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Registered Apprenticeship Programs: Labor Can Better Use Data to Target Oversight (open access)

Registered Apprenticeship Programs: Labor Can Better Use Data to Target Oversight

A letter report issued by the Government Accountability Office with an abstract that begins "Between 2002 and 2012 nearly 850,000 jobs will open in the construction industry; experts predict that there will not be enough skilled workers to fill them. This has heightened concerns about program outcomes and program quality in the nation's apprenticeship system and the U.S. Department of Labor's oversight of it. GAO assessed (1) the extent to which Labor monitors registered apprenticeship programs in the states where it has direct oversight, (2) its oversight activities in states that do their own monitoring, and (3) the outcomes for construction apprentices in programs sponsored by employers and unions in relation to programs sponsored by employers alone."
Date: August 29, 2005
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Nuclear Nonproliferation: Better Management Controls Needed for Some DOE Projects in Russia and Other Countries (open access)

Nuclear Nonproliferation: Better Management Controls Needed for Some DOE Projects in Russia and Other Countries

A letter report issued by the Government Accountability Office with an abstract that begins "The National Defense Authorization Act for FY 2004 mandated that we assess the management of threat reduction and nonproliferation programs that the Departments of Defense and Energy each administer. The objective of this report is to assess how the Department of Energy's National Nuclear Security Administration (NNSA) implements management controls, which we define here to be the processes ensuring that work done under a contract meets contract specifications and that payments go to contractors as intended."
Date: August 29, 2005
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
X-Ray CT of Highly-Attenuating Objects: 9- or 15- MV Spectra? (open access)

X-Ray CT of Highly-Attenuating Objects: 9- or 15- MV Spectra?

We imaged-highly attenuating test objects in three dimensions with 9-MV (at LLNL) and 15-MV (at Hill Air Force Base) x-ray spectra. While we used the same detector and motion control, there were differences that we could not control in the two radiography bays and in the sources. The results show better spatial resolution for the 9-MV spectrum and better contrast for the 15-MV spectrum. The 15-MV data contains a noise pattern that obfuscates the data. It is our judgment that if sufficient attention were given to design of the bay, beam dump, collimation, filtration and linac spot size; a 15-MV imaging system using a flat panel could be developed with spatial resolution of 5 lp/mm and contrastive performance better than we have demonstrated using a 9-MV spectrum.
Date: August 29, 2005
Creator: Stone, G; Trebes, J; Perry, R; Schneberk, D & Logan, C
System: The UNT Digital Library
ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT (open access)

ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT

The purpose of this model report is to describe the evolution of the physical and chemical environmental conditions within the waste emplacement drifts of the repository, including the drip shield and waste package surfaces. The resulting seepage evaporation and gas abstraction models are used in the total system performance assessment for the license application (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. This report develops and documents a set of abstraction-level models that describe the engineered barrier system physical and chemical environment. Where possible, these models use information directly from other reports as input, which promotes integration among process models used for TSPA-LA. Specific tasks and activities of modeling the physical and chemical environment are included in ''Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration'' (BSC 2005 [DIRS 173782], Section 1.2.2). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system reports. To be consistent with other project documents that address features, events, and processes (FEPs), Table 6.14.1 of the current report includes updates to FEP numbers and FEP subjects for two FEPs identified in the technical …
Date: August 29, 2005
Creator: Jarek, R.
System: The UNT Digital Library
Water Imbibition into Rock as Affected by Sample Shape, Pore, Conductivity, and Antecedent Water Content (open access)

Water Imbibition into Rock as Affected by Sample Shape, Pore, Conductivity, and Antecedent Water Content

Infiltration is often presumed to follow Philip's equation, I = st{sup 1/2}, where I is cumulative infiltration, s is sorptivity, and t is time. This form of the equation is appropriate for short times, and/or for negligible gravitational effects. For a uniform soil, this equation describes a plot of log(mass imbibed) versus log(time), with a slope (imbibition exponent) of 1/2. The equation has also been applied to low-porosity rocks, where the extremely small pores render gravitational forces negligible. Experiments recently performed on a wide variety of rocks produced imbibition exponents from 0.2 to 0.5. Many rock types showed initial imbibition proceeding as I {approx} t{sup 1/4}, then later switched to ''normal'' (t{sup 1/2}) behavior. The distance to the wetting front that corresponds to this cross-over behavior was found to be related to the sample shape: tall thin samples are more likely to exhibit the exponent 1/4, and to cross over to 1/2-type behavior later, while short, squat samples are less likely to display the 1/4-type behavior at all. Additionally, the exponents are sensitive to antecedent water content, with initially wetter samples having smaller values. In this study, we present the experimental data, and provide a consistent and physically-based explanation using …
Date: August 29, 2005
Creator: Ewing, R.P.
System: The UNT Digital Library
21-PWR Waste Package Side and End Impacts (open access)

