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A New Approach in Advance Network Reservation and Provisioning for High-Performance Scientific Data Transfers

Description: Scientific applications already generate many terabytes and even petabytes of data from supercomputer runs and large-scale experiments. The need for transferring data chunks of ever-increasing sizes through the network shows no sign of abating. Hence, we need high-bandwidth high speed networks such as ESnet (Energy Sciences Network). Network reservation systems, i.e. ESnet's OSCARS (On-demand Secure Circuits and Advance Reservation System) establish guaranteed bandwidth of secure virtual circui… more
Date: January 28, 2010
Creator: Balman, Mehmet; Chaniotakis, Evangelos; Shoshani, Arie & Sim, Alex
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A high-order finite-volume method for hyperbolic conservation laws on locally-refined grids

Description: We present a fourth-order accurate finite-volume method for solving time-dependent hyperbolic systems of conservation laws on Cartesian grids with multiple levels of refinement. The underlying method is a generalization of that in [5] to nonlinear systems, and is based on using fourth-order accurate quadratures for computing fluxes on faces, combined with fourth-order accurate Runge?Kutta discretization in time. To interpolate boundary conditions at refinement boundaries, we interpolate in time… more
Date: January 28, 2011
Creator: McCorquodale, Peter & Colella, Phillip
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Temperature-induced martensite in magnetic shape memory Fe{sub 2}MnGa observed by photoemission electron microscopy

Description: The magnetic domain structure in single crystals of a Heusler shape memory compound near the composition Fe{sub 2}MnGa was observed during phase transition by photoelectron emission microscopy at Beamline 11.0.1.1 of the Advanced Light Source. The behavior is comparable with recent observations of an adaptive martensite phase in prototype Ni{sub 2}MnGa, although the pinning in the recent work is an epitaxial interface and in this work the e#11;ective pinning plane is a boundary between martensi… more
Date: January 18, 2012
Creator: Jenkins, Catherine; Scholl, Andreas; Kainuma, R.; Elmers, Hans-Joachim & Omori, Toshihiro
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Electronic Structure of CeFeAsO1-xFx (x=0, 0.11/x=0.12) compounds

Description: We report an extensive study on the intrinsic bulk electronic structure of the high-temperature superconductor CeFeAsO{sub 0.89}F{sub 0.11} and its parent compound CeFeAsO by soft and hard x-ray photoemission, x-ray absorption and soft-x-ray emission spectroscopies. The complementary surface/bulk probing depth, and the elemental and chemical sensitivity of these techniques allows resolving the intrinsic electronic structure of each element and correlating it with the local structure, which has … more
Date: January 25, 2011
Creator: Bondino, F.; Magnano, E.; Booth, C. H.; Offi, F.; Panaccione, G.; Malvestuto, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Electrically detected magnetic resonance in a W-band microwave cavity

Description: We describe a low-temperature sample probe for the electrical detection of magnetic resonance in a resonant W-band (94 GHz) microwave cavity. The advantages of this approach are demonstrated by experiments on silicon field-effect transistors. A comparison with conventional low-frequency measurements at X-band (9.7 GHz) on the same devices reveals an up to 100-fold enhancement of the signal intensity. In addition, resonance lines that are unresolved at X-band are clearly separated in the W-band … more
Date: January 14, 2011
Creator: Lang, V.; Lo, C. C.; George, R. E.; Lyon, S. A.; Bokor, J.; Schenkel, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

NYSERDA's Green Jobs-Green New York Program: Extending Energy Efficiency Financing To Underserved Households

Description: The New York legislature passed the Green Jobs-Green New York (GJGNY) Act in 2009. Administered by the New York State Energy Research and Development Authority (NYSERDA), GJGNY programs provide New Yorkers with access to free or low-cost energy assessments,1 energy upgrade services,2 low-cost financing, and training for various 'green-collar' careers. Launched in November 2010, GJGNY's residential initiative is notable for its use of novel underwriting criteria to expand access to energy effici… more
Date: January 24, 2011
Creator: Zimring, Mark & Fuller, Merrian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dark Shadows

