Statistics for the Relative Detectability of Chemicals in Weak Gaseous Plumes in LWIR Hyperspectral Imagery (open access)

Statistics for the Relative Detectability of Chemicals in Weak Gaseous Plumes in LWIR Hyperspectral Imagery

The detection and identification of weak gaseous plumes using thermal imaging data is complicated by many factors. These include variability due to atmosphere, ground and plume temperature, and background clutter. This paper presents an analysis of one formulation of the physics-based model that describes the at-sensor observed radiance. The motivating question for the analyses performed in this paper is as follows. Given a set of backgrounds, is there a way to predict the background over which the probability of detecting a given chemical will be the highest? Two statistics were developed to address this question. These statistics incorporate data from the long-wave infrared band to predict the background over which chemical detectability will be the highest. These statistics can be computed prior to data collection. As a preliminary exploration into the predictive ability of these statistics, analyses were performed on synthetic hyperspectral images. Each image contained one chemical (either carbon tetrachloride or ammonia) spread across six distinct background types. The statistics were used to generate predictions for the background ranks. Then, the predicted ranks were compared to the empirical ranks obtained from the analyses of the synthetic images. For the simplified images under consideration, the predicted and empirical ranks showed …
Date: October 30, 2008
Creator: Metoyer, Candace N.; Walsh, Stephen J.; Tardiff, Mark F. & Chilton, Lawrence
Object Type: Report
System: The UNT Digital Library
JV Task 95-Particulate Control Consulting for Minnesota Ore Operations (open access)

JV Task 95-Particulate Control Consulting for Minnesota Ore Operations

The purpose of the project was to assist U.S. Steel in the evaluation, selection, planning, design, and testing of potential approaches to help meet U.S. Steel's goal for low-particulate matter emissions and regulatory compliance. The energy-intensive process for producing iron pellets includes treating the pellets in high-temperature kilns in which the iron is converted from magnetite to hematite. The kilns can be fired with either natural gas or a combination of gas and coal or biomass fuel and are equipped with wet venturi scrubbers for particulate control. Particulate measurements at the inlet and outlet of the scrubbers and analysis of size-fractionated particulate samples led to an understanding of the effect of process variables on the measured emissions and an approach to meet regulatory compliance.
Date: October 31, 2008
Creator: Miller, Stanley
Object Type: Text
System: The UNT Digital Library
Selected Isotopes for Optimized Fuel Assembly Tags (open access)

Selected Isotopes for Optimized Fuel Assembly Tags

In support of our ongoing signatures project we present information on 3 isotopes selected for possible application in optimized tags that could be applied to fuel assemblies to provide an objective measure of burnup. 1. Important factors for an optimized tag are compatibility with the reactor environment (corrosion resistance), low radioactive activation, at least 2 stable isotopes, moderate neutron absorption cross-section, which gives significant changes in isotope ratios over typical fuel assembly irradiation levels, and ease of measurement in the SIMS machine 2. From the candidate isotopes presented in the 3rd FY 08 Quarterly Report, the most promising appear to be Titanium, Hafnium, and Platinum. The other candidate isotopes (Iron, Tungsten, exhibited inadequate corrosion resistance and/or had neutron capture cross-sections either too high or too low for the burnup range of interest.
Date: October 1, 2008
Creator: Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J. & Hurley, David E.
Object Type: Report
System: The UNT Digital Library
Emissions, Monitoring, and Control of Mercury from Subbituminous Coal-Fired Power Plants - Phase II (open access)

Emissions, Monitoring, and Control of Mercury from Subbituminous Coal-Fired Power Plants - Phase II

Western Research Institute (WRI), in conjunction with Western Farmers Electric Cooperative (WFEC), has teamed with Clean Air Engineering of Pittsburgh PA to conduct a mercury monitoring program at the WEFC Hugo plant in Oklahoma. Sponsored by US Department of Energy Cooperative Agreement DE-FC-26-98FT40323, the program included the following members of the Subbituminous Energy Coalition (SEC) as co-sponsors: Missouri Basin Power Project; DTE Energy; Entergy; Grand River Dam Authority; and Nebraska Public Power District. This research effort had five objectives: (1) determine the mass balance of mercury for subbituminous coal-fired power plant; (2) assess the distribution of mercury species in the flue gas (3) perform a comparison of three different Hg test methods; (4) investigate the long-term (six months) mercury variability at a subbituminous coal-fired power plant; and (5) assess operation and maintenance of the Method 324 and Horiba CEMS utilizing plant personnel.
Date: October 31, 2008
Creator: Bland, Alan; Newcomer, Jesse; Kephart, Allen; Schmidt, Volker & Butcher, Gerald
Object Type: Report
System: The UNT Digital Library
Electrodic voltages in the presence of dissolved sulfide: Implications for monitoring natural microbial activity (open access)

