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Partition of solutes from the gas phase and from water to wet and dry di-n-butyl ether: a linear free energy relationship analysis

Description: Article on the partition of solutes from the gas phase and from water to wet and dry di-n-butyl ether and a linear free energy relationship analysis.
Date: August 13, 2001
Creator: Abraham, M. H. (Michael H.); Zissimos, Andreas M. & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences
open access

Wear and friction behavior of Zr implanted D3 steel

Description: Multicharged, pure, high current and pulsed ion beams of Zr have been extracted from a metal vapor vacuum arc (MEVVA) source and implanted into AISI D3 (C: 2-2,35%, Mn: 0,60%, Si: 0,60%, Cr: 11-13,50%, Ni: 0,30%, W: 1%, V: 1%) tool steel samples at the 3,6.1016, 5.1016 and 1.1017 ions/cm2 doses. The wear resistance and friction coefficient have been estimated using pin-on-disc wear tests. Implantation of Zr decreased the wear loss and friction coefficient. RBS, AES and SEM Microprobe analyses were used as a guide for explanation of implantation's effects.
Date: August 23, 2001
Creator: Akbas, N.; Saklakoglu, I.E.; Monteiro, O.R. & Brown, I.G.
Partner: UNT Libraries Government Documents Department
open access

Problems Encountered in Money Laundering Investigations

Description: The purpose of this study is to identify how the U.S. is responding to money laundering and what kind of problems arise while countering it, beginning with a detailed description of money laundering, its stages, typologies, impacts, and complications. Due to the broad nature of this subject only three main issues form the focal point of this study: problems concerning the banking industry and other financial organizations, problems resulting from the limitations of law enforcement agencies, and problems arising from the lack of cooperation between and within financial institutions and law enforcement agencies. Several probable solutions to the above problems are identified: Considering the financial industry, there are loopholes in the Bank Secrecy Act (BSA) and in other regulations that apply to the industry. Thus, there is a comparison of the Subjective Model vs. Objective Model in terms of reporting systems for financial organizations. On the law enforcement side, the priority is the need to update and upgrade their technology and investigation mechanisms in order not to fall behind the criminals. Finally, cooperation is something that can be achieved through mutual respect and understanding of the priorities of each side, which can be achieved by the creation of an upper agency of whose members represent both sides of the combat efforts.
Date: August 2001
Creator: Akyay, Ilkay
Partner: UNT Libraries
open access

Investigation of Mixed Metal Sorbent/Catalysts for the Simultaneous Removal of Sulfur and Nitrogen Oxides

Description: Simultaneous removal of SO{sub 2} and NO{sub x} using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO{sub 2} and NO{sub x} removal operations. The work done at PETC and the DOE-funded investigation of the investigators on the sulfation and regeneration of alumina-supported cerium oxide sorbents have shown that they can perform well at relatively high temperatures (823-900 K) as regenerable desulfurization sorbents. Survey of the recent literature shows that addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K, sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures, SO{sub 2} can be directly reduced to sulfur by CO on CuO-ceria catalysts, and ceria-based catalysts may have a potential for selective catalytic reduction of NO{sub x} by methane. These observations indicate a possibility of developing a ceria-based sorbent/catalyst which can remove both SO{sub 2} and NO{sub x} from flue gases within a relatively wide temperature window, produce significant amounts of elemental sulfur during regeneration, and use methane for the selective catalytic reduction of NO{sub x}.
Date: August 1, 2001
Creator: Akyurtlu, Ates & Akyurtle, Jale F.
Partner: UNT Libraries Government Documents Department
open access

Computer Modeling of Saltstone Landfills by Intera Environmental Consultants

Description: This report summaries the computer modeling studies and how the results of these studies were used to estimate contaminant releases to the groundwater. These modeling studies were used to improve saltstone landfill designs and are the basis for the current reference design. With the reference landfill design, EPA Drinking Water Standards can be met for all chemicals and radionuclides contained in Savannah River Plant waste salts.
Date: August 9, 2001
Creator: Albenesius, E.L.
Partner: UNT Libraries Government Documents Department

Oral History Interview with Richard E. Cole, August 8, 2000

Description: Interview with Army Air Forces veteran Richard E. Cole. The interview includes Cole's personal experiences about being Jimmy Doolittle's co-pilot during the Tokyo Raid on April 8, 1942, pre-war education, flight training, volunteering for a secret mission and meeting Colonel Doolittle, being assigned as Doolittle's co-pilot, mission training, various B-25 missions against Japanese targets in China and Burma, flying supplies over "The Hump." transferring to the states and volunteering for service in Burma with the 1st Air Commandos to support Wingate's Chindits and Merrill's Marauders, and reunions of Doolittle's Raiders the following war.
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 8, 2001
Creator: Alexander, William J. & Cole, Richard E.
Partner: UNT Oral History Program
open access

