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222-S LABORATORY FUME HOOD TESTING STUDY (open access)

222-S LABORATORY FUME HOOD TESTING STUDY

The 222-S Laboratory contains 155 active fume hoods that are used to support analytical work with radioactive and/or toxic materials. The performance of a fume hood was brought into question after employees detected odors in the work area while mixing chemicals within the subject fume hood. Following the event, testing of the fume hood was conducted to assess the performance of the fume hood. Based on observations from the testing, it was deemed appropriate to conduct performance evaluations of other fume hoods within the laboratory.
Date: March 26, 2007
Creator: Ruelas, B. H.
Object Type: Report
System: The UNT Digital Library
6th Workshop on Fast Ignition of Fusion Targets (open access)

6th Workshop on Fast Ignition of Fusion Targets

None
Date: March 26, 2003
Creator: Key, M H
Object Type: Report
System: The UNT Digital Library
Ab Initio Many-Body Calculations Of n-3H, n-4He, p-3,4He, And n-10Be Scattering (open access)

Ab Initio Many-Body Calculations Of n-3H, n-4He, p-3,4He, And n-10Be Scattering

We develop a new ab initio many-body approach capable of describing simultaneously both bound and scattering states in light nuclei, by combining the resonating-group method with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters. This approach preserves translational symmetry and Pauli principle. We present phase shifts for neutron scattering on {sup 3}H, {sup 4}He and {sup 10}Be and proton scattering on {sup 3,4}He, using realistic nucleon-nucleon potentials. Our A = 4 scattering results are compared to earlier ab initio calculations. We demonstrate that a proper treatment of the coupling to the n-{sup 10}Be continuum is essential to explain the parity-inverted ground state in {sup 11}Be.
Date: March 26, 2008
Creator: Quaglioni, S & Navratil, P
Object Type: Article
System: The UNT Digital Library
Achieving Finite Element Mesh Quality via Optimization of the Jacobian Matrix Norm and Associated Quantities, Part II - A Framework for Volume Mesh Optimization and the Condition Number of the Jacobian Matrix (open access)

Achieving Finite Element Mesh Quality via Optimization of the Jacobian Matrix Norm and Associated Quantities, Part II - A Framework for Volume Mesh Optimization and the Condition Number of the Jacobian Matrix

Three-dimensional unstructured tetrahedral and hexahedral finite element mesh optimization is studied from a theoretical perspective and by computer experiments to determine what objective functions are most effective in attaining valid, high quality meshes. The approach uses matrices and matrix norms to extend the work in Part I to build suitable 3D objective functions. Because certain matrix norm identities which hold for 2 x 2 matrices do not hold for 3 x 3 matrices. significant differences arise between surface and volume mesh optimization objective functions. It is shown, for example, that the equivalence in two-dimensions of the Smoothness and Condition Number of the Jacobian matrix objective functions does not extend to three dimensions and further. that the equivalence of the Oddy and Condition Number of the Metric Tensor objective functions in two-dimensions also fails to extend to three-dimensions. Matrix norm identities are used to systematically construct dimensionally homogeneous groups of objective functions. The concept of an ideal minimizing matrix is introduced for both hexahedral and tetrahedral elements. Non-dimensional objective functions having barriers are emphasized as the most logical choice for mesh optimization. The performance of a number of objective functions in improving mesh quality was assessed on a suite of realistic …
Date: March 26, 1999
Creator: Knupp, P.M.
Object Type: Article
System: The UNT Digital Library
Active control for turbulent premixed flame simulations (open access)

Active control for turbulent premixed flame simulations

Many turbulent premixed flames of practical interest are statistically stationary. They occur in combustors that have anchoring mechanisms to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity that is prohibitive for detailed computational studies of turbulent flame dynamics. As a result, typical detailed simulations are performed in simplified model configurations such as decaying isotropic turbulence or inflowing turbulence. In these configurations, the turbulence seen by the flame either decays or, in the latter case, increases as the flame accelerates toward the turbulent inflow. This limits the duration of the eddy evolutions experienced by the flame at a given level of turbulent intensity, so that statistically valid observations cannot be made. In this paper, we apply a feedback control to computationally stabilize an otherwise unstable turbulent premixed flame in two dimensions. For the simulations, we specify turbulent in flow conditions and dynamically adjust the integrated fueling rate to control the mean location of the flame in the domain. We outline the numerical procedure, and illustrate the behavior of the control algorithm. We use the simulations to study the propagation and the local chemical variability of turbulent flame chemistry.
Date: March 26, 2004
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F. & Lijewski, Michael J.
Object Type: Article
System: The UNT Digital Library
Adapting the decomposable mandrel technique to build specialty ICF targets (open access)

