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Repository post-sealing risk analysis using MACRO. [MACRO]

Description: MACRO, a code to propagate probability distributions through a set of linked models, is currently under development at Lawrence Livermore Laboratory. An early version of this code, MACRO1, has been used to assess post-sealing dose to man for simple repository and site models based on actual site data.
Date: February 14, 1980
Creator: Kaufman, A. M.; Edwards, L. L. & O'Connell, W. J.
Partner: UNT Libraries Government Documents Department
open access

Characterization of nuclear waste

Description: Nuclear wastes which are logical candidates for deep geologic disposal include commercial (spent fuel, reprocessing) and defense wastes. It is expected that the 5250 metric tons of spent fuel discharged through the end of 1978 would increase to about 100,000 tons by the end of 2000. The individual characteristics of each waste type (spent fuel, solidified waste, defense wastes) are described in turn. (DLC)
Date: February 14, 1979
Creator: Platt, A. M.
Partner: UNT Libraries Government Documents Department
open access

DESIGN OF THE DEMOSNTRATION BULK VITRIFICATION SYSTEM FOR THE SUPPLEMENTAL TREATMENT OF LOW ACTIVITY TANK WASTE AT HANFORD

Description: In June 2004, the Demonstration Bulk Vitrification System (DBVS) was initiated with the intent to design, construct, and operate a full-scale bulk vitrification pilot-plant to treat low-activity tank waste from Hanford Tank 241-S-109. The DBVS facility uses In-Container Vitrification{trademark} (ICV{trademark}) at the core of the treatment process. The basic process steps combine liquid low-activity waste (LAW) and glassformers; dry the mixture; and then vitrify the mixture in a batch feed-whil… more
Date: February 14, 2008
Creator: JE, VAN BEEK
Partner: UNT Libraries Government Documents Department
open access

Decomposition of the Multistatic Response Matrix and Target Characterization

Description: Decomposition of the time-reversal operator for an array, or equivalently the singular value decomposition of the multistatic response matrix, has been used to improve imaging and localization of targets in complicated media. Typically, each singular value is associated with one scatterer even though it has been shown in several cases that a single scatterer can generate several singular values. In this paper we review the analysis of the time-reversal operator (TRO), or equivalently the multis… more
Date: February 14, 2008
Creator: Chambers, D H
Partner: UNT Libraries Government Documents Department
open access

Versatile microbial surface-display for environmental remediation and biofuels production

Description: Surface display is a powerful technique that utilizes natural microbial functional components to express proteins or peptides on the cell exterior. Since the reporting of the first surface-display system in the mid-1980s, a variety of new systems have been reported for yeast, Gram-positive and Gram-negative bacteria. Non-conventional display methods are emerging, eliminating the generation of genetically modified microorganisms. Cells with surface display are used as biocatalysts, biosorbents a… more
Date: February 14, 2008
Creator: Wu, Cindy H.; Mulchandani, Ashok & Chen, wilfred
Partner: UNT Libraries Government Documents Department
open access

Molecular Dynamics Simulations of Temperature Equilibration in Dense Hydrogen

Description: The temperature equilibration rate in dense hydrogen (for both T{sub i} > T{sub e} and T{sub i} < T{sub e}) has been calculated with large-scale molecular dynamics simulations for temperatures between 10 and 300 eV and densities between 10{sup 20}/cc to 10{sup 24}/cc. Careful attention has been devoted to convergence of the simulations, including the role of semiclassical potentials. We find that for Coulomb logarithms L {approx}> 1, Brown-Preston-Singleton [Brown et al., Phys. Rep. 41… more
Date: February 14, 2008
Creator: Glosli, J; Graziani, F; More, R; Murillo, M; Streitz, F; Surh, M et al.
Partner: UNT Libraries Government Documents Department
open access

An Implementation and Evaluation of the AMLS Method for SparseEigenvalue Problems

