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Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $454.75 reconciled for the period ending on July 14, 2001.
Date: July 14, 2001
Creator: unknown
System: The UNT Digital Library
Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $1,247.07 reconciled for the period ending on June 28, 2002.
Date: July 14, 2002
Creator: unknown
System: The UNT Digital Library
Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $454.75 reconciled for the period ending on July 14, 2001.
Date: July 14, 2001
Creator: unknown
System: The UNT Digital Library
Investigation into the Role of Initial Conditions on Rayleigh-Taylor Instabilities by Low Atwood Experiments and Simulations (open access)

Investigation into the Role of Initial Conditions on Rayleigh-Taylor Instabilities by Low Atwood Experiments and Simulations

The primary goal of the research being conducted this summer is to investigate the role of initial conditions in the development of a two fluid mix driven by Rayleigh-Taylor instability. The effects of initial conditions will be studied through the use of experimental facilities located at the Buoyancy-Driven Mixing Lab at Texas A&M University and through high resolution direct numerical simulations of the experiment by the MIRANDA code developed at Lawrence Livermore National Lab. The Experimental Objectives are: (1) Analyze the early time development of a two fluid Rayleigh-Taylor driven mix between two miscible fluids at low Atwood numbers. (2) Quantify the initial conditions of the unstably stratified fluids by means of statistical mixing parameters and spectral analysis of the centerline density fluctuations. (3) Capture PLIF images of initial development of the flow for use in simulation setup. (Wayne Kraft) (4) Determine exactly what component of the experimental mixing data (position downstream from the splitter plate) most accurately represents the initial conditions of the experiment. The Simulation Objectives are: (1) Perform two dimensional and three dimensional simulations of the experimental setup. Analyze the results of these simulations for comparison to the experimental results. (2) Various methods of implementing the initial …
Date: July 14, 2003
Creator: Mueschke, N; Andrews, M & Schilling, O
System: The UNT Digital Library
Circuit Model for Gun Driven Spheromaks (open access)

Circuit Model for Gun Driven Spheromaks

In this note we derive circuit equations for sustained spheromaks, in the phase after a spheromak is detached from the gun and sustained in a flux conserver. The impedance of the spheromak during the formation and ''bubble burst'' phase has been discussed by Barnes et. al. We assume here that the spheromak is formed and helicity is being delivered to it from the gun, currents are above the threshold current, and the {lambda}-gradients are outward ({lambda} decreasing inward). We follow an open field line that begins and ends at the gun electrodes, encircling the closed flux surfaces of the spheromak, and apply power and helicity balance equations for this gun-driven system. In addition to these equations one will need to know the initial conditions (currents, stored energies) after the ''bubble burst'' in order to project forward in time.
Date: July 14, 2000
Creator: Thomassen, K I
System: The UNT Digital Library
Cloud Occurrence Frequency at the Barrow, Alaska, ARM Climate Research Facility for 2008 Third Quarter 2009 ARM and Climate Change Prediction Program Metric Report (open access)

Cloud Occurrence Frequency at the Barrow, Alaska, ARM Climate Research Facility for 2008 Third Quarter 2009 ARM and Climate Change Prediction Program Metric Report

Clouds represent a critical component of the Earth’s atmospheric energy balance as a result of their interactions with solar and terrestrial radiation and a redistribution of heat through convective processes and latent heating. Despite their importance, clouds and the processes that control their development, evolution and lifecycle remain poorly understood. Consequently, the simulation of clouds and their associated feedbacks is a primary source of inter-model differences in equilibrium climate sensitivity. An important step in improving the representation of cloud process simulations is an improved high-resolution observational data set of the cloud systems including their time evolution. The first order quantity needed to understand the important role of clouds is the height of cloud occurrence and how it changes as a function of time. To this end, the Atmospheric Radiation Measurement (ARM) Climate Research Facilities (ACRF) suite of instrumentation has been developed to make the observations required to improve the representation of cloud systems in atmospheric models.
Date: July 14, 2009
Creator: Jensen, M; Johnson, K & Mather, JH
System: The UNT Digital Library
Temperature and Water Depth Monitoring Within Chum Salmon Spawning Habitat Below Bonneville Dam -- Annual Report -- October 2007-September 2008 (open access)

