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The Absolute, Relative and Multi-Wavelength Calibration of the Pierre Auger Observatory Fluorescence Detectors (open access)

The Absolute, Relative and Multi-Wavelength Calibration of the Pierre Auger Observatory Fluorescence Detectors

Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a 375 nm light source at the telescope aperture. This end-to-end technique accounts for the combined effects of all detector components in a single measurement. The relative response has been measured at wavelengths of 320, 337, 355, 380 and 405 nm, defining a spectral response curve which has been normalized to the absolute calibration. Before and after each night of data taking a relative calibration of the phototubes is performed. This relative calibration is used to track both short and long term changes in the detector's response. A cross check of the calibration in some phototubes is performed using an independent laser technique. Overall uncertainties, current results and future plans are discussed.
Date: August 1, 2007
Creator: Knapik, R.; Bauleo, P.; Becker, B.R.; Brack, J.; Caruso, R.; Fratte, C.Delle et al.
Object Type: Article
System: The UNT Digital Library
Accidental Drop of a Carbon Steel/Lead Shipping Cask (HFEF 14) at Low Temperatures (open access)

Accidental Drop of a Carbon Steel/Lead Shipping Cask (HFEF 14) at Low Temperatures

A shielded cask is used to transport radioactive materials between facilities at the Idaho National Laboratory. The cask was fabricated with an outer and inner shell of A36 carbon steel with lead poured in the annular space between the shells to provide radiation shielding. Carbon steel is known to be susceptible to low-temperature brittle fracture under impact loading. This paper will present the analysis results representing postulated transportation accidents during on-site transfers of the cask at subzero temperatures. The accident scenarios were based on a series of cask drops onto a rigid surface from a height of 1.83m (6 ft.) Finite element models of the cask and its contents were solved and post processed using the ABAQUS software. Each model was examined for failure to contain radioactive materials and/or significant loss of radiation shielding. Results of these analyses show that the body of the cask exhibits considerable ruggedness and will remain largely intact after the impact. There will be deformation of the main cask body with localized brittle failure of the cask outer shell and door structure. The cask payload outer waste can remains in the cask but will experience some permanent plastic deformation in each drop. It will not …
Date: August 1, 2007
Creator: Hawkes, Brian D. & Nitzel, Michael E.
Object Type: Article
System: The UNT Digital Library
Activities and Accomplishments in MY 2006/FY 2007 (open access)

Activities and Accomplishments in MY 2006/FY 2007

Document details the compliance activities of EPAct-covered state and alternative fuel provider fleets in model year 2006.
Date: August 1, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced Modeling of Renewable Energy Market Dynamics: May 2006 (open access)

Advanced Modeling of Renewable Energy Market Dynamics: May 2006

This report documents a year-long academic project, presenting selected techniques for analysis of market growth, penetration, and forecasting applicable to renewable energy technologies. Existing mathematical models were modified to incorporate the effects of fiscal policies and were evaluated using available data. The modifications were made based on research and classification of current mathematical models used for predicting market penetration. An analysis of the results was carried out, based on available data. MATLAB versions of existing and new models were developed for research and policy analysis.
Date: August 1, 2007
Creator: Evans, M.; Little, R.; Lloyd, K.; Malikov, G.; Passolt, G.; Arent, D. et al.
Object Type: Report
System: The UNT Digital Library
Advantages and Disadvantages of Physiological Assessment For Next Generation Control Room Design (open access)

Advantages and Disadvantages of Physiological Assessment For Next Generation Control Room Design

