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PRODEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP : HIGH PERFORMANCE COMPUTING WITH QCDOC AND BLUEGENE.

Description: Staff of Brookhaven National Laboratory, Columbia University, IBM and the RIKEN BNL Research Center organized a one-day workshop held on February 28, 2003 at Brookhaven to promote the following goals: (1) To explore areas other than QCD applications where the QCDOC and BlueGene/L machines can be applied to good advantage, (2) To identify areas where collaboration among the sponsoring institutions can be fruitful, and (3) To expose scientists to the emerging software architecture. This workshop grew out of an informal visit last fall by BNL staff to the IBM Thomas J. Watson Research Center that resulted in a continuing dialog among participants on issues common to these two related supercomputers. The workshop was divided into three sessions, addressing the hardware and software status of each system, prospective applications, and future directions.
Date: March 11, 2003
Creator: CHRIST,N.; DAVENPORT,J.; DENG,Y.; GARA,A.; GLIMM,J.; MAWHINNEY,R. et al.
Partner: UNT Libraries Government Documents Department

Non-existence of Normal Tokamak Equilibria with Negative Central Current

Description: Recent tokamak experiments employing off-axis, non-inductive current drive have found that a large central current hole can be produced. The current density is measured to be approximately zero in this region, though in principle there was sufficient current-drive power for the central current density to have gone significantly negative. Recent papers have used a large aspect-ratio expansion to show that normal MHD equilibria (with axisymmetric nested flux surfaces, non-singular fields, and monotonic peaked pressure profiles) can not exist with negative central current. We extend that proof here to arbitrary aspect ratio, using a variant of the virial theorem to derive a relatively simple integral constraint on the equilibrium. However, this constraint does not, by itself, exclude equilibria with non-nested flux surfaces, or equilibria with singular fields and/or hollow pressure profiles that may be spontaneously generated.
Date: February 18, 2003
Creator: Hammett, G.W.; Jardin, S.C. & Stratton, B.C.
Partner: UNT Libraries Government Documents Department

Strontium and Actinides Removal from Savannah River Site Actual Waste Samples by Freshly Precipitated Manganese Oxide

Description: The authors investigated the performance of freshly precipitated manganese oxide and monosodium titanate (MST) for the removal of strontium (Sr) and actinides from actual high-level waste. Manganese oxide precipitation occurs upon addition of a reductant such as formate (HCO2-) or peroxide (H2O2) to a waste solution containing permanganate (MnO4-). Tests described in this document address the capability of manganese oxide treatment to remove Rs, Pu, and Np from actual high-level waste containing elevated concentrations of Pu. Additionally, tests investigate MST (using two unique batches) performance with the same waste for direct comparison to the manganese oxide performance.
Date: October 30, 2003
Creator: Barnes, M.J.
Partner: UNT Libraries Government Documents Department

Development of a Novel Non-Consumable Anode for Electrowinning Primary Aluminum

Description: The principal goal of the project was to determine through theoretical considerations and from chemical and electrochemical laboratory studies the technical and economic feasibility for the substitution and retrofitting of an SOFC-type anode for today's carbon anode in a cell for electrowinning primary Al. However, solubility measurements showed that no value of cryolite ratio can exist where the solubilities of the solid electrolyte components (zirconia and especially yttria) would be small relative to the alumina solubility. Therefore, the utilization of the proposed SOFC-type anode cannot be realized for any cell involving a cryolite-base solvent. However, the project suggested that the SOFC-type anode scheme might be successful if the solvent/electrolyte for electrowinning Al could be changed to a fused sulfate melt. During the solubility experiments, electrochemical probes were developed, and a bath characterization was defined, to measure quantitatively the acid-base character of cryolite melts. The measured acid-base behavior was then used to correlate the alumina solubility in cryolite over a wide range of cryolite ratio at 1300K. A mathematical modeling of the alumina solubility as a function of basicity identified three solutes of Al{sub 2}O{sub 3} in cryolite-base melts: Na{sub 2}Al{sub 2}OF{sub 6}, Na{sub 2}Al{sub 2}O{sub 2}F{sub 4}, and Na{sub 4}Al{sub 2}O{sub 2}F{sub 6} as acidic, neutral and basic solutes, respectively. For the first time, the stereochemistry (geometries) of these complex solutes was clarified. For the non-oxygen containing Al-F complex anions, Na{sub 3}AlF{sub 6} and NaAlF{sub 4} were also considered as solutes, and some NaF (but no AlF{sub 3}) could remain in the melts. The previously suggested solute Na{sub 2}AlF{sub 5} was found to be unstable. The strong complexing in the cryolite/alumina system means that the bath is highly buffered so that a significant shift in basicity is not possible and therefore the alumina solubility does not vary greatly. The maximum ...
Date: December 4, 2003
Creator: Rapp, Robert A. & Zhang, Y.
Partner: UNT Libraries Government Documents Department

