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Local Effects of Biased Electrodes in the Divertor of NSTX

Description: The goal of this paper is to characterize the effects of small non-axisymmetric divertor plate electrodes on the local scrape-off layer plasma. Four small rectangular electrodes were installed into the outer divertor plates of NSTX. When the electrodes were located near the outer divertor strike point and biased positively, there was an increase in the nearby probe currents and probe potentials and an increase in the LiI light emission at the large major radius end of these electrodes. When an electrode located farther outward from the outer divertor strike point was biased positively, there was sometimes a significant decrease in the LiI light emission at the small major radius end of this electrode, but there were no clear effects on the nearby probes. No non-local effects were observed with the biasing of these electrodes.
Date: May 7, 2012
Creator: : S. Zweben, M.D. Campanell, B.C. Lyons, R.J. Maqueda, Y. Raitses, A.L. Roquemore and F. Scotti
Partner: UNT Libraries Government Documents Department
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Can Data Recognize Its Parent Distribution?

Description: This study is concerned with model selection of lifetime and survival distributions arising in engineering reliability or in the medical sciences. We compare various distributions, including the gamma, Weibull and lognormal, with a new distribution called geometric extreme exponential. Except for the lognormal distribution, the other three distributions all have the exponential distribution as special cases. A Monte Carlo simulation was performed to determine sample sizes for which survival distributions can distinguish data generated by their own families. Two methods for decision are by maximum likelihood and by Kolmogorov distance. Neither method is uniformly best. The probability of correct selection with more than one alternative shows some surprising results when the choices are close to the exponential distribution.
Date: May 1, 1999
Creator: A.W.Marshall; J.C.Meza & Olkin, and I.
Partner: UNT Libraries Government Documents Department
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Microstructure, Phase Formation, and Stress of Reactively-Deposited Metal Hydride Thin Films

Description: This document summarizes research of reactively deposited metal hydride thin films and their properties. Reactive deposition processes are of interest, because desired stoichiometric phases are created in a one-step process. In general, this allows for better control of film stress compared with two-step processes that react hydrogen with pre-deposited metal films. Films grown by reactive methods potentially have improved mechanical integrity, performance and aging characteristics. The two reactive deposition techniques described in this report are reactive sputter deposition and reactive deposition involving electron-beam evaporation. Erbium hydride thin films are the main focus of this work. ErH{sub x} films are grown by ion beam sputtering erbium in the presence of hydrogen. Substrates include a Al{sub 2}O{sub 3} {l_brace}0001{r_brace}, a Al{sub 2}O{sub 3} {l_brace}1120{r_brace}, Si{l_brace}001{r_brace} having a native oxide, and polycrystalline molybdenum substrates. Scandium dideuteride films are also studied. ScD{sub x} is grown by evaporating scandium in the presence of molecular deuterium. Substrates used for scandium deuteride growth include single crystal sapphire and molybdenum-alumina cermet. Ultra-high vacuum methods are employed in all experiments to ensure the growth of high purity films, because both erbium and scandium have a strong affinity for oxygen. Film microstructure, phase, composition and stress are evaluated using a number of thin film and surface analytical techniques. In particular, we present evidence for a new erbium hydride phase, cubic erbium trihydride. This phase develops in films having a large in-plane compressive stress independent of substrate material. Erbium hydride thin films form with a strong <111> out-of-plane texture on all substrate materials. A moderate in-plane texture is also found; this crystallographic alignment forms as a result of the substrate/target geometry and not epitaxy. Multi-beam optical sensors (MOSS) are used for in-situ analysis of erbium hydride and scandium hydride film stress. These instruments probe the evolution of film stress during all …
Date: May 1, 2002
Creator: ADAMS, DAVID P.; ROMERO, JUAN A.; RODRIGUEZ, MARK A.; FLORO, JERROLD A. & KOTULA, PAUL G.
Partner: UNT Libraries Government Documents Department
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[Monthly financial report, May 31, 1989]

Description: A financial statement from the AIDS Resource Center for the AIDS ARMS Network, Inc., dated May 31, 1989.
Date: May 31, 1989
Creator: AIDS ARMS Network, Inc.
Partner: UNT Libraries Special Collections
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Representative volume size: A comparison of statistical continuum mechanics and statistical physics

