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The Low-Energy State ofCirculating Stored Ion Beams: Crystalline Beams

Description: Molecular dynamics is employed to study the low energy states of a beam of charged particles subject to circumferentially varying guiding and focusing forces and with Coulomb forces between the particles. In a constant gradient ring, the lowest energy state is never ordered, but in an alternating gradient structure, operating below the transition energy, the lowest state is ordered. The nature and characteristics of the ground state depends upon the beam density and the ring parameters. For zer… more
Date: March 10, 1994
Creator: Wei, J.; Li, X. P. & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
open access

Liquid-vapor partitioning of NaCl(aq) from concentrated brines at temperatures to 350{degrees}C

Description: Compositions of coexisting liquid and vapor phases have been determined at temperatures from 250 to 350{degree}C for brines containing NaCl and either HCl or NaOH by direct sampling of both phases from a static phase-equilibration apparatus. Thermodynamic partitioning constants for NaCl have been determined from the observed compositions of the coexisting phases combined with the known activity coefficients of NaCl(aq) in the liquid phase. An apparent dependence of the values of these partition… more
Date: March 1, 1994
Creator: Simonson, J. M.; Palmer, D. A. & Carter, R. W.
Partner: UNT Libraries Government Documents Department
open access

Risk evaluation of medical and industrial radiation devices

Description: In 1991, the NRC, Division of Industrial and Medical Nuclear Safety, began a program to evaluate the use of probabilistic risk assessment (PRA) in regulating medical devices. This program represents an initial step in an overall plant to evaluate the use of PRA in regulating the use of nuclear by-product materials. The NRC envisioned that the use of risk analysis techniques could assist staff in ensuring that the regulatory approach was standardized, understandable, and effective. Traditional m… more
Date: March 1, 1994
Creator: Jones, E. D.; Cunningham, R. E. & Rathbun, P. A.
Partner: UNT Libraries Government Documents Department
open access

An autonomous mobil robot to perform waste drum inspections

Description: A mobile robot is being developed by the Savannah River Technology Center (SRTC) Robotics Group of Westinghouse Savannah River company (WSRC) to perform mandated inspections of waste drums stored in warehouse facilities. The system will reduce personnel exposure and create accurate, high quality documentation to ensure regulatory compliance. Development work is being coordinated among several DOE, academic and commercial entities in accordance with DOE`s technology transfer initiative. The prot… more
Date: March 1, 1994
Creator: Peterson, K. D. & Ward, C. R.
Partner: UNT Libraries Government Documents Department
open access

Adjacent-cell Preconditioners for solving optically thick neutron transport problems

Description: We develop, analyze, and test a new acceleration scheme for neutron transport methods, the Adjacent-cell Preconditioner (AP) that is particularly suited for solving optically thick problems. Our method goes beyond Diffusion Synthetic Acceleration (DSA) methods in that it`s spectral radius vanishes with increasing cell thickness. In particular, for the ID case the AP method converges immediately, i.e. in one iteration, to 10{sup {minus}4} pointwise relative criterion in problems with dominant ce… more
Date: March 1, 1994
Creator: Azmy, Y. Y.
Partner: UNT Libraries Government Documents Department
open access

Static analysis of a piping system with elbows

Description: Vibration tests of elbows to failure were performed in Japan in the early 1970s. The piping system included two elbows and an eccentric mass. Tests were run both pressurized and unpressurized. This report documents a static analysis of the piping system in which the elbows are subjected to out of plane bending. The effects of internal pressure and material plasticity are investigated.
Date: March 1, 1994
Creator: Bryan, B. J.
Partner: UNT Libraries Government Documents Department
open access

Vulnerability assessment of a space based weapon platform electronic system exposed to a thermonuclear weapon detonation

Description: Rapidly changing world events, the increased number of nations with inter-continental ballistic missile capability, and the proliferation of nuclear weapon technology will increase the number of nuclear threats facing the world today. Monitoring these nation`s activities and providing an early warning and/or intercept system via reconnaissance and surveillance satellites and space based weapon platforms is a viable deterrent against a surprise nuclear attack. However, the deployment of satellit… more
Date: March 1, 1994
Creator: Perez, C. L. & Johnson, J. O.
Partner: UNT Libraries Government Documents Department
open access

Gas phase decontamination of gaseous diffusion process equipment

Description: D&D of the process facilities at the gaseous diffusion plants (GDPs) will be an enormous task. The EBASCO estimate places the cost of D&D of the GDP at the K-25 Site at approximately $7.5 billion. Of this sum, nearly $4 billion is associated with the construction and operation of decontamination facilities and the dismantlement and transport of contaminated process equipment to these facilities. In situ long-term low-temperature (LTLT) gas phase decontamination is being developed and demonstrat… more
Date: March 1, 1994
Creator: Bundy, R. D.; Munday, E. B.; Simmons, D. W. & Neiswander, D. W.
Partner: UNT Libraries Government Documents Department
open access