Modeling and Analysis in Support of Decision Making for Technological Investment

Description: Engineering design, resource allocation, military operations, and investment strategies share a major common trait, which is, to a large extent, independent of their different origins, specific features, and intended goals. The unifying trait is the fact that, in any of these endeavors, one has to make reasonable choices, at multiple levels of decision making, among various possible and sometimes competing prospective solutions to an important and consequential practical problem. While the specifics of the problem depend on application, context, additional constraints, etc., the ultimate--albeit imprecise--goal in all these activities is to ''optimize performance,'' which is to have maximal success/profit/return with minimal time/effort/investment. In general, the underlying system is ruled by complex and often unknown dynamics, and affected by various uncertainties, which are unknown as well; on the other hand, there are numerous levels of decision making, which result in a hierarchical structure in the decision process (tree) that is both asynchronous and non-deterministic. Usually, indifferent of the specific application, as one lowers the level of decision making, alternatives depend on fewer independent variables and models become more detailed and physics/engineering based. On the contrary, at higher levels, various components aggregate and decision making is based more on fuzzier criteria instead of readily quantifiable physics/engineering details. Moreover, decisions are strongly influenced by the educational and personal biases of the people who take them. In some instances, this may blur, if not totally obfuscate objective comparisons between various options. Therefore, a crucial point in decision-making is properly understanding and quantifying the tradeoffs, including all their future relevant consequences. Since the interaction between various choices is an intricate nonlinear process, the focus shifts from the dynamics itself to the overall performance and affordability. This is not unreasonable, since oftentimes major upgrades on some components have little impact, while minor upgrades of other components ...
Date: June 11, 2003
Creator: Lenhart, S
Partner: UNT Libraries Government Documents Department

Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

Description: Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation.
Date: February 7, 2003
Creator: Castle, James W.; Molz, Fred J.; Brame, Scott & Current, Caitlin J.
Partner: UNT Libraries Government Documents Department

Ion Chamber Compensation Tests

Description: The purpose of this report is to present the results of a series of tests performed to determine the need for gamma compensation of the ion chambers used to monitor the neutron flux in the 100 Area reactors.
Date: February 14, 2003
Creator: Mallard, R.L. Jr.
Partner: UNT Libraries Government Documents Department

Innovative Design Approaches for Large Wind Turbine Blades

Description: The primary goal of the WindPACT Blade System Design Study (BSDS) was investigation and evaluation of design and manufacturing issues for wind turbine blades in the one to ten megawatt size range. The initial project task was to assess the fundamental physical and manufacturing issues that govern and constrain large blades and entails three basic elements: (1) a parametric scaling study to assess blade structure using current technology, (2) an economic study of the cost to manufacture, transport, and install large blades, and (3) identification of promising innovative design approaches that show potential for overcoming fundamental physical and manufacturing constraints. This report discusses several innovative design approaches and their potential for blade cost reduction. During this effort we reviewed methods for optimizing the blade cross-section to improve structural and manufacturing characteristics. We also analyzed and compared a number of composite materials and evaluated their relative merits for use in large wind turbine blades in the range from 30 meters to 70 meters. The results have been summarized in dimensional and non-dimensional format to aid in interpretation. These results build upon earlier parametric and blade cost studies, which were used as a guide for the innovative design approaches explored here.
Date: March 1, 2003
Creator: ASHWILL, THOMAS D.
Partner: UNT Libraries Government Documents Department

