CFD SIMULATION OF PROPOSED VALIDATION DATA FOR A FLOW PROBLEM RECONFIGURED TO ELIMINATE AN UNDESIRABLE FLOW INSTABILITY (open access)

CFD SIMULATION OF PROPOSED VALIDATION DATA FOR A FLOW PROBLEM RECONFIGURED TO ELIMINATE AN UNDESIRABLE FLOW INSTABILITY

The U. S. Department of Energy (DOE) is supporting the development of a next generation nuclear plant (NGNP), which will be based on a very high temperature reactor (VHTR) design. The VHTR is a single-phase helium-cooled reactor wherein the helium will be heated initially to 750 °C and later to temperatures approaching 1000 °C. The high temperatures are desired to increase reactor efficiency and to provide a heat source for the manufacture of hydrogen and other applications. While computational fluid dynamics (CFD) has not been used in the past to design or license nuclear reactors in the U. S., it is expected that CFD will be used in the design and safety analysis of forthcoming designs. This is partly because of the maturity of CFD and partly because detailed information is desired of the flow and heat transfer inside the reactor to avoid hot spots and other conditions that might compromise reactor safety. Numerical computations of turbulent flow should be validated against experimental data for flow conditions that contain some or all of the physics expected in the thermal fluid machinery of interest. To this end, a scaled model of a narrow slice of the lower plenum of the prismatic …
Date: August 1, 2010
Creator: Johnson, Richard W. & McIlroy, Hugh M.
Object Type: Article
System: The UNT Digital Library
The CGC and the Glasma: Two Lectures at the Yukawa Institute (open access)

The CGC and the Glasma: Two Lectures at the Yukawa Institute

These lectures present the theory of the Color Glass Condensate (CGC) and the Glasma in an elementary and intuitive manner. This matter controls the high energy limit of QCD. The CGC is the universal limit for the components of a hadron wavefunction important for high energy scattering processes. It is a highly coherent, extremely high energy density ensemble of gluon states. The Glasma is matter produced in the collision of CGCs of two hadrons. It has properties much different from those of the CGC, and is produced in a very short time after the collision. It eventually evolves from the the Color Glass Condensate initial conditions into a Quark Gluon Plasma. We can visualize the collision of two high energy hadrons as shown in Fig. 1. Before the collision, two hadrons appear as Lorentz contracted sheets approaching one another at near light speed. These we will later describe as two sheets of Colored Glass. In a very short time, the sheets of Color Glass interpenetrate one another. This we think of as the initial singularity for the collision. This is of course not a real singularity for finite collision energy, but we will see it becomes one in the limit …
Date: August 10, 2010
Creator: McLerran, L.
Object Type: Article
System: The UNT Digital Library
Characterization of High Level Waste from a Hybrid LIFE Engine for Enhanced Repository Performance (open access)

Characterization of High Level Waste from a Hybrid LIFE Engine for Enhanced Repository Performance

None
Date: August 25, 2010
Creator: Beckett, E. & Fratoni, M.
Object Type: Report
System: The UNT Digital Library
Characterization of soil water content variability and soil texture using GPR groundwave techniques (open access)

Characterization of soil water content variability and soil texture using GPR groundwave techniques

Accurate characterization of near-surface soil water content is vital for guiding agricultural management decisions and for reducing the potential negative environmental impacts of agriculture. Characterizing the near-surface soil water content can be difficult, as this parameter is often both spatially and temporally variable, and obtaining sufficient measurements to describe the heterogeneity can be prohibitively expensive. Understanding the spatial correlation of near-surface soil water content can help optimize data acquisition and improve understanding of the processes controlling soil water content at the field scale. In this study, ground penetrating radar (GPR) methods were used to characterize the spatial correlation of water content in a three acre field as a function of sampling depth, season, vegetation, and soil texture. GPR data were acquired with 450 MHz and 900 MHz antennas, and measurements of the GPR groundwave were used to estimate soil water content at four different times. Additional water content estimates were obtained using time domain reflectometry measurements, and soil texture measurements were also acquired. Variograms were calculated for each set of measurements, and comparison of these variograms showed that the horizontal spatial correlation was greater for deeper water content measurements than for shallower measurements. Precipitation and irrigation were both shown to …
Date: August 15, 2010
Creator: Grote, K.; Anger, C.; Kelly, B.; Hubbard, S. & Rubin, Y.
Object Type: Article
System: The UNT Digital Library
Characterization of the DT Ice Layer in a Fusion Capsule Using a Two-Dimensional X-Ray Shearing Interferometer (open access)