Electrodic voltages in the presence of dissolved sulfide: Implications for monitoring natural microbial activity

There is growing interest in the development of new monitoring strategies for obtaining spatially extensive data diagnostic of microbial processes occurring in the earth. Open-circuit potentials arising from variable redox conditions in the fluid local-to-electrode surfaces (electrodic potentials) were recorded for a pair of silver-silver chloride electrodes in a column experiment, whereby a natural wetland soil containing a known community of sulfate reducers was continuously fed with a sulfate-rich nutrient medium. Measurements were made between five electrodes equally spaced along the column and a reference electrode placed on the column inflow. The presence of a sulfate reducing microbial population, coupled with observations of decreasing sulfate levels, formation of black precipitate (likely iron sulfide),elevated solid phase sulfide, and a characteristic sulfurous smell, suggest microbial-driven sulfate reduction (sulfide generation) in our column. Based on the known sensitivity of a silver electrode to dissolved sulfide concentration, we interpret the electrodic potentials approaching 700 mV recorded in this experiment as an indicator of the bisulfide (HS-) concentration gradients in the column. The measurement of the spatial and temporal variation in these electrodic potentials provides a simple and rapid method for monitoring patterns of relative HS- concentration that are indicative of the activity of sulfate-reducing …
Date: October 1, 2008
Creator: Slater, L.; Ntarlagiannis, D.; Yee, N.; O'Brien, M.; Zhang, C. & Williams, K. H.
Object Type: Article
System: The UNT Digital Library
Extracellular matrix control of mammary gland morphogenesis and tumorigenesis: insights from imaging (open access)

Extracellular matrix control of mammary gland morphogenesis and tumorigenesis: insights from imaging

The extracellular matrix (ECM), once thought to solely provide physical support to a tissue, is a key component of a cell's microenvironment responsible for directing cell fate and maintaining tissue specificity. It stands to reason, then, that changes in the ECM itself or in how signals from the ECM are presented to or interpreted by cells can disrupt tissue organization; the latter is a necessary step for malignant progression. In this review, we elaborate on this concept using the mammary gland as an example. We describe how the ECM directs mammary gland formation and function, and discuss how a cell's inability to interpret these signals - whether as a result of genetic insults or physicochemical alterations in the ECM - disorganizes the gland and promotes malignancy. By restoring context and forcing cells to properly interpret these native signals, aberrant behavior can be quelled and organization re-established. Traditional imaging approaches have been a key complement to the standard biochemical, molecular, and cell biology approaches used in these studies. Utilizing imaging modalities with enhanced spatial resolution in live tissues may uncover additional means by which the ECM regulates tissue structure, on different length scales, through its pericellular organization (short-scale) and by biasing …
Date: October 23, 2008
Creator: Ghajar, Cyrus M & Bissell, Mina J
Object Type: Article
System: The UNT Digital Library
MQ NMR and SPME analysis of nonlinearity in the degradation of a filled silicone elastomer (open access)

MQ NMR and SPME analysis of nonlinearity in the degradation of a filled silicone elastomer

Radiation induced degradation of polymeric materials occurs via numerous, simultaneous, competing chemical reactions. Though degradation is typically found to be linear in adsorbed dose, some silicone materials exhibit non-linear dose dependence due to dose dependent dominant degradation pathways. We have characterized the effects of radiative and thermal degradation on a model filled-PDMS system, Sylgard 184 (commonly used as an electronic encapsulant and in biomedical applications), using traditional mechanical testing, NMR spectroscopy, and sample headspace analysis using Solid Phase Micro-Extraction (SPME) followed by Gas Chromatography/Mass Spectrometry (GC/MS). The mechanical data and {sup 1}H spin-echo NMR indicated that radiation exposure leads to predominantly crosslinking over the cumulative dose range studies (0 to 250 kGray) with a rate roughly linear with dose. {sup 1}H Multiple Quantum NMR detected a bimodal distribution in the network structure, as expected by the proposed structure of Sylgard 184. The MQ-NMR further indicated that the radiation induced structural changes were not linear in adsorbed dose and competing chain scission mechanisms contribute more largely to the overall degradation process in the range of 50 -100 kGray (though crosslinking still dominates). The SPME-GC/MS data were analyzed using Principal Component Analysis (PCA), which identified subtle changes in the distributions of degradation …
Date: October 10, 2008
Creator: Chinn, S. C.; Alviso, C. T.; Berman, E. S.; Harvey, C. A.; Maxwell, R. S.; Wilson, T. S. et al.
Object Type: Article
System: The UNT Digital Library
QCD Corrections in Transversely Polarized Scattering (open access)