Analysis of Events Associated with First Charge of Desicooler Material

Description: HB-Line's mission included dissolution of uranium-aluminum scrap left over from a U3O8 scrap recovery program begun in 1972 with material returned from Rocky Flats and Oak Ridge. This material has been stored in desicooler containers, and is commonly referred to as the Desicoolers. The Scrap Recovery process includes the dissolution of scrap material and transfer of the resulting solution to H-Canyon for further disposition. During the first charge of this material into the HB-Line dissolvers, the solution heated to boiling without external heat being added. Yellow-colored fumes, which dissipated rapidly, were noted in the glovebox by operators, and a small amount of liquid was noted in the glovebox by operations after dissolver cooldown. This technical report documents analysis of the data from the event with respect to potential Safety Basis violation and the Integrated Safety Management System process. Based on the analysis presented, the safety basis has shown its ability to protect the worker, the facility and the public.
Date: September 15, 2003
Creator: Alexander, D.E.
Partner: UNT Libraries Government Documents Department

Preparation of Northern Mid-Continent Petroleum Atlas

Description: This report covers the fourth year of the Digital Petroleum Atlas (DPA) Project. The DPA is a longterm effort to develop a new methodology for efficient and timely access to the latest petroleum data and technology for the domestic oil and gas industry, research organizations and local governmental units. The DPA is a new and evolving approach to generating and publishing petroleum reservoir, field, play and basin studies.
Date: February 24, 2003
Creator: Gerhard, Lee C.; Carr, Timothy R. & Watney, W. Lynn
Partner: UNT Libraries Government Documents Department

Internal/External Corrosion Analysis of the SAFKEG 3940A Package in KAMS

Description: This report describes the performance and conclusions of a 10 plus year storage mission evaluation of the potential for corrosion of the stainless steel components of the SAFKEG 3940A package in the Savannah River Site K-Area Materials Storage.
Date: December 10, 2003
Creator: Vormelker, P.R.
Partner: UNT Libraries Government Documents Department

On the Properties of Materials for Designing Filters at Optical Frequencies

Description: Frequency Selective Surfaces/Volumes (FSS/Vs), periodic structures with frequency selective properties, have widely been used for millimeter and microwave applications. Some applications include filters (band pass, band stop), reflectors, radoms etc. FSS/Vs typically consist of a single or multiple material layers. Multiple layers (with each layer having a different frequency selectivity) are used for broadband applications. In recent years there has been an interest in using these structures at optical wavelengths. One of the applications is in thermophotovoltaic filters used to convert thermal energy into electricity. The filter is designed to transmit those wavelengths that can be efficiently converted into electricity, and to reflect other spectra, which leads to energy conservation and an increase in overall system efficiency. These filters can be used in space missions to help decrease energy consumption and reduce spacecraft mass, cost, and fuel loading. Numerical simulations of such filters are very limited in the literature. Existing modeling approaches are based on the assumption of purely metallic (perfectly conducting) structures on substrates. however, in practice, metals have finite conductivity that can lead to power absorption in the metal. At optical frequencies the usual material properties and perfect electric conductor (PEC) assumption is not applicable. Moreover, the conventional methods, such as using resistive sheets or lossy dielectrics to simulate metallic losses, are not accurate. The goal is to provide a new approach for modeling metallic losses more accurately at the optical frequencies.
Date: May 5, 2003
Creator: Topsakal, E. & Volakis, J.L.
Partner: UNT Libraries Government Documents Department

A Modeling Approach for Predicting the Effect of Corrosion on Electrical-Circuit Reliability

