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Accelerator R&D: Research for Science - Science for Society (open access)

Accelerator R&D: Research for Science - Science for Society

None
Date: October 7, 2013
Creator: White, M.; Ozaki, S.; Biedron, S.; Milton, S. V.; Hoffstaetter, G. H.; Henderson, S. et al.
System: The UNT Digital Library
Advanced Drilling through Diagnostics-White-Drilling (open access)

Advanced Drilling through Diagnostics-White-Drilling

A high-speed data link that would provide dramatically faster communication from downhole instruments to the surface and back again has the potential to revolutionize deep drilling for geothermal resources through Diagnostics-While-Drilling (DWD). Many aspects of the drilling process would significantly improve if downhole and surface data were acquired and processed in real-time at the surface, and used to guide the drilling operation. Such a closed-loop, driller-in-the-loop DWD system, would complete the loop between information and control, and greatly improve the performance of drilling systems. The main focus of this program is to demonstrate the value of real-time data for improving drilling. While high-rate transfer of down-hole data to the surface has been accomplished before, insufficient emphasis has been placed on utilization of the data to tune the drilling process to demonstrate the true merit of the concept. Consequently, there has been a lack of incentive on the part of industry to develop a simple, low-cost, effective high-speed data link. Demonstration of the benefits of DWD based on a high-speed data link will convince the drilling industry and stimulate the flow of private resources into the development of an economical high-speed data link for geothermal drilling applications. Such a downhole communication …
Date: October 7, 1999
Creator: Finger, John T.; Glowka, David Anthony; Livesay, Billy Joe; Mansure, Arthur J. & Prairie, Michael R.
System: The UNT Digital Library
Advances in atmospheric chemistry modeling: the LLNL impact tropospheric/stratospheric chemistry model (open access)

Advances in atmospheric chemistry modeling: the LLNL impact tropospheric/stratospheric chemistry model

We present a unique modeling capability to understand the global distribution of trace gases and aerosols throughout both the troposphere and stratosphere. It includes the ability to simulate tropospheric chemistry that occurs both in the gas phase as well as on the surfaces of solid particles. We have used this capability to analyze observations from particular flight campaigns as well as averaged observed data. Results show the model to accurately simulate the complex chemistry occurring near the tropopause and throughout the troposphere and stratosphere.
Date: October 7, 1999
Creator: Rotman, D A & Atherton, C
System: The UNT Digital Library
Aerogel commercialization: Technology, markets and costs (open access)

Aerogel commercialization: Technology, markets and costs

Commercialization of aerogels has been slow due to several factors including cost and manufacturability issues. The technology itself is well enough developed as a result of work over the past decade by an international-community of researchers. Several extensive substantial markets appear to exist for aerogels as thermal and sound insulators, if production costs can keep prices in line with competing established materials. The authors discuss here the elements which they have identified as key cost drivers, and they give a prognosis for the evolution of the technology leading to reduced cost aerogel production.
Date: October 7, 1994
Creator: Carlson, G.; Lewis, D.; McKinley, K.; Richardson, J. & Tillotson, T.
System: The UNT Digital Library
AFM CHARACTERIZATION OF RAMAN LASER INDUCED DAMAGE ON CDZNTECRYSTAL SURFACES (open access)

AFM CHARACTERIZATION OF RAMAN LASER INDUCED DAMAGE ON CDZNTECRYSTAL SURFACES

High quality CdZnTe (or CZT) crystals have the potential for use in room temperature gamma-ray and X-ray spectrometers. Over the last decade, the methods for growing high quality CZT have improved the quality of the produced crystals however there are material features that can influence the performance of these materials as radiation detectors. The presence of structural heterogeneities within the crystals, such as twinning, pipes, grain boundaries (polycrystallinity), and secondary phases (SPs) can have an impact on the detector performance. There is considerable need for reliable and reproducible characterization methods for the measurement of crystal quality. With improvements in material characterization and synthesis, these crystals may become suitable for widespread use in gamma radiation detection. Characterization techniques currently utilized to test for quality and/or to predict performance of the crystal as a gamma-ray detector include infrared (IR) transmission imaging, synchrotron X-ray topography, photoluminescence spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Raman spectroscopy. In some cases, damage caused by characterization methods can have deleterious effects on the crystal performance. The availability of non-destructive analysis techniques is essential to validate a crystal's quality and its ability to be used for either qualitative or quantitative gamma-ray or X-ray detection. The …
Date: October 7, 2008
Creator: Teague, L. & Duff, M.
System: The UNT Digital Library
Analysis of three-phase power-supply systems using computer-aided design programs (open access)

Analysis of three-phase power-supply systems using computer-aided design programs

