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Modeling and Simulation of Long-Term Performance of Near-Surface Barriers

Description: Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surfa… more
Date: February 1, 2003
Creator: Piet, Steven James; Jacobson, Jacob Jordan; Soto, Rafael; Martian, Pete & Martineau, Richard Charles
Partner: UNT Libraries Government Documents Department
open access

Making Sustainable Decisions Using the KONVERGENCE Framework

Description: Hundreds of contaminated facilities and sites must be cleaned up. “Cleanup” includes decommissioning, environmental restoration, and waste management. Cleanup can be complex, expensive, risky, and time-consuming. Decisions are often controversial, can stall or be blocked, and are sometimes re-done - some before implementation, some decades later. Making and keeping decisions with long time horizons involves special difficulties and requires new approaches, including: • New ways (mental model) t… more
Date: February 1, 2003
Creator: Piet, Steven James; Gibson, Patrick Lavern; Joe, Jeffrey Clark; Kerr, Thomas A; Nitschke, Robert Leon & Dakins, Maxine Ellen
Partner: UNT Libraries Government Documents Department
open access

Equilibrium in heavy ion collisions

Description: We discuss the question of equilibration in heavy ion collisions and how it can be addressed in experiment.
Date: February 1, 2003
Creator: Koch, Volker & Majumder, Abhijit
Partner: UNT Libraries Government Documents Department
open access

Testing, Modeling, and Monitoring to Enable Simpler, Cheaper, Longer-Lived Surface Caps

Description: Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent downward water migration. Some of the hazards will … more
Date: February 1, 2003
Creator: Piet, Steven James; Breckenridge, Robert Paul & Burns, Douglas Edward
Partner: UNT Libraries Government Documents Department
open access

Exciton dynamicsstudied via internal THz transitions

Description: We employ a novel, ultrafast terahertz probe to investigatethe dynamical interplay of optically-induced excitons and unboundelectron-hole pairs in GaAs quantum wells. Resonant creation ofheavy-hole excitons induces a new low-energy oscillator linked totransitions between the internal exciton degrees of freedom. The timeresolved terahertz optical conductivity is found to be a probe wellsuited for studies of fundamental processes such as formation, relaxationand ionization of excitons.
Date: February 26, 2003
Creator: Kaindl, R. A.; Hagele, D.; Carnahan, M. A.; Lovenich, R. & Chemla, D. S.
Partner: UNT Libraries Government Documents Department
open access

'Mini'-Roadmapping - Ensuring Timely Sites' Cleanup / Closure by Resolving Science and Technology Issues

Description: Roadmapping is a powerful tool to manage technical risks and opportunities associated with complex problems. Roadmapping identifies technical capabilities required for both project- and program-level efforts and provides the basis for plans that ensure the necessary enabling activities will be done when needed. Roadmapping reveals where to focus further development of the path forward by evaluating uncertainties for levels of complexity, impacts, and/or the potential for large payback. Roadmaps… more
Date: February 1, 2003
Creator: Luke, Dale & Murphy, James
Partner: UNT Libraries Government Documents Department
open access

A Source-to-Source Architecture for User-Defined Optimizations

Description: The performance of object-oriented applications often suffers from the inefficient use of high-level abstractions provided by underlying libraries. Since these library abstractions are user-defined and not part of the programming language itself only limited information on their high-level semantics can be leveraged through program analysis by the compiler and thus most often no appropriate high-level optimizations are performed. In this paper we outline an approach based on source-to-source tr… more
Date: February 6, 2003
Creator: Schordan, M & Quinlan, D
Partner: UNT Libraries Government Documents Department
open access

Inversion of Synthetic Aperture Radar Interferograms for Sources of Production-Related Subsidence at the Dixie Valley Geothermal Field

Description: We used synthetic aperture radar interferograms to image ground subsidence that occurred over the Dixie Valley geothermal field during different time intervals between 1992 and 1997. Linear elastic inversion of the subsidence that occurred between April, 1996 and March, 1997 revealed that the dominant sources of deformation during this time period were large changes in fluid volumes at shallow depths within the valley fill above the reservoir. The distributions of subsidence and subsurface volu… more
Date: February 7, 2003
Creator: Foxall, W & Vasco, D
Partner: UNT Libraries Government Documents Department
open access

12th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Summary Discussion Sessions