Temperature and Water Depth Monitoring Within Chum Salmon Spawning Habitat Below Bonneville Dam -- Annual Report -- October 2007-September 2008

The overall goal of the project described in this report is to provide a sound scientific basis for operation of the Federal Columbia River Power System (FCRPS) in ways that will effectively protect and enhance chum salmon populations----a species listed in March 1999 as threatened under the Endangered Species Act of 1973 (ESA). The study objective during fiscal year 2008 was to provide real-time data on Ives Island area water temperature and water surface elevations from the onset of chum salmon spawning through the end of chum salmon emergence. Sampling locations included areas where riverbed temperatures were elevated, potentially influencing alevin development and emergence timing. In these locations, hydrosystem operation caused large, frequent changes in river discharge that affected salmon habitat by dewatering redds and altering egg pocket temperatures. The 2008 objective was accomplished using temperature and water-level sensors deployed inside piezo¬meters. Sensors were integrated with a radio telemetry system such that real-time data could be downloaded remotely and posted hourly on the Internet.
Date: July 14, 2009
Creator: Arntzen, Evan V.
System: The UNT Digital Library
Temperature and Water Depth Monitoring Within Chum Salmon Spawning Habitat Below Bonneville Dam : Annual Report October 2007-September 2008 (open access)

Temperature and Water Depth Monitoring Within Chum Salmon Spawning Habitat Below Bonneville Dam : Annual Report October 2007-September 2008

The overall goal of the project described in this report is to provide a sound scientific basis for operation of the Federal Columbia River Power System (FCRPS) in ways that will effectively protect and enhance chum salmon populations - a species listed in March 1999 as threatened under the Endangered Species Act of 1973 (ESA). The study objective during fiscal year 2008 was to provide real-time data on Ives Island area water temperature and water surface elevations from the onset of chum salmon spawning through the end of chum salmon emergence. Sampling locations included areas where riverbed temperatures were elevated, potentially influencing alevin development and emergence timing. In these locations, hydrosystem operation caused large, frequent changes in river discharge that affected salmon habitat by dewatering redds and altering egg pocket temperatures. The 2008 objective was accomplished using temperature and water-level sensors deployed inside piezometers. Sensors were integrated with a radio telemetry system such that real-time data could be downloaded remotely and posted hourly on the Internet. During our overall monitoring period (October 2007 through June 2008), mean temperature in chum spawning areas was nearly 2 C warmer within the riverbed than in the overlying river. During chum salmon spawning (mid-November …
Date: July 14, 2009
Creator: Arntzen, E.V.
System: The UNT Digital Library
An Engineering Approach to Laboratory Ergonomics (open access)

An Engineering Approach to Laboratory Ergonomics

None
Date: July 14, 2009
Creator: Pollard, Martin J.
System: The UNT Digital Library
Atmospheric Radiation Measurement program climate research facilities quarterly report April 1 - June 30, 2009. (open access)

Atmospheric Radiation Measurement program climate research facilities quarterly report April 1 - June 30, 2009.

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 approximately 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. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,074.80 hours (0.95 x 2,184 hours this quarter); for the North Slope Alaska (NSA) locale it is 1,965.60 hours …
Date: July 14, 2009
Creator: Sisterson, D. L.
System: The UNT Digital Library
A Multi-Layer Phoswich Radioxenon Detection System (open access)

A Multi-Layer Phoswich Radioxenon Detection System

Laboratory radioactive sources were used to characterize the phoswich detector. The CaF{sub 2} scintillator has a low light-yield and slow decay time, thus produces very small signals due to low-energy gamma rays or X-rays. Therefore, detection of 30 keV X-rays (from the xenon radioisotopes) using this layer and discriminating its very small signals from electronic noise was a challenging task. Several solutions were considered and experimentally evaluated. We found that the best solution would be extending the fast triangular filter from 10 taps to 30 taps. This will extend the peaking time of this filter from 25 nsec to 75 nsec. The digital filter is implemented in FPGA on our DPP2.0 and is used to trigger the detection system. Functionality of the new filter in capturing and discriminating 30 keV X-rays was confirmed by using a {sup 133}Ba gamma-ray source. Development of the DPP GUI software has continued with the addition of two new panels to display histograms of beta/gamma and beta/x-ray coincidence events. This includes coincidence events from a single channel, as well as two-channel, coincidence event. A pileup rejection algorithm has been implemented in the FPGA code, and controls to adjust its sensitivity have been added to the …
Date: July 14, 2008
Creator: Hamby, David M.
System: The UNT Digital Library
Snake River Sockeye Salmon Habitat and Limnological Research: 2005 Annual Report. (open access)

Snake River Sockeye Salmon Habitat and Limnological Research: 2005 Annual Report.