Description: In this combination background and position paper, the authors argue that careful work is needed to develop accurate methods for relating the results of fine-scale numerical simulations of material processes to meaningful values of macroscopic properties for use in constitutive models suitable for finite element solid mechanics simulations. To provide a definite context for this discussion, the problem is couched in terms of the lack of general objective criteria for identifying the size of the representative volume (RV) of a material. The objective of this report is to lay out at least the beginnings of an approach for applying results and methods from statistical physics to develop concepts and tools necessary for determining the RV size, as well as alternatives to RV volume-averaging for situations in which the RV is unmanageably large. The background necessary to understand the pertinent issues and statistical physics concepts is presented.
Date: May 1, 1999
Creator: AIDUN,JOHN B.; TRUCANO,TIMOTHY G.; LO,CHI S. & FYE,RICHARD M.
Partner: UNT Libraries Government Documents Department
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Cloud to CAD

Description: This paper documents work performed to convert scanned range data to CAD solid model representation. The work successfully developed surface fitting algorithms for quadric surfaces (e.g. plane, cone, cylinder, and sphere), and a segmentation algorithm based entirely on surface type, rather than on a differential metric like Gaussian curvature. Extraction of all CAD-required parameters for quadric surface representation was completed. Approximate face boundaries derived from the original point cloud were constructed. Work to extrapolate surfaces, compute exact edges and solid connectivity was begun, but left incomplete due to funding reductions. The surface fitting algorithms are robust in the face of noise and degenerate surface forms.
Date: May 1, 2001
Creator: AMES,ARLO L.
Partner: UNT Libraries Government Documents Department
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Feasibility of creating a new liquid surface within waste storage tank 241-SY-101

Description: The purpose of this study is to determine the feasibility of creating a new liquid surface within Waste Storage Tank 241-SY-101. This study looked at alternatives for this, as well as providing a summary of observations regarding water lancing results relative to this task.
Date: May 13, 1999
Creator: ANDRES, B.D.
Partner: UNT Libraries Government Documents Department
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Blade Manufacturing Improvement: Remote Blade Manufacturing Demonstration

Description: The objective of this program was to investigate manufacturing improvements for wind turbine blades. The program included a series of test activities to evaluate the strength, deflection, performance, and loading characteristics of the prototype blades. The original contract was extended in order to continue development of several key blade technologies identified in the project. The objective of the remote build task was to demonstrate the concept of manufacturing wind turbine blades at a temporary manufacturing facility in a rural environment. TPI Composites successfully completed a remote manufacturing demonstration in which four blades were fabricated. The remote demonstration used a manufacturing approach which relied upon material ''kits'' that were organized in the factory and shipped to the site. Manufacturing blades at the wind plant site presents serious logistics difficulties and does not appear to be the best approach. A better method appears to be regional manufacturing facilities, which will eliminate most of the transportation cost, without incurring the logistical problems associated with fabrication directly onsite. With this approach the remote facilities would use commonly available industrial infrastructure such as enclosed workbays, overhead cranes, and paved staging areas. Additional fatigue testing of the M20 root stud design was completed with good results. This design provides adhesive bond strength under fatigue loading that exceeds that of the fastener. A new thru-stud bonding concept was developed for the M30 stud design. This approach offers several manufacturing advantages; however, the test results were inconclusive.
Date: May 1, 2003
Creator: ASHWILL, THOMAS D.
Partner: UNT Libraries Government Documents Department
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Cost Study for Large Wind Turbine Blades

Description: The cost study for large wind turbine blades reviewed three blades of 30 meters, 50 meters, and 70 meters in length. Blade extreme wind design loads were estimated in accordance with IEC Class I recommendations. Structural analyses of three blade sizes were performed at representative spanwise stations assuming a stressed shell design approach and E-glass/vinylester laminate. A bill of materials was prepared for each of the three blade sizes using the laminate requirements prepared during the structural analysis effort. The labor requirements were prepared for twelve major manufacturing tasks. TPI Composites developed a conceptual design of the manufacturing facility for each of the three blade sizes, which was used for determining the cost of labor and overhead (capital equipment and facilities). Each of the three potential manufacturing facilities was sized to provide a constant annual rated power production (MW per year) of the blades it produced. The cost of the production tooling and overland transportation was also estimated. The results indicate that as blades get larger, materials become a greater proportion of total cost, while the percentage of labor cost is decreased. Transportation costs decreased as a percentage of total cost. The study also suggests that blade cost reduction efforts should focus on reducing material cost and lowering manufacturing labor, because cost reductions in those areas will have the strongest impact on overall blade cost.
Date: May 1, 2003
Creator: ASHWILL, THOMAS D.
Partner: UNT Libraries Government Documents Department
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Laser Safety Audit and Inventory System Database

