Resource Type

Why are the P{sub n} and S{sub n} Methods Equivalent (open access)

Why are the P{sub n} and S{sub n} Methods Equivalent

The author assumes that the reader is familiar with the Spherical harmonics, Pn, method and the discrete ordinates, S{sub n}, method; for a derivation of the equations used in these methods. I will only discuss the Boltzmann equation in one dimension, and the Sn method using Gaussian quadrature. I will do this merely to simplify the following discussion; once you understand the concepts presented here you can easily extend the conclusions to more general situations. Why are the spherical harmonics P{sub n} and discrete ordinate S{sub n} methods, or more correctly the P{sub n} and S{sub n+1} methods, equivalent, e.g., P{sub 3} is equivalent to S{sub 4}? When the S{sub n} method uses a Gaussian quadrature most textbooks will tell you that both methods are equivalent to assuming that the angular flux can be represented by a Legendre polynomial expansion of order n. Most textbooks are wrong [1]. We know that the S{sub n} method constrains the ''particles'' to travel in discrete directions; when Gaussian quadrature is used these discrete directions correspond to the zeros of the Legendre polynomial P{sub n+1}({mu}). What is not immediately obvious is that the P{sub n} method constrains the ''particles'' in exactly the same way. …
Date: September 19, 2001
Creator: Cullen, D E
System: The UNT Digital Library
Effects of pressure and saturation on seismic velocities and impedance measurements (open access)

Effects of pressure and saturation on seismic velocities and impedance measurements

Two synthetic data sets were examined to study the possible methods for distinguishing the effects of changes in saturation, and changes in pore pressure, on seismic velocity and impedance measurements. The results show that the results obtained previously on the dependence of laboratory velocity data on changes in saturation carry over without change to the data in these data sets. The assumption in this case is that the only data available are the seismic velocities. This situation can arise in cross-well seismic tomography. Of more direct interest to this project is how these methods and results should change when the data are instead seismic impedance measurements. The main conclusions are that the most appropriate plotting methods for seismic impedance data in order to distinguish changes in saturation, changes in pressure, and saturation changes from pressure changes are ({rho}{mu}, {lambda}/{mu}) and ({mu}/{lambda}, {rho}{mu}{sup 2}/{lambda}). All of these plotting coordinates can be computed easily from the impedance data {rho}{nu}{sub p} and {rho}{nu}{sub s}, since {rho}{mu} = ({rho}{nu}{sub s}){sup 2}, and {rho}{lambda} = ({rho}{nu}{sub p}){sup 2} - 2({rho}{nu}{sub s}){sup 2}, while {lambda}/{mu} = {rho}{lambda}/{rho}{mu} and {rho}{mu}{sup 2}/{lambda} = ({rho}{mu}){sup 2}/{rho}{lambda}. These choices are not the only possibilities, but they seem to give the …
Date: January 18, 2001
Creator: Berryman, James G.
System: The UNT Digital Library
H2O Outgassing In and Its Effects on M9787 Silicone (open access)

H2O Outgassing In and Its Effects on M9787 Silicone

Temperature programmed desorption (TPD) was performed on M9787 silicone, Cab-O-Sil-M-7D (fumed) and Hi-Sil-233 (precipitated) silica particles that had been annealed to 460 K for 24 hours then exposed to different moisture levels. Our results suggest that moisture desorption and adsorption in M9787 can be approximated by the interaction of its silica contents (Cab-O-Sil-M-7D and Hi-Sil-233) with moisture. Our experimental data also reveal that, in general, as heat treated silica particles are exposed to moisture, chemisorbed states, then physisorbed states are gradually filled up in that order. However, there seems to have some rearrangement of bonds as moisture desorbs or absorbs on the surfaces of the silica particles. Nanoindentation was also performed on M9787 silicones that were simultaneously pumped down to a few hundred Pa of residual pressure at room temperature. Our data shows that the removal of physisorbed water in M9787 has none or reversible little effect on the mechanical properties of M9787.
Date: September 1, 2001
Creator: Dinh, L N; Schildbach, M A; McLean, W; Balazs, B; LeMay, J D & Balooch, M
System: The UNT Digital Library
Accounting Data to Web Interface Using PERL (open access)