Characterization of the DT Ice Layer in a Fusion Capsule Using a Two-Dimensional X-Ray Shearing Interferometer

None
Date: August 9, 2010
Creator: Baker, K L
Object Type: Article
System: The UNT Digital Library
Chp Regional Application Centers: Activities and Selected Results (open access)

Chp Regional Application Centers: Activities and Selected Results

Between 2001 and 2005, the U.S. Department of Energy (DOE) created a set of eight Regional Application Centers (RACs) to facilitate the development and deployment of Combined Heat and Power (CHP) technologies. By utilizing the thermal energy that is normally wasted when electricity is produced at central generating stations, Combined Heat and Power installations can save substantial amounts of energy compared to more traditional technologies. In addition, the location of CHP facilities at or near the point of consumption greatly reduces or eliminates electric transmission and distribution losses. The regional nature of the RACs allows each one to design and provide services that are most relevant to the specific economic and market conditions in its particular geographic area. Between them, the eight RACs provide services to all 50 states and the District of Columbia. Through the end of the federal 2009 fiscal year (FY 2009), the primary focus of the RACs was on providing CHP-related information to targeted markets, encouraging the creation and adoption of public policies and incentives favorable to CHP, and providing CHP users and prospective users with technical assistance and support on specific projects. Beginning with the 2010 fiscal year, the focus of the regional centers broadened …
Date: August 1, 2010
Creator: Schweitzer, Martin
Object Type: Report
System: The UNT Digital Library
Chromosomal Rainbows detect Oncogenic Rearrangements of Signaling Molecules in Thyroid Tumors (open access)

Chromosomal Rainbows detect Oncogenic Rearrangements of Signaling Molecules in Thyroid Tumors

Altered signal transduction can be considered a hallmark of many solid tumors. In thyroid cancers the receptor tyrosine kinase (rtk) genes NTRK1 (Online Mendelian Inheritance in Man = OMIM *191315, also known as 'TRKA'), RET ('Rearranged during Transfection protooncogene', OMIM *164761) and MET (OMIM *164860) have been reported as activated, rearranged or overexpressed. In many cases, a combination of cytogenetic and molecular techniques allows elucidation of cellular changes that initiate tumor development and progression. While the mechanisms leading to overexpression of the rtk MET gene remain largely unknown, a variety of chromosomal rearrangements of the RET or NTKR1 gene could be demonstrated in thyroid cancer. Abnormal expressions in these tumors seem to follow a similar pattern: the rearrangement translocates the 3'-end of the rtk gene including the entire catalytic domain to an expressed gene leading to a chimeric RNA and protein with kinase activity. Our research was prompted by an increasing number of reports describing translocations involving ret and previously unknown translocation partners. We developed a high resolution technique based on fluorescence in situ hybridization (FISH) to allow rapid screening for cytogenetic rearrangements which complements conventional chromosome banding analysis. Our technique applies simultaneous hybridization of numerous probes labeled with different …
Date: August 19, 2010
Creator: O'Brien, Benjamin; Jossart, Gregg H.; Ito, Yuko; Greulich-Bode, Karin M.; Weier, Jingly F.; Munne, Santiago et al.
Object Type: Report
System: The UNT Digital Library
Clone Bacterial Thermal Stable Enzymes in T. Reesei: Cooperative Research and Development Final Report, CRADA Number CRD-01-00105 (open access)

Clone Bacterial Thermal Stable Enzymes in T. Reesei: Cooperative Research and Development Final Report, CRADA Number CRD-01-00105

The focus of this CRADA was on improving the efficacy of GCI's primary host for commercial cellulase production, Trichoderma reesei.
Date: August 1, 2010
Creator: Himmel, M. E.
Object Type: Report
System: The UNT Digital Library
Closure Report (CR) for Corrective Action Unit (CAU) 41: Area 27 Landfills with Errata Sheet, Revision 0 (open access)

Closure Report (CR) for Corrective Action Unit (CAU) 41: Area 27 Landfills with Errata Sheet, Revision 0

