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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.
Object Type:
Report
System:
The UNT Digital Library
Analysis of Thermally Induced Changes in Fractured Rock Permeability during Eight Years of Heating and Cooling at the Yucca Mountain Drift Scale Test
We analyzed a data set of thermally induced changes in fractured rock permeability during a four-year heating (up to 200 C) and subsequent four-year cooling of a large volume, partially saturated and highly fractured volcanic tuff at the Yucca Mountain Drift Scale Test, in Nevada, USA. Permeability estimates were derived from about 700 pneumatic (air-injection) tests, taken periodically at 44 packed-off borehole intervals during the heating and cooling cycle from November 1997 through November 2005. We analyzed air-permeability data by numerical modeling of thermally induced stress and moisture movements and their impact on air permeability within the highly fractured rock. Our analysis shows that changes in air permeability during the initial four-year heating period, which were limited to about one order of magnitude, were caused by the combined effects of thermal-mechanically-induced stress on fracture aperture and thermal-hydrologically-induced changes in fracture moisture content. At the end of the subsequent four-year cooling period, air-permeability decreases (to as low as 0.2 of initial) and increases (to as high as 1.8 of initial) were observed. By comparison to the calculated thermo-hydro-elastic model results, we identified these remaining increases or decreases in air permeability as irreversible changes in intrinsic fracture permeability, consistent with either inelastic …
Date:
June 1, 2008
Creator:
Rutqvist, J.; Freifeld, B.; Min, K.-B.; Elsworth, D. & Tsang, Y.
Object Type:
Article
System:
The UNT Digital Library
Analysis of voltage spikes in superconducting Nb3Sn magnets
Fermi National Accelerator Laboratory has been developing a new generation of superconducting accelerator magnets based on Niobium Tin (Nb{sub 3}Sn). The performance of these magnets is influenced by thermo-magnetic instabilities, known as flux jumps, which can lead to premature trips of the quench detection system due to large voltage transients or quenches at low current. In an effort to better characterize and understand these instabilities, a system for capturing fast voltage transients was developed and used in recent tests of R&D model magnets. A new automated voltage spike analysis program was developed for the analysis of large amount of voltage-spike data. We report results from the analysis of large statistics data samples for short model magnets that were constructed using MJR and RRP strands having different sub-element size and structure. We then assess the implications for quench protection of Nb{sub 3}Sn magnets.
Date:
August 1, 2008
Creator:
Rahimzadeh-Kalaleh, S.; Ambrosio, G.; Chlachidze, G.; Donnelly, C. & Tartaglia, M.
Object Type:
Article
System:
The UNT Digital Library
Analysis of X-Ray Spectra Emitted From the Venus ECR Ion Source
The Versatile Electron Cyclotron resonance ion source for Nuclear Science (VENUS), located at Lawrence Berkeley National Lab’s 88-inch cyclotron, extracts ion beams from a plasma created by ionizing a gas with energetic electrons. Liquid-helium cooled superconducting coils produce magnetic fi elds that confi ne the plasma and high microwave frequencies heat the electrons enough to allow for successive ionizations of the neutral gas atoms. The combination of strong plasma confi nement and high microwave frequencies results in VENUS’ production of record breaking ion beam currents and high charge state distributions. While in operation, VENUS produces signifi cant quantities of bremsstrahlung, in the form of x-rays, primarily through two processes: 1) electron-ion collisions within the plasma, and 2) electrons are lost from the plasma, collide with the plasma chamber wall, and radiate bremsstrahlung due to their sudden deceleration. The bremsstrahlung deposited into the plasma chamber wall is absorbed by the cold mass used to maintain superconductivity in the magnets and poses an additional heat load on the cryostat. In order for VENUS to reach its maximum operating potential of 10 kW of 28 GHz microwave heating frequency, the heat load posed by the emitted bremsstrahlung must be understood. In addition, studying …
Date:
January 1, 2008
Creator:
Benitez, J. & Leitner, D.
