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Simultaneous stabilization using genetic algorithms

Description: This paper considers the problem of simultaneously stabilizing a set of plants using full state feedback. The problem is converted to a simple optimization problem which is solved by a genetic algorithm. Several examples demonstrate the utility of this method. 14 refs., 8 figs.
Date: January 1, 1991
Creator: Benson, R.W. & Schmitendorf, W.E. (California Univ., Irvine, CA (USA). Dept. of Mechanical Engineering)
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Partner: UNT Libraries Government Documents Department
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Investigation of component failures in downhole geothermal pumping systems. Final report

Description: This study investigated component failures in electric, downhole submersible pumps which prevented the attainment of one year continuous downhole running times in geothermal wells at temperatures up to 375/sup 0/F. The feasibility of a pressurized motor to prevent brine intrusion was investigated, as well as improved pothead and packoff designs, and brine scale buildup on impeller sleeve bearings and thrust washers. (ACR)
Date: March 15, 1985
Creator: Werner, Douglas K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phase 2 of the array automated assembly task for the low cost solar array project. First annual report, October 1, 1977-October 30, 1978

Description: A process sequence has been proposed and tested for the fabrication of dendritic web silicon into solar modules. This sequence has been analyzed as to yield and cost and these data suggest that the price goals of 1986 are attainable. A number of the processes that make up this sequence have been further developed and studied as to cost reduction. Specifically, it has been shown that a low cost POCl/sub 3/ is a suitable replacement for the semiconductor grade, and that a suitable CVD oxide (eith… more
Date: November 16, 1978
Creator: Campbell, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Safety support for hydrogen reanalysis of Waste Tank 101-SY

Description: Tank 101-Sy, a double-shell tank on the Hanford SY high-level waste tank farm, has periodic releases of large volumes of gas. The released gas contains hydrogen (a fuel), nitrous oxide (a strong oxidizer), and other gases. These gases are intimately mixed, and therefore, it is very difficult to reduce the potential for a hydrogen combustion event. The safety is hydrogen gas exceeding one-quarter of the Lower Flammability Limit during these periodic releases. The Department of Energy Office of E… more
Date: January 1, 1991
Creator: Sullivan, L. H.; Eisenhawer, S. W.; Henninger, R. J.; Hill, S. W.; MacFarlane, D. R.; Nichols, B. D. et al.
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Partner: UNT Libraries Government Documents Department
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Effects of neutron irradiation on a superconducting metallic glass

Description: The effects of fast neutron irradiation on a superconducting metallic glass (Mo /sub 6/Ru /sub 4/)/sub 82/B/sub 18/ have been studied. Following irradiation to a total fluence of 10/sup 19/ n/cm/sup 2/, T/sub c/ increases from 6.05 K to 6.19 K, and the width of the transition decreases sharply. The density of the material decreases by 1.5%, and the x-ray scattering intensity maxima are broadened. An improvement in the ductility of the samples is observed which together with the other observatio… more
Date: June 1, 1979
Creator: Kramer, E. A.; Johnson, W. L. & Cline, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Low Noise Preamplifier for the Detection and Position Determination of Single Electrons in a Cerenkov Ring Imaging Detector by Charge Division

Description: A preamplifier having 500 electrons noise (rms) has been developed for the detection and location of single electrons in a CRID detector at the SLD. A single channel contains preamp, RC-CR shaper, gain adjustment, driver, and calibration circuitry. Noise and linearity measurements are presented.
Date: October 1, 1987
Creator: Spencer, E.; Coyle, P.; Williams, D.; Bienz, T.; Bird, F.; Gaillard, M. et al.
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Partner: UNT Libraries Government Documents Department
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A comparison of conventional and prototype nondestructive measurements on molten salt extraction residues

Description: Fourteen molten salt extraction residues were assayed by conventional and prototype nondestructive assay (NDA) techniques to be compared with destructive chemical analysis in an effort to identify acceptable NDA measurement methods for this matrix. NDA results on seven samples and destructive results on four samples are presented.
Date: January 1, 1987
Creator: Longmire, V. L.; Hurd, J. R.; Sedlacek, W. E. & Scarborough, A. M.
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Partner: UNT Libraries Government Documents Department
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Superspace WZW models and black holes

Description: We show how to write an off-shell action for the SU(2) x U(1) supersymmetric WZW model in terms of N = 2 chiral and twisted chiral multiplets. We discuss the N = 4 supersymmetry of this model and exhibit the N = 4 superconformal current algebra. Finally, we show that the off-shell formulation makes it possible to perform a duality transformation, which leads to a supersymmetric sigma model on a manifold with a black hole type singularity. 23 refs.
Date: October 1, 1991
Creator: Rocek, M. (Institute for Advanced Study, Princeton, NJ (United States). School of Natural Sciences); Ahn, C.; Schoutens, K. (State Univ. of New York, Stony Brook, NY (United States). Inst. for Theoretical Physics) & Sevrin, A. (Lawrence Berkeley Lab., CA (United States))
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Partner: UNT Libraries Government Documents Department
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Magnetic measurements of the XLS magnets