Accounting Data to Web Interface Using PERL

This document will explain the process to create a web interface for the accounting information generated by the High Performance Storage Systems (HPSS) accounting report feature. The accounting report contains useful data but it is not easily accessed in a meaningful way. The accounting report is the only way to see summarized storage usage information. The first step is to take the accounting data, make it meaningful and store the modified data in persistent databases. The second step is to generate the various user interfaces, HTML pages, that will be used to access the data. The third step is to transfer all required files to the web server. The web pages pass parameters to Common Gateway Interface (CGI) scripts that generate dynamic web pages and graphs. The end result is a web page with specific information presented in text with or without graphs. The accounting report has a specific format that allows the use of regular expressions to verify if a line is storage data. Each storage data line is stored in a detailed database file with a name that includes the run date. The detailed database is used to create a summarized database file that also uses run date …
Date: August 13, 2001
Creator: Hargeaves, C
System: The UNT Digital Library
Multi-Scale Thermohydrologic Model Sensitivity-Study Calculations in Support of the SSPA (open access)

Multi-Scale Thermohydrologic Model Sensitivity-Study Calculations in Support of the SSPA

The purpose of this calculation report is to document the thermohydrologic (TH) model calculations performed for the Supplemental Science and Performance Analysis (SSPA), Volume 1, Section 5 and Volume 2 (BSC 2001d [DIRS 155950], BSC 2001e [DIRS 154659]). The calculations are documented here in accordance with AP-3.12Q REV0 ICN4 [DIRS 154418]. The Technical Working Plan (Twp) for this document is TWP-NGRM-MD-000015 Real. These TH calculations were primarily conducted using three model types: (1) the Multiscale Thermohydrologic (MSTH) model, (2) the line-averaged-heat-source, drift-scale thermohydrologic (LDTH) model, and (3) the discrete-heat-source, drift-scale thermal (DDT) model. These TH-model calculations were conducted to improve the implementation of the scientific conceptual model, quantify previously unquantified uncertainties, and evaluate how a lower-temperature operating mode (LTOM) would affect the in-drift TH environment. Simulations for the higher-temperature operating mode (HTOM), which is similar to the base case analyzed for the Total System Performance Assessment for the Site Recommendation (TSPA-SR) (CRWMS M&O 2000j [DIRS 153246]), were also conducted for comparison with the LTOM. This Calculation Report describes (1) the improvements to the MSTH model that were implemented to reduce model uncertainty and to facilitate model validation, and (2) the sensitivity analyses conducted to better understand the influence of parameter …
Date: December 20, 2001
Creator: Glascoe, L G; Buscheck, T A; Loosmore, G A & Sun, Y
System: The UNT Digital Library
Diagnostic Systems Approach to Watershed Management (open access)

Diagnostic Systems Approach to Watershed Management

The water quality of discharge from the surface water system is ultimately dictated by land use and climate within the watershed. Water quality has vastly improved from point source reduction measures, yet, non-point source pollutants continue to rise. 30 to 40% of rivers still do not meet water quality standards for reasons that include impact from urban storm water runoff, agricultural and livestock runoff, and loss of wetlands. Regulating non-point source pollutants proves to be difficult since specific dischargers are difficult to identify. However, parameters such as dissolved organic carbon (DOC) limit the amounts of chlorination due to simultaneous disinfection by-product formation. The concept of watershed management has gained much ground over the years as a means to resolve non-point source problems. Under this management scheme stakeholders in a watershed collectively agree to the nature and extent of non-point sources, determine water quality causes using sound scientific approaches, and together develop and implement a corrective plan. However, the ''science'' of watershed management currently has several shortcomings according to a recent National Research Council report. The scientific component of watershed management depends on acquiring knowledge that links water quality sources with geographic regions. However, there is an observational gap in this …
Date: February 23, 2001
Creator: Davisson, M L
System: The UNT Digital Library
Analysis of Fabry-Perot Velocimeter Records (open access)