Object Type:
Article
System:
The UNT Digital Library
Analysis on the Density Driven Air-Ingress Accident in VHTRs
Air-ingress following the pipe rupture is considered to be the most serious accident in the VHTRs due to its potential problems such as core heat-up, structural integrity and toxic gas release. Previously, it has been believed that the main air-ingress mechanism of this accident is the molecular diffusion process between the reactor core and the cavity. However, according to some recent studies, there is another fast air-ingress process that has not been considered before. It is called density-driven stratified flow. The potential for density-driven stratified air ingress into the VHTR following a large-break LOCA was first described in the NGNP Methods Technical Program based on stratified flow studies performed with liquid. Studies on densitygradient driven stratified flow in advanced reactor systems has been the subject of active research for well over a decade since density-gradient dominated stratified flow is an inherent characteristic of passive systems used in advanced reactors. Recently, Oh et al. performed a CFD analysis on the stratified flow in the VHTR, and showed that this effect can significantly accelerate the air-ingress process in the VHTRs. They also proposed to replace the original air-ingress scenario based on the molecular diffusion with the one based on the stratified flow. …
Date:
November 1, 2008
Creator:
Kim, Eung Soo; Oh, Chang; Schultz, Richard & Petti, David
Object Type:
Article
System:
The UNT Digital Library
An analysis on the mid-latitude scintillation and coherence frequency bandwidth using transionospheric VHF signals
An analysis was perfonned on the mid-latitude scintillation and coherence frequency bandwidth (Fcoh) using transionospheric VHF signal data. The data include 1062 events spanning from November 1997 to June 2002. Each event records FORTE satellite received VHF signals from LAPP located at Los Alamos, New Mexico. Fcohs were derived to study scintillation characteristics on diurnal and seasonal variations, as well as changes due to solar and geomagnetic activities. Comparisons to the VHFIUHF coherence frequency bandwidth studies previously reported at equatorial and mid-latitude regions are made using a 4th power frequency dependence relationship. Furthennore, a wideband ionospheric scintillation model, WBMOD, was used to estimate Fcohs and compared with our VHF Fcoh values. Our analysis indicates mid-latitude scintillation characteristics that are not previously revealed. At the VHF bottom frequency range (3035 MHz), distinguished smaller Fcohs are found in time period from sunset to midnight, in wann season from May to August, and in low solar activity years. The effects of geomagnetic storm activity on Fcoh are characterized by a sudden transition at a Kp index of 50-60. Comparisons with median Fcohs estimated from other studies validated our VHF Fcohs for daytime while an order of magnitude larger Fcohs are found for nighttime, …
Date:
January 1, 2008
Creator:
Juang, Zhen & Roussel-dupre, Robert
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
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
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.
Object Type:
Report
System:
The UNT Digital Library
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.
Object Type:
Report
System:
The UNT Digital Library
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
Object Type:
Report
System:
The UNT Digital Library
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
Object Type:
Report
System:
The UNT Digital Library
Anisotropic Hexagonal Boron Nitride Nanomaterials - Synthesis and Applications
Boron nitride (BN) is a synthetic binary compound located between III and V group elements in the Periodic Table. However, its properties, in terms of polymorphism and mechanical characteristics, are rather close to those of carbon compared with other III-V compounds, such as gallium nitride. BN crystallizes into a layered or a tetrahedrally linked structure, like those of graphite and diamond, respectively, depending on the conditions of its preparation, especially the pressure applied. Such correspondence between BN and carbon readily can be understood from their isoelectronic structures [1, 2]. On the other hand, in contrast to graphite, layered BN is transparent and is an insulator. This material has attracted great interest because, similar to carbon, it exists in various polymorphic forms exhibiting very different properties; however, these forms do not correspond strictly to those of carbon. Crystallographically, BN is classified into four polymorphic forms: Hexagonal BN (h-BN) (Figure 1(b)); rhombohedral BN (r-BN); cubic BN (c-BN); and wurtzite BN (w-BN). BN does not occur in nature. In 1842, Balmain [3] obtained BN as a reaction product between molten boric oxide and potassium cyanide under atmospheric pressure. Thereafter, many methods for its synthesis were reported. h-BN and r-BN are formed under ambient …
Date:
August 1, 2008
Creator:
Han,W.Q.
Object Type:
Book
System:
The UNT Digital Library
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.
Object Type:
Report
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
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
Object Type:
Report
System:
The UNT Digital Library
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
Object Type:
Report
System:
The UNT Digital Library
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.
Object Type:
Report
System:
The UNT Digital Library
Anomalous yield reduction in direct-drive DT implosions due to 3He addition
Glass capsules were imploded in direct drive on the OMEGA laser [T. R. Boehly et aI., Opt. Commun. 133, 495, 1997] to look for anomalous degradation in deuterium/tritium (DT) yield (i.e., beyond what is predicted) and changes in reaction history with {sup 3}He addition. Such anomalies have previously been reported for D/{sup 3}He plasmas, but had not yet been investigated for DT/{sup 3}He. Anomalies such as these provide fertile ground for furthering our physics understanding of ICF implosions and capsule performance. A relatively short laser pulse (600 ps) was used to provide some degree of temporal separation between shock and compression yield components for analysis. Anomalous degradation in the compression component of yield was observed, consistent with the 'factor of two' degradation previously reported by MIT at a 50% {sup 3}He atom fraction in D{sub 2} using plastic capsules [Rygg et aI., Phys. Plasmas 13, 052702 (2006)]. However, clean calculations (i.e., no fuel-shell mixing) predict the shock component of yield quite well, contrary to the result reported by MIT, but consistent with LANL results in D{sub 2}/{sup 3}He [Wilson, et aI., lml Phys: Conf Series 112, 022015 (2008)]. X-ray imaging suggests less-than-predicted compression ofcapsules containing {sup 3}He. Leading candidate explanations …
Date:
January 1, 2008
Creator:
Herrmann, Hans W.; Langenbrunner, James R.; Mack, Joseph M.; Cooley, James H.; Wilson, Douglas C.; Evans, Scott C. et al.