21-PWR Waste Package Side and End Impacts

The objective of this calculation is to determine the structural response of a 21-Pressurized Water Reactor (PWR) spent nuclear fuel waste package impacting an unyielding surface. A range of initial velocities and initial angles between the waste package and the unyielding surface is studied. The scope of this calculation is limited to estimating the area of the outer shell (OS) where the residual stress exceeds a given limit (hereafter ''damaged area''). The stress limit is defined as a fraction of the yield strength of the OS material, Alloy 22 (SB-575 N06022), at the appropriate temperature. The design of the 21-PWR waste package used in this calculation is that defined in Reference 8. However, a value of 4 mm was used for the gap between the inner shell and the OS, and the thickness of the OS was reduced by 2 mm. The sketch in Attachment I provides additional information not included in Reference 8. All obtained results are valid for this design only. This calculation is associated with the waste package design and was performed by the Specialty Analyses and Waste Package Design Section. The waste package (i.e. uncanistered spent nuclear fuel disposal container) is classified as Quality Level 1.
Date: August 29, 2005
Creator: Schmitt, T.
System: The UNT Digital Library
Seismic Consequence Abstraction (open access)

Seismic Consequence Abstraction

None
Date: August 29, 2005
Creator: C., Quittmeyer R.
System: The UNT Digital Library
Investigation of Accelerated Casing Corrosion in Two Wells at Waste Management Area A-AX (open access)

Investigation of Accelerated Casing Corrosion in Two Wells at Waste Management Area A-AX

The sidewall core samples from well 299-E24-19, which were comprised of a mixture of bentonite and silt lens material, had an average porewater chloride concentration of 376 mg/L. The sidewall core samples collected from well 299-E25-46 had calculated porewater chloride concentrations ranging from 1,200 to more than 10,000 mg/L. Clearly, the sidewall core samples tested were capable of generating porewaters with sufficient chloride concentrations to cause corrosion of the stainless steel well casing. Furthermore, analysis of the sidewall core samples yielded a clear relationship between chloride concentration and well casing corrosion. The sidewall core samples containing the greatest amount of chloride, 3000 {micro}g/g of sediment, came from the well that experienced the longest length of casing failure (4.2 feet in well 299-E25-46). All of the sidewall core samples tested from both decommissioned wells contained more chloride than the Wyoming bentonite test material. However, since chloride was present as a trace constituent in all of the sidewall core samples (less than 0.4 weight percent), it is possible that it could have been introduced to the system as a ''contaminant'' contained in the bentonite backfill material. Therefore, it is likely that chloride leached from the bentonite material and/or chloride carried by/as a …
Date: August 29, 2005
Creator: Brown, Christopher F.; Serne, R JEFFREY.; Schaef, Herbert T.; Williams, Bruce A.; Valenta, Michelle M.; LeGore, Virginia L. et al.
System: The UNT Digital Library
Horizontal Heat Exchanger Design and Analysis for Passive Heat Removal Systems (open access)

Horizontal Heat Exchanger Design and Analysis for Passive Heat Removal Systems

This report describes a three-year project to investigate the major factors of horizontal heat exchanger performance in passive containment heat removal from a light water reactor following a design basis accident LOCA (Loss of Coolant Accident). The heat exchanger studied in this work may be used in advanced and innovative reactors, in which passive heat removal systems are adopted to improve safety and reliability The application of horizontal tube-bundle condensers to passive containment heat removal is new. In order to show the feasibility of horizontal heat exchangers for passive containment cooling, the following aspects were investigated: 1. the condensation heat transfer characteristics when the incoming fluid contains noncondensable gases 2. the effectiveness of condensate draining in the horizontal orientation 3. the conditions that may lead to unstable condenser operation or highly degraded performance 4. multi-tube behavior with the associated secondary-side effects This project consisted of two experimental investigations and analytical model development for incorporation into industry safety codes such as TRAC and RELAP. A physical understanding of the flow and heat transfer phenomena was obtained and reflected in the analysis models. Two gradute students (one funded by the program) and seven undergraduate students obtained research experience as a part of …
Date: August 29, 2005
Creator: Vierow, Karen
System: The UNT Digital Library
ASH REDISTRIBUTION FOLLOWING A POTENTIAL VOLCANIC ERUPTION AT YUCCA MOUNTAIN (open access)

