Application of Developed APCVD Transparent Conducting Oxides and Undercoat Technologies for Economical OLED Lighting (open access)

Application of Developed APCVD Transparent Conducting Oxides and Undercoat Technologies for Economical OLED Lighting

Economics is a key factor for application of organic light emitting diodes (OLED) in general lighting relative to OLED flat panel displays that can handle high cost materials such as indium tin oxide (ITO) or Indium zinc oxide (IZO) as the transparent conducting oxide (TCO) on display glass. However, for OLED lighting to penetrate into general illumination, economics and sustainable materials are critical. The issues with ITO have been documented at the DOE SSL R&D and Manufacturing workshops for the last 5 years and the issue is being exacerbated by export controls from China (one of the major sources of elemental indium). Therefore, ITO is not sustainable because of the fluctuating costs and the United States (US) dependency on other nations such as China. Numerous alternatives to ITO/IZO are being evaluated such as Ag nanoparticles/nanowires, carbon nanotubes, graphene, and other metal oxides. Of these other metal oxides, doped zinc oxide has attracted a lot of attention over the last 10 years. The volume of zinc mined is a factor of 80,000 greater than indium and the US has significant volumes of zinc mined domestically, resulting in the ability for the US to be self-sufficient for this element that can be …
Date: January 2, 2011
Creator: Bluhm, Martin; Coffey, James; Korotkov, Roman; Polsz, Craig; Salemi, Alexandre; Smith, Robert et al.
System: The UNT Digital Library
Potential Dose Distributions at Proposed Surface Radioactivity Clearance Levels Resulting From Occupational Scenarios. (open access)

Potential Dose Distributions at Proposed Surface Radioactivity Clearance Levels Resulting From Occupational Scenarios.

The purpose of this report is to evaluate the potential dose distribution resulting from surface radioactivity, using occupational radiation exposure scenarios. The surface radioactivity clearance values considered in this analysis may ultimately replace those currently specified in the U.S. Department of Energy (DOE) requirements and guidance for radiological protection of workers, the public and the environment. The surface contamination values apply to radioactive contamination deposited on a surface (i.e., not incorporated into the interior of the material). For these calculations, the dose coefficients for intake of radionuclides were taken from ICRP Publication 68 (ICRP 1994), and external exposure dose coefficients were taken from the compact disc (CD) that accompanied Federal Guidance Report (FGR) 13 (Eckerman et al. 1999). The ICRP Publication 68 dose coefficients were based on ICRP Publication 60 (ICRP 1990) and were used specifically for worker dose calculations. The calculated dose in this analysis is the 'effective dose' (ED), rather than the 'effective dose equivalent' (EDE).
Date: August 2, 2011
Creator: Kamboj, S.; Yu, C. & Rabovsky, J.
System: The UNT Digital Library
Close out of CRADA JSA 2006S008 (open access)

Close out of CRADA JSA 2006S008

Based on the JLab study and calculations, Linde made the following changes to the LR1610 heat exchanger. The LR 1610 redesign changed two different aspects of the original LR1610 design. The heat exchanger and the boiler are wrapped differently than the original LR1610 per the following: (A) Heat Exchanger - Section A - Current LR 1610 - 2 wraps - 1 path, Redesign - 2 wraps - 2 paths; Section B: Current LR 1610 - 2 wraps - 1 path, Redesign - 2 wraps - 2 paths; (B) Boiler: Current design - 1 wrap - 2 paths, Redesign - 1 wrap - 1 path. The contents of the attachments are: (1) Assembly - Pictures of the LR1610 Redesign Heat Exchanger after manufacturing; (2) Drawings - 3D and 2D drawings used to fabricate the Redesign LR1610 Heat Exchanger and the Precooler-Boiler; (3) Performance Curves - The expected performance curves and the TS diagram for a single proposed new compressor that is more capacity than the RSX; (4) Test Pictures - Set up bench test of the LR1610 Redesign Heat Exchanger; and (5) Warm Test Data - Warm N2 test data of the LR1610 Redesign Heat Exchanger. Warm test data of the …
Date: May 2, 2011
Creator: Linde
System: The UNT Digital Library
SciDAC's Earth System Grid Center for Enabling Technologies Semiannual Progress Report October 1, 2010 through March 31, 2011 (open access)