Description: The U.S. Department of Energy's National Renewable Energy Laboratory, Sandia National Laboratories, the Solar Electric Power Association, the Utility Wind Integration Group, and the U.S. Department of Energy hosted a day-long public workshop on the variability of photovoltaic (PV) plants. The workshop brought together utilities, PV system developers, power system operators, and several experts to discuss the potential impacts of PV variability and uncertainty on power system operations.
Date: January 10, 2011
Creator: Mills, Andrew; Ahlstrom, Mark; Brower, Michael; Ellis, Abraham; George, Ray; Hoff, Tom et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Suppression of probe background signals via B1 field inhomogeneity

Description: A new approach combining a long pulse with the DEPTH sequence (Cory and Ritchey, Journal of Magnetic Resonance, 1988) greatly improves the efficiency for suppressing probe background signals arising from spinning modules. By applying a long initial excitation pulse in the DEPTH sequence, instead of a {pi}/2 pulse, the inhomogeneous B{sub 1} fields outside the coil can dephase the background coherence in the nutation frame. The initial long pulse and the following two consecutive EXORCYCLE {pi} … more
Date: January 27, 2011
Creator: Feng, Jian & Reimer, Jeffrey
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

DSM Electricity Savings Potential in the Buildings Sector in APP Countries

Description: The global economy has grown rapidly over the past decade with a commensurate growth in the demand for electricity services that has increased a country's vulnerability to energy supply disruptions. Increasing need of reliable and affordable electricity supply is a challenge which is before every Asia Pacific Partnership (APP) country. Collaboration between APP members has been extremely fruitful in identifying potential efficiency upgrades and implementing clean technology in the supply side o… more
Date: January 12, 2011
Creator: McNeil, MIchael; Letschert, Virginie; Shen, Bo; Sathaye, Jayant & de la Ru du Can, Stephane
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Terrestrial biogeochemical feedbacks in the climate system: from past to future

Description: The terrestrial biosphere plays a major role in the regulation of atmospheric composition, and hence climate, through multiple interlinked biogeochemical cycles (BGC). Ice-core and other palaeoenvironmental records show a fast response of vegetation cover and exchanges with the atmosphere to past climate change, although the phasing of these responses reflects spatial patterning and complex interactions between individual biospheric feedbacks. Modern observations show a similar responsiveness o… more
Date: January 5, 2010
Creator: Arneth, A.; Harrison, S. P.; Zaehle, S.; Tsigaridis, K.; Menon, S.; Bartlein, P. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Marine methane cycle simulations for the period of early global warming

Description: Geochemical environments, fates, and effects are modeled for methane released into seawater by the decomposition of climate-sensitive clathrates. A contemporary global background cycle is first constructed, within the framework of the Parallel Ocean Program. Input from organics in the upper thermocline is related to oxygen levels, and microbial consumption is parameterized from available rate measurements. Seepage into bottom layers is then superimposed, representing typical seabed fluid flow. … more
Date: January 2, 2011
Creator: Elliott, S.; Maltrud, M.; Reagan, M.T.; Moridis, G.J. & Cameron-Smith, P.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Thermal single-well injection-withdrawal tracer tests for determining fracture-matrix heat transfer area

Description: Single-well injection-withdrawal (SWIW) tracer tests involve injection of traced fluid and subsequent tracer recovery from the same well, usually with some quiescent time between the injection and withdrawal periods. SWIW are insensitive to variations in advective processes that arise from formation heterogeneities, because upon withdrawal, fluid parcels tend to retrace the paths taken during injection. However, SWIW are sensitive to diffusive processes, such as diffusive exchange of conservati… more
Date: January 15, 2010
Creator: Pruess, K. & Doughty, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Ionization of Water Clusters is Mediated by Exciton Energy Transfer from Argon Clusters

