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The MTX (Microwave Tokamak Experiment) data acquisition system

Description: The diagnostic data from the MTX experiment is acquired and processed by an expandable, distributed, multivendor computer network. The system blends a variety of software into a coordinated, unified, and highly flexible design. Using modular software design techniques, we created a system stressing distributed processing, portability, and transparent data access. In our approach to modularity, we standardized communication interfaces between modules and separated generic tasks from machine and … more
Date: September 20, 1989
Creator: Butner, D. N.; Drlik, M.; Brown, M. D.; Casper, T. A.; Meyer, W. H. & Moller, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Program RELAX: A code designed to calculate atomic relaxation spectra of x-rays and electrons

Description: The code RELAX is designed to calculate atomic relaxation spectra of X-rays and electrons due to bound-bound transitions. This calculation is based on the atomic transition data contained in the Livermore Evaluated Atomic Data Library (EADL). The results produced by this code for fluorescence yield vs. atomic number (Z) have been published in Tables and Graphs of Atomic Subshell and Relaxation Data Derived from the LLNL Evaluated Atomic Data Library (EADL), z = 1--100{double prime}, UCRL-50400,… more
Date: March 20, 1992
Creator: Cullen, D.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Radio-loud high-redshift protogalaxy canidates in Bootes

Description: We used the Near Infrared Camera (NIRC) on Keck I to obtain K{sub s}-band images of four candidate high-redshift radio galaxies selected using optical and radio data in the NOAO Deep Wide-Field Survey in Bootes. Our targets have 1.4 GHz radio flux densities greater than 1 mJy, but are undetected in the optical. Spectral energy distribution fitting suggests that three of these objects are at z > 3, with radio luminosities near the FR-I/FR-II break. The other has photometric redshift z{sub pho… more
Date: July 20, 2007
Creator: Croft, S.; van Breugel, W.; Brown, M. J.; de Vries, W.; Dey, A.; Eisenhardt, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Climate Modeling using High-Performance Computing

Description: The Center for Applied Scientific Computing (CASC) and the LLNL Climate and Carbon Science Group of Energy and Environment (E&E) are working together to improve predictions of future climate by applying the best available computational methods and computer resources to this problem. Over the last decade, researchers at the Lawrence Livermore National Laboratory (LLNL) have developed a number of climate models that provide state-of-the-art simulations on a wide variety of massively parallel … more
Date: April 20, 2006
Creator: Mirin, A. A. & Wickett, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mobile Data Collection Applications: A Proof of Concept

Description: This project's goal is to provide a proof of concept for mobile data collection applications, and identify the best ways such applications could be implemented and used. Such an application should decrease the time and resources users now need to devote to redundant data processes, and provide an easy of locating and retrieving data at a later time. The two types of available mobile devices, Personal Digital Assistants and Tablet Personal Computers, each have their particular strengths that sug… more
Date: September 20, 2006
Creator: Chang, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Structures in Molecular Clouds: Modeling

Description: We attempt to predict the observed morphology, column density and velocity gradient of Pillar II of the Eagle Nebula, using Rayleigh Taylor (RT) models in which growth is seeded by an initial perturbation in density or in shape of the illuminated surface, and cometary models in which structure is arises from a initially spherical cloud with a dense core. Attempting to mitigate suppression of RT growth by recombination, we use a large cylindrical model volume containing the illuminating source a… more
Date: April 20, 2006
Creator: Kane, J. O.; Mizuta, A.; Pound, M. W.; Remington, B. A. & Ryutov, D. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Characterization of Direct Push Vadose Zone Sediments from the 241-U Single-Shell Tank Farm

Description: The overall goals of the Tank Farm Vadose Zone Project, led by CH2M HILL Hanford Group, Inc., are 1) to define risks from past and future single-shell tank farm activities, 2) to identify and evaluate the efficacy of interim measures, and 3) to aid, via collection of geochemical information and data, the future decisions that must be made by the U.S. Department of Energy (DOE) regarding the near-term operations, future waste retrieval, and final closure activities for the single-shell tank Wast… more
Date: December 20, 2007
Creator: Brown, Christopher F.; Valenta, Michelle M.; Serne, R. Jeffrey; Bjornstad, Bruce N.; Lanigan, David C.; Iovin, Cristian et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CORBA-Based Distributed Software Framework for the NIF Integrated Computer Control System

Description: The National Ignition Facility (NIF), currently under construction at the Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8 Megajoule, 500-Terawatt, ultra-violet laser system together with a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. The NIF is operated by the Integrated Computer Control System (ICCS) which is a scalable, framework-based control system distributed over 800 computers throughout the NIF. The fra… more
Date: November 20, 2007
Creator: Stout, E A; Carey, R W; Estes, C M; Fisher, J M; Lagin, L J; Mathisen, D G et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