SciDAC's Earth System Grid Center for Enabling Technologies Semiannual Progress Report October 1, 2010 through March 31, 2011

This report summarizes work carried out by the Earth System Grid Center for Enabling Technologies (ESG-CET) from October 1, 2010 through March 31, 2011. It discusses ESG-CET highlights for the reporting period, overall progress, period goals, and collaborations, and lists papers and presentations. To learn more about our project and to find previous reports, please visit the ESG-CET Web sites: http://esg-pcmdi.llnl.gov/ and/or https://wiki.ucar.edu/display/esgcet/Home. This report will be forwarded to managers in the Department of Energy (DOE) Scientific Discovery through Advanced Computing (SciDAC) program and the Office of Biological and Environmental Research (OBER), as well as national and international collaborators and stakeholders (e.g., those involved in the Coupled Model Intercomparison Project, phase 5 (CMIP5) for the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5); the Community Earth System Model (CESM); the Climate Science Computational End Station (CCES); SciDAC II: A Scalable and Extensible Earth System Model for Climate Change Science; the North American Regional Climate Change Assessment Program (NARCCAP); the Atmospheric Radiation Measurement (ARM) program; the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA)), and also to researchers working on a variety of other climate model and observation evaluation activities. The ESG-CET executive committee …
Date: April 2, 2011
Creator: Williams, D N
System: The UNT Digital Library
Massachusetts Large Blade Test Facility Final Report (open access)

Massachusetts Large Blade Test Facility Final Report

Project Objective: The Massachusetts Clean Energy Center (CEC) will design, construct, and ultimately have responsibility for the operation of the Large Wind Turbine Blade Test Facility, which is an advanced blade testing facility capable of testing wind turbine blades up to at least 90 meters in length on three test stands. Background: Wind turbine blade testing is required to meet international design standards, and is a critical factor in maintaining high levels of reliability and mitigating the technical and financial risk of deploying massproduced wind turbine models. Testing is also needed to identify specific blade design issues that may contribute to reduced wind turbine reliability and performance. Testing is also required to optimize aerodynamics, structural performance, encourage new technologies and materials development making wind even more competitive. The objective of this project is to accelerate the design and construction of a large wind blade testing facility capable of testing blades with minimum queue times at a reasonable cost. This testing facility will encourage and provide the opportunity for the U.S wind industry to conduct more rigorous testing of blades to improve wind turbine reliability.
Date: September 2, 2011
Creator: Yarala, Rahul & Priore, Rob
System: The UNT Digital Library
Customer Satisfaction Survey of Pacific Northwest National Laboratory's Technical Assistance Partners -- FY 2011 (open access)

Customer Satisfaction Survey of Pacific Northwest National Laboratory's Technical Assistance Partners -- FY 2011

The businesses that have utilized PNNL's Technology Assistance Program were sent a survey to solicit feedback about the program and to determine what, if any, outcomes resulted from the assistance provided. As part of its small business outreach, Pacific Northwest National Laboratory (PNNL) offers technology assistance to businesses with fewer than 500 employees throughout the nation and to businesses of any size in the 2 counties that contain the Hanford site. Upon request, up to 40 staff-hours of a researcher's time can be provided to address technology issues at no charge to the requesting firm. During FY 2011, PNNL completed assistance for 54 firms. Topics of the technology assistance covered a broad range, including environment, energy, industrial processes, medical, materials, computers and software, and sensors. In FY 2011, PNNL's Technology Assistance Program (TAP) was funded by PNNL Overheads. Over the past 16 years, the Technology Assistance Program has received total funding of nearly $2.8 million from several federal and private sources.
Date: November 2, 2011
Creator: Conger, Robin L. & Spanner, Gary E.
System: The UNT Digital Library
Synthesis of trevorite to capture Tc (open access)

