Color Transparency and the Energy Evolution of Final-State Interactions in Charmonium Photoproduction (open access)

Color Transparency and the Energy Evolution of Final-State Interactions in Charmonium Photoproduction

None
Date: January 1, 1991
Creator: Gardner, A. & Gardner, Susan
Object Type: Report
System: The UNT Digital Library
Generalized emittance measurements in a beam transport line (open access)

Generalized emittance measurements in a beam transport line

Motivated by the need to commission 3 beam transport lines for the new AGS Booster project, we have developed a generalized emittance-measurement program; beam line specifics are entirely resident in data tables, not in program code. For instrumentation, the program requires one or more multi-wire profile monitors; one or multiple profiles are acquired from each monitor, corresponding to one or multiple tunes of the transport line. Emittances and Twiss parameters are calculated using generalized algorithms. The required matix descriptions of the beam optics are constructed by an on-line general beam modeling program. Design of the program, its algorithms, and initial experience with it will be described. 4 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Skelly, J.; Gardner, C.; Luccio, A.; Kponou, A. & Reece, K.
Object Type: Article
System: The UNT Digital Library
Indium dopant/defect complexes in lightly-doped ceria (open access)

Indium dopant/defect complexes in lightly-doped ceria

Four well-defined indium-dopant/lattice-defect complexes and the non-complexed substitutional indium dopant have been observed by perturbed angular correlation (PAC) spectroscopy in cerium oxide. PAC is a nuclear hyperfine experimental method that detects interactions between a radioactive probe nucleus and nearby atoms. The magnitude and symmetry of those interactions provide a signature for the electromagnetic fields at the probe nucleus. These fields are produced by the arrangement of charges and magnetic moments in the near environment of the probe, so they provide a means of identifying defect structures.
Date: January 1, 1991
Creator: Wang, Ruiping; Gardner, J.A. (Oregon State Univ., Corvallis, OR (United States). Dept. of Physics); Evenson, W.E. (Brigham Young Univ., Provo, UT (United States). Dept. of Physics) & Sommers, J.A. (Teledyne-Wah Chang, Albany, OR (United States))
Object Type: Article
System: The UNT Digital Library
PAC spectroscopy of electronic ceramics (open access)

PAC spectroscopy of electronic ceramics

Dilute indium dopants in cerium oxides and YBa{sub 2}Cu{sub 3}O{sub x} have been studied by{sup 111}In/Cd Perturbed Angular Correlation (PAC) spectroscopy. By controlling oxygen vacancy concentration in the cerium oxides through doping or high-temperature vacuum annealing, we have found that indium always forms a defect complex unless the sample is doped to reduce greatly the oxygen vacancy concentration. Three different vacancy-associated complexes are found with concentrations that depend on doping and oxygen stoichiometry. Another defect complex occurs in samples having negligible vacancy concentration. At low temperatures, evidence is found of interaction with an electronic hole trapped by {sup 111}Cd after the radioactive decay of the {sup 111}In parent. In YBa{sub 2}Cu{sub 3}O{sub x} the indium substitutes preferentially at the Y site but has measurable probability of substitution in at least one of the two copper sites. A symmetry change near 650 {degree}C is consistent with the well-documented orthorhombic/tetragonal transition for samples in air or oxygen.
Date: January 1, 1991
Creator: Gardner, J.A.; Wang, Ruiping; Schwenker, R. (Oregon Univ., Eugene, OR (United States). Dept. of Physics); Evenson, W.E. (Brigham Young Univ., Provo, UT (United States). Dept. of Physics and Astronomy); Rasera, R.L. (Maryland Univ., Catonsville, MD (United States). Dept. of Physics) & Sommers, J.A. (Teledyne-Wah Chang, Albany, OR (United States))
Object Type: Report
System: The UNT Digital Library
Three-dimensional calculations of fields and loading for loop and folded waveguide ICRF antennas (open access)

Three-dimensional calculations of fields and loading for loop and folded waveguide ICRF antennas