Description: This report is a summary of the discussion sessions of the 12th Workshop on Crystalline Silicon Solar Cells and Processes. The theme of the workshop was"Fundamental R&D in c-Si: Enabling Progress in Solar-Electric Technology." This theme was chosen to reflect a concern that the current expansion in the PV energy production may redirect basic research efforts to production-oriented issues. The PV industry is installing added production capacity and new production lines that include the latest te… more
Date: February 1, 2003
Creator: Sopori, B.; Swanson, D.; Sinton, R. & Tan, T.
Partner: UNT Libraries Government Documents Department
open access

Out-of-Core Compression and Decompression of Large n-Dimensional Scalar Fields

Description: We present a simple method for compressing very large and regularly sampled scalar fields. Our method is particularly attractive when the entire data set does not fit in memory and when the sampling rate is high relative to the feature size of the scalar field in all dimensions. Although we report results for R{sup 3} and R{sup 4} data sets, the proposed approach may be applied to higher dimensions. The method is based on the new Lorenzo predictor, introduced here, which estimates the value of … more
Date: February 3, 2003
Creator: Ibarria, L.; Lindstrom, P.; Rossignac, J. & Szymczak, A.
Partner: UNT Libraries Government Documents Department
open access

Coulomb Energy, Vortices, and Confinement

Description: d on 25 Feb 2003 (v1), last revised 10 Apr 2003 (this version, v2))We estimate the Coulomb energy of static quarks from a Monte Carlo calculation of the correlator of timelike link variables in Coulomb gauge. We find, in agreement with Cucchieri and Zwanziger, that this energy grows linearly with distance at large quark separations. The corresponding string tension, however, is several times greater than the accepted asymptotic string tension, indicating that a state containing only static sour… more
Date: February 25, 2003
Creator: Greensite, J. & Olejnik, S.
Partner: UNT Libraries Government Documents Department
open access

Explicit Supersymmetry Breaking on Boundaries of Warped Extra Dimensions

Description: Explicit supersymmetry breaking is studied in higher dimensional theories by having boundaries respect only a subgroup of the bulk symmetry. If the boundary symmetry is the maximal subgroup allowed by the boundary conditions imposed on the fields, then the symmetry can be consistently gauged; otherwise gauging leads to an inconsistent theory. In a warped fifth dimension, an explicit breaking of all bulk supersymmetries by the boundaries is found to be inconsistent with gauging; unlike the case … more
Date: February 25, 2003
Creator: Hall, Lawrence J.; Nomura, Yasunori; Okui, Takemichi & Oliver, Steven J.
Partner: UNT Libraries Government Documents Department
open access

Contamination Control During In Situ Jet Grouting for Application in a Buried Transuranic Waste Site

Description: Engineers at the Idaho National Engineering and Environmental Laboratory (INEEL) have developed means of contamination control associated with jet-grouting buried radioactive mixed waste sites. Finely divided plutonium/americium oxide particulate can escape as the drill stem of the jet-grouting apparatus exits a waste deposit in preparation for insertion in another injection hole. In studying various options for controlling this potential contamination, engineers found that an elaborate glovebo… more
Date: February 1, 2003
Creator: Loomis, Guy George & Jessmore, James Joseph
Partner: UNT Libraries Government Documents Department
open access

Hydrogen Gas Generation Model for Fuel Based Remote Handled TRU Waste Stored at INEEL

Description: The Idaho National Environmental and Engineering Laboratory (INEEL) initiated efforts to calculate the hydrogen gas generation in remote-handled transuranic (RH-TRU) containers in order to evaluate continued storage of unvented RH-TRU containers in vaults and to identify any potential problems during retrieval and aboveground storage. A computer code is developed to calculate the hydrogen concentration in the stored RH-TRU waste drums for known configuration, waste matrix, and radionuclide inve… more
Date: February 1, 2003
Creator: Khericha, Soli T.; Bhatt, Rajiv N. & Liekhus, Kevin
Partner: UNT Libraries Government Documents Department
open access

Radiological Characterization Methodology of INEEL Stored RH-TRU Waste from ANL-E

Description: An Acceptable Knowledge (AK)-based radiological characterization methodology is being developed for RH TRU waste generated from ANL-E hot cell operations performed on fuel elements irradiated in the EBR-II reactor. The methodology relies on AK for composition of the fresh fuel elements, their irradiation history, and the waste generation and collection processes. Radiological characterization of the waste involves the estimates of the quantities of significant fission products and transuranic i… more
Date: February 1, 2003
Creator: Bhatt, Rajiv N.
Partner: UNT Libraries Government Documents Department
open access

Microtopography for Ductile Fracture Process Characterization - Part 1: Theory and Methodology