Synthesis of trevorite to capture Tc

Spinel containing technetium can be used to prevent Tc volatilization during vitrification of radioactive waste. Spinel dissolves in glass at elevated temperatures. This study focuses on the synthesis of spinel and the retention of rhenium, a nonradioactive surrogate for Tc in the crystals. To produce trevorite, a nickel-iron spinel (NiFe2O4), Fe and Ni nitrates were mixed with alkali nitrates along with Al(OH)3 and heated to 500 to 800°C. The trevorite content in samples (up to 40 mass%) was measured with x-ray diffraction. Viable samples were rerun with KReO4. Scanning electron microscopy-energy dispersive spectroscopy detected that Re became partly immobilized in spinel-forming crystals.
Date: September 2, 2011
Creator: Tsui, Colin
System: The UNT Digital Library
Business Case for Energy Efficiency in Support of Climate Change Mitigation, Economic and Societal Benefits in India (open access)

Business Case for Energy Efficiency in Support of Climate Change Mitigation, Economic and Societal Benefits in India

This study seeks to provide policymakers and other stakeholders with actionable information towards a road map for reducing energy consumption cost-effectively. We focus on individual end use equipment types (hereafter referred to as appliance groups) that might be the subject of policies - such as labels, energy performance standards, and incentives - to affect market transformation in the short term, and on high-efficiency technology options that are available today. the high efficiency or Business Case scenario is constructed around a model of cost-effective efficiency improvement. Our analysis demonstrates that a significant reduction in energy consumption and emissions is achievable at net negative cost, that is, as a profitable investment for consumers. Net savings are calculated assuming no additional costs to energy consumption such as carbon taxes. Savings relative to the base case as calculated in this way is often referred to as “economic savings potential”. So far, the Indian market has responded favorably to government efficiency initiatives, with Indian manufacturers producing a higher fraction of high-efficiency equipment than before program implementation. This study highlights both the financial benefit and the scope of potential impact for adopting this equipment, all of which is already readily available on the market. The approach …
Date: December 2, 2011
Creator: McNeil, Michael A.; Ke, Jing; Can, Stephane de la Rue du; Letschert, Virginie E. & McMahon, James E.
System: The UNT Digital Library
Enhancing the CDF's B physics program with a faster data acquisition system. (open access)

Enhancing the CDF's B physics program with a faster data acquisition system.

The physics program of Run II at the Tevatron includes precision electroweak measurements such as the determination of the top quark and W boson masses; bottom and charm physics including the determination of the B{sub s} and D{sup 0} mixing parameters; studies of the strong interaction; and searches for the Higgs particle, supersymmetric particles, hidden space-time dimensions and quark substructure. All of these measurements benefit from a high-resolution tracking detector. Most of them rely heavily on the efficient identification of heavy flavored B hadrons by detection of displaced secondary vertices, and are enhanced by the capability to trigger on tracks not coming from the primary vertex. This is uniquely provided by CDF's finely-segmented silicon detectors surrounding the interaction region. Thus CDF experiment's physics potential critically depends on the performance of its silicon detectors. The CDF silicon detectors were designed to operate up to 2-3 fb{sup -1} of accumulated pji collisions, with an upgrade planned thereafter. However, the upgrade project was canceled in 2003 and Run II has been extended through 2011, with an expected total delivered integrated luminosity of 12 fb{sup -1} or more. Several preventive measures were taken to keep the original detector operational and maintain its performance. The …
Date: March 2, 2011
Creator: Maksimovic, Dr. Petar
System: The UNT Digital Library
Modification of Particle Distributions by MHD Instabilities II (open access)

Modification of Particle Distributions by MHD Instabilities II

The modification of particle distributions by low amplitude magnetohydrodynamic modes is an important topic for magnetically confined plasmas. Low amplitude modes are known to be capable of producing significant modification of injected neutral beam profiles, and the same can be expected in burning plasmas for the alpha particle distributions. Flattening of a distribution in an island due to phase mixing and portions of phase space becoming stochastic lead to modification of the particle distribution, a process extremely rapid in the time scale of an experiment but still very long compared to the time scale of guiding center simulations. Large amplitude modes can cause profile avalanche and particle loss. Thus it is very valuable to be able to predict the temporal evolution of a particle distribution produced by a given spectrum of magnetohydrodynamic modes. In this paper we further develop and investigate the use of a new method of determining domains of phase space in which good KAM surfaces do not exist and use this method to examine a well documented case of profile modification by instabilities.
Date: March 2, 2011
Creator: White, Roscoe B.
System: The UNT Digital Library
Proceedings of RIKEN BNL Research Center Workshop: Brookhaven Summer Program on Nucleon Spin Physics (open access)

