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Application of Moments Method to Dynamics of Muon Cooling System (open access)

Application of Moments Method to Dynamics of Muon Cooling System

This report talks about Application of Moments Method to Dynamics of Muon Cooling System
Date: December 3, 1996
Creator: Parsa, Z. & Zenkevich ,P.
System: The UNT Digital Library
Kinetics of Muon Longitudial Cooling (open access)

Kinetics of Muon Longitudial Cooling

None
Date: December 3, 1996
Creator: Parsa, Z. & Zenkevich, P.
System: The UNT Digital Library
Hanford prototype corrosion probe operational experience (open access)

Hanford prototype corrosion probe operational experience

High-level nuclear wastes at the Hanford Site are stored underground in carbon steel double-shell and single-shell tanks. The installation of a prototype corrosion monitoring system into double- shell tank 241-AZ-101 was completed in August, 1996. The system monitors fluctuations in corrosion current and potential (electrochemical noise) occurring on three electrode arrays immersed in the waste liquid and in the vapor space above the waste. The system also supports the use of Tafel and linear polarization resistance testing. By monitoring and analyzing the data from these techniques, changes; in the corrosive characteristics of the waste have been rapidly detected and correlated with operational changes in the tank.
Date: October 3, 1996
Creator: Edgemon, G.L.
System: The UNT Digital Library
Estimate of air carrier and air taxi crash frequencies from high altitude en route flight operations (open access)

Estimate of air carrier and air taxi crash frequencies from high altitude en route flight operations

In estimating the frequency of an aircraft crashing into a facility, it has been found convenient to break the problem down into two broad categories. One category estimates the aircraft crash frequency due to air traffic from nearby airports, the so-called near-airport environment. The other category estimates the aircraft crash frequency onto facilities due to air traffic from airways, jet routes, and other traffic flying outside the near-airport environment The total aircraft crash frequency is the summation of the crash frequencies from each airport near the facility under evaluation and from all airways, jet routes, and other traffic near the facility of interest. This paper will examine the problems associated with the determining the aircraft crash frequencies onto facilities outside the near-airport environment. This paper will further concentrate on the estimating the risk of aircraft crashes to ground facilities due to high altitude air carrier and air taxi traffic. High altitude air carrier and air taxi traffic will be defined as all air carrier and air taxi flights above 18,000 feet Mean Sea Level (MSL).
Date: June 3, 1996
Creator: Sanzo, D.; Kimura, C.Y. & Prassinos, P.G.
System: The UNT Digital Library
Melter system technology testing for Hanford Site low-level tankwaste vitrification (open access)

Melter system technology testing for Hanford Site low-level tankwaste vitrification

Following revisions to the Tri-Party Agreement for Hanford Site cleanup, which specified vitrification for Complete melter feasibility and system operability immobilization of the low-level waste (LLW) tests, select reference melter(s), and establish reference derived from retrieval and pretreatment of the radioactive LLW glass formulation that meets complete systems defense wastes stored in 177 underground tanks, commercial requirements (June 1996). Available melter technologies were tested during 1994 to 1995 as part of a multiphase program to select reference Submit conceptual design and initiate definitive design technologies for the new LLW vitrification mission.
Date: May 3, 1996
Creator: Wilson, C. N.
System: The UNT Digital Library
Dynamic simulation of the Hanford tank waste remediation system (open access)

Dynamic simulation of the Hanford tank waste remediation system

Cleaning up and disposing of approximately 50 years of nuclear waste is the main mission at the U.S. Department of Energy`s Hanford Nuclear Reservation, located in the southeastern part of the state of Washington. A major element of the total cleanup effort involves retrieving, processing, and disposing of radioactive and hazardous waste stored in 177 underground storage tanks. This effort, referred to as the Tank Waste Remediation System (TWRS), is expected to cost billions of dollars and take approximately 25 years to complete. Several computer simulations of this project are being created, focusing on both programmatic and detailed engineering issues. This paper describes one such simulation activity, using the ithink(TM)computer simulation software. The ithink(TM) simulation includes a representation of the complete TWRS cleanup system, from retrieval of waste through intermediate processing and final vitrification of waste for disposal. Major issues addressed to date by the simulation effort include the need for new underground storage tanks to support TWRS activities, and the estimated design capacities for various processing facilities that are required to support legally mandated program commitment dates. This paper discusses how the simulation was used to investigate these questions.
Date: May 3, 1996
Creator: Harmsen, R. W.
System: The UNT Digital Library
Development and testing of spheroidal inorganic sorbents (open access)