QCD Corrections in Transversely Polarized Scattering

We discuss two recent calculations of higher-order QeD corrections to scattering of transversely polarized hadrons. A basic concept underlying much of the theoretical description of high-energy hadronic scattering is the factorization theorem, which states that large momentum-transfer reactions may be factorized into long-distance pieces that contain information on the structure of the nucleon in terms of its parton densities, and parts that are short-distance and describe the hard interactions of the partons. Two crucial points are that on the one hand the long-distance contributions are universal, i.e., they are the same in any inelastic reaction under consideration, and that on the other hand the short-distance pieces depend only on the large scales related to the large momentum transfer in the overall reaction and, therefore, may be evaluated using QCD perturbation theory. The lowest order for the latter can generally only serve to give a rough description of the reaction under study. It merely captures the main features, but does not usually provide a quantitative understanding. The first-order ('next-to-leading order' (NLO)) corrections are generally indispensable in order to arrive at a firmer theoretical prediction for hadronic cross sections, and in some cases even an all-order resummation of large perturbative corrections is …
Date: October 6, 2008
Creator: Vogelsang, W.
Object Type: Article
System: The UNT Digital Library
Atmospheric Radiation Measurement program climate research facility operations quarterly report July 1 - September 30, 2008. (open access)

Atmospheric Radiation Measurement program climate research facility operations quarterly report July 1 - September 30, 2008.

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for the period July 1 - September 30, 2008, for the fixed sites. The AMF has been deployed to China, but the data have not yet been released. The fourth quarter comprises a total of 2,208 hours. The average exceeded our goal this quarter. The Site Access Request System is a web-based database used to track visitors to the fixed and mobile sites, all of which have facilities …
Date: October 8, 2008
Creator: Sisterson, D. L.
Object Type: Report
System: The UNT Digital Library
Technical Progress Report for "Optical and Electrical Properties of III-Nitrides and Related Materials" (open access)

Technical Progress Report for "Optical and Electrical Properties of III-Nitrides and Related Materials"

Investigations have been conducted focused on the fundamental material properties of AIN and high AI-content AIGaN alloys and further developed MOCVD growth technologies for obtaining these materials with improved crystalline quality and conductivities.
Date: October 31, 2008
Creator: Jiang, Hongxing
Object Type: Report
System: The UNT Digital Library
Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) into the Blast Furnace (open access)

Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) into the Blast Furnace

Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process.
Date: October 15, 2008
Creator: Zhou, Dr. Chenn
Object Type: Report
System: The UNT Digital Library
Building America Best Practices Series: Guide to Determining Climate Regions by County (open access)

Building America Best Practices Series: Guide to Determining Climate Regions by County

This document describes the eight climate region designations used by the US Department of Energy Building America Program. In addition to describing the climate zones, the document includes a complete list of every county in the United States and their climate region designations. The county lists are grouped by state. The doucment is intended to assist builders to easily identify what climate region they are building in and therefore which climate-specific Building America best practices guide would be most appropriate for them.
Date: October 1, 2008
Creator: Gilbride, Theresa L.
Object Type: Report
System: The UNT Digital Library
Modelin the Transport and Chemical Evolution of Onshore and Offshore Emissions and Their Impact on Local and Regional Air Quality Using a Variable-Grid-Resolution Air Quality Model (open access)

Modelin the Transport and Chemical Evolution of Onshore and Offshore Emissions and Their Impact on Local and Regional Air Quality Using a Variable-Grid-Resolution Air Quality Model