Proceedings of RIKEN BNL Research Center Workshop: Brookhaven Summer Program on Nucleon Spin Physics

Understanding the structure of the nucleon is of fundamental importance in sub-atomic physics. Already the experimental studies on the electro-magnetic form factors in the 1950s showed that the nucleon has a nontrivial internal structure, and the deep inelastic scattering experiments in the 1970s revealed the partonic substructure of the nucleon. Modern research focuses in particular on the spin and the gluonic structure of the nucleon. Experiments using deep inelastic scattering or polarized p-p collisions are carried out in the US at the CEBAF and RHIC facilities, respectively, and there are other experimental facilities around the world. More than twenty years ago, the European Muon Collaboration published their first experimental results on the proton spin structure as revealed in polarized deep inelastic lepton-nucleon scattering, and concluded that quarks contribute very little to the proton's spin. With additional experimental and theoretical investigations and progress in the following years, it is now established that, contrary to naive quark model expectations, quarks and anti-quarks carry only about 30% of the total spin of the proton. Twenty years later, the discovery from the polarized hadron collider at RHIC was equally surprising. For the phase space probed by existing RHIC experiments, gluons do not seem to …
Date: August 2, 2011
Creator: Aschenauer, A.; Qiu, Jianwei; Vogelsang, W. & Yuan, F.
System: The UNT Digital Library
CHARACTERISTICS OF RANGE HOODS IN CALIFORNIA HOMES DATA COLLECTED FROM A REAL ESTATE WEB SITE (open access)

CHARACTERISTICS OF RANGE HOODS IN CALIFORNIA HOMES DATA COLLECTED FROM A REAL ESTATE WEB SITE

Venting range hoods are important residential ventilation components that remove pollutants generated by cooking activities and natural gas cooking burners. To address the lack of data on range hood installations in California, we conducted a survey by examining photographs of homes for sale or rent listed on a popular real estate web site. The survey was conducted in November 2010 and April–May 2011. Posted photos of the homes were reviewed to determine if a hood was installed, the type of hood, and two installation details that can impact performance, namely the height above the cooktop and the degree to which the hood covers the cooktop burners. We additionally collected information about the homes, including asking price for purchase or rent, type of building (e.g. detached house, townhouse or apartment), building age, floor area, and cooktop fuel type. Listings were first sampled to focus on homes built since 2005, then randomly sampled to include varied prices and locations around the state. Data were obtained for 1002 homes built between 1865 and 2011 (median year built 1989). Homes for sale varied in asking price from $16,000 to $16,500,000 (median $353,000) and homes for rent varied from $500 to $25,000 (median $2125) per …
Date: September 2, 2011
Creator: Klug, Victoria; Singer, Brett; Bedrosian, Tod & DCruz, Chris
System: The UNT Digital Library
Cultural Resources Review for Closure of the nonradioactive Dangerous Waste Landfill and Solid Waste Landfill in the 600 Area, Hanford Site, Benton County, Washington, HCRC# 2010-600-018R (open access)

Cultural Resources Review for Closure of the nonradioactive Dangerous Waste Landfill and Solid Waste Landfill in the 600 Area, Hanford Site, Benton County, Washington, HCRC# 2010-600-018R

The U.S. Department of Energy Richland Operations Office is proposing to close the Nonradioactive Dangerous Waste Landfill (NRDWL) and Solid Waste Landfill (SWL) located in the 600 Area of the Hanford Site. The closure of the NRDWL/SWL entails the construction of an evapotranspiration cover over the landfill. This cover would consist of a 3-foot (1-meter) engineered layer of fine-grained soil, modified with 15 percent by weight pea gravel to form an erosion-resistant topsoil that will sustain native vegetation. The area targeted for silt-loam borrow soil sits in Area C, located in the northern central portion of the Fitzner/Eberhardt Arid Lands Ecology (ALE) Reserve Unit. The pea gravel used for the mixture will be obtained from both off-site commercial sources and an active gravel pit (Pit #6) located just west of the 300 Area of the Hanford Site. Materials for the cover will be transported along Army Loop Road, which runs from Beloit Avenue (near the Rattlesnake Barricade) east-northeast to the NRDWL/SWL, ending at State Route 4. Upgrades to Army Loop Road are necessary to facilitate safe bidirectional hauling traffic. This report documents a cultural resources review of the proposed activity, conducted according to Section 106 of the National Historic Preservation …
Date: February 2, 2011
Creator: Gutzeit, Jennifer L.; Kennedy, Ellen P.; Bjornstad, Bruce N.; Sackschewsky, Michael R.; Sharpe, James J.; DeMaris, Ranae et al.
System: The UNT Digital Library
Proceedings of RIKEN BNL Research Center Workshop: Initial State Fluctuations and Final-State Particle Correlations (open access)