The closure report for CAU 41 is just a one page summary listing the coordinates of the landfill which were given at the time (1996) in Nevada State Plan Coordinates - North American Datum of 1983. The drawing of the use restricted site also listed the coordinates in Nevada State Plan Coordinates - North American Datum of 1983. In the ensuing years the reporting of coordinates has been standardized so that all coordinates are reported in the same manner, which is: NAD 27 UTM Zone 11 N, meters. This Errata Sheet updates the coordinate reporting to the currently accepted method and includes an aerial photo showing the landfill with the coordinates listed showing the use restricted area.
Date: August 10, 2010
Creator: Services, Navarro Nevada Environmental
Object Type: Report
System: The UNT Digital Library
Closure Report (CR) for Corrective Action Unit (CAU) 91: Area 3 U-3fi Injection Well with Errata Sheet and Certification, Revision 0 (open access)

Closure Report (CR) for Corrective Action Unit (CAU) 91: Area 3 U-3fi Injection Well with Errata Sheet and Certification, Revision 0

The closure report for CAU 91 has no Use Restriction Form or drawing/map included in the document to describe the use restricted area, however, Section 3.3.3 states that the site will be fenced and signage placed indicating the area as a Resource Conservation and Recovery Act (RCRA) Unit. The drawing that was placed in the FFACO indicating the use restricted area lists the coordinates for the RCRA Unit in Nevada State Plan Coordinates - North American Datum of 1983. In the ensuing years the reporting of coordinates has been standardized so that all coordinates are reported in the same manner, which is: NAD 27 UTM Zone 11 N, meters. This Errata Sheet updates the coordinate reporting to the currently accepted method and includes an aerial photo showing the RCRA Unit with the coordinates listed showing the use restricted area.
Date: August 10, 2010
Creator: Services, Navarro Nevada Environmental
Object Type: Report
System: The UNT Digital Library
Closure Report for Corrective Action Unit 329: Area 22 Desert Rock Airstrip Fuel Spill with Errata Sheet, Revision 0 (open access)

Closure Report for Corrective Action Unit 329: Area 22 Desert Rock Airstrip Fuel Spill with Errata Sheet, Revision 0

In Appendix 0, Use Restriction (UR) Form, the drawing of the use restricted area shows the incorrect coordinates for the use restricted area, the coordinates on the drawing do not match the approved UR Form. The coordinates have been verified and this Errata Sheet replaces the drawing of the use restricted area with an aerial photo showing the use restricted area and the correct coordinates that match the approved UR Form.
Date: August 10, 2010
Creator: Services, Navarro Nevada Environmental
Object Type: Report
System: The UNT Digital Library
Closure Report for Corrective Action Unit 399: Area 18 Disposal Site (open access)

Closure Report for Corrective Action Unit 399: Area 18 Disposal Site

The closure report for CAU 399 is just a one page summary listing the coordinates of the disposal site which were given at the time (1995) in Nevada State Plan Coordinates - North American Datum of 1983. The drawing of the use restricted site also listed the coordinates in Nevada State Plan Coordinates - North American Datum of 1983. In the ensuing years the reporting of coordinates has been standardized so that all coordinates are reported in the same manner, which is: NAD 27 UTM Zone 11 N, meters. This Errata Sheet updates the coordinate reporting to the currently accepted method and includes an aerial photo showing the disposal site with the coordinates listed showing the use restricted area.
Date: August 10, 2010
Creator: Services, Navarro Nevada Environmental
Object Type: Report
System: The UNT Digital Library
Co-Simulation of Building Energy and Control Systems with the Building Controls Virtual Test Bed (open access)

Co-Simulation of Building Energy and Control Systems with the Building Controls Virtual Test Bed

This article describes the implementation of the Building Controls Virtual Test Bed (BCVTB). The BCVTB is a software environment that allows connecting different simulation programs to exchange data during the time integration, and that allows conducting hardware in the loop simulation. The software architecture is a modular design based on Ptolemy II, a software environment for design and analysis of heterogeneous systems. Ptolemy II provides a graphical model building environment, synchronizes the exchanged data and visualizes the system evolution during run-time. The BCVTB provides additions to Ptolemy II that allow the run-time coupling of different simulation programs for data exchange, including EnergyPlus, MATLAB, Simulink and the Modelica modelling and simulation environment Dymola. The additions also allow executing system commands, such as a script that executes a Radiance simulation. In this article, the software architecture is presented and the mathematical model used to implement the co-simulation is discussed. The simulation program interface that the BCVTB provides is explained. The article concludes by presenting applications in which different state of the art simulation programs are linked for run-time data exchange. This link allows the use of the simulation program that is best suited for the particular problem to model building heat transfer, …
Date: August 22, 2010
Creator: Wetter, Michael
Object Type: Article
System: The UNT Digital Library
Coherence Properties of the LCLS (open access)