"Eztrack": A single-vehicle deterministic tracking algorithm

Description: A variety of surveillance operations require the ability to track vehicles over a long period of time using sequences of images taken from a camera mounted on an airborne or similar platform. In order to be able to see and track a vehicle for any length of time, either a persistent surveillance imager is needed that can image wide fields of view over a long time-span or a highly maneuverable smaller field-of-view imager is needed that can follow the vehicle of interest. The algorithm described … more
Date: December 20, 2007
Creator: Carrano, C J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Corporate Functional Management Evaluation of the LLNL Radiation Safety Organization

Description: A Corporate Assess, Improve, and Modernize review was conducted at Lawrence Livermore National Laboratory (LLNL) to evaluate the LLNL Radiation Safety Program and recommend actions to address the conditions identified in the Internal Assessment conducted July 23-25, 2007. This review confirms the findings of the Internal Assessment of the Institutional Radiation Safety Program (RSP) including the noted deficiencies and vulnerabilities to be valid. The actions recommended are a result of intervi… more
Date: March 20, 2008
Creator: Sygitowicz, L S
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Applied Focused Ion Beam Techniques for Sample Preparation of Astromaterials for Integrated Nano-Analysis

Description: Sample preparation is always a critical step in study of micrometer sized astromaterials available for study in the laboratory, whether their subsequent analysis is by electron microscopy or secondary ion mass spectrometry. A focused beam of gallium ions has been used to prepare electron transparent sections from an interplanetary dust particle, as part of an integrated analysis protocol to maximize the mineralogical, elemental, isotopic and spectroscopic information extracted from one individu… more
Date: February 20, 2007
Creator: Graham, G A; Teslich, N E; Kearsley, A T; Stadermann, F J; Stroud, R M; Dai, Z R et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A fourth order accurate adaptive mesh refinement method forpoisson's equation

Description: We present a block-structured adaptive mesh refinement (AMR) method for computing solutions to Poisson's equation in two and three dimensions. It is based on a conservative, finite-volume formulation of the classical Mehrstellen methods. This is combined with finite volume AMR discretizations to obtain a method that is fourth-order accurate in solution error, and with easily verifiable solvability conditions for Neumann and periodic boundary conditions.
Date: August 20, 2004
Creator: Barad, Michael & Colella, Phillip
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

NARAC SOFTWARE QUALITY ASSURANCE: ADAPTING FORMALISM TO MEET VARYING NEEDS

Description: The National Atmospheric Release Advisory Center (NARAC) provides tools and services that predict and map the spread of hazardous material accidentally or intentionally released into the atmosphere. NARAC is a full function system that can meet a wide range of needs with a particular focus on emergency response. The NARAC system relies on computer software in the form of models of the atmosphere and related physical processes supported by a framework for data acquisition and management, user in… more
Date: November 20, 2007
Creator: Walker, H; Nasstrom, J S & Homann, S G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Probing the Universe with Mirrors That Trick Light

Description: For astrophysicists, stargazing may be different than for most people, who are content to admire a star's beauty or possibly make a wish. More than a few astrophysicists wish they could be closer to the stars--or to at least have more sophisticated probing instruments--to understand more about the universe. Astrophysicists study x-rays originating from our Sun, stars, and supernova remnants to understand the extreme physical processes occurring there. In recent years, Livermore researchers have… more
Date: September 20, 2005
Creator: Hazi, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Speech recognition systems on the Cell Broadband Engine

Description: In this paper we describe our design, implementation, and first results of a prototype connected-phoneme-based speech recognition system on the Cell Broadband Engine{trademark} (Cell/B.E.). Automatic speech recognition decodes speech samples into plain text (other representations are possible) and must process samples at real-time rates. Fortunately, the computational tasks involved in this pipeline are highly data-parallel and can receive significant hardware acceleration from vector-streaming… more
Date: April 20, 2007
Creator: Liu, Y.; Jones, H.; Vaidya, S.; Perrone, M.; Tydlitat, B. & Nanda, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

An embedded boundary method for viscous, conducting compressibleflow

Description: The evolution of an Inertial Fusion Energy (IFE) chamberinvolves a repetition of short, intense depositions of energy (fromtarget ignition) into a reaction chamber, followed by the turbulentrelaxation of that energy through shock waves and thermal conduction tothe vessel walls. We present an algorithm for 2D simulations of the fluidinside an IFE chamber between fueling repetitions. Our finite-volumediscretization for the Navier-Stokes equations incorporates a Cartesiangrid treatment for irregul… more
Date: October 20, 2004
Creator: Dragojlovic, Zoran; Najmabadi, Farrokh & Day, Marcus
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Post Main Sequence Orbital Circularization of Binary Stars in the Large and Small Magellanic Clouds.