The ANT and ORION codes have been combined and used to study the loading of various antenna geometries with simple three-dimensional (3-D) effects. Both codes use a slab model with periodic Fourier analysis for modeling the toroidal and poloidal directions. The ANT code is used to prescribe current sets in a vacuum region where the field solutions are obtained analytically of each Fourier mode and matching conditions are used at poloidal/toroidal current sheet locations. Multiple current sheets are permitted and various feeder options are available to model the radial antenna currents. Current elements maybe oriented at arbitrary angles to the static magnetic field and may be independently phased in time. The fields at the plasma surface are prescribed by an impedance matrix for each Fourier mode. The ORION code solves for the fields in the plasma region using finite difference techniques, a plasma dispersion relation that retains the lowest-order finite gyroradius effects, and all three electric field components. Results are presented for a folded waveguide mock-up and for a loop antenna design under identical plasma conditions.
Date: January 1, 1991
Creator: Carter, M. D.; Baity, F. W.; Batchelor, D. B.; Hoffman, D. J.; Jaeger, E. F.; Swain, D. W. et al.
Object Type: Article
System: The UNT Digital Library
On preferential flow and its measurement (open access)

On preferential flow and its measurement

Preferential flow is a useful generic term for describing the process whereby water movement through a porous medium follows favored routes bypassing other parts of the medium. This term does not give any indication of the pore scales involved. Sometimes macropore flow is used to describe preferential flow and this term implies that large pores of some sort are conductive. There is no consensus definition of what constitutes a macropore so one needs to carefully determine what is meant when that term is used. The main focus of this report is on the measurement and characterization of preferential flow through structured soils, however, preferred path flow also occurs in sandy soils. Fingering flow in soils, a result of wetting front instability, is a third type of preferential flow that occurs in porous media with more or less random pore arrangement. There may not be any physically defined channels in the soil to account for this type of flow. A larger scale flow described as funnel flow by Kung et al. (1990) results from profile heterogeneity. Low permeability layers or coarse lenses in a profile may restrict vertical drainage redirecting flow laterally through specific regions of the profile (like a funnel). …
Date: January 1, 1991
Creator: Luxmoore, R. J.
Object Type: Article
System: The UNT Digital Library
The oncogenic action of ionizing radiation on rat skin (open access)

The oncogenic action of ionizing radiation on rat skin

Progress has occurred in several areas corresponding to the specific aims of the proposal: (1) Progression and multiple events in radiation carcinogenesis of rat skin as a function of LET; (2) cell cycle kinetics of irradiated rat epidermis as determined by double labeling and double emulsion autoradiography; (3) oncogene activation detected by in situ hybridization in radiation-induced rat skin tumors; (4) amplification of the c-myc oncogene in radiation-induced rat skin tumors as a function of LET; and (5) transformation of rat skin keratinocytes by ionizing radiation in combination with c-Ki-ras and c-myc oncogenes. 111 refs., 13 figs., 12 tabs.
Date: January 1, 1991
Creator: Burns, F.J.
Object Type: Report
System: The UNT Digital Library
Mammals of the Savannah River Site (open access)

Mammals of the Savannah River Site

This book is designed to be used as a field guide, reference book, bibliography, and introduction to the basic biology and ecology of the 54 mammal species that currently or potentially exist on or near the Savannah River Site (SRS). For 50 of these species, we present basic descriptions, distinguishing morphological features, distribution and habitat preferences, food habits, reproductive biology, social behavior, ecological relationships with other species, and economic importance to man. For those species that have been studied on the SRS, we summarize the results of these studies. Keys and illustrations are provided for whole body and skull identification. A selected glossary defines technical terminology. Illustrations of tracks of the more common larger mammals will assist in field identifications. We also summarize the results of two major long-term SRS studies, The Forbearer Census'' and White-tailed Deer Studies''. A cross-indexed list of over 300 SRS publications on mammals classifies each publication by 23 categories such as habitat, reproduction, genetics, etc., and also for each mammal species. The 149 Master's theses and Ph.D. dissertations that have been conducted at the Savannah River Ecology Laboratory are provided as additional references.
Date: January 1, 1991
Creator: Cothran, E.G.; Smith, M.H.; Wolff, J.O. & Gentry, J.B.
Object Type: Report
System: The UNT Digital Library
Proceedings of the 10th international workshop on ECR ion sources (open access)