Assessing Risk of Innovation

Description: Today's manufacturing systems and equipment must perform at levels thought impossible a decade ago. Companies must push operations, quality, and efficiencies to unprecedented levels while holding down costs. In this new economy, companies must be concerned with market shares, equity growth, market saturation, and profit. U.S. manufacturing is no exception and is a prime example of businesses forced to adapt to constant and rapid changes in customer needs and product mixes, giving rise to the term ''Agile Manufacturing''. The survival and ultimate success of the American Manufacturing economy may depend upon its ability to create, innovate, and quickly assess the impact that new innovations will have on its business practices. Given the need for flexibility, companies need proven methods to predict and measure the impact that new technologies and strategies will have on overall plant performance from an enterprise perspective. The Value-Derivative Model provides a methodology and approach to assess such impacts in terms of energy savings, production increases, quality impacts, emission reduction, and maintenance and operating costs as they relate to enabling and emerging technologies. This is realized by calculating a set of first order sensitivity parameters obtained from expanding a Taylor Series about the system's operating point. These sensitivity parameters are invariant economic and operational indicators that quantify the impact of any proposed technology in terms of material throughput, efficiency, energy usage, environmental effects, and costs. These parameters also provide a mechanism to define metrics and performance measures that can be qualified in terms of real economic impact. Value-Derivative Analysis can be applied across all manufacturing and production segments of our economy and has found specific use in steel and textiles. Where economic models give the cost of conducting a business, Value-Derivative Analysis provides the cost to conduct business . Benefits derived from conducting a Value-Derivative Analysis include: …
Date: August 15, 2001
Creator: Allgood, GO
Partner: UNT Libraries Government Documents Department
open access

LED-induced fluorescence diagnostics for turbine and combustion engine thermometry

Description: Fluorescence from phosphor coatings is the basis of an established technique for measuring temperature in a wide variety of turbine and combustion engine applications. Example surfaces include blades, vanes, combustors, intake valves, pistons, and rotors. Many situations that are remote and noncontact require the high intensity of a laser to illuminate the phosphor, especially if the surface is moving. Thermometric resolutions of 0.1 C are obtainable, and some laboratory versions of these systems have been calibrated against NIST standards to even higher precision. To improve the measurement signal-to-noise ratio, synchronous detection timing has been used to repeatedly interrogate the same blade in a high speed rotating turbine. High spatial resolution can be obtained by tightly focusing the interrogation beam in measurements of static surfaces, and by precise differential timing of the laser pulses on rotating surfaces. We report here the use of blue light emitting diodes (LEDs) as a n illumination source for producing useable fluorescence from phosphors for temperature measurements. An LED can excite most of the same phosphors used to cover the temperature range from 8 to 1400 C. The advantages of using LEDs are obvious in terms of size, power requirements, space requirements and cost. There can also be advantages associated with very long operating lifetimes, wide range of available colors, and their broader emission bandwidths as compared to laser diodes. Temperature may be inferred either from phase or time-decay determinations.
Date: August 17, 2001
Creator: Allison, S. W.
Partner: UNT Libraries Government Documents Department
open access

Reducing ion beam noise of vacuum arc ion sources

Description: Vacuum arc ion sources are known for delivering high currents of metal ion beams. By Langmuir probe and Faraday cup measurements it is shown that fluctuations of the ion beam current are due to the fluctuations of plasma density which in turn are due to the explosive nature of plasma production at cathode spots. Humphries and co-workers and later Oks and co-workers have shown that beam fluctuations can be reduced by inserting biased meshes in the plasma. Here, the idea of ion extraction at kV-level with post-acceleration is investigated. The high voltage allows us to use coarse, ridged meshes or grids. The combination of an extractor operating in the overdense plasma regime with post-acceleration lead to very reproducible, practically ''noiseless'' ion beams however at the expense of low ion current density. The noise reduction is due to ion optics effects. Although the current setup is not suitable for a heavy ion fusion injector due to the low beam current and the risk of extractor voltage breakdown, further development of the concept may lead to reproducible beam pulses of sufficiently high current and brightness.
Date: August 29, 2001
Creator: Anders, Andre & Hollinger, Ralph
Partner: UNT Libraries Government Documents Department

A Comparison of Five Robust Regression Methods with Ordinary Least Squares: Relative Efficiency, Bias and Test of the Null Hypothesis