Analysis of Fabry-Perot Velocimeter Records

Program demonstration and user instructions are presented for FabryVB5. This computer program was created for use in analyzing Fabry-Perot interferometer records that detail the velocity time histories of fast moving surfaces. Graphical curves representing peak fringe positions and fiducial timing dots are extracted from a digitized film record or from a CCD digital image. An analysis is demonstrated on a sample velocimeter record along with some mathematical formula and routine operations. Routines used to analyze calibration records on streak camera distortions are illustrated in an appendix. This is a Microsoft Visual Basic{trademark} version for the PC.
Date: August 3, 2001
Creator: Avara, G.
System: The UNT Digital Library
ERA-40 SST and Sea Ice Concentration Data (open access)

ERA-40 SST and Sea Ice Concentration Data

The lower boundary condition of sea surface temperature (SST) and sea-ice concentration (sic) is a critical forcing of the lower frequencies in multi-decadal global atmospheric reanalyses such as ERA-40. Partly in response to the ERA-40 project, new SST/sic data sets have been developed that are considerably improved over those available to the first-generation reanalyses. This paper documents the input SST/sic data sets and the processing that created the daily SST/sic specification for the ERA-40 period 1956-2001. The source data are: (1) the monthly mean HadISST data set from the UKMO Hadley Centre for 1956-1981; and (2) the weekly NCEP 2DVAR data for 1982-present. Both data sets are reanalyses of satellite and conventional SST/sic observations. The principal reason for the higher quality of these source data sets is the use of a common consensus sic and a common sic-SST relationship in the sea ice margins. The use of a common sic resulted in a very smooth transition between HadISST and NCEP 2DVAR, despite differences in data assimilation techniques and monthly versus weekly analyses. No special action was required to insure consistency at the transition unlike as was necessary for the AMIP II experiment (Fiorino, 1997). The only special processing was application …
Date: August 27, 2001
Creator: Fiorino, M
System: The UNT Digital Library
Rheological Studies on Pretreated Feed and Melter Feed from AW-101 and AN-107 (open access)

Rheological Studies on Pretreated Feed and Melter Feed from AW-101 and AN-107

Rheological and physical properties testing were conducted on actual AN-107 and AW-101 pretreated feed samples prior to the addition of glass formers. Analyses were repeated following the addition of glass formers. The AN-107 and AW-101 pretreated feeds were tested at the target sodium values of nominally 6, 8, and 10 M. The AW-101 melter feeds were tested at these same concentrations, while the AN-107 melter feeds were tested at 5, 6, and 8 M with respect to sodium. These data on actual waste are required to validate and qualify results obtained with simulants.
Date: February 6, 2001
Creator: Bredt, Paul R. (BATTELLE (PACIFIC NW LAB)) & Swoboda, Robert G. (BATTELLE (PACIFIC NW LAB))
System: The UNT Digital Library
Shielding Calculations for the BDMS UF6 Mass Flow Meter (open access)

Shielding Calculations for the BDMS UF6 Mass Flow Meter

We performed Monte Carlo calculations of the neutron and gamma ray spectra and neutron and gamma dose rates outside the shielding of the UF{sub 6} mass flowmeter. The UF{sub 6} mass flowmeter and the UF{sub 6} mass flowmeter are the two main components of the Blend Down Monitoring System (BDMS) equipment. The BDMS equipment is designed to continuously monitor the UF{sub 6} enrichment and mass flow rates in processing pipes at uranium facilities. The UF{sub 6} mass flowmeter incorporates four {sup 252}Cf neutron sources, surrounded by a polyethylene shielding block. The uranium fission products generated by the {sup 252}Cf neutrons are detected down the pipe, thus confirming the UF{sub 6} mass flow rate. The dose calculations used both U.S. and Russian gamma and neutron fluence-to-dose conversion coefficients. The purpose of these calculations was to facilitate proper interpretation of the neutron dose rate measurements from rem meters (e.g., rem balls) outside of BDMS shielding. An accurate determination of the dose rate is particular interest in that it enables dose rates to be compared with the applicable regulatory limit. The calculations show that neutrons outside of BDMS shielding are significantly reduced in energy, i.e., the spectrum is shifted (i.e., moderated) towards lower …
Date: September 13, 2001
Creator: Radev, R & Hall, J
System: The UNT Digital Library
Science & Technology Review November 2001 (open access)

