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A Parallel Multigrid Method for the Finite Element Analysis of Mechanical Contact

Description: A geometrical multigrid method for solving the linearized matrix equations arising from node-on-face three-dimensional finite element contact is described. The development of an efficient implementation of this combination that minimizes both the memory requirements and the computational cost requires careful construction and storage of the portion of the coarse mesh stiffness matrices that are associated with the contact stiffness on the fine mesh. The multigrid contact algorithm is paralleliz… more
Date: March 21, 2002
Creator: Hales, J. D. & Parsons, I. D.
Item Type: Refine your search to only Report
open access

An Examination of the Effects of Be Grain Size

Description: During the WBS4 review almost a year ago in January, and in more recent discussions of needed capsule characterization, I was struck by three pieces of information related to machined Be capsules: (1) that the speed of sound (and perhaps other properties) in Be grains is markedly different in orthogonal directions, (2) that the grain size in the best refined bulk Be samples is 10 to 15 {micro}m, and that these grains in the best case are randomly oriented, and (3) that we are concerned about ca… more
Date: November 21, 2000
Creator: Cook, R
Item Type: Refine your search to only Report
open access

A Revised Magnitude and Distance Amplitude Correction (MDAC2) Procedure for Regional Seismic Discriminants: Theory and Testing at NTS

Description: The Magnitude and Distance Amplitude Correction (MDAC; Taylor and Hartse, 1998; Taylor et al., 2002) procedure for correcting regional seismic amplitudes for seismic event identification has been modified to include more realistic earthquake source models and source scaling. In the MDAC2 formulation we generalize the Brune (1970) earthquake source spectrum to use a more physical apparent stress model that can represent non-constant stress-drop scaling. We also event include a parameter that all… more
Date: December 21, 2001
Creator: Walter, W R & Taylor, S R
Item Type: Refine your search to only Report
open access

Probability Density and CFAR Threshold Estimation for Hyperspectral Imaging

Description: The work reported here shows the proof of principle (using a small data set) for a suite of algorithms designed to estimate the probability density function of hyperspectral background data and compute the appropriate Constant False Alarm Rate (CFAR) matched filter decision threshold for a chemical plume detector. Future work will provide a thorough demonstration of the algorithms and their performance with a large data set. The LASI (Large Aperture Search Initiative) Project involves instrumen… more
Date: September 21, 2004
Creator: Clark, G A
Item Type: Refine your search to only Report
open access

Speckle Imaging Over Horizontal Paths

Description: Atmospheric aberrations reduce the resolution and contrast in surveillance images recorded over horizontal or slant paths. This paper describes our recent horizontal and slant path imaging experiments of extended scenes as well as the results obtained using speckle imaging. The experiments were performed with an 8-inch diameter telescope placed on either a rooftop or hillside and cover ranges of interest from 0.5 km up to 10 km. The scenery includes resolution targets, people, vehicles, and oth… more
Date: May 21, 2002
Creator: Carrano, C J
Item Type: Refine your search to only Article
open access

FUDGE: A Program for Performing Nuclear Data Testing and Sensitivity Studies

Description: We have developed a program called FUDGE that allows one to modify data from LLNL's nuclear database. After modifying data, FUDGE can then be instructed to process the data into the formats used by LLNL's deterministic (ndf) and the Monte Carlo (MCAPM) transport codes. This capability allows users to perform nuclear data sensitivity studies without modification of the transport modeling codes. FUDGE is designed to be user friendly (object-oriented) and fast (the modification and processing typi… more
Date: September 21, 2004
Creator: Beck, B R
Item Type: Refine your search to only Article
open access

Edge Plasma Analysis for Liquid-wall MFE Concepts

Description: A thick flowing layer of liquid (e.g., flibe-a molten salt, or Sn{sub 80}Li{sub 20}--a liquid metal) protects the structural walls of the magnetic fusion configuration so that they can last the life of the plant even with intense 14 MeV neutron bombardment from the D-T fusion reaction, The surface temperature of the liquid rises as it passes from the inlet nozzles to the exit nozzles due to absorption of line and bremsstrahlung radiation, and neutrons. The surface temperature can be reduced by … more
Date: September 21, 2000
Creator: Moir, R W; Rensink, M & Rognlien, T D
Item Type: Refine your search to only Article
open access

Infrared Spectra of High Pressure Carbon Monoxide

Description: We report infrared (IR) spectroscopic measurements of carbon monoxide (CO) at high pressures. Although CO is one of the simplest heteronuclear diatomic molecules, it displays surprisingly complex behavior at high pressures and has been the subject of several studies [1-5]. IR spectroscopic studies of high pressures phases of CO provide data complementing results from previous studies and elucidating the nature of these phases. Though a well-known and widely utilized diagnostic of molecular syst… more
Date: September 21, 2001
Creator: Evans, W. J.; Lipp, M. J. & Lorenzana, H. E.
Item Type: Refine your search to only Article
open access

Neutrino Factory and Beta Beam Experiments and Development.