ASH REDISTRIBUTION FOLLOWING A POTENTIAL VOLCANIC ERUPTION AT YUCCA MOUNTAIN

The redistribution of contaminated tephra by hillslope, fluvial, and pedologic processes is a poorly-constrained but important aspect of evaluating the radiological dose from an unlikely volcanic eruption at Yucca Mountain (YM). To better evaluate this hazard, we developed a spatially distributed, numerical model of tephra redistribution that integrates contaminated tephra from hill slopes and active channels, mixes it with clean sediment in the channel system, distributes it on the fan, and migrates it into the soil column. The model is coupled with an atmospheric dispersion model that predicts the deposition of radioactive waste-contaminated tephra at specified grid points. The redistribution model begins in the upper Fortymile Wash drainage basin where it integrates the tephra deposited on steep slopes and active channel beds within a GIS framework. The Fortymile Wash drainage basin is the focus of this model because tephra from only this basin reaches the Fortymile Wash alluvial fan by fluvial processes, and it is on this fan where the radiological dose to a hypothetical individual is compared to the regulatory standard (via additional biosphere models). The dilution effect of flood scour, mixing, and re-deposition within the upper basin is modeled using a dilution-mixing model widely used in the contaminant-transport …
Date: August 29, 2005
Creator: Pelletier, J.; deLong, S.; Cline, M.L.; Harrington, C. & Keating, G.
System: The UNT Digital Library
Numerical Studies of Magnetohydrodynamic Activity Resulting from Inductive Transients Final Report (open access)

Numerical Studies of Magnetohydrodynamic Activity Resulting from Inductive Transients Final Report

This report describes results from numerical studies of transients in magnetically confined plasmas. The work has been performed by University of Wisconsin graduate students James Reynolds and Giovanni Cone and by the Principal Investigator through support from contract DE-FG02-02ER54687, a Junior Faculty in Plasma Science award from the DOE Office of Science. Results from the computations have added significantly to our knowledge of magnetized plasma relaxation in the reversed-field pinch (RFP) and spheromak. In particular, they have distinguished relaxation activity expected in sustained configurations from transient effects that can persist over a significant fraction of the plasma discharge. We have also developed the numerical capability for studying electrostatic current injection in the spherical torus (ST). These configurations are being investigated as plasma confinement schemes in the international effort to achieve controlled thermonuclear fusion for environmentally benign energy production. Our numerical computations have been performed with the NIMROD code (http://nimrodteam.org) using local computing resources and massively parallel computing hardware at the National Energy Research Scientific Computing Center. Direct comparisons of simulation results for the spheromak with laboratory measurements verify the effectiveness of our numerical approach. The comparisons have been published in refereed journal articles by this group and by collaborators at …
Date: August 29, 2005
Creator: Sovinec, Carl R.
System: The UNT Digital Library
New Regenerative Cycle for Vapor Compression Refrigeration (open access)

New Regenerative Cycle for Vapor Compression Refrigeration

The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic …
Date: August 29, 2005
Creator: Bergander, Mark J.
System: The UNT Digital Library
Magma Dynamics at Yucca Mountain, Nevada (open access)

Magma Dynamics at Yucca Mountain, Nevada

Small-volume basaltic volcanic activity at Yucca Mountain has been identified as one of the potential events that could lead to release of radioactive material from the U.S. Department of Energy (DOE) designated nuclear waste repository at Yucca Mountain. Release of material could occur indirectly as a result of magmatic dike intrusion into the repository (with no associated surface eruption) by changing groundwater flow paths, or as a result of an eruption (dike intrusion of the repository drifts, followed by surface eruption of contaminated ash) or volcanic ejection of material onto the Earth's surface and the redistribution of contaminated volcanic tephra. Either release method includes interaction between emplacement drifts and a magmatic dike or conduit, and natural (geologic) processes that might interrupt or halt igneous activity. This analysis provides summary information on two approaches to evaluate effects of disruption at the repository by basaltic igneous activity: (1) descriptions of the physical geometry of ascending basaltic dikes and their interaction with silicic host rocks similar in composition to the repository host rocks; and (2) a summary of calculations developed to quantify the response of emplacement drifts that have been flooded with magma and repressurized following blockage of an eruptive conduit. The purpose …
Date: August 29, 2005
Creator: Krier, D.
System: The UNT Digital Library
The Government's Long-Term Fiscal Shortfall: How Much Is Attributable to Social Security? (open access)

The Government's Long-Term Fiscal Shortfall: How Much Is Attributable to Social Security?

This report discusses social security in the context of the federal budget. One rationale given for Social Security reform is the large long-term fiscal shortfall that Social Security is projected to face.
Date: August 29, 2005
Creator: Labonte, Marc
System: The UNT Digital Library
Fishery, Aquaculture, and Marine Mammal Legislation in the 109th Congress (open access)

Fishery, Aquaculture, and Marine Mammal Legislation in the 109th Congress

Fish and marine mammals are important resources in open ocean and nearshore coastal areas. Many laws and regulations guide the management of these resources by federal agencies. This report contains information on commercial and sport fisheries, aquaculture, and marine mammals and issues related to the 109th Congress.
Date: August 29, 2005
Creator: Buck, Eugene H.
System: The UNT Digital Library
Pesticide Use and Water Quality: Are the Laws Complementary or in Conflict? (open access)

Pesticide Use and Water Quality: Are the Laws Complementary or in Conflict?

