development of a Kilowatt Isotope Power System (KIPS) was begun in 1975 for the purpose of satisfying the power requirements of satellites in the 1980's. The KIPS is a /sup 238/PuO/sub 2/-fueled organic Rankine cycle turbine power system to provide a design output of 500 to 2000 W. Included in this volume are: launch and flight safety considerations; quality assurance techniques and procedures to be followed through system fabrication, assembly and inspection; and the reliability program ma… more
Date: March 15, 1978
Partner: UNT Libraries Government Documents Department
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Simulation experiments and solar wind sputtering

Description: In order to isolate the role played by solar wind sputtering from other lunar surface phenomena a number of simulation experiments were performed, including isotope abundance measurements of Ca sputtered from terrestrial fluorite and plagioclase by 50-keV and 130-keV /sup 14/N beams, measurement of the energy distribution of U atoms sputtered with 80-keV /sup 40/Ar, and measurement of the fraction of sputtered U atoms which stick on the surfaces used to collect these atoms. 10 references. (JFP)
Date: January 1, 1978
Creator: Griffith, J. E.; Papanastassiou, D. A.; Russell, W. A.; Tombrello, T. A. & Weller, R. A.
Partner: UNT Libraries Government Documents Department
open access

Computational determination of ballistic limits for a simple Whipple bumper shield

Description: A series of numerical simulations has been performed using the multi-dimensional hydrodynamics code CTH to computationally determine a ballistic limit for a Whipple bumper shield. The ballistic limit is generally characterized as a critical diameter such that particle diameters greater than the ballistic limit will generate debris clouds that will penetrate the rear wall and particle diameters less than the ballistic limit will not. The particular shield design used for these analyses is define… more
Date: January 1, 1991
Creator: Hertel, E.S.; Chhabildas, L.C.; Yarrington, L. (Sandia National Labs., Albuquerque, NM (United States)) & Hill, S.A. (National Aeronautics and Space Administration, Huntsville, AL (United States). George C. Marshall Space Flight Center)
Partner: UNT Libraries Government Documents Department
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Disruption of satellite-to-ground station communication links by nuclear fireballs

Description: Diffraction around nuclear fireballs near the line of sight for satellite-to-ground communication links is calculated numerically. The geometry allows assumption of geometric optics and plane-wave signals. The fireball is modeled as an opaque disk normal to the line of sight. The effect of disk shape and edge taper is considered. 13 figures, 1 table.
Date: October 1, 1977
Creator: Sullivan, T.D.
Partner: UNT Libraries Government Documents Department
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Analysis of organizational options for the uranium enrichment enterprise in relation to asset divesture. [BPA; TVA; SYNFUELS; CONRAIL; British TELECOM; COMSTAT]

Description: This report presents a comparison of the characteristics of some prominent examples of independent government corporations and agencies with respect to the Department of Energy's (DOE) uranium enrichment enterprise. The six examples studied were: the Bonneville Power Administration (BPA); the Tennessee Valley Authority (TVA); the Synthetic Fuels Corporation (SYNFUELS); the Consolidated Rail Corporation (CONRAIL); the British Telecommunications Corporation (British TELECOM); and the Communicatio… more
Date: August 1, 1986
Creator: Harrer, B. J.; Hattrup, M. P.; Dase, J. E. & Nicholls, A. K.
Partner: UNT Libraries Government Documents Department
open access

Nuclear technologies for Moon and Mars exploration

Description: Nuclear technologies are essential to successful Moon and Mars exploration and settlements. Applications can take the form of nuclear propulsion for transport of crews and cargo to Mars and the Moon; surface power for habitats and base power; power for human spacecraft to Mars; shielding and life science understanding for protection against natural solar and cosmic radiations; radioisotopes for sterilization, medicine, testing, and power; and resources for the benefits of Earth. 5 refs., 9 figs… more
Date: January 1, 1991
Creator: Buden, D.
Partner: UNT Libraries Government Documents Department
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Quality assurance program plan applicable to the KIPS technology verification phase

Description: This Quality Program Plan describes the manner in which the Energy Systems Unit of the Advanced Technology Group Division of Sunstrand Corporation applies its Quality Assurance Program and Systems to control and assure commpliance to the Quality requirements in accordance with NRA-1, dated July 1, 1977, in support of the Kilowatt Isotope Power Systems (KIPS) Program Technology Verification Phase.
Date: October 4, 1978
Partner: UNT Libraries Government Documents Department
open access

Calibration of an electron/proton monitor for the earth's radiation belt at 4 R/sub E/

Description: A charged particle dosimeter (the Burst Detector Dosimeter or BDD) was designed and fabricated and will be flown on certain of the Global Positioning Satellite (GPS) series of spacecraft. The BDD will monitor the dose received by the GPS spacecraft from the fluxes of electrons and protons in the Earth's radiation belt. The BDD uses absorbers in front of silicon sensors to determine the energy thresholds for measuring incident particle fluxes; and the magnitude of energy loss in a single sensor … more
Date: March 1, 1982
Creator: Higbie, P.R.; Belian, R.D.; Argo, H.V. & Baker, D.N.
Partner: UNT Libraries Government Documents Department
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Off-nadir optical remote sensing from satellites for vegetation identification

