Acoustic and Seismic Modalities for Unattended Ground Sensors (open access)

Acoustic and Seismic Modalities for Unattended Ground Sensors

In this paper, we have presented the relative advantages and complementary aspects of acoustic and seismic ground sensors. A detailed description of both acoustic and seismic ground sensing methods has been provided. Acoustic and seismic phenomenology including source mechanisms, propagation paths, attenuation, and sensing have been discussed in detail. The effects of seismo-acoustic and acousto-seismic interactions as well as recommendations for minimizing seismic/acoustic cross talk have been highlighted. We have shown representative acoustic and seismic ground sensor data to illustrate the advantages and complementary aspects of the two modalities. The data illustrate that seismic transducers often respond to acoustic excitation through acousto-seismic coupling. Based on these results, we discussed the implications of this phenomenology on the detection, identification, and localization objectives of unattended ground sensors. We have concluded with a methodology for selecting the preferred modality (acoustic and/or seismic) for a particular application.
Date: March 31, 1999
Creator: Elbring, G.J.; Ladd, M.D.; McDonald, T.S. & Sleefe, G.E.
Object Type: Article
System: The UNT Digital Library
Advanced Silicon Space Solar Cells Using Nanotechnology (open access)

Advanced Silicon Space Solar Cells Using Nanotechnology

Application of nanotechnology and advanced optical structures offer new possibilities for improved radiation tolerance in silicon solar cells. We describe the application of subwavelength diffractive structures to enhance optical absorption near the surface, and thereby improve the radiation tolerance.
Date: March 31, 1999
Creator: Gee, J. M.; Ruby, D. S. & Zaidi, S. H.
Object Type: Article
System: The UNT Digital Library
Advanced Thermal Barrier Coating System Development (open access)

Advanced Thermal Barrier Coating System Development

The objectives of the program are to provide an improved Thermal Barrier Coating (TBC) system with increased temperature capability and improved reliability relative to current state of the art TBC systems. The development of such a coating system is essential to the ATS engine meeting its objectives. The base program consists of three phases: Phase I: Program Planning - Complete; Phase II: Development; and Phase III: Selected Specimen - Bench Test Work is being performed in Phase II and III of the program.
Date: March 31, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Analytical studies of top-up safety at the Advanced Photon Source. (open access)

Analytical studies of top-up safety at the Advanced Photon Source.

The Advanced Photon source (APS) is a 7 GeV, third-generation synchrotron radiation source. To provide more stable beam for users, they are pursuing a new operating mode called top-up. In this mode, the beam current is not allowed to decay as it normally would, but instead is maintained at a high level through frequent injection. A safety question with top-up mode is, during injection with photon shutters open, can injected beam ever exit a photon beamline? This might happen, for example, due to a full or partial short of a dipole coil. The authors discuss a number of analytical calculations that can be used to quickly assess top-up safety for a general ring. They also apply these results to the specific case of the APS. A companion paper in this conference discusses detailed tracking procedures for assessing safety.
Date: March 31, 1999
Creator: Emery, L.
Object Type: Article
System: The UNT Digital Library
Application of statistical methods for analyzing the relationship between casting distortion, mold filling, and interfacial heat transfer in sand molds (open access)

Application of statistical methods for analyzing the relationship between casting distortion, mold filling, and interfacial heat transfer in sand molds

This report presents a statistical method of evaluating geometric tolerances of casting products using point cloud data generated by coordinate measuring machine (CMM) process. The focus of this report is to present a statistical-based approach to evaluate the differences in dimensional and form variations or tolerances of casting products as affected by casting gating system, molding material, casting thickness, and casting orientation at the mold-metal interface. Form parameters such as flatness, parallelism, and other geometric profiles such as angularity, casting length, and height of casting products were obtained and analyzed from CMM point cloud data. In order to relate the dimensional and form errors to the factors under consideration such as flatness and parallelism, a factorial analysis of variance and statistical test means methods were performed to identify the factors that contributed to the casting distortion at the mold-metal interface.
Date: March 31, 1999
Creator: Owusu, Y. A.
Object Type: Report
System: The UNT Digital Library
Automated Sample collection and Analysis unit (open access)