Abstract - We propose using non-obtrusive physiological assessment (e.g., eye tracking,) to assess human information processing errors (e.g., loss of vigilance) and limitations (e.g., workload) for advanced energy systems early in the design process. This physiological approach for assessing risk will circumvent many limitations of current risk methodologies such as subjective rating (e.g., rater’s biases) and performance modeling (e.g., risk assessment is scripted and is based upon the individual modeler’s judgment). Key uses will be to evaluate (early in the design process) novel control room equipment and configurations as well as newly developed automated systems that will inevitably place a high information load on operators. The physiological risk assessment tool will allow better precision in pinpointing problematic design issues and will provide a “real-time” assessment of risk. Furthermore, this physiological approach would extend the state-of-the-art of human reliability methods from a “static” measure to more “dynamic.” This paper will discuss a broad range of the current popular online performance gauges as well as its advantages and disadvantages for use in next generation control room.
Date: August 1, 2007
Creator: Tran, Tuan Q.; Boring, Ronald L.; Dudenhoeffer, Donald D.; Hallbert, Bruce P; Keller, M. David & Anderson, Tessa M.
Object Type: Article
System: The UNT Digital Library
Aeroelastic Instabilities of Large Offshore and Onshore Wind Turbines: Preprint (open access)

Aeroelastic Instabilities of Large Offshore and Onshore Wind Turbines: Preprint

This paper examines the aeroelastic stability of a 5-MW conceptual wind turbine mounted on a floating barge and presents results for onshore and offshore configurations for various conditions.
Date: August 1, 2007
Creator: Bir, G. & Jonkman, J.
Object Type: Article
System: The UNT Digital Library
Agriculture in U.S. Free Trade Agreements: Trade with Current and Prospective Partners, Impact, and Issues (open access)

Agriculture in U.S. Free Trade Agreements: Trade with Current and Prospective Partners, Impact, and Issues

This report discusses the trade in agricultural products, which is one of the difficult issues negotiators face in concluding free trade agreements (FTAs). The report also deals with food safety and animal/plant health matters.
Date: August 1, 2007
Creator: Jurenas, Remy
Object Type: Report
System: The UNT Digital Library
AGS BPM Tests (open access)

AGS BPM Tests

N/A
Date: August 1, 2007
Creator: P., Menga; Ahrens, L. & Schroeder, R.
Object Type: Report
System: The UNT Digital Library
Air Distribution Effectiveness for Different MechanicalVentilation Systems (open access)

Air Distribution Effectiveness for Different MechanicalVentilation Systems

The purpose of ventilation is to dilute indoor contaminants that an occupant is exposed to. In a multi-zone environment such as a house, there will be different dilution rates and different source strengths in every zone. Most US homes have central HVAC systems, which tend to mix conditions between zones. Different types of ventilation systems will provide different amounts of dilution depending on the effectiveness of their air distribution systems and the location of sources and occupants. This paper will report on work being done to both model the impact of different systems and measurements using a new multi-tracer measurement system that has the capacity to measure not only the flow of outdoor air to each zone, but zone-to-zone transport. The ultimate objective of this project is to determine the effectiveness of different systems so that appropriate adjustments can be made in residential ventilation standards such as ASHRAE Standard 62.2.
Date: August 1, 2007
Creator: Sherman, Max H. & Walker, Iain S.
Object Type: Article
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 109, No. 53, Ed. 1 Wednesday, August 1, 2007 (open access)

The Altus Times (Altus, Okla.), Vol. 109, No. 53, Ed. 1 Wednesday, August 1, 2007

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 1, 2007
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analysis of Buoyancy-Driven Ventilation of Hydrogen from Buildings: Preprint (open access)

Analysis of Buoyancy-Driven Ventilation of Hydrogen from Buildings: Preprint

When hydrogen gas is used or stored within a building, as with a hydrogen-powered vehicle parked in a residential garage, any leakage of unignited H2 will mix with indoor air and may form a flammable mixture. One approach to safety engineering relies on buoyancy-driven, passive ventilation of H2 from the building through vents to the outside.
Date: August 1, 2007
Creator: Barley, C. D.; Gawlik, K.; Ohi, J. & Hewett, R.
Object Type: Article
System: The UNT Digital Library
ANALYSIS OF SAFETY RELIEF VALVE PROOF TEST DATA TO OPTIMIZE LIFECYCLE MAINTENANCE COSTS (open access)