Adapting the decomposable mandrel technique to build specialty ICF targets

None
Date: March 26, 1997
Creator: Fearon, E. M.; Letts, S. A.; Allison, L. M. & Cook, R. C.
Object Type: Article
System: The UNT Digital Library
Adaptive Sampling for Noisy Problems (open access)

Adaptive Sampling for Noisy Problems

The usual approach to deal with noise present in many real-world optimization problems is to take an arbitrary number of samples of the objective function and use the sample average as an estimate of the true objective value. The number of samples is typically chosen arbitrarily and remains constant for the entire optimization process. This paper studies an adaptive sampling technique that varies the number of samples based on the uncertainty of deciding between two individuals. Experiments demonstrate the effect of adaptive sampling on the final solution quality reached by a genetic algorithm and the computational cost required to find the solution. The results suggest that the adaptive technique can effectively eliminate the need to set the sample size a priori, but in many cases it requires high computational costs.
Date: March 26, 2004
Creator: Cantu-Paz, E
Object Type: Article
System: The UNT Digital Library
Advanced Dark Energy Physics Telescope (ADEPT) (open access)

Advanced Dark Energy Physics Telescope (ADEPT)

In 2006, we proposed to NASA a detailed concept study of ADEPT (the Advanced Dark Energy Physics Telescope), a potential space mission to reliably measure the time-evolution of dark energy by conducting the largest effective volume survey of the universe ever done. A peer-review panel of scientific, management, and technical experts reported back the highest possible 'excellent' rating for ADEPT. We have since made substantial advances in the scientific and technical maturity of the mission design. With this Department of Energy (DOE) award we were granted supplemental funding to support specific extended research items that were not included in the NASA proposal, many of which were intended to broadly advance future dark energy research, as laid out by the Dark Energy Task Force (DETF). The proposed work had three targets: (1) the adaptation of large-format infrared arrays to a 2 micron cut-off; (2) analytical research to improve the understanding of the dark energy figure-of- merit; and (3) extended studies of baryon acoustic oscillation systematic uncertainties. Since the actual award was only for {approx}10% of the proposed amount item (1) was dropped and item (2) work was severely restricted, consistent with the referee reviews of the proposal, although there was considerable …
Date: March 26, 2009
Creator: Bennett, Charles L.
Object Type: Report
System: The UNT Digital Library
AGS Silicon Gold Collisions Measured in the E-810 TPC (Time Projection Chamber) (open access)

AGS Silicon Gold Collisions Measured in the E-810 TPC (Time Projection Chamber)

The tracking detector of AGS Experiment 810 is a three-piece Time Projection Chamber (TPC) intended to measure all charged tracks in the forward hemisphere of the nucleon-nucleon center of mass system, i.e. forward of an angle of about 20 degrees in the lab. Each module of the TPC contains twelve rows of short anode wires which give 3-D space points on each track, but no dE/dx information useable for particle identification. The TPC was operated in a beam of silicon ions at the end of June 1989 and this talk reports the results of analysis of the data taken with a thin gold target in that run. We have gathered a similar amount of data from thin copper and silicon targets, the analysis of which is in a less advanced state. The results of our investigation of the neutral strange particle decays appear in a separate contribution by Al Saulys. This paper presents the current state of the analysis of the charged tracks from the silicon gold collisions. 1 ref., 15 figs.
Date: March 26, 1990
Creator: Bonner, B. E.; Buchanan, J. A.; Chiou, C. N.; Clement, J. M.; Corcoran, M. D.; Kruk, J. W. et al.
Object Type: Article
System: The UNT Digital Library
Alloying Characteristics of the Rare Earth Elements with the Transition Elements (open access)