Proceedings of the 10th international workshop on ECR ion sources

This report contains papers on the following topics: Recent Developments and Future Projects on ECR Ion Sources; Operation of the New KVI ECR Ion Source at 10 GHz; Operational Experience and Status of the INS SF-ECR Ion Source; Results of the New ECR4'' 14.5 GHz ECRIS; Preliminary Performance of the AECR; Experimental Study of the Parallel and Perpendicular Particle Losses from an ECRIS Plasma; Plasma Instability in Electron Cyclotron Resonance Heated Ion Sources; The Hyperbolic Energy Analyzer; Status of ECR Source Development; The New 10 GHz CAPRICE Source; First Operation of the Texas A M ECR Ion Source; Recent Developments of the RIKEN ECR Ion Sources; The 14 GHz CAPRICE Source; Characteristics and Potential Applications of an ORNL Microwave ECR Multicusp Plasma Ion Source; ECRIPAC: The Production and Acceleration of Multiply Charged Ions Using an ECR Plasma; ECR Source for the HHIRF Tandem Accelerator; Feasibility Studies for an ECR-Generated Plasma Stripper; Production of Ion Beams by using the ECR Plasmas Cathode; A Single Stage ECR Source for Efficient Production of Radioactive Ion Beams; The Single Staged ECR Source at the TRIUMF Isotope Separator TISOL; The Continuous Wave, Optically Pumped H{sup {minus}} Source; The H{sup +} ECR Source for the LAMPF …
Date: January 1, 1991
Creator: Meyer, F W & Kirkpatrick, M I
Object Type: Article
System: The UNT Digital Library
Geothermal direct use engineering and design guidebook (open access)

Geothermal direct use engineering and design guidebook

The Geothermal Direct Use Engineering and Design Guidebook is designed to be a comprehensive, thoroughly practical reference guide for engineers and designers of direct heat projects. These projects could include the conversion of geothermal energy into space heating and cooling of buildings, district heating, greenhouse heating, aquaculture and industrial processing. The Guidebook is directed at understanding the nature of geothermal resources and the exploration of the resources, fluid sampling techniques, drilling, and completion of geothermal wells through well testing, and reservoir evaluation. It presents information useful to engineers on the specification of equipment including well pumps, piping, heat exchangers, space heating equipment, heat pumps and absorption refrigeration. A compilation of current information about greenhouse aquaculture and industrial applications is included together with a discussion of engineering cost analysis, regulation requirements, and environmental consideration. The purpose of the Guidebook is to provide an integrated view for the development of direct use projects for which there is a very large potential in the United States.
Date: January 1, 1991
Creator: Lienau, P. J. & Lunis, B. C. (eds.)
Object Type: Report
System: The UNT Digital Library
Evaluation of oil shale bitumen as a pavement asphalt additive to reduce moisture damage susceptibility (open access)

Evaluation of oil shale bitumen as a pavement asphalt additive to reduce moisture damage susceptibility

An unrefined shale bitumen was evaluated as an agent to reduce moisture damage susceptibility of asphalt aggregate mixtures. Some activity was observed but less than might have been expected based on the molecular weight and nitrogen content of the bitumen. The counter effects of free carboxylic acids, which are known to be variable in asphalt and which are also present in the unrefined bitumen, appear to diminish the activity of the bitumen to inhibit moisture damage. 5 refs., 1 tab.
Date: January 1, 1991
Creator: Robertson, R. E.; Harnsberger, P. M. & Wolf, J. M.
Object Type: Report
System: The UNT Digital Library
HEMP emergency planning and operating procedures for electric power systems (open access)

HEMP emergency planning and operating procedures for electric power systems

Investigations of the impact of high-altitude electromagnetic pulse (HEMP) on electric power systems and electrical equipment have revealed that HEMP creates both misoperation and failures. These events result from both the early time E[sub 1] (steep-front pulse) component and the late time E[sub 3] (geomagnetic perturbations) component of HEMP. In this report a HEMP event is viewed in terms of its marginal impact over classical power system disturbances by considering the unique properties and consequences of HEMP. This report focuses on system-wide electrical component failures and their potential consequences from HEMP. In particular, the effectiveness of planning and operating procedures for electric systems is evaluated while under the influence of HEMP. This assessment relies on published data and characterizes utilities using the North American Electric Reliability Council's regions and guidelines to model electric power system planning and operations. Key issues addressed by the report include how electric power systems are affected by HEMP and what actions electric utilities can initiate to reduce the consequences of HEMP. The report also reviews the salient features of earlier HEMP studies and projects, examines technology trends in the electric power industry which are affected by HEMP, characterizes the vulnerability of power systems to HEMP, …
Date: January 1, 1991
Creator: Reddoch, T. W. & Markel, L. C. (Electrotek Concepts, Inc., Knoxville, TN (United States))
Object Type: Report
System: The UNT Digital Library
Fabrication of oxide dispersion strengthened ferritic clad fuel pins (open access)

