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High Performance Computing Facility Operational Assessment, FY 2011 Oak Ridge Leadership Computing Facility (open access)

High Performance Computing Facility Operational Assessment, FY 2011 Oak Ridge Leadership Computing Facility

Oak Ridge National Laboratory's Leadership Computing Facility (OLCF) continues to deliver the most powerful resources in the U.S. for open science. At 2.33 petaflops peak performance, the Cray XT Jaguar delivered more than 1.5 billion core hours in calendar year (CY) 2010 to researchers around the world for computational simulations relevant to national and energy security; advancing the frontiers of knowledge in physical sciences and areas of biological, medical, environmental, and computer sciences; and providing world-class research facilities for the nation's science enterprise. Scientific achievements by OLCF users range from collaboration with university experimentalists to produce a working supercapacitor that uses atom-thick sheets of carbon materials to finely determining the resolution requirements for simulations of coal gasifiers and their components, thus laying the foundation for development of commercial-scale gasifiers. OLCF users are pushing the boundaries with software applications sustaining more than one petaflop of performance in the quest to illuminate the fundamental nature of electronic devices. Other teams of researchers are working to resolve predictive capabilities of climate models, to refine and validate genome sequencing, and to explore the most fundamental materials in nature - quarks and gluons - and their unique properties. Details of these scientific endeavors - not …
Date: August 1, 2011
Creator: Baker, Ann E; Bland, Arthur S Buddy; Hack, James J; Barker, Ashley D; Boudwin, Kathlyn J.; Kendall, Ricky A et al.
Object Type: Report
System: The UNT Digital Library
Characterization of Optical Fiber Strength Under Applied Tensile Stress and Bending Stress (open access)

Characterization of Optical Fiber Strength Under Applied Tensile Stress and Bending Stress

Various types of tensile testing and bend radius tests were conducted on silica core/silica cladding optical fiber of different diameters with different protective buffer coatings, fabricated by different fiber manufacturers. The tensile tests were conducted to determine not only the average fiber strengths at failure, but also the distribution in fracture strengths, as well as the influence of buffer coating on fracture strength. The times-to-failure of fiber subjected to constant applied bending stresses of various magnitudes were measured to provide a database from which failure times of 20 years or more, and the corresponding minimum bend radius, could be extrapolated in a statistically meaningful way. The overall study was done to provide an understanding of optical fiber strength in tensile loading and in applied bending stress as related to applications of optical fiber in various potential coizfgurations for weapons and enhanced surveillance campaigns.
Date: August 1, 2011
Creator: Klingsporn, P.E.
Object Type: Report
System: The UNT Digital Library
Single-shot electro-optic sampling of coherent transition radiation at the A0 Photoinjector (open access)

Single-shot electro-optic sampling of coherent transition radiation at the A0 Photoinjector

Future collider applications and present high-gradient laser plasma wakefield accelerators operating with picosecond bunch durations place a higher demand on the time resolution of bunch distribution diagnostics. This demand has led to significant advancements in the field of electro-optic sampling over the past ten years. These methods allow the probing of diagnostic light such as coherent transition radiation or the bunch wakefields with sub-picosecond time resolution. Potential applications in shot-to-shot, non-interceptive diagnostics continue to be pursued for live beam monitoring of collider and pump-probe experiments. Related to our developing work with electro-optic imaging, we present results on single-shot electro-optic sampling of the coherent transition radiation from bunches generated at the A0 photoinjector.
Date: August 1, 2011
Creator: Maxwell, T. J.; Ruan, J.; Piot, P. & Thurman-Keup, R.
Object Type: Article
System: The UNT Digital Library
Transforming our Nation's Energy System, Energy Systems Integration Facility (ESIF) (open access)

Transforming our Nation's Energy System, Energy Systems Integration Facility (ESIF)

The Energy Systems Integration Facility (ESIF) on the campus of the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) will soon be the nation's first facility that can conduct integrated megawatt-scale testing of the components and strategies needed in order to safely move clean energy technologies onto the electrical grid 'in-flight' at the speed and scale required to meet national goals.
Date: August 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration: First Results Report (open access)

Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration: First Results Report