Coherence Properties of the LCLS

The LINAC Coherent Light Source (LCLS), an X-Ray free-electron laser(FEL) based on the self amplified spontaneous emission principle, has recently come on-line. For many users it is desirable to have an idea of the level of transverse coherence of the X-Ray beam produced. In this paper, we analyze the output of GENESIS simulations of electrons traveling through the FEL. We first test the validity of an approach that ignores the details of how the beam was produced, and instead, by assuming a Gaussian-Schell model of transverse coherence, predicts the level of transverse coherence simply through looking at the beam radius at several longitudinal slices. We then develop a Markov chain Monte Carlo approach to calculating the degree of transverse coherence, which offers a {approx}100-fold speedup compared to the brute-force algorithm previously in use. We find the beam highly coherent. Using a similar Markov chain Monte Carlo approach, we estimate the reasonability of assuming the beam to have a Gaussian-Schell model of transverse coherence, with inconclusive results.
Date: August 25, 2010
Creator: Ocko, Samuel
Object Type: Report
System: The UNT Digital Library
Cold Nuclear Matter Effects on J/psi Production: Intrinsic and Extrinsic Transverse Momentum Effects (open access)

Cold Nuclear Matter Effects on J/psi Production: Intrinsic and Extrinsic Transverse Momentum Effects

Cold nuclear matter effects on J/{psi} production in proton-nucleus and nucleus-nucleus collisions are evaluated taking into account the specific J/{psi}-production kinematics at the partonic level, the shadowing of the initial parton distributions and the absorption in the nuclear matter. We consider two different parton processes for the c{bar c}-pair production: one with collinear gluons and a recoiling gluon in the final state and the other with initial gluons carrying intrinsic transverse momentum. Our results are compared to RHIC observables. The smaller values of the nuclear modification factor R{sub AA} in the forward rapidity region (with respect to the mid rapidity region) are partially explained, therefore potentially reducing the need for recombination effects.
Date: August 26, 2010
Creator: Ferreiro, E.G.; U., /Santiago de Compostela; Fleuret, F.; Polytechnique, /Ecole; Lansberg, J.P.; U., /Heidelberg et al.
Object Type: Article
System: The UNT Digital Library
Collaborative Visualization for Large-Scale Accelerator Electromagnetic Modeling (open access)

Collaborative Visualization for Large-Scale Accelerator Electromagnetic Modeling

In the Phase I SBIR we proposed a ParaView-based solution to provide an environment for individuals to actively collaborate in the visualization process. The technical objectives of Phase I were: (1) to determine the set of features required for an effect collaborative system; (2) to implement a two-person collaborative prototype; and (3) to implement key collaborative features such as control locking and annotation. Accordingly, we implemented a ParaView-based collaboration prototype with support for collaborating with up to four simultaneous clients. We also implemented collaborative features such as control locking, chatting, annotation etc. Due to in part of the flexibility provided by the ParaView framework and the design features implemented in the prototype, we were able to support collaboration with multiple views, instead of a simple give as initially proposed in Phase I. In this section we will summarize the results we obtained during the Phase I project. ParaView is complex, scalable, client-server application framework built on top of the VTK visualization engine. During the implementation of the Phase I prototype, we realized that the ParaView framework naturally supports collaboration technology; hence we were able to go beyond the proposed Phase I prototype in several ways. For example, we were able …
Date: August 25, 2010
Creator: Schussman, Greg
Object Type: Report
System: The UNT Digital Library
Collective Quartics from Simple Groups (open access)