Alloying Characteristics of the Rare Earth Elements with the Transition Elements

This report talks about the Alloying Characteristics of the Rare Earth Elements with the Transition Elements
Date: March 26, 1963
Creator: Sheeley, W. F.
Object Type: Report
System: The UNT Digital Library
Alpha irradiation modeling (open access)

Alpha irradiation modeling

With the end of the Cold War and the associated limitations imposed on the nuclear weapons stockpile by strategic arms treaties, much has changed in the stockpile stewardship program. Weapons that were originally designed for stockpile lives on the order of 15 to 20 years are now being evaluated for much longer periods: in some cases as much as 60 years. As such, issues that were once considered to be of no consequence are being reexamined. Among these is the extent of the radiation dose received by secondary organics over time that results from the intrinsic alpha source of the weapon components. This report describes the results of work performed to estimate the alpha radiation deposition in the organic components of an LLNL system at specific points in its stockpile life. Included are discussions of the development of the intrinsic time- and energy-dependent alpha source term per unit mass, estimation of the effective source and absorber material thicknesses, development of a simplified model for the total intrinsic alpha source term and energy deposition in the absorber, and the alpha radiation deposition in the organic components of a selected LLNL weapon.
Date: March 26, 1999
Creator: Keeton, S C & Mount, M E
Object Type: Article
System: The UNT Digital Library
Analyzing water/wastewater infrastructure interdependencies. (open access)

Analyzing water/wastewater infrastructure interdependencies.

This paper describes four general categories of infrastructure interdependencies (physical, cyber, geographic, and logical) as they apply to the water/wastewater infrastructure, and provides an overview of one of the analytic approaches and tools used by Argonne National Laboratory to evaluate interdependencies. Also discussed are the dimensions of infrastructure interdependency that create spatial, temporal, and system representation complexities that make analyzing the water/wastewater infrastructure particularly challenging. An analytical model developed to incorporate the impacts of interdependencies on infrastructure repair times is briefly addressed.
Date: March 26, 2002
Creator: Gillette, J. L.; Fisher, R. E.; Peerenboom, J. P. & Whitfield, R. G.
Object Type: Article
System: The UNT Digital Library
D and Ds Spectroscopy (open access)

D and Ds Spectroscopy

None
Date: March 26, 2013
Creator: Schroder, T. & /Ruhr U., Bochum
Object Type: Article
System: The UNT Digital Library
LOS ANGELES DEPARTMENT OF WATER AND POWER FUEL CELL DEMONSTRATION PROJECT (open access)

LOS ANGELES DEPARTMENT OF WATER AND POWER FUEL CELL DEMONSTRATION PROJECT

The Los Angeles Department of Water and Power (LADWP) is currently one of the most active electric utility companies in deploying fuel cell technology. Fuel cells offer many benefits and are now used as an alternative to traditional internal combustion engines in power generation. In continuing it's role as the leader in fuel cell deploying, LADWP installed a Phosphoric Acid Fuel Cell (PAFC) in February 2002 at its Main Street service center. The goal of this project is to evaluate the PAFC's performance and cost benefits. This will provide LADWP an insight for future deployment of fuel cell technology. The fuel cell ran smoothly through the first year of operation with very high efficiency and availability, and only with some minor setbacks. The Main street fuel cell project is funded by LADWP with partial grant funding from the Department of Defense's Climate Change Fuel Cell Buydown Program. The technical evaluation and the benefit-cost evaluation of the Main Street fuel cell are both examined in this report.
Date: March 26, 2004
Creator: Glauz, William W.
Object Type: Report
System: The UNT Digital Library
Annual Site Environmental Report for Calendar Year 2004 (open access)

Annual Site Environmental Report for Calendar Year 2004

This report provides the U.S. Department of Energy (DOE) and the public with information on the level of radioactive and non-radioactive pollutants (if any) that are added to the environment as a result of Princeton Plasma Physics Laboratory's (PPPL) operations. The results of the 2004 environmental surveillance and monitoring program for PPPL's are presented and discussed. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 2004.
Date: March 26, 2009
Creator: Finley, V.
Object Type: Report
System: The UNT Digital Library
ANSWERS TO QUESTIONS ON OFF-GAS TREATMENT. Eurochemic Assistance Program: Comments by HAPO, dated March 12, 1959, on Questions by E.L. Nicholson (open access)