Proceedings of RIKEN BNL Research Center Workshop: Initial State Fluctuations and Final-State Particle Correlations

N/A
Date: February 2, 2011
Creator: A., Dumitru; Molnar, D. & Wang, F.
System: The UNT Digital Library
Comparison and Validation of HEU and LEU Modeling Results to HEU Experimental Benchmark Data for the Massachusetts Institute of Technology MITR Reactor. (open access)

Comparison and Validation of HEU and LEU Modeling Results to HEU Experimental Benchmark Data for the Massachusetts Institute of Technology MITR Reactor.

The Massachusetts Institute of Technology Reactor (MITR-II) is a research reactor in Cambridge, Massachusetts designed primarily for experiments using neutron beam and in-core irradiation facilities. It delivers a neutron flux comparable to current LWR power reactors in a compact 6 MW core using Highly Enriched Uranium (HEU) fuel. In the framework of its non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context, most research and test reactors both domestic and international have started a program of conversion to the use of Low Enriched Uranium (LEU) fuel. A new type of LEU fuel based on an alloy of uranium and molybdenum (UMo) is expected to allow the conversion of U.S. domestic high performance reactors like the MITR-II reactor. Towards this goal, comparisons of MCNP5 Monte Carlo neutronic modeling results for HEU and LEU cores have been performed. Validation of the model has been based upon comparison to HEU experimental benchmark data for the MITR-II. The objective of this work was to demonstrate a model which could represent the experimental HEU data, and therefore could provide a basis to demonstrate LEU core performance. This report …
Date: March 2, 2011
Creator: Newton, T. H.; Wilson, E. H; Bergeron, A.; Horelik, N.; Stevens, J. (Nuclear Engineering Division) & Lab.), (MIT Nuclear Reactor
System: The UNT Digital Library
DOSE ASSESSMENT OF THE FINAL INVENTORIES IN CENTER SLIT TRENCHES ONE THROUGH FIVE (open access)

DOSE ASSESSMENT OF THE FINAL INVENTORIES IN CENTER SLIT TRENCHES ONE THROUGH FIVE

In response to a request from Solid Waste Management (SWM), this study evaluates the performance of waste disposed in Slit Trenches 1-5 by calculating exposure doses and concentrations. As of 8/19/2010, Slit Trenches 1-5 have been filled and are closed to future waste disposal in support of an ARRA-funded interim operational cover project. Slit Trenches 6 and 7 are currently in operation and are not addressed within this analysis. Their current inventory limits are based on the 2008 SA and are not being impacted by this study. This analysis considers the location and the timing of waste disposal in Slit Trenches 1-5 throughout their operational life. In addition, the following improvements to the modeling approach have been incorporated into this analysis: (1) Final waste inventories from WITS are used for the base case analysis where variance in the reported final disposal inventories is addressed through a sensitivity analysis; (2) Updated K{sub d} values are used; (3) Area percentages of non-crushable containers are used in the analysis to determine expected infiltration flows for cases that consider collapse of these containers; (4) An updated representation of ETF carbon column vessels disposed in SLIT3-Unit F is used. Preliminary analyses indicated a problem meeting …
Date: May 2, 2011
Creator: Collard, L.; Hamm, L. & Smith, F.
System: The UNT Digital Library
Neutronic Analyses for HEU to LEU fuel conversion of the Massachusetts Institute of Technology. (open access)

Neutronic Analyses for HEU to LEU fuel conversion of the Massachusetts Institute of Technology.