None
Date: August 29, 2005
Creator: unknown
System: The UNT Digital Library
The Endangered Species Act (ESA) in the 109th Congress: Conflicting Values and Difficult Choices (open access)

The Endangered Species Act (ESA) in the 109th Congress: Conflicting Values and Difficult Choices

None
Date: August 29, 2005
Creator: Buck, Eugene H.; Corn, M. Lynne; Sheikh, Pervaze A.; Baldwin, Pamela & Meltz, Robert
System: The UNT Digital Library
Strategic Petroleum Reserve (open access)

Strategic Petroleum Reserve

This report includes information regarding strategic petroleum reserve. Background and analysis, purchases of crude oil, and drawdown of the reserve are among topics discussed in this report.
Date: August 29, 2005
Creator: Bamberger, Robert
System: The UNT Digital Library
China and Sub-Saharan Africa (open access)

China and Sub-Saharan Africa

This report provides information about the China and Sub-Saharan Africa where china has been involved in sub-Saharan Africa .china-Africa trade is growing and chinese firms are engaged in large projects.
Date: August 29, 2005
Creator: Copson, Raymond W. & Dumbaugh, Kerry
System: The UNT Digital Library
Nevada Work Instruction Laboratory Dynamic Rock/Soil Testing (open access)

Nevada Work Instruction Laboratory Dynamic Rock/Soil Testing

This procedure defines processes for performance and reporting of geotechnical laboratory tests supporting geotechnical investigations.
Date: August 29, 2005
Creator: Schweppe, M. & Scotese, T.R.
System: The UNT Digital Library
Production of Arrayed and Rearrayed cDNA Libraries for Public Use (open access)

Production of Arrayed and Rearrayed cDNA Libraries for Public Use

Researchers studying genes and their protein products need an easily available source for that gene. The I.M.A.G.E. Consortium at Lawrence Livermore National Laboratory is an important source of such genes in the form of arrayed cDNA libraries. The arrayed clones and associated data are available to the public, free of restriction. Libraries are transformed and titered into 384-well master plates, from which 2-8 copies are made. One copy plate is stored by LLNL while others are sent to sequencing groups, plate distributors, and to the group which contributed the library. Clones found to be unique and/or full-length are rearrayed and also made publicly available. Bioinformatics tools supporting the use of I.M.A.G.E. clones are accessible via the World Wide Web.
Date: August 29, 2005
Creator: Rasmussen, K
System: The UNT Digital Library
Dry Transfer Facility Seismic Analysis (open access)

Dry Transfer Facility Seismic Analysis

None
Date: August 29, 2005
Creator: Mulkey, T.
System: The UNT Digital Library
Navy-Marine Corps Tactical Air Integration Plan: Background and Issues for Congress (open access)

Navy-Marine Corps Tactical Air Integration Plan: Background and Issues for Congress

None
Date: August 29, 2005
Creator: Bolkcom, Christopher & O'Rourke, Ronald
System: The UNT Digital Library
A High Power Beam-On-Target Test of Liquid Lithium Target for RIA. (open access)

A High Power Beam-On-Target Test of Liquid Lithium Target for RIA.

Experiments were conducted to demonstrate the stable operation of a windowless liquid lithium target under extreme thermal loads that are equivalent to uranium beams from the proposed Rare Isotope Accelerator (RIA) driver linac. The engineering and safety issues accompanying liquid lithium systems are first discussed. The liquid metal technology knowledge base generated primarily for fast reactors, and liquid metal cooled fusion reactors, was applied to the development of these systems in a nuclear physics laboratory setting. The use of a high energy electron beam for simulating a high power uranium beam produced by the RIA driver linac is also described. Calculations were performed to obtain energy deposition profiles produced by electron beams at up to a few MeV to compare with expected uranium beam energy deposition profiles. It was concluded that an experimental simulation using a 1-MeV electron beam would be a valuable tool to assess beam-jet interaction. In the experiments, the cross section of the windowless liquid lithium target was 5 mm x 10 mm, which is a 1/3rd scale prototype target, and the velocity of the liquid lithium was varied up to 6 m/s. Thermal loads up to 20 kW within a beam spot diameter of 1mm were …
Date: August 29, 2005
Creator: Nolen, J.; Reed, C.; Novick, V.; Specht, J.; Plotkin, P.; Momozaki,Y. et al.
System: The UNT Digital Library