The ATLAS Positron Experiment -- APEX

Description: APEX -- the ATLAS Positron Experiment -- is designed to measure electrons and positrons emitted in heavy-ion collisions. Its scientific goal is to gain insight into the puzzling positron-line phenomena observed at the GSI Darmstadt. It is in operation at the ATLAS accelerator at Argonne National Lab. The assembly of the apparatus is finished and beginning 1993 the first positrons produced in heavy-ion collisions were observed. The first full scale experiment was carried out in December 1993, an… more
Date: March 1, 1994
Creator: Ahmad, I.; Back, B. B.; Betts, R. R.; Dunford, R.; Kutschera, W.; Rhein, M. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Effect of the stimulated Brillouin backscattering on selffocusing threshold

Description: In many physical problems stimulated Brillouin scattering (SBS) and selffocusing are manifested simultaneously. We consider effect of the stimulated Brillouin backscattering (SBS) on self-focusing of laser radiation in plasmas. It was found that the self-focusing may be supressed substantionally by the SBS effect.
Date: March 1, 1994
Creator: Rubenchik, A. M.; Shapiro, E. G. & Turitsyn, S. K.
Partner: UNT Libraries Government Documents Department
open access

Scenario development for the Waste Isolation Pilot Plant: Building confidence in the assessment

Description: Scenario developments is part of the iterative performance assessment (PA) process for the Waste Isolation Pilot Plant (WIPP). Scenario development for the WIPP has been the subject of intense external review, and is certain to be the subject of continued scrutiny as the project proceeds toward regulatory compliance. The principal means of increasing confidence is this aspect of the PA will be through the use of a systematic and thorough procedure toward developing the scenarios and conceptual … more
Date: March 1, 1994
Creator: Galson, D. A. & Swift, P. N.
Partner: UNT Libraries Government Documents Department
open access

Calculation of peak-to-total ratios for GE detector spectra

Description: We have measured many peak-to-total gamma-ray detection ratios for germanium detectors, and have correlated the observed values with various parameters, such as gamma-ray energy, detector size, source-to-detector distance, and shielding. We have also observed an unexpected, pronounced, positive slope in the peak-to-total curve in the low-energy region of p-type detectors. To explain this observation, we have evidence that the ``dead`` layer is not completely dead but is capable of producing deg… more
Date: March 1, 1994
Creator: Gunnink, R.; De Corte, F.; De Wispelaere, A.; Bossus, D.; van Sluijs, R. & Vervecken, D.
Partner: UNT Libraries Government Documents Department
open access

Robot trajectory planning via dynamic programming

Description: The method of dynamic programming is applied to three example problems dealing with robot trajectory planning. The first two examples involve end-effector tracking of a straight line with rest-to-rest motions of planar two-link and three-link rigid robots. These examples illustrate the usefulness of the method for producing smooth trajectories either in the presence or absence of joint redundancies. The last example demonstrates the use of the method for rest-to-rest maneuvers of a single-link … more
Date: March 1, 1994
Creator: Dohrmann, C. R. & Robinett, R. D.
Partner: UNT Libraries Government Documents Department
open access

Some effects of heat release in premixed flames

Description: Numerical and experimental results are presented to illustrate some hydrodynamic effects of heat release in premixed flames. The heat release is represented by a simple model which treats the flame front as a two dimensional line source of volume. The velocity and strain rate induced in the flow field are determined and the numerical solution for the case of a laminar double kernel ignition is obtained. Of primary interest is the strain induced in the reactants between the expanding flame kerne… more
Date: March 1, 1994
Creator: Shepherd, I. G.
Partner: UNT Libraries Government Documents Department
open access

VIM Monte Carlo versus CASMO comparisons for BWR advanced fuel designs

Description: Eigenvalues and two-dimensional fission rate distributions computed with the CASMO-3G lattice physics code and the VIM Monte Carlo Code are compared. The cases assessed are two advanced commercial BWR pin bundle designs. Generally, the two codes show good agreement in K{sub inf}, fission rate distributions, and control rod worths.
Date: March 1, 1994
Creator: Pallotta, A. S. & Blomquist, R. N.
Partner: UNT Libraries Government Documents Department
open access

New advances in the modeling of high-temperature superconductors

Description: In this paper, we present a new discrete formulation that maintains discrete invariance and is suitable for use on nonorthogonal meshes. This formulation, unlike its predecessors, allows us to easily use adaptive mesh refinement to concentrate grid points where error contributions are large (near vortex centers). In this way we reduce the total number of grid points required to accurately capture vortex configurations and allow the possibility of solving problems previously considered intractab… more
Date: March 1, 1994
Creator: Freitag, L.; Plassmann, P. & Jones, M.
Partner: UNT Libraries Government Documents Department
open access

