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The Factory Approach to Creating TSTT Meshes (open access)

The Factory Approach to Creating TSTT Meshes

The factory approach (a.k.a. virtual constructor) hides the details of the class implementing the TSTT from TSTT users. In version 0.5 of TSTT.sidl, the client hard codes the name of the implementing class into their code. The client is forced to choose from the small set of possible concrete classes defined in TSTT.sidl. This approach makes it impossible to support multiple implementations of the TSTT in a single process because each implementation has to implement the same class. The factory approach hides the details of mesh creation from the client. The client does not need to know the name of the implementing class, and the client can dynamically determine which interfaces are supported by the new mesh. A factory can support multiple TSTT implementation because each implementation defines its own concrete classes to implement. The factory approach does require the TSTT compliant mesh packages to implement a MeshFactory interface, and everyone needs to link against an implementation of the Registry. The Registry only has 7 methods that are fairly easy to implement, and everyone can share one implementation of the Registry.
Date: October 21, 2003
Creator: Epperly, T
System: The UNT Digital Library
Tests of the Contamination Analysis Unit, Phase 2 (open access)

Tests of the Contamination Analysis Unit, Phase 2

Results are reported for a project testing the capabilities of a mass spectrometer-based system for analyzing in-situ organic compounds on a variety of substrates. The system, which was built and operated at Lawrence Livermore National Laboratory (LLNL), is termed a Contamination Analysis Unit (CAU) and employs vacuum and thermal desorption of surface residues, followed by ionization and analysis with a Leybold Inficon Transpector mass spectrometer. The CAU was employed in this study to examine soils, cleaner residues, and substrates on Space Shuttle Reusable Solid Rocket Motor (RSRM) components. Project work was supported by ATK Thiokol Propulsion. Major project objectives include: (1) Determine residual propellant and liner components with the CAU after test coupons have been cleaned. (2) Determine if the CAU can detect solvent that has soaked into NBR insulation material, and if possible, determine the time following solvent application during which the cleaning agent is detectable. (3) Test CAU capabilities for analyzing non-flat surfaces on the inside and outside surfaces of the RSRM (12-foot diameter), and nozzle throat housing surfaces (5-foot diameter). (4) Determine if solvent extraction and gas chromatography (GC) approaches are able to enhance the surface analysis data available through use of the mass-spectrometer-based CAU. (5) Determine …
Date: January 21, 2003
Creator: Meltzer, M
System: The UNT Digital Library
NIF-0096141-OA Prop Simulations of NEL PBRS Measurements (open access)

NIF-0096141-OA Prop Simulations of NEL PBRS Measurements

Portable Back Reflection Sensor, PBRS, (NEL only) and Quad Back Reflection Sensor, QBRS, time delay reflectometer traces are among the most useful diagnostics of NIF laser status available. NEL PBRS measurements show several signals reaching the detector for each shot. The time delay between signals suggests that the largest of these is due to energy at the spatial filter pinhole planes leaking into adjacent pinholes and traveling back upstream to the PBRS. Prop simulations agree with current PBRS measurements to within 50%. This suggests that pinhole leakage is the dominant source of energy at the PBRS. However, the simulations predict that the energy leakage is proportional to beam output energy, while the PBRS measurements increase more slowly (''saturate''). Further refinement of the model or the measurement may be necessary to resolve this discrepancy.
Date: February 21, 2003
Creator: Widmayer, C. & Manes, K.
System: The UNT Digital Library
Instructions for Installation of the Whole-Building Diagnostician Software Release 2.10-162 (open access)

Instructions for Installation of the Whole-Building Diagnostician Software Release 2.10-162

The Whole Building Diagnostician (WBD) is modular diagnostic software that detects and diagnoses common problems associated with heating, ventilating, and air conditioning systems and equipment. This instruction document describes how to install the WBD and the Microsoft Data Access Object components, how to view the results in the demonstration database, and the new features of the Whole Building energy module (WBE).
Date: August 21, 2003
Creator: Carlon, Teresa A. & Bauman, Nathan N.
System: The UNT Digital Library
IR Extinction Coefficient Measurements of CH and CD GDP Shells (open access)

