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1999

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A Numerical Simulation Of A Carbon Black Suspension Cell Via A Time-Reversed, Double Layer Compute Algorithm, Gregg T. Anderson Dec 1999

A Numerical Simulation Of A Carbon Black Suspension Cell Via A Time-Reversed, Double Layer Compute Algorithm, Gregg T. Anderson

Theses and Dissertations

A numerical simulation of a carbon black suspension cell is explored which models a laser-induced plasma within a liquid ethanol medium of approximately 1 mm thickness. The simulation model assumes a laser pulse with a pulse width of approximately 9 nsecs propagating in the left-to-right direction striking the front surface of the medium and focusing to a spot within the liquid volume. When the energy density within a given irradiated volume is sufficiently high, it ignites the carbon particles and generates a large number of free electrons, i.e., a plasma. The plasma couples with the in-coming laser energy on a …


Towards A Game Theory Model Of Information Warfare, David A. Burke Dec 1999

Towards A Game Theory Model Of Information Warfare, David A. Burke

Theses and Dissertations

The repeated game of incomplete information model, a subclass of game theory models, was modified to include aspects of information warfare. The repeated game of incomplete information model was first developed to analyze nuclear weapons disarmament negotiations. The central role of information in this model suggested its applicability to IW, which focuses on the defense and acquisition of information. A randomized experimental design was utilized to determine how people behave in a laboratory IW setting and to test the IW game model's basic predictions. The impact of experience and learning on IW performance was also assessed during the experiment. IW …


Network Security Versus Network Connectivity: A Framework For Addressing The Issues Facing The Air Force Medical Community, Franklin E. Cunningham Jr. Dec 1999

Network Security Versus Network Connectivity: A Framework For Addressing The Issues Facing The Air Force Medical Community, Franklin E. Cunningham Jr.

Theses and Dissertations

The Air Force has instituted Barrier Reef to protect its networks. The Air Force medical community operates network connections that are incompatible with Barrier Reef. To overcome this problem, OASD(HA) directed the Tri-Service Management Program Office (TIMPO) to develop an architecture that protects all military health systems and allows them to link with all three services and outside partners. This research studied the underlying networking issues and formed a framework based on data from network experts from the Air Force's medical centers and their base network organizations. The findings were compared TIMPO and a composite framework was developed that more …


Power, Performance, And Perception (P3): Integrating Usability Metrics And Technology Acceptance Determinants To Validate A New Model For Predicting System Usage, Alan P. Fiorello Dec 1999

Power, Performance, And Perception (P3): Integrating Usability Metrics And Technology Acceptance Determinants To Validate A New Model For Predicting System Usage, Alan P. Fiorello

Theses and Dissertations

Currently, there are two distinct approaches to assist information technology managers in the successful implementation of office automation software. The first approach resides within the field of usability engineering, while the second approach is derived from the discipline of management information systems (MIS). However, neither approach has successfully produced conclusive evidence that explains what characteristics facilitate system use as well as influence user acceptance of the system. This study reports on the validity of a new model, entitled the Power, Performance, Perception (P3) model, that links the constructs of usability engineering to user acceptance. Additionally, speech recognition software (SRS) was …


Evaporation Of Jet Fuels, Charles Eric Hack Dec 1999

Evaporation Of Jet Fuels, Charles Eric Hack

Theses and Dissertations

Determining the fate and transport of JP-8 jet fuel is a complex and important problem. As part of the startup procedures for jet engines, fuel is passed through aircraft engines before combustion is initiated. Because of the extremely low temperatures at northern tier Air Force bases, the unburned fuel does not evaporate readily and may come into contact with ground crew. To determine the amount and duration of contaminant contact, the evaporation of the emitted fuel must be modeled. The amount and composition of the fuel upon reaching the ground crew may be determined by droplet evaporation models that have …


Effects Of Foreign Object Damage From Small Hard Particles On The High-Cycle Fatigue Life Of Ti-6a1-4v, Joseph L. Hamrick Ii Dec 1999

Effects Of Foreign Object Damage From Small Hard Particles On The High-Cycle Fatigue Life Of Ti-6a1-4v, Joseph L. Hamrick Ii

