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A Fusion Chamber for the 2002 Robust Point Design (open access)

A Fusion Chamber for the 2002 Robust Point Design

A top-level overview of the mechanical design for the 2002 Robust Point Design (RPD-2002) fusion chamber is introduced. It is based on the HYLIFE-II design and includes modifications to the liquid pocket configuration and first structural wall (FSW), facilitates periodic maintenance or replacement of internal components, and is compliant with all other RPD-2002 parameters. This work has been carried out by constructing a parametric computer model capable of being updated as future changes become necessary.
Date: October 1, 2003
Creator: Abbott, R P
Object Type: Article
System: The UNT Digital Library
Effects of Light Scalar Mesons in eta -> 3pi decay (open access)

Effects of Light Scalar Mesons in eta -> 3pi decay

We study the role of a possible nonet of light scalar mesons in the still interesting [eta] -> 3[p]i decay process, with the primary motivation of learning more about the scalars themselves. The framework is a conventional non-linear chiral Lagrangian of pseudoscalars and vectors extended to include the scalars. The parameters involving the scalars were previously obtained to fit the s-wave [pi][pi] and [pi] K scatterings in the region up to about 1 GeV as well as the strong decay [eta]' --> [eta][pi][pi]. At first, one might expect a large enhancement from diagrams including a light [sigma] (560). However there is an amusing cancellation mechanism which prevents this from occurring. In the simplest model there is an enhancement of about 13 per cent in the [eta] -> 3[pi] decay rate due to the scalars. In a more complicated model which includes derivative type symmetry breakers, the cancellation is modified and the scalars contribute about 30 percent of the total decay rate (although the total is not significantly changed). The vectors do not contribute much. Our model produces a reasonable estimate for the related a{sub 0}(980) - f{sub 0}(980) mixing strength, which has been a topic of current debate. Promising directions …
Date: October 1, 2002
Creator: Abdel-Rehim, Abdou; Black, Deirdre; Fariborz, Amir H. & Schechter, Joseph
Object Type: Article
System: The UNT Digital Library
High Sensitivity Neutron Assay of Grouted Spent Nuclear Fuel Sludge at Hanford (open access)

High Sensitivity Neutron Assay of Grouted Spent Nuclear Fuel Sludge at Hanford

The disposal of the North Loadout Pit (NLOP) waste at Hanford will produce 208-liter grouted sludge drums bearing transuranic (TRU) radionuclides and fission products. Discrimination between low level waste (LLW) and TRU waste requires a lower limit of detection (LLD) of less than 100 nCi (3700 Bq) of TRU alpha activity per gram of waste matrix in order to correctly certify the final waste form. Hanford's Waste Receiving and Processing (WRAP) facility operates two identical Imaging Passive Active Neutron (IPAN{trademark}) systems which had previously demonstrated this low detection limit capability for debris waste. These two IPAN{trademark} systems were selected as the appropriate technology to assay this challenging waste stream.
Date: October 12, 2007
Creator: Abdurrahman, N. M.
Object Type: Article
System: The UNT Digital Library
Neutronic Benchmarks for the Utilization of Mixed-Oxide Fuel: Joint U.S./Russian Progress Report for Fiscal Year 1997 - Volume 4, Part 2--Saxton Plutonium Program Critical Experiments (open access)

Neutronic Benchmarks for the Utilization of Mixed-Oxide Fuel: Joint U.S./Russian Progress Report for Fiscal Year 1997 - Volume 4, Part 2--Saxton Plutonium Program Critical Experiments

Critical experiments with water-moderated, single-region PuO{sub 2}-UO{sub 2} or UO{sub 2}, and multiple-region PuO{sub 2}-UO{sub 2}- and UO{sub 2}-fueled cores were performed at the CRX reactor critical facility at the Westinghouse Reactor Evaluation Center (WREC) at Waltz Mill, Pennsylvania in 1965 [1]. These critical experiments were part of the Saxton Plutonium Program. The mixed oxide (MOX) fuel used in these critical experiments and then loaded in the Saxton reactor contained 6.6 wt% PuO{sub 2} in a mixture of PuO{sub 2} and natural UO{sub 2}. The Pu metal had the following isotopic mass percentages: 90.50% {sup 239}Pu; 8.57% {sup 239}Pu; 0.89% {sup 240}Pu; and 0.04% {sup 241}Pu. The purpose of these critical experiments was to verify the nuclear design of Saxton partial plutonium cores while obtaining parameters of fundamental significance such as buckling, control rod worth, soluble poison worth, flux, power peaking, relative pin power, and power sharing factors of MOX and UO{sub 2} lattices. For comparison purposes, the core was also loaded with uranium dioxide fuel rods only. This series is covered by experiments beginning with the designation SX.
Date: October 12, 2000
Creator: Abdurrahman, NM
Object Type: Report
System: The UNT Digital Library
Electric Transmission: Approaches for Energizing a Sagging Industry (open access)

