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Book Review Geostatistical Analysis of Compositional Data

Description: Compositional data are represented as vector variables with individual vector components ranging between zero and a positive maximum value representing a constant sum constraint, usually unity (or 100 percent). The earth sciences are flooded with spatial distributions of compositional data, such as concentrations of major ion constituents in natural waters (e.g. mole, mass, or volume fractions), mineral percentages, ore grades, or proportions of mutually exclusive categories (e.g. a water-oil-r… more
Date: March 26, 2007
Creator: Carle, S F
Partner: UNT Libraries Government Documents Department
open access

Surface species formed by the adsorption and dissociation of water molecules on Ru(0001) surface containing a small coverage of carbon atoms studied by scanning tunneling microscopy

Description: The adsorption and dissociation of water on a Ru(0001) surface containing a small amount ({le} 3 %) of carbon impurities was studied by scanning tunneling microscopy (STM). Various surface species are formed depending on the temperature. These include molecular H{sub 2}O, H{sub 2}O-C complexes, H, O, OH and CH. Clusters of either pure H{sub 2}O or mixed H{sub 2}O-OH species are also formed. Each of these species produces a characteristic contrast in the STM images and can be identified by exper… more
Date: April 26, 2008
Creator: UCB, Dept of Materials Science and Engineering
Partner: UNT Libraries Government Documents Department
open access

Melting of bcc Transition Metals and Icosahedral Clustering

Description: In contrast to polyvalent metals, transition metals have low melting slopes(dT/dP) that are due to partially filled d-bands that allow for a lowering of liquid phase energy through s-d electron transfer and the formation of local structures. In the case of bcc transition metals we show the apparent discrepancy of DAC melting measurements with shock melting of Mo can be understood by reexamining the shock data for V and Ta and introducing the presence of an icosahedral short range order (ISRO) m… more
Date: May 26, 2006
Creator: Ross, M; Boehler, R & Japel, S
Partner: UNT Libraries Government Documents Department
open access

Characterization of an AO-OCT system

Description: Adaptive optics (AO) and optical coherence tomography (OCT) are powerful imaging modalities that, when combined, can provide high-volumetric-resolution, images of the retina. The AO-OCT system at UC Davis has been under development for 2 years and has demonstrated the utility of this technology for microscopic, volumetric, in vivo retinal imaging [1]. The current system uses an AOptix bimorph deformable mirror (DM) for low-order, high-stroke correction [2] and a 140-actuator Boston Micromachine… more
Date: July 26, 2007
Creator: Evans, J. W.; Zawadzki, R. J.; Jones, S.; Olivier, S. & Werner, J. S.
Partner: UNT Libraries Government Documents Department
open access

ELECTRICAL SAFETY IMPROVEMENT PROJECT A COMPLEX WIDE TEAMING INITIATIVE

Description: This paper describes the results of a year-long project, sponsored by the Energy Facility Contractors Group (EFCOG) and designed to improve overall electrical safety performance throughout Department of Energy (DOE)-owned sites and laboratories. As evidenced by focused metrics, the Project was successful primarily due to the joint commitment of contractor and DOE electrical safety experts, as well as significant support from DOE and contractor senior management. The effort was managed by an ass… more
Date: November 26, 2007
Creator: BJ, GRAY
Partner: UNT Libraries Government Documents Department
open access

Towards an Accurate Performance Modeling of Parallel SparseFactorization

Description: We present a performance model to analyze a parallel sparseLU factorization algorithm on modern cached-based, high-end parallelarchitectures. Our model characterizes the algorithmic behavior bytakingaccount the underlying processor speed, memory system performance, aswell as the interconnect speed. The model is validated using theSuperLU_DIST linear system solver, the sparse matrices from realapplications, and an IBM POWER3 parallel machine. Our modelingmethodology can be easily adapted to stud… more
Date: May 26, 2006
Creator: Grigori, Laura & Li, Xiaoye S.
Partner: UNT Libraries Government Documents Department
open access

Experimental characterization of initial conditions and spatio-temporal evolution of a small Atwood number Rayleigh-Taylor mixing layer