The overall objective of this research project was to develop an innovative modeling technique to adequately model the offshore/onshore transport of pollutants. The variable-grid modeling approach that was developed alleviates many of the shortcomings of the traditionally used nested regular-grid modeling approach, in particular related to biases near boundaries and the excessive computational requirements when using nested grids. The Gulf of Mexico region contiguous to the Houston-Galveston area and southern Louisiana was chosen as a test bed for the variable-grid modeling approach. In addition to the onshore high pollution emissions from various sources in those areas, emissions from on-shore and off-shore oil and gas exploration and production are additional sources of air pollution. We identified case studies for which to perform meteorological and air quality model simulations. Our approach included developing and evaluating the meteorological, emissions, and chemistry-transport modeling components for the variable-grid applications, with special focus on the geographic areas where the finest grid resolution was used. We evaluated the performance of two atmospheric boundary layer (ABL) schemes, and identified the best-performing scheme for simulating mesoscale circulations for different grid resolutions. Use of a newly developed surface data assimilation scheme resulted in improved meteorological model simulations. We also successfully …
Date: October 16, 2008
Creator: Hanna, Adel
Object Type: Report
System: The UNT Digital Library
A CW normal-conductive RF gun for free electron laser and energy recovery linac applications (open access)

A CW normal-conductive RF gun for free electron laser and energy recovery linac applications

Currently proposed energy recovery linac and high average power free electron laser projects require electron beam sources that can generate up to {approx} 1 nC bunch charges with less than 1 mmmrad normalized emittance at high repetition rates (greater than {approx} 1 MHz). Proposed sources are based around either high voltage DC or microwave RF guns, each with its particular set of technological limits and system complications. We propose an approach for a gun fully based on mature RF and mechanical technology that greatly diminishes many of such complications. The concepts for such a source as well as the present RF and mechanical design are described. Simulations that demonstrate the beam quality preservation and transport capability of an injector scheme based on such a gun are also presented.
Date: October 8, 2008
Creator: Baptiste, Kenneth; Corlett, John; Kwiatkowski, Slawomir; Lidia, Steven; Qiang, Ji; Sannibale, Fernando et al.
Object Type: Article
System: The UNT Digital Library
AFM CHARACTERIZATION OF RAMAN LASER INDUCED DAMAGE ON CDZNTECRYSTAL SURFACES (open access)

AFM CHARACTERIZATION OF RAMAN LASER INDUCED DAMAGE ON CDZNTECRYSTAL SURFACES

High quality CdZnTe (or CZT) crystals have the potential for use in room temperature gamma-ray and X-ray spectrometers. Over the last decade, the methods for growing high quality CZT have improved the quality of the produced crystals however there are material features that can influence the performance of these materials as radiation detectors. The presence of structural heterogeneities within the crystals, such as twinning, pipes, grain boundaries (polycrystallinity), and secondary phases (SPs) can have an impact on the detector performance. There is considerable need for reliable and reproducible characterization methods for the measurement of crystal quality. With improvements in material characterization and synthesis, these crystals may become suitable for widespread use in gamma radiation detection. Characterization techniques currently utilized to test for quality and/or to predict performance of the crystal as a gamma-ray detector include infrared (IR) transmission imaging, synchrotron X-ray topography, photoluminescence spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Raman spectroscopy. In some cases, damage caused by characterization methods can have deleterious effects on the crystal performance. The availability of non-destructive analysis techniques is essential to validate a crystal's quality and its ability to be used for either qualitative or quantitative gamma-ray or X-ray detection. The …
Date: October 7, 2008
Creator: Teague, L. & Duff, M.
Object Type: Article
System: The UNT Digital Library
Thermal Neutron Detectors with Discrete Anode Pad Readout (open access)

Thermal Neutron Detectors with Discrete Anode Pad Readout

A new two-dimensional thermal neutron detector concept that is capable of very high rates is being developed. It is based on neutron conversion in {sup 3}He in an ionization chamber (unity gas gain) that uses only a cathode and anode plane; there is no additional electrode such as a Frisch grid. The cathode is simply the entrance window, and the anode plane is composed of discrete pads, each with their own readout electronics implemented via application specific integrated circuits. The aim is to provide a new generation of detectors with key characteristics that are superior to existing techniques, such as higher count rate capability, better stability, lower sensitivity to background radiation, and more flexible geometries. Such capabilities will improve the performance of neutron scattering instruments at major neutron user facilities. In this paper, we report on progress with the development of a prototype device that has 48 x 48 anode pads and a sensitive area of 24cm x 24cm.
Date: October 19, 2008
Creator: Yu,B. & Schaknowski, N.A., Smith, G.C., DeGeronimo, G., Vernon, E.O.
Object Type: Article
System: The UNT Digital Library
The Integrity of ACSR Full Tension Single-Stage Splice Connector at Higher Operation Temperature (open access)