A major concern of every designer of large, three-phase power-supply systems is the protection of system components from overvoltage transients. At present, three computer-aided circuit design programs are available in the Magnetic Fusion Energy (MFE) National Computer Center that can be used to analyze three-phase power systems: MINI SCEPTRE, SPICE I, and SPICE II. These programs have been used at Lawrence Livermore Laboratory (LLL) to analyze the operation of a 200-kV dc, 20-A acceleration power supply for the High Voltage Test Stand. Various overvoltage conditions are simulated and the effectiveness of system protective devices is observed. The simulated overvoltage conditions include such things as circuit breaker openings, pulsed loading, and commutation voltage surges in the rectifiers. These examples are used to illustrate the use of the computer-aided, circuit-design programs discussed in this paper.
Date: October 7, 1977
Creator: Oberst, E.F.
System: The UNT Digital Library
ARAC: A flexible real-time dose consequence assessment system (open access)

ARAC: A flexible real-time dose consequence assessment system

Since its beginning, the Atmospheric Release Advisory Capability (ARAC), an emergency radiological dose assessment service of the US Government, has been called on to do consequence assessments for releases into the atmosphere of radionuclides and a variety of other substances. Some of the more noteworthy emergency responses have been for the Three Mile Island and Chernobyl nuclear power reactor accidents, and more recently, for a cloud of gases from a rail-car spill into the Sacramento river of the herbicide metam sodium, smoke from hundreds of burning oil wells in Kuwait, and ash clouds from the eruption of Mt. Pinatubo. The spatial scales of these responses range from local, to regional, to global, and the response periods from hours, to weeks, to months. Because of the variety of requirements of each unique assessment, ARAC has developed and maintains a flexible system of people, computer software and hardware.
Date: October 7, 1993
Creator: Ellis, J. S. & Sullivan, T. J.
System: The UNT Digital Library
Automated supernova search (open access)

Automated supernova search

A program is described for development of an automated supernova search based upon complete remote computer control of a telescope and vidicon digital imaging system. (GHT)
Date: October 7, 1981
Creator: Colgate, S. A.
System: The UNT Digital Library
B physics in Run II (open access)

B physics in Run II

Run II at the Tevatron started on March 1, 2001 with a design instantaneous luminosity of 2 x 10{sup 32} cm{sup -2} s{sup -1}. The upgraded D0 detector is expected to collect 2 fb{sup -1} of data at {radical}s = 2.0 TeV in approximately 2 years. The D0 collaboration is planning to make measurements in a number of important areas of B physics, including sin(2{beta}), B{sub s} mixing, the {Lambda}{sub b} lifetime and rare B decays. In this note we describe the upgraded D0 detector and highlights of the B physics program in D0.
Date: October 7, 2002
Creator: Kuznetsov, Valentin E
System: The UNT Digital Library
Baryon-strangeness correlations: a diagnostic of stronglyinteracting matter (open access)

Baryon-strangeness correlations: a diagnostic of stronglyinteracting matter

The correlation between baryon number and strangeness elucidates the nature of strongly interacting matter. This diagnostic can be extracted theoretically from lattice QCD calculations and experimentally from event-by-event fluctuations. The analysis of present lattice results above the critical temperature severely limits the presence of q{bar q} bound states, thus supporting a picture of independent (quasi)quarks. Details may be found in [1].
Date: October 7, 2005
Creator: Koch, Volker; Majumder, Abhijit & Randrup, Jorgen
System: The UNT Digital Library
Baseline Design of the SuperB Factory Injection System (open access)

Baseline Design of the SuperB Factory Injection System

None
Date: October 7, 2013
Creator: Bacci, A.; Biagini, M. E.; Boni, R.; Boscolo, M.; Guiducci, S.; Preger, M. A. et al.
System: The UNT Digital Library
Best Practices for Information Architecture, Organization, and Retrieval in Digital Language Archives within University Institutional Repositories (open access)

Best Practices for Information Architecture, Organization, and Retrieval in Digital Language Archives within University Institutional Repositories

Article highlighting a case study about building a working digital language archive in a hosted university institutional repository. It was presented at the 1st International Workshop on Digital Language Archives held on September 30-October 1, 2021 as part of the ACM/IEEE Joint Conference on Digital Libraries 2021.
Date: October 7, 2021
Creator: Vann, Robert E.
System: The UNT Digital Library
The BFKL Equation, Mueller-Navelet Jets and Single-valued Harmonic Polylogarithms (open access)

The BFKL Equation, Mueller-Navelet Jets and Single-valued Harmonic Polylogarithms

None
Date: October 7, 2013
Creator: Del Duca, Vittorio; Dixon, Lance J.; Duhr, Claude & Pennington, Jeffrey
System: The UNT Digital Library
Cable-in-conduit conductor optimization for fusion magnet applications (open access)

