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An Algebraic Approach to the Evolution of Emittances upon Crossing the Linear Coupling Difference Resonance (open access)

An Algebraic Approach to the Evolution of Emittances upon Crossing the Linear Coupling Difference Resonance

One of the hallmarks of linear coupling is the resonant exchange of oscillation amplitude between the horizontal and vertical planes when the difference between the unperturbed tunes is close to an integer. The standard derivation of this phenomenon (known as the difference resonance) can be found, for example, in the classic papers of Guignard [1, 2]. One starts with an uncoupled lattice and adds a linear perturbation that couples the two planes. The equations of motion are expressed in hamiltonian form. As the difference between the unperturbed tunes approaches an integer, one finds that the perturbing terms in the hamiltonian can be divided into terms that oscillate slowly and ones that oscillate rapidly. The rapidly oscillating terms are discarded or transformed to higher order with an appropriate canonical transformation. The resulting approximate hamiltonian gives equations of motion that clearly exhibit the exchange of oscillation amplitude between the two planes. If, instead of the hamiltonian, one is given the four-by-four matrix for one turn around a synchrotron, then one has the complete solution for the turn-by-turn (TBT) motion. However, the conditions for the phenomenon of amplitude exchange are not obvious from a casual inspection of the matrix. These conditions and those …
Date: September 1, 2008
Creator: Gardner,C.
System: The UNT Digital Library
An Algebraic Approach to the Evolution of Emittances upon Crossing the Linear Coupling Difference Resonance (open access)

An Algebraic Approach to the Evolution of Emittances upon Crossing the Linear Coupling Difference Resonance

N/A
Date: September 1, 2008
Creator: Gardner, C. J.
System: The UNT Digital Library
Alignment of the Near Detector scintillator modules using cosmic ray muons (open access)

Alignment of the Near Detector scintillator modules using cosmic ray muons

The authors describe the procedures and the results of the first alignment of the Near Detector. Using 15.5 million cosmic ray muon tracks, collected from October, 2004 through early january, 2005, they derive the effective transverse positions of the calorimeter scintillator modules. The residuals from straight line fits indicate that the current alignment has achieved better than 1 mm precision. They estimate the size of the remaining misalignment and using tracks recorded with a magnetic field test the effect of the magnetic field on the alignment.
Date: May 1, 2008
Creator: Ospanov, Rustem; Lang, Karol & U., /Texas
System: The UNT Digital Library
Alternative Fuels and Advanced Technology Vehicles: Issues in Congress (open access)

Alternative Fuels and Advanced Technology Vehicles: Issues in Congress

This report provides an overview of current issues surrounding alternative fuels and advanced technology vehicles.
Date: February 1, 2008
Creator: Yacobucci, Brent D.
System: The UNT Digital Library
The Alternative Minimum Tax for Individuals: Legislative Activity in the 110th Congress (open access)

The Alternative Minimum Tax for Individuals: Legislative Activity in the 110th Congress

The alternative minimum tax (AMT) for individuals was originally enacted to ensure that all taxpayers, especially high-income taxpayers, pay at least a minimum amount of federal taxes. However, the AMT is not indexed for inflation, and this factor, combined with recent reductions in the regular income tax, has greatly expanded the potential impact of the AMT. This report explains legislation for the FY2009 budget compromise, which includes an offset AMT patch.
Date: July 1, 2008
Creator: Maguire, Steven & Teefy, Jennifer
System: The UNT Digital Library
Analyses to Verify and Improve the Accuracy of the Manufactured Home Energy Audit (MHEA) (open access)

Analyses to Verify and Improve the Accuracy of the Manufactured Home Energy Audit (MHEA)