In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list Snake River sockeye salmon (Oncorhynchus nerka) as endangered. Snake River sockeye salmon were officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Project was implemented. This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of Snake River sockeye salmon. The Shoshone-Bannock Tribal goal for this project is two tiered: The immediate goal is to increase the population of Snake River sockeye salmon while preserving the unique genetic characteristics of the Evolutionarily Significant Unit (ESU). The Tribes long term goal is to maintain a viable population that warrants delisting and provides Tribal harvest opportunities. The Bonneville Power Administration (BPA) provides funding for this interagency recovery. Collaborators in the recovery effort include the National Oceanic and Atmospheric Administration (NOAA), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), and the Shoshone-Bannock Tribes (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2005 calendar year. Project tasks include: (1) monitor limnological parameters of the …
Date: July 14, 2006
Creator: Taki, Doug; Kohler, Andre E.; Griswold, Robert G. & Gilliland, Kim
System: The UNT Digital Library
New Group Contribution and Equation of State Models for Improved Engineering Practice (open access)

New Group Contribution and Equation of State Models for Improved Engineering Practice

As this was the final year of the research contract, most of the activities centered on completing some of the research in progress, and an orderly transition to other activities. Overall, the recent years of the project have been successful as evidenced by the accomplishments listed below and the papers published between 2005 and the present, as well as their impact and the cooperation they have encouraged with people qt other universities and industry.
Date: July 14, 2008
Creator: Sandler, Stanley I.
System: The UNT Digital Library
A Strong-Lens Survey in AEGIS: the Influence of Large Scale Structure (open access)

A Strong-Lens Survey in AEGIS: the Influence of Large Scale Structure

We report on the results of a visual search for galaxy-scale strong gravitational lenses over 650 arcmin2 of HST/ACS imaging in the Extended Groth Strip (EGS). These deep F606W- and F814W-band observations are in the DEEP2-EGS field. In addition to a previously-known Einstein Cross also found by our search (the ''Cross'', HSTJ141735+52264, with z{sub lens} = 0.8106 and a published z{sub source} = 3.40), we identify two new strong galaxy-galaxy lenses with multiple extended arcs. The first, HSTJ141820+52361 (the ''Dewdrop''; z{sub lens} = 0.5798), lenses two distinct extended sources into two pairs of arcs (z{sub source} = 0.9818 by nebular [O{sub II}] emission), while the second, HSTJ141833+52435 (the ''Anchor''; z{sub lens} = 0.4625), produces a single pair of arcs (source redshift not yet known). Four less convincing arc/counter-arc and two-image lens candidates are also found and presented for completeness. All three definite lenses are fit reasonably well by simple singular isothermal ellipsoid models including external shear, giving {chi}{sub {nu}}{sup 2}values close to unity. Using the three-dimensional line-of-sight (LOS) information on galaxies from the DEEP2 data, we calculate the convergence and shear contributions {kappa}{sub los} and {gamma}{sub los} to each lens, assuming singular isothermal sphere halos truncated at 200 h{sup -1} …
Date: July 14, 2006
Creator: Moustakas, Leonidas A.; Marshall, Phil J.; Newman, Jeffrey A.; Coil, Alison L.; Cooper, Michael C.; Davis, Marc et al.
System: The UNT Digital Library
Luminosity Function of Faint Globular Clusters in M87 (open access)