Electric Transmission: Approaches for Energizing a Sagging Industry

This report discusses factors that have contributed to the lack of new transmission capacity and some of the resulting issues.
Date: October 3, 2007
Creator: Abel, Amy
Object Type: Report
System: The UNT Digital Library
Government Activities to Protect the Electric Grid (open access)

Government Activities to Protect the Electric Grid

This report provides a description of initiatives within the Federal Energy Regulatory Commission and the Departments of Energy, Homeland Security, and Defense to protect the physical transmission infrastructure.
Date: October 20, 2004
Creator: Abel, Amy
Object Type: Report
System: The UNT Digital Library
Electricity: The Road Toward Restructuring (open access)

Electricity: The Road Toward Restructuring

The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: October 16, 2002
Creator: Abel, Amy & Parker, Larry
Object Type: Report
System: The UNT Digital Library
Noncontact surface thermometry for microsystems: LDRD final report. (open access)

Noncontact surface thermometry for microsystems: LDRD final report.

We describe a Laboratory Directed Research and Development (LDRD) effort to develop and apply laser-based thermometry diagnostics for obtaining spatially resolved temperature maps on working microelectromechanical systems (MEMS). The goal of the effort was to cultivate diagnostic approaches that could adequately resolve the extremely fine MEMS device features, required no modifications to MEMS device design, and which did not perturb the delicate operation of these extremely small devices. Two optical diagnostics were used in this study: microscale Raman spectroscopy and microscale thermoreflectance. Both methods use a low-energy, nonperturbing probe laser beam, whose arbitrary wavelength can be selected for a diffraction-limited focus that meets the need for micron-scale spatial resolution. Raman is exploited most frequently, as this technique provides a simple and unambiguous measure of the absolute device temperature for most any MEMS semiconductor or insulator material under steady state operation. Temperatures are obtained from the spectral position and width of readily isolated peaks in the measured Raman spectra with a maximum uncertainty near {+-}10 K and a spatial resolution of about 1 micron. Application of the Raman technique is demonstrated for V-shaped and flexure-style polycrystalline silicon electrothermal actuators, and for a GaN high-electron-mobility transistor. The potential of the Raman technique …
Date: October 1, 2006
Creator: Abel, Mark (Georgia Institute of Technology, Atlanta, GA); Beecham, Thomas (Georgia Institute of Technology, Atlanta, GA); Graham, Samuel (Georgia Institute of Technology, Atlanta, GA); Kearney, Sean Patrick; Serrano, Justin Raymond & Phinney, Leslie Mary
Object Type: Report
System: The UNT Digital Library
Measurement of Transverse Single-Spin Asymmetries for Di-JetProduction in Proton-Proton Collisions at sqrt s = 200 GeV (open access)

Measurement of Transverse Single-Spin Asymmetries for Di-JetProduction in Proton-Proton Collisions at sqrt s = 200 GeV

We report the first measurement of the opening angledistribution between pairs of jets produced in high-energy collisions oftransversely polarized protons. The measurement probes (Sivers)correlations between the transverse spin orientation of a proton and thetransverse momentum directions of its partons. With both beams polarized,the wide pseudorapidity (-1 leq eta leq +2) coverage for jets permitsseparation of Sivers functions for the valence and sea regions. Theresulting asymmetries are all consistent with zero and considerablysmaller than Sivers effects observed in semi-inclusive deep inelasticscattering (SIDIS). We discuss theoretical attempts to reconcile the newresults with the sizable transverse spin effects seen in SIDIS andforward hadron production in pp collisions.
Date: October 2, 2007
Creator: Abelev, B. I.; Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Object Type: Article
System: The UNT Digital Library
Adaptive Control Optimization of Cutting Parameters for High Quality Machining Operations based on Neural Networks and Search Algorithms (open access)