IR Extinction Coefficient Measurements of CH and CD GDP Shells

None
Date: March 21, 2003
Creator: Cook, R C & Nikroo, A
System: The UNT Digital Library
Freshwater Flow Charts - 1995 (open access)

Freshwater Flow Charts - 1995

This report covers the following: (1) Explanation of Charts Showing Freshwater Flow in 1995; (2) Estimated U.S. Freshwater Flow in 1995 (chart); (3) Estimated California Freshwater Flow in 1995 (chart); (4) Estimated New Mexico Freshwater Flow in 1995 (chart); and (5) Web locations and credits.
Date: November 21, 2003
Creator: Kaiper, G V
System: The UNT Digital Library
Electrical Resistivity Modeling of a Permeable Reactive Barrier for Vista Engineering Technologies: Summary (open access)

Electrical Resistivity Modeling of a Permeable Reactive Barrier for Vista Engineering Technologies: Summary

We have performed a numerical modeling study that evaluated the capacity of electrical resistance tomography (ERT) to detect flaws in a passive reactive barrier (PRB). The model barrier is based on a real barrier described in the literature Slater and Binley (2003). It consists of highly conducting, granular iron emplaced within a trench. We assumed that the barrier was filled with a mixture of iron and sand, and that vertical electrode arrays were embedded within the barrier. We have considered (a) characterization and (b) monitoring scenarios. For (a), the objective is to use tomographs of absolute resistivity to detect construction flaws and inhomogeneities in iron distribution shortly after installation. For (b), the objective is to use resistivity change tomographs to detect iron oxidation and barrier plugging as a function of time. The study considered varying PRB hole sizes and locations. For any given model, a hole was located right next to and near the center of an electrode array (maximum sensitivity and resolution expected), at the center between two electrode arrays (moderate sensitivity and resolution), or near the bottom centered between the two arrays (minimum sensitivity and resolution). We also considered various hole sizes. The smallest hole considered had a …
Date: November 21, 2003
Creator: Ramirez, A L & Daily, W D
System: The UNT Digital Library
Radar Imaging of Spheres in 3D using MUSIC (open access)

Radar Imaging of Spheres in 3D using MUSIC

We have shown that multiple spheres can be imaged by linear and planar EM arrays using only one component of polarization. The imaging approach involves calculating the SVD of the scattering response matrix, selecting a subset of singular values that represents noise, and evaluating the MUSIC functional. The noise threshold applied to the spectrum of singular values for optimal performance is typically around 1%. The resulting signal subspace includes more than one singular value per sphere. The presence of reflections from the ground improves height localization, even for a linear array parallel to the ground. However, the interference between direct and reflected energy modulates the field, creating periodic nulls that can obscure targets in typical images. These nulls are largely eliminated by normalizing the MUSIC functional with the broadside beam pattern of the array. The resulting images show excellent localization for 1 and 2 spheres. The performance for the 3 sphere configurations are complicated by shadowing effects and the greater range of the 3rd sphere in case 2. Two of the three spheres are easily located by MUSIC but the third is difficult to distinguish from other local maxima of the complex imaging functional. Improvement is seen when the linear …
Date: January 21, 2003
Creator: Chambers, D H & Berryman, J G
System: The UNT Digital Library
Mechanistic Constitutive Models for Rubber Elasticity and Viscoelasticity (open access)

Mechanistic Constitutive Models for Rubber Elasticity and Viscoelasticity

Physically based models which describe the finite strain behavior of vulcanized rubber are developed. Constitutive laws for elasticity and viscoelasticity are derived by integrating over orientation space the forces due to each individual polymer chain. A novel scheme is presented which effectively approximates these integrals in terms of strain and strain invariants. In addition, the details involving the implementation of such models into a quasi-static large strain finite element formulation are provided. In order to account for the finite extensibility of a molecular chain, Langevin statistics is used to model the chain response. The classical statistical model of rubber assumes that polymer chains interact only at the chemical crosslinks. It is shown that such model when fitted for uniaxial tension data cannot fit compression or equibiaxial data. A model which incorporates the entanglement interactions of surrounding chains, in addition to the finite extensibility of the chains, is shown to give better predictions than the classical model. The technique used for approximating the orientation space integral was applied to both the classical and entanglement models. A viscoelasticity model based on the force equilibration process as described by Doi and Edwards is developed. An assumed form for the transient force in the …
Date: January 21, 2003
Creator: Puso, M
System: The UNT Digital Library
Building CHAOS: An Operating System for Livermore Linux Clusters (open access)

