The National Ignition Facility and the Path to Fusion Energy (open access)

The National Ignition Facility and the Path to Fusion Energy

The National Ignition Facility (NIF) is operational and conducting experiments at the Lawrence Livermore National Laboratory (LLNL). The NIF is the world's largest and most energetic laser experimental facility with 192 beams capable of delivering 1.8 megajoules of 500-terawatt ultraviolet laser energy, over 60 times more energy than any previous laser system. The NIF can create temperatures of more than 100 million degrees and pressures more than 100 billion times Earth's atmospheric pressure. These conditions, similar to those at the center of the sun, have never been created in the laboratory and will allow scientists to probe the physics of planetary interiors, supernovae, black holes, and other phenomena. The NIF's laser beams are designed to compress fusion targets to the conditions required for thermonuclear burn, liberating more energy than is required to initiate the fusion reactions. Experiments on the NIF are focusing on demonstrating fusion ignition and burn via inertial confinement fusion (ICF). The ignition program is conducted via the National Ignition Campaign (NIC) - a partnership among LLNL, Los Alamos National Laboratory, Sandia National Laboratories, University of Rochester Laboratory for Laser Energetics, and General Atomics. The NIC program has also established collaborations with the Atomic Weapons Establishment in the …
Date: July 26, 2011
Creator: Moses, Edward
Object Type: Article
System: The UNT Digital Library
Understanding Trends in Wind Turbine Prices Over the Past Decade (open access)

Understanding Trends in Wind Turbine Prices Over the Past Decade

Taking a bottom-up approach, this report examines seven primary drivers of wind turbine prices in the United States, with the goal of estimating the degree to which each contributed to the doubling in turbine prices from 2002 through 2008, as well as the subsequent decline in prices through 2010 (our analysis does not extend into 2011 because several of these drivers are best gauged on a full-year basis due to seasonality issues). The first four of these drivers can be considered, at least to some degree, endogenous influences – i.e., those that are largely within the control of the wind industry – and include changes in: 1) Labor costs, which have historically risen during times of tight turbine supply; 2) Warranty provisions, which reflect technology performance and reliability, and are most often capitalized in turbine prices; 3) Turbine manufacturer profitability, which can impact turbine prices independently of costs; and 4) Turbine design, which for the purpose of this analysis is principally manifested through increased turbine size. The other three drivers analyzed in this study can be considered exogenous influences, in that they can impact wind turbine costs but fall mostly outside of the direct control of the wind industry. These …
Date: October 26, 2011
Creator: Bolinger, Mark & Wiser, Ryan
Object Type: Report
System: The UNT Digital Library
Towards a Microscopic Reaction Description Based on Energy Density Functionals (open access)

Towards a Microscopic Reaction Description Based on Energy Density Functionals

A microscopic calculation of reaction cross sections for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all particle-hole excitations in the target and one-nucleon pickup channels. The particle-hole states may be regarded as doorway states through which the flux flows to more complicated configurations, and subsequently to long-lived compound nucleus resonances. Target excitations for {sup 40,48}Ca, {sup 58}Ni, {sup 90}Zr and {sup 144}Sm were described in a random-phase framework using a Skyrme functional. Reaction cross sections obtained agree very well with experimental data and predictions of a state-of-the-art fitted optical potential. Couplings between inelastic states were found to be negligible, while the pickup channels contribute significantly. The effect of resonances from higher-order channels was assessed. Elastic angular distributions were also calculated within the same method, achieving good agreement with experimental data. For the first time observed absorptions are completely accounted for by explicit channel coupling, for incident energies between 10 and 70 MeV, with consistent angular distribution results.
Date: September 26, 2011
Creator: Nobre, G A; DIetrich, F S; Escher, J E; Thompson, I J; Dupuis, M; Terasaki, J et al.
Object Type: Article
System: The UNT Digital Library
High Statistics Analysis using Anisotropic Clover Lattices: (IV) Volume Dependence of Light Hadron Masses (open access)

High Statistics Analysis using Anisotropic Clover Lattices: (IV) Volume Dependence of Light Hadron Masses