The Massachusetts Institute of Technology (MIT) reactor (MITR-II), based in Cambridge, Massachusetts, is a research reactor designed primarily for experiments using neutron beam and in-core irradiation facilities. It delivers a neutron flux comparable to current LWR power reactors in a compact 6 MW core using Highly Enriched Uranium (HEU) fuel. In the framework of its non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context, most research and test reactors both domestic and international have started a program of conversion to the use of Low Enriched Uranium (LEU) fuel. A new type of LEU fuel based on a mixture of uranium and molybdenum (UMo) is expected to allow the conversion of compact high performance reactors like the MITR-II. This report presents the results of steady state neutronic safety analyses for conversion of MITR-II from the use of HEU fuel to the use of U-Mo LEU fuel. The objective of this work was to demonstrate that the safety analyses meet current requirements for an LEU core replacement of MITR-II.
Date: March 2, 2011
Creator: Wilson, E. H.; Newton, T. H.; Bergeron, A.; Horelik, N.; Stevens, J. G (Nuclear Engineering Division) & NS), (
System: The UNT Digital Library
PILOT-SCALE TESTING OF THE SUSPENSION OF MST, CST, AND SIMULATED SLUDGE SLURRIES IN A SLUDGE TANK (open access)

PILOT-SCALE TESTING OF THE SUSPENSION OF MST, CST, AND SIMULATED SLUDGE SLURRIES IN A SLUDGE TANK

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Following strontium, actinide, and cesium removal, the concentrated solids will be transported to a sludge tank (i.e., monosodium titanate (MST)/sludge solids to Tank 42H or Tank 51H and crystalline silicotitanate (CST) to Tank 40H) for eventual transfer to the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for mixing MST, CST, and simulated sludge. The purpose of this pilot scale testing is to determine the pump requirements for mixing MST and CST with sludge in a sludge tank and to determine whether segregation of particles occurs during settling. Tank 40H and Tank 51H have four Quad Volute pumps; Tank 42H has four standard pumps. The pilot-scale tank is a 1/10.85 linear scaled model of Tank 40H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 40H. The pump locations correspond to the current locations in Tank 40H (Risers B2, …
Date: August 2, 2011
Creator: Poirier, M.; Qureshi, Z.; Restivo, M.; Steeper, T.; Williams, M. & Herman, D.
System: The UNT Digital Library
LLNL Input to SNL L2 MS: Report on the Basis for Selection of Disposal Options (open access)

LLNL Input to SNL L2 MS: Report on the Basis for Selection of Disposal Options

This mid-year deliverable has two parts. The first part is a synopsis of J. Blink's interview of the former Nevada Attorney General, Frankie Sue Del Papa, which was done in preparation for the May 18-19, 2010 Legal and Regulatory Framework Workshop held in Albuquerque. The second part is a series of sections written as input for the SNL L2 Milestone M21UF033701, due March 31, 2011. Disposal of high-level radioactive waste is categorized in this review into several categories. Section II discusses alternatives to geologic disposal: space, ice-sheets, and an engineered mountain or mausoleum. Section III discusses alternative locations for mined geologic disposal: islands, coastlines, mid-continent, and saturated versus unsaturated zone. Section IV discusses geologic disposal alternatives other than emplacement in a mine: well injection, rock melt, sub-seabed, and deep boreholes in igneous or metamorphic basement rock. Finally, Secton V discusses alternative media for mined geologic disposal: basalt, tuff, granite and other igneous/metamorphic rock, alluvium, sandstone, carbonates and chalk, shale and clay, and salt.
Date: March 2, 2011
Creator: Sutton, M.; Blink, J. A. & Halsey, W. G.
System: The UNT Digital Library
ANSTO Samples - 1-week Report (open access)

ANSTO Samples - 1-week Report

None
Date: February 2, 2011
Creator: Kristo, M. J.; Hutcheon, I. D.; Moody, K. J.; Grant, P. M.; Conrado, C. L.; Wooddy, P. T. et al.
System: The UNT Digital Library
Situated Usability Testing for Security Systems (open access)