ANALYSIS OF SAFETY RELIEF VALVE PROOF TEST DATA TO OPTIMIZE LIFECYCLE MAINTENANCE COSTS

Proof test results were analyzed and compared with a proposed life cycle curve or hazard function and the limit of useful life. Relief valve proof testing procedures, statistical modeling, data collection processes, and time-in-service trends are presented. The resulting analysis of test data allows for the estimation of the PFD. Extended maintenance intervals to the limit of useful life as well as methodologies and practices for improving relief valve performance and reliability are discussed. A generic cost-benefit analysis and an expected life cycle cost reduction concludes that $90 million maintenance dollars might be avoided for a population of 3000 valves over 20 years.
Date: August 1, 2007
Creator: Gross, Robert & Harris, Stephen
Object Type: Article
System: The UNT Digital Library
Anatomy of a SAR impulse response. (open access)

Anatomy of a SAR impulse response.

A principal measure of Synthetic Aperture Radar (SAR) image quality is the manifestation in the SAR image of a spatial impulse, that is, the SAR's Impulse Response (IPR). IPR requirements direct certain design decisions in a SAR. Anomalies in the IPR can point to specific anomalous behavior in the radar's hardware and/or software.
Date: August 1, 2007
Creator: Doerry, Armin Walter
Object Type: Report
System: The UNT Digital Library

[Andrea Robledo and others in MC offices]

A photograph of a group of people gathered together in the UNT Multicultural Center offices. Andrea Robledo is seated at a table with students and snacks. Computer desk, private offices, the printing room, and decorations are all visible behind her.
Date: August 1, 2007
Creator: University of North Texas. Multicultural Center.
Object Type: Photograph
System: The UNT Digital Library
APDEC Final Report, August, 2007 (open access)

APDEC Final Report, August, 2007

Final report on grant funded through the SciDAC program as part of the APDEC grant at LBNL.
Date: August 1, 2007
Creator: LeVeque, Randall J.
Object Type: Text
System: The UNT Digital Library
Application of direct-fitting, mass-integral, and multi-ratemethods to analysis of flowing fluid electric conductivity logs fromHoronobe, Japan (open access)

Application of direct-fitting, mass-integral, and multi-ratemethods to analysis of flowing fluid electric conductivity logs fromHoronobe, Japan

The flowing fluid electric conductivity (FFEC) loggingmethod is an efficient way to provide information on the depths,salinities, and transmissivities of individual conductive featuresintercepted by a borehole, without the use of specialized probes. Usingit in a multiple-flow-rate mode allows, in addition, an estimate of theinherent "far-field" pressure heads in each of the conductive features.The multi-rate method was successfully applied to a 500-m borehole in agranitic formation and reported recently. The present paper presents theapplication of the method to two zones within a 1000-m borehole insedimentary rock, which produced, for each zone, three sets of logs atdifferent pumping rates, each set measured over a period of about oneday. The data sets involve a number of complications, such as variablewell diameter, free water table decline in the well, and effects ofdrilling mud. To analyze data from this borehole, we apply varioustechniques that have been developed for analyzing FFEC logs:direct-fitting, mass-integral, and the multi-rate method mentioned above.In spite of complications associated with the tests, analysis of the datais able to identify 44 hydraulically conducting fractures distributedover the depth interval 150-775 meters below ground surface. Thesalinities (in FEC), and transmissivities and pressure heads (indimensionless form) of these 44 features are obtained and found to varysignificantly …
Date: August 1, 2007
Creator: Doughty, C.; Tsang, C.-F.; Hatanaka, K.; Yabuuchi, S. & Kurikami, H.
Object Type: Article
System: The UNT Digital Library
Asian Tracer Experiment and Atmospheric Modeling (TEAM) Project: Draft Field Work Plan for the Asian Long-Range Tracer Experiment (open access)

Asian Tracer Experiment and Atmospheric Modeling (TEAM) Project: Draft Field Work Plan for the Asian Long-Range Tracer Experiment