Fabrication of oxide dispersion strengthened ferritic clad fuel pins

A resistance butt welding procedure was developed and qualified for joining ferritic fuel pin cladding to end caps. The cladding are INCO MA957 and PNC ODS lots 63DSA and 1DK1, ferritic stainless steels strengthened by oxide dispersion, while the end caps are HT9 a martensitic stainless steel. With adequate parameter control the weld is formed without a residual melt phase and its strength approaches that of the cladding. This welding process required a new design for fuel pin end cap and weld joint. Summaries of the development, characterization, and fabrication processes are given for these fuel pins. 13 refs., 6 figs., 1 tab.
Date: January 1, 1991
Creator: Zirker, L.R. (Argonne National Lab., Idaho Falls, ID (United States)); Bottcher, J.H. (Argonne National Lab., IL (United States)); Shikakura, S. (Power Reactor and Nuclear Fuel Development Corp., Oarai (Japan)); Tsai, C.L. (Ohio State Univ., Columbus, OH (United States). Dept. of Welding Engineering) & Hamilton, M.L. (Pacific Northwest Lab., Richland, WA (United States))
Object Type: Article
System: The UNT Digital Library
Nuclear models relevant to evaluation (open access)

Nuclear models relevant to evaluation

The widespread use of nuclear models continues in the creation of data evaluations. The reasons include extension of data evaluations to higher energies, creation of data libraries for isotopic components of natural materials, and production of evaluations for radiative target species. In these cases, experimental data are often sparse or nonexistent. As this trend continues, the nuclear models employed in evaluation work move towards more microscopically-based theoretical methods, prompted in part by the availability of increasingly powerful computational resources. Advances in nuclear models applicable to evaluation will be reviewed. These include advances in optical model theory, microscopic and phenomenological state and level density theory, unified models that consistently describe both equilibrium and nonequilibrium reaction mechanism, and improved methodologies for calculation of prompt radiation from fission. 84 refs., 8 figs.
Date: January 1, 1991
Creator: Arthur, E. D.; Chadwick, M. B.; Hale, G. M. & Young, P. G.
Object Type: Article
System: The UNT Digital Library
History of the youngest members of the Valles Rhyolite, Valles caldera, New Mexico using ESR dating method (open access)

History of the youngest members of the Valles Rhyolite, Valles caldera, New Mexico using ESR dating method

The cooling history of the Valles caldera was studied by the electron spin resonance (ESR) dating method using Al and Ti centers in quartz grains which were separated from the youngest units of the Valles Rhyolite. The ESR apparent ages are much younger than fission track ages and {sup 39}Ar- {sup 40}Ar ages. Three possibilities are suggested, the first is that the ESR ages are real, the second is that ESR method did not work for these samples, and the third is that about 10--40 ka, the signal intensity was partially reduced by a thermal event such as proposed by Harrison et al. (1986). Research on the first and second possibilities is continuing. The third possibility might explain the difference between ESR ages and those by other methods (fission track and {sup 39}Ar- {sup 40}Ar). ESR dating has produced new insights regarding the history of the Valles caldera.
Date: January 1, 1991
Creator: Ogoh, K.; Toyoda, S.; Ikeda, S.; Ikeya, M. (Osaka Univ., Toyonaka (Japan). Dept. of Physics) & Goff, F. (Los Alamos National Lab., NM (United States))
Object Type: Article
System: The UNT Digital Library
Quantification and reduction of the uncertainty in mass balance models by Monte Carlo analysis of prior data (open access)

Quantification and reduction of the uncertainty in mass balance models by Monte Carlo analysis of prior data

