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The energetics and dynamics of free radicals, ions, and clusters (open access)

The energetics and dynamics of free radicals, ions, and clusters

The structure and energetics of free radicals, ions, and clusters have been investigated by photoelectron photoion coincidence (PEPICO) and analyzed with ab initio molecular orbital and statistical theory RRKM calculations. In these experiments, molecules are prepared in a molecular beam so that their internal as well as translational energies are cooled to near O K. The coincidence condition between energy analyzed electrons and their corresponding ions insures that the ions are energy selected. The primary experimental information includes ionization and fragment ion appearance energies, and the ion time of flight (TOF) distributions. The latter are obtained by using the energy selected electron as a start signal and the ion as the stop signal. These types of experiments allow us to measure the ion dissociation rates in the 10{sup 4} to 10{sup 7} sec {sup {minus}1} range. Such ions are commonly referred to a metastable ions. In addition, the TOF peak widths are related to the release of translational energy in the ion dissociation process. Perhaps the most important advance during the past year has been in the study of cluster photoionization. We have developed an experimental method for differentiating similar mass cluster ions based on the kinetic energy of the …
Date: March 1, 1992
Creator: Baer, T.
Object Type: Report
System: The UNT Digital Library
(National Institute for Petroleum and Energy Research) monthly progress report, February 1992 (open access)

(National Institute for Petroleum and Energy Research) monthly progress report, February 1992

For this period, research is divided into Energy Production Research and Fuels Research. Energy Production Research includes reservoir characterization, microbial enhanced oil recovery, thermal EOR, alkaline flooding, gas flooding, flood process modelling, permeability and porosity research. Fuels Research included analysis of heavy crudes, and thermochemistry of organic nitrogen- and diheteroatom-containing compounds. The research of the Supplemental Government Program is also discussed.
Date: March 1, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system (open access)

ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system

We have initiated studies that include radiation model validation, improved treatment of the three-dimensional structure of cloud-radiation interactions, and sensitivity runs that will unravel the role of cloud-convection-radiation interactions in the Pacific Sear Surface Temperatures and the overlying Walker and Hadley circulation. The research program is divided into three phases: (1) radiation, (2) cloud parameterization issues; (3) feedback and ocean-atmosphere interactions.
Date: March 5, 1992
Creator: Ramanathan, V. & Barnett, T.P.
Object Type: Report
System: The UNT Digital Library
Readily implemented enhanced sinusoid detection in noise (open access)

Readily implemented enhanced sinusoid detection in noise

Significant efforts have been devoted, spanning many years, to the problem of sinusoid detection in noise. Many of these efforts have produced superb, yet complex, algorithms which may be difficult to use for a wide segment of the Digital Signal Processing (DSP) community. This paper presents a simple, easily implemented and high effective method which solves this problem. This method severely degrades non-sinusoidal noise while leaving the embedded sinusoid(s) relatively undisturbed. The algorithm, simply put, exploits the difference between the net effect of integration and differentiation of sinusoids versus the effect of these operations on random noise and other signal sequences. The cross-correlation of sine wave with its differentiated (and/or integrated) self is quite high. Conversely, the cross-reduction of a noise sequence with its differentiated (and/or integrated) self is much lower. Therefore, it is reasonable to assume that for sequences consisting of a sinusoid in noise, significant signal-to-noise-ratios (SNRs) in the correlation results are achievable using a combination of differentiation (and/or integration) and cross-correlation operations on such sequences. This technique has been applied to actual Doppler radar data, as well as to synthesized data, with excellent improvement in signal detection capability. 4 refs.
Date: March 5, 1992
Creator: Lindsay, K.V.
Object Type: Report
System: The UNT Digital Library
Coal liquefaction process streams characterization and evaluation (open access)

Coal liquefaction process streams characterization and evaluation

CONSOL R D is conducting a three-year program to characterize process and product streams from direct coal liquefaction process development projects. The program objectives are two-fold: (1) to obtain and provide appropriate samples of coal liquids for the evaluation of analytical methodology, and (2) to support ongoing DOE-sponsored coal liquefaction process development efforts. The two broad objectives have considerable overlap and together serve to provide a bridge between process development and analytical chemistry.
Date: March 1, 1992
Creator: Robbins, G.A.; Brandes, S.D.; Winschel, R.A. & Burke, F.P.
Object Type: Report
System: The UNT Digital Library
Evaluation of airborne thermal, magnetic, and electromagnetic characterization technologies (open access)