Science & Technology Review November 2001

None
Date: November 1, 2001
Creator: Quong, A
System: The UNT Digital Library
Plutonium Immobilization Project Development and Testing Baseline and Progress Monthly Report December 2000 (open access)

Plutonium Immobilization Project Development and Testing Baseline and Progress Monthly Report December 2000

None
Date: January 1, 2001
Creator: MacLean, L M
System: The UNT Digital Library
SEA - A Simplified Employee Assessment (open access)

SEA - A Simplified Employee Assessment

This paper presents a proposal for modifying the current employee annual evaluation process in SCAD. It purports to simplify that process, primarily by breaking up the resultant document into a set of more or less independent components. It claims to reduce the overall time and effort required from each actor.
Date: April 23, 2001
Creator: Busby, L
System: The UNT Digital Library
FY2002 Progress Summary Program Plan, Statement of Work and Deliverables for Development of High Average Power Diode-Pumped Solid State Lasers, and Complementary Technologies, for Applications in Energy and Defense (open access)

FY2002 Progress Summary Program Plan, Statement of Work and Deliverables for Development of High Average Power Diode-Pumped Solid State Lasers, and Complementary Technologies, for Applications in Energy and Defense

The High Average Power Laser Program (HAPL) is a multi-institutional, coordinated effort to develop a high-energy, repetitively pulsed laser system for Inertial Fusion Energy and other DOE and DOD applications. This program is building a laser-fusion energy base to complement the laser-fusion science developed by DOE Defense programs over the past 25 years. The primary institutions responsible for overseeing and coordinating the research activities are the Naval Research Laboratory (NRL) and LLNL. The current LLNL proposal is a companion proposal to that submitted by NRL, for which the driver development element is focused on the krypton fluoride excimer laser option. Aside from the driver development aspect, the NRL and LLNL companion proposals pursue complementary activities with the associated rep-rated laser technologies relating to target fabrication, target injection, final optics, fusion chamber, materials and power plant economics. This report requests continued funding in FY02 to support LLNL in its program to build a 1kW, 100J, diode-pumped, crystalline laser. In addition, research in high gain laser target design, fusion chamber issues and survivability of the final optic element will be pursued. These technologies are crucial to the feasibility of inertial fusion energy power plants and also have relevance in rep-rated stewardship experiments.
Date: December 13, 2001
Creator: Bayramian, A.; Bibeau, C.; Beach, R.; Behrendt, B.; Ebbers, C.; Latkowski, J. et al.
System: The UNT Digital Library
Mechanical properties of D0 Run IIB silicon detector staves (open access)

Mechanical properties of D0 Run IIB silicon detector staves

A proposed stave design for the D0 Run IIb silicon tracker outer layers featuring central cooling channels and a composite shell mechanical structure is evaluated for self-deflection and deflection due to external loads. This paper contains an introduction to the stave structure, a section devoted to composite lamina and laminate properties and finally a section discussing the beam deflections expected for assembled staves using these laminates.
Date: June 14, 2001
Creator: Lanfranco, Giobatta & Fast, James
System: The UNT Digital Library
Environmental Report 2000 (open access)

Environmental Report 2000

Lawrence Livermore National Laboratory (LLNL), a U.S. Department of Energy (DOE) facility operated by the University of California (UC), serves as a national resource of scientific, technical, and engineering capabilities. The Laboratory's mission focuses on nuclear weapons and national security, and over the years has been broadened to include areas such as strategic defense, energy, the environment, biomedicine, technology transfer, the economy, and education. The Laboratory carries out this mission in compliance with local, state, and federal environmental regulatory requirements. It does so with the support of the Environmental Protection Department, which is responsible for environmental monitoring and analysis, hazardous waste management, environmental restoration, and assisting Laboratory organizations in ensuring compliance with environmental laws and regulations. LLNL comprises two sites: the Livermore site and Site 300. The Livermore site occupies an area of 3.28 square kilometers on the eastern edge of Livermore, California. Site 300, LLNL's experimental testing site, is located 24 kilometers to the east in the Altamont Hills and occupies an area of 30.3 square kilometers. Meteorological and environmental monitoring activities are conducted at both sites as well as in surrounding areas. This summary provides an overview of LLNL's environmental activities in 2000, including radiological and nonradiological surveillance, …
Date: September 1, 2001
Creator: Biermann, A H; Althouse, P E; Bertoldo, N A; Blake, R G; Brigdon, S L; Brown, R A et al.
System: The UNT Digital Library
Surface Figure Metrology for CELT Primary Mirror Segments (open access)