The general objective of this workshop is to investigate and discuss methods by which uncertainties in mass balance models for toxics in the Great Lakes may be reduced. As described by the workshop prospectus, this paper is focused on problems of reducing (and quantifying) uncertainty as they relate to in situ field observations/system response measurements for the establishment of initial conditions, boundary conditions, calibration/confirmation data sets, and model post-audit data sets.'' I have taken this description to refer not only to the evaluation of uncertainty in the field observations themselves, but also to the uncertainty associated the analyses of in situ observations as they interact in the overall modeling process. Thus, I will be concerned here with quantification and reduction of uncertainty both (1) as they may be applied to descriptions of the system that is being modeled and (2) as they may be associated with model simulations.
Date: January 1, 1991
Creator: Lesht, B.M.
Object Type: Article
System: The UNT Digital Library
Advances in downhole sampling of high temperature solutions (open access)

Advances in downhole sampling of high temperature solutions

A fluid sampler capable of sampling hot and/or deep wells has been developed at Los Alamos National Laboratory. In collaboration with Leutert Instruments, an off-the-shelf sampler design was modified to meet gas-tight and minimal chemical reactivity/contamination specifications for use in geothermal wells and deep ocean drillholes. This downhole sampler has been routinely used at temperatures up to 300{degrees}C and hole depths of greater than 5 km. We have tested this sampler in various continental wells, including Valles Caldera VC-2a and VC-2b, German KTB, Cajon Pass, and Yellowstone Y-10. Both the standard commercial and enhanced samplers have also been used to obtain samples from a range of depths in the Ocean Drilling Project's hole 504B and during recent mid-ocean ridge drilling efforts. The sampler has made it possible to collect samples at temperatures and conditions beyond the limits of other tools with the added advantage of chemical corrosion resistance.
Date: January 1, 1991
Creator: Bayhurst, Gregory K. & Janecky, D. R.
Object Type: Article
System: The UNT Digital Library
A re-evaluation of the Moyuta geothermal system, Southern Guatemala (open access)

A re-evaluation of the Moyuta geothermal system, Southern Guatemala

Chemical and isotopic data from four fumarole sites combined with prefeasibility assessments obtained in the 1970s have resulted in a re-evaluation of the Moyuta geothermal system. Moyuta consists of an east-west trending complex of Quaternary andesite/dacite domes and flows cut by north-trending faults. Areas of fumaroles, acid springs, and bicarbonate-rich thermal springs flank the north and south sides of the volcanic complex. Chloride-rich thermal springs discharge along rivers at lower elevations around the Moyuta highland. The distribution of thermal features indicates that deep reservoir fluid rises convectively near the axis of volcanism. Geochemical data suggest that there are two subsystems having temperatures of about 210{degrees}C (north flank) and 170{degrees}C (south flank). Exploration wells sited near the most northerly fumarole (Azulco) achieved temperatures of {le}113{degrees}C at 1004 m depth. We suggest the fumaroles occur above hydrothermal outflow plumes confined to vertical, fault-controlled conduits. Better drilling sites occur closer to the intersections of the north trending faults and the Quaternary volcanic axis. 21 refs., 7 figs., 2 tabs.
Date: January 1, 1991
Creator: Goff, F.; Adams, A.; Trujillo, P. E.; Counce, D.; Janik, C.; Fahlquist, L. et al.
Object Type: Article
System: The UNT Digital Library
Department of Petroleum Engineering and Center for Petroleum and Geosystems Engineering annual report, 1990--1991 academic year (open access)

Department of Petroleum Engineering and Center for Petroleum and Geosystems Engineering annual report, 1990--1991 academic year

The Department of Petroleum Engineering at The University of Texas at Austin is one of more than 20 such departments in the United States and more than 40 worldwide. The department has more than 20 faculty members and, as of the fall of 1990, 146 undergraduate and 156 graduate students. During the 1990--91 academic year, undergraduate enrollment is up slightly from the several downturns that began in 1986; graduate enrollment continues to increase, significantly in the number of Ph.D. candidates enrolled. The 1990--91 academic year was one of consolidation of gains. A remote teaching program in the Midland-Odessa area was initiated. During 1991, the Center for Petroleum and Geosystems Engineering (CPGE) continued its large, diversified research activities related to oil, gas and geopressured/geothermal energy production, energy and mineral resources analysis, and added new research projects in other areas such as groundwater remediation. Many of these research projects included interdisciplinary efforts involving faculty, research scientists and graduate students in chemistry, mathematics, geology, geophysics, engineering mechanics, chemical engineering, microbiology and other disciplines. Several projects were undertaken in cooperation with either the Bureau of Economic Geology or the Institute for Geophysics at The University of Texas at Austin. Collaborative research projects with scientists …
Date: January 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
(Energy related studies utilizing microline thermochronology) (open access)