Description: The initial multi-mode interfacial velocity and density perturbations present at the onset of a small Atwood number, incompressible, miscible, Rayleigh-Taylor instability-driven mixing layer have been quantified using a combination of experimental techniques. The streamwise interfacial and spanwise interfacial perturbations were measured using high-resolution thermocouples and planar laser-induced fluorescence (PLIF), respectively. The initial multi-mode streamwise velocity perturbations at the… more
Date: September 26, 2005
Creator: Mueschke, N J; Andrews, M J & Schilling, O
Partner: UNT Libraries Government Documents Department
open access

Cobra-IE Evaluation by Simulation of the NUPEC BWR Full-Size Fine-Mesh Bundle Test (BFBT)

Description: The COBRA-IE computer code is a thermal-hydraulic subchannel analysis program capable of simulating phenomena present in both PWRs and BWRs. As part of ongoing COBRA-IE assessment efforts, the code has been evaluated against experimental data from the NUPEC BWR Full-Size Fine-Mesh Bundle Tests (BFBT). The BFBT experiments utilized an 8 x 8 rod bundle to simulate BWR operating conditions and power profiles, providing an excellent database for investigation of the capabilities of the code. Benchm… more
Date: April 26, 2006
Creator: Burns, C. J. and Aumiler, D. L.
Partner: UNT Libraries Government Documents Department
open access

Simulation of Wakefield Effect in ILC IR Chamber

Description: To achieve super high luminosity, high current beams with very short bunch length are needed, which carry high intensity EM fields. For ILC, two bunch trains with bunch length of 300 {micro}m and bunch charge of 3.2nC are needed to collide at the IR to achieve the ILC luminosity goals. When the 300 {micro}m bunches pass through the IR chamber, wakefields will be excited, which will cause HOM power flowing through the IR chamber beam pipe to the final doublets due to the high frequency character… more
Date: June 26, 2008
Creator: Pei, S; Seryi, A. & Raubenheimer, T.O.
Partner: UNT Libraries Government Documents Department
open access

Multiplexed Molecular Assays for Rapid Rule-Out of Foot-and-Mouth Disease

Description: A nucleic acid-based multiplexed assay was developed that combines detection of foot-and-mouth disease virus (FMDV) with rule-out assays for two other foreign animal diseases and four domestic animal diseases that cause vesicular or ulcerative lesions indistinguishable from FMDV infection in cattle, sheep and swine. The FMDV 'look-alike' diagnostic assay panel contains five PCR and twelve reverse transcriptase PCR (RT-PCR) signatures for a total of seventeen simultaneous PCR amplifications for … more
Date: June 26, 2007
Creator: Lenhoff, R; Naraghi-Arani, P; Thissen, J; Olivas, J; Carillo, C; Chinn, C et al.
Partner: UNT Libraries Government Documents Department
open access

High-Efficiency Solar Cells for Large-Scale Electricity Generation

Description: One strategy for helping the solar industry to grow faster is to use very high efficiency cells under concentrating optics. By using lenses or mirrors to concentrate the light, very small solar cells can be used, reducing the amount of semiconductor material and allowing use of higher efficiency cells, which are now >40% efficient.
Date: September 26, 2008
Creator: Kurtz, S.; Olson, J.; Geisz, J.; Friedman, D.; McMahon, W.; Ptak, A. et al.
Partner: UNT Libraries Government Documents Department
open access

EUV mask reflectivity measurements with micron-scale spatial resolution

Description: The effort to produce defect-free mask blanks for EUV lithography relies on increasing the detection sensitivity of advanced mask inspection tools, operating at several wavelengths. We describe the unique measurement capabilities of a prototype actinic (EUV wavelength) microscope that is capable of detecting small defects and reflectivity changes that occur on the scale of microns to nanometers. Types of defects: (a) Buried Substrate Defects: particles & pits (causes amplitude and/or phase vari… more
Date: May 26, 2008
Creator: Goldberg, Kenneth A.; Rekawa, S. B.; Kemp, C. D.; Barty, A.; Anderson, E. H.; Kearney, Patrick et al.
Partner: UNT Libraries Government Documents Department
open access