Luminosity Function of Faint Globular Clusters in M87

We present the luminosity function to very faint magnitudes for the globular clusters in M87, based on a 30 orbit Hubble Space Telescope (HST) WFPC2 imaging program. The very deep images and corresponding improved false source rejection allow us to probe the mass function further beyond the turnover than has been done before. We compare our luminosity function to those that have been observed in the past, and confirm the similarity of the turnover luminosity between M87 and the Milky Way. We also find with high statistical significance that the M87 luminosity function is broader than that of the Milky Way. We discuss how determining the mass function of the cluster system to low masses can constrain theoretical models of the dynamical evolution of globular cluster systems. Our mass function is consistent with the dependence of mass loss on the initial cluster mass given by classical evaporation, and somewhat inconsistent with newer proposals that have a shallower mass dependence. In addition, the rate of mass loss is consistent with standard evaporation models, and not with the much higher rates proposed by some recent studies of very young cluster systems. We also find that the mass-size relation has very little slope, …
Date: July 14, 2006
Creator: Waters, Christopher Z.; Zepf, Stephen E.; U., /Michigan State; Lauer, Tod R.; /NOAO, Tucson; Baltz, Edward A. et al.
System: The UNT Digital Library
IN-PACKAGE CHEMISTRY ABSTRACTION (open access)

IN-PACKAGE CHEMISTRY ABSTRACTION

This report was developed in accordance with the requirements in ''Technical Work Plan for Postclosure Waste Form Modeling'' (BSC 2005 [DIRS 173246]). The purpose of the in-package chemistry model is to predict the bulk chemistry inside of a breached waste package and to provide simplified expressions of that chemistry as a function of time after breach to Total Systems Performance Assessment for the License Application (TSPA-LA). The scope of this report is to describe the development and validation of the in-package chemistry model. The in-package model is a combination of two models, a batch reactor model, which uses the EQ3/6 geochemistry-modeling tool, and a surface complexation model, which is applied to the results of the batch reactor model. The batch reactor model considers chemical interactions of water with the waste package materials, and the waste form for commercial spent nuclear fuel (CSNF) waste packages and codisposed (CDSP) waste packages containing high-level waste glass (HLWG) and DOE spent fuel. The surface complexation model includes the impact of fluid-surface interactions (i.e., surface complexation) on the resulting fluid composition. The model examines two types of water influx: (1) the condensation of water vapor diffusing into the waste package, and (2) seepage water entering …
Date: July 14, 2005
Creator: Thomas, E.
System: The UNT Digital Library
EBS Radionuclide Transport Abstraction (open access)

EBS Radionuclide Transport Abstraction

The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that …
Date: July 14, 2006
Creator: Prouty, J.
System: The UNT Digital Library
Collaborating for Multi-Scale Chemical Science (open access)

Collaborating for Multi-Scale Chemical Science

Advanced model reduction methods were developed and integrated into the CMCS multiscale chemical science simulation software. The new technologies were used to simulate HCCI engines and burner flames with exceptional fidelity.
Date: July 14, 2006
Creator: Green, William H.
System: The UNT Digital Library
Neutralizing Carbonic Acid in Deep Carbonate Strata below the North Atlantic (open access)

Neutralizing Carbonic Acid in Deep Carbonate Strata below the North Atlantic

Our research is aimed at investigating several technical issues associated with carbon dioxide sequestration in calcium carbonate sediments below the sea floor through laboratory experiments and chemical transport modeling. Our goal is to evaluate the basic feasibility of this approach, including an assessment of optimal depths, sediment types, and other issues related to site selection. The results of our modeling efforts were published this past summer in the Proceedings of the National Academy of Sciences. We are expanding on that work through a variety of laboratory and modeling efforts. In the laboratories at Columbia and at Harvard, we are studying the flow of liquid carbon dioxide and carbon dioxide-water mixtures through calcium carbonate sediments to better understand the geomechanical and structural stability of the sediments during and after injection. We are currently preparing the results of these findings for publication. In addition, we are investigating the kinetics of calcium carbonate dissolution in the presence of CO{sub 2}-water fluids, which is a critical feature of the system as it allows for increased permeability during injection. We are also investigating the possibility of carbon dioxide hydrate formation in the pore fluid, which might complicate the injection procedure by reducing sediment permeability but …
Date: July 14, 2006
Creator: Schrag, Daniel P.
System: The UNT Digital Library
Field Test Program for Long-Term Operation of a COHPAC System for Removing Mercury from Coal-Fired Flue Gas (open access)

Field Test Program for Long-Term Operation of a COHPAC System for Removing Mercury from Coal-Fired Flue Gas