Evaluation of airborne thermal, magnetic, and electromagnetic characterization technologies

The identification of Buried Structures (IBS) or Aerial Surveillance Project was initiated by the US Department of Energy (DOE) Office of Technology Development to demonstrate airborne methods for locating and identifying buried waste and ordnance at the Idaho National Engineering Laboratory (INEL). Two technologies were demonstrated: (a) a thermal infrared imaging system built by Martin Marietta Missile Systems and (b) a magnetic and electromagnetic (EM) geophysical surveying system operated by EBASCO Environmental. The thermal system detects small differences in ground temperature caused by uneven heating and cooling of the ground by the sun. Waste materials on the ground can be detected when the temperature of the waste is different than the background temperature. The geophysical system uses conventional magnetic and EM sensors. These sensors detect disturbances caused by magnetic or conductive waste and naturally occurring magnetic or conductive features of subsurface soils and rock. Both systems are deployed by helicopter. Data were collected at four INEL sites. Tests at the Naval Ordnance Disposal Area (NODA) were made to evaluate capabilities for detecting ordnance on the ground surface. Tests at the Cold Simulated Waste Demonstration Pit were made to evaluate capabilities for detecting buried waste at a controlled site, where the …
Date: March 1, 1992
Creator: Josten, N.E.
Object Type: Report
System: The UNT Digital Library
Nuclear Regulatory Commission Information Digest 1992 edition. Volume 4 (open access)

Nuclear Regulatory Commission Information Digest 1992 edition. Volume 4

The Nuclear Regulatory Commission Information Digest provides a summary of information about the US Nuclear Regulatory Commission (NRC), NRC's regulatory responsibilities, the activities NRC licenses, and general information on domestic and worldwide nuclear energy. This digest is a compilation of nuclear- and NRC-related data and is designed to provide a quick reference to major facts about the agency and industry it regulates. In general, the data cover 1975 through 1991, with exceptions noted. Information on generating capacity and average capacity factor for operating US commercial nuclear power reactors is obtained from monthly operating reports that are submitted directly to the NRC by the licensee. This information is reviewed by the NRC for consistency only and no independent validation and/or verification is performed.
Date: March 1, 1992
Creator: Olive, K
Object Type: Report
System: The UNT Digital Library
1988 Wet Deposition Temporal and Spatial Patterns in North America (open access)

1988 Wet Deposition Temporal and Spatial Patterns in North America

The focus of this report is on North American wet deposition temporal patterns from 1979 to 1988 and spatial patterns for 1988. It is the third in a series of reports that investigate the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1988 annual, winter, and summer periods. Temporal pattern analyses use a subset of 35 sites over a 10-year (1979--1988) period and an expanded subset of 137 sites, with greater spatial coverage, over a 7-year (1982--1988) period. The 10-year period represents the longest period with wet deposition monitoring data available that has a sufficient number of sites with data of known quality to allow a descriptive summary of annual temporal patterns. Sen's median trend estimate and Kendall's seasonal tau (KST) test are calculated for each ion species concentration and deposition at each site in both subsets.
Date: March 1, 1992
Creator: Simpson, J. C.; Olsen, A. R. & Bittner, E. A.
Object Type: Report
System: The UNT Digital Library
Demonstration of rapid and sensitive module leak certification for space station freedom (open access)

Demonstration of rapid and sensitive module leak certification for space station freedom