The application of maximum entropy to Z-contrast imaging in a stem

Description: Maximum entropy (Gull and Skilling, IEE Proceedings, 131F, 646 (1984)) is an image processing routine based on Bauesian probability which can produce a ``most likely`` image from original data given a particular point spread function. By combining maximum entropy and analysis with incoherent Z-contrast imaging, it is possible to retrieve crystal lattice information at atomic resolution from directly acquired experimental data without the need for preconceived structures. Results are given for s… more
Date: March 1, 1994
Creator: McGibbon, A. J. & Pennycook, S. J.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of the cover cracking potential due to ground subsidence at UMTRA Project disposal cells

Description: The US Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project requires that mill tailings, containing low-level radioactive uranium mill tailings and other waste, be stabilized and controlled by placement in an encapsulated disposal cell. The cover of the cell is a multi-layer system which includes a low-permeability earthen radon/infiltration barrier, a bedding layer, and a erosion protection layer. The radon/infiltration barrier is designed to limit the radon flux and re… more
Date: March 1, 1994
Creator: Claire, R. F.; Kuo, J. C. & Wanket, D. R.
Partner: UNT Libraries Government Documents Department
open access

Estimating low-dose rate irradiation response of MOSFETs

Description: A simple method to estimate the threshold-voltage shift in MOSFETs due to low-dose-rate ionizing irradiation based on MIL-STD-883D Method 1019.4 is demonstrated. The realm of applicability of this approach is explored.
Date: March 1, 1994
Creator: Khosropour, P.; Galloway, K. F.; Schrimpf, R. D.; Fleetwood, D. M. & Calvel, P.
Partner: UNT Libraries Government Documents Department
open access

Analysis of environmental regulatory proposals: Its your chance to influence policy

Description: As part of the regulatory development process, the US Envirorunental Protection Agency (EPA) collects data, makes various assumptions about the data, and analyzes the data. Although EPA acts in good faith, the agency cannot always be aware of all relevant data, make only appropriate assumptions, and use applicable analytical methods. Regulated industries must carefully must carefully review every component of the regulatory decision-making process to identify misunderstandings and errors and to… more
Date: March 2, 1994
Creator: Veil, J. A.
Partner: UNT Libraries Government Documents Department
open access

Impact of reducing sodium void worth on the severe accident response of metallic-fueled sodium-cooled reactors

Description: Analyses have performed on the severe accident response of four 90 MWth reactor cores, all designed using the metallic fuel of the Integrated Fast Reactor (IFR) concept. The four core designs have different sodium void worth, in the range of {minus}3$ to 5$. The purpose of the investigation is to determine the improvement in safety, as measured by the severe accident consequences, that can be achieved from a reduction in the sodium void worth for reactor cores designed using the IFR concept.
Date: March 1, 1994
Creator: Wigeland, R. A.; Turski, R. B. & Pizzica, P. A.
Partner: UNT Libraries Government Documents Department
open access

Defining the role of risk assessment in the comprehensive environmental response compensation and liability act remedial investigation process at the DOE-OR

Description: Cleanup of hazardous waste sites under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) is a complicated and painstaking process, particularly at facilities with a multitude of individual hazardous waste sites, each having a multitude of chemicals and radonuclides. The US Department of Energy-Oak Ridge, Environmental Restoration Division (DOE-OR/ERD) administers five such facilities which are undergoing environmental cleanup under the CERCLA Remedial Investigat… more
Date: March 8, 1994
Creator: Miller, P. D.; McGinn, C. W.; White, R. K.; Purucker, S. T. & Redfearn, A.
Partner: UNT Libraries Government Documents Department
open access

Wave packet studies of the vibrational predissociation of three and four-atom van der Waals complexes

Description: Vibrational predissociation of XI{sub 2} and X{sub 2}I{sub 2} van der Waals complexes, with X = He and Ne, is studied with wave packets. Three-dimensional calculations are carried out on the three-atom systems. Suitable X{center_dot}{center_dot}I potential interactions are determined, and product distributions are predicted. Reduced dimension models of X{sub 2}I{sub 2}(v{prime}) {yields} 2X + I{sub 2}(v < v{prime}) are investigated. Comparison is made with available experimental results. Mechan… more
Date: March 1, 1994
Creator: Gray, S. K.
Partner: UNT Libraries Government Documents Department
open access

Precise measurement of the left-right cross section asymmetry in Z boson production by electron-positron collisions

Description: A precise measurement of the left-right cross section asymmetry (A{sub LR}) for Z boson production by e{sup +}e{sup {minus}} collisions has been attained at the Slac Linear Collider with the SLD detector. We describe this measurement for the 1993 data run, emphasizing the significant improvements in polarized beam operation which took place for this run, where the luminosity-weighted electron beam polarization averaged 62.6 {plus_minus} 1.2 %. Preliminary 1993 results for A{sub LR} are presente… more
Date: March 1, 1994
Creator: Frey, R. E.
Partner: UNT Libraries Government Documents Department
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