Automated Sample collection and Analysis unit

Autoramp is an atmospheric radionuclide collection and analysis unit designed for unattended operation. A large volume of air passes through one of 31 filter cartridges which is then moved from a sampling chamber and past a bar code reader, to a shielded enclosure. The collected dust-borne radionuclides are counted with a high resolution germanium gamma-ray detector. An analysis is made and the results are transmitted to a central station that can also remotely control the unit.
Date: March 31, 1999
Creator: Latner, Norman; Sanderson, Colin G. & Negro, Vincent C.
Object Type: Patent
System: The UNT Digital Library
Automation and integration of multiplexed on-line sample preparation with capillary electrophoresis for DNA sequencing (open access)

Automation and integration of multiplexed on-line sample preparation with capillary electrophoresis for DNA sequencing

The purpose of this research is to develop a multiplexed sample processing system in conjunction with multiplexed capillary electrophoresis for high-throughput DNA sequencing. The concept from DNA template to called bases was first demonstrated with a manually operated single capillary system. Later, an automated microfluidic system with 8 channels based on the same principle was successfully constructed. The instrument automatically processes 8 templates through reaction, purification, denaturation, pre-concentration, injection, separation and detection in a parallel fashion. A multiplexed freeze/thaw switching principle and a distribution network were implemented to manage flow direction and sample transportation. Dye-labeled terminator cycle-sequencing reactions are performed in an 8-capillary array in a hot air thermal cycler. Subsequently, the sequencing ladders are directly loaded into a corresponding size-exclusion chromatographic column operated at {approximately} 60 C for purification. On-line denaturation and stacking injection for capillary electrophoresis is simultaneously accomplished at a cross assembly set at {approximately} 70 C. Not only the separation capillary array but also the reaction capillary array and purification columns can be regenerated after every run. DNA sequencing data from this system allow base calling up to 460 bases with accuracy of 98%.
Date: March 31, 1999
Creator: Tan, H.
Object Type: Report
System: The UNT Digital Library
A Cercla-Based Decision Model to Support Remedy Selection for an Uncertain Volume of Contaminants at a DOE Facility (open access)

A Cercla-Based Decision Model to Support Remedy Selection for an Uncertain Volume of Contaminants at a DOE Facility

The Paducah Gaseous Diffusion Plant (PGDP) operated by the Department of Energy is challenged with selecting the appropriate remediation technology to cleanup contaminants at Waste Area Group (WAG) 6. This research utilizes value-focused thinking and multiattribute preference theory concepts to produce a decision analysis model designed to aid the decision makers in their selection process. The model is based on CERCLA's five primary balancing criteria, tailored specifically to WAG 6 and the contaminants of concern, utilizes expert opinion and the best available engineering, cost, and performance data, and accounts for uncertainty in contaminant volume. The model ranks 23 remediation technologies (trains) in their ability to achieve the CERCLA criteria at various contaminant volumes. A sensitivity analysis is performed to examine the effects of changes in expert opinion and uncertainty in volume. Further analysis reveals how volume uncertainty is expected to affect technology cost, time and ability to meet the CERCLA criteria. The model provides the decision makers with a CERCLA-based decision analysis methodology that is objective, traceable, and robust to support the WAG 6 Feasibility Study. In addition, the model can be adjusted to address other DOE contaminated sites.
Date: March 31, 1999
Creator: Kerschus, Christine E.
Object Type: Report
System: The UNT Digital Library
Coal and char studies by advanced EMR techniques (open access)