Description: The exciton energy deposited in an argon cluster, (Arn ,< n=20>) using VUV radiation is transferred to softly ionize doped water clusters, ((H2O)n, n=1-9) leading to the formation of non-fragmented clusters. Following the initial excitation, electronic energy is channeled to ionize the doped water cluster while evaporating the Ar shell, allowing identification of fragmented and complete water cluster ions. Examination of the photoionization efficiency curve shows that cluster evaporation … more
Date: January 25, 2012
Creator: Golan, Amir & Ahmed, Musahid
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Molecular orientation in soft matter thin films studied by resonant soft X-ray reflectivity

Description: We present a technique to study depth profiles of molecular orientation in soft matter thin films with nanometer resolution. The method is based on dichroism in resonant soft X-ray reflectivity using linear s- and p-polarization. It combines the chemical sensitivity of Near-Edge X-ray Absorption Fine Structure spectroscopy to specific molecular bonds and their orientation relative to the polarization of the incident beam with the precise depth profiling capability of X-ray reflectivity. We demo… more
Date: January 12, 2011
Creator: Mezger, Markus; Jerome, Blandine; Kortright, Jeffrey B.; Valvidares, Manuel; Gullikson, Eric; Giglia, Angelo et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Note on numerical study of the beam energy spread in NDCX-I

Description: The kinetic energy spread (defined here as the standard deviation of the beam particle energies) sets the ultimate theoretical limit on the longitudinal compression that can be attained on NDCX-I and NDCX-II. Experimental measurements will inevitably include the real influences on the longitudinal phase space of the beam due to injector and accelerator field imperfections1. These induced energy variations may be the real limit to the longitudinal compression in an accelerator. We report on a nu… more
Date: January 19, 2011
Creator: Vay, J. L.; Seidl, P. A. & Friedman, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hybrid Parallelism for Volume Rendering on Large, Multi- and Many-core Systems

Description: With the computing industry trending towards multi- and many-core processors, we study how a standard visualization algorithm, ray-casting volume rendering, can benefit from a hybrid parallelism approach. Hybrid parallelism provides the best of both worlds: using distributed-memory parallelism across a large numbers of nodes increases available FLOPs and memory, while exploiting shared-memory parallelism among the cores within each node ensures that each node performs its portion of the larger … more
Date: January 1, 2011
Creator: Howison, Mark; Bethel, E. Wes & Childs, Hank
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Energy and air quality implications of passive stack ventilation in residential buildings

Description: Ventilation requires energy to transport and condition the incoming air. The energy consumption for ventilation in residential buildings depends on the ventilation rate required to maintain an acceptable indoor air quality. Historically, U.S. residential buildings relied on natural infiltration to provide sufficient ventilation, but as homes get tighter, designed ventilation systems are more frequently required particularly for new energy efficient homes and retrofitted homes. ASHRAE Standard 6… more
Date: January 1, 2011
Creator: Mortensen, Dorthe Kragsig; Walker, Iain S. & Sherman, Max
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Magnetic spectroscopy and microscopy of functional materials

Description: Heusler intermetallics Mn{sub 2}Y Ga and X{sub 2}MnGa (X; Y =Fe, Co, Ni) undergo tetragonal magnetostructural transitions that can result in half metallicity, magnetic shape memory, or the magnetocaloric effect. Understanding the magnetism and magnetic behavior in functional materials is often the most direct route to being able to optimize current materials for todays applications and to design novel ones for tomorrow. Synchrotron soft x-ray magnetic spectromicroscopy techniques are well suite… more
Date: January 28, 2011
Creator: Jenkins, C.A.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Ferromagnetism in Mn-Implanted Epitaxially Grown Ge on Si(100)