Adaptive Control Optimization of Cutting Parameters for High Quality Machining Operations based on Neural Networks and Search Algorithms

This book chapter presents an Adaptive Control with Optimization (ACO) system for optimising a multi-objective function based on material removal rate, quality loss function related to surface roughness, and cutting-tool life subjected to surface roughness specifications constraint.
Date: October 1, 2008
Creator: Abellan, J. V.; Romero, F.; Siller Carrillo, Héctor Rafael; Estruch, A. & Vila, C.
Object Type: Book Chapter
System: The UNT Digital Library
Prototype Weigh-In-Motion Performance (open access)

Prototype Weigh-In-Motion Performance

Oak Ridge National Laboratory (ORNL) has developed and patented methods to weigh slowly moving vehicles. We have used this technology to produce a portable weigh-in-motion system that is robust and accurate. This report documents the performance of the second-generation portable weigh-in-motion prototype (WIM Gen II). The results of three modes of weight determination are compared in this report: WIM Gen II dynamic mode, WIM Gen II stop-and-go mode, and static (parked) mode on in-ground, static scales. The WIM dynamic mode measures axle weights as the vehicle passes over the system at speeds of 3 to 7 miles per hour (1.3 to 3.1 meters/second). The WIM stop-and-go mode measures the weight of each axle of the vehicle as the axles are successively positioned on a side-by-side pair of WIM measurement pads. In both measurement modes the center of balance (CB) and the total weight are obtained by a straight-forward calculation from axle weights and axle spacings. The performance metric is measurement error (in percent), which is defined as 100 x (sample standard deviation)/(average); see Appendix A for details. We have insufficient data to show that this metric is predictive. This report details the results of weight measurements performed in May 2005 …
Date: October 1, 2006
Creator: Abercrombie, Robert K; Beshears, David L; Hively, Lee M; Scudiere, Matthew B & Sheldon, Frederick T
Object Type: Report
System: The UNT Digital Library
Thermodynamic ground states of platinum metal nitrides (open access)

Thermodynamic ground states of platinum metal nitrides

We have systematically studied the thermodynamic stabilities of various phases of the nitrides of the platinum metal elements using density functional theory. We show that for the nitrides of Rh, Pd, Ir and Pt two new crystal structures, in which the metal ions occupy simple tetragonal lattice sites, have lower formation enthalpies at ambient conditions than any previously proposed structures. The region of stability can extend up to 17 GPa for PtN{sub 2}. Furthermore, we show that according to calculations using the local density approximation, these new compounds are also thermodynamically stable at ambient pressure and thus may be the ground state phases for these materials. We further discuss the fact that the local density and generalized gradient approximations predict different values of the absolute formation enthalpies as well different relative stabilities between simple tetragonal and the pyrite or marcasite structures.
Date: October 9, 2007
Creator: Aberg, D; Sadigh, B; Crowhurst, J & Goncharov, A
Object Type: Article
System: The UNT Digital Library
Propuesta metodológica para el control de calidad de datos de precipitación (open access)

Propuesta metodológica para el control de calidad de datos de precipitación

Article discussing a methodological proposal for the quality control of precipitation data.
Date: October 23, 2007
Creator: Ablan, Magdiel; Andressen, Rigoberto; Vargas, Mary Pili & Acevedo, Miguel F.
Object Type: Article
System: The UNT Digital Library
NEW PARADIGM IN SEPARATIONS: MOLECULAR RECOGNITION MEMBRANES (open access)

NEW PARADIGM IN SEPARATIONS: MOLECULAR RECOGNITION MEMBRANES

None
Date: October 1, 2000
Creator: Abney, K.D. & Barr, M.E.
Object Type: Article
System: The UNT Digital Library
Report of the APS Neutrino Study Reactor Working Group (open access)