Cable-in-conduit conductor optimization for fusion magnet applications

Careful design of the toroidal-field (TF) and poloidal-field (PF) coils in a tokamak machine using cable-in-conduit conductors (CICC) can result in quite high overall winding-pack current densities - even with the high nuclear heat loads that may be imposed in operating a fusion reactor - and thereby help reduce the overall machine size. In our design process, we systematically examined the operational environment of a magnet, e.g., mechanical stresses, current, field, heat load, coolant temperature, and cooldown stresses, to determine the optimum amounts of copper, superconductor, helium, and sheath material for the CICC. This process is being used to design the superconducting magnet systems that comprise the Tokamak Ignition/Burn Experimental Reactor (TIBER II). 13 refs., 2 figs.
Date: October 7, 1987
Creator: Miller, J. R. & Kerns, J. A.
System: The UNT Digital Library
CDF Status and B Physics Prospects (open access)

CDF Status and B Physics Prospects

With extensive upgrades to the detector and electronics, CDF has started collecting data with Run II of the Tevatron. The enhanced silicon coverage and the use of silicon based tracks in the trigger, make CDF well suited for a broad program of B hadron measurements. We present the current status of the experiment and prospects for measurements in Run II.
Date: October 7, 2002
Creator: Miller, J. Stephen
System: The UNT Digital Library
Challenges in Heritage Language Documentations: BraPoRus, Spoken Corpus of Heritage Russian in Brazil (open access)

Challenges in Heritage Language Documentations: BraPoRus, Spoken Corpus of Heritage Russian in Brazil

Article describing the BRAzilian POrtuguese RUSsian Corpus (BraPoRus), a corpus that consists of multiple speech samples of older Russian heritage speakers in Brazil, and discussing the best ways to make these data available in the forms that satisfy the requirements both for the linguistic and sociological research. It was presented at the 1st International Workshop on Digital Language Archives held on September 30-October 1, 2021 as part of the ACM/IEEE Joint Conference on Digital Libraries 2021.
Date: October 7, 2021
Creator: Smirnova Henriques, Anna; Skorobogatova, Aleksandra S.; Ruseishvili, Svetlana; Madureira, Sandra & Sekerina, Irina A.
System: The UNT Digital Library
Challenges to Representing Personal Names and Language Names in Language Archives: Examples from Northeast India (open access)

Challenges to Representing Personal Names and Language Names in Language Archives: Examples from Northeast India

Article reviewing one particular challenge to data management relevant to South Asia, which is the complexity of names (of individuals, groups, and languages). It was presented at the 1st International Workshop on Digital Language Archives held on September 30-October 1, 2021 as part of the ACM/IEEE Joint Conference on Digital Libraries 2021.
Date: October 7, 2021
Creator: Burke, Mary & Chelliah, Shobhana Lakshmi
System: The UNT Digital Library
Characterization of Spatial Heterogenieties in Detector Grade CdZnTe (open access)

Characterization of Spatial Heterogenieties in Detector Grade CdZnTe

This report talks about Characterization of Spatial Heterogenieties in Detector Grade CdZnTe.
Date: October 7, 2007
Creator: Duff, M
System: The UNT Digital Library
Characterization of the Effect of Au/Al Bondpad Corrosion on Microelectronic Device Reliability (open access)

Characterization of the Effect of Au/Al Bondpad Corrosion on Microelectronic Device Reliability

A methodology has been established to predict the effect of atmospheric corrosion on the reliability of plastic encapsulated microelectronic (PEM) devices. New experimental techniques were developed to directly characterize the Al/Au wirebond interface where corrosion primarily occurs. A deterministic empirical model describing wirebond degradation as a function of environmental conditions was generated. To demonstrate how this model can be used to determine corrosion effects on device reliability, a numerical simulation was performed on a three-lead voltage reference device. Surface reaction rate constants, environmental variables and the defect characteristics of the encapsulant were treated as distributed parameters. A Sandia-developed analytical framework (CRAX{trademark}) was used to include uncertainty in the analysis and directly calculate reliability.
Date: October 7, 1999
Creator: Braithwaite, Jeffrey W.; Michael, Joseph R.; Peterson, David W.; Robinson, David G.; Sorensen, Neil R. & Strizich, M. P.
System: The UNT Digital Library
Coffinitization of Uraninite: SEM/AEM Investigation and Geochemical Modeling (open access)

