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Depot Maintenance: DOD's Report to Congress on Its Public-Private Partnerships at Its Centers of Industrial and Technical Excellence (CITEs) Is Not Complete and Additional Information Would Be Useful (open access)

Depot Maintenance: DOD's Report to Congress on Its Public-Private Partnerships at Its Centers of Industrial and Technical Excellence (CITEs) Is Not Complete and Additional Information Would Be Useful

Correspondence issued by the Government Accountability Office with an abstract that begins "For several years, the Department of Defense (DOD) and Congress have encouraged the defense logistics support community to pursue partnerships with the private sector to combine the best commercial processes and practices with DOD's extensive maintenance capabilities. These public-private partnerships can combine the resources, risks, and rewards of public agencies and private companies and are intended to provide greater efficiency, better access to capital, and improved compliance with a range of government regulations. Although DOD has collected information on depot-level partnering arrangements for several years, DOD first issued a policy encouraging the use of public-private depot maintenance partnerships to improve the efficiency and viability of its depots in January 2002. DOD expects these improvements to depot operations to ultimately improve support for the warfighter. Public-private partnerships for depot-level maintenance are cooperative arrangements between a depot-level maintenance activity and one or more private sector entities to perform DOD or defense-related work, to utilize DOD depot facilities and equipment, or both. Pursuant to Section 2474 of Title 10, United States Code, the secretaries of the military departments (and the Secretary of Defense in the case of defense agencies) designated their …
Date: July 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Searches for Large Extra Dimensions at the Tevatron (open access)

Searches for Large Extra Dimensions at the Tevatron

None
Date: July 1, 2008
Creator: Krutelyov, Vyacheslav
Object Type: Article
System: The UNT Digital Library
Linearly Scaling 3D Fragment Method for Large-Scale Electronic Structure Calculations (open access)

Linearly Scaling 3D Fragment Method for Large-Scale Electronic Structure Calculations

We present a new linearly scaling three-dimensional fragment (LS3DF) method for large scale ab initio electronic structure calculations. LS3DF is based on a divide-and-conquer approach, which incorporates a novel patching scheme that effectively cancels out the artificial boundary effects due to the subdivision of the system. As a consequence, the LS3DF program yields essentially the same results as direct density functional theory (DFT) calculations. The fragments of the LS3DF algorithm can be calculated separately with different groups of processors. This leads to almost perfect parallelization on tens of thousands of processors. After code optimization, we were able to achieve 35.1 Tflop/s, which is 39percent of the theoretical speed on 17,280 Cray XT4 processor cores. Our 13,824-atom ZnTeO alloy calculation runs 400 times faster than a direct DFTcalculation, even presuming that the direct DFT calculation can scale well up to 17,280 processor cores. These results demonstrate the applicability of the LS3DF method to material simulations, the advantage of using linearly scaling algorithms over conventional O(N3) methods, and the potential for petascale computation using the LS3DF method.
Date: July 1, 2008
Creator: Wang, Lin-Wang; Lee, Byounghak; Shan, Hongzhang; Zhao, Zhengji; Meza, Juan; Strohmaier, Erich et al.
Object Type: Article
System: The UNT Digital Library
The Reactivity and Structural Dynamics of Supported Metal Nanoclusters Using Electron Microscopy, in situ X-Ray Spectroscopy, Electronic Structure Theories, and Molecular Dynamics Simulations. (open access)

The Reactivity and Structural Dynamics of Supported Metal Nanoclusters Using Electron Microscopy, in situ X-Ray Spectroscopy, Electronic Structure Theories, and Molecular Dynamics Simulations.