Surface Figure Metrology for CELT Primary Mirror Segments

The University of California and California Institute of Technology are currently studying the feasibility of building a 30-m segmented ground based optical telescope called the California Extremely Large Telescope (CELT). The early ideas for this telescope were first described by Nelson and Mast and more recently refined by Nelson. In parallel, concepts for the fabrication of the primary segments were proposed by Mast, Nelson and Sommargren where high risk technologies were identified. One of these was the surface figure metrology needed for fabricating the aspheric mirror segments. This report addresses the advanced interferometry that will be needed to achieve 15nm rms accuracy for mirror segments with aspheric departures as large as 35mm peak-to-valley. For reasons of cost, size, measurement consistency and ease of operation we believe it is desirable to have a single interferometer that can be universally applied to each and every mirror segment. Such an instrument is described in this report.
Date: February 27, 2001
Creator: Sommargren, G; Phillion, D; Seppala, L & Lerner, S
System: The UNT Digital Library
NIF PEPC LRU Test Stand Safety Note Addendum (open access)

NIF PEPC LRU Test Stand Safety Note Addendum

It is necessary that the NIF PEPC LRU Test Stand be modified to accommodate a new experiment. This modification will involve boring two 1/2 inch holes in the Center Loaded Upper Beam of the stand. These holes will allow a small wire to pass through half of the length of one of the long sections of 80/20 part 3030. The holes could adversely effect the load-bearing capabilities of an important structural member of the stand so calculations must be done to assure a minimal risk of part failure.
Date: September 5, 2001
Creator: Mason, D
System: The UNT Digital Library
A Revised Magnitude and Distance Amplitude Correction (MDAC2) Procedure for Regional Seismic Discriminants: Theory and Testing at NTS (open access)

A Revised Magnitude and Distance Amplitude Correction (MDAC2) Procedure for Regional Seismic Discriminants: Theory and Testing at NTS

The Magnitude and Distance Amplitude Correction (MDAC; Taylor and Hartse, 1998; Taylor et al., 2002) procedure for correcting regional seismic amplitudes for seismic event identification has been modified to include more realistic earthquake source models and source scaling. In the MDAC2 formulation we generalize the Brune (1970) earthquake source spectrum to use a more physical apparent stress model that can represent non-constant stress-drop scaling. We also event include a parameter that allows for variable P-wave and S-wave comer frequency scaling, imposing some of the constraints of ratio correction techniques (Rodger and Walter, 2002). Very Stable moment magnitude measures (Mayeda et al., 2002) from regional coda wave envelopes that have been tied to independently derived regional seismic moments are incorporated. This eliminates two fitting parameters that were necessary in relating seismic moment to magnitude. The incorporation of Bayesian tomography to replace the assumption of a constant Q0 model is also described. These modifications allow for more flexibility in the MDAC grid-search procedure. The direct tie to regional seismic moment rather than body wave magnitude reduces effects of upper mantle bias on the corrected amplitudes. In this paper, we develop the theory and test the formulation on Nevada Test Site (NTS) data.
Date: December 21, 2001
Creator: Walter, W R & Taylor, S R
System: The UNT Digital Library
Mechanical Engineering Safety Note PEPC Spreader Bar Assembly (open access)

Mechanical Engineering Safety Note PEPC Spreader Bar Assembly

The PEPC Spreader Bar Assembly consists of a spreader bar that will be attached to the PEPC Cell Housing or the Midplane Transportation Fixture during operation. While in use in the OAB (Optics Assembly Building), the Spreader Bar Assembly will be manipulated by the NOID (New Optics Insertion Device). The other critical components of the assembly are the three angular contact bearing swivels that attach the spreader bar to the lifting mechanism and the corner clamps which are used to capture the Cell Housing.
Date: August 26, 2001
Creator: Mason, D.
System: The UNT Digital Library
Dislocation dynamics: simulation of plastic flow of bcc metals (open access)