Description: A Monte Carlo simulation was used to generate data for a comparison of five robust regression estimation methods with ordinary least squares (OLS) under 36 different outlier data configurations. Two of the robust estimators, Least Absolute Value (LAV) estimation and MM estimation, are commercially available. Three authormodified variations on MM were also included (MM1, MM2, and MM3). Design parameters that were varied include sample size (n=60 and n=180), number of independent predictor variables (2, 3 and 6), outlier density (0%, 5% and 15%) and outlier location (2x,2y s, 8x8y s, 4x,8y s and 8x,4y s). Criteria on which the regression methods were measured are relative efficiency, bias and a test of the null hypothesis. Results indicated that MM2 was the best performing robust estimator on relative efficiency. The best performing estimator on bias was MM1. The best performing regression method on the test of the null hypothesis was MM2. Overall, the MM-type robust regression methods outperformed OLS and LAV on relative efficiency, bias, and the test of the null hypothesis.
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2001
Creator: Anderson, Cynthia, 1962-
Partner: UNT Libraries
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John Graves and the Pastoral Tradition

Description: John Graves's creative non-fiction has earned him respect in Texas letters as a seminal writer but scarce critical commentary of his work outside the region. Ecological criticism examines how language, culture and the land interact, providing a context in which to discuss Graves in relation to the southwestern literary tradition of J. Frank Dobie, Walter P. Webb, and Roy Bedichek, to southern pastoral in the Virgilian mode, and to American nature writing. Graves's rhetorical strategies, including his appropriation of form, his non-polemical voice, his experimentation with narrative persona, and his utilization of traditional tropes of metaphor, metonymy, and irony, establish him as a conservative and Romantic writer of place concerned with the friction between traditional agrarian values and the demands of late-twentieth-century urban/technological existence. Sequentially, Graves's three main booksGoodbye to a River (1960), Hard Scrabble (1974), and From a Limestone Ledge (1980)represent a movement from the pastoral mode of the outward journey and return to the more domestic world of georgic, from the mode of leisure and contemplation to the demands and rewards of hard work and ownership. As such they represent not only progression or maturation in the arc of the narrator's life but a desire to reconcile ideological poles first examined so long ago in Virgil: leisure and work, freedom and responsibility, rural and urban values.
Date: August 2001
Creator: Anderson, David Roy
Partner: UNT Libraries

Barriers Limiting Access to Hospice Care for Elderly African Americans in Amarillo, Texas

Description: This study examines barriers limiting access to hospice care for elderly African Americans. Ethnic background plays a critical role in the development of attitudes, beliefs and expectations related to death and issues surrounding hospice care. The purpose of this study was to identify barriers that may limit access to hospice care for African Americans. A questionnaire was administered to 56 elderly African Americans in three religious settings and an African American senior citizens center. The questionnaire was designed to obtain information concerning African Americans' attitudes toward death and dying; religious beliefs; health beliefs; familiarity with hospice and prospective use of hospice. The results of the study indicate a number of barriers in access to hospice care for African Americans including: hospice knowledge barriers; education/outreach barriers; cultural knowledge barriers related to death/dying values; family/social support barriers; hospice organizational/provider barriers; health care organizational/provider barriers; and reimbursement barriers.
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2001
Creator: Anthony, Tomagene
Partner: UNT Libraries
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Revisiting Eric Nordlinger: The Dynamics of Russian Civil- Military Relations in the Twentieth Century

Description: This paper examines the role that military has played in the political development of the former Union of Soviet Socialist Republics and the modern Russian Federation. By utilizing the theoretical tenets of Eric Nordlinger, this paper endeavors to update and hopefully revise his classic work in civil-military relations, Soldiers in Politics. Chapter one of this paper introduces many of the main theoretical concepts utilized in this analysis. Chapter two considers the Stalinist totalitarian penetration model that set the standard for communist governments around the world. Chapter three follows up by addressing the middle years of Khrushchev and Brezhnev. Both reformed the military in its relation to the party and state and made the armed forces a more corporate and professional institution. Chapter four pinpoints the drastic changes in both the state and armed forces during Gorbachev's perestroika and glasnost. The military briefly ventured to a point it never gone before by launching a short coup against the last Soviet president. Chapter five focuses on the last ten years in the Russian Federation. While still a professional organization typical of the liberal model of civil-military relations, the armed forces face great uncertainty, as economic and social problems demand more of their time and resources. Chapter six concludes by speculating on the future of Russian civilmilitary relations and reconsiders the importance of Nordlinger's elegant yet parsimonious work.
Date: August 2001
Creator: Ardovino, Michael
Partner: UNT Libraries
open access