Object Type:
Article
System:
The UNT Digital Library
The Anti-B ---> D* l anti-nu form factor at zero recoil from three-flavor lattice QCD: A Model independent determination of |V(cb)|
None
Date:
August 1, 2008
Creator:
Bernard, C.; DeTar, C.; Di Pierro, M.; El-Khadra, A. X.; Evans, R. T.; Freeland, E. D. et al.
Object Type:
Article
System:
The UNT Digital Library
t anti-t production cross section measurement using soft electron tagging in p anti-p collisions at s**(1/2) = 1.96-TeV
We measure the production cross section of t{bar t} events in p{bar p} collisions at {radical}s = 1.96 TeV. The data was collected by the CDF experiment in Run 2 of the Tevatron accelerator at the Fermi National Accelerator Laboratory between 2002 and 2007. 1.7 fb{sup -1} of data was recorded during this time period. We reconstruct t{bar t} events in the lepton+jets channel, whereby one W boson - resulting from the decay of the top quark pairs - decays leptonically and the other hadronically. The dominant background to this process is the production of W bosons in association with multiple jets. To distinguish t{bar t} from background, we identify soft electrons from the semileptonic decay of heavy flavor jets produced in t{bar t} events. We measure a cross section of {sigma}{sub p{bar p}} = 7.8 {+-} 2.4(stat) {+-} 1.6(syst) {+-} 0.5(lumi).
Date:
September 1, 2008
Creator:
Chou, John Paul & U., /Harvard
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
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
Object Type:
Report
System:
The UNT Digital Library
Applicability of a Bonner Shere technique for pulsed neutron in 120 GeV proton facility
The data on neutron spectra and intensity behind shielding are important for radiation safety design of high-energy accelerators since neutrons are capable of penetrating thick shielding and activating materials. Corresponding particle transport codes--that involve physics models of neutron and other particle production, transportation, and interaction--have been developed and used world-wide [1-8]. The results of these codes have been ensured through plenty of comparisons with experimental results taken in simple geometries. For neutron generation and transport, several related experiments have been performed to measure neutron spectra, attenuation length and reaction rates behind shielding walls of various thicknesses and materials in energy range up to several hundred of MeV [9-11]. The data have been used to benchmark--and modify if needed--the simulation modes and parameters in the codes, as well as the reference data for radiation safety design. To obtain such kind of data above several hundred of MeV, Japan-Fermi National Accelerator Laboratory (FNAL) collaboration for shielding experiments has been started in 2007, based on suggestion from the specialist meeting of shielding, Shielding Aspects of Target, Irradiation Facilities (SATIF), because of very limited data available in high-energy region (see, for example, [12]). As a part of this shielding experiment, a set of Bonner …
Date:
February 1, 2008
Creator:
Sanami, T.; Hagiwara, M.; Iwase, H.; Iwamoto, Y.; Sakamoto, Y.; Nakashima, H. et al.
Object Type:
Article
System:
The UNT Digital Library
Application of Gamma code coupled with turbomachinery models for high temperature gas-cooled reactors
The very high-temperature gas-cooled reactor (VHTR) is envisioned as a single- or dual-purpose reactor for electricity and hydrogen generation. The concept has average coolant temperatures above 9000C and operational fuel temperatures above 12500C. The concept provides the potential for increased energy conversion efficiency and for high-temperature process heat application in addition to power generation. While all the High Temperature Gas Cooled Reactor (HTGR) concepts have sufficiently high temperature to support process heat applications, such as coal gasification, desalination or cogenerative processes, the VHTR’s higher temperatures allow broader applications, including thermochemical hydrogen production. However, the very high temperatures of this reactor concept can be detrimental to safety if a loss-ofcoolant accident (LOCA) occurs. Following the loss of coolant through the break and coolant depressurization, air will enter the core through the break by molecular diffusion and ultimately by natural convection, leading to oxidation of the in-core graphite structure and fuel. The oxidation will accelerate heatup of the reactor core and the release of a toxic gas, CO, and fission products. Thus, without any effective countermeasures, a pipe break may lead to significant fuel damage and fission product release. Prior to the start of this Korean/United States collaboration, no computer codes were …
Date:
February 1, 2008
Creator:
Oh, Chang
Object Type:
Article
System:
The UNT Digital Library
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.
Object Type:
Report
System:
The UNT Digital Library
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.
Object Type:
Report
System:
The UNT Digital Library