The distinguishing feature of our collaborative program of study is the focus it brings to emergent phenomena originating from the unique structural/electronic environments found in nanoscale materials. We exploit and develop frontier methods of atomic-scale materials characterization based on electron microscopy (Yang) and synchrotron X-ray absorption spectroscopy (Frenkel) that are in turn coupled innately with advanced first principles theory and methods of computational modeling (Johnson). In the past year we have made significant experimental advances that have led to important new understandings of the structural dynamics of what are unquestionably the most important classes of heterogeneous catalysts—the materials used to both produce and mitigate the consequences of the use of liquid hydrocarbon fuels.
Date: July 1, 2008
Creator: Yang, Judith C. & Ralph G. Nuzzo, Duane Johnson, Anatoly Frenkel
Object Type: Report
System: The UNT Digital Library
Recapitalizing EMSL: Meeting Future Science and Technology Challenges (open access)

Recapitalizing EMSL: Meeting Future Science and Technology Challenges

EMSL, located in Richland, Washington, is a national scientific user facility operated for the U.S. Department of Energy (DOE) by the Pacific Northwest National Laboratory. The vision that directed the development of EMSL as a problem-solving environment for environmental molecular science has led to significant scientific progress in many areas ranging from subsurface science to atmospheric sciences, and from biochemistry to catalysis. Our scientific staff and users are recognized nationally and internationally for their significant contributions to solving challenging scientific problems. We have explored new scientific frontiers and organized a vibrant and diverse user community in support of our mission as a national scientific user facility that provides integrated experimental and computational resources in the environmental molecular sciences. Users from around the world - from academia to industry and national laboratories to international research organizations - use the resources of EMSL because of the quality of science that we enable.
Date: July 1, 2008
Creator: Felmy, Andrew R.
Object Type: Report
System: The UNT Digital Library
Metal oxide coating of carbon supports for supercapacitor applications. (open access)

Metal oxide coating of carbon supports for supercapacitor applications.

The global market for wireless sensor networks in 2010 will be valued close to $10 B, or 200 M units. TPL, Inc. is a small Albuquerque based business that has positioned itself to be a leader in providing uninterruptible power supplies in this growing market with projected revenues expected to exceed $26 M in 5 years. This project focused on improving TPL, Inc.'s patent-pending EnerPak{trademark} device which converts small amounts of energy from the environment (e.g., vibrations, light or temperature differences) into electrical energy that can be used to charge small energy storage devices. A critical component of the EnerPak{trademark} is the supercapacitor that handles high power delivery for wireless communications; however, optimization and miniaturization of this critical component is required. This proposal aimed to produce prototype microsupercapacitors through the integration of novel materials and fabrication processes developed at New Mexico Technology Research Collaborative (NMTRC) member institutions. In particular, we focused on developing novel ruthenium oxide nanomaterials and placed them into carbon supports to significantly increase the energy density of the supercapacitor. These improvements were expected to reduce maintenance costs and expand the utility of the TPL, Inc.'s device, enabling New Mexico to become the leader in the growing global …
Date: July 1, 2008
Creator: Boyle, Timothy J.; Tribby, Louis, J.; Lakeman, Charles D. E.; Han, Sang M.; Lambert, Timothy N. & Fleig, Patrick F.
Object Type: Report
System: The UNT Digital Library
Steam System Efficiency Optimized After J.R. Simplot Fertilizer Plant Receives Energy Assessment (open access)

Steam System Efficiency Optimized After J.R. Simplot Fertilizer Plant Receives Energy Assessment

This case study describes how the J.R. Simplot company's Don Plant in Pocatello, Idaho, achieved annual savings of $335,000 and 75,000 MMBtu, with a simple payback of 6.5 months, after receiving a DOE Save Energy Now energy assessment.
Date: July 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Impedance Noise Identification for State-of-Health Prognostics (open access)