Development and testing of spheroidal inorganic sorbents

Objective was to develop sodium titanate (ST) microspheres, made by the HMTA (hexamethylenetetramine) internal gelation process, to remove radionuclides and heavy metals from waste streams at DOE sites. to determine the optimum amount of ST that can be embedded in hydrous Ti oxide (HTO) microspheres, batches of 9.2 to 23.3% ST in HTO were prepared. Crush strength of the air-dried microspheres was found to be highest. Sr was removed from simulated supernatant by all composite microspheres; 13.2% ST/HTO worked best.
Date: December 3, 1996
Creator: Collins, J.L.; Egan, B.Z. & Anderson, K.K.
System: The UNT Digital Library
Spin physics at RHIC a new twist on the heavy ion experiments (open access)

Spin physics at RHIC a new twist on the heavy ion experiments

Operation of RHIC with two beams of highly polarized protons (70%, either longitudinal or transverse) at high luminosity ???? = 2 {circ} 10{sup 32} cm{sup -2} sec{sup -1} for two months/year will allow high statistics studies of polarization phenomena in the perturbative region of hard scattering where both QCD and ElectroWeak theory make detailed predictions for polarization effects. The collision c.m energy, {radical}s = 200 - 500 GeV, represents a new domain for the study of spin. Direct photon production win be used to measure the gluon polarization in the polarized proton. A new twist comes from W-boson production which is expected to be 100% parity violating and will thus allow measurements of flavor separated quark and antiquark (u, u, d, d) polarization distributions. Searches for parity violation in strong interaction processes such as jet and leading particle production will be a sensitive way to look for new physics beyond the standard model, one possibility being quark substructure.
Date: July 3, 1996
Creator: Tannenbaum, Michael J.
System: The UNT Digital Library
Lifetime measurements and identical SD bands in the A=190 and A=150 regions (open access)

Lifetime measurements and identical SD bands in the A=190 and A=150 regions

The lifetimes of states in Superdeformed (SD) bands in {sup 192, 194}Hg, {sup 151,152}Dy, and {sup 151}Tb have been measured using the Doppler shift attenuation method. Intrinsic quadrupole moments Q{sub 0} have been extracted for SD bands in these nuclei. It was found that the quadrupole moments for the ``identical`` SD bands in these nuclei are the same. In the A = 150 region, changes were found in the Q{sub 0} values as a function of the number of high-N intruder orbitals. Changes are present also for excited SD bands with the same high-N content. Recent calculations account for most of the observations in the A = 150 region.
Date: September 3, 1996
Creator: Moore, E. F.; Nisius, D. & Janssens, R. V. F.
System: The UNT Digital Library
Superlinear convergence of an interior-point method for monotone variational inequalities (open access)

Superlinear convergence of an interior-point method for monotone variational inequalities

We describe an infeasible-interior-point algorithm for monotone variational inequality problems and prove that it converges globally and superlinearly under standard conditions plus a constant rank constraint qualification. The latter condition represents a generalization of the two types of assumptions made in existing superlinear analyses; namely, linearity of the constraints and linear independence of the active constraint gradients.
Date: January 3, 1996
Creator: Ralph, D. & Wright, S.
System: The UNT Digital Library
A novel method for diagnosing the growth of subresolution-scale perturbations (open access)

A novel method for diagnosing the growth of subresolution-scale perturbations

We have demonstrated a technique for diagnosing the growth of subresolution-scale perturbations by the appearance of longer-wavelength, coupled modes once the growth has proceeded into the nonlinear regime. Comparison of the growth rate of this larger scale feature with numerical simulations can then be used to infer the growth rates of the initial perturbations. This experiment was conceived as an analog of large-scale computer simulations where the large eddy approximation is applied. There a subgrid-scale model is used to represent the effects of small scales on large-scale motion, which is directly numerically simulated.
Date: May 3, 1996
Creator: Budil, K. S.; Remington, B. A. & Perry, T. S.
System: The UNT Digital Library
Development and characterization of a CCD camera system for use on six-inch manipulator systems (open access)

Development and characterization of a CCD camera system for use on six-inch manipulator systems

The Lawrence Livermore National Laboratory has designed, constructed, and fielded a compact CCD camera system for use on the Six Inch Manipulator (SIM) at the Nova laser facility. The camera system has been designed to directly replace the 35 mm film packages on all active SIM-based diagnostics. The unit`s electronic package is constructed for small size and high thermal conductivity using proprietary printed circuit board technology, thus reducing the size of the overall camera and improving its performance when operated within the vacuum environment of the Nova laser target chamber. The camera has been calibrated and found to yield a linear response, with superior dynamic range and signal-to-noise levels as compared to T-Max 3200 optic film, while providing real-time access to the data. Limiting factors related to fielding such devices on Nova will be discussed, in addition to planned improvements of the current design.
Date: May 3, 1996
Creator: Logory, L. M.; Bell, P. M.; Conder, A. D. & Lee, F. D.
System: The UNT Digital Library
Improved assessment of aviation hazards to ground facilities using a geographical information system (open access)