Coal and char studies by advanced EMR techniques

Advanced magnetic resonance (EMR) methods are used to examine properties of coals, chars, and molecular species related to constituents of coal. During this grant period, further progress was made on proton NMR and low-frequency dynamic nuclear polarization (DNP) to examine the interaction between fluids such as water and the surface of suspended char particles. Effects of char particle size and type on water nuclear spin relaxation, T2, were measured and modeled.
Date: March 31, 1999
Creator: Belford, R. L.; Clarkson, R. B. & Odintsov, B. M.
Object Type: Report
System: The UNT Digital Library
Comparison of F(2)-Based Gases for High-Rate Dry Etching of Si (open access)

Comparison of F(2)-Based Gases for High-Rate Dry Etching of Si

Four different F{sub 2}-based gases (SF{sub 6}, NF{sub 3}, PF{sub 5}, and BF{sub 3}) were examined for high rate Inductively Coupled Plasma etching of Si. Etch rates up to {approximately}8 {micro}m/min were achieved with pure SF{sub 6} discharges at high source power (1500W) and pressure (35mTorr). A direct comparison of the four feedstock gases under the same plasma conditions showed the Si etch rate to increase in the order BF{sub 3} < NF{sub 3} < PF{sub 5} < SF{sub 6}. This is in good correlation with the average bond energies of the gases, except for NF{sub 3}, which is the least strongly bound. Optical emission spectroscopy showed that the ICP source efficiently dissociated NF{sub 3}, but the etched Si surface morphologies were significantly worse with this gas than with the other 3 gases.
Date: March 31, 1999
Creator: Donahue, J.; Hahn, Y.B.; Hays, D.C.; Johnson, D.; Jung, K.B.; Lambers, E.S. et al.
Object Type: Article
System: The UNT Digital Library
A comprehensive study of fracture patterns and densities in the Geysers geothermal reservoir using microearthquake shear-wave splitting tomography. Quarterly report for Sep-Dec 1998 (open access)

A comprehensive study of fracture patterns and densities in the Geysers geothermal reservoir using microearthquake shear-wave splitting tomography. Quarterly report for Sep-Dec 1998

We start organizing the computer programs needed for crack density inversion into an easy to follow scripts. These programs were collection of bits and pieces from many sources and we want to organize those separate programs into coherent product. We also gave a presentation (enclosed) in the Twenty-Fourth Workshop on Geothermal Reservoir Engineering in Stanford University on our Geyser and Mammoth results.
Date: March 31, 1999
Creator: Malin, Peter E. & Shalev, Eylon
Object Type: Report
System: The UNT Digital Library
DEVELOPMENT OF A CALCIUM-BASED SORBENT FOR HOT GAS CLEANUP (open access)

DEVELOPMENT OF A CALCIUM-BASED SORBENT FOR HOT GAS CLEANUP

The preparation and testing of potential sorbents for removing H{sub 2}S and COS from hot coal gas continued. Two preparation methods received the most consideration. Both methods involve pelletizing powders in a revolving drum under moist conditions followed either by heat treatment or steam curing to harden the pellets, depending on the particle bonding mechanism. One method was used to pelletize mixtures of calcium carbonate and either alumina or a calcium aluminate cement in a single step. Another method was used to pelletize powdered limestone in an initial step followed by the application of a coating consisting of both limestone and a hydraulic cement in a second step. By employing this method, an especially promising material was produced consisting of a limestone core surrounded by a shell consisting initially of 80 wt.% limestone and 20% wt.% calcium aluminate cement. The best material exhibited both an acceptable crushing strength and adsorption capacity for H{sub 2}S.
Date: March 31, 1999
Creator: Wheelock, T. D.; Doraiswamy, L. K. & Constant, K.
Object Type: Report
System: The UNT Digital Library
DEVELOPMENT OF AN ON-LINE COAL WASHABILITY ANALYZER (open access)