Description: The long-term prospects for fully exploring three-flavor mixing in the neutrino sector depend upon an ongoing and increased investment in the appropriate accelerator R&D. Two new concepts have been proposed that would revolutionize neutrino experiments, namely the Neutrino Factory and the Beta Beam facility. These new facilities would dramatically improve our ability to test the three-flavor mixing framework, measure CP violation in the lepton sector, and perhaps determine the neutrino mass… more
Date: September 21, 2004
Creator: Albright, C.; Berg, J. S.; Fernow, R.; Gallardo, J.; Kahn, S.; Kirk, H. et al.
Item Type: Refine your search to only Report
open access

Blue and Green Light? Wavelength Scaling for NIF

Description: Use of the National Ignition Facility to also output frequency-doubled (.53{micro}m) laser light would allow significantly more energy to be delivered to targets as well as significantly greater bandwidth for beam smoothing. This green light option could provide access to new ICF target designs and a wider range of plasma conditions for other applications. The wavelength scaling of the interaction physics is a key issue in assessing this green light option. Wavelength scaling theory based on th… more
Date: August 21, 2003
Creator: Suter, L.; Miller, M.; Moody, J. & Kruer, W.
Item Type: Refine your search to only Article
open access

Coarse-Grained Molecular Dynamics and Multiscale Modeling of NEMS Resonators

Description: We review concurrent multiscale simulations of dynamic and temperature-dependent processes found in nanomechanical systems coupled to larger scale surroundings. We focus on the behavior of sub-micron Micro-Electro-Mechanical Systems (MEMS), especially microresonators. These systems are often called NEMS, for Nano-Electro-Mechanical Systems. The coupling of length scales methodology we have developed for MEMS employs an atomistic description of small but key regions of the system, consisting of … more
Date: December 21, 2001
Creator: Rudd, R E
Item Type: Refine your search to only Article
open access

A Rule-Based Framework for Gene Regulation Pathways Discovery

Description: We present novel approach to discover the rules that govern gene regulation mechanisms. The method is based on supervised machine learning and is designed to reveal relationships between transcription factors and gene promoters. As the representation of the gene regulatory circuit we have chosen a special form of IF-THEN rules associating certain features (a generalized idea of a Transcription Factor Binding Site) in gene promoters with specific gene expression profiles.
Date: July 21, 2003
Creator: Wilczynski, B; Hvidsten, T; Kryshtafovych, A; Stubbs, L; Komorowski, J & Fidelis, K
Item Type: Refine your search to only Article
open access

Heats of Formation of Energetic Oxetane Monomers and Polymers

Description: Energetic oxetane polymers have shown promise as performance-enhancing ingredients in gun and missile propellants. In order to correctly predict the performance of energetic materials containing these polymers, it is important to have accurate, experimentally determined values for the polymer heats of formation ({Delta}H{sub f}). In support of a theoretical study on gun propellant performance, heats of combustion were experimentally determined for a series of oxetane polymers and monomers (see … more
Date: March 21, 2001
Creator: Schmidt, R D & Manser, G E
Item Type: Refine your search to only Article
open access

An Integrated Universal Collapsar Gamma-ray Burst Model

Description: Starting with two assumptions: (1) gamma-ray bursts originate from stellar death phenomena or so called ''collapsars'' and (2) that these bursts are quasi-universal, whereby the majority of the observed variation is due to our perspective of the jet, an integrated gamma-ray burst model is proposed. It is found that several of the key correlations in the data can be naturally explained with this simple picture and another possible correlation is predicted.
Date: January 21, 2004
Creator: Salmonson, J D
Item Type: Refine your search to only Article
open access