Description: We describe an efficient implementation and present aperformance study of an algebraic multilevel sub-structuring (AMLS)method for sparse eigenvalue problems. We assess the time and memoryrequirements associated with the key steps of the algorithm, and compareitwith the shift-and-invert Lanczos algorithm in computational cost. Oureigenvalue problems come from two very different application areas: theaccelerator cavity design and the normal mode vibrational analysis of thepolyethylene particles.… more
Date: February 14, 2006
Creator: Gao, Weiguo; Li, Xiaoye S.; Yang, Chao & Bai, Zhaojun
Partner: UNT Libraries Government Documents Department
open access

Preliminary Evaluation of a Portable Handheld Combined Gamma and Neutron Directional Isotopic Identifying Detector

Description: Purpose: To simulate the performance of a portable dual gamma and neutron identification detector array with dual directional detection capability for preliminary algorithm evaluation. Experimental procedures: Monte Carlo N-Particle (MCNP) analysis on a compact array of borated polyvinyl toluene light pipes and photomultiplier tubes, standard spectral histogramming, and directional detection capability simulations. Results: Results demonstrate that the detector system is fully capable of correc… more
Date: February 14, 2008
Creator: Hayes, Robert
Partner: UNT Libraries Government Documents Department
open access

R-LODs: Fast LOD-Based Ray Tracing of Massive Models

Description: We present a novel LOD (level-of-detail) algorithm to accelerate ray tracing of massive models. Our approach computes drastic simplifications of the model and the LODs are well integrated with the kd-tree data structure. We introduce a simple and efficient LOD metric to bound the error for primary and secondary rays. The LOD representation has small runtime overhead and our algorithm can be combined with ray coherence techniques and cache-coherent layouts to improve the performance. In practice… more
Date: February 14, 2006
Creator: Yoon, S.; Lauterbach, C. & Manocha, D.
Partner: UNT Libraries Government Documents Department
open access

Development of the Low Swirl Injector for Fuel-Flexible Gas Turbines

Description: Industrial gas turbines are primarily fueled with natural gas. However, changes in fuel cost and availability, and a desire to control carbon dioxide emissions, are creating pressure to utilize other fuels. There is an increased interest in the use of fuels from coal gasification, such as syngas and hydrogen, and renewable fuels, such as biogas and biodiesel. Current turbine fuel injectors have had years of development to optimize their performance with natural gas. The new fuels appearing on t… more
Date: February 14, 2007
Creator: Littlejohn, D.; Cheng, R.K.; Nazeer,W.A. & Smith, K.O
Partner: UNT Libraries Government Documents Department
open access

Multiple time-scale methods in particle simulations of plasmas

Description: This paper surveys recent advances in the application of multiple time-scale methods to particle simulation of collective phenomena in plasmas. These methods dramatically improve the efficiency of simulating low-frequency kinetic behavior by allowing the use of a large timestep, while retaining accuracy. The numerical schemes surveyed provide selective damping of unwanted high-frequency waves and preserve numerical stability in a variety of physics models: electrostatic, magneto-inductive, Darw… more
Date: February 14, 1985
Creator: Cohen, B.I.
Partner: UNT Libraries Government Documents Department
open access

Survey of Modes and Their Effects in ORMAK, ISX-A, and ISX-B

Description: A comparison of some features of the three tokamaks is given. The ORMAK and ISX-A have ceased operation. The ISX-B has completed a checkout phase with studies of circular, ohmically heated plasmas in which it performed much like ISX-A. Shaped and injection heated plasmas are being studied. Diagnostics for mode structures were the usual Mirnov loops for approx.B/sub theta/ and collimated soft x-ray detectors for the internal fluctuations approx.X. The approx.X measurements on ISX-A, and thus far… more
Date: February 14, 1979
Creator: Dunlap, J. L.; Burris, R. D.; Harris, J. H.; Navarro, A. P. & Pare, V. K.
Partner: UNT Libraries Government Documents Department
open access

New radiobiological findings bearing on the 1977 ICRP recommendations. [Sensitivity of mouse and monkey prenatal oocytes to chronic, low-dose, tritium exposure]