Collective Quartics from Simple Groups

This article classifies Little Higgs models that have collective quartic couplings. There are two classes of collective quartics: Special Cosets and Special Quartics. After taking into account dangerous singlets, the smallest Special Coset models are SU(5)/SO(5) and SU(6)/Sp(6). The smallest Special Quartic model is SU(5)/SU(3) x SU(2) x U(1) and has not previously been considered as a candidate Little Higgs model.
Date: August 26, 2010
Creator: Hook, Anson & Wacker, Jay G.
Object Type: Article
System: The UNT Digital Library
Collector/Receiver Characterization (Fact Sheet) (open access)

Collector/Receiver Characterization (Fact Sheet)

Fact sheet describing NREL CSP Program capabilities for collector/receiver characterization: determining optical efficiency, measuring heat loss, developing and testing concentrators, concentrating the sun's power, and optically characterizing CSP plants.
Date: August 1, 2010
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Commercial Building Design Pathways Using Optimization Analysis: Preprint (open access)

Commercial Building Design Pathways Using Optimization Analysis: Preprint

Whole-building simulation and analysis has demonstrated a significant energy savings potential in a wide variety of design projects. Commercial building design, however, traditionally integrates simulation and modeling analyses too late in the design process to make a substantial impact on energy use. The National Renewable Energy Laboratory (NREL) commercial building group created an optimization platform called Opt-E-Plus that uses multivariate and multi-objective optimization theory to navigate a large parameter space and find economically valid, energy-saving solutions. The analysis results provide designers and engineers valuable information that influences the design. The pathways are not full 'construction ready' design alternatives; rather, they offer guidance about performance and cost criteria to reach a range of energy and economic goals. Having this knowledge early in the design phase helps designers establish project goals and direct the design pathway before they make important decisions. Opt-E-Plus has been deployed on several projects, including a retrofit mixed-use building, a new NREL office building, and several nationwide design guides. Each of these projects had different design criteria, goals, and audiences. In each case the analysis results provided pathways that helped inform the design process.
Date: August 1, 2010
Creator: Long, N.; Hirsch, A.; Lobato, C. & Macumber, D.
Object Type: Article
System: The UNT Digital Library
Commercialization of High Efficiency Low Cost CIGS Technology Based on Electroplating: Final Technical Progress Report, 28 September 2007 - 30 June 2009 (open access)

Commercialization of High Efficiency Low Cost CIGS Technology Based on Electroplating: Final Technical Progress Report, 28 September 2007 - 30 June 2009

This report describes SoloPower's work as a Photovoltaic Technology Incubator awardee within the U.S. Department of Energy's Solar Energy Technologies Program. The term of this subcontract with the National Renewable Energy Laboratory was two years. The project focused on SoloPower's electrodeposition-based copper indium gallium (di)selenide (CIGS) technology. Under this subcontract, SoloPower improved the quality of its flexible metal substrates, increased the size of its solar cells from 0.5 cm2 to 120 cm2, increased the small-area cell efficiencies from near 11% to near 14%, demonstrated large-area cells, and developed a module manufacturing process.
Date: August 1, 2010
Creator: Basol, B.
Object Type: Report
System: The UNT Digital Library
Commissioning of the LHC Low Level RF System Remote Configuration Tools (open access)

Commissioning of the LHC Low Level RF System Remote Configuration Tools

The LHC Low Level RF system (LLRF) is a complex multi-loop system used to regulate the superconductive cavity gap voltage as well as to reduce the impedance presented by RF stations to the beam. The RF system can have a profound impact on the stability of the beam; a mis-configured RF system has the potential of causing longitudinal instabilities, beam diffusion and beam loss. To configure the RF station for operation, a set of parameters in the LLRF multi-loop system have to be defined. Initial system commissioning as well as ongoing operation requires a consistent method of computer based remote measurement and model-based design of each RF station feedback system. This paper describes the suite of Matlab tools used for configuring the LHC RF system during the start up in Nov2009-Feb2010. We present a brief overview of the tool, examples of commissioning results, and basics of the model-based design algorithms. This work complements our previous presentation, where the algorithms and methodology followed in the tools were described.
Date: August 26, 2010
Creator: Van Winkle, Daniel; Fox, John; Mastorides, Themis; Rivetta, Claudio; Baudrenghien, Philippe; Butterworth, Andrew et al.
Object Type: Article
System: The UNT Digital Library
Compact 400-Mhz Half-Wave Spoke Resonator Crab Cavity for the LHC Update (open access)