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Date: April 26, 2011
Creator: Beane, S.; Chang, E.; Detmold, W.; Lin, H. W.; Luu, T.; Orginos, K. et al.
Object Type: Article
System: The UNT Digital Library
FRET Response of a Modified Ribose Receptor Expressed in the Diatom Thalassiosira pseudonana (open access)

FRET Response of a Modified Ribose Receptor Expressed in the Diatom Thalassiosira pseudonana

The ability to insert complex proteins into silica has many applications including biosensing. Previous research has demonstrated how to direct proteins to the biosilica of diatoms [1]. Here, we show that a complex fusion protein that includes an enzyme, a bacterial ribose periplasmic binding protein, flanked by fluorescent proteins constituting a FRET pair can remain functional in the frustules of living diatoms. A Sil3 tag is attached to the N-terminal end to localize the fusion protein to frustules of the diatom Thalassiosira pseudonana. When ribose was applied, a larger decrease in FRET response was seen in transformed cells than in untransformed cells. Multiple forms of the expression vector were tested to find the optimal system; specifically, a one-vector system was compared to a two-vector system and the gDNA version of the Sil3 localization tag was compared to the cDNA version. The optimal system was found to be a one-vector system with the genomic version of the Sil3 tag to direct the protein to the frustules. Localization of the enzyme to the frustules was further confirmed through cell fluorescence imaging.
Date: August 26, 2011
Creator: Miller, Hanna
Object Type: Report
System: The UNT Digital Library
Effect of Energy Efficiency Standards on Natural Gas Prices (open access)

Effect of Energy Efficiency Standards on Natural Gas Prices

A primary justification for the establishment of energy efficiency standards for home appliances is the existence of information deficiencies and externalities in the market for appliances. For example, when a long-term homeowner purchases a new gas-fired water heater, she will maximize the value of her purchase by comparing the life-cycle cost of ownership of available units, including both total installed cost - purchase price plus installation costs - and operating cost in the calculus. Choice of the appliance with the lowest life-cycle costs leads to the most economically efficient balance between capital cost and fuel cost. However, if the purchaser's expected period of ownership is shorter than the useful life of the appliance, or the purchaser does not pay for the fuel used by the appliance, as is often the case with rental property, fuel cost will be external to her costs, biasing her decision toward spending less on fuel efficiency and resulting in the purchase of an appliance with greater than optimal fuel usage. By imposing an efficiency standard on appliances, less efficient appliances are made unavailable, precluding less efficient purchases and reducing fuel usage. The reduction in fuel demanded by residential users affects the total demand for such …
Date: July 26, 2011
Creator: Carnall, Michael; Dale, Larry & Lekov, Alex
Object Type: Report
System: The UNT Digital Library
Materials Performance in USC Steam Portland (open access)

Materials Performance in USC Steam Portland

Goals of the U.S. Department of Energy's Advanced Power Systems Initiatives include power generation from coal at 60% efficiency, which requires steam conditions of up to 760 C and 340 atm, co-called advanced ultrasupercritical (A-USC) steam conditions. A limitation to achieving the goal is a lack of cost-effective metallic materials that can perform at these temperatures and pressures. Some of the more important performance limitations are high-temperature creep strength, fire-side corrosion resistance, and steam-side oxidation resistance. Nickel-base superalloys are expected to be the materials best suited for steam boiler and turbine applications above about 675 C. Specific alloys of interest include Haynes 230 and 282, Inconel 617, 625 and 740, and Nimonic 263. Further validation of a previously developed chromia evaporation model is shown by examining the reactive evaporation effects resulting from exposure of Haynes 230 and Haynes 282 to moist air environments as a function of flow rate and water content. These two alloys differ in Ti and Mn contents, which may form outer layers of TiO{sub 2} or Cr-Mn spinels. This would in theory decrease the evaporation of Cr{sub 2}O{sub 3} from the scale by decreasing the activity of chromia at the scale surface, and be somewhat self-correcting …
Date: April 26, 2011
Creator: Holcomb, G.R.; Tylczak, J. & Hu, R.
Object Type: Article
System: The UNT Digital Library
Automatic Thread-Level Parallelization in the Chombo AMR Library (open access)