A leak detection and quantification demonstration using perflurocarbon tracer (PFT) technology was successfully performed at the NASA Marshall Space Flight Center on January 25, 1991. The real-time Dual Trap Analyzer (DTA) at one-half hour after the start of the first run gave an estimated leak rate of 0.7 mL/min. This has since been refined to be 1.15 {plus minus} 0.09 mL/min. The leak rates in the next three runs were determined to be 9.8 {plus minus} 0.7, {minus}0.4 {plus minus} 0.3, and 76 {plus minus} 6 mL/min, respectively. The theory on leak quantification in the steady-state and time-dependent modes for a single zone test facility was developed and applied to the above determinations. The laboratory PFT analysis system gave a limit-of-detection (LOD) of 0.05 fL for ocPDCH. This is the tracer of choice and is about 100-fold better than that for the DTA. Applied to leak certification, the LOD is about 0.00002 mL/s (0.000075 L/h), a 5 order-of-magnitude improvement over the original leak certification specification. Furthermore, this limit can be attained in a measurement period of 3 to 4 hours instead of days, weeks, or months. A new Leak Certification Facility is also proposed to provide for zonal (three zones) …
Date: March 1, 1991
Creator: Dietz, R. N. & Goodrich, R. W.
Object Type: Report
System: The UNT Digital Library
Fundamental studies of catalytic gasification (open access)

Fundamental studies of catalytic gasification

Studies of the catalytic steam gasification of carbon solids continued. A considerable number of important findings have been made. Recently limited experimentation has been carried out on the production of C{sub 2} hydrocarbons from methane in the presence of Ca/K/Ni oxide catalysts and of oxygen, carbon and water. The main finding thus far has been that C{sub 2} yields of 10--13% can be obtained at about 600{degrees}C or 150{degrees} lower temperature than described in the literature for similar yields. Yields of 7--10% C{sub 2} hydrocarbons at 99+% selectivity have been obtained. The presence of water and small amounts of oxygen is essential. Yields of this magnitude may be attractive since there is no loss of methane to valueless by-products, no purification of the recycle steam is required and no oxygen is used to burn methane. Further improvement in yields by catalyst and operating conditions modification will be investigated. It is also intended to clarify the chemistry which inhibits burning of methane to carbon oxides. Work is discussed on gasification of petroleum cokes and oxidative methane coupling. 8 figs., 2 tabs.
Date: March 1, 1991
Creator: Heinemann, H. & Somorjai, G.A.
Object Type: Report
System: The UNT Digital Library
Guidelines for Energy Simulation of Commercial Buildings: Final. (open access)

Guidelines for Energy Simulation of Commercial Buildings: Final.

This report distills the experience gained from intensive computer building simulation work for the Energy Edge project. The purpose of this report is twofold: to use that experience to guide conservation program managers in their use of modeling, and to improve the accuracy of design-phase computer models. Though the main emphasis of the report is on new commercial construction, it also addresses modeling as it pertains to retrofit construction. To achieve these purposes, this report will: (1) discuss the value of modeling for energy conservation programs; (2) discuss strengths and weaknesses of computer models; (3) provide specific guidelines for model input; (4) discuss input topics that are unusually large drivers of energy use and model inaccuracy; (5) provide guidelines for developing baseline models; (6) discuss types of energy conservation measures (ECMs) and building operation that are not suitable to modeling and present possible alternatives to modeling for analysis; and (7) provide basic requirements for model documentation. This project was initiated to determine whether commercial buildings can be designed and constructed to use at least 30% less energy than if they were designed and built to meet the current regional model energy code, the Model Conservation Standards (MCS) developed by the …
Date: March 1, 1992
Creator: Kaplan, Michael & Caner, Phoebe
Object Type: Report
System: The UNT Digital Library
PHEBUS on-line aerosol monitor development test program (open access)

PHEBUS on-line aerosol monitor development test program

EG G Idaho, Inc. developed an on-line aerosol monitor (OLAM) for the French PHEBUS Fission Product Project. Part of the development was to manufacture and test an OLAM prototype. This report presents the results of the testing which determined the mechanical integrity of the monitor at operating temperature and pressure and performed a preliminary test of the optical system. A series of twenty different tests was conducted during the prototype testing sequence. Since no leaks were detected, the OLAM demonstrated that it could provide a pressure boundary at required test conditions. The optical and electrical system also proved its integrity by exceeding the design requirement of less than 105 optical signal drift during an actual two-hour test sequence.
Date: March 1, 1992
Creator: Sprenger, M. H. & Pentecost, C. G.
Object Type: Report
System: The UNT Digital Library
High temperature catalytic membrane reactors (open access)