Improved assessment of aviation hazards to ground facilities using a geographical information system

A computer based system for performing probabilistic safety assessments (PSAs) of aircraft crashes to ground structures is under development. The system called ACRA (aircraft crash risk assessment) employs a GIS (geographical information system) for locating, mapping, and characterizing ground structures; and a multiparameter data base system that supports the analytical PRA (probabilistic risk assessment) model for determining PSAs for aircraft crashes. The Salt Lake City International Airport (SLC) is being employed as the base case for study and application of ACRA and evaluation of the projected safety assessment.
Date: June 3, 1996
Creator: Sandquist, G. M.; Slaughter, D. M. & Kimura, C. Y.
System: The UNT Digital Library
Azimuthal correlations of transverse energy for Pb on Pb at 158 GeV/nucleon (open access)

Azimuthal correlations of transverse energy for Pb on Pb at 158 GeV/nucleon

Azimuthal correlations have been studied in heavy ion reactions over a wide range of beam energies. At low incident energies up to 100 MeV/nucleon where collective effects like the directed sidewards flow are generally small, azimuthal correlations provide a useful tool to determine the reaction plane event by event. In the energy regime of the BEVALAC (up to 1 GeV/nucleon for heavy ions) particular emission patterns, i.e. azimuthal correlations of nucleons and light nuclei with respect to the reaction plane, have been associated with the so called squeeze out and sidesplash effects. These effects are of particular interest because of their sensitivity to the equation of state at the high baryon density which is build up during the collision process. Angular distributions similar to the squeeze out have been observed for pions at the SIS in Darmstadt as well as from the EOS - collaboration. Recently also the sideward flow was measured for pions and kaons. However, the origin of the signal in the case of produced mesons is thought to be of a different nature than that for the nucleon flow. At the AGS, azimuthally anisotropic event shapes have been reported from the E877 collaboration for the highest available …
Date: February 3, 1996
Creator: Wienold, T.; Huang, I. & Collaboration, The NA49
System: The UNT Digital Library
Catastrophic failure of contaminated fused silica optics at 355 nm (open access)

Catastrophic failure of contaminated fused silica optics at 355 nm

For years, contamination has been known to degrade the performance of optics and to sometimes initiate laser-induced damage to initiate. This study has W to quantify these effects for fused silica windows used at 355 mm Contamination particles (Al, Cu, TiO{sub 2} and ZrO{sub 2}) were artificially deposited onto the surface and damage tests were conducted with a 3 ns NdYAG laser. The damage morphology was characterized by Nomarski optical microscopy. The results showed that the damage morphology for input and output surface contamination is different. For input surface contamination, both input and output surfaces can damage. In particular, the particle can induce pitting or drilling of the surface where the beam exits. Such damage usually grows catastrophically. Output surface contamination is usually ablated away on the shot but can also induce catastrophic damage. Plasmas are observed during illumination and seem to play an important role in the damage mechanism. The relationship between fluence and contamination size for which catastrophic damage occurred was plotted for different contamination materials. The results show that particles even as small as 10 {micro}m can substantially decrease the damage threshold of the window and that metallic particles on the input surface have a more negative …
Date: December 3, 1996
Creator: Genin, F. Y., LLNL
System: The UNT Digital Library
Low-cost multi-terrain autonomous vehicle for hostile environments (open access)

Low-cost multi-terrain autonomous vehicle for hostile environments

This paper describes an innovative and unique autonomous vehicle being developed at the Lawrence Livermore National Laboratory (LLNL) for versatile use in hostile environments. Conventional vehicles used in decommissioning and decontaminating, police activity, and unmanned military operations typically are designed with four-wheels or track in contact with the environment. Although four-wheel and track vehicles work well, they are limited in negotiating saturated terrain, steep hills and soft soils. The Spiral Track Autonomous Robot (STAR) is a versatile and maneuverable multi-terrain mobile vehicle that uses the latest available computer technology and two Archimedes screws, in contact with the local environment to intelligently negotiate a hostile environment.
Date: December 3, 1996
Creator: Perez, M. L., LLNL
System: The UNT Digital Library