ANSWERS TO QUESTIONS ON OFF-GAS TREATMENT. Eurochemic Assistance Program: Comments by HAPO, dated March 12, 1959, on Questions by E.L. Nicholson

Information relative to the performance and operation of silver reactors is presented. The information is given as answers to questions submitted in the USAECEurochemic Company cooperative program. The answers to 8 questions are presented along with the basis for comments. (J.R.D.)
Date: March 26, 1959
Creator: Bupp, L. P.
Object Type: Report
System: The UNT Digital Library
The Application of Range Space Operations to Color Images (open access)

The Application of Range Space Operations to Color Images

The knowledge gained from scientific observation, experiment, and simulation is linked to the ability to analyze, understand, and manage the generated results. These abilities are increasingly at odds with the current, and future, capabilities to generate enormous quantities of raw scientific and engineering data from instruments, sensors, and computers. Many researchers are currently engaged in activities that seek to create new and novel methods for analyzing, understanding, and managing these vast collections of data. In this work, we present some of our research in addressing a particular type of problem in this broad undertaking. Much the scientific data of interest is in the form of observed, measured, or computed multivariate or multi-component vector field data--with either as physical or color data values. We are currently researching methods and techniques for working with this type of vector data through the use of a novel analysis technique. Our basic approach is to work with the vector field data in its natural physical or color space. When the data is viewed as a functional mapping of a domain, usually an index space, to a range, the physical or color values, potentially interesting characteristics of the data present themselves. These characteristics are useful in …
Date: March 26, 2002
Creator: Baldwin, Chuck & Duchaineau, Mark
Object Type: Article
System: The UNT Digital Library
Assembly conductance measurements: halthane vent path testing (open access)

Assembly conductance measurements: halthane vent path testing

The purpose of this test was to characterize the conductance of different configurations of vent paths put into weapons assemblies through application of Halthane 88-3 precoats onto the parts. Conductance is a measure of the ease of gas flow in an assembly. It is the inverse of resistance which may be more familiar to most readers. It is defined as the resultant of the gas flow (torr-1/sec) divided by the pressure drop (torr) in the assembly. Its dimensions are thus liters per second. The conductance paths are put into the precoats to allow pumpdown of weapon assemblies and communication during stockpile life. They are put into the precoats by applying tape of the desired width onto the part prior to coating. The Halthane 88-3 is then rolled onto the part and when the tape is removed the vent paths are left. To keep this report unclassified some of the description of the situation has been abbreviated. For a more complete description of the device configuration and conductance issue, see the final report on WDW 9009-A and -B (CODT 98-0809).
Date: March 26, 1999
Creator: Beat, T G & Kervin, J E
Object Type: Article
System: The UNT Digital Library
Assessment of Alternative RF Linac Structures for APT (open access)

Assessment of Alternative RF Linac Structures for APT

The APT program has been examining both normal and superconducting variants of the APT linac for the past two years. A decision on which of the two will be the selected technology will depend upon several considerations including the results of ongoing feasibility experiments, the performance and overall attractiveness of each of the design concepts, and an assessment of the system-level features of both alternatives. The primary objective of the Assessment of Alternative RF Linac Structures for APT study reported herein was to assess and compare, at the system-level, the performance, capital and life cycle costs, reliability/availability/maintainability (RAM) and manufacturing schedules of APT RF linear accelerators based upon both superconducting and normal conducting technologies. A secondary objective was to perform trade studies to explore opportunities for system optimization, technology substitution and alternative growth pathways and to identify sensitivities to design uncertainties.
Date: March 26, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Attrition Resistant Iron-Based Fischer-Tropsch Catalysts (open access)

Attrition Resistant Iron-Based Fischer-Tropsch Catalysts

The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRS) can largely solve this problem. Iron-based (Fe) catalysts are preferred catalysts for F-T when using low CO/H{sub 2} ratio synthesis gases derived from modem coal gasifiers. This is because in addition to reasonable F-T activity, the FT catalysts also possess high water gas shift (WGS) activity. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, making the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. The objectives of this research are to develop a better understanding of the parameters affecting attrition resistance of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. Catalyst preparations will be based on the use of spray …
Date: March 26, 1997
Creator: Jothimurugesan, K.; Goodwin, J. G.; Spivey, J. J. & Gangwal, S. K.
Object Type: Report
System: The UNT Digital Library
Automatic Blocking Of QR and LU Factorizations for Locality (open access)