This report documents the early implementation experience for the Zero Emission Bay Area (ZEBA) Demonstration, the largest fleet of fuel cell buses in the United States. The ZEBA Demonstration group includes five participating transit agencies: AC Transit (lead transit agency), Santa Clara Valley Transportation Authority (VTA), Golden Gate Transit (GGT), San Mateo County Transit District (SamTrans), and San Francisco Municipal Railway (Muni). The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service.
Date: August 1, 2011
Creator: Chandler, K. & Eudy, L.
Object Type: Report
System: The UNT Digital Library
Review on Biomass Torrefaction Process and Product Properties and Design of Moving Bed Torrefaction System Model Development (open access)

Review on Biomass Torrefaction Process and Product Properties and Design of Moving Bed Torrefaction System Model Development

A Review on Torrefaction Process and Design of Moving Bed Torrefaction System for Biomass Processing Jaya Shankar Tumuluru1, Shahab Sokhansanj2 and Christopher T. Wright1 Idaho National Laboratory Biofuels and Renewable Energy Technologies Department Idaho Falls, Idaho 83415 Oak Ridge National Laboratory Bioenergy Resource and Engineering Systems Group Oak Ridge, TN 37831 Abstract Torrefaction is currently developing as an important preprocessing step to improve the quality of biomass in terms of physical properties, and proximate and ultimate composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of 300 C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200-230 C and 270-280 C. Thus, the process can also be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, which produces a final product that will have a lower mass but a higher …
Date: August 1, 2011
Creator: Tumuluru, Jaya Shankar; Wright, Christopher T. & Sokhansanj, Shahab
Object Type: Article
System: The UNT Digital Library
meraculous: de novo genome assembly with short paired-end reads (open access)

meraculous: de novo genome assembly with short paired-end reads

We describe a new algorithm, meraculous, for whole genome assembly of deep paired-end short reads, and apply it to the assembly of a dataset of paired 75-bp Illumina reads derived from the 15.4 megabase genome of the haploid yeast Pichia stipitis. More than 95% of the genome is recovered, with no errors; half the assembled sequence is in contigs longer than 101 kilobases and in scaffolds longer than 269 kilobases. Incorporating fosmid ends recovers entire chromosomes. Meraculous relies on an efficient and conservative traversal of the subgraph of the k-mer (deBruijn) graph of oligonucleotides with unique high quality extensions in the dataset, avoiding an explicit error correction step as used in other short-read assemblers. A novel memory-efficient hashing scheme is introduced. The resulting contigs are ordered and oriented using paired reads separated by ~280 bp or ~3.2 kbp, and many gaps between contigs can be closed using paired-end placements. Practical issues with the dataset are described, and prospects for assembling larger genomes are discussed.
Date: August 1, 2011
Creator: Chapman, Jarrod A.; Ho, Isaac; Sunkara, Sirisha; Luo, Shujun; Schroth, Gary P. & Rokhsar, Daniel S.
Object Type: Article
System: The UNT Digital Library
EPAct Requirements and Clean Cities Resources for Fleets (Fact Sheet) (Revised) (open access)

EPAct Requirements and Clean Cities Resources for Fleets (Fact Sheet) (Revised)

This fact sheet explains resources provided by the Clean Cities program to help fleet managers meet EPAct requirements.
Date: August 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Improving Vehicle Efficiency, Reducing Dependence on Foreign Oil (Fact Sheet) (open access)

Improving Vehicle Efficiency, Reducing Dependence on Foreign Oil (Fact Sheet)

This fact sheet is an overview of the Department of Energy's Vehicle Technologies program.
Date: August 1, 2011
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Equivalence in Ventilation and Indoor Air Quality (open access)

Equivalence in Ventilation and Indoor Air Quality

We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.
Date: August 1, 2011
Creator: Sherman, Max; Walker, Iain & Logue, Jennifer
Object Type: Article
System: The UNT Digital Library
Effect of pH on the Water/{alpha}-Al{sub 2}O{sub 3} (1{bar 1}02) interface structure studied by sum-frequency vibrational spectroscopy (open access)

Effect of pH on the Water/{alpha}-Al{sub 2}O{sub 3} (1{bar 1}02) interface structure studied by sum-frequency vibrational spectroscopy