Description: Recent experiments on low-level irradiation during development raise questions relevant to ICRP Publication 26. Mice and monkeys were studied; the measured endpoint was the radiation-induced loss of female germ cells. Three issues are examined. The first is the numerical value of Q (quality factor) appropriate for low-energy beta rays. Comparisons of tritium with gamma radiation were made under conditions of chronic, low-level exposure, and the relative biological effectiveness (RBE) was found … more
Date: February 14, 1979
Creator: Dobson, R.L.
Partner: UNT Libraries Government Documents Department
open access

Application of probabilistic risk assessment methods to incinerator design and permitting

Description: The Consolidated Incineration Facility at the Savannah River Site is designed without emergency flue gas vents. The main components of this 18 million btu/hr facility are a rotary kiln and secondary combustion chamber, each with a code allowable internal pressure of 15 psig. The facility is designed to treat mixed waste. During the early stages of design it was judged on a qualitative basis that potential eventsthat might produce damaging overpressures were not credible. When these findings wer… more
Date: February 14, 1993
Creator: Brown, E.A.; McAfee, D.E. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Aabye, D.C. (Science Applications International Corp., Oak Ridge, TN (United States))
Partner: UNT Libraries Government Documents Department
open access

The Y-12 Plant No Rad-Added Program for off-site shipment of nonradioactive hazardous waste

Description: On May 17, 1991, the US Department of Energy (DOE) issued a directive for DOE operations to cease off-site shipments of non-radioactive hazardous waste pending further clarification and approvals. A DOE Performance Objective for Certification of Non-Radioactive Hazardous Waste was issued in November 1991. In response to these directives, the Waste Management Division of Oak Ridge Y-12 Plant, with assistance from Roy F. Weston, Inc., has developed a No Rad-Added Program to provide small programm… more
Date: February 14, 1994
Creator: Cooper, K. H.; Mattie, B. K.; Williams, J. L.; Jacobs, D. G. & Roberts, K. A.
Partner: UNT Libraries Government Documents Department
open access

Application of probabilistic risk assessment methods to incinerator design and permitting

Description: The Consolidated Incineration Facility at the Savannah River Site is designed without emergency flue gas vents. The main components of this 18 million btu/hr facility are a rotary kiln and secondary combustion chamber, each with a code allowable internal pressure of 15 psig. The facility is designed to treat mixed waste. During the early stages of design it was judged on a qualitative basis that potential eventsthat might produce damaging overpressures were not credible. When these findings wer… more
Date: February 14, 1993
Creator: Brown, E. A.; McAfee, D. E. & Aabye, D. C.
Partner: UNT Libraries Government Documents Department
open access

Automatic Generation of Data Types for Classification of Deep Web Sources

Description: A Service Class Description (SCD) is an effective meta-data based approach for discovering Deep Web sources whose data exhibit some regular patterns. However, it is tedious and error prone to create an SCD description manually. Moreover, a manually created SCD is not adaptive to the frequent changes of Web sources. It requires its creator to identify all the possible input and output types of a service a priori. In many domains, it is impossible to exhaustively list all the possible input and o… more
Date: February 14, 2005
Creator: Ngu, A. H.; Buttler, D. J. & Critchlow, T. J.
Partner: UNT Libraries Government Documents Department
open access

NARAC Modeling During the Response to the Fukushima Dai-ichi Nuclear Power Plant Emergency

Description: This paper summarizes the activities of the National Atmospheric Release Advisory Center (NARAC) during the Fukushima Dai-ichi nuclear power plant crisis. NARAC provided a wide range of products and analyses as part of its support including: (1) Daily Japanese weather forecasts and hypothetical release (generic source term) dispersion predictions to provide situational awareness and inform planning for U.S. measurement data collection and field operations; (2) Estimates of potential dose in Jap… more
Date: February 14, 2012
Creator: Sugiyama, G.; Nasstrom, J. S.; Probanz, B.; Foster, K. T.; Simpson, M.; Vogt, P. et al.
Partner: UNT Libraries Government Documents Department
open access