With the Nation's coal-burning utilities facing the possibility of tighter controls on mercury pollutants, the U.S. Department of Energy is funding projects that could offer power plant operators better ways to reduce these emissions at much lower costs. Sorbent injection technology represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. It involves injecting a solid material such as powdered activated carbon into the flue gas. The gas-phase mercury in the flue gas contacts the sorbent and attaches to its surface. The sorbent with the mercury attached is then collected by the existing particle control device along with the other solid material, primarily fly ash. During 2001, ADA Environmental Solutions (ADA-ES) conducted a full-scale demonstration of sorbent-based mercury control technology at the Alabama Power E.C. Gaston Station (Wilsonville, Alabama). This unit burns a low-sulfur bituminous coal and uses a hot-side electrostatic precipitator (ESP) in combination with a Compact Hybrid Particulate Collector (COHPAC{reg_sign}) baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC{reg_sign} baghouse. Activated carbon was injected between the ESP and COHPAC{reg_sign} units to collect the mercury. Short-term mercury removal …
Date: July 14, 2005
Creator: Bustard, Jean; Lindsey, Charles; Brignac, Paul; Starns, Travis; Sjostrom, Sharon & Larson, Cindy
System: The UNT Digital Library
Environmental Protection Department Operations and Regulatory Affairs Division Contingency Plan for Site 300 Waste Accumulation Area(s) (open access)

Environmental Protection Department Operations and Regulatory Affairs Division Contingency Plan for Site 300 Waste Accumulation Area(s)

This Contingency Plan identifies personnel responsibilities, emergency equipment, and required actions necessary to mitigate potential incidents at the Waste Accumulation Area(s) (WAA)(s) located at the Lawrence Livermore National Laboratory (LLNL) Experimental Test Site 300 (Site 300) as shown in Figure 1. This Plan is designed to prepare personnel to minimize hazards to human health and the environment from fires, explosions, or any sudden or nonsudden release of hazardous, radioactive, or mixed waste constituents to the air, ground surface, or water from waste stored in the WAA(s). The LLNL Site 300 currently has one WAA. The location of the WAA is shown in Figure 2 and identified in Table 1. As programmatic needs change, it may become necessary to establish additional WAAs at Site 300. The WAA is a small, regularly monitored storage area where waste can be accumulated and stored temporarily. Hazardous and mixed waste can be stored or accumulated in a WAA for up to 90 days, after which it must be transferred to a Department of Toxic Substances Control (DTSC) authorized onsite treatment or storage facility or an authorized offsite treatment, storage, or disposal facility (TSDF). The onsite TSDFs authorized by DTSC are managed by the Radioactive and …
Date: July 14, 2005
Creator: Levy, R
System: The UNT Digital Library
Mechanisms of Plastic and Fracture Instabilities for Alloy Development of Fusion Materials. Final Project Report for period July 15, 1998 - July 14, 2003 (open access)

Mechanisms of Plastic and Fracture Instabilities for Alloy Development of Fusion Materials. Final Project Report for period July 15, 1998 - July 14, 2003

The main objective of this research was to develop new computational tools for the simulation and analysis of plasticity and fracture mechanisms of fusion materials, and to assist in planning and assessment of corresponding radiation experiments.
Date: July 14, 2003
Creator: Ghoniem, N. M.
System: The UNT Digital Library
Corridor One: An Integrated Distance Visualization Environment for SSI and ASCI Applications (open access)

Corridor One: An Integrated Distance Visualization Environment for SSI and ASCI Applications

Scenarios describe realistic uses of DVC/Distance technologies in several years. Four scenarios are described: Distributed Decision Making; Remote Interactive Computing; Remote Visualization: (a) Remote Immersive Visualization and (b) Remote Scientific Visualization; Remote Virtual Prototyping. Scenarios serve as drivers for the road maps and enable us to check that the functionality and technology in the road maps match application needs. There are four major DVC/Distance technology areas we cover: Networking and QoS; Remote Computing; Remote Visualization; Remote Data. Each “road map” consists of two parts, a “functionality” matrix (what can be done) and a “technology” matrix (underlying technology). That is, functionality matrices show the desired operational characteristics, while technology matrices show the underlying technology needed. In practice, there isn’t always a clean break between “functionality” and “technology,” but it still seems useful to try and separate things this way.
Date: July 14, 2002
Creator: Rick Stevens (ANL, PI) & Jason Leigh (UIC, PI)
System: The UNT Digital Library