Impedance Noise Identification for State-of-Health Prognostics

Impedance Noise Identification is an in-situ method of measuring battery impedance as a function of frequency using a random small signal noise excitation source. Through a series of auto- and cross-correlations and Fast Fourier Transforms, the battery complex impedance as a function of frequency can be determined. The results are similar to those measured under a lab-scale electrochemical impedance spectroscopy measurement. The lab-scale measurements have been shown to correlate well with resistance and power data that are typically used to ascertain the remaining life of a battery. To this end, the Impedance Noise Identification system is designed to acquire the same type of data as an on-board tool. A prototype system is now under development, and results are being compared to standardized measurement techniques such as electrochemical impedance spectroscopy. A brief description of the Impedance Noise Identification hardware system and representative test results are presented.
Date: July 1, 2008
Creator: Christophersen, Jon P.; Motloch, Chester G.; Morrison, John L.; Donnellan, Ian B. & Morrison, William H.
Object Type: Article
System: The UNT Digital Library
Analytic Framework for Evaluation of State Energy Efficiency and Renewable Energy Policies with Reference to Stakeholder Drivers (open access)

Analytic Framework for Evaluation of State Energy Efficiency and Renewable Energy Policies with Reference to Stakeholder Drivers

This report presents the framework that was developed to analyze energy efficiency and renewable energy policies on the state level based on how well they meet the stakeholder drivers.
Date: July 1, 2008
Creator: Brown, E. & Mosey, G.
Object Type: Report
System: The UNT Digital Library
Summary on the Fundamental Mode Damper Experiments of the 56 MHz SRF Cavity (open access)

Summary on the Fundamental Mode Damper Experiments of the 56 MHz SRF Cavity

This report summarizes the experimental results done with the fundamental damper for the 56 MHz prototype Cu cavity. Various measurements were done on the cavity including determination of the position of the fundamental damper and measurement of the frequency and Q factor changes while the damper is withdrawn. Prediction on the dissipated power while the damper is withdrawn was made by experiments.
Date: July 1, 2008
Creator: Choi,E. & Hahn, H.
Object Type: Report
System: The UNT Digital Library
Using Visual Analytics to Maintain Situation Awareness in Astrophysics (open access)

Using Visual Analytics to Maintain Situation Awareness in Astrophysics

We present a novel collaborative visual analytics application for cognitively overloaded users in the astrophysics domain. The system was developed for scientists needing to analyze heterogeneous, complex data under time pressure, and then make predictions and time-critical decisions rapidly and correctly under a constant influx of changing data. The Sunfall Data Taking system utilizes severalnovel visualization and analysis techniques to enable a team of geographically distributed domain specialists to effectively and remotely maneuver a custom-built instrument under challenging operational conditions. Sunfall Data Taking has been in use for over eighteen months by a major international astrophysics collaboration (the largest data volume supernova search currently in operation), and has substantially improved the operational efficiency of its users. We describe the system design process by an interdisciplinary team, the system architecture, and the results of an informal usability evaluation of the production system by domain experts in the context of Endsley?s three levels of situation awareness.
Date: July 1, 2008
Creator: Aragon, Cecilia R.; Poon, Sarah S.; Aldering, Gregory S.; Thomas, Rollin C. & Quimby, Robert
Object Type: Article
System: The UNT Digital Library
Clean Cities Now, Vol. 12, No. 3 - July 2008 (open access)

Clean Cities Now, Vol. 12, No. 3 - July 2008

Clean Cities Now is the official newsletter of DOE's Clean Cities program. It includes articles on coalition activities, fleet and stakeholder success stories, and helpful resources.
Date: July 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Renewable Hydrogen: Integration, Validation, and Demonstration (open access)

Renewable Hydrogen: Integration, Validation, and Demonstration

This paper is about producing hydrogen through the electrolysis of water and using the hydrogen in a fuel cell or internal combustion engine generator to produce electricity during times of peak demand, or as a transportation fuel.
Date: July 1, 2008
Creator: Harrison, K. W. & Martin, G. D.
Object Type: Article
System: The UNT Digital Library
Test Plan for Long-Term Operation of a Ten-Cell High Temperature Electrolysis Stack (open access)

Test Plan for Long-Term Operation of a Ten-Cell High Temperature Electrolysis Stack

