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QUIET DIRECT SIMULATION OF PLASMAS (open access)

QUIET DIRECT SIMULATION OF PLASMAS

None
Date: November 1, 2001
Creator: ALBRIGHT, B. J.; DAUGHTON, W. & AL, ET
Object Type: Article
System: The UNT Digital Library
MICROHOLE TECHNOLOGY PROGRESS ON BOREHOLE INSTRUMENTATION DEVELOPMENT (open access)

MICROHOLE TECHNOLOGY PROGRESS ON BOREHOLE INSTRUMENTATION DEVELOPMENT

Microhole technology development is based on the premise that with advances in electronics and sensors, large conventional-diameter wells are no longer necessary for obtaining subsurface information. Furthermore, microholes offer an environment for improved substance measurement. The combination of deep microholes having diameters of 1-3/8 in. at their terminal depth and 7/8-in. diameter logging tools will comprise a very low cost alternative to currently available technology for deep subsurface characterization and monitoring.
Date: September 1, 2000
Creator: ALBRIGHT, J.
Object Type: Article
System: The UNT Digital Library
Acoustic Wave Equations for a Linear Viscous Fluid and An Ideal Fluid (open access)

Acoustic Wave Equations for a Linear Viscous Fluid and An Ideal Fluid

The mathematical description of acoustic wave propagation within a time- and space-varying, and moving, linear viscous fluid is formulated as a system of coupled linear equations. This system is rigorously developed from fundamental principles of continuum mechanics (conservation of mass, balance of linear and angular momentum, balance of entropy) and various constitutive relations (for stress, entropy production, and entropy conduction) by linearizing all expressions with respect to the small-amplitude acoustic wavefield variables. A significant simplification arises if the fluid medium is neither viscous nor heat conducting (i.e., an ideal fluid). In this case the mathematical system can be reduced to a set of five, coupled, first-order partial differential equations. Coefficients in the systems depend on various mechanical and thermodynamic properties of the ambient medium that supports acoustic wave propagation. These material properties cannot all be arbitrarily specified, but must satisfy another system of nonlinear expressions characterizing the dynamic behavior of the background medium. Dramatic simplifications in both systems occur if the ambient medium is simultaneously adiabatic and stationary.
Date: July 1, 2002
Creator: ALDRIDGE, DAVID F.
Object Type: Report
System: The UNT Digital Library
Elastic Wave Radiation from a Pressurized Spherical Cavity (open access)

Elastic Wave Radiation from a Pressurized Spherical Cavity

None
Date: July 1, 2002
Creator: ALDRIDGE, DAVID F.
Object Type: Report
System: The UNT Digital Library
Fast Grid Search Algorithm for Seismic Source Location (open access)

Fast Grid Search Algorithm for Seismic Source Location

The spatial and temporal origin of a seismic energy source are estimated with a first grid search technique. This approach has greater likelihood of finding the global rninirnum of the arrival time misiit function compared with conventional linearized iterative methods. Assumption of a homogeneous and isotropic seismic velocity model allows for extremely rapid computation of predicted arrival times, but probably limits application of the method to certain geologic environments and/or recording geometries. Contour plots of the arrival time misfit function in the vicinity of the global minimum are extremely useful for (i) quantizing the uncertainty of an estimated hypocenter solution and (ii) analyzing the resolving power of a given recording configuration. In particular, simultaneous inversion of both P-wave and S-wave arrival times appears to yield a superior solution in the sense of being more precisely localized in space and time. Future research with this algorithm may involve (i) investigating the utility of nonuniform residual weighting schemes, (ii) incorporating linear and/or layered velocity models into the calculation of predicted arrival times, and (iii) applying it toward rational design of microseismic monitoring networks.
Date: July 1, 2000
Creator: ALDRIDGE,DAVID F.
Object Type: Report
System: The UNT Digital Library
SPALL STUDIES IN COPPER FOILS USING THE LASER-DRIVEN MINIFLYER (open access)