Automatic Thread-Level Parallelization in the Chombo AMR Library

The increasing on-chip parallelism has some substantial implications for HPC applications. Currently, hybrid programming models (typically MPI+OpenMP) are employed for mapping software to the hardware in order to leverage the hardware?s architectural features. In this paper, we present an approach that automatically introduces thread level parallelism into Chombo, a parallel adaptive mesh refinement framework for finite difference type PDE solvers. In Chombo, core algorithms are specified in the ChomboFortran, a macro language extension to F77 that is part of the Chombo framework. This domain-specific language forms an already used target language for an automatic migration of the large number of existing algorithms into a hybrid MPI+OpenMP implementation. It also provides access to the auto-tuning methodology that enables tuning certain aspects of an algorithm to hardware characteristics. Performance measurements are presented for a few of the most relevant kernels with respect to a specific application benchmark using this technique as well as benchmark results for the entire application. The kernel benchmarks show that, using auto-tuning, up to a factor of 11 in performance was gained with 4 threads with respect to the serial reference implementation.
Date: May 26, 2011
Creator: Christen, Matthias; Keen, Noel; Ligocki, Terry; Oliker, Leonid; Shalf, John; Van Straalen, Brian et al.
Object Type: Report
System: The UNT Digital Library
Post-Closure Inspection Letter Report for Corrective Action Units on the Nevada National Security Site (open access)

Post-Closure Inspection Letter Report for Corrective Action Units on the Nevada National Security Site

This letter serves as the post-closure inspection letter report for corrective action units on the Nevada National Security Site for calendar year 2011. Copies of completed inspection checklists are included in this report.
Date: May 26, 2011
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
Volume and surface area of a spherical harmonic surface approximation to a NIF implosion core defined by HGXI/GXD images from the equator and pole (open access)

Volume and surface area of a spherical harmonic surface approximation to a NIF implosion core defined by HGXI/GXD images from the equator and pole

A solid object, such as a simplified approximation to an implosion core defined by the 17% intensity contour, can be described by a sum of spherical harmonics, following the notation of Butkov (Mathematical Physics, ISBN 0-201-00727-4, 1968; there are other notations so care is required), with Pl(x) being the usual (apparently standard) Legendre polynomial. For the present purposes, finding the volume and surface area of an implosion core defined by P0, P2, P4, M0, and M4, I will restrict the problem to consider only A{sub 00}, A{sub 20}, A{sub 40}, and A{sub 44}, with the phase angle set to eliminate the sin(m{phi}) term. Once the volume and surface area are determined, I will explore how these coefficients relate to measured quantities A0, A2/A0, A4/A0, M0, and M4/M0.
Date: October 26, 2011
Creator: Koch, J A
Object Type: Report
System: The UNT Digital Library
Annual Illness and Injury Surveillance Report: Sandia National Laboratory, 2010 (open access)

Annual Illness and Injury Surveillance Report: Sandia National Laboratory, 2010

The U.S. Department of Energy's (DOE) commitment to assuring the health and safety of its workers includes the conduct of illness and injury surveillance activities that provide an early warning system to detect health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: October 26, 2011
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
Fabrication and characterization of ultra-high resolution multilayer-coated blazed gratings (open access)

Fabrication and characterization of ultra-high resolution multilayer-coated blazed gratings

Multilayer coated blazed gratings with high groove density are the most promising candidate for ultra-high resolution soft x-ray spectroscopy. They combine the ability of blazed gratings to concentrate almost all diffraction energy in a desired high diffraction order with high reflectance soft x-ray multilayers. However in order to realize this potential, the grating fabrication process should provide a near perfect groove profile with an extremely smooth surface of the blazed facets. Here we report on successful fabrication and testing of ultra-dense saw-tooth substrates with 5,000 and 10,000 lines/mm.
Date: July 26, 2011
Creator: Voronov,, Dmitriy; Anderson, Erik; Cambie, Rossana; Dhuey, Scott; Gullikson, Eric; Salmassi, Farhad et al.
Object Type: Article
System: The UNT Digital Library
Computer Simulation of Blast Waves in a Tunnel with Sudden Decrease in Cross Section (open access)