Compact 400-Mhz Half-Wave Spoke Resonator Crab Cavity for the LHC Update

Crab cavities are proposed for the LHC upgrade to improve the luminosity. There are two possible crab cavity installations for the LHC upgrade: the global scheme at Interaction Region (IR) 4 where the beam-beam separation is about 420-mm, and the local scheme at the IR5 where the beam-beam separation is only 194-mm. One of the design requirements as the result of a recent LHC-Crab cavity workshop is to develop a 400-MHz cavity design that can be utilized for either the global or local schemes at IR4 or IR5. Such a design would offer more flexibility for the final upgrade installation, as the final crabbing scheme is yet to be determined, and save R&D cost. The cavity size of such a design, however, is limited by the beam-beam separation at IR5 which can only accommodate a cavity with a horizontal size of about 145-mm, which is a design challenge for a 400-MHz cavity. To meet the new design requirements, we have developed a compact 400-MHz half-wave spoke resonator (HWSR) crab cavity that can fit into the tight spaces available at either IR4 or IR5. In this paper, we present the optimization of the HWSR cavity shape and the design of HOM, …
Date: August 26, 2010
Creator: Li, Zenghai; Xiao, Liling; Ng, Cho & Markiewicz, Thomas
Object Type: Article
System: The UNT Digital Library
COMPARISON OF SIMULATION CODES FOR MICROWAVE INSTABILITY IN BUNCHED BEAMS (open access)

COMPARISON OF SIMULATION CODES FOR MICROWAVE INSTABILITY IN BUNCHED BEAMS

In accelerator design, there is often a need to evaluate the threshold to the (longitudinal) microwave instability for a bunched beam in an electron storage ring. Several computational tools are available that allow them, once given the wakefield representing a ring, to numerically find the threshold current and to simulate the development of the instability. In this work, they present results of coputer simulations using two codes recently developed at the SLAC National Accelerator Laboratory: a Vlasov-Fokker-Planck (VFP) solver based on an algorithm by Warnock and Ellison, and a program that find the threshold from the linearized Vlasov equation. They apply the programs to find the instability threshold for three models of ring impedances: that of a Q = 1 resonator, of shielded coherent synchrotron radiation (CSR), and of a resistive wall. The first example is wel-bheaved, but the other two are singular wakes that need special care. Note that similar numerical studies of the threshold of a Q = 1 resonantor wake have been performed by Oide and Yokova, and others. They compare the results of the two programs and discuss their respective capabilities and limitations. In this report they assume the slippage factor {eta} is always positive. They …
Date: August 25, 2010
Creator: Bane, K.L.F.; Cai, Y. & Stupakov, G.
Object Type: Article
System: The UNT Digital Library
Competitive repair by naturally dispersed repetitive DNA during non-allelic homologous recombination (open access)

Competitive repair by naturally dispersed repetitive DNA during non-allelic homologous recombination

Genome rearrangements often result from non-allelic homologous recombination (NAHR) between repetitive DNA elements dispersed throughout the genome. Here we systematically analyze NAHR between Ty retrotransposons using a genome-wide approach that exploits unique features of Saccharomyces cerevisiae purebred and Saccharomyces cerevisiae/Saccharomyces bayanus hybrid diploids. We find that DNA double-strand breaks (DSBs) induce NAHR-dependent rearrangements using Ty elements located 12 to 48 kilobases distal to the break site. This break-distal recombination (BDR) occurs frequently, even when allelic recombination can repair the break using the homolog. Robust BDR-dependent NAHR demonstrates that sequences very distal to DSBs can effectively compete with proximal sequences for repair of the break. In addition, our analysis of NAHR partner choice between Ty repeats shows that intrachromosomal Ty partners are preferred despite the abundance of potential interchromosomal Ty partners that share higher sequence identity. This competitive advantage of intrachromosomal Tys results from the relative efficiencies of different NAHR repair pathways. Finally, NAHR generates deleterious rearrangements more frequently when DSBs occur outside rather than within a Ty repeat. These findings yield insights into mechanisms of repeat-mediated genome rearrangements associated with evolution and cancer.
Date: August 27, 2010
Creator: Hoang, Margaret L.; Tan, Frederick J.; Lai, David C.; Celniker, Sue E.; Hoskins, Roger A.; Dunham, Maitreya J. et al.
Object Type: Article
System: The UNT Digital Library