Theses and Dissertations

Thin rectangular samples of Ti-6Al-4V were damaged by four methods to represent foreign object damage found in turbine engine blades: 1) impact with 2 mm and 5 mm diameter glass spheres at 305 m/s, 2) impact with 2 mm and 4 mm diameter steel spheres at 305 m/s, 3) quasi-static displacement controlled indentation using steel chisels with 1 mm, 2 mm and 5 mm diameter tips and 4) shearing notches with a 2 mm diameter chisel point under a quasi-static loading condition. Finite element analysis was used to study the relationship between the stress state created by the plastic damage …


Impact Of Actual Facilitator Alignment, Co-Location, And Video Intervention On The Efficacy Of Distributed Group Support Systems, Brian J. Heberlie, Mary O. Tolbert Dec 1999

Impact Of Actual Facilitator Alignment, Co-Location, And Video Intervention On The Efficacy Of Distributed Group Support Systems, Brian J. Heberlie, Mary O. Tolbert

Theses and Dissertations

The growth of distributed group support systems (GSS) suggests that organizations will continue to bring dispersed groups of people together to make decisions over computer networks. In many instances those groups are temporarily assembled to address a task and then summarily disbanded never to work together again. In order for users to effectively use the GSS issues of trust and control need to be addressed within the GSS design. Users have perceptions about the fairness of structural and social determinants of the GSS design. These perceptions influence both the decision making process and process outcomes. This article shows the negative …


Information System Incidents: The Development Of A Damage Assessment Model, Mark D. Horony Dec 1999

Information System Incidents: The Development Of A Damage Assessment Model, Mark D. Horony

Theses and Dissertations

Information system (IS) incidents are on the rise. With low manning and undertrained information security specialists it is difficult for organizations to stop IS incidents from occurring. Once an incident has occurred it is the IS manager's responsibility to ensure that a full and accurate damage assessment has been accomplished. However, most IS managers lack the necessary tools to assess the damage from an incident. This exploratory thesis developed an IS incident damage assessment model (DAM) that can be part of the IS manager's tool kit. During the development of the model, it became apparent that the model was supported …


Application Of The Interaction Picture To Reactive Scattering In One Dimension, Michael J. Maclachlan Dec 1999

Application Of The Interaction Picture To Reactive Scattering In One Dimension, Michael J. Maclachlan

Theses and Dissertations

The interaction picture is used together with the channel-packet method in a new time-dependent approach to compute reactive scattering matrix elements. The channelpacket method enables the use of the interaction picture for computing reactive S-matrix elements by splitting the computational effort into two parts. First, asymptotic reactant and product wavepackets are individually propagated into the interaction region of the potential to form Moller states. The interaction picture, in contrast to the usual Schrödinger picture of quantum mechanics, is so constructed that a wavefunction that experiences no change in potential (that is, a free-particle wavefunction) remains always fixed, with no translation …


Defining Virtual Interactions: A Taxonomy For Researchers And Practitioners, Glade G. Oxborrow Dec 1999

Defining Virtual Interactions: A Taxonomy For Researchers And Practitioners, Glade G. Oxborrow

Theses and Dissertations

Many uses for virtual technology are being identified by diverse organizational entities around the world. Before these technologies can be fully utilized, it is important to have a common definition and understanding of what is meant by the term virtual. It is also important to understand the structural configurations possible using virtual technology and the types of virtual interactions that may occur using these technologies. This thesis will define the basic premises, structures, and definitions applicable to vial interactions. It also defines various types of virtual interactions that may occur using virtual technology. These designations will help both practitioners and …


Approximation And Optimization Of An Auditory Model For Realization In Vlsi Hardware, Samuel L. Sangregory Dec 1999

Approximation And Optimization Of An Auditory Model For Realization In Vlsi Hardware, Samuel L. Sangregory

Theses and Dissertations

The Auditory Image Model (AIM) is a software tool set developed to functionally model the role of the ear in the human hearing process. AIM includes detailed filter equations for the major functional portions of the ear. Currently, AIM is run on a workstation and requires 10 to 100 times real-time to process audio information and produce an auditory image. An all-digital approximation of the AIM which is suitable for implementation in very large scale integrated circuits is presented. This document details the mathematical models of AIM and the approximations and optimizations used to simplify the filtering and signal processing …


Electrical And Optical Characterization Of Intrinsic And Ion-Implantation Induced Defects In 6h- And 4h-Sic, Michael B. Scott Dec 1999

Electrical And Optical Characterization Of Intrinsic And Ion-Implantation Induced Defects In 6h- And 4h-Sic, Michael B. Scott