Sum frequency vibrational spectroscopy (SFVS) was used to study the structure of water/{alpha}- Al{sub 2}O{sub 3} (1{bar 1}02 ) interfaces at different pH values. The OH stretch spectra are dominated by interfacial water contributions at lower frequencies, and by bonded hydroxyls on the Al{sub 2}O{sub 3} surface at higher frequencies. Protonation and deprotonation of various oxide functional groups at the {alpha}-Al{sub 2}O{sub 3} surface as pH varies can be monitored quantitatively by changes of the spectrum, allowing their pK reaction values can be estimated. The point of zero charge of the interface is found to be at pH ~ 6.7.
Date: August 1, 2011
Creator: Sung, J.; Zhang, L.; Tian, C.; Shen, Y. R. & Waychunas, G. A.
Object Type: Article
System: The UNT Digital Library
A Review of Barriers to and Opportunities for the Integration of Renewable Energy in the Southeast (open access)

A Review of Barriers to and Opportunities for the Integration of Renewable Energy in the Southeast

The objectives of this study were to prepare a summary report that examines the opportunities for and obstacles to the integration of renewable energy resources in the Southeast between now and the year 2030. The report, which is based on a review of existing literature regarding renewable resources in the Southeast, includes the following renewable energy resources: wind, solar, hydro, geothermal, biomass, and tidal. The evaluation was conducted by the Oak Ridge National Laboratory for the Energy Foundation and is a subjective review with limited detailed analysis. However, the report offers a best estimate of the magnitude, time frame, and cost of deployment of renewable resources in the Southeast based upon the literature reviewed and reasonable engineering and economic estimates. For the purposes of this report, the Southeast is defined as the states of Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia. In addition, some aspects of the report (wind and geothermal) also consider the extended Southeast, which includes Maryland, Missouri, Oklahoma, and Texas. A description of the existing base of renewable electricity installations in the region is given for each technology considered. Where available, the possible barriers and other considerations regarding …
Date: August 1, 2011
Creator: McConnell, Ben W; Hadley, Stanton W & Xu, Yan
Object Type: Report
System: The UNT Digital Library
Energy Sources and Systems Analysis: 40 South Lincoln Redevelopment District (Full Report) (open access)

Energy Sources and Systems Analysis: 40 South Lincoln Redevelopment District (Full Report)

This report presents the results of a case study to analyze district energy systems for their potential use in a project that involves redeveloping 270 units of existing public housing, along with other nearby sites. When complete, the redevelopment project will encompass more than 900 mixed-income residential units, commercial and retail properties, and open space. The analysis estimated the hourly heating, cooling, domestic hot water, and electric loads required by the community; investigated potential district system technologies to meet those needs; and researched available fuel sources to power such systems.
Date: August 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Deployment of ITS: A Summary of the 2010 National Survey Results (open access)

Deployment of ITS: A Summary of the 2010 National Survey Results

This report presents summary results of the 2010 ITS Deployment Tracking survey, the most recent survey conducted by the ITS Deployment Tracking Project. The U.S. Department of Transportation and its member agencies, including the Research and Innovative Technology Administration, have pursued a research and development agenda, the Intelligent Transportation System (ITS) Program, designed to integrate the latest in information technologies to improve the safety, mobility, and reliability of surface transportation modes. Within metropolitan areas, implementation of these advanced technologies has been accomplished by a variety of state and local transportation and emergency management agencies as well as the private sector. In order to measure the rate of ITS deployment within the nation s largest metropolitan areas, the ITS Deployment Tracking Project has conducted a nationwide survey of state and local transportation and emergency management agencies nearly every year since 1997. The results presented in this report are intended to be a summary of the entire database from the 2010 survey. Access to the complete survey results and previous national surveys are available on-line at http://www.itsdeployment.its.dot.gov. The website also provides access to survey results in the form of downloadable reports, including a survey summary for each survey type and fact sheets. …
Date: August 1, 2011
Creator: Gordon, Stephen Reed & Trombly, Jeff
Object Type: Report
System: The UNT Digital Library
Material Control and Accounting Design Considerations for High-Temperature Gas Reactors (open access)

Material Control and Accounting Design Considerations for High-Temperature Gas Reactors