THERMAL ANALYSIS OF A 9975 PACKAGE IN A FACILITY FIRE ACCIDENT

Description: Surplus plutonium bearing materials in the U.S. Department of Energy (DOE) complex are stored in the 3013 containers that are designed to meet the requirements of the DOE standard DOE-STD-3013. The 3013 containers are in turn packaged inside 9975 packages that are designed to meet the NRC 10 CFR Part 71 regulatory requirements for transporting the Type B fissile materials across the DOE complex. The design requirements for the hypothetical accident conditions (HAC) involving a fire are given in… more
Date: February 14, 2011
Creator: Gupta, N.
Partner: UNT Libraries Government Documents Department
open access

CONTAINMENT VESSEL TEMPERATURE FOR PU-238 HEAT SOURCE CONTAINER UNDER AMBIENT, FREE CONVECTION AND LOW EMISSIVITY COOLING CONDITIONS

Description: The EP-61 primary containment vessel of the 5320 shipping package has been used for storage and transportation of Pu-238 plutonium oxide heat source material. For storage, the material in its convenience canister called EP-60 is placed in the EP-61 and sealed by two threaded caps with elastomer O-ring seals. When the package is shipped, the outer cap is seal welded to the body. While stored, the EP-61s are placed in a cooling water bath. In preparation for welding, several containers are remove… more
Date: February 14, 2011
Creator: Gupta, N. & Smith, A.
Partner: UNT Libraries Government Documents Department
open access

The DEEP2 Galaxy Redshift Survey: The Voronoi-Delaunay Method Catalog of Galaxy Groups

Description: We use the first 25% of the DEEP2 Galaxy Redshift Survey spectroscopic data to identify groups and clusters of galaxies in redshift space. The data set contains 8370 galaxies with confirmed redshifts in the range 0.7 {<=} z {<=} 1.4, over one square degree on the sky. Groups are identified using an algorithm (the Voronoi-Delaunay Method) that has been shown to accurately reproduce the statistics of groups in simulated DEEP2-like samples. We optimize this algorithm for the DEEP2 survey by … more
Date: February 14, 2012
Creator: Gerke, Brian F.; Newman, Jeffrey A.; Davis, Marc; Marinoni, Christian; Yan, Renbin; Coil, Alison L. et al.
Partner: UNT Libraries Government Documents Department
open access

Branching Fraction Measurements of the Color-Suppressed Decays B0bar to D(*)0 pi0, D(*)0 eta, D(*)0 omega, and D(*)0 eta_prime and Measurement of the Polarization in the Decay B0bar to D*0 omega

Description: We report updated branching fraction measurements of the color-suppressed decays {bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}, D*{sup 0}{pi}{sup 0}, D{sup 0}{eta}, D*{sup 0}{eta}, D{sup 0}{omega}, D*{sup 0}{omega}, D{sup 0}{eta}', and D*{sup 0}{eta}'. We measure the branching fractions (x10{sup -4}): {Beta}({bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}) = 2.69 {+-} 0.09 {+-} 0.13, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{pi}{sup 0}) = 3.05 {+-} 0.14 {+-} 0.28, {Beta}({bar B}{sup 0} {yields} D{sup … more
Date: February 14, 2012
Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Issues in Equation of State data generation for Hot Dense MatterA Note on Generalized Radial Mesh Generation for Plasma Electronic Structure

Description: Precise electronic structure calculations of ions in plasmas benefit from optimized numerical radial meshes. A new closed form expression for obtaining non-linear parameters for the efficient generation of analytic log-linear radial meshes is presented. In conjunction with the (very simple) algorithm for the rapid high precision evaluation of Lambert's W-function, the above identity allows the precise construction of generalized log-linear radial meshes adapted to various constraints.
Date: February 14, 2011
Creator: Wilson, B G & Sonnad, V
Partner: UNT Libraries Government Documents Department
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