SPALL STUDIES IN COPPER FOILS USING THE LASER-DRIVEN MINIFLYER

None
Date: September 1, 2000
Creator: ALEXANDER, D. J.; ROBBINS, D. L. & SHEFFIELD, S. A.
Object Type: Article
System: The UNT Digital Library
AN APPROACH TO EXTREME-SCALE SIMULATION OF NOVEL ARCHITECTURES (open access)

AN APPROACH TO EXTREME-SCALE SIMULATION OF NOVEL ARCHITECTURES

None
Date: July 1, 2001
Creator: ALEXANDER, F. J.; BERKBIGLER, K. & AL, ET
Object Type: Article
System: The UNT Digital Library
INVESTIGATION OF HALO FORMATION IN CONTINUOUS BEAMS USING WEIGHTED POLYNOMIAL EXPANSIONS AND PERTURBATIONAL ANALYSIS (open access)

INVESTIGATION OF HALO FORMATION IN CONTINUOUS BEAMS USING WEIGHTED POLYNOMIAL EXPANSIONS AND PERTURBATIONAL ANALYSIS

We consider halo formation in continuous beams oscillating at natural modes by inspecting particle trajectories. Trajectory equations containing field nonlinearities are derived from a weighted polynomial expansion. We then use perturbational techniques to further analyze particle motion.
Date: August 1, 2000
Creator: ALLEN, C.
Object Type: Article
System: The UNT Digital Library
Editing Tips for Technical Publications in the Joint Nuclear Weapons Publication System (JNWPS) (open access)

Editing Tips for Technical Publications in the Joint Nuclear Weapons Publication System (JNWPS)

These editing tips contain helpful suggestions to assist writers who are writing, editing, and publishing technical publications in the JNWPS. The suggestions clarify some of the most common writing problems and requirements of two publications used in the JNWPS: ''DOE-DTRA TP 1-1, Joint Nuclear Weapons Publications System Operating Procedures, Specifications, and Standards, and United States Government Printing Office Style Manual''. Topics include requirements for abbreviations, formats for drafts, layouts of illustrations and tables, appropriate wording for interim changes, guidance for creating a list of effective pages, how to insert and delete pages and paragraphs, referencing other technical publications, use of revision bars, requirements for safety precautions, use of hyphens, and how to place warnings, cautions, and notes. Also included are a writer's checklist, samples of draft title pages, and a section of helpful tips for the writers who use the department's desktop publishing software program, Adobe{reg_sign} FrameMaker{reg_sign}.
Date: December 1, 2002
Creator: ALLEN, TARA S.
Object Type: Report
System: The UNT Digital Library
HYBRIDIZATION AND PRESSURE EFFECTS IN UTX COMPOUNDS (open access)

HYBRIDIZATION AND PRESSURE EFFECTS IN UTX COMPOUNDS

None
Date: October 1, 2001
Creator: ALSAMDI, A.; SECHOVSKY, V. & AL, ET
Object Type: Article
System: The UNT Digital Library
Cooperative Monitoring Center Occasional Paper/16: The Potential of Technology for the Control of Small Weapons: Applications in Developing Countries (open access)

Cooperative Monitoring Center Occasional Paper/16: The Potential of Technology for the Control of Small Weapons: Applications in Developing Countries

For improving the control of small arms, technology provides many possibilities. Present and future technical means are described in several areas. With the help of sensors deployed on the ground or on board aircraft, larger areas can be monitored. Using tags, seals, and locks, important objects and installations can be safeguarded better. With modern data processing and communication systems, more information can be available, and it can be more speedily processed. Together with navigation and transport equipment, action can be taken faster and at greater range. Particular considerations are presented for cargo control at roads, seaports, and airports, for monitoring designated lines, and for the control of legal arms. By starting at a modest level, costs can be kept low, which would aid developing countries. From the menu of technologies available, systems need to be designed for the intended application and with an understanding of the local conditions. It is recommended that states start with short-term steps, such as acquiring more and better radio transceivers, vehicles, small aircraft, and personal computers. For the medium term, states should begin with experiments and field testing of technologies such as tags, sensors, and digital communication equipment.
Date: July 1, 2000
Creator: ALTMANN, JURGEN
Object Type: Report
System: The UNT Digital Library
Methodology for characterizing modeling and discretization uncertainties in computational simulation (open access)