Coffinitization of Uraninite: SEM/AEM Investigation and Geochemical Modeling

Coffinite (USiO{sub 4}) has been found in numerous sedimentary and hydrothermal environments including those considered as natural analogues of nuclear waste repositories. Scanning electron microscopy (SEM) and analytical electron microscopy (AEM) studies have been conducted on a uraninite sample from a U-deposit in Canada. It is observed that the uraninite (UO{sub 2+x}) is replaced by coffinite (U[SiO{sub 4}].nH{sub 2}O) and the replacing coffinite coexists with quartz. The TEM study shows {alpha}-recoil damage, lattice distortion, and low-angle boundaries among neighboring uraninite domains. Coffinitization seems more closely associated with {alpha}-recoil-damaged uraninite areas. Electron energy-loss spectroscopy (EELS) spectrum indicates that the ratio of U(+6)U(+4) in the uraninite is about 2/3, while the coffinite is dominated by U(+4). A thermodynamic calculation indicates that coffinitization can take place most likely at temperatures below 130 C if dissolved silica concentrations are limited by amorphous silica mineral phase. In a sufficiently high silica concentration environment, coffinite can form under the oxygen fugacity of 10{sup -65}-10{sup -55} atm. The equilibrium model, however, is not able to explain the coexistence of coffinite with quartz. A kinetic model that takes account of Ostwald processes is thus proposed. The kinetic model indicates that the presence of U(+6) in uraninite and the …
Date: October 7, 1999
Creator: Wang, Yifeng & Xu, Huifang
System: The UNT Digital Library
Collaborating with Language Community Members to Enrich Ethnographic Descriptions in a Language Archive (open access)

Collaborating with Language Community Members to Enrich Ethnographic Descriptions in a Language Archive

Article describing a pilot project undertaken at the Computational Resource for South Asian Languages (CoRSAL) which explores a collaborative archiving approach to enable language community members to tell their own stories by adding contextual information to archival materials. It was presented at the 1st International Workshop on Digital Language Archives held on September 30-October 1, 2021 as part of the ACM/IEEE Joint Conference on Digital Libraries 2021.
Date: October 7, 2021
Creator: Burke, Mary
System: The UNT Digital Library
A Combinatorial Approach to Determine Mechanisms of Atmospheric Copper Sulfidation (open access)

A Combinatorial Approach to Determine Mechanisms of Atmospheric Copper Sulfidation

Parallel microscopic experimentation (the combinatorial approach often used in solid-state science) was applied to characterize atmospheric copper corrosion behavior. Specifically, this technique permitted relative sulfidation rates to be determined for copper containing different levels of point defects and impurities (In, Al, O, and D). Corrosion studies are inherently difficult because of complex interactions between material interfaces and the environment. The combinatorial approach was demonstrated using micron-scale Cu lines that were exposed to a humid air environment containing sub-ppm levels of H{sub 2}S. The relative rate of Cu{sub 2}S growth was determined by measuring the change in resistance of the line. The data suggest that vacancy trapping by In and Al impurities slow the sulfidation rate. Increased sulfidation rates were found for samples containing excess point defects or deuterium. Furthermore, the sulfidation rate of 14 {micro}m wide Cu lines was increased above that for planar films.
Date: October 7, 1999
Creator: Barbour, J. Charles; Braithwaite, Jeffrey W.; Copeland, Robert Guild; Dunn, Roberto G.; Minor, Kenneth G.; Missert, Nancy A. et al.
System: The UNT Digital Library
Computational Chemical Dynamics: From Gas- Phase to Condensed - Phase Systems (Poster Book) (open access)

Computational Chemical Dynamics: From Gas- Phase to Condensed - Phase Systems (Poster Book)

None
Date: October 7, 2004
Creator: Cramer, Christopher J.
System: The UNT Digital Library
A Constrained Standard Model: Effects of Fayet-Iliopoulos Terms (open access)

A Constrained Standard Model: Effects of Fayet-Iliopoulos Terms

In [1]the one Higgs doublet standard model was obtained by an orbifold projection of a 5D supersymmetric theory in an essentially unique way, resulting in a prediction for the Higgs mass m_H = 127 +- 8 GeV and for the compactification scale 1/R = 370 +- 70 GeV. The dominant one loop contribution to the Higgs potential was found to be finite, while the above uncertainties arose from quadratically divergent brane Z factors and from other higher loop contributions. In [3], a quadratically divergent Fayet-Iliopoulos term was found at one loop in this theory. We show that the resulting uncertainties in the predictions for the Higgs boson mass and the compactification scale are small, about 25percent of the uncertainties quoted above, and hence do not affect the original predictions. However, a tree level brane Fayet-Iliopoulos term could, if large enough, modify these predictions, especially for 1/R.
Date: October 7, 2001
Creator: Barbieri, Riccardo; Hall, Lawrence J. & Nomura, Yasunori
System: The UNT Digital Library