This report provides an experimental plan for a proposed Asian long-range tracer study as part of the international Tracer Experiment and Atmospheric Modeling (TEAM) Project. The TEAM partners are China, Japan, South Korea and the United States. Optimal times of year to conduct the study, meteorological measurements needed, proposed tracer release locations, proposed tracer sampling locations and the proposed durations of tracer releases and subsequent sampling are given. Also given are the activities necessary to prepare for the study and the schedule for completing the preparation activities leading to conducting the actual field operations. This report is intended to provide the TEAM members with the information necessary for planning and conducting the Asian long-range tracer study. The experimental plan is proposed, at this time, to describe the efforts necessary to conduct the Asian long-range tracer study, and the plan will undoubtedly be revised and refined as the planning goes forward over the next year.
Date: August 1, 2007
Creator: Allwine, K Jerry & Flaherty, Julia E.
Object Type: Report
System: The UNT Digital Library
Aviation Finance: Observations on the Current FAA Funding Structure's Support for Aviation Activities, Issues Affecting Future Costs, and Proposed Funding Changes (open access)

Aviation Finance: Observations on the Current FAA Funding Structure's Support for Aviation Activities, Issues Affecting Future Costs, and Proposed Funding Changes

Testimony issued by the Government Accountability Office with an abstract that begins "The Federal Aviation Administration (FAA) operates one of the safest air transportation systems in the world, but this system is under growing strain as the demand for air travel increases. Recognizing the need to transform this system, Congress created the Joint Planning and Development Office (JPDO), housed within FAA, to plan and develop the Next Generation Air Transportation System (NextGen). The current authorization for FAA, the Airport and Airway Trust Fund (Trust Fund), and most of the excise taxes that support the Trust Fund will expire September 30, 2007. Several proposals, including two reauthorization bills--H.R. 2881 and S. 1300--identify various funding sources for FAA activities, including NextGen. Among these are current excise taxes, fees, and flight surcharges. Concerned about the need for stable, sustainable financing for the nation's multibillion-dollar transportation infrastructure investments, including NextGen, GAO has designated transportation financing as high risk. GAO's statement addresses (1) the extent to which the current funding structure can support FAA's activities, including NextGen, (2) issues that could affect the overall cost of NextGen, and (3) the implications of selected proposals to fund aviation activities. The statement is based on recent GAO …
Date: August 1, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
A Bacterial Metapopulation Adapts Locally to Phage Predation Despite Global Dispersal (open access)

A Bacterial Metapopulation Adapts Locally to Phage Predation Despite Global Dispersal

This report talks about Bacterial Metapopulation Adapts Locally to Phage Predation Despite Global Dispersal
Date: August 1, 2007
Creator: Kunin, Victor; He, S.; Warnecke, Falk; Peterson, S.B.; Garcia Martin, H.; Haynes, M. et al.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 247, Ed. 1 Wednesday, August 1, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 247, Ed. 1 Wednesday, August 1, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 1, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Binery Pseudo-Random Grating as a Standard Test Surface for Measurement of Modulation Transfer Function of Interferometric Microscopes (open access)

Binery Pseudo-Random Grating as a Standard Test Surface for Measurement of Modulation Transfer Function of Interferometric Microscopes

The task of designing high performance X-ray optical systems requires the development of sophisticated X-ray scattering calculations based on rigorous information about the optics. One of the most insightful approaches to these calculations is based on the power spectral density (PSD) distribution of the surface height. The major problem of measurement of a PSD distribution with an interferometric and/or atomic force microscope arises due to the unknown Modulation Transfer Function (MTF) of the instruments. The MTF characterizes the perturbation of the PSD distribution at higher spatial frequencies. Here, we describe a new method and dedicated test surfaces for calibration of the MTF of a microscope. The method is based on use of a specially designed Binary Pseudo-random (BPR) grating. Comparison of a theoretically calculated PSD spectrum of a BPR grating with a spectrum measured with the grating provides the desired calibration of the instrumental MTF. The theoretical background of the method, as well as results of experimental investigations are presented.
Date: August 1, 2007
Creator: Yashchuk, V. V.; McKinney, W. R. & Takacs, P. Z.
Object Type: Article
System: The UNT Digital Library
Boosted Fast Flux Loop Alternative Cooling Assessment (open access)