Methodology for characterizing modeling and discretization uncertainties in computational simulation

This research effort focuses on methodology for quantifying the effects of model uncertainty and discretization error on computational modeling and simulation. The work is directed towards developing methodologies which treat model form assumptions within an overall framework for uncertainty quantification, for the purpose of developing estimates of total prediction uncertainty. The present effort consists of work in three areas: framework development for sources of uncertainty and error in the modeling and simulation process which impact model structure; model uncertainty assessment and propagation through Bayesian inference methods; and discretization error estimation within the context of non-deterministic analysis.
Date: March 1, 2000
Creator: ALVIN,KENNETH F.; OBERKAMPF,WILLIAM L.; RUTHERFORD,BRIAN M. & DIEGERT,KATHLEEN V.
Object Type: Report
System: The UNT Digital Library
Cloud to CAD (open access)

Cloud to CAD

This paper documents work performed to convert scanned range data to CAD solid model representation. The work successfully developed surface fitting algorithms for quadric surfaces (e.g. plane, cone, cylinder, and sphere), and a segmentation algorithm based entirely on surface type, rather than on a differential metric like Gaussian curvature. Extraction of all CAD-required parameters for quadric surface representation was completed. Approximate face boundaries derived from the original point cloud were constructed. Work to extrapolate surfaces, compute exact edges and solid connectivity was begun, but left incomplete due to funding reductions. The surface fitting algorithms are robust in the face of noise and degenerate surface forms.
Date: May 1, 2001
Creator: AMES,ARLO L.
Object Type: Report
System: The UNT Digital Library
A PREDICTIVE MODEL OF NUCLEON-NUCLEUS SCATTERING CROSS SECTIONS (open access)

A PREDICTIVE MODEL OF NUCLEON-NUCLEUS SCATTERING CROSS SECTIONS

None
Date: August 1, 2001
Creator: AMOS, K.; DEB, P. & KARATAGLIDIS, S.
Object Type: Article
System: The UNT Digital Library
Interim Measures to Limit the Migration of Radioactive Contaminants through the Vadose Zone at Hanford Single Shell Tank (SST) Farms (open access)

Interim Measures to Limit the Migration of Radioactive Contaminants through the Vadose Zone at Hanford Single Shell Tank (SST) Farms

None
Date: December 1, 2000
Creator: ANDERSON, F.J.
Object Type: Article
System: The UNT Digital Library
OPTIMUM ENERGY ABSORPTION OF A SHORT-PULSE LASER IN A DOPED DIELECTRIC SLAB (open access)

OPTIMUM ENERGY ABSORPTION OF A SHORT-PULSE LASER IN A DOPED DIELECTRIC SLAB

A model is used to calculate energy absorption efficiency when a short-pulse laser impinges on a dielectric slab doped with an impurity for which the electrons have a resonant line at the laser wavelength. The amount of the energy resonant absorption is due to the overlapping between laser spectrum and resonance spectrum. The energy absorption efficiency can be maximized for a certain degree of doping concentration (at a given pulselength) and also for a certain pulselength (at a given doping concentration). For a modest amount of impurity, the resonant absorption may increase the fraction of energy absorption up to tens of percent of laser energy at 100s optical cycles when the laser wavelength is tuned within 1% of the resonant line. Dimensionless parameters are constructed so that the scaling to various parameters: laser wavelength, laser pulselength, dielectric constant, slab thickness, impurity concentration, resonant linewidth, and separation between the laser wavelength and the line resonance, could easily be obtained.
Date: May 1, 2001
Creator: ANG, L.
Object Type: Article
System: The UNT Digital Library
WasteWater Treatment And Heavy Metals Removal In The A-01 Constructed Wetland 2003 Report (open access)

WasteWater Treatment And Heavy Metals Removal In The A-01 Constructed Wetland 2003 Report

The A-01 wetland treatment system (WTS) was designed to remove metals from the effluent at the A-01 NPDES outfall. The purpose of research conducted during 2003 was to evaluate (1) the ability of the A-01 wetland treatment system to remediate waste water, (2) retention of the removed contaminants in wetland sediment, and (3) the potential remobilization of these contaminants from the sediment into the water column. Surface water and sediment samples were collected and analyzed in this study.
Date: August 1, 2004
Creator: ANNA, KNOX
Object Type: Report
System: The UNT Digital Library
WHITE PAPER ON PROTON - NUCLEUS COLLISONS. (open access)

WHITE PAPER ON PROTON - NUCLEUS COLLISONS.