High temperature catalytic membrane reactors

Current state-of-the-art inorganic oxide membranes offer the potential of being modified to yield catalytic properties. The resulting modules may be configured to simultaneously induce catalytic reactions with product concentration and separation in a single processing step. Processes utilizing such catalytically active membrane reactors have the potential for dramatically increasing yield reactions which are currently limited by either thermodynamic equilibria, product inhibition, or kinetic selectivity. Examples of commercial interest include hydrogenation, dehydrogenation, partial and selective oxidation, hydrations, hydrocarbon cracking, olefin metathesis, hydroformylation, and olefin polymerization. A large portion of the most significant reactions fall into the category of high temperature, gas phase chemical and petrochemical processes. Microporous oxide membranes are well suited for these applications. A program is proposed to investigate selected model reactions of commercial interest (i.e. dehydrogenation of ethylbenzene to styrene and dehydrogenation of butane to butadiene) using a high temperature catalytic membrane reactor. Membranes will be developed, reaction dynamics characterized, and production processes developed, culminating in laboratory-scale demonstration of technical and economic feasibility. As a result, the anticipated increased yield per reactor pass economic incentives are envisioned. First, a large decrease in the temperature required to obtain high yield should be possible because of the reduced driving force …
Date: March 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Oxidation behavior of iron-chromium alloys at elevated temperatures: A reactive-element effect (open access)

Oxidation behavior of iron-chromium alloys at elevated temperatures: A reactive-element effect

Oxidation tests were conducted on samples of Fe-25Cr, Fe-25Cr,-0.3-1.0Y, and Fe-25Cr-1Ce at temperatures of 700 to 1000{degrees}C and oxygen partial pressures of 1 to 20 atm for time periods of 19 to 160 h. In some tests, oxidized samples were quenched from test temperature to room temperature in {approximately}20 min to examine characteristics of the spallation scales. The results showed that the scales, even though of the same composition, spalled totally when developed on Fe-25Cr alloy, while those on Ce- and Y-containing alloys exhibited good scale adherence and no spallation. After removal of the spalled scales, specimens of Fe-25Cr alloy were reoxidized to gain insight into development and morphology of thermally grown scales and their spallation characteristics. The reoxidized samples formed complex scale layers that had iron oxide phase at the gas side of the interface; the scale layer was adherent and no spallation was noted. Experiments were conducted to evaluate the roles of alloy grain size and grain growth rate in development and spallation of oxide scales. Results showed that excessive alloy grain growth is the primary cause of spallation of thermally grown scales. Additions of reactive elements such as Y and Ce minimize alloy grain growth and thus …
Date: March 1, 1992
Creator: Park, J. H. & Natesan, K.
Object Type: Report
System: The UNT Digital Library
Thermal energy storage technical progress report, April 1990--March 1991 (open access)

Thermal energy storage technical progress report, April 1990--March 1991

The Department of Energy (DOE) is supporting development of thermal energy storage (TES) as a means of efficiently coupling energy supplies to variable heating or cooling demands. Uses of TES include electrical demand-side management in buildings and industry, extending the utilization of renewable energy resources such as solar, and recovery of waste heat from periodic industrial processes. Technical progress to develop TES for specific diurnal and industrial applications under Oak Ridge National Laboratory's TES program from April 1990 to March 1992 is reported and covers research in the areas of low temperature sorption, direct contact ice making, latent heat storage plasterboard and latent/sensible heat regenerator technology development.
Date: March 1, 1992
Creator: Tomlinson, J.J.
Object Type: Report
System: The UNT Digital Library
Employment and land-use impacts of resource program elements (open access)