Description: The mechanics of ductile fracture is receiving increased focus as the importance of integrity of structures constructed from ductile materials is increasing. The non-linear, irreversible mechanical response of ductile materials makes generalized models of ductile cracking very difficult to develop. Therefore, research and testing of ductile fracture have taken a path leading to deformation-based parameters such as crack tip opening displacement (CTOD) and crack tip opening angle (CTOA). Constra… more
Date: February 1, 2003
Creator: Lloyd, Wilson Randolph
Partner: UNT Libraries Government Documents Department
open access

INEEL Lead Recycling in a Moratorium Environment

Description: Since 1999, the Idaho National Engineering and Environmental Laboratory (INEEL) Lead Project successfully recycled over 700,000 pounds of excess INEEL lead to the private sector. On February 14, 2000, the Secretary of Energy, Bill Richardson, formalized the January 12, 2000, moratorium on recycling radioactive scrap metal that prevented the unrestricted release of recycled scrap metals to the private sector. This moratorium created significant problems for the INEEL lead recycling program and a… more
Date: February 1, 2003
Creator: Kooda, Kevin Evan; Mc Cray, Casey William; Aitken, Darren William & Galloway, Kelly
Partner: UNT Libraries Government Documents Department
open access

Digging for Treasure - Unique Fate and Transport Study

Description: In 1970, scientists at the National Bureau of Standards (NBS), now called the National Institute of Standards and Testing (NIST), implemented the most ambitious and comprehensive long-term corrosion behavior test for stainless steels in soil environments. This study had historic significance since the NBS 1957 landmark corrosion textbook compiled by Romanoff did not include stainless steels, and this 1970 research set forth to complete the missing body of knowledge. To conduct the test, NIST sc… more
Date: February 1, 2003
Creator: Zirker, Larry; Adler-Flitton, M. K. & Beitel, G. A.
Partner: UNT Libraries Government Documents Department
open access

Real-Time Soils Characterization and Analyses Systems Used at Ohio Closure Sites

Description: The Idaho National Engineering and Environmental Laboratory (INEEL) and the Fernald Environmental Management Project (FEMP) have jointly developed a field-deployed analytical system to rapidly scan, characterize, and analyze surface soil contamination. The basic system consists of a sodium iodide (NaI) spectrometer and global positioning system (GPS) hardware. This hardware can be deployed from any of four different platforms depending on the scope of the survey at hand. These platforms range f… more
Date: February 1, 2003
Creator: Roybal, Lyle Gene; Carpenter, Michael Vance; Giles, John Robert; Hartwell, John Kelvin & Danahy, R.
Partner: UNT Libraries Government Documents Department
open access

Microtopography for Ductile Fracture Process Characterization - Part 2: Application for CTOA Analysis

Description: The crack tip opening angle (CTOA) is seeing increased use to characterize fracture in so-called "low constraint" geometries, such as thin sheet aerospace structures and thin-walled pipes. With this increase in application comes a need to more fully understand and measure actual CTOA behavior. CTOA is a measure of the material response during ductile fracture, a "crack tip response function". In some range of crack extension following growth initiation, a constant value of CTOA is often assumed… more
Date: February 1, 2003
Creator: Lloyd, Wilson Randolph & McClintock, F. A.
Partner: UNT Libraries Government Documents Department
open access

Finding Text Information in the Ocean of Electronic Documents

Description: Information management in natural resources has become an overwhelming task. A massive amount of electronic documents and data is now available for creating informed decisions. The problem is finding the relevant information to support the decision-making process. Determining gaps in knowledge in order to propose new studies or to determine which proposals to fund for maximum potential is a time-consuming and difficult task. Additionally, available data stores are increasing in complexity; they… more
Date: February 5, 2003
Creator: Medvick, Patricia A. & Calapristi, Augustin J.
Partner: UNT Libraries Government Documents Department
open access

An in situ transmission electron microscopy study of the thermalstability of near-surface microstructures induced by deep rolling andlaser-shock peening

Description: Mechanical surface treatments are known to be effective at improving the fatigue resistance of metallic alloys at elevated temperatures ({approx}550-600 C), even though the near-surface compressive residual stress fields have been annealed out. We have investigated the thermal stability of near-surface microstructures induced by deep rolling and laser-shock peening in an austentic stainless steel (AISI 304) and a titanium alloy (Ti-6Al-4V) using in situ hot-stage transmission electron microscop… more
Date: February 24, 2003
Creator: Altenberger, I.; Stach, E. A.; Liu, G. Y.; Nalla, R. K. & Ritchie, R. O.
Partner: UNT Libraries Government Documents Department
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