Description: The magnets designed and built for Phase 1 (200MeV) of the XLS (X-Ray Lithography Source) project have all been measured and characterized. In this paper, the measurement system designed and utilized for the Phase 1 180 degree dipole magnets is reviewed. Hall probe measurements of the two dipole magnets, with a field of 1.1 Tesla at 1200 amperes, are discussed and presented. Phase 2 (700MeV) of this project includes replacement of the two room temperature dipole magnets with superconducting dip… more
Date: January 1, 1991
Creator: Solomon, L.; Galayda, J. & Sylvester, C.
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Partner: UNT Libraries Government Documents Department
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Investigation of the chemistry of calcium carbonate scale nucleation and growth from seawater on OTEC heat exchangers

Description: The potential for calcium carbonate scale formation, from supersaturated seawater on candidate Ocean Thermal Energy Conversion heat exchanger tubes, has been tested under flowing and stagnant seawater, and leaking liquid ammonia conditions. It was not possible to confirm the existence of calcium carbonate in any of the deposits formed. However, the presence of calcium in the deposits, generally as a minor component, indicates that microcrystalline calcium carbonate may be formed. Tests performe… more
Date: August 1, 1979
Creator: Morse, J. W.; Brass, G. W.; Walter, L. M. & Van Valin, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Where does CBT (computer-based training) fit in, now that we know so much. A front end analysis study

Description: Computer-based training (CBT) has now been in existence for over two decades. It has been implemented in both the private sector and government organizations at an exponential rate. Nevertheless, many institutions, particularly educational institutions, have not yet introduced CBT. Our knowledge of what works and what does not, as well as hardware and software advances, has greatly increased in the past few years. This paper addresses many management considerations with respect to CBT. First, w… more
Date: January 1, 1987
Creator: Andrews, A. E. & Trainor, M. S.
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Partner: UNT Libraries Government Documents Department
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Three dimensional contact/impact methodology

Description: The simulation of three-dimensional interface mechanics between reactor components and structures during static contact or dynamic impact is necessary to realistically evaluate their structural integrity to off-normal loads. In our studies of postulated core energy release events, we have found that significant structure-structure interactions occur in some reactor vessel head closure designs and that fluid-structure interactions occur within the reactor vessel. Other examples in which three-di… more
Date: January 1, 1987
Creator: Kulak, R.F.
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Partner: UNT Libraries Government Documents Department
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Fuel plantation research. Progress report

Description: Research in chemical induction of lightwood is summarized. Four large-scale proof of concept studies have been installed that test five paraquat treatments on a total of 71,228 trees. This wood will be used in actual pulp mill and extraction plant runs to determine oleoresin recovery and possible processing problems. Nearly 3,000 wood samples have been collected to ascertain duration of treatment effects. Results of complementary studies are also reported; most of these are concerned with optim… more
Date: August 1, 1977
Creator: Stubbs, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of thermomechanical treatment on phase stability and swelling in alloy D9

Description: Improvement in the swelling of AISI 316 may be achieved through adjustments to levels of Ni, Cr, Mo, Ti, and Si. Effort is concerned with optimizing the composition range for greater phase stability and improving alloy homogeneity. Irradiation response to variations in thermomechanical treatment (TMT) was studied. Swelling peak is suppressed by TMT which produces a high dislocation density or by increasing the solution treatment temperature to 1200/sup 0/C. (FS)
Date: January 1, 1979
Creator: Lee, E.H. & Rowcliffe, A.F.
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Partner: UNT Libraries Government Documents Department
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Tritium compatibility of alumina and Fosterite

Description: Many pressure measurements are required to control processing of the fuel gases associated with fusion power reactors. Since most pressure transducers respond to changes in pressure sensitive electrical parameters, insulators will be required to withstand chronic exposures to concentrated tritium. For this investigation samples of alumina and Fosterite were exposed to concentrated tritium gas for 11 weeks. Gas phase impurities were then analyzed for clues that would indicate decomposition of th… more
Date: September 1, 1979
Creator: Coffin, D.O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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344 cm x 86 cm low mass vacuum window

Description: The LBL Heavy Ion Spectrometer System (HISS) superconducting magnet contains a 1 m x 3.45 m x 2 m vacuum tank in its gap. A full aperture thin window was needed to minimize background as the products of nuclear collisions move from upstream targets to downstream detectors. Six windows were built and tested in the development process. The final window's unsupported area is 3m/sup 2/ with a 25 cm inward deflection. The design consists of a .11 mm Nylon/aluminum/polypropylene laminate as a gas sea… more
Date: August 1983
Creator: Reimers, R.M.; Porter, J.; Meneghetti, J.; Wilde, S. & Miller, R.
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Partner: UNT Libraries Government Documents Department
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Technical progress report of biological research on the Volcanic Island Surtsey and its environs for the period 1965--1978