Automatic Blocking Of QR and LU Factorizations for Locality

QR and LU factorizations for dense matrices are important linear algebra computations that are widely used in scientific applications. To efficiently perform these computations on modern computers, the factorization algorithms need to be blocked when operating on large matrices to effectively exploit the deep cache hierarchy prevalent in today's computer memory systems. Because both QR (based on Householder transformations) and LU factorization algorithms contain complex loop structures, few compilers can fully automate the blocking of these algorithms. Though linear algebra libraries such as LAPACK provides manually blocked implementations of these algorithms, by automatically generating blocked versions of the computations, more benefit can be gained such as automatic adaptation of different blocking strategies. This paper demonstrates how to apply an aggressive loop transformation technique, dependence hoisting, to produce efficient blockings for both QR and LU with partial pivoting. We present different blocking strategies that can be generated by our optimizer and compare the performance of auto-blocked versions with manually tuned versions in LAPACK, both using reference BLAS, ATLAS BLAS and native BLAS specially tuned for the underlying machine architectures.
Date: March 26, 2004
Creator: Yi, Q; Kennedy, K; You, H; Seymour, K & Dongarra, J
Object Type: Article
System: The UNT Digital Library
Bases, Assumptions, and Results of the Flowsheet Calculations for the Decision Phase Salt Disposition Alternatives (open access)

Bases, Assumptions, and Results of the Flowsheet Calculations for the Decision Phase Salt Disposition Alternatives

The High Level Waste (HLW) Salt Disposition Systems Engineering Team was formed on March 13, 1998, and chartered to identify options, evaluate alternatives, and recommend a selected alternative(s) for processing HLW salt to a permitted wasteform. This requirement arises because the existing In-Tank Precipitation process at the Savannah River Site, as currently configured, cannot simultaneously meet the HLW production and Authorization Basis safety requirements. This engineering study was performed in four phases. This document provides the technical bases, assumptions, and results of this engineering study.
Date: March 26, 2001
Creator: Dimenna, R. A.; Jacobs, R. A.; Taylor, G. A.; Durate, O. E.; Paul, P. K.; Elder, H. H. et al.
Object Type: Report
System: The UNT Digital Library
Beam Loss Studies for Rare Isotope Driver Linacs Final Report (open access)

Beam Loss Studies for Rare Isotope Driver Linacs Final Report

The Fortran 90 RIAPMTQ/IMPACT code package is a pair of linked beam-dynamics simulation codes that have been developed for end-to-end computer simulations of multiple-charge-state heavy-ion linacs for future exotic-beam facilities. These codes have multiple charge-state capability, and include space-charge forces. The simulations can extend from the low-energy beam-transport line after an ECR ion source to the end of the linac. The work has been performed by a collaboration including LANL, LBNL, ANL, and MSU. The code RIAPMTQ simulates the linac front-end beam dynamics including the LEBT, RFQ, and MEBT. The code IMPACT simulates the beam dynamics of the main superconducting linac. The codes have been benchmarked for rms beam properties against previously existing codes at ANL and MSU. The codes allow high-statistics runs on parallel supercomputing platforms, particularly at NERSC at LBNL, for studies of beam losses. The codes also run on desktop PC computers for low-statistics work. The code package is described in more detail in a recent publication [1] in the Proceedings of PAC07 (2007 US Particle Accelerator Conference). In this report we describe the main activities for the FY07 beam-loss studies project using this code package.
Date: March 26, 2008
Creator: Wangler, T. P.; Kurennoy, S. S.; Billen, J. H.; Crandall, K. R.; Qiang, J.; Ryne, R. D. et al.
Object Type: Report
System: The UNT Digital Library
Beam model for non-planar orbits in synchrotrons (open access)

Beam model for non-planar orbits in synchrotrons

A framework has been developed for a beam model in the case of synchrotron orbits not confined to a plane. An appropriate moving reference system for the analysis of beam stability has been introduced. As examples of strong perturbations to median plane symmetry, two geometries for the overpass for the Tevatron collider are considered.
Date: March 26, 1984
Creator: Month, M.
Object Type: Report
System: The UNT Digital Library