Building CHAOS: An Operating System for Livermore Linux Clusters

The Livermore Computing (LC) Linux Integration and Development Project (the Linux Project) produces and supports the Clustered High Availability Operating System (CHAOS), a cluster operating environment based on Red Hat Linux. Each CHAOS release begins with a set of requirements and ends with a formally tested, packaged, and documented release suitable for use on LC's production Linux clusters. One characteristic of CHAOS is that component software packages come from different sources under varying degrees of project control. Some are developed by the Linux Project, some are developed by other LC projects, some are external open source projects, and some are commercial software packages. A challenge to the Linux Project is to adhere to release schedules and testing disciplines in a diverse, highly decentralized development environment. Communication channels are maintained for externally developed packages in order to obtain support, influence development decisions, and coordinate/understand release schedules. The Linux Project embraces open source by releasing locally developed packages under open source license, by collaborating with open source projects where mutually beneficial, and by preferring open source over proprietary software. Project members generally use open source development tools. The Linux Project requires system administrators and developers to work together to resolve problems that …
Date: February 21, 2003
Creator: Garlick, Jim E. & Dunlap, Chris M.
System: The UNT Digital Library
Overview of Stellarator Divertor Studies: Final Report of LDRD Project 01-ERD-069 (open access)

Overview of Stellarator Divertor Studies: Final Report of LDRD Project 01-ERD-069

A summary is given of the work carried out under the LDRD project 01-ERD-069 entitled Stellarator Divertor Studies. This project has contributed to the development of a three-dimensional edge-plasma modeling and divertor diagnostic design capabilities at LLNL. Results are demonstrated by sample calculations and diagnostic possibilities for the edge plasma of the proposed U.S. National Compact Stellarator Experiment device. Details of the work are contained in accompanying LLNL reports that have been accepted for publication.
Date: January 21, 2003
Creator: Fenstermacher, M. E.; Rognlien, T. D.; Koniges, A.; Unmansky, M. & Hill, D. N.
System: The UNT Digital Library
An Improved Coal Liquefaction Process (open access)

An Improved Coal Liquefaction Process

Short Residence Time & Low and High Shear Rate Coal and Oil Feedstock Test
Date: April 21, 2003
Creator: Lee, Theo Lap-Keung
System: The UNT Digital Library
Microwave Treatment as a Pesticide Alternative for Stored-Products (open access)

Microwave Treatment as a Pesticide Alternative for Stored-Products

None
Date: May 21, 2003
Creator: Bigelow, T.; Forrester, S.; Halverson, S.; Halverson, B. & Phillips, T.
System: The UNT Digital Library
Microwave Treatment as a Pesticide Alternative for Stored-Products (open access)

Microwave Treatment as a Pesticide Alternative for Stored-Products

This CRADA was a continuation of earlier work with Micro-Grain, Inc. to develop power, high frequency microwave treatment process to treat insect infested grain. ORNLs role was as a subcontractor to Micro-Grain's Phase II SBIR project funded by the US Department of Agriculture. The primary objective was to develop a commercial scale prototype unit capable of treating infested grain at flow rates approaching 1 kg/sec, which is required to be viable in the grain handling industry. A flow rate of {approx} 0.12 Kg/second was demonstrated at 20 kW microwave power level with 100% kill rate. The system is capable of 200 kW however waveguide arcing due to grain dust in the waveguide limited the power to 20 kW during the tests. Development tasks performed during the project included modification of an existing high-power microwave exposure facility to uniformly process large grain samples at high flow rates and improved instrumentation to detect grain flow and uniformity. Microwave processing tasks include a series of controlled exposure tests using infested grain samples provided and analyzed by the University of Oklahoma. Grain samples were infested with red flour beetles which proved the most difficult to kill in earlier tests. Most of the samples processed …
Date: May 21, 2003
Creator: Bigelow, T.S.; Forrester, S.C.; Halverson, S.; Halverson, B. & Phillips, T.
System: The UNT Digital Library
Microturbine Power Conversion Technology Review (open access)