Employment and land-use impacts of resource program elements

The Pacific Northwest Laboratory (PNL) evaluated several power resource alternatives under consideration by the Bonneville Power Administration in its Resource Program Environmental Impact Statement (RPEIS). The purpose of this evaluation was to determine the potential impacts of each alternative in terms of land use and employment. We reviewed the literature that describes land-use and employment impacts to derive estimates of each type of effect. These estimates were scaled to a per-megawatt basis for use as multipliers in the RPEIS analysis. Multipliers for employment were taken from the literature and developed from power plant capital cost estimates. Land-use multipliers were taken from the literature or estimated from existing plants. In this report we compared information sources and estimates to develop the most applicable multipliers. Employment levels required (in terms of employee years per MW of plant capacity) for the construction and operation phases of each energy-generating resource alternative analyzed are shown. The amounts of land required (in terms of acres per MW capacity) for the construction and operation phases of each energy-generating resource alternatives analyzed are also shown.
Date: March 1, 1992
Creator: Shankle, S A; Baechler, M C; Blondin, D W & Grover, S E
Object Type: Report
System: The UNT Digital Library
Organization of the R chromosome region in maize (open access)

Organization of the R chromosome region in maize

The maize R gene is said to show more phenotypic variation than any other locus in higher plants. The locus is organized on a modular basis. Individual units -- termed genic elements'' since they function as independent genes -- differ by regulating the presence, intensity and timing of anthocyanin pigmentation in different plant parts. A given allele may comprise only one genic element or, more commonly, an allele comprises a complex of elements, organized as a small gene family. Different numbers and combinations of even a few genic elements gives a large number of possible complexes. Following molecular cloning of R we concentrated effort initially on a genic element that confers strong pigmentation only to the kernel. The functional limits of this gene (R-sc:124) had been defined genetically by extensive mutagenesis with the transposable element Dissociation. Subsequently, a set of contiguous probes were prepared from a genomic clone of R-sc:124. This set of probes distinguishes among various R-genic elements, providing physical evidence on gene complexes whose overall organization had been determined genetically. Some surprises were in store, as detailed below. These same tools made it possible to analyze the effect of position of Ds insertion within R-sc:124 on spotting phenotype, …
Date: March 1, 1992
Creator: Kermicle, J.
Object Type: Report
System: The UNT Digital Library
3D field harmonics (open access)

3D field harmonics

We have developed an harmonic representation for the three dimensional field components within the windings of accelerator magnets. The form by which the field is presented is suitable for interfacing with other codes that make use of the 3D field components (particle tracking and stability). The field components can be calculated with high precision and reduced cup time at any location (r,{theta},z) inside the magnet bore. The same conductor geometry which is used to simulate line currents is also used in CAD with modifications more readily available. It is our hope that the format used here for magnetic fields can be used not only as a means of delivering fields but also as a way by which beam dynamics can suggest correction to the conductor geometry. 5 refs., 70 figs.
Date: March 30, 1991
Creator: Caspi, S.; Helm, M. & Laslett, L.J.
Object Type: Report
System: The UNT Digital Library
Cost-Effectiveness of Compact Fluorescent Lighting (open access)

Cost-Effectiveness of Compact Fluorescent Lighting

Compact fluorescent technologies have been steadily improving. There has been increased interest in utilizing compact fluorescents to provide cost-effective energy savings for electric utilities in the residential sector. Several utilities in the United States have already distributed compact fluorescents to consumers free of charge. This study assesses the cost-effectiveness of compact fluorescents from the perspectives of consumers and utilities in the Pacific Northwest, where electricity rates are, on average, the lowest in the United States. The study also assesses cost-effectiveness from a societal perspective. Secondary hearing impacts and the value of reduced emissions of pollutants are incorporated into the analysis. Results indicate that compact fluorescents are more likely to be cost-effective as the perspective upon which they are assessed is broadened. Thus, they are least likely to be viewed as cost-effective by consumers, more likely to be considered cost-effective from a utility perspective, and almost always cost-effective from a societal perspective. Given these differences, is is suggested that policies be developed to capture the societal benefits of compact fluorescent retrofits through alternative regulatory or market mechanisms.
Date: March 1, 1991
Creator: Lesser, J. A. & Byers, R.
Object Type: Report
System: The UNT Digital Library
A high-power SLED 2 pulse compression system (open access)