Situated Usability Testing for Security Systems

While usability testing is well established, assessing the usability of security software, tools, or methods deserves more careful consideration. It has been argued that dealing with security has become too difficult for individuals or organizations to manage effectively or to use conveniently. As difficult as it is for system administrators and developers to deal with, security is even more challenging for casual users. Indeed, it is much too easy for casual/home users to configure the security of their systems in non-optimal ways that leave their systems inadvertently insecure. This is exacerbated by the fact that casual users are focused on matters other than security, and likely would prefer not even to think about security. This brief report argues that when security and/or privacy are part of the equation, traditional methods for usability testing should be re-considered. The purpose of this brief report is to argue for and outline a method associated with a new approach to usability testing for examining usable security issues.
Date: March 2, 2011
Creator: Greitzer, Frank L.
System: The UNT Digital Library
CESR Conversion Damping Ring Studies of Electron Cloud Instabilities (CESR-TA) (open access)

CESR Conversion Damping Ring Studies of Electron Cloud Instabilities (CESR-TA)

In the International Linear Collider, two linear accelerators will accelerate bunches of positrons and electrons to over a hundred billion electron volts and collide them in a central detector. In order to obtain useful collision rates, the bunches, each containing twenty billion particles, must be compressed to a cross section of a few nanometers by a few hundred nanometers. In order to prepare these ultra high density bunches, damping rings (DRs) are employed before the linear accelerators. The DRs take the high emittance bunches that are provided by the electron and positron sources and, through the process of radiation damping, squeeze them into ultra low emittance beams that are ready for the main linear accelerators. In the damping rings, a number of effects can prevent the successful preparation of the beams. In the electron ring, an effect known as the fast ion instability can lead to beam growth and, in the positron ring, the build-up of an electron cloud (EC), which interacts with the circulating bunches, can produce the same effect. EC build-up and the subsequent interaction of the cloud with the positron beam in the DR have been identified as major risks for the successful construction of a linear …
Date: August 2, 2011
Creator: Rubin, David L. & Palmer, Mark A.
System: The UNT Digital Library
Quantum Monte Carlo Endstation for Petascale Computing (open access)

Quantum Monte Carlo Endstation for Petascale Computing

The major achievements enabled by QMC Endstation grant include * Performance improvement on clusters of x86 multi-core systems, especially on Cray XT systems * New and improved methods for the wavefunction optimizations * New forms of trial wavefunctions * Implementation of the full application on NVIDIA GPUs using CUDA The scaling studies of QMCPACK on large-scale systems show excellent parallel efficiency up to 216K cores on Jaguarpf (Cray XT5). The GPU implementation shows speedups of 10-15x over the CPU implementation on older generation of x86. We have implemented hybrid OpenMP/MPI scheme in QMC to take advantage of multi-core shared memory processors of petascale systems. Our hybrid scheme has several advantages over the standard MPI-only scheme. * Memory optimized: large read-only data to store one-body orbitals and other shared properties to represent the trial wave function and many-body Hamiltonian can be shared among threads, which reduces the memory footprint of a large-scale problem. * Cache optimized: the data associated with an active Walker are in cache during the compute-intensive drift-diffusion process and the operations on an Walker are optimized for cache reuse. Thread-local objects are used to ensure the data affinity to a thread. * Load balanced: Walkers in an ensemble …
Date: March 2, 2011
Creator: Ceperley, David
System: The UNT Digital Library
Pyramid Resource Center-Green Energy Center (open access)

Pyramid Resource Center-Green Energy Center

There are currently over 3,500 USA/Canadian landfills listed by the EPA/EC and like numbers in Europe that are producing methane-rich landfill gas (LFG). This gas is typically made up of 50-percent methane (CH4), 35-percent carbon dioxide (CO2), and 2 to 25% nitrogen and oxygen (N2 & O2), plus dozens of dilute contaminants. LFG is classified as a renewable fuel, because it is generated via biological decay of municipal solid waste, a constant byproduct of human activity. To date, most LFG has been allowed to escape into the atmosphere. On account of its high CH4 content, LFG may contribute to climate change, as CH4 is one of the most harmful greenhouse gases with 21 times the global warming potential of CO2. Of the landfills that collect LFG, most simply flare it. In the past decade, some landfills have begun to use LFG for electricity generation or for direct combustion as low Btu gas. Very few landfills upgrade LFG to high Btu gas. A patented CO2 WashTM process developed by Acrion Technologies Inc., and licensed to Firm Green Inc. shows promise as an economically and environmentally sustainable process to recover energy and prevent pollution from landfills. The CO2 WashTM has already been …
Date: September 2, 2011
Creator: Flory, Paul, D.
System: The UNT Digital Library