Description: We have studied ferromagnetism of Mn-implanted epitaxial Ge films on silicon. The Ge films were grown by ultrahigh vacuum chemical vapor deposition using a mixture of germane (GeH{sub 4}) and methylgermane (CH{sub 3}GeH{sub 3}) gases with a carbon concentration of less than 1 at. %, and observed surface rms roughness of 0.5 nm, as measured by atomic force microscopy. Manganese ions were implanted in epitaxial Ge films grown on Si (100) wafers to an effective concentration of 16, 12, 6, and 2 at… more
Date: January 5, 2011
Creator: Guchhait, S.; Jamil, M.; Ohldag, H.; Mehta, A.; Arenholz, E.; Lian, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Statistical Behavior of Formation Process of Magnetic Vortex State in Ni80Fe20 Nanodisks

Description: Magnetic vortices in magnetic nanodots, which are characterized by an in-plane (chirality) and an out-of-plane (polarity) magnetizations, have been intensively attracted because of their high potential for technological application to data storage and memory scheme as well as their scientific interest for an understanding of fundamental physics in magnetic nanostructures. Complete understanding of the formation process of vortex state in magnetic vortex systems is very significant issue to achi… more
Date: January 14, 2011
Creator: Im, Mi-Young; Fischer, Peter; Keisuke, Yamada & Kasai, Shinya
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Validity of the thin mask approximation in extreme ultraviolet mask roughness simulations

Description: In the case of extreme ultraviolet (EUV) lithography, modeling has shown that reflector phase roughness on the lithographic mask is a significant concern due to the image plan speckle it causes and the resulting line-edge roughness on imaged features. Modeling results have recently been used to determine the requirements for future production worthy masks yielding the extremely stringent specification of 50 pm rms roughness. Owing to the scale of the problem in terms of memory requirements, pas… more
Date: January 26, 2011
Creator: Naulleau, Patrick & George, Simi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Methane Hydrate Dissociation by Depressurization in a Mount Elbert Sandstone Sample: Experimental Observations and Numerical Simulations

Description: A preserved sample of hydrate-bearing sandstone from the Mount Elbert Test Well was dissociated by depressurization while monitoring the internal temperature of the sample in two locations and the density changes at high spatial resolution using x-ray CT scanning. The sample contained two distinct regions having different porosity and grain size distributions. The hydrate dissociation occurred initially throughout the sample as a result of depressing the pressure below the stability pressure. T… more
Date: January 15, 2011
Creator: Kneafsey, T. & Moridis, G.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Automated Chemical Analysis of Internally Mixed Aerosol Particles Using X-ray Spectromicroscopy at the Carbon K-Edge

Description: We have developed an automated data analysis method for atmospheric particles using scanning transmission X-ray microscopy coupled with near edge X-ray fine structure spectroscopy (STXM/NEXAFS). This method is applied to complex internally mixed submicrometer particles containing organic and inorganic material. Several algorithms were developed to exploit NEXAFS spectral features in the energy range from 278 to 320 eV for quantitative mapping of the spatial distribution of elemental carbon, org… more
Date: January 20, 2011
Creator: Gilles, Mary K.; Moffet, R. C.; Henn, T. & Laskin, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Double-Beta Decay Half-life of {sup 136}Xe in KamLAND-Zen

Description: We present results from the KamLAND-Zen double-beta decay experiment based on an exposure of 77.6 days with 129 kg of {sup 136}Xe. The measured two-neutrino double-beta decay half-life of {sup 136}Xe is T{sup 2{nu}}{sub 1/2} = 2:38 {+-}#6; 0:02(stat)#6;{+-}0.14(syst)#2;x10{sup 21} yr, consistent with a recent measurement by EXO-200. We also obtain a lower limit for the neutrinoless double-beta decay half-life, T{sup 0{nu}}{sub 1/2} > 5.7 x#2; 10{sup 24} yr at 90% C.L.
Date: January 23, 2012
Creator: Collaboration, KamLAND-Zen; Gando, A.; Gando, Y.; Hanakago, H.; Ikeda, H.; Inoue, K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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