The Integrity of ACSR Full Tension Single-Stage Splice Connector at Higher Operation Temperature

Due to increases in power demand and limited investment in new infrastructure, existing overhead power transmission lines often need to operate at temperatures higher than those used for the original design criteria. This has led to the accelerated aging and degradation of splice connectors. It is manifested by the formation of hot-spots that have been revealed by infrared imaging during inspection. The implications of connector aging is two-fold: (1) significant increases in resistivity of the splice connector (i.e., less efficient transmission of electricity) and (2) significant reductions in the connector clamping strength, which could ultimately result in separation of the power transmission line at the joint. Therefore, the splice connector appears to be the weakest link in electric power transmission lines. This report presents a protocol for integrating analytical and experimental approaches to evaluate the integrity of full tension single-stage splice connector assemblies and the associated effective lifetime at high operating temperature.
Date: October 1, 2008
Creator: Wang, Jy-An John; Lara-Curzio, Edgar & King, Thomas J., Jr.
Object Type: Report
System: The UNT Digital Library
Interim Letter Report - Verification Survey of 19 Grids in the Lester Flat Area, David Witherspoon Inc. 1630 Site Knoxville, Tennessee (open access)

Interim Letter Report - Verification Survey of 19 Grids in the Lester Flat Area, David Witherspoon Inc. 1630 Site Knoxville, Tennessee

Perform verification surveys of 19 available grids located in the Lester Flat Area at the Davod Witherspoon Site. The survey grids included E11, E12, E13, F11, F12, F13, F14, F15, G15, G16, G17, H16, H17, H18, X16, X17, X18, K16, and J16.
Date: October 17, 2008
Creator: Weaver, P. C.
Object Type: Report
System: The UNT Digital Library
COMPENDIUM: SURVEYS EVALUATING KNOWLEDGE AND OPINIONS CONCERNING HYDROGEN AND FUEL CELL TECHNOLOGIES (open access)

COMPENDIUM: SURVEYS EVALUATING KNOWLEDGE AND OPINIONS CONCERNING HYDROGEN AND FUEL CELL TECHNOLOGIES

This compendium updates a 2003 literature review of surveys of knowledge and opinions of hydrogen and fuel cell technologies. Its purpose is to ensure that results of comparable surveys are considered in surveys conducted by the U.S. Department of Energy (DOE). Over twice as many studies related to the DOE survey have been published since 2003 than prior to that date. The fact that there have been significantly more studies implies that there have been further demonstration projects and/or increased interest in hydrogen and fuel cell technologies. The primary findings of these 15 new surveys, all of which were conducted in Europe (E) or North America (NA), to the DOE surveys are as follows: 1.Respondents who are more educated are more accepting of hydrogen technologies (NA). 2.Respondents who are more knowledgeable about hydrogen and/or fuel cells are more accepting of hydrogen technologies (E, NA). 3.When asked about issues of trust, respondents generally expressed distrust of the government or political parties but trusted scientists and environmental protection organizations (E). 4.Technical knowledge about hydrogen and fuel cell technologies is low (E, NA). 5.Respondents may express opinions about a technology even when they are lacking in knowledge of that technology (E). 6.Women and …
Date: October 1, 2008
Creator: Truett, Lorena Faith; Cooper, Christy & Schmoyer, Richard L
Object Type: Report
System: The UNT Digital Library
Human performance modeling for system of systems analytics. (open access)

Human performance modeling for system of systems analytics.