A series of analyses were performed to determine the reasons that the Manufactured Home Energy Audit (MHEA) over predicted space-heating energy savings as measured in a recent field test and to develop appropriate corrections to improve its performance. The study used the Home Energy Rating System (HERS) Building Energy Simulation Test (BESTEST) to verify that MHEA accurately calculates the UA-values of mobile home envelope components and space-heating energy loads as compared with other, well-accepted hourly energy simulation programs. The study also used the Procedures for Verification of RESNET Accredited HERS Software Tools to determine that MHEA accurately calculates space-heating energy consumptions for gas furnaces, heat pumps, and electric-resistance furnaces. Even though MHEA's calculations were shown to be correct from an engineering point of view, three modifications to MHEA's algorithms and use of a 0.6 correction factor were incorporated into MHEA to true-up its predicted savings to values measured in a recent field test. A simulated use of the revised version of MHEA in a weatherization program revealed that MHEA would likely still recommend a significant number of cost-effective weatherization measures in mobile homes (including ceiling, floor, and even wall insulation and far fewer storm windows). Based on the findings from …
Date: December 1, 2008
Creator: Ternes, Mark P & Gettings, Michael B
System: The UNT Digital Library
Analysis and Measurement of Bubble Dynamics and Associated Flow Field in Subcooled Nucleate Boiling Flows (open access)

Analysis and Measurement of Bubble Dynamics and Associated Flow Field in Subcooled Nucleate Boiling Flows

In recent years, subooled nucleate boiling (SNB) has attrcted expanding research interest owing to the emergence of axial offset anomaly (AOA) or crud-induced power shigt (CIPS) in many operating US PWRs, which is an unexpected deviation in the core axial power distribution from the predicted power curves. Research indicates that the formation of the crud, which directly leads to AOA phenomena, results from the presence of the subcooled nucleate boiling, and is especially realted to bubble motion occurring in the core region.
Date: October 1, 2008
Creator: Jones, Barclay G.
System: The UNT Digital Library
Analysis of Fracture in Cores from the Tuff Confining Unit beneath Yucca Flat, Nevada Test Site (open access)

Analysis of Fracture in Cores from the Tuff Confining Unit beneath Yucca Flat, Nevada Test Site

The role fractures play in the movement of groundwater through zeolitic tuffs that form the tuff confining unit (TCU) beneath Yucca Flat, Nevada Test Site, is poorly known. This is an important uncertainty, because beneath most of Yucca Flat the TCU lies between the sources of radionuclide contaminants produced by historic underground nuclear testing and the regional carbonate aquifer. To gain a better understanding of the role fractures play in the movement of groundwater and radionuclides through the TCU beneath Yucca Flat, a fracture analysis focusing on hydraulic properties was performed on conventional cores from four vertical exploratory holes in Area 7 of Yucca Flat that fully penetrate the TCU. The results of this study indicate that the TCU is poorly fractured. Fracture density for all fractures is 0.27 fractures per vertical meter of core. For open fractures, or those observed to have some aperture, the density is only 0.06 fractures per vertical meter of core. Open fractures are characterized by apertures ranging from 0.1 to 10 millimeter, and averaging 1.1 millimeter. Aperture typically occurs as small isolated openings along the fracture, accounting for only 10 percent of the fracture volume, the rest being completely healed by secondary minerals. Zeolite …
Date: March 1, 2008
Creator: Prothro, Lance
System: The UNT Digital Library
Analysis of HFIR Dosimetry Experiments Performed in Cycles 400 and 401 (open access)