Colliding with a crunching bubble

Description: In the context of eternal inflation we discuss the fate of Lambda = 0 bubbles when they collide with Lambda< 0 crunching bubbles. When the Lambda = 0 bubble is supersymmetric, it is not completely destroyed by collisions. If the domain wall separating the bubbles has higher tension than the BPS bound, it is expelled from the Lambda = 0 bubble and does not alter its long time behavior. If the domain wall saturates the BPS bound, then it stays inside the Lambda = 0 bubble and removes a finite … more
Date: March 26, 2007
Creator: Freivogel, Ben; Freivogel, Ben; Horowitz, Gary T. & Shenker, Stephen
Partner: UNT Libraries Government Documents Department
open access

Beam Collimation Studies for the ILC Positron Source

Description: Results of the collimation studies for the ILC positron source beam line are presented. The calculations of primary positron beam loss are done using the ELEGANT code. The secondary positron and electron beam loss, the synchrotron radiation along the beam line and the bremsstrahlung radiation in the collimators are simulated using the STRUCT code. The first part of the collimation system, located right after the positron source target (0.125 GeV), is used for protection of the RF Linac sections… more
Date: June 26, 2008
Creator: Drozhdin, A.; Nosochkov, Y. & Zhou, F.
Partner: UNT Libraries Government Documents Department
open access

Green (2(omega)) Laser Beam propagation in high-temperature Hohlraum Plasmas

Description: We demonstrate propagation and small backscatter losses of a frequency-doubled (2{omega}) laser beam interacting with inertial confinement fusion hohlraum plasmas. The electron temperature of 3.3 keV, approximately a factor of two higher than achieved in previous experiments with open geometry targets, approaches plasma conditions of high-fusion yield hohlraums. In this new temperature regime, we measure 2{omega} laser beam transmission approaching 80% with simultaneous backscattering losses of… more
Date: October 26, 2007
Creator: Niemann, C; Berger, R; Divol, L; Froula, D H; Jones, O S; Kirkwood, R K et al.
Partner: UNT Libraries Government Documents Department
open access

Thoughts on Verification of Nuclear Disarmament

Description: It is my pleasure to be here to day to participate in this Conference. My thanks to the organizers for preparing such an interesting agenda on a very difficult topic. My effort in preparing my presentation was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48. And as many of you know Lawrence Livermore National Laboratory is now, as of Oct 1st, under contract to the Lawrence Livermore Na… more
Date: September 26, 2007
Creator: Dunlop, W H
Partner: UNT Libraries Government Documents Department
open access

Physics Design Requirements for the National Spherical Torus Experiment Liquid Lithium Divertor

Description: Recent NSTX high power divertor experiments have shown significant and recurring benefits of solid lithium coatings on PFC's to the performance of divertor plasmas in both L- and H- mode confinement regimes heated by high-power neutral beams. The next step in this work is installation of a liquid lithium divertor (LLD) to achieve density control for inductionless current drive capability (e.g., about a 15-25% ne decrease from present highest non-inductionless fraction discharges which often evo… more
Date: September 26, 2008
Creator: Kugel, W.; Bell, M.; Berzak,L.; Brooks, A.; Ellis, R.; Gerhardt, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Evaluating EUV mask pattern imaging with two EUV microscopes

Description: Aerial image measurement plays a key role in the development of patterned reticles for each generation of lithography. Studying the field transmitted (reflected) from EUV masks provides detailed information about potential disruptions caused by mask defects, and the performance of defect repair strategies, without the complications of photoresist imaging. Furthermore, by measuring the continuously varying intensity distribution instead of a thresholded, binary resist image, aerial image measure… more
Date: February 26, 2008
Creator: Goldberg, Kenneth A.; Takase, Kei; Naulleau, Patrick P.; Han, Hakseung; Barty, Anton; Kinoshita, Hiroo et al.
Partner: UNT Libraries Government Documents Department
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