Segregation of Uranium Metal from K Basin Sludge: Results from Vendor Testing

Description: Under contract to Fluor Hanford, Pacific Northwest National Laboratory directed laboratory, bench-scale, and pilot-scale vendor testing to evaluate the use of commercial gravity mineral concentration technology to remove and concentrate uranium metal from Hanford K Basin sludge. Uranium metal in the sludge corrodes by reacting with water to generate heat and hydrogen gas, and may constrain shipment and disposal of the sludge to the Waste Isolation Pilot Plant as remote-handled transuranic waste… more
Date: September 21, 2004
Creator: Schmidt, Andrew J.; Elmore, Monte R. & Delegard, Calvin H.
Item Type: Refine your search to only Report
open access

Final Report West Valley High-Level Waste Tank Lay-Up

Description: This report documents completion of Milestone A.4-1 "Issue Tank Lay-Up Strategies for WVDP Final Report," in Technical Task Plan RL3-WT21A, "Post-Retrieval and Pre-Closure HLW Tank Lay-Up." This task was a collaborative effort among Pacific Northwest National Laboratory, Jacobs Engineering Group Inc., and West Valley Nuclear Services. The primary objective of the overall task was to develop and evaluate conceptual strategies for preclosure lay-up of the two large high-level waste storage tanks … more
Date: June 21, 2002
Creator: Elmore, Monte R. & Henderson, Colin
Item Type: Refine your search to only Report
open access

Laser- and Radar-based Mission Concepts for Suborbital and Spaceborne Monitoring of Seismic Surface Waves

Description: The development of a suborbital or spaceborne system to monitor seismic waves poses an intriguing prospect for advancing the state of seismology. This capability would enable an unprecedented global mapping of the velocity structure of the earth's crust, understanding of earthquake rupture dynamics and wave propagation effects, and event source location, characterization and discrimination that are critical for both fundamental earthquake research and nuclear non-proliferation applications. As … more
Date: September 21, 2004
Creator: Foxall, W; Schultz, C A & Tralli, D M
Item Type: Refine your search to only Article
open access

The Factory Approach to Creating TSTT Meshes

Description: The factory approach (a.k.a. virtual constructor) hides the details of the class implementing the TSTT from TSTT users. In version 0.5 of TSTT.sidl, the client hard codes the name of the implementing class into their code. The client is forced to choose from the small set of possible concrete classes defined in TSTT.sidl. This approach makes it impossible to support multiple implementations of the TSTT in a single process because each implementation has to implement the same class. The factory … more
Date: October 21, 2003
Creator: Epperly, T
Item Type: Refine your search to only Report
open access

MATRIX PRODUCT VARIATIONAL FORMULATION FOR LATTICE GAUGE THEORY.

Description: For hamiltonian lattice gauge theory, we introduce the matrix product ansatz inspired from density matrix renormalization group. In this method, wavefunction of the target state is assumed to be a product of finite matrices. As a result, the energy becomes a simple function of the matrices, which can be evaluated using a computer. The minimum of the energy function corresponds to the vacuum state. We show that the S = 1/2 Heisenberg chain model are well described with the ansatz. The method is … more
Date: September 21, 2004
Creator: SUGIHARA,T.
Item Type: Refine your search to only Article
open access

Surface Dynamics during Environmental Degradation of Crystal Surfaces

Description: Using in situ optical microscopy and scattering measurements, we have followed the evolution of surface morphology during etching and measured surface etching rates as a function of humidity and undersaturation. From our experiments to date we have developed the following picture of etch pit formation on KDP crystal surfaces. Pit formation is characterized by a nucleation and growth process: the introduction of water creates a condition of undersaturation at the crystal surface. The equilibrium… more
Date: February 21, 2001
Creator: Whitman, P; DeYoreo, J; Land, T; Miller, E; Suratwala, T; Thorsness, C et al.
Item Type: Refine your search to only Report
open access

Calibration of Regional Seismic Stations in the Middle East with Shots in Turkey

Description: The objective of this project is to calibrate regional travel-times and propagation characteristics of seismic waves in Turkey and surrounding areas in the Middle East in order to enhance detection and location capabilities in the region. Important data for the project will be obtained by large calibration shots in central and eastern Turkey. The first, a two-ton shot, was fired in boreholes near Keskin in central Anatolia on 23 November 2002. The explosives were placed in 14 holes, each 80 m d… more
Date: July 21, 2003
Creator: Toksoz, M N; Kuleli, S; Gurbuz, C; Kalafat, D; Nekler, T; Zor, K et al.
Item Type: Refine your search to only Article
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