Microturbine Power Conversion Technology Review

In this study, the Oak Ridge National Laboratory (ORNL) is performing a technology review to assess the market for commercially available power electronic converters that can be used to connect microturbines to either the electric grid or local loads. The intent of the review is to facilitate an assessment of the present status of marketed power conversion technology to determine how versatile the designs are for potentially providing different services to the grid based on changes in market direction, new industry standards, and the critical needs of the local service provider. The project includes data gathering efforts and documentation of the state-of-the-art design approaches that are being used by microturbine manufacturers in their power conversion electronics development and refinement. This project task entails a review of power converters used in microturbines sized between 20 kW and 1 MW. The power converters permit microturbine generators, with their non-synchronous, high frequency output, to interface with the grid or local loads. The power converters produce 50- to 60-Hz power that can be used for local loads or, using interface electronics, synchronized for connection to the local feeder and/or microgrid. The power electronics enable operation in a stand-alone mode as a voltage source or …
Date: July 21, 2003
Creator: Staunton, R.H.
System: The UNT Digital Library
Information Management Infrastructure for the Systematic Annotation of Vertebrate Genomes (open access)

Information Management Infrastructure for the Systematic Annotation of Vertebrate Genomes

The primary accomplishment of the project has been the development of a functional genomics database system, GUS (Genomics Unified Schema). The system provides a relational schema, application framework, and web interface for multiple projects and includes information on sequences, gene expression, gene regulation, ontologies, and data provenance. The system has been made portable and has been set up at other institutions. A web site is available describing the system and providing links for downloading code at http://www.gusdb.org.
Date: March 21, 2003
Creator: Stoeckert, Christian J.
System: The UNT Digital Library
Boiler Materials for Ultrasupercritical Coal Power Plants (open access)

Boiler Materials for Ultrasupercritical Coal Power Plants

The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). The project goal initially was to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi), although this goal for the main steam temperature had to be revised down to 732 C (1350 F), based on a preliminary assessment of material capabilities. The project is intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under …
Date: April 21, 2003
Creator: Viswanathan, R.; Sarver, J.; Borden, M.; Coleman, K.; Blough, J.; Goodstine, S. et al.
System: The UNT Digital Library
Thermal conductivity Measurements of Kaolite (open access)

Thermal conductivity Measurements of Kaolite

Testing was performed to determine the thermal conductivity of Kaolite 1600, which primarily consists of Portland cement and vermiculite. The material was made by Thermal Ceramics for refractory applications. Its combination of light weight, low density, low cost, and noncombustibility made it an attractive alternative to the materials currently used in ES-2 container for radioactive materials. Mechanical properties and energy absorption tests of the Kaolite have been conducted at the Y-12 complex. Heat transfer is also an important factor for the application of the material. The Kaolite samples are porous and trap moisture after extended storage. Thermal conductivity changes as a function of moisture content below 100 C. Thermal conductivity of the Kaolite at high temperatures (up to 700 C) are not available in the literature. There are no standard thermal conductivity values for Kaolite because each sample is somewhat different. Therefore, it is necessary to measure thermal conductivity of each type of Kaolite. Thermal conductivity measurements will help the modeling and calculation of temperatures of the ES-2 containers. This report focuses on the thermal conductivity testing effort at ORNL.
Date: February 21, 2003
Creator: Wang, H
System: The UNT Digital Library
DEMONSTRATiON OF A SUBSURFACE CONTAINMENT SYSTEM FOR INSTALLATION AT DOE WASTE SITES (open access)