Analysis of HFIR Dosimetry Experiments Performed in Cycles 400 and 401

The High Flux Isotope Reactor (HFIR) has been in operation at Oak Ridge National Laboratory since 1966. To upgrade and enhance capabilities for neutron science research at the reactor, a larger HB-2 beam tube was installed in April of 2002. To assess, experimentally, the impact of this larger beam tube on radiation damage rates [i.e., displacement-per-atom (dpa) rates] used in vessel life extension studies, dosimetry experiments were performed from April to August 2004 during fuel cycles 400 and 401. This report documents the analysis of the dosimetry experiments and the determination of best-estimate dpa rates. These dpa rates are obtained by performing a least-squares adjustment of calculated neutron and gamma-ray fluxes and the measured responses of radiometric monitors and beryllium helium accumulation fluence monitors. The best-estimate dpa rates provided here will be used to update HFIR pressure vessel life extension studies, which determine the pressure/temperature limits for reactor operation and the HFIR pressure vessel's remaining life. All irradiation parameters given in this report correspond to a reactor power of 85 MW.
Date: September 1, 2008
Creator: Remec, Igor & Baldwin, Charles A.
System: The UNT Digital Library
Analysis of main steam isolation valve leakage in design basis accidents using MELCOR 1.8.6 and RADTRAD. (open access)

Analysis of main steam isolation valve leakage in design basis accidents using MELCOR 1.8.6 and RADTRAD.

Analyses were performed using MELCOR and RADTRAD to investigate main steam isolation valve (MSIV) leakage behavior under design basis accident (DBA) loss-of-coolant (LOCA) conditions that are presumed to have led to a significant core melt accident. Dose to the control room, site boundary and LPZ are examined using both approaches described in current regulatory guidelines as well as analyses based on best estimate source term and system response. At issue is the current practice of using containment airborne aerosol concentrations as a surrogate for the in-vessel aerosol concentration that exists in the near vicinity of the MSIVs. This study finds current practice using the AST-based containment aerosol concentrations for assessing MSIV leakage is non-conservative and conceptually in error. A methodology is proposed that scales the containment aerosol concentration to the expected vessel concentration in order to preserve the simplified use of the AST in assessing containment performance under assumed DBA conditions. This correction is required during the first two hours of the accident while the gap and early in-vessel source terms are present. It is general practice to assume that at {approx}2hrs, recovery actions to reflood the core will have been successful and that further core damage can be avoided. …
Date: October 1, 2008
Creator: Salay, Michael (United States Nuclear Regulatory Commission, Washington, D.C.); Kalinich, Donald A.; Gauntt, Randall O. & Radel, Tracy E.
System: The UNT Digital Library
An analysis of the pull strength behaviors of fine-pitch, flip chip solder interconnections using a Au-Pt-Pd thick film conductor on Low-Temperature, Co-fired Ceramic (LTCC) substrates. (open access)

An analysis of the pull strength behaviors of fine-pitch, flip chip solder interconnections using a Au-Pt-Pd thick film conductor on Low-Temperature, Co-fired Ceramic (LTCC) substrates.

The assembly of the BDYE detector requires the attachment of sixteen silicon (Si) processor dice (eight on the top side; eight on the bottom side) onto a low-temperature, co-fired ceramic (LTCC) substrate using 63Sn-37Pb (wt.%, Sn-Pb) in a double-reflow soldering process (nitrogen). There are 132 solder joints per die. The bond pads were gold-platinum-palladium (71Au-26Pt-3Pd, wt.%) thick film layers fired onto the LTCC in a post-process sequence. The pull strength and failure modes provided the quality metrics for the Sn-Pb solder joints. Pull strengths were measured in both the as-fabricated condition and after exposure to thermal cycling (-55/125 C; 15 min hold times; 20 cycles). Extremely low pull strengths--referred to as the low pull strength phenomenon--were observed intermittently throughout the product build, resulting in added program costs, schedule delays, and a long-term reliability concern for the detector. There was no statistically significant correlation between the low pull strength phenomenon and (1) the LTCC 'sub-floor' lot; (2) grit blasting the LTCC surfaces prior to the post-process steps; (3) the post-process parameters; (4) the conductor pad height (thickness); (5) the dice soldering assembly sequence; or (5) the dice pull test sequence. Formation of an intermetallic compound (IMC)/LTCC interface caused by thick film …
Date: September 1, 2008
Creator: Uribe, Fernando R.; Kilgo, Alice C.; Grazier, John Mark; Vianco, Paul Thomas; Zender, Gary L.; Hlava, Paul Frank et al.
System: The UNT Digital Library
Analysis of the Technical and Economic Potential for Mid-Scale Distributed Wind: December 2007 - October 31, 2008 (open access)