Description: A laser safety auditing and inventory system has been in use at Sandia National Laboratories--Albuquerque for the past five years and has recently been considered for adoption by Sandia National Laboratories--Livermore. The system utilizes the ''Microsoft Access'' database application, part of the Office 2000 software package. Audit and inventory data is available on-line for ready access by laser users. Data is updated weekly to provide users with current information relating to laser facility audits and laser inventories.
Date: May 1, 2003
Creator: AUGUSTONI, ARNOLD L.
Partner: UNT Libraries Government Documents Department
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The comparison of element partitioning in two types of thermal treatment facilities and the effects on potential radiation dose

Description: The US Department of Energy (DOE) is performing a technical analysis to support the potential development of risk-based, numerical radiological control criteria (RCC) for mixed waste from DOE operations. As part of the technical analysis, potential future radiation doses are being calculated for workers at thermal treatment facilities and members of the public residing near such facilities. This study compared two types of thermal treatment systems: a conventional combustion chamber with excess air, represented by a rotary kiln with afterburner, and an oxygen-deficient pyrolysis unit, represented by a plasma arc furnace. The purpose of the first part of this study is to estimate the partitioning for significant radionuclides and elements in the two types of thermal treatment systems. Excess-air systems are generally found to produce heavy-metal chlorides, oxides, and sulfates; plasma-arc systems tend to produce more volatile free metals. This difference causes a change in source term dominance from halide volatility to free metal volatility. Chemical thermodynamic methodology is used to estimate partitioning in the two treatment systems. The second part of the study examines how the potential radiation dose to workers handling residue materials is affected by partitioning of radionuclides at the different types of facilities.
Date: May 1, 1995
Creator: Aaberg, R. L.; Burger, L. L.; Baker, D. A.; Wallo, A., III; Vazquez, G. A. & Beck, W. L.
Partner: UNT Libraries Government Documents Department
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ALARA Analysis of Radiological Control Criteria Associated with Alternatives for Disposal of Hazardous Wastes

Description: This ALARA analysis of Radiological Control Criteria (RCC) considers alternatives to continued storage of certain DOE mixed wastes. It also considers the option of treating hazardous wastes generated by DOE facilities, which have a very low concentration of radionuclide contaminants, as purely hazardous waste. Alternative allowable contaminant levels examined correspond to doses to an individual ranging from 0.01 mrem/yr to 10 to 20 mrem/yr. Generic waste inventory data and radionuclide source terms are used in the assessment. Economic issues, potential health and safety issues, and qualitative factors relating to the use of RCCs are considered.
Date: May 15, 2002
Creator: Aaberg, Rosanne L.; Bilyard, Gordon R.; Branch, Kristi M.; Lavender, Jay C. & Miller, Peter L.
Partner: UNT Libraries Government Documents Department
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Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization.

Description: A variety of edge joints utilizing a continuous wave Nd:YAG laser have been produced and examined in a 304-L stainless steel to advance fundamental understanding of the linkage between processing and resultant microstructure in high-rate solidification events. Acquisition of three-dimensional reconstructions via micro-computed tomography combined with traditional metallography has allowed for qualitative and quantitative characterization of weld joints in a material system of wide use and broad applicability. The presence, variability and distribution of porosity, has been examined for average values, spatial distributions and morphology and then related back to fundamental processing parameters such as weld speed, weld power and laser focal length.
Date: May 1, 2012
Creator: Aagesen, Larry K. & Madison, Jonathan D.
Partner: UNT Libraries Government Documents Department
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Uranium hydrogeochemical and stream sediment reconnaissance in Lincoln and Flathead Counties, northwest Montana