DEMONSTRATiON OF A SUBSURFACE CONTAINMENT SYSTEM FOR INSTALLATION AT DOE WASTE SITES

Between 1952 and 1970, DOE buried mixed waste in pits and trenches that now have special cleanup needs. The disposal practices used decades ago left these landfills and other trenches, pits, and disposal sites filled with three million cubic meters of buried waste. This waste is becoming harmful to human safety and health. Today's cleanup and waste removal is time-consuming and expensive with some sites scheduled to complete cleanup by 2006 or later. An interim solution to the DOE buried waste problem is to encapsulate and hydraulically isolate the waste with a geomembrane barrier and monitor the performance of the barrier over its 50-yr lifetime. The installed containment barriers would isolate the buried waste and protect groundwater from pollutants until final remediations are completed. The DOE has awarded a contract to RAHCO International, Inc.; of Spokane, Washington; to design, develop, and test a novel subsurface barrier installation system, referred to as a Subsurface Containment System (SCS). The installed containment barrier consists of commercially available geomembrane materials that isolates the underground waste, similar to the way a swimming pools hold water, without disrupting hazardous material that was buried decades ago. The barrier protects soil and groundwater from contamination and effectively meets …
Date: May 21, 2003
Creator: Crocker, Thomas J. & Carpenter, Verna M.
System: The UNT Digital Library
Nondestructive Characterization of Aged Components (open access)

Nondestructive Characterization of Aged Components

It is known that high energy radiation can have numerous effects on materials. In metals and alloys, the effects include, but may not be limited to, mechanical property changes, physical property changes, compositional changes, phase changes, and dimensional changes. Metals and alloys which undergo high energy self-irradiation are also susceptible to these changes. One of the greatest concerns with irradiation of materials is the phenomenon of void swelling which has been observed in a wide variety of metals and alloys. Irradiation causes the formation of a high concentration point defects and microclusters of vacancies and interstitials. With the assistance of an inert atom such as helium, the vacancy-type defects can coalesce to form a stable bubble. This bubble will continue to grow through the net absorption of more vacancy-type defects and helium atoms, and upon reaching a certain critical size, the bubble will begin to grow at an accelerated rate without the assistance of inert atom absorption. The bubble is then said to be an unstably growing void. Depending on the alloy system and environment, swelling values can reach in excess of 50% !V/Vo where Vo is the initial volume of the material. Along with dimensional changes resulting from the …
Date: October 21, 2003
Creator: Panetta, Paul D.; Toloczko, Mychailo B.; Garner, Francis A. & Balachov, Iouri I.
System: The UNT Digital Library
China's Space Program: An Overview (open access)

China's Space Program: An Overview

This report discusses the nature and scope of the Chinese space program. The People's Republic of China launched its first astronaut, or "taikonaut," Lt. Col. Yang Liwei, on October 15, 2003 Beijing time (October 16 Eastern Daylight Time). China thus became only the third country, after Russia and the United States, able to launch humans into orbit. Lt. Col. Yang landed on October 16 Beijing time (October 15 EDT) after making 14 orbits (21 hours and 23 minutes).
Date: October 21, 2003
Creator: Smith, Marcia S.
System: The UNT Digital Library
Military Retirement: Major Legislative Issues (open access)

Military Retirement: Major Legislative Issues

This report discusses various proposed changes to the military retirement system, which includes benefits for retirement after an active or reserve military career, disability retirement, and survivor benefits for eligible survivors of deceased retirees. Major issues include whether some or all military retirees should be allowed to receive both military retired pay and any VA disability compensation to which they are otherwise entitled -- referred to as "concurrent receipt" -- whether some military personnel should be entitled to military retired pay with less than 20 years of service, and whether many more personnel should serve well past the 20-year point before retiring.
Date: October 21, 2003
Creator: Goldich, Robert L.
System: The UNT Digital Library
Sponsorship and Cosponsorship of House Bills (open access)

Sponsorship and Cosponsorship of House Bills

This report discusses the sponsorship and co-sponsorship of House bills. A Representative who introduces a bill or other measure in the House is called its sponsor. Under House Rule XII, clause 7, several Members together may submit a bill, but the first-named Representative is considered the chief or primary sponsor; the others are considered cosponsors.
Date: April 21, 2003
Creator: Sachs, Richard C.
System: The UNT Digital Library
The Right to Die: Constitutional and Statutory Analysis (open access)

The Right to Die: Constitutional and Statutory Analysis

None
Date: December 21, 2003
Creator: unknown
System: The UNT Digital Library