Computer Simulation of Blast Waves in a Tunnel with Sudden Decrease in Cross Section

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Date: August 26, 2011
Creator: Glenn, L A & Neuscamman, S
Object Type: Report
System: The UNT Digital Library
Assessment of radiation effects on diagnostics and electronic devices in the National Ignition Facility (open access)

Assessment of radiation effects on diagnostics and electronic devices in the National Ignition Facility

None
Date: August 26, 2011
Creator: Khater, H; Dauffy, L; Datte, P; Eckart, M & Jackson, M
Object Type: Article
System: The UNT Digital Library
Applying graph partitioning methods in measurement-based dynamic load balancing (open access)

Applying graph partitioning methods in measurement-based dynamic load balancing

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Date: September 26, 2011
Creator: Bhatele, A; Fourestier, S; Menon, H; Kale, L V & Pellegrini, F
Object Type: Report
System: The UNT Digital Library
Fossil Fuel (CO2) Emission Verification Capability07-ERD-064Final Report (open access)

Fossil Fuel (CO2) Emission Verification Capability07-ERD-064Final Report

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Date: April 26, 2011
Creator: Guilderson, T P; Cameron-Smith, P & Lucas, D D
Object Type: Report
System: The UNT Digital Library
Avoiding hot-spots on two-level direct networks (open access)

Avoiding hot-spots on two-level direct networks

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Date: July 26, 2011
Creator: Bhatele, A; Jain, N; Gropp, W D & Kale, L V
Object Type: Article
System: The UNT Digital Library
Monitoring Spent or Reprocessed Nuclear Fuel Using Fast Neutrons (open access)

Monitoring Spent or Reprocessed Nuclear Fuel Using Fast Neutrons

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Date: May 26, 2011
Creator: Chapline, G F; Nakae, L F; Snyderman, N; Verbeke, J M & Wurtz, R
Object Type: Article
System: The UNT Digital Library
Science and Technology Review September 2011 (open access)

Science and Technology Review September 2011

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Date: July 26, 2011
Creator: Nikolic, R. J.
Object Type: Report
System: The UNT Digital Library
Simulating the Rayleigh-Taylor instability with the Ising model (open access)

Simulating the Rayleigh-Taylor instability with the Ising model

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Date: August 26, 2011
Creator: Ball, J R & Elliott, J B
Object Type: Report
System: The UNT Digital Library
Improving communication performance in dense linear algebra via topology aware collectives (open access)

Improving communication performance in dense linear algebra via topology aware collectives

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Date: July 26, 2011
Creator: Solomonik, E; Bhatele, A & Demmel, J
Object Type: Article
System: The UNT Digital Library
The formation of metastable aluminosilicates in Al - Si - H2O system: Results from solution chemistry and solid-state NMR spectroscopy/ (open access)

The formation of metastable aluminosilicates in Al - Si - H2O system: Results from solution chemistry and solid-state NMR spectroscopy/

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Date: March 26, 2011
Creator: Mason, H. E.; Maxwell, R. S. & Carroll, S. A.
Object Type: Article
System: The UNT Digital Library

Cone-Guided Fast Ignition with Imposed Magnetic Fields

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Date: August 26, 2011
Creator: Strozzi, D. J.; Tabak, M.; Larson, D. J.; Marinak, M. M.; Key, M. H.; Divol, L. et al.
Object Type: Presentation
System: The UNT Digital Library
GMTSAR: An InSAR Processing System Based on Generic Mapping Tools (open access)

GMTSAR: An InSAR Processing System Based on Generic Mapping Tools

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Date: April 26, 2011
Creator: Sandwell, D.; Mellors, R.; Tong, X.; Wei, M. & Wessel, P.
Object Type: Report
System: The UNT Digital Library