Description: An analytical capability is being developed that can be used to predict the effect of corrosion on the performance of electrical circuits and systems. The availability of this ''toolset'' will dramatically improve our ability to influence device and circuit design, address and remediate field occurrences, and determine real limits for circuit service life. In pursuit of this objective, we have defined and adopted an iterative, statistical-based, top-down approach that will permit very formidable and real obstacles related to both the development and use of the toolset to be resolved as effectively as possible. An important component of this approach is the direct incorporation of expert opinion. Some of the complicating factors to be addressed involve the code/model complexity, the existence of large number of possible degradation processes, and an incompatibility between the length scales associated with device dimensions and the corrosion processes. Two of the key aspects of the desired predictive toolset are (1) a direct linkage of an electrical-system performance model with mechanistic-based, deterministic corrosion models, and (2) the explicit incorporation of a computational framework to quantify the effects of non-deterministic parameters (uncertainty). The selected approach and key elements of the toolset are first described in this paper. These descriptions are followed by some examples of how this toolset development process is being implemented.
Date: February 1, 2003
Creator: BRAITHWAITE, JEFFREY W.; SORENSEN, NEIL R.; ROBINSON, DAVID G.; CHEN, KEN S. & BOGDAN, CAROLYN W.
Partner: UNT Libraries Government Documents Department

Grid-based Parallel Data Streaming Implemented for the Gyrokinetic Toroidal Code

Description: We have developed a threaded parallel data streaming approach using Globus to transfer multi-terabyte simulation data from a remote supercomputer to the scientist's home analysis/visualization cluster, as the simulation executes, with negligible overhead. Data transfer experiments show that this concurrent data transfer approach is more favorable compared with writing to local disk and then transferring this data to be post-processed. The present approach is conducive to using the grid to pipeline the simulation with post-processing and visualization. We have applied this method to the Gyrokinetic Toroidal Code (GTC), a 3-dimensional particle-in-cell code used to study microturbulence in magnetic confinement fusion from first principles plasma theory.
Date: September 15, 2003
Creator: Klasky, S.; Ethier, S.; Lin, Z.; Martins, K.; McCune, D. & Samtaney, R.
Partner: UNT Libraries Government Documents Department

Kinetic Effects on the Stability Properties of Field-reversed Configurations: I. Linear Stability

Description: New computational results are presented which advance the understanding of the stability properties of the Field-Reversed Configuration (FRC). We present results of hybrid and two-fluid (Hall-MHD) simulations of prolate FRCs. The n = 1 tilt instability mechanism and growth rate reduction mechanisms are investigated in detail including resonant particle effects, finite Larmor radius and Hall stabilization, and profile effects. It is shown that the Hall effect determines the mode rotation and the change in the linear mode structure in the kinetic regime; however, the reduction in the growth rate is mostly due to finite Larmor radius effects. Resonant wave-particle interactions are studied as a function of (a) elongation, (b) the kinetic parameter S*, which is proportional to the ratio of the separatrix radius to the thermal ion Larmor radius, and (c) the separatrix shape. It is demonstrated that, contrary to the usually assumed stochasticity of the ion orbits in the FRC, a large fraction of the orbits are regular in long configurations when S* is small. A stochasticity condition is found, and a scaling with the S* parameter is presented. Resonant particle effects are shown to maintain the instability in the large gyroradius regime regardless of the separatrix shape.
Date: January 28, 2003
Creator: Belova, Elena V.; Davidson, Ronald C.; Ji, Hantao & Yamada, Masaaki
Partner: UNT Libraries Government Documents Department

Estimated Duration of the Subsurface Reducing Environment Produced by the Z-Area Saltstone Disposal Facility

Description: The formula for saltstone includes approximately 25 per cent wt slag to create a reducing environment for mitigating the subsurface transport of a number of radionuclides, including technetium-99. Based on laboratory measurements and mass balance calculations, it was estimated that the Z-Area saltstone waste form will maintain a reducing environment for more than a thousand years and likely for more than 10,000 years. The calculations were very sensitive to infiltration flow rate, underscoring the importance of the proposed moisture barrier for mitigating contaminant transport. Laboratory measurements indicated that the slag used in the formulation of the saltstone has an exceptionally high reduction capacity. Furthermore, measurements of a subsurface SRS sediment indicated that it also had a significant reduction capacity, albeit almost an order of magnitude less than that of the slag. Approximately 78 percent of the reduction capacity in the disposal system came from the saltstone, 1 4 percent from the geological materials in the overlying moisture barrier, and 9 percent from the vault made from reducing grout. This version differs from the original (WSRC-RP-2003-00362, Rev. 0) in that additional text was added to further explain the assumptions of the calculations and some typographical errors were corrected.
Date: October 3, 2003
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Rotary Burner Demonstration