(Energy related studies utilizing microline thermochronology)

In our first year of the current funding cycle, we have investigated three interrelated aspects of K-feldspar thermochronology; (1) the Ar diffusion properties and microstructures of K-feldspars, (2) the thermal evolution of the Valles Caldera and (3) the continued development of microanalysis. Results of TEM and light microscopy on heated and unheated samples of MH-10 K-feldspar reveal three classes of substructure are present: (1) cross hatched extinction is common and there is almost no albite/pericline twinning, only tweed microstructure; (2) 5--10 vol. % of this K-feldspar are turbid zones with complex twin and tweed structures at the sub-micron scale and numerous dislocation and strain features; (3) about 20% of the K-feldspar is comprised of 0.01 {times} 0.2-1{mu}m albite exsolution lamellae. The network of fractured/turbid zones divides the sample into blocks of approximately 50 {mu}m and the separation between albite exsolution lamellae produce K-feldspar domains of the order 0.1 {mu}m. Independent crushing and diffusion experiments suggest the scale of the largest domain is order ten's of micron whereas the smallest domain size is inferred to be {approximately}0.1 {mu}m. Many, and perhaps most, alkali feldspars contain diffusion domains with activation energies that may vary by as much as 8 kcal/mol. An extraordinary …
Date: January 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The drilling of a horizontal well in a mature oil field (open access)

The drilling of a horizontal well in a mature oil field

This report documents the drilling of a medium radius horizontal well in the Bartlesville Sand of the Flatrock Field, Osage County, Oklahoma by Rougeot Oil and Gas Corporation (Rougeot) of Sperry, Oklahoma. The report includes the rationale for selecting the particular site, the details of drilling the well, the production response, conclusions reached, and recommendations made for the future drilling of horizontal wells. 11 figs., 2 tabs.
Date: January 1, 1991
Creator: Rougeot, John E. & Lauterbach, Kurt A.
Object Type: Report
System: The UNT Digital Library
Security guide for subcontractors (open access)

Security guide for subcontractors

This security guide of the Department of Energy covers contractor and subcontractor access to DOE and Mound facilities. The topics of the security guide include responsibilities, physical barriers, personnel identification system, personnel and vehicular access controls, classified document control, protecting classified matter in use, storing classified matter repository combinations, violations, security education clearance terminations, security infractions, classified information nondisclosure agreement, personnel security clearances, visitor control, travel to communist-controlled or sensitive countries, shipment security, and surreptitious listening devices.
Date: January 1, 1991
Creator: Adams, R.C.
Object Type: Report
System: The UNT Digital Library
Phase control in a two-element folded waveguide array (open access)

Phase control in a two-element folded waveguide array

A pair of folded waveguides have been used to determine the mutual coupling and to measure the field distributions for the magnetic field components for single units and for a pair. The phase difference controls the field distribution and the Fourier spectrum. 3 refs., 4 figs.
Date: January 1, 1991
Creator: Haste, G.R.
Object Type: Article
System: The UNT Digital Library
Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system (open access)

Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system

A conceptual geologic model of the Roosevelt Hot Springs hydrothermal system was developed by a review of the available literature. The hydrothermal system consists of a meteoric recharge area in the Mineral Mountains, fluid circulation paths to depth, a heat source, and an outflow plume. A conceptual model based on the available data can be simulated in the native state using parameters that fall within observed ranges. The model temperatures, recharge rates, and fluid travel times are sensitive to the permeability in the Mineral Mountains. The simulation results suggests the presence of a magma chamber at depth as the likely heat source. A two-dimensional study of the hydrothermal system can be used to establish boundary conditions for further study of the geothermal reservoir.
Date: January 1, 1991
Creator: Faulder, D. D.
Object Type: Article
System: The UNT Digital Library