The role of proton-nucleus (p-A) collisions in the study of strong interactions has a long history. It has been an important testing ground for QCD. At RHIC p-A studies have been recognized since the beginning as important elements of the program. These include so-called baseline measurements in cold nuclear matter, essential (along with p-p studies) to a systematic study of QCD at high temperatures and densities in the search for the quark gluon plasma. Also accessible is a study of QCD in the small x (parton saturation) regime, complementary to physics accessible in high-energy e-p and e-A collisions. The role of p-A physics at RHIC was reviewed and brought into sharp focus at a workshop conducted in October 2000 at BNL; the agenda is shown in Appendix 1. This document summarizes the case for p-A at RHIC during the period covered by the next Nuclear Physics Long Range Plan. In subsequent sections we cover the Physics Issues, Experiment Run Plans and Schedule, Detector Upgrade Issues, and Machine Issues & Upgrades.
Date: March 1, 2001
Creator: ARONSON,S.H. & PENG,J.C.
Object Type: Report
System: The UNT Digital Library
EFFECT OF TEMPERATURE PROFILE ON REACTION VIOLENCE IN HEATED AND SELF-IGNITED PBX-9501 (open access)

EFFECT OF TEMPERATURE PROFILE ON REACTION VIOLENCE IN HEATED AND SELF-IGNITED PBX-9501

None
Date: June 1, 2001
Creator: ASAY, B.; DICKSON, P. & AL, ET
Object Type: Article
System: The UNT Digital Library
Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents (open access)

Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents

Vibrational spectra can serve as chemical fingerprints for positive identification of chemical and biological warfare molecules. The required speed and sensitivity might be achieved with surface-enhanced Raman spectroscopy (SERS) using nanotextured metal surfaces. Systematic and reproducible methods for preparing metallic surfaces that maximize sensitivity have not been previously developed. This work sought to develop methods for forming high-efficiency metallic nanostructures that can be integrated with either gas or liquid-phase chem-lab-on-a-chip separation columns to provide a highly sensitive, highly selective microanalytical system for detecting current and future chem/bio agents. In addition, improved protein microchromatographic systems have been made by the creation of acrylate-based porous polymer monoliths that can serve as protein preconcentrators to reduce the optical system sensitivity required to detect and identify a particular protein, such as a bacterial toxin.
Date: December 1, 2002
Creator: ASHBY, CAROL I.; SHEPODD, TIMOTHY J.; YELTON, WILLIAM G. & MURON, DAVID J.
Object Type: Report
System: The UNT Digital Library
Blade Manufacturing Improvement: Remote Blade Manufacturing Demonstration (open access)

Blade Manufacturing Improvement: Remote Blade Manufacturing Demonstration

The objective of this program was to investigate manufacturing improvements for wind turbine blades. The program included a series of test activities to evaluate the strength, deflection, performance, and loading characteristics of the prototype blades. The original contract was extended in order to continue development of several key blade technologies identified in the project. The objective of the remote build task was to demonstrate the concept of manufacturing wind turbine blades at a temporary manufacturing facility in a rural environment. TPI Composites successfully completed a remote manufacturing demonstration in which four blades were fabricated. The remote demonstration used a manufacturing approach which relied upon material ''kits'' that were organized in the factory and shipped to the site. Manufacturing blades at the wind plant site presents serious logistics difficulties and does not appear to be the best approach. A better method appears to be regional manufacturing facilities, which will eliminate most of the transportation cost, without incurring the logistical problems associated with fabrication directly onsite. With this approach the remote facilities would use commonly available industrial infrastructure such as enclosed workbays, overhead cranes, and paved staging areas. Additional fatigue testing of the M20 root stud design was completed with good results. …
Date: May 1, 2003
Creator: ASHWILL, THOMAS D.
Object Type: Report
System: The UNT Digital Library
Cost Study for Large Wind Turbine Blades (open access)