The subject of this report is domestic safeguards and security by design (2SBD) for high-temperature gas reactors, focusing on material control and accountability (MC&A). The motivation for the report is to provide 2SBD support to the Next Generation Nuclear Plant (NGNP) project, which was launched by Congress in 2005. This introductory section will provide some background on the NGNP project and an overview of the 2SBD concept. The remaining chapters focus specifically on design aspects of the candidate high-temperature gas reactors (HTGRs) relevant to MC&A, Nuclear Regulatory Commission (NRC) requirements, and proposed MC&A approaches for the two major HTGR reactor types: pebble bed and prismatic. Of the prismatic type, two candidates are under consideration: (1) GA's GT-MHR (Gas Turbine-Modular Helium Reactor), and (2) the Modular High-Temperature Reactor (M-HTR), a derivative of Areva's Antares reactor. The future of the pebble-bed modular reactor (PBMR) for NGNP is uncertain, as the PBMR consortium partners (Westinghouse, PBMR [Pty] and The Shaw Group) were unable to agree on the path forward for NGNP during 2010. However, during the technology assessment of the conceptual design phase (Phase 1) of the NGNP project, AREVA provided design information and technology assessment of their pebble bed fueled plant design …
Date: August 1, 2011
Creator: Bjornard, Trond & Hockert, John
Object Type: Report
System: The UNT Digital Library
Feasibility Study of Economics and Performance of Solar Photovoltaics at the Refuse Hideaway Landfill in Middleton, Wisconsin (open access)

Feasibility Study of Economics and Performance of Solar Photovoltaics at the Refuse Hideaway Landfill in Middleton, Wisconsin

This report presents the results of an assessment of the technical and economic feasibility of deploying a photovoltaics (PV) system on a brownfield site at the Refuse Hideaway Landfill in Middleton, Wisconsin. The site currently has a PV system in place and was assessed for further PV installations. The cost, performance, and site impacts of different PV options were estimated. The economics of the potential systems were analyzed using an electric rate of $0.1333/kWh and incentives offered by the State of Wisconsin and by the serving utility, Madison Gas and Electric. According to the site production calculations, the most cost-effective system in terms of return on investment is the thin-film fixed-tilt technology. The report recommends financing options that could assist in the implementation of such a system.
Date: August 1, 2011
Creator: Salasovich, J. & Mosey, G.
Object Type: Report
System: The UNT Digital Library
In-Situ Catalysis with High Spatio-Temporal Resolution (open access)

In-Situ Catalysis with High Spatio-Temporal Resolution

None
Date: August 1, 2011
Creator: McKeown, J T; Mehraeen, S; Reed, B W; LaGrange, T B; Evans, J E; Campbell, G H et al.
Object Type: Article
System: The UNT Digital Library
Summary of FY-11 Krypton Capture Activities at the Idaho National Laboratory (open access)

Summary of FY-11 Krypton Capture Activities at the Idaho National Laboratory

This report contains a description of FY-11 Krypton capture activities utilizing physisorption techniques performed at the INL.
Date: August 1, 2011
Creator: Greenhalgh, Mitchell R.; Garn, Troy G.; Christensen, Kristi M.; Rutledge, Veronica J. & Law, Jack D.
Object Type: Report
System: The UNT Digital Library
Utilization of Renewable Oxygenates as Gasoline Blending Components (open access)

Utilization of Renewable Oxygenates as Gasoline Blending Components

This report reviews the use of higher alcohols and several cellulose-derived oxygenates as blend components in gasoline. Material compatibility issues are expected to be less severe for neat higher alcohols than for fuel-grade ethanol. Very little data exist on how blending higher alcohols or other oxygenates with gasoline affects ASTM Standard D4814 properties. Under the Clean Air Act, fuels used in the United States must be 'substantially similar' to fuels used in certification of cars for emission compliance. Waivers for the addition of higher alcohols at concentrations up to 3.7 wt% oxygen have been granted. Limited emission testing on pre-Tier 1 vehicles and research engines suggests that higher alcohols will reduce emissions of CO and organics, while NOx emissions will stay the same or increase. Most oxygenates can be used as octane improvers for standard gasoline stocks. The properties of 2-methyltetrahydrofuran, dimethylfuran, 2-methylfuran, methyl pentanoate and ethyl pentanoate suggest that they may function well as low-concentration blends with gasoline in standard vehicles and in higher concentrations in flex fuel vehicles.
Date: August 1, 2011
Creator: Yanowitz, J.; Christensen, E. & McCormick, R. L.
Object Type: Report
System: The UNT Digital Library
MESOSCALE MODELING OF DEFLAGRATION-INDUCED DECONSOLIDATION IN POLYMER-BONDED EXPLOSIVES (open access)

