UNT Libraries Government Documents Department - 30,711 Matching Results

Search Results

open access

Empirical Study of Ne in H-Mode Pedestal in DIII-D

Description: There is compelling empirical [1] and theoretical [2] evidence that the global confinement of H-mode discharges increases as the pedestal pressure or temperature increases. Therefore, confidence in the performance of future machines requires an ability to predict the pedestal conditions in those machines. At this time, both the theoretical and empirical understanding of transport in the pedestal are incomplete and are inadequate to predict pedestal conditions in present or future machines. Receā€¦ more
Date: May 5, 2005
Creator: . Groebner, R. J.; Osborne, T. H.; Fenstermacher, M. E.; Leonard, A. W.; Mahdavi, M. A.; Snyder, P. B. et al.
open access

Cost-Effective Silicon Wafers for Solar Cells

Description: Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program for hydrogen fuel cell vehicles (project title "Direct Wafer Enabling Terawatt Photovoltaics") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: 1366 Technologies, Inc.
open access

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 ā€¦ more
Date: May 7, 2012
Creator: : S. Zweben, M.D. Campanell, B.C. Lyons, R.J. Maqueda, Y. Raitses, A.L. Roquemore and F. Scotti
open access

Epicyclic Twin-helix Magnetic Structure for Parametric-resonance Ionization Cooling

Description: ParaĀ­metĀ­ric-resĀ­oĀ­nance IonĀ­izaĀ­tion CoolĀ­ing (PIC) is enĀ­viĀ­sioned as the final 6D coolĀ­ing stage of a high-luĀ­miĀ­nosĀ­iĀ­ty muon colĀ­lidĀ­er. ImĀ­pleĀ­mentĀ­ing PIC imĀ­posĀ­es strinĀ­gent conĀ­straints on the coolĀ­ing chanĀ­nel's magĀ­netĀ­ic opĀ­tics deĀ­sign. This paper preĀ­sents a linĀ­ear opĀ­tics soĀ­luĀ­tion comĀ­patĀ­iĀ­ble with PIC. Our soĀ­luĀ­tion conĀ­sists of a suĀ­perĀ­poĀ­siĀ­tion of two opĀ­poĀ­site-heĀ­licĀ­iĀ­ty equal-peĀ­riĀ­od and equal-strength heĀ­liĀ­cal dipole harĀ­monĀ­ics and a straight norĀ­mal quadrupoleā€¦ more
Date: May 1, 2010
Creator: A. Afanasev, R.P. Johnson, Y.S. Derbenev, V.S. Morozov
open access

Shielding of a hadron in a finite e-beam

Description: The thorough study of coherent electron cooling, the modern cooling technique capable to deal with accelerators operating in the range of few TeVs, rises many interesting questions. One of them is a shielding dynamics of a hadron in an electron beam. Now this effect is computed analytically in the infinite beam approximation. Many effects are drastically different in finite and infinite plasmas. Here we propose a method to compute the dynamical shielding effect in a finite cylindrical plasma - ā€¦ more
Date: May 20, 2012
Creator: A., Elizarov; Litvinenko, V. & Wang, G.
open access

Progress of Bep Treatments on Nb at JLAB

Description: Recent experimental results have indicated that Buffered Electropolishing (BEP) is a promising candidate for the next generation of surface treatment technique for Nb superconducting radio frequency (SRF) cavities to be used in particle accelerators. In order to lay the foundation for using BEP as the next generation surface treatment technique for Nb SRF cavities, some fundamental aspects of BEP treatments for Nb have to be investigated. In this report, recent progress on BEP study at JLab is ā€¦ more
Date: May 1, 2010
Creator: A.T. Wu, S. Jin, R.A. Rimmer,X.Y. Lu, K. Zhao
open access

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 disā€¦ more
Date: May 1, 1999
Creator: A.W.Marshall; J.C.Meza & Olkin, and I.
open access

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 reacā€¦ more
Date: May 1, 2002
Creator: ADAMS, DAVID P.; ROMERO, JUAN A.; RODRIGUEZ, MARK A.; FLORO, JERROLD A. & KOTULA, PAUL G.
open access

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 theā€¦ more
Date: May 1, 1999
Creator: AIDUN,JOHN B.; TRUCANO,TIMOTHY G.; LO,CHI S. & FYE,RICHARD M.
open access

Molecular dynamic simulations, {sup 6}Li solid state NMR and ultraphosphate glasses

Description: The author's laboratory continues to use NMR to investigate the structure and dynamics in amorphous materials, including the local structure of ultraphosphate glasses. Changes in the alkali environment in these phosphate glasses as a function of modifier concentration has recently been probed using {sup 6}Li and {sup 23}Na solid state NMR. Molecular dynamic (MD) simulations have also been performed in an attempt to gain additional insight into the variations of the local structure. Interestinglā€¦ more
Date: May 1, 2000
Creator: ALAM,TODD M.
open access

THERMAL CONDUCTIVITY AND OTHER PROPERTIES OF CEMENTITIOUS GROUTS

Description: The thermal conductivity and other properties cementitious grouts have been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. In addition to thermal conductivity, the cementitious grouts were also tested for bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotheā€¦ more
Date: May 1, 1998
Creator: ALLAN,M.
open access

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 cā€¦ more
Date: May 1, 2001
Creator: AMES,ARLO L.
open access

Use of inelastic analysis in cask design

Description: In this paper, the advantages and disadvantages of inelastic analysis are discussed. Example calculations and designs showing the implications and significance of factors affecting inelastic analysis are given. From the results described in this paper it can be seen that inelastic analysis provides an improved method for the design of casks. It can also be seen that additional code and standards work is needed to give designers guidance in the use of inelastic analysis. Development of these codā€¦ more
Date: May 15, 2000
Creator: AMMERMAN,DOUGLAS J. & BREIVIK,NICOLE L.
Back to Top of Screen