Description: Progress is reported on the following research projects: changes in shoreline and surface of the island due to volcanic activity; colonization of microorganisms, algae, lichens, and vascular plants; introduction of insects and other arthropods by wind, water, and man; transport of invertebrates to the island by flotsam of the sea; species and nesting habits of birds on the island; behavior of seals on beaches of the island; and future trends of Surtsey ecosystems. (HLW)
Date: January 1, 1978
Creator: Fridriksson, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of the helium-jet fed on-line mass separator RAMA and its application to studies of T/sub z/ = -2 nuclei

Description: The study of nuclei far from beta stability is hampered greatly when the nuclide of interest decays in a manner identical to that of a nuclide produced in greater yield in the same bombardment. One solution to this problem is through the use of an on-line mass separator. Development of the Berkelely helium-jet fed on-line mass separator RAMA is discussed as applied to studies of the A = 4n, T/sub z/ = -2 nuclides. RAMA (Recoil Atom Mass Analyzer) has typical efficiencies of 0.1% for approx. 75 … more
Date: October 1, 1979
Creator: Moltz, D.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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1-GWh diurnal load-leveling superconducting magnetic energy storage system reference design. Appendix D: superconductive magnetic energy storage cavern construction methods and costs

Description: The excavation and preparation of an underground cavern to contain a 1-GWh diurnal load-leveling Superconducting Magnetic Energy Storage (SMES) unit is examined. The cavern's principal function is to provide a rock structure for supporting the magnetic forces from the charged storage coil. Certain economic considerations indicate the refrigerator cold box for the helium system should also be underground. The study includes such a provision and considers, among other things, rock bolting, water … more
Date: September 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Perturbative QCD: an overview

Description: Recent progress in the utilization of perturbative quantum chromodynamics to study lepton-hadron and hadron-hadron reactions is reviewed. Interest is focused on the connections between the various results and the implications for the parton model as a phenomenological tool and as a vehicle to test quantum chromodynamics. 42 references.
Date: January 1, 1979
Creator: Ellis, S.D.
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Partner: UNT Libraries Government Documents Department
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Friction factor correlation for 217 pin wire-wrap spaced LMFBR fuel assemblies

Description: Data from four independent water flow tests of 217 pin wire wrap spaced LMFBR fuel assemblies were analyzed and a friction factor correlation was developed. The data show that the mean friction factor varied little from one test to the next and the test statistics show that at a 3sigma confidence level, the uncertainty of predicting the friction factor is less than 1.7% from Reynolds numbers of 1000 to 100,000.
Date: April 1, 1981
Creator: Spencer, D.R. & Markley, R.A.
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Partner: UNT Libraries Government Documents Department
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Strength vs toughness relation in Fe-high manganese alloys

Description: Charpy impact tests were performed on the 16 to 36 wt % Mn steels whose tensile properties have already been reported. The effect of Mn content on the ductile-brittle transition behavior was basically identical with other workers' results. However, since the reasons for these phenomena are quite unclear, advanced experimental facts are discussed.
Date: April 1, 1984
Creator: Tomota, Y. & Morris, J.W. Jr.
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Partner: UNT Libraries Government Documents Department
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Training of LBL-SSC model dipole magnets at 1. 8 K

Description: We present the 1.8K training behavior of SSC Magnets, several of which have reached a peak current of 9400 A; a central field of 9 Tesla. For the SSC Project, more than 30 one meter long dipole magnets have been built and tested. The test results for the 4.3K operation have been presented previously. Magnet operation, primarily reaching design field without premature training, is expected to be superior in superfluid helium at 1.8K as compared with helium I at 4.3K. Not only is the critical cur… more
Date: March 1, 1989
Creator: Gilbert, W.S.; Althaus, R.; Benjegerdes, R.; Caspi, S.; Peters, C.; Rechen, J. et al.
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Partner: UNT Libraries Government Documents Department
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Long-term observations of Cyg X-3 with Vela 5B

Description: We present long-term (1969 to 1979) observations of Cygnus X-3, obtained by the Vela 5B satellite. The 3 to 12 keV light curve has 10 day time resolution. Cyg X-3 is a peculiar high-luminosity x-ray source, radiating from the radio region to hard gamma rays of more than 10/sup 16/ eV. It has a 4.8 hour period, probably orbital, which is not resolved by our present analysis. Long-term periodicities of approx. 17, 20, and 33 to 34 days have been reported by several authors, and explained as the e… more
Date: January 1, 1984
Creator: Priedhorsky, W.
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Partner: UNT Libraries Government Documents Department
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