MESOSCALE MODELING OF DEFLAGRATION-INDUCED DECONSOLIDATION IN POLYMER-BONDED EXPLOSIVES

Initially undamaged polymer-bonded explosives can transition from conductive burning to more violent convective burning via rapid deconsolidation at higher pressures. The pressure-dependent infiltration of cracks and pores, i.e., damage, by product gases at the burn-front is a key step in the transition to convective burning. However, the relative influence of pre-existing damage and the evolution of deflagration-induced damage during the transition to convective burning is not well understood. The objective of this study is to investigate the role of microstructure and initial pressurization on deconsolidation. We performed simulations using the multi-physics hydrocode, ALE3D. HMX-Viton A served as our model explosive. A Prout-Tompkins chemical kinetic model, Vielle's Law pressure-dependent burning, Gruneisen equation-of-state, and simplified strength model were used for the HMX. The propensity for deconsolidation increased with increasing defect size and decreasing initial pressurization, as measured by the increase in burning surface area. These studies are important because they enable the development of continuum-scale damage models and the design of inherently safer explosives.
Date: August 1, 2011
Creator: Springer, H K; Glascoe, E A; Reaugh, J E; Kercher, J R & Maienschein, J L
Object Type: Article
System: The UNT Digital Library
Better Solar Cells and Manufacturing Processes Using NREL's Ultrafast Quantum Efficiency Method (Fact Sheet) (open access)

Better Solar Cells and Manufacturing Processes Using NREL's Ultrafast Quantum Efficiency Method (Fact Sheet)

Fact sheet on the FlashQE system, a 2011 R&D 100 Award winner. A solid-state optical system by NREL and Tau Science measures solar cell quantum efficiency in less than a second, enabling a suite of new capabilities for solar cell manufacturers.
Date: August 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Anomaly Detection for Resilient Control Systems Using Fuzzy-Neural Data Fusion Engine (open access)

Anomaly Detection for Resilient Control Systems Using Fuzzy-Neural Data Fusion Engine

Resilient control systems in critical infrastructures require increased cyber-security and state-awareness. One of the necessary conditions for achieving the desired high level of resiliency is timely reporting and understanding of the status and behavioral trends of the control system. This paper describes the design and development of a neural-network based data-fusion system for increased state-awareness of resilient control systems. The proposed system consists of a dedicated data-fusion engine for each component of the control system. Each data-fusion engine implements three-layered alarm system consisting of: (1) conventional threshold-based alarms, (2) anomalous behavior detector using self-organizing maps, and (3) prediction error based alarms using neural network based signal forecasting. The proposed system was integrated with a model of the Idaho National Laboratory Hytest facility, which is a testing facility for hybrid energy systems. Experimental results demonstrate that the implemented data fusion system provides timely plant performance monitoring and cyber-state reporting.
Date: August 1, 2011
Creator: Linda, Ondrej; Manic, Milos & McJunkin, Timothy R.
Object Type: Article
System: The UNT Digital Library
Overview of recent trends and developments for BPM systems (open access)

Overview of recent trends and developments for BPM systems

Beam position monitoring (BPM) systems are the workhorse of beam diagnostics for almost any kind of charged particle accelerator: linear, circular or transport-lines, operating with leptons, hadrons or heavy ions. BPMs are essential for beam commissioning, accelerator fault analysis and trouble shooting, machine optics, as well as lattice measurements, and finally, for accelerator optimization, in order to achieve the ultimate beam quality. This presentation summarizes the efforts of the beam instrumentation community on recent developments and advances on BPM technologies, i.e. BPM pickup monitors and front-end electronics (analog and digital). Principles, examples, and state-of-the-art status on various BPM techniques, serving hadron and heavy ion machines, sync light synchrotron's, as well as electron linacs for FEL or HEP applications are outlined.
Date: August 1, 2011
Creator: Wendt, M.
Object Type: Article
System: The UNT Digital Library
Building a New Energy Future with Wind Power (Fact Sheet) (open access)

Building a New Energy Future with Wind Power (Fact Sheet)

Building a New Energy Future with Wind Power (Fact Sheet), Wind and Water Power Program (WWPP)
Date: August 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library