Boosted Fast Flux Loop Alternative Cooling Assessment

The Gas Test Loop (GTL) Project was instituted to develop the means for conducting fast neutron irradiation tests in a domestic radiation facility. It made use of booster fuel to achieve the high neutron flux, a hafnium thermal neutron absorber to attain the high fast-to-thermal flux ratio, a mixed gas temperature control system for maintaining experiment temperatures, and a compressed gas cooling system to remove heat from the experiment capsules and the hafnium thermal neutron absorber. This GTL system was determined to provide a fast (E > 0.1 MeV) flux greater than 1.0E+15 n/cm2-s with a fast-to-thermal flux ratio in the vicinity of 40. However, the estimated system acquisition cost from earlier studies was deemed to be high. That cost was strongly influenced by the compressed gas cooling system for experiment heat removal. Designers were challenged to find a less expensive way to achieve the required cooling. This report documents the results of the investigation leading to an alternatively cooled configuration, referred to now as the Boosted Fast Flux Loop (BFFL). This configuration relies on a composite material comprised of hafnium aluminide (Al3Hf) in an aluminum matrix to transfer heat from the experiment to pressurized water cooling channels while at …
Date: August 1, 2007
Creator: Longhurst, Glen R.; Guillen, Donna Post; Parry, James R.; Porter, Douglas L. & Wallace, Bruce W.
Object Type: Report
System: The UNT Digital Library
CAN SORBENT-BASED GAS PHASE AIR CLEANING FOR VOCS SUBSTITUTE FOR VENTILATION IN COMMERCIAL BUILDINGS? (open access)

CAN SORBENT-BASED GAS PHASE AIR CLEANING FOR VOCS SUBSTITUTE FOR VENTILATION IN COMMERCIAL BUILDINGS?

This paper reviews current knowledge about the suitability of sorbent-based air cleaning for removing volatile organic compounds (VOCs) from the air in commercial buildings, as needed to enable reductions in ventilation rates and associated energy savings. The principles of sorbent air cleaning are introduced, criteria are suggested for sorbent systems that can counteract indoor VOC concentration increases from reduced ventilation, major findings from research on sorbent performance for this application are summarized, and related priority research needs are identified. Major conclusions include: sorbent systems can remove a broad range of VOCs with moderate to high efficiency, sorbent technologies perform effectively when challenged with VOCs at the low concentrations present indoors, and there is a large uncertainty about the lifetime and associated costs of sorbent air cleaning systems when used in commercial buildings for indoor VOC control. Suggested priority research includes: experiments to determine sorbent system VOC removal efficiencies and lifetimes considering the broad range and low concentration of VOCs indoors; evaluations of in-situ regeneration of sorbents; and an updated analysis of the cost of sorbent air cleaning relative to the cost of ventilation.
Date: August 1, 2007
Creator: Fisk, William & Fisk, William J.
Object Type: Article
System: The UNT Digital Library
Capitol Power Plant: Status of Utility Tunnel Projects (open access)

Capitol Power Plant: Status of Utility Tunnel Projects

Testimony issued by the Government Accountability Office with an abstract that begins "The Architect of the Capitol (AOC), through the Capitol Power Plant, operates five walkable utility tunnels containing steam and chilled water pipes associated with serving the heating and cooling requirements of the U.S. Capitol and over 20 surrounding facilities. In our work last fall, we addressed conditions in the tunnels and AOC's plans for addressing them. The Office of Compliance (OOC), which is responsible for advancing safety, health, and workplace rights in the legislative branch, and the tunnel workers had raised concerns about health and safety issues in the tunnels. As a result of these concerns, in January 2006, OOC issued citations for and asked AOC to address a potential asbestos hazard and heat stress conditions in the tunnels. In addition, in February 2006, OOC filed a complaint against AOC concerning hazards in the tunnels, including falling concrete, an inadequate communication system for these confined spaces, and inadequate escape exits (egresses). According to OOC officials, these conditions had been brought to AOC's attention by OOC inspectors as early as 1999, but AOC had not made sufficient progress in addressing them, and conditions in the tunnels had deteriorated further. …
Date: August 1, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library