A high-power SLED 2 pulse compression system

The enhancement of peak power by means of RF pulse compression has found important application for driving high energy electron linacs, the SLAC linac in particular. The SLAC Energy Doubler (SLED), however, yields a pulse shape in the form of a decaying exponential which limits the applicability of the method. Two methods of improving this situation have been suggested: binary pulse compression (BPC), in which the pulse is compressed by successive factors of two, and SLED II in which the pair of resonant cavities of SLED are replaced by long resonant delay lines (typically waveguides). Intermediate schemes in which the cavity pair is replaced by sequences of coupled cavities have also been considered. In this paper we describe our efforts towards the design and construction of high-power SLED II systems, which are intended to provide drivers for various advanced accelerator test facilities and potentially for the Next Linear Collider itself. The design path we have chosen requires the development of a number of microwave components in overmoded waveguide, and the bulk of this paper will be devoted to reporting our progress.
Date: March 1, 1992
Creator: Kroll, N. M.; Farkas, Z. D.; Lavine, T. L.; Menegat, A.; Ruth, R. D.; Wilson, P. B. et al.
Object Type: Article
System: The UNT Digital Library
1991 Conference summary on computing in high energy physics (open access)

1991 Conference summary on computing in high energy physics

The papers presented at the Conference cover a wide range of important issues in software engineering and management. They indicate a trend toward more use of commercial systems and standards. This trend will likely have a significant influence on plans for future systems.
Date: March 1, 1991
Creator: Loken, S.C.
Object Type: Article
System: The UNT Digital Library
The coupled dipole modes of the NLC accelerator structure (open access)

The coupled dipole modes of the NLC accelerator structure

The proposed accelerator cavity of the Next Linear Collider (NLC) is a disk-loaded structure composed of 200 cells, operating at 11.42 GHz. The proposed mode of operation is to accelerate bunches in trains of 10, with a bunch spacing of 42 cm. One problem is that one bunch in a train can excite transverse wakefields in the accelerator cavity which, in turn, can deflect following bunches and result in emittance growth. A method of curing this problem is to detune the transverse modes of the cavity. Beam dynamics simulations for the NLC have shown that by keeping the transverse wakefield at the positions of the nine trailing bunches at or below 1 MW/nC/m{sup 2} we can void emittance growth. Earlier, approximate calculations of the wakefields, which did not include the cell-to-cell coupling of the modes, have shown that by the proper Gaussian detuning the above level of cancellation can be achieved. A specific goal of this report is to see if this conclusion still holds when coupling is included in the calculation. Note that in this paper we focus on the modes belonging to the first dipole passband, which are the most important. A special feature of these modes in …
Date: March 1, 1992
Creator: Bane, K.L.F.; Gluckstern, R. & Holtkamp, N.
Object Type: Article
System: The UNT Digital Library
Development and utilization of new diagnostics for dense-phase pneumatic transport (open access)

Development and utilization of new diagnostics for dense-phase pneumatic transport

In 1988, we proposed a program to develop new diagnostics for dense gas-solid suspensions, with particular interest toward the dense pneumatic transport of cohesive solid plugs. This program included three main objectives, as follows: to develop probes for local measurements of (1) local particle volume fraction and (2) individual particle velocities in dense gas-solid flows; and (3) to construct a bench-scale setup for transporting dense cohesive solid plugs and to analyze data from the resulting tests.
Date: March 2, 1992
Creator: Louge, M. & Jenkins, J.T.
Object Type: Report
System: The UNT Digital Library
Valuation of selected environmental impacts associated with Bonneville Power Administration Resource Program alternatives (open access)

Valuation of selected environmental impacts associated with Bonneville Power Administration Resource Program alternatives

This report documents work undertaken by the Pacific Northwest Laboratory (PNL) and its contractors to assist the Bonneville Power Administration (Bonneville) in assessing the potential environmental consequences of new power resources. A major purpose of this effort is to describe and evaluate the techniques available for economic valuation of environmental costs. Another is to provide estimates of the environmental costs associated with specific power resources called for under Bonneville's Resource Programs. Bonneville's efforts to extend valuation techniques to as many impacts as can be reliably assessed represents a substantial advance in the application of state-of-the-art economic techniques to environmental assessments. This economic analysis evaluates effects on human health, wildlife, crops, and visibility impacts associated with air pollution. This report also discusses river recreation (primarily fishing) which may be affected by fluctuations in water levels. 70 refs.
Date: March 1, 1992
Creator: Englin, J E & Gygi, K F
Object Type: Report
System: The UNT Digital Library