Description: We present results from a study of the orbits of eclipsing binary stars (EBs) in the Magellanic Clouds. The samples comprise 4510 EBs found in the Large Magellanic Cloud (LMC) by the MACHO project, 2474 LMC EBs found by the OGLE-II project (of which 1182 are also in the MACHO sample), 1380 in the Small Magellanic Cloud (SMC) found by the MACHO project, and 1317 SMC EBs found by the OGLE-II project (of which 677 are also in the MACHO sample); we also consider the EROS sample of 79 EBs in the bar… more
Date: November 20, 2007
Creator: Faccioli, L.; Alcock, C. & Cook, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Computational Thermochemistry and Benchmarking of Reliable Methods

Description: During the first and second years of the Computational Thermochemistry and Benchmarking of Reliable Methods project, we completed several studies using the parallel computing capabilities of the NWChem software and Molecular Science Computing Facility (MSCF), including large-scale density functional theory (DFT), second-order Moeller-Plesset (MP2) perturbation theory, and CCSD(T) calculations. During the third year, we continued to pursue the computational thermodynamic and benchmarking studies… more
Date: June 20, 2006
Creator: Feller, David F.; Dixon, David A.; Dunning, Thom H.; Dupuis, Michel; McClemore, Doug; Peterson, Kirk A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Numerical Methods for Radiation Magnetohydrodynamics in Astrophysics

Description: We describe numerical methods for solving the equations of radiation magnetohydrodynamics (MHD) for astrophysical fluid flow. Such methods are essential for the investigation of the time-dependent and multidimensional dynamics of a variety of astrophysical systems, although our particular interest is motivated by problems in star formation. Over the past few years, the authors have been members of two parallel code development efforts, and this review reflects that organization. In particular, … more
Date: November 20, 2007
Creator: Klein, R I & Stone, J M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

2005 Closure Assessments for WMA-C Tank Farms: Numerical Simulations

Description: In support of CH2M HILL Hanford Group, Inc.'s (CHG) closure of the Hanford Site Single-Shell Tank (SST) Waste Management Area (WMA) tank farms, numerical simulations of flow and solute transport were executed to investigate different potential contaminant source scenarios that may pose long-term risks to groundwater from the closure of the C Tank Farm. These simulations were based on the initial assessment effort (Zhang et al., 2003), but implemented a revised approach that examined a range of … more
Date: September 20, 2005
Creator: Freedman, Vicky L.; Zhang, Z. F.; Waichler, Scott R. & Wurstner, Signe K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Numerical simulation of low Mach number reacting flows

Description: Using examples from active research areas in combustion andastrophysics, we demonstrate a computationally efficient numericalapproach for simulating multiscale low Mach number reacting flows. Themethod enables simulations that incorporate an unprecedented range oftemporal and spatial scales, while at the same time, allows an extremelyhigh degree of reaction fidelity. Sample applications demonstrate theefficiency of the approach with respect to a traditional time-explicitintegration method, and … more
Date: June 20, 2007
Creator: Bell, John B.; Aspden, Andrew J.; Day, Marcus S. & Lijewski,Michael J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Firewall Architectures for High-Speed Networks: Final Report

Description: Firewalls are a key component for securing networks that are vital to government agencies and private industry. They enforce a security policy by inspecting and filtering traffic arriving or departing from a secure network. While performing these critical security operations, firewalls must act transparent to legitimate users, with little or no effect on the perceived network performance (QoS). Packets must be inspected and compared against increasingly complex rule sets and tables, which is a … more
Date: August 20, 2007
Creator: Fulp, Errin W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Formation of Pillars at the Boundaries between HII Regions and Molecular Clouds

Description: We investigate numerically the hydrodynamic instability of an ionization front (IF) accelerating into a molecular cloud, with imposed initial perturbations of different amplitudes. When the initial amplitude is small, the imposed perturbation is completely stabilized and does not grow. When the initial perturbation amplitude is large enough, roughly the ratio of the initial amplitude to wavelength is greater than 0.02, portions of the IF temporarily separate from the molecular cloud surface, lo… more
Date: April 20, 2006
Creator: Mizuta, A.; Kane, J. O.; Pound, M. W.; Remington, B. A.; Ryutov, D. D. & Takabe, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Numerical Simulation of a Laboratory-Scale Turbulent SlotFlame

Description: We present three-dimensional, time-dependent simulations ofthe flowfield of a laboratory-scale slot burner. The simulations areperformed using an adaptive time-dependent low Mach number combustionalgorithm based on a second-order projection formulation that conservesboth species mass and total enthalpy. The methodology incorporatesdetailed chemical kinetics and a mixture model for differential speciesdiffusion. Methane chemistry and transport are modeled using the DRM-19mechanism along with its… more
Date: April 20, 2006
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F.; Lijewski,Michael J.; Driscoll, James F. & Filatyev, Sergei A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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