Description: The subject technology, the Calcpos Rotary Burner (CRB), is a burner that is proposed to reduce energy consumption and emission levels in comparison to currently available technology. burners are used throughout industry to produce the heat that is required during the refining process. Refineries seek to minimize the use of energy in refining while still meeting EPA regulations for emissions.
Date: April 30, 2003
Creator: Flanagan, Paul
Partner: UNT Libraries Government Documents Department

Deployment of a Continuously Operated {mu}ChemLab

Description: A continuously operating prototype chemical weapons sensor system based on the {mu}ChemLab{trademark} technology was installed in the San Francisco International Airport in late June 2002. This prototype was assembled in a National Electric Manufacturers Association (NEMA) enclosure and controlled by a personal computer collocated with it. Data from the prototype was downloaded regularly and periodic calibration tests were performed through modem-operated control. The instrument was installed just downstream of the return air fans in the return air plenum of a high-use area of a boarding area. A CW Sentry, manufactured by Microsensor Systems, was installed alongside the {mu}ChemLab unit and results from its operation are reported elsewhere. Tests began on June 26, 2002 and concluded on October 16, 2002. This report will discuss the performance of the prototype during the continuous testing period. Over 70,000 test cycles were performed during this period. Data from this first field emplacement have indicated several areas where engineering improvements can be made for future field emplacement.
Date: May 1, 2003
Creator: ADKINS, DOUGLAS R.; KOTTENSTETTE, RICHARD; LEWIS, PATRICK R.; DULLECK JR., GEORGE R.; OBORNY, MICHAEL C.; GORDON, SUSANNA P. et al.
Partner: UNT Libraries Government Documents Department

Alternative HEPA Filter Full-Scale Single Element Testing

Description: Conventional disposable glass-fiber high efficiency particulate air (HEPA) filters are used throughout the Department of Energy complex in various process systems. Alternative filter media is being addressed that would have a long life on the HLW tanks.
Date: January 15, 2003
Creator: Adamson, D. J.
Partner: UNT Libraries Government Documents Department

Development of a New Technique to Assess Susceptibility to Predation Resulting from Sublethal Stresses (Indirect Mortality)

Description: Fish that pass through a hydroelectric turbine may not be killed directly, but may nonetheless experience sublethal stresses that will increase their susceptibility to predators (indirect mortality). There is a need to develop reliable tests for indirect mortality so that the full consequences of passage through turbines (and other routes around a hydroelectric dam) can be assessed. We evaluated a new technique for assessing indirect mortality, based on a behavioral response to a startling stimulus (akin to perceiving an approaching predator). We compare this technique to the standard predator preference test. The behavioral response is a rapid movement commonly referred to as a startle response, escape response, or C-shape, based on the characteristic body position assumed by the fish. When viewed from above, a startled fish bends into a C-shape, then springs back and swims away in a direction different from its original orientation. This predator avoidance (escape) behavior can be compromised by sublethal stresses that temporarily stun or disorient the fish. We subjected striped shiners and fathead minnows to varying intensities of either turbulence (10-, 20- or 30-min) or 2-min exposures to a fish anesthetic (100 or 200 mg/L of tricaine methanesulfonate), and evaluated their subsequent behavior. Individual fish were given a startle stimulus and filmed with a high-speed video camera. Each fish was startled and filmed twice before being stressed, and then at 1-, 5-, 15-, and 30-min post-exposure. The resulting image files were analyzed for a variety of behavioral measures including: presence of a response, time to first reaction, duration of reaction, time to formation of maximum C-shape, time to completion of C-shape, and completeness of C-shape. The most immediate measure of potential changes in fish behavior was whether stressed fish exhibited a startle response. For striped shiners, the number of fish not responding to the stimulus ...
Date: August 25, 2003
Creator: Cada, G.F.
Partner: UNT Libraries Government Documents Department