The relationship between models of student laptop computer use and teacher instructional behavior

Description: This study investigated the relationship between four models of student laptop computer use and three components of teacher instructional behavior: planning, implementation of instruction, and evaluation of instruction. The four models of use: full access, dispersed, class set, and mixed, represented the numerous ways teachers in public and private schools and school districts nationwide implemented student use of laptop computers. Teacher planning behavior was investigated with regard to time, frequency, complexity, difficulty, the need for revision, and use of technological resources and materials. Implementation of instruction was examined with regard to student grouping, instructional strategies, instructional content/subject matter, teacher and student roles, assignments and learning tasks, and instructional activities. The evaluation of instruction component was examined with regard to assessment tasks, grading, and assessment of homework. Using a researcher-designed questionnaire, data was gathered in a single-stage cross-sectional survey from 356 teachers working in 74 public and private schools nationwide. Results indicated models of student laptop computer use had differential effects on teacher instructional behaviors. On average, teachers found planning to be more arduous, but more collegial, especially in the mixed model. The full access and mixed models were more likely to advance a constructivist approach to teacher instructional behaviors with regard to implementation and evaluation of instruction. Results from this study had implications for future research. The effects of student laptop computer use on the full access and mixed models of use should be given further study with regard to the implementation and evaluation of instruction.
Date: August 2001
Creator: Ashmore, Barbara A.
Partner: UNT Libraries
open access

Atrazine Monitoring and Modeling in the Lake Lavon Watershed

Description: This report describes a study to identify the distribution and extent of areas potentially at risk for atrazine (a broad leaf weedkiller) runoff in the Lake Lavon watershed, which is a major water supply for the Dallas area. The report presents the results of the study and makes recommendations for how information can be used in a cost-effective watershed atrazine reduction strategy.
Date: August 2001
Creator: Atkinson, Samuel F.; Waller, William T.; Dickson, Kenneth L.; Sanmanee, Sirichai & Moreno, Maria C.
Partner: UNT Libraries
open access

Ion Temperature Measurements in SSPX

Description: The Ion Doppler Spectrometer instrument on the Sustained Spheromak Physics experiment is described, along with background about it's operation. Results are presented from recent experimental runs, and the data is compared to the results of simple statistical models of heat exchange in two species gasses.
Date: August 24, 2001
Creator: Auerbach, D W; Hill, D N & McLean, H S
Partner: UNT Libraries Government Documents Department
open access

Analysis of Fabry-Perot Velocimeter Records

Description: Program demonstration and user instructions are presented for FabryVB5. This computer program was created for use in analyzing Fabry-Perot interferometer records that detail the velocity time histories of fast moving surfaces. Graphical curves representing peak fringe positions and fiducial timing dots are extracted from a digitized film record or from a CCD digital image. An analysis is demonstrated on a sample velocimeter record along with some mathematical formula and routine operations. Routines used to analyze calibration records on streak camera distortions are illustrated in an appendix. This is a Microsoft Visual Basic{trademark} version for the PC.
Date: August 3, 2001
Creator: Avara, G.
Partner: UNT Libraries Government Documents Department
open access

ADVANCED DATA PROCESSING FOR VOLUMETRIC COMPUTED TOMOGRAPHY DATA

Description: Computed tomography (CT) has long been used by industry as a non-destructive evaluation technique for discovering flaws in parts before their use. Traditional linear array computed tomography systems acquired data at a rate that could be reconstructed simultaneously with data acquisition. With new area detectors, the data rate of acquisition has increased exponentially, and the reconstruction algorithm does not scale linearly with increased data. FlashCT DPS (Flat Panel Amorphous Silicon High Resolution Computed Tomography, Data Processing System) is a software package developed by M. Sheats, and A. Davis at LANL to meet the data processing demands of new flat panel array computed tomography. FlashCT--DPS combines several features unique to industrial computed tomography systems. It addresses traditional usability problems by providing an intuitive graphical user interface and powerful analysis tools. It includes the three major CT reconstruction algorithms: parallel backprojection, fan beam resorting, and Feldkamp cone beam. It also provides visualization tools for examination of data after processing. Finally, it is able to perform distributed data reconstruction with a near linear speed increase as a function of the number of processors used. Additionally, utility programs have been developed to support project editing and computing cluster management for the FlashCT system. FlashCT--DPS runs on a standard PC platform and operates well on a variety of processor and memory configurations.
Date: August 1, 2001
Creator: BERKELEY, M. SHEATS - UC
Partner: UNT Libraries Government Documents Department
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