This document defines a test plan for a long-term (2500 Hour) test of a ten-cell high-temperature electrolysis stack to be performed at INL during FY09 under the Nuclear Hydrogen Initiative. This test was originally planned for FY08, but was removed from our work scope as a result of the severe budget cuts in the FY08 NHI Program. The purpose of this test is to evaluate stack performance degradation over a relatively long time period and to attempt to identify some of the degradation mechanisms via post-test examination. This test will be performed using a planar ten-cell Ceramatec stack, with each cell having dimensions of 10 cm × 10 cm. The specific makeup of the stack will be based on the results of a series of shorter duration ten-cell stack tests being performed during FY08, funded by NGNP. This series of tests was aimed at evaluating stack performance with different interconnect materials and coatings and with or without brazed edge rails. The best performing stack from the FY08 series, in which five different interconnect/coating/edge rail combinations were tested, will be selected for the FY09 long-term test described herein.
Date: July 1, 2008
Creator: O'Brien, James E.; Stoots, Carl M. & Herring, J. Stephen
Object Type: Report
System: The UNT Digital Library
Improved Measurement of CP Observables in B- to D0_CP K- Decays (open access)

Improved Measurement of CP Observables in B- to D0_CP K- Decays

We present a study of the decay B{sup -} {yields} D{sub (CP)}{sup 0}K{sup -} and its charge conjugate, where D{sub (CP)}{sup 0} is reconstructed in both a non-CP flavor eigenstate and in CP (CP-even and CP-odd) eigenstates, based on a sample of 382 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. We measure the direct CP asymmetries A{sub CP{+-}} and the ratios of the branching fractions R{sub CP{+-}}: A{sub CP+} = 0.27 {+-} 0.09(stat) {+-} 0.04(syst), A{sub CP-} = -0.09 {+-} 0.09(stat) {+-} 0.02(syst), R{sub CP+} = 1.06 {+-} 0.10(stat) {+-} 0.05(syst), R{sub CP-} = 1.03 {+-} 0.10(stat) {+-} 0.05(syst). These results will help to better constrain the gamma phase parameter of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.
Date: July 1, 2008
Creator: Aubert, Bernard; Bona, Marcella; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Run05 Proton Beam Polarization Measurements by pC-Polarimeter (ver. 1.1) (open access)

Run05 Proton Beam Polarization Measurements by pC-Polarimeter (ver. 1.1)

The polarization of the proton beams [1, 2] at the Relativistic Heavy Ion Collider (RHIC)[3] RHIC ring. The H-Jet polarimeter is located at the collision point allowing measurements of absolute normalization is provided by the hydrogen polarimeter, which measures over 1 {approx} 2 another measurement rather than measuring the absolute polarization. both beams. Two identical pC-polarimeters are equipped in the yellow and blue rings, where carbon ribbon target, providing fast feedback to beam operations and experiments. The days to obtain {approx} 5% statistical uncertainty (in Run05). Thus, the operation of the carbon is measured using both an atomic beam source hydrogen gas jet (H-Jet)[4, 5] and proton-carbon polarimeters was focused on better control of relative stability between one measurement to statistical accuracy within 20 to 30 seconds using an ultra-thin (typically 6 {approx} 8 {micro}g/cm{sup 2}) the rings are separated. The pC-polarimeter measures relative polarization to a few percent.
Date: July 1, 2008
Creator: Nakagawa,I.; Alekseev, I.; Bazilevsky, A.; Bravar, A.; Bunce, G.; Dhawan, S. et al.
Object Type: Report
System: The UNT Digital Library
Save Energy Now (SEN) Assessment Helps Expand Energy Management Program at Shaw Industries: Flooring Company Saves $872,000 Annually by Improving Steam System Efficiency (open access)

Save Energy Now (SEN) Assessment Helps Expand Energy Management Program at Shaw Industries: Flooring Company Saves $872,000 Annually by Improving Steam System Efficiency