Report of the APS Neutrino Study Reactor Working Group

The worldwide program to understand neutrino oscillations and determine the neutrino mixing parameters, CP violating effects, and mass hierarchy will require a broad combination of measurements. The group believes that a key element of this future neutrino program is a multi-detector neutrino experiment (with baselines of {approx} 200 m and {approx} 1.5 km) with a sensitivity of sin{sup 2} 2{theta}{sub 13} = 0.01. In addition to oscillation physics, the reactor experiment may provide interesting measurements of sin{sup 2} {theta}{sub W} at Q{sup 2} = 0, neutrino couplings, magnetic moments, and mixing with sterile neutrino states. {theta}{sub 13} is one of the twenty-six parameters of the standard model, the best model of electroweak interactions for energies below 100 GeV and, as such, is worthy of a precision measurement independent of other considerations. A reactor experiment of the proposed sensitivity will allow a measurement of {theta}{sub 13} with no ambiguities and significantly better precision than any other proposed experiment, or will set limits indicating the scale of future experiments required to make progress. Figure 1 shows a comparison of the sensitivity of reactor experiments of different scales with accelerator experiments for setting limits on sin{sup 2} 2{theta}{sub 13} if the mixing angle …
Date: October 28, 2004
Creator: Abouzaid, E.; Anderson, K.; Barenboim, G.; Berger, B.; Blucher, E.; Bolton, T. et al.
Object Type: Report
System: The UNT Digital Library
Correlation and prediction of partition coefficients between the gas phase and water, and the solvents dodecane and undecane (open access)

Correlation and prediction of partition coefficients between the gas phase and water, and the solvents dodecane and undecane

Article on the correlation and prediction of partition coefficients between the gas phase and water, and the solvents dodecane and undecane.
Date: October 29, 2004
Creator: Abraham, M. H. (Michael H.) & Acree, William E. (William Eugene)
Object Type: Article
System: The UNT Digital Library
COLD TEST LOOP INTEGRATED TEST LOOP RESULTS (open access)

COLD TEST LOOP INTEGRATED TEST LOOP RESULTS

A testing facility (Cold Test Loop) was constructed and operated to demonstrate the efficacy of the Accelerated Waste Retrieval (AWR) Project's planned sluicing approach to the remediation of Silos 1 and 2 at the Fernald Environmental Management Project near Cincinnati, Ohio. The two silos contain almost 10,000 tons of radium-bearing low-level waste, which consists primarily of solids of raffinates from processing performed on ores from the Democratic Republic of Congo (commonly referred to as ''Belgium Congo ores'') for the recovery of uranium. These silos are 80 ft in diameter, 36 ft high to the center of the dome, and 26.75 ft to the top of the vertical side walls. The test facility contained two test systems, each designed for a specific purpose. The first system, the Integrated Test Loop (ITL), a near-full-scale plant including the actual equipment to be installed at the Fernald Site, was designed to demonstrate the sluicing operation and confirm the selection of a slurry pump, the optimal sluicing nozzle operation, and the preliminary design material balance. The second system, the Component Test Loop (CTL), was designed to evaluate many of the key individual components of the waste retrieval system over an extended run. The major results …
Date: October 22, 2003
Creator: Abraham, TJ
Object Type: Report
System: The UNT Digital Library
EARLY ENTRANCE COPRODUCTION PLANT (open access)

EARLY ENTRANCE COPRODUCTION PLANT

The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstock. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing Plan (RD and T) for implementation in Phase II. The objective of Phase II is to implement the RD and T as outlined in the Phase I RD and T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and other feedstocks. The objective of Phase III is to develop an engineering design package and a financing plan for …
Date: October 26, 2000
Creator: Abughazaleh, John S.; Ahmed, Mushtaq; Anand, Ashok; Anderson, John H.; Benham, Charles; Brent, Fred D. et al.
Object Type: Report
System: The UNT Digital Library
Measurement of the Ratios of Branching Fractions B(Bs -> Ds pi pi pi) / B(Bd -> Dd pi pi pi) and B(Bs -> Ds pi) / B(Bd -> Dd pi) (open access)

Measurement of the Ratios of Branching Fractions B(Bs -> Ds pi pi pi) / B(Bd -> Dd pi pi pi) and B(Bs -> Ds pi) / B(Bd -> Dd pi)