DEVELOPMENT OF AN ON-LINE COAL WASHABILITY ANALYZER

Washability analysis is the basis for nearly all coal preparation plant separations. Unfortunately, there are no on-line techniques for determining this most fundamental of all coal cleaning information. In light of recent successes at the University of Utah, it now appears possible to determine coal washability on-line through the use of x-ray computed tomography (CT) analysis. The successful development of such a device is critical to the establishment of process control and automated coal blending systems. In this regard, Virginia Tech, Terra Tek Inc., and several eastern coal companies have joined with the University of Utah and agreed to undertake the development of a x-ray CT-based on-line coal washability analyzer with financial assistance from DOE. The three-year project will cost $594,571, of which 33% ($194,575) will be cost-shared by the participants. The project involves development of appropriate software and extensive testing/evaluation of well-characterized coal samples from operating coal preparation plants. Each project participant brings special expertise to the project which is expected to create a new dimension in coal cleaning technology. Finally, it should be noted that the analyzer may prove to be a universal analyzer capable of providing not only washability analysis, but also particle size distribution analysis, ash …
Date: March 31, 1999
Creator: Lin, C.L.; Luttrell, G.H.; Adel, G.T. & Miller, Jan D.
Object Type: Report
System: The UNT Digital Library
DNA Uptake by Transformable Bacteria (open access)

DNA Uptake by Transformable Bacteria

The various processes of DNA uptake by cells can be categorized as: viral DNA entry, conjugation, or transformation. Within each category, a variety of mechanisms have been found. However, considerable similarities occur among the different mechanisms of conjugation and, especially, transformation. All of these natural mechanisms of DNA transfer are quite elaborate and involve multiple protein components, as the case may be, of the virus, the donor cell, and the recipient cell. The mechanisms of viral infection and conjugation will be discussed mainly with respect to their relevance to transformation.
Date: March 31, 1999
Creator: Lacks, Sanford A.
Object Type: Article
System: The UNT Digital Library
Energy Technology Division research summary - 1999. (open access)

Energy Technology Division research summary - 1999.

The Energy Technology Division provides materials and engineering technology support to a wide range of programs important to the US Department of Energy. As shown on the preceding page, the Division is organized into ten sections, five with concentrations in the materials area and five in engineering technology. Materials expertise includes fabrication, mechanical properties, corrosion, friction and lubrication, and irradiation effects. Our major engineering strengths are in heat and mass flow, sensors and instrumentation, nondestructive testing, transportation, and electromechanics and superconductivity applications. The Division Safety Coordinator, Environmental Compliance Officers, Quality Assurance Representative, Financial Administrator, and Communication Coordinator report directly to the Division Director. The Division Director is personally responsible for cultural diversity and is a member of the Laboratory-wide Cultural Diversity Advisory Committee. The Division's capabilities are generally applied to issues associated with energy production, transportation, utilization, or conservation, or with environmental issues linked to energy. As shown in the organization chart on the next page, the Division reports administratively to the Associate Laboratory Director (ALD) for Energy and Environmental Science and Technology (EEST) through the General Manager for Environmental and Industrial Technologies. While most of our programs are under the purview of the EEST ALD, we also have had …
Date: March 31, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Estimating the Maximum Splat Diameter of a Solidifying Droplet (open access)

Estimating the Maximum Splat Diameter of a Solidifying Droplet

We present a simple analytical model for the estimation of the maximum splat diameter of an impacting droplet on a subcooled target. This work is an extension of the isothermal model of Pasandideh-Fard et al. (1996). The model uses an energy conservation argument, applied between the initial and final drop configurations, to approximately capture the dynamics of spreading. The effects of viscous dissipation, surface tension, and contact angle are taken into account. Tests against limited experimental data at high Reynolds and Weber numbers indicate that an accuracy of the order of 5% is achieved with no adjustable parameters required. Agreement with experimental data in the limit We {yields} {infinity} is also very good. We additionally propose a simple model for the estimation of the thickness of the freezing layer developed at the droplet-substrate contact during droplet spreading. This model accounts for the effect of thermal contact resistance and its predictions compare favorably with experimental data.
Date: March 31, 1999
Creator: Hadjiconstantinou, N.G.
Object Type: Article
System: The UNT Digital Library
Final Report: Absorption Chiller Corrosion Protection, September 1, 1999 - March 31, 1999 (open access)