This case study describes how the Shaw Industries plant #20 in Dalton, Georgia, achieved annual savings of $872,000 and 93,000 MMBtu after receiving a DOE Save Energy Now energy assessment and implementing recommendations to improve the efficiency of its steam system.
Date: July 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Simulating the Growth of a Disk Galaxy and its Supermassive Black Hole in a Cosmological Simulating the Growth of a Disk Galaxy and its Supermassive Black Hole in a Cosmological Context (open access)

Simulating the Growth of a Disk Galaxy and its Supermassive Black Hole in a Cosmological Simulating the Growth of a Disk Galaxy and its Supermassive Black Hole in a Cosmological Context

Supermassive black holes (SMBHs) are ubiquitous in the centers of galaxies. Their formation and subsequent evolution is inextricably linked to that of their host galaxies, and the study of galaxy formation is incomplete without the inclusion of SMBHs. The present work seeks to understand the growth and evolution of SMBHs through their interaction with the host galaxy and its environment. In the first part of the thesis (Chap. 2 and 3), we combine a simple semi-analytic model of outflows from active galactic nuclei (AGN) with a simulated dark matter density distribution to study the impact of SMBH feedback on cosmological scales. We find that constraints can be placed on the kinetic efficiency of such feedback using observations of the filling fraction of the Ly{alpha} forest. We also find that AGN feedback is energetic enough to redistribute baryons over cosmological distances, having potentially significant effects on the interpretation of cosmological data which are sensitive to the total matter density distribution (e.g. weak lensing). However, truly assessing the impact of AGN feedback in the universe necessitates large-dynamic range simulations with extensive treatment of baryonic physics to first model the fueling of SMBHs. In the second part of the thesis (Chap. 4-6) we …
Date: July 1, 2008
Creator: Levine, Robyn Deborah & /JILA, Boulder
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Searches for Higgs Bosons beyond the Standard Model at the Tevatron Collider (open access)

Searches for Higgs Bosons beyond the Standard Model at the Tevatron Collider

None
Date: July 1, 2008
Creator: Filthaut, F. & U., /Nijmegen
Object Type: Article
System: The UNT Digital Library
The Dark Energy Survey Data Management System (open access)

The Dark Energy Survey Data Management System

The Dark Energy Survey (DES) collaboration will study cosmic acceleration with a 5000 deg2 griZY survey in the southern sky over 525 nights from 2011-2016. The DES data management (DESDM) system will be used to process and archive these data and the resulting science ready data products. The DESDM system consists of an integrated archive, a processing framework, an ensemble of astronomy codes and a data access framework. We are developing the DESDM system for operation in the high performance computing (HPC) environments at the National Center for Supercomputing Applications (NCSA) and Fermilab. Operating the DESDM system in an HPC environment offers both speed and flexibility. We will employ it for our regular nightly processing needs, and for more compute-intensive tasks such as large scale image coaddition campaigns, extraction of weak lensing shear from the full survey dataset, and massive seasonal reprocessing of the DES data. Data products will be available to the Collaboration and later to the public through a virtual-observatory compatible web portal. Our approach leverages investments in publicly available HPC systems, greatly reducing hardware and maintenance costs to the project, which must deploy and maintain only the storage, database platforms and orchestration and web portal nodes that …
Date: July 1, 2008
Creator: Mohr, Joseph J.; /Illinois U., Urbana, Astron. Dept. /Illinois U., Urbana; Barkhouse, Wayne; U., /North Dakota; Beldica, Cristina; /Illinois U., Urbana et al.
Object Type: Article
System: The UNT Digital Library
A Tariff for Reactive Power (open access)