Dislocation dynamics: simulation of plastic flow of bcc metals

This is the final report for the LDRD strategic initiative entitled ''Dislocation Dynamic: Simulation of Plastic Flow of bcc Metals'' (tracking code: 00-SI-011). This report is comprised of 6 individual sections. The first is an executive summary of the project and describes the overall project goal, which is to establish an experimentally validated 3D dislocation dynamics simulation. This first section also gives some information of LLNL's multi-scale modeling efforts associated with the plasticity of bcc metals, and the role of this LDRD project in the multiscale modeling program. The last five sections of this report are journal articles that were produced during the course of the FY-2000 efforts.
Date: February 20, 2001
Creator: Lassila, D H
System: The UNT Digital Library
Final Progress Report for the NASA Inductrack Model Rocket Launcher at the Lawrence Livermore National Laboratory (open access)

Final Progress Report for the NASA Inductrack Model Rocket Launcher at the Lawrence Livermore National Laboratory

The Inductrack magnetic levitation system, developed at the Lawrence Livermore National Laboratory, was studied for its possible use for launching rockets. Under NASA sponsorship, a small model system was constructed at the Laboratory to pursue key technical aspects of this proposed application. The Inductrack is a passive magnetic levitation system employing special arrays of high-field permanent magnets (Halbach arrays) on the levitating cradle, moving above a ''track'' consisting of a close-packed array of shorted coils with which are interleaved with special drive coils. Halbach arrays produce a strong spatially periodic magnetic field on the front surface of the arrays, while canceling the field on their back surface. Relative motion between the Halbach arrays and the track coils induces currents in those coils. These currents levitate the cradle by interacting with the horizontal component of the magnetic field. Pulsed currents in the drive coils, synchronized with the motion of the carrier, interact with the vertical component of the magnetic field to provide acceleration forces. Motional stability, including resistance to both vertical and lateral aerodynamic forces, is provided by having Halbach arrays that interact with both the upper and the lower sides of the track coils. At present, a 7.8 meter track …
Date: June 27, 2001
Creator: Tung, L S; Post, R F & Martinez-Frias, J
System: The UNT Digital Library
Three-Dimensional Analysis of Voids in AM60B Magnesium Tensile Bars Using Computed Tomography Imagery (open access)

Three-Dimensional Analysis of Voids in AM60B Magnesium Tensile Bars Using Computed Tomography Imagery

In an effort to increase automobile fuel efficiency as well as decrease the output of harmful greenhouse gases, the automotive industry has recently shown increased interest in cast light metals such as magnesium alloys in an effort to increase weight savings. Currently several magnesium alloys such as AZ91 and AM60B are being used in structural applications for automobiles. However, these magnesium alloys are not as well characterized as other commonly used structural metals such as aluminum. This dissertation presents a methodology to nondestructively quantify damage accumulation due to void behavior in three dimensions in die-cast magnesium AM60B tensile bars as a function of mechanical load. Computed tomography data was acquired after tensile bars were loaded up to and including failure, and analyzed to characterize void behavior as it relates to damage accumulation. Signal and image processing techniques were used along with a cluster labeling routine to nondestructively quantify damage parameters in three dimensions. Void analyses were performed including void volume distribution characterization, nearest neighbor distance calculations, shape parameters, and volumetric renderings of voids in the alloy. The processed CT data was used to generate input files for use in finite element simulations, both two- and three-dimensional. The void analyses revealed …
Date: May 1, 2001
Creator: Waters, A M
System: The UNT Digital Library
Carbon fiber plates production for the CMS tracker outer barrel detector (open access)

Carbon fiber plates production for the CMS tracker outer barrel detector

The production methods together with the achieved flatness and thickness of the composite support structures of the CMS tracker outer barrel (TOB) detector are presented. Possible areas of improvement in the process and in the materials used are also suggested.
Date: March 1, 2001
Creator: Lanfranco, Giobatta
System: The UNT Digital Library