Analysis of the Technical and Economic Potential for Mid-Scale Distributed Wind: December 2007 - October 31, 2008

This report examines the status, restrainers, drivers, and estimated development potential of mid-scale (10 kW - 5000 kW) distributed wind energy projects.
Date: December 1, 2008
Creator: Kwartin, R.; Wolfrum, A.; Granfield, K.; Kagel, A. & Appleton, A.
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.
System: The UNT Digital Library
Analytical Method for the Detection of Ozone Depleting Chemicals (ODC) in Commercial Products Using a Gas Chromatograph with an Electron Capture Detector (GC-ECD) (open access)

Analytical Method for the Detection of Ozone Depleting Chemicals (ODC) in Commercial Products Using a Gas Chromatograph with an Electron Capture Detector (GC-ECD)

This document describes an analytical procedure that was developed for the trace level detection of residual ozone depleting chemicals (ODC) associated with the manufacture of selected commercial products. To ensure the United States meets it obligation under the Montreal Protocol, Congress enacted legislation in 1989 to impose an excise tax on electronic goods imported into the United States that were produced with banned chemicals. This procedure was developed to technically determine if residual ODC chemicals could be detected on electronic circuit boards. The analytical method utilizes a “purge and trap” technique followed by gas chromatography with electron capture detection to capture and analyze the volatile chemicals associated with the matrix. The method describes the procedure, the hardware, operating conditions, calibration, and quality control measures in sufficient detail to allow the capability to be replicated. This document corresponds to internal Standard Operating Procedure (SOP) EFL-130A, Rev 4.
Date: August 1, 2008
Creator: Lee, Richard N.; Dockendorff, Brian P. & Wright, Bob W.
System: The UNT Digital Library
Analytical models for total dose ionization effects in MOS devices. (open access)

Analytical models for total dose ionization effects in MOS devices.

MOS devices are susceptible to damage by ionizing radiation due to charge buildup in gate, field and SOI buried oxides. Under positive bias holes created in the gate oxide will transport to the Si / SiO{sub 2} interface creating oxide-trapped charge. As a result of hole transport and trapping, hydrogen is liberated in the oxide which can create interface-trapped charge. The trapped charge will affect the threshold voltage and degrade the channel mobility. Neutralization of oxidetrapped charge by electron tunneling from the silicon and by thermal emission can take place over long periods of time. Neutralization of interface-trapped charge is not observed at room temperature. Analytical models are developed that account for the principal effects of total dose in MOS devices under different gate bias. The intent is to obtain closed-form solutions that can be used in circuit simulation. Expressions are derived for the aging effects of very low dose rate radiation over long time periods.
Date: August 1, 2008
Creator: Campbell, Phillip Montgomery & Bogdan, Carolyn W.
System: The UNT Digital Library
Analyzing Options for Airborne Emergency Wireless Communications (open access)

Analyzing Options for Airborne Emergency Wireless Communications

In the event of large-scale natural or manmade catastrophic events, access to reliable and enduring commercial communication systems is critical. Hurricane Katrina provided a recent example of the need to ensure communications during a national emergency. To ensure that communication demands are met during these critical times, Idaho National Laboratory (INL) under the guidance of United States Strategic Command has studied infrastructure issues, concerns, and vulnerabilities associated with an airborne wireless communications capability. Such a capability could provide emergency wireless communications until public/commercial nodes can be systematically restored. This report focuses on the airborne cellular restoration concept; analyzing basic infrastructure requirements; identifying related infrastructure issues, concerns, and vulnerabilities and offers recommended solutions.
Date: March 1, 2008
Creator: Schmitt, Michael; Deaton, Juan; Papke, Curt & Cherry, Shane
System: The UNT Digital Library
Animal Agriculture: 2008 Farm Bill Issues (open access)