Effect of Dielectric Photoemission on Surface Breakdown: An LDRD Report

Description: The research discussed in this report was conceived during our earlier attempts to simulate breakdown across a dielectric surface using a Monte Carlo approach. While cataloguing the various ways that a dielectric surface could affect the breakdown process, we found that one obvious effect--photoemission from the surface--had been ignored. Initially, we felt that inclusion of this effect could have a major impact on how an ionization front propagates across a surface because of the following argument chain: (1) The photon energy required to release electrons from a surface via photoemission is less than the photon energy required to ionize gas molecules directly. (2) The mean free path of a photon in gas is longer for low-energy photons than for high-energy photons. (3) Photoionization is a major effect in advancing the ionization front for breakdown in gas without a surface, therefore, we know that even high-energy photons can be released from the head of a streamer and propagate some distance through the gas. Our hypothesis, therefore, was that photons with energies near the threshold of photoemission could travel further in front of the streamer before being absorbed than higher-energy photons needed for photoionization, yet the lower-energy photons, with the help of the surface, could still create seed electrons for new avalanches. Thus, the streamer would advance more rapidly next to a surface than in gas alone. Additionally, the photoemission from the surface would add to the electrons in the avalanche and cause the avalanche to grow faster. After some study, however, we are forced to conclude that although photoemission does contribute to avalanche growth at fields near breakdown threshold, secondary electron emission causes electrons to stick to the surface and cancels out the growth due to photoemission. This conclusion assumes a discharge that occurs over a short period of time so ...
Date: May 1, 2003
Creator: JORGENSON, ROY E.; WARNE, LARRY K.; NEUBER, ANDREAS A.; KRILE, JOHN; DICKENS, JAMES & KROMPHOLZ, HERMANN
Partner: UNT Libraries Government Documents Department

Consequences of landscape patterns on the genetic composition of remnant hardwood stands in the Southeast: A pilot study.

Description: Report of a pilot study intended to generate genetic data for a tree species in fragmented hardwood stands. It was anticipated that this data would permit assessment of the feasibility of long-term genetic research for which external funding support could be generated. A second objective was to initiate studies that addressed fundamental questions of how landscape structure, in conjunction with the population dynamics and reproductive characteristics of the tree species, influences genetic structure and long-term viability of hardwood forest stands on the Savannah River Site and in similar southeastern landscapes. Fragmentation of plant habitats can result in small, genetically isolated populations. Spatial isolation and small population size may have several consequences, including reduced reproduction, increased inbreeding and the stochastic loss of genetic variability. Such losses of genetic and genotypic diversity can reduce plant fitness and may diminish population viability. Deleterious genetic effects resulting from small population sizes can be ameliorated by gene flow via pollen and seed into fragmented populations.
Date: January 1, 2003
Creator: Godt, Mary Jo, W. & Hamrick, J., L.
Partner: UNT Libraries Government Documents Department

Autonomic Healing of Epoxy Using Micro-Encapsulated Dicyclopentadiene

Description: The autonomic healing ability of an epoxy adhesive containing micro-encapsulated dicyclopentadiene (DCPD) was evaluated. The epoxy resin used was Epon 828 cured with either Versamid 140 or diethylenetriamine (DETA). Variables included total weight percent of microcapsules (MCs) and catalyst, as well as the catalyst to DCPD ratio. The degree of healing was determined by the fracture toughness before and after ''healing'' using double-cantilever beam analysis. It was found that the degree of self-healing was most directly related to the contact area (i.e. crack width) during healing. Temperature also played a significant role. Observed differences between the results of this study and those in literature are discussed.
Date: May 1, 2003
Creator: THOMA, STEVEN G.; GIUNTA, RACHEL K.; STAVIG, MARK E.; EMERSON, JOHN A. & MORALES, ALFREDO M.
Partner: UNT Libraries Government Documents Department