Cost Study for Large Wind Turbine Blades

The cost study for large wind turbine blades reviewed three blades of 30 meters, 50 meters, and 70 meters in length. Blade extreme wind design loads were estimated in accordance with IEC Class I recommendations. Structural analyses of three blade sizes were performed at representative spanwise stations assuming a stressed shell design approach and E-glass/vinylester laminate. A bill of materials was prepared for each of the three blade sizes using the laminate requirements prepared during the structural analysis effort. The labor requirements were prepared for twelve major manufacturing tasks. TPI Composites developed a conceptual design of the manufacturing facility for each of the three blade sizes, which was used for determining the cost of labor and overhead (capital equipment and facilities). Each of the three potential manufacturing facilities was sized to provide a constant annual rated power production (MW per year) of the blades it produced. The cost of the production tooling and overland transportation was also estimated. The results indicate that as blades get larger, materials become a greater proportion of total cost, while the percentage of labor cost is decreased. Transportation costs decreased as a percentage of total cost. The study also suggests that blade cost reduction efforts …
Date: May 1, 2003
Creator: ASHWILL, THOMAS D.
Object Type: Report
System: The UNT Digital Library
Innovative Design Approaches for Large Wind Turbine Blades (open access)

Innovative Design Approaches for Large Wind Turbine Blades

The primary goal of the WindPACT Blade System Design Study (BSDS) was investigation and evaluation of design and manufacturing issues for wind turbine blades in the one to ten megawatt size range. The initial project task was to assess the fundamental physical and manufacturing issues that govern and constrain large blades and entails three basic elements: (1) a parametric scaling study to assess blade structure using current technology, (2) an economic study of the cost to manufacture, transport, and install large blades, and (3) identification of promising innovative design approaches that show potential for overcoming fundamental physical and manufacturing constraints. This report discusses several innovative design approaches and their potential for blade cost reduction. During this effort we reviewed methods for optimizing the blade cross-section to improve structural and manufacturing characteristics. We also analyzed and compared a number of composite materials and evaluated their relative merits for use in large wind turbine blades in the range from 30 meters to 70 meters. The results have been summarized in dimensional and non-dimensional format to aid in interpretation. These results build upon earlier parametric and blade cost studies, which were used as a guide for the innovative design approaches explored here.
Date: March 1, 2003
Creator: ASHWILL, THOMAS D.
Object Type: Report
System: The UNT Digital Library
Parametric Study for Large Wind Turbine Blades: WindPACT Blade System Design Studies (open access)

Parametric Study for Large Wind Turbine Blades: WindPACT Blade System Design Studies

This report presents the results of a study of various wind turbine blade design parameters as a function of blade length in the range from 30 meters to 70 meters. The results have been summarized in dimensional and non-dimensional formats to aid in interpretation. The parametric review estimated peak power and annual energy capture for megawatt scale wind turbines with rotors of 62, 83, 104, 125, and 146 meters in diameter. The baseline ''thin'' distribution represents conventional airfoils used in large wind turbine blades. The ''thicker'' and ''thickest'' distributions utilize airfoils that have significantly increased thickness to improve structural performance and reduce weight. An aerodynamic scaling effort was undertaken in parallel with the structural analysis work to evaluate the effect of extreme thickness on aerodynamic characteristics. Increased airfoil section thickness appears to be a key tool in limiting blade weight and cost growth with scale. Thickened and truncated trailing edges in the inboard region provide strong, positive effects on blade structural performance. Larger blades may require higher tip speeds combined with reduced blade solidity to limit growth of design loads. A slender blade can be used to reduce extreme design loads when the rotor is parked, but requires a higher …
Date: August 1, 2002
Creator: ASHWILL, THOMAS D.
Object Type: Report
System: The UNT Digital Library