Animal Agriculture: 2008 Farm Bill Issues

This report discusses a number of animal-related provisions related to the 2008 farm bill. It includes background and specific provisions from the bill for each of the issues and options analyzed in the report: market competition and packer concentration, livestock mandatory price reporting, meat and poultry safety, country-of-origin labeling, animal identification for health protection, animal welfare, feed prices, disaster assistance, and environmental issues. The report also provides a summary comparison of previous farm bills with the 2008 provisions for selected issues.
Date: July 1, 2008
Creator: Becker, Geoffrey S. & Johnson, Renée
System: The UNT Digital Library
Annual Report on U.S. Wind Power Installation, Cost, and Performance Trends: 2007 (Revised) (open access)

Annual Report on U.S. Wind Power Installation, Cost, and Performance Trends: 2007 (Revised)

This report focuses on key trends in the U.S. wind power market, with an emphasis on the latest year, and presents a wealth of data, some of which has not historically been mined by wind power analysts.
Date: May 1, 2008
Creator: Wiser, R. & Bolinger, M.
System: The UNT Digital Library
Annual Technical Progress Report of Radioisotope Power Systems Materials Production and Technology Program Tasks for October 1, 2006 Through September 30, 2007 (open access)

Annual Technical Progress Report of Radioisotope Power Systems Materials Production and Technology Program Tasks for October 1, 2006 Through September 30, 2007

The Office of Radioisotope Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Radioisotope Power Systems for fiscal year (FY) 2007. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.
Date: April 1, 2008
Creator: King, James F
System: The UNT Digital Library
Annual Waste Minimization Summary Report Calendar Year 2007 (open access)

Annual Waste Minimization Summary Report Calendar Year 2007

This report summarizes the waste minimization efforts undertaken by National Security Technologies, LLC (NSTec), for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), during calendar year (CY) 2007. This report was developed in accordance with the requirements of the Nevada Test Site (NTS) Resource Conservation and Recovery Act (RCRA) Permit (number NEV HW0021), and as clarified in a letter dated April 21, 1995, from Paul Liebendorfer of the Nevada Division of Environmental Protection to Donald Elle of the U.S. Department of Energy, Nevada Operations Office. The NNSA/NSO Pollution Prevention (P2) Program establishes a process to reduce the volume and toxicity of waste generated by the NNSA/NSO and ensures that proposed methods of treatment, storage, and/or disposal of waste minimize potential threats to human health and the environment. The following information provides an overview of the P2 Program, major P2 accomplishments during the reporting year, a comparison of the current year waste generation to prior years, and a description of efforts undertaken during the year to reduce the volume and toxicity of waste generated by the NNSA/NSO.
Date: February 1, 2008
Creator: National Security Technologies, LLC
System: The UNT Digital Library
ANNULUS CLOSURE TECHNOLOGY DEVELOPMENT INSPECTION/SALT DEPOSIT CLEANING MAGNETIC WALL CRAWLER (open access)

ANNULUS CLOSURE TECHNOLOGY DEVELOPMENT INSPECTION/SALT DEPOSIT CLEANING MAGNETIC WALL CRAWLER

The Liquid Waste Technology Development organization is investigating technologies to support closure of radioactive waste tanks at the Savannah River Site (SRS). Tank closure includes removal of the wastes that have propagated to the tank annulus. Although amounts and types of residual waste materials in the annuli of SRS tanks vary, simple salt deposits are predominant on tanks with known leak sites. This task focused on developing and demonstrating a technology to inspect and spot clean salt deposits from the outer primary tank wall located in the annulus of an SRS Type I tank. The Robotics, Remote and Specialty Equipment (RRSE) and Materials Science and Technology (MS&T) Sections of the Savannah River National Laboratory (SRNL) collaborated to modify and equip a Force Institute magnetic wall crawler with the tools necessary to demonstrate the inspection and spot cleaning in a mock-up of a Type I tank annulus. A remote control camera arm and cleaning head were developed, fabricated and mounted on the crawler. The crawler was then tested and demonstrated on a salt simulant also developed in this task. The demonstration showed that the camera is capable of being deployed in all specified locations and provided the views needed for the …
Date: June 1, 2008
Creator: Minichan, R; Russell Eibling, R; James Elder, J; Kevin Kane, K; Daniel Krementz, D; Rodney Vandekamp, R et al.
System: The UNT Digital Library
Apalachicola-Chattahoochee-Flint (ACF) Drought: Federal Water Management Issues (open access)