Description: Today's satellite remote sensing systems rely heavily on spectral signatures for scene identification from nadir observations. We propose to use angular signatures as complementary scene identifiers when off-nadir sensing is possible. Specifically, the hot spot (Heiligenschein) of plant canopies is recognized as an atmosphere-invariant angular reflectance signature that carries information about the plant stand architecture which may be useful for instant crop identification from off-nadir sate… more
Date: May 30, 1986
Creator: Gerstl, S.A.W.
Partner: UNT Libraries Government Documents Department
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Global positioning system measurements over a strain monitoring network in the eastern two-thirds of the United States

Description: A 45-station geodetic network was established in 1987 using global positioning system (GPS) technology to provide a means of monitoring strain and deformation in the central and eastern United States. Reduction of the initial epoch data showed that accuracies of 1 to 3 cm can be achieved for horizontal position, provided sufficient observations are available and there are four or more fiducial stations whose positions are known a priori, for example from Very Long Baseline Interferometry measur… more
Date: September 1, 1991
Creator: Strange, W.E.
Partner: UNT Libraries Government Documents Department
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THE SNAP II POWER CONVERSION SYSTEM TOPICAL REPORT NO. 9, ALTERNATOR ANALYSIS, DESIGN AND DEVELOPMENT

Description: The 3 kw nuclear auxiliary power unit deslgnated SNAP II is intended for use in a satellite vehicle. The system consists of a reactor heat source, a mercury Rankine engine, and a permanent magnet alternator. The design details, test results, and development of the SNAP lI alternator are presented. (auth)
Date: October 31, 1962
Creator: Bucklin, R.L.; Galysh, J.W. & Morgan, H.J.
Partner: UNT Libraries Government Documents Department
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Kilowatt isotope power system. Phase II plan. Volume I. Phase II program plan

Description: The development of a Kilowatt Isotope Power System (KIPS) was begun in 1975 for the purpose of satisfying the power requirements of satellites in the 1980's. The KIPS is a /sup 238/PuO/sub 2/-fueled organic Rankine cycle turbine power system to provide a design output of 500 to 2000 W. Phase II of the overall 3-phase KIPS program is described. This volume presents a program plan for qualifying the organic Rankine power system for flight test in 1982. The program plan calls for the design and fa… more
Date: March 15, 1978
Partner: UNT Libraries Government Documents Department
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Ultra-lightweight telescope with MEMS adaptive optic for distortion correction.

Description: Recent world events have underscored the need for a satellite based persistent global surveillance capability. To be useful, the satellite must be able to continuously monitor objects the size of a person anywhere on the globe and do so at a low cost. One way to satisfy these requirements involves a constellation of satellites in low earth orbit capable of resolving a spot on the order of 20 cm. To reduce cost of deployment, such a system must be dramatically lighter than a traditional satellit… more
Date: December 1, 2004
Creator: Spahn, Olga Blum; Cowan, William D.; Shaw, Michael J.; Adams, David Price; Sweatt, William C.; Dagel, Daryl James et al.
Partner: UNT Libraries Government Documents Department
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Extraordinary optical transmission through patterned subwavelength apertures.

Description: Light propagating through a subwavelength aperture can be dramatically increased by etching a grating in the metal around the hole. Moreover, light that would typically broadly diverge when passing through an unpatterned subwavelength hole can be directed into a narrow beam by utilizing a specific pattern around the aperture. While the increased transmission and narrowed angular emission appear to defy far-field diffraction theory, they are consistent with a fortuitous plasmon/photon coupling. … more
Date: December 1, 2004
Creator: Kemme, Shanalyn A.; El-Kady, Ihab Fathy; Hadley, G. Ronald; Peters, David William & Lanes, Chris E.
Partner: UNT Libraries Government Documents Department
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IRAS-based whole-sky upper limit on Dyson Spheres

Description: A Dyson Sphere is a hypothetical construct of a star purposely cloaked by a thick swarm of broken-up planetary material to better utilize all of the stellar energy. A clean Dyson Sphere identification would give a significant signature for intelligence at work. A search for Dyson Spheres has been carried out using the 250,000 source database of the IRAS infrared satellite which covered 96% of the sky. The search has used the Calgary data collection of the IRAS Low Resolution Spectrometer (LRS) … more
Date: September 1, 2008
Creator: Carrigan, Richard A., Jr.
Partner: UNT Libraries Government Documents Department
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Compositional Modulation in InxGa1-xN

Description: Transmission Electron Microscopy and x-ray diffraction were used to study compositional modulation in In{sub x}Ga{sub 1-x} N layers grown with compositions close to the miscibility gap. The samples (0.34 < x < 0.8) were deposited by molecular beam epitaxy using either a 200-nm-thick AlN or GaN buffer layer grown on a sapphire substrate. In the TEM imaging mode this modulation is seen as black/white fringes which can be considered as self-assembled thin quantum wells. Periodic compositiona… more
Date: July 20, 2005
Creator: Liliental-Weber, Z.; Zakharov, D. N.; Yu, K. M.; Ager, J. W., III; Walukiewicz, W.; Haller, E. E. et al.
Partner: UNT Libraries Government Documents Department
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Evidence for Merging or Disruption of Red Galaxies from the Evolution of Their Clustering

Description: The formation and evolution of massive red galaxies form a crucial test of theories of galaxy formation based on hierarchical assembly. In this Letter we use observations of the clustering of luminous red galaxies from the Boötes field and N-body simulations to argue that about of the most luminous satellite galaxies appear to undergo merging or disruption within massive halos between and 0.5.
Date: November 29, 2006
Creator: White, Martin; White, Martin; Zheng, Zheng; Brown, Michael J. I.; Dey, Arjun & Jannuzi, Buell T.
Partner: UNT Libraries Government Documents Department
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