A Tariff for Reactive Power

Two kinds of power are required to operate an electric power system: real power, measured in watts, and reactive power, measured in volt-amperes reactive or VARs. Reactive power supply is one of a class of power system reliability services collectively known as ancillary services, and is essential for the reliable operation of the bulk power system. Reactive power flows when current leads or lags behind voltage. Typically, the current in a distribution system lags behind voltage because of inductive loads such as motors. Reactive power flow wastes energy and capacity and causes voltage droop. To correct lagging power flow, leading reactive power (current leading voltage) is supplied to bring the current into phase with voltage. When the current is in phase with voltage, there is a reduction in system losses, an increase in system capacity, and a rise in voltage. Reactive power can be supplied from either static or dynamic VAR sources. Static sources are typically transmission and distribution equipment, such as capacitors at substations, and their cost has historically been included in the revenue requirement of the transmission operator (TO), and recovered through cost-of-service rates. By contrast, dynamic sources are typically generators capable of producing variable levels of reactive …
Date: July 1, 2008
Creator: Kueck, John D; Kirby, Brendan J; Li, Fangxing; Tufon, Christopher & Isemonger, Alan
Object Type: Report
System: The UNT Digital Library
When Should Inverter-Duty Motors Be Specified? (open access)

When Should Inverter-Duty Motors Be Specified?

This is one in a series of tip sheets to help manufacturers optimize their industrial motor and motor-driven systems.
Date: July 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
IFC BIM-Based Methodology for Semi-Automated Building Energy Performance Simulation (open access)

IFC BIM-Based Methodology for Semi-Automated Building Energy Performance Simulation

Building energy performance (BEP) simulation is still rarely used in building design, commissioning and operations. The process is too costly and too labor intensive, and it takes too long to deliver results. Its quantitative results are not reproducible due to arbitrary decisions and assumptions made in simulation model definition, and can be trusted only under special circumstances. A methodology to semi-automate BEP simulation preparation and execution makes this process much more effective. It incorporates principles of information science and aims to eliminate inappropriate human intervention that results in subjective and arbitrary decisions. This is achieved by automating every part of the BEP modeling and simulation process that can be automated, by relying on data from original sources, and by making any necessary data transformation rule-based and automated. This paper describes the new methodology and its relationship to IFC-based BIM and software interoperability. It identifies five steps that are critical to its implementation, and shows what part of the methodology can be applied today. The paper concludes with a discussion of application to simulation with EnergyPlus, and describes data transformation rules embedded in the new Geometry Simplification Tool (GST).
Date: July 1, 2008
Creator: Bazjanac, Vladimir
Object Type: Article
System: The UNT Digital Library
Plug-In Hybrid Electric Vehicle Value Proposition Study: Phase 1, Task 3: Technical Requirements and Procedure for Evaluation of One Scenario (open access)

Plug-In Hybrid Electric Vehicle Value Proposition Study: Phase 1, Task 3: Technical Requirements and Procedure for Evaluation of One Scenario

In Task 2, the project team designed the Phase 1 case study to represent the 'baseline' plug-in hybrid electric vehicle (PHEV) fleet of 2030 that investigates the effects of seventeen (17) value propositions (see Table 1 for complete list). By creating a 'baseline' scenario, a consistent set of assumptions and model parameters can be established for use in more elaborate Phase 2 case studies. The project team chose southern California as the Phase 1 case study location because the economic, environmental, social, and regulatory conditions are conducive to the advantages of PHEVs. Assuming steady growth of PHEV sales over the next two decades, PHEVs are postulated to comprise approximately 10% of the area's private vehicles (about 1,000,000 vehicles) in 2030. New PHEV models introduced in 2030 are anticipated to contain lithium-ion batteries and be classified by a blended mileage description (e.g., 100 mpg, 150 mpg) that demonstrates a battery size equivalence of a PHEV-30. Task 3 includes the determination of data, models, and analysis procedures required to evaluate the Phase 1 case study scenario. Some existing models have been adapted to accommodate the analysis of the business model and establish relationships between costs and value to the respective consumers. Other …
Date: July 1, 2008
Creator: Sikes, Karen R; Hinds, Shaun; Hadley, Stanton W; McGill, Ralph N; Markel, Lawrence C; Ziegler, Richard E et al.
Object Type: Report
System: The UNT Digital Library