Apalachicola-Chattahoochee-Flint (ACF) Drought: Federal Water Management Issues

This report provides an introductory analysis of federal water management issues in the Apalachicola-Chattahoochee-Flint (ACF), particularly during drought. The report underscores that decision makers are faced with the tradeoff of the current harm that reduced flows may cause aquatic species against the benefits of maintaining water in storage for future multipurpose use later. The first section briefly introduces the basin's water resources and related federal issues. The second section summarizes current federal reservoir operations. The third section discusses how the municipal, industrial, and agricultural uses of ACF waters affect federal reservoir management. The fourth section covers how species protections affect Corps operations and how Corps operations may affect protected species. The fifth section briefly discusses legislation in the 110th Congress related to the ACF and water supply and management issues in the Southeast. The report concludes with comments about the ACF in the broader context of federal CRS-2 water policies and projects.
Date: May 1, 2008
Creator: Carter, Nicole T.; Kaplan, Stan Mark; Buck, Eugene H.; Brougher, Cynthia & Alexander, Kristina
System: The UNT Digital Library
The application of taylor weighting, digital phase shifters, and digital attenuators to phased-array antennas. (open access)

The application of taylor weighting, digital phase shifters, and digital attenuators to phased-array antennas.

Application of Taylor weighting (taper) to an antenna aperture can achieve low peak sidelobes, but combining the Taylor weighting with quantized attenuators and phase shifters at each radiating element will impact the performance of a phased-array antenna. An examination of array performance is undertaken from the simple point of view of the characteristics of the array factor. Design rules and guidelines for determining the Taylor-weighting parameters, the number of bits required for the digital phase shifter, and the dynamic range and number of bits required for the digital attenuator are developed. For a radar application, when each element is fed directly from a transmit/receive module, the total power radiated by the array will be reduced as a result of the taper. Consequently, the issue of whether to apply the taper on both transmit and receive configurations, or only on the receive configuration is examined with respect to two-way sidelobe performance.
Date: March 1, 2008
Creator: Brock, Billy C.
System: The UNT Digital Library
Application specific compression : final report. (open access)

Application specific compression : final report.

With the continuing development of more capable data gathering sensors, comes an increased demand on the bandwidth for transmitting larger quantities of data. To help counteract that trend, a study was undertaken to determine appropriate lossy data compression strategies for minimizing their impact on target detection and characterization. The survey of current compression techniques led us to the conclusion that wavelet compression was well suited for this purpose. Wavelet analysis essentially applies a low-pass and high-pass filter to the data, converting the data into the related coefficients that maintain spatial information as well as frequency information. Wavelet compression is achieved by zeroing the coefficients that pertain to the noise in the signal, i.e. the high frequency, low amplitude portion. This approach is well suited for our goal because it reduces the noise in the signal with only minimal impact on the larger, lower frequency target signatures. The resulting coefficients can then be encoded using lossless techniques with higher compression levels because of the lower entropy and significant number of zeros. No significant signal degradation or difficulties in target characterization or detection were observed or measured when wavelet compression was applied to simulated and real data, even when over 80% of …
Date: December 1, 2008
Creator: Melgaard, David Kennett; Byrne, Raymond Harry; Myers, Daniel S.; Harrison, Carol D.; Lee, David S.; Lewis, Phillip J. et al.
System: The UNT Digital Library