A Laboratory-Directed Research and Development project was initiated in 2005 to investigate Human Performance Modeling in a System of Systems analytic environment. SAND2006-6569 and SAND2006-7911 document interim results from this effort; this report documents the final results. The problem is difficult because of the number of humans involved in a System of Systems environment and the generally poorly defined nature of the tasks that each human must perform. A two-pronged strategy was followed: one prong was to develop human models using a probability-based method similar to that first developed for relatively well-understood probability based performance modeling; another prong was to investigate more state-of-art human cognition models. The probability-based modeling resulted in a comprehensive addition of human-modeling capability to the existing SoSAT computer program. The cognitive modeling resulted in an increased understanding of what is necessary to incorporate cognition-based models to a System of Systems analytic environment.
Date: October 1, 2008
Creator: Dixon, Kevin R.; Lawton, Craig R.; Basilico, Justin Derrick; Longsine, Dennis E. (INTERA, Inc., Austin, TX); Forsythe, James Chris; Gauthier, John Henry et al.
Object Type: Report
System: The UNT Digital Library
Grays River Watershed Restoration Status Report 2007, May 1, 2007 - October 30, 2008. (open access)

Grays River Watershed Restoration Status Report 2007, May 1, 2007 - October 30, 2008.

The Bonneville Power Administration (BPA) Project 2003-013-00, 'Grays River Watershed Restoration', began in FY04 and continues into FY09. This status report is intended to summarize accomplishments during the period 1 May 2007 through 30 October 2008. Accomplishments are summarized by Work Elements, as detailed in the Statement of Work (see BPA's project management database PISCES). The Pacific Northwest National Laboratory (PNNL) is collaborating with the Columbia River Estuary Task Force (CREST) on implementation of the Grays River Restoration Project. The Grays River is vitally important to the recovery of Lower Columbia River (LCR) chum salmon because it currently has the most viable population remaining in the LCR region. The Grays River watershed is also important to the recovery of salmon and steelhead in the LCR ecosystem. Today, numbers of naturally spawning salmon and steelhead have declined to levels far below historical numbers because of habitat limiting factors that include but are not limited to the lack of habitat connectivity, diversity, channel stability, riparian function and altered stream flow conditions. The objective of this project is to restore habitat-forming processes to enhance salmon and steelhead populations in the Grays River, following recommendations developed during the FY04-06 BPA-sponsored Grays River Watershed Assessment …
Date: October 20, 2008
Creator: Hanrahan, Tim
Object Type: Report
System: The UNT Digital Library
Physical Sciences Facility Air Emission Control Equivalency Evaluation (open access)

Physical Sciences Facility Air Emission Control Equivalency Evaluation

This document presents the adequacy evaluation for the application of technology standards during design, fabrication, installation and testing of radioactive air exhaust systems at the Physical Sciences Facility (PSF), located on the Horn Rapids Triangle north of the Pacific Northwest National Laboratory (PNNL) complex. The analysis specifically covers the exhaust portion of the heating, ventilation and air conditioning (HVAC) systems associated with emission units EP-3410-01-S, EP-3420-01-S and EP 3430-01-S.
Date: October 17, 2008
Creator: Brown, David M. & Belew, Shan T.
Object Type: Report
System: The UNT Digital Library
Industrial Compositional Streamline Simulation for Efficient and Accurate Prediction of Gas Injection and WAG Processes (open access)

Industrial Compositional Streamline Simulation for Efficient and Accurate Prediction of Gas Injection and WAG Processes

Gas-injection processes are widely and increasingly used for enhanced oil recovery (EOR). In the United States, for example, EOR production by gas injection accounts for approximately 45% of total EOR production and has tripled since 1986. The understanding of the multiphase, multicomponent flow taking place in any displacement process is essential for successful design of gas-injection projects. Due to complex reservoir geometry, reservoir fluid properties and phase behavior, the design of accurate and efficient numerical simulations for the multiphase, multicomponent flow governing these processes is nontrivial. In this work, we developed, implemented and tested a streamline based solver for gas injection processes that is computationally very attractive: as compared to traditional Eulerian solvers in use by industry it computes solutions with a computational speed orders of magnitude higher and a comparable accuracy provided that cross-flow effects do not dominate. We contributed to the development of compositional streamline solvers in three significant ways: improvement of the overall framework allowing improved streamline coverage and partial streamline tracing, amongst others; parallelization of the streamline code, which significantly improves wall clock time; and development of new compositional solvers that can be implemented along streamlines as well as in existing Eulerian codes used by industry. …
Date: October 31, 2008
Creator: Gerritsen, Margot
Object Type: Report
System: The UNT Digital Library
Modeling Protein Structures with Conditional Random Fields: Final Report (open access)

Modeling Protein Structures with Conditional Random Fields: Final Report

This document is the final report for DE-FG02-05ER25696. It describes the results of the performed research.
Date: October 28, 2008
Creator: Langmead, Christopher
Object Type: Report
System: The UNT Digital Library