Theses and Dissertations

Deep level transient spectroscopy (DLTS), Hall effect, and cathodolummescence (CL) measurements are used to characterize the intrinsic and ion-implantation induced defects in high-temperature (475 and 500 °C) ion-implanted epitaxial n-type 6H- and 4H-SiC, ion-implanted with Cr, Mg, Ar, N, and P atoms. Comparison of room-temperature and high-temperature ion-implanted 6H-SiC:Mg and :Cr indicate the significance of high-temperature ion implantation on the activation of the ion-implanted atoms and damage-recovery of the crystalline lattice. The effects of high-temperature annealing on both damage-recovery and implanted ion activation are detected and analyzed, from 1200 to 1800 °C. Trap parameters of both damage-related and species-related defects …


Reverse Engineering Of Foreign Missiles Via Genetic Algorithm, Jon D. Wollam Dec 1999

Reverse Engineering Of Foreign Missiles Via Genetic Algorithm, Jon D. Wollam

Theses and Dissertations

One mission of the National Air Intelligence Center (NAIC) is the reverse engineering of foreign missile weapon systems from incomplete observational data. In the past, intuition and repeated runs of a missile performance model were required to converge to a solution compatible with observed flight characteristics. This approach can be cumbersome and time consuming, as well as being subject to undesirable influences from the analyst's preconceptions and biases. An alternative approach has been created to apply genetic algorithm (GA) techniques to allow automation of the process, wider exploration of the design space, and more optimal solutions matching the observational data. …


Co-Parenting Influences: A Positive Report For The Millenium, Andrea Chrismer-Still Dec 1999

Co-Parenting Influences: A Positive Report For The Millenium, Andrea Chrismer-Still

Theses

In this correlalional study of later adolescents who experience parental divorce, six co-parenting influences were assessed in an effort to identify predictors and factors that contribute to overall satisfaction with life. Subjects completed a survey comprised of demographic information which included an adaptation of a survey (Silitsky, 1996), a Satisfaction with Life Scale (SWLS) (Diener, E. Simmons, R. Larsen, R. & Griffin, S., 1985), and a Perceived Social Support Family Scale (Pss-Fa) (Procidano, M & Heller, K., 1983). The adapted scale and the PSS-Fa measured perceptions by the later adolescent of their family of origin and their levels of()) parental …


Encapsulation Of Particles Using Brittle Coatings For Subterranean Applications, Aashish L. Bhatia Dec 1999

Encapsulation Of Particles Using Brittle Coatings For Subterranean Applications, Aashish L. Bhatia

Graduate Theses, Dissertations, and Problem Reports (ETD)

The production of a brittle and moisture-resistant coating for particles, which reduce or "break" the viscosity of fracturing fluids, was explored.;The viscosity-reducer was ammonium persulfate. Polyurethane and acrylate coatings were investigated. The coated particles were assessed for dissolution in water before and after being subjected to a compression test. Polyurethane-coated particles had a high leach prior to compression and were considered unsuitable. Acrylate coatings gave much better results. The addition of significant quantities of silica in the coat increased significantly its brittleness. The acrylate formed agglomerates during the coating process. These were easier to break than single particles. These agglomerates …


Determination Of Vitality From A Non-Invasive Biomedical Measurement For Use In Integrated Biometric Devices, Reza Derakhshani Dec 1999

Determination Of Vitality From A Non-Invasive Biomedical Measurement For Use In Integrated Biometric Devices, Reza Derakhshani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Personal identification is a very important issue in today's mobile and electronically networked societies. Among the available measures, fingerprints are the oldest and most widely used. Unfortunately, it is usually possible to deceive automatic fingerprint identification systems by presenting a well-duplicated synthetic or dismembered finger. This project is one method to provide fingerprint vitality authentication in order to solve this problem. Using a sensor that is composed of an array of capacitors, this method identifies the vitality of a fingerprint by detecting a specific changing pattern over the human skin. Mapping the two-dimensional images into one-dimensional signals, two ensembles of …


Data Mining Oipea Database For Waste And Productivity Enhancements In Manufacturing Units, Jaison John Ipe Dec 1999

Data Mining Oipea Database For Waste And Productivity Enhancements In Manufacturing Units, Jaison John Ipe

Graduate Theses, Dissertations, and Problem Reports (ETD)

Small and medium-sized manufacturing plants (those with fewer than 500 employees) represent more than 98 percent of the more than 374,000 establishments in the U.S. manufacturing industry, 64 percent of employees in the total manufacturing labor force, and more than 42 percent of total manufacturing energy consumption.;In 1976 the federal government started funding