Final Report: Absorption Chiller Corrosion Protection, September 1, 1999 - March 31, 1999

None
Date: March 31, 1999
Creator: Chandler, Travis
Object Type: Report
System: The UNT Digital Library
Final Report: Measuring the Effects of a Unique Law Limiting Employee Medical Examinations to Job-Related Matters, April 1, 1997 - March 31, 1999 (open access)

Final Report: Measuring the Effects of a Unique Law Limiting Employee Medical Examinations to Job-Related Matters, April 1, 1997 - March 31, 1999

None
Date: March 31, 1999
Creator: Rothstein, Mark A.; Gelb, Betsy D. & Craig, Steven G.
Object Type: Report
System: The UNT Digital Library
Final Report: Task Force on requirements for HPC software: Guidelines for specifying HPC software, June 1, 1997 - August 31, 1999 (open access)

Final Report: Task Force on requirements for HPC software: Guidelines for specifying HPC software, June 1, 1997 - August 31, 1999

This document describes the results of a task force convened to determine what types of system software and tools were sufficiently important to warrant implementation across multiple vendors and machine types. The group included representatives from a wide range of user sites, as well as from the software development groups at vendor sites. Together, they established key software requirements, identified priorities for different types of user organizations, and formulated the requirements into language suitable for direct inclusion in procurements and requests-for-bids. The report is structured into four sections. The first discusses the formation and objectives of the task force and the processes used to arrive at consensus. Part 2 outlines the group's assumptions about how software will be specified on RFPs for parallel and clustered computers. In the next section, a tabular summary describes the requirements and the priority rank that was assigned to each. Part 4 presents the wording that is recommended for specifying each software element. Examples of how the requirements might be applied for various RFP scenarios, are in the appendices, which also provide vendor estimations of the level-of-effort required to develop and supply each requirement. The task force was sponsored by the Parallel Tools Consortium and …
Date: March 31, 1999
Creator: Pancake, Cherri M.
Object Type: Report
System: The UNT Digital Library
Fluidtight Seal for a Container (open access)

Fluidtight Seal for a Container

A fluidtight seal for a container is formed by abutting a metal ring with a step machined in a convexo-concave container closure device and inserting this assembly into an open end of the container. Under compressive force, the closure device deforms causing the metal ring to pivot about the step on the closure device and interact with symmetrically tapered inner walls of the container to form a fluidtight seal between the container and the closure device. The compressive force is then withdrawn without affecting the fluidtight characteristic of the seal. A destructive force against the container closure device is necessary to destroy the fluidtight seal.
Date: March 31, 1999
Creator: Morrison, Edward F.
Object Type: Patent
System: The UNT Digital Library
Forward-in-Time Differencing for Fluids: Nonhydrostatic Modeling of Rotating Stratified Flow on a Mountainous Sphere (open access)

Forward-in-Time Differencing for Fluids: Nonhydrostatic Modeling of Rotating Stratified Flow on a Mountainous Sphere