Description: Between mid-May and late June 1976, 3409 water and water-transported sediment samples were collected from 1781 locations spread over an approximate 17000-km/sup 2/ area of northwestern Montana. All of the samples were analyzed for total uranium at the LASL, using standardized procedures and rigorous quality controls, the waters by fluorometry and the sediment (and those waters with greater than 10 ppb uranium) by delayed-neutron counting methods. All of the field collection, treatment, and packaging of the samples was performed following strict LASL specifications. The uranium concentrations measured in the waters range from undetectable (less than 0.2) ppb to 173.6 ppb, but average only 0.66 ppb. The low uranium concentrations in the waters of this area are thought to be due primarily to a general lack of readily soluble uranium and dilution with spring runoff. Those locations which did have abnormally high uranium were examined more closely, and follow-up field examinations are recommended in the vicinity of some of these sites. The uranium content of the sediment samples range from 0.5 ppM to 52.2 ppM and average 4.56 ppM. Sample locations with high and/or anomalous uranium values were examined with respect to the local geology, water chemistry, and other relevant factors. A distinct correlation between the high uranium in sediment and epithermal and mesothermal veins associated with nearby faults and folds is evident at several locations. Areas believed to be favorable for follow-up field investigations based on the sediment data are indicated. A correlation between high uranium in water and high uranium in sediment is evident at only a single location. The generally low uranium concentrations in water and moderate concentrations in sediment seem to indicate that most of the uranium that does exist in this area is bound up in resistant minerals.
Date: May 1, 1977
Creator: Aamodt, P. L.
Partner: UNT Libraries Government Documents Department
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Uranium hydrogeochemical and stream sediment reconnaissance data from the area of the Noatak and portions of the Baird Mountains and Ambler River Quadrangles, Alaska

Description: During August 1976, a total of 876 natural waters and 861 bottom sediments were collected at a nominal density of one location each 23 km/sup 2/ from streams and small lakes throughout the Noatak NTMS quadrangle, the southern two-thirds of the Baird Mountains NTMS quadrangle, and in the southwest corner of the Ambler River NTMS quadrangle. These samples were collected as part of the National Uranium Resource Evaluation program in Alaska being conducted by the Los Alamos Scientific Laboratory (LASL). The field collection and treatment of the samples were performed following strict LASL specifications. Total uranium was measured in the waters by fluorometry and in the sediments by delayed-neutron counting, using stringent quality assurance controls at the LASL. The uranium contents of the waters ranged from below the detection limit of 0.02 parts per billion (ppB) to a high of 8.38 ppB, and the uranium contents of the sediments ranged from a low of 0.3 parts per million (ppM) to a high of 34.0 ppM. In general, the locations of waters containing relatively high uranium contents were found to occur in clusters, and particularly in the headwaters of streams draining the southern slopes of the Baird Mountains. Few sediments contained relatively high uranium contents. These usually occurred singly at isolated locations scattered throughout the area. No obvious association exists between the location of high-uranium waters and sediments anywhere in the study area. The geology, mineralogy, and hydrology of this area is only generally described in the literature; therefore, it is difficult to correlate these data with particular aspects of the physical environment where individual samples were collected. However, the data do indicate that certain areas underlaid by Paleozoic sedimentary rocks and granitic intrusives within the Baird Mountains and a quartz-pebble conglomerate in the Waring Mountains may warrant more detailed field …
Date: May 1, 1978
Creator: Aamodt, P.L.; Hill, D.E. & Sharp, R.R. Jr.
Partner: UNT Libraries Government Documents Department
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Uranium Hydrogeochemical and Stream Sediment Reconnaissance in Lincoln and Flathead Counties, Northwest Montana

Description: From abstract: Between mid-May and late June 1976, 3409 water and water-transported sediment samples were collected from 1781 locations spread over an approximate 17 000 kilometer area of northwestern Montana. All of the samples were analyzed for total uranium at the LASL, using standardized procedures and rigorous quality controls--the waters by fluorometry and the sediment (and those waters with >10 parts per billion uranium) by delayed-neutron counting methods.
Date: May 1977
Creator: Aamodt, Paul L.
Partner: UNT Libraries Government Documents Department
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Uranium Hydrogeochemical and Stream Sediment Reconnaissance Data from the Area of the Noatak and Portions of the Baird Mountains and Ambler River Quadrangles, Alaska

Description: From introduction: This report describes work done in the Noatak and portions of the Baird Mountains and Ambler River, Alaska, National Topographic Map Series (NTMS) quadrangles (1:250 000 scale) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).
Date: May 1978
Creator: Aamodt, Paul L.; Hill, Dwight E. & Sharp, Robert R., Jr.
Partner: UNT Libraries Government Documents Department
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