Using 355 pb{sup -1} of data collected by the CDF II detector in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron, they study the fully reconstructed hadronic decays B{sub (s)}{sup 0} {yields} D{sub (s)}{sup -}{pi}{sup +} and B{sub (s)}{sup 0} {yields} D{sub (s)}{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}. They present the first measurement of the ratio of branching fractions {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(B{sup 0} {yields} D{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}) = 1.05 {+-} 0.10(stat.) {+-} 0.22(syst.). They also update their measurement of {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +})/{Beta}(B{sup 0} {yields} D{sup -} {pi}{sup +}) to 1.13 {+-} 0.08(stat.) {+-} 0.23(syst.) improving the statistical uncertainty by more than a factor of two. They find {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}) = [3.8 {+-} 0.3(stat.) {+-} 1.3(syst.)] x 10{sup -3} and {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}) = [8.4 {+-} 0.8(stat.) {+-} 3.2(syst.)] x 10{sup -3}.
Date: October 1, 2006
Creator: Abulencia, A.; /Illinois U., Urbana; Adelman, J.; U., /Chicago; Affolder, T.; /UC, Santa Barbara et al.
Object Type: Article
System: The UNT Digital Library
A Detailed Chemical Kinetic Analysis of Low Temperature Non-Sooting Diesel Combustion (open access)

A Detailed Chemical Kinetic Analysis of Low Temperature Non-Sooting Diesel Combustion

We have developed a model of the diesel fuel injection process for application to analysis of low temperature non-sooting combustion. The model uses a simplified mixing correlation and detailed chemical kinetics, and analyzes a parcel of fuel as it moves along the fuel jet, from injection into evaporation and ignition. The model predicts chemical composition and soot precursors, and is applied at conditions that result in low temperature non-sooting combustion. Production of soot precursors is the first step toward production of soot, and modeling precursor production is expected to give insight into the overall evolution of soot inside the engine. The results of the analysis show that the model has been successful in describing many of the observed characteristics of low temperature combustion. The model predicts results that are qualitatively similar to those obtained for soot formation experiments at conditions in which the EGR rate is increased from zero to very high values as the fueling rate is kept constant. The model also describes the two paths to achieve non-sooting combustion. The first is smokeless rich combustion and the second is modulated kinetics (MK). The importance of the temperature after ignition and the equivalence ratio at the time of ignition …
Date: October 1, 2004
Creator: Aceves, S M & Flowers, D L
Object Type: Article
System: The UNT Digital Library
Kahler Independence of the G2-MSSM (open access)

Kahler Independence of the G2-MSSM

The G{sub 2}-MSSM is a model of particle physics coupled to moduli fields with interesting phenomenology both for colliders and astrophysical experiments. In this paper we consider a more general model--whose moduli Kahler potential is a completely arbitrary G{sub 2}-holonomy Kahler potential and whose matter Kahler potential is also more general. We prove that the vacuum structure and spectrum of BSM particles is largely unchanged in this much more general class of theories. In particular, gaugino masses are still suppressed relative to the gravitino mass and moduli masses. We also consider the effects of higher order corrections to the matter Kahler potential and find a connection between the nature of the LSP and flavor effects.
Date: October 31, 2008
Creator: Acharya, Bobby S. & Bobkov, Konstantin
Object Type: Article
System: The UNT Digital Library
University Press (Beaumont, Tex.), Vol. 79, No. 8, Ed. 1 Wednesday, October 9, 2002 (open access)

University Press (Beaumont, Tex.), Vol. 79, No. 8, Ed. 1 Wednesday, October 9, 2002

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: October 9, 2002
Creator: Achilles, Jenny
Object Type: Newspaper
System: The Portal to Texas History
University Press (Beaumont, Tex.), Vol. 79, No. 9, Ed. 1 Friday, October 11, 2002 (open access)

University Press (Beaumont, Tex.), Vol. 79, No. 9, Ed. 1 Friday, October 11, 2002

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: October 11, 2002
Creator: Achilles, Jenny
Object Type: Newspaper
System: The Portal to Texas History
University Press (Beaumont, Tex.), Vol. 79, No. 9, Ed. 1 Wednesday, October 16, 2002 (open access)

University Press (Beaumont, Tex.), Vol. 79, No. 9, Ed. 1 Wednesday, October 16, 2002

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: October 16, 2002
Creator: Achilles, Jenny
Object Type: Newspaper
System: The Portal to Texas History