Traditionally, numerical models for simulating planetary scale weather and climate employ the hydrostatic primitive equations-an abbreviated form of Navier-Stokes equations that neglect vertical accelerations and use simplified inertial forces. 1 Although there is no evidence so far that including nonhydrostatic effects in global models has any physical significance for large scale solutions, there is an apparent trend in the community toward restoring Navier-Stokes equations (or at least their less constrained forms) in global models of atmospheres and oceans. The primary motivation for this is that the state-of-the-art computers already admit resolutions where local nonhydrostatic effects become noticeable. Other advantages include: the convenience of local mesh refinement; better overall accuracy; insubstantial computational overhead relative to hydrostatic models; universality and therefore convenience of maintaining a single large code; as well as conceptual simplicity and mathematical elegancy--features important for education. The few existing nonhydrostatic global models differ in analytic formulation and numerical design, reflecting their different purposes and origins. Much of our present research improves the design of a high-performance numerical model for simulating the flows of moist (and precipitating), rotating, stratified fluids past a specified time-dependent irregular lower boundary. This model is representative of a class of nonhydrostatic atmospheric codes employing the …
Date: March 31, 1999
Creator: Smolarkiewicz, P.K.; Grubisic, V. & Margolin, L.G.
Object Type: Article
System: The UNT Digital Library
In-Situ Air Permeability Measurements Using the Cone Permeameter at the 200 East Area of the Hanford Site (open access)

In-Situ Air Permeability Measurements Using the Cone Permeameter at the 200 East Area of the Hanford Site

This report documents the field demonstration of the Cone Permeameter{trademark} (CPer) conducted at the Immobilization Low-Activity Waste (ILAW) site in the 200 East area of the Department of Energy's (DOE) Hanford facility. The demonstration was conducted using the Hanford Site Cone Penetration Platform (CPP) shown in Figure 1.1. The purpose of the technology demonstration was to (1) gather baseline data and evaluate the CPer's ability to measure air permeability in arid sands, silts and gravels; and (2) to determine the system's ability to replicate permeability profiles with multiple pushes in close proximity. The demonstration was jointly conducted by Applied Research Associates, Inc. (ARA) and Science and Engineering Associates (SEA). This report satisfies the requirements of ARA's contract No.2075 to Lockheed Martin Hanford Company. The report is organized into six major sections. This first section presents an introduction and outline to the report. Section 2 contains a discussion of the technologies used for the demonstration. Section 3 contains a brief description of the site where the demonstration was conducted. Section 4 describes the testing methodology and chronology. Section 5 presents the results obtained during the field test program. Comparisons between these results and existing site data are developed and discussed in …
Date: March 31, 1999
Creator: TROYER, G.L.
Object Type: Report
System: The UNT Digital Library
Induced energy-saving innovation in industrial durable goods. Final report (open access)

Induced energy-saving innovation in industrial durable goods. Final report

None
Date: March 31, 1999
Creator: Newell, Richard G.
Object Type: Report
System: The UNT Digital Library
Inertial Confinement Fusion Quarterly Report January-March 1999, Volume 9, Number 2 (open access)

Inertial Confinement Fusion Quarterly Report January-March 1999, Volume 9, Number 2

This quarterly report covers the following topics: (1) Properties of and Manufacturing Methods for NIF Laser Glasses (J. H. Campbell)--The NIF amplifiers require 3380 Nd-doped laser glass slabs; continuous glass melting methods will be used for the first time to manufacture these slabs. The properties of the laser glasses are summarized and the novel continuous melting method is described. (2) Diffractive Optics for the NIF (J. A. Britten)--We have fabricated demonstration diffractive optics according to the NIF baseline design at full scale, via wet-chemical etching of patterns into fused silica. We have examined the effects of dip-coated sol-gel antireflection coatings on the performance of these optics, and have concluded that diffractive optics should remain uncoated to minimize laser-induced damage to downstream optics and to maximize environmental stability. We have also demonstrated the feasibility of combining all diffractive structures required by NIF, which vary over orders of magnitude in lateral and vertical scales, onto a single surface. (3) Producing KDP and DKDP Crystals for the NIF Laser (A. K. Burnham)--Rapid-growth KDP has overcome most of the hurdles for production of boules for NIF switch crystals and doublers, but some improvements in process reliability at the tripler's 3{omega} damage threshold are needed. …
Date: March 31, 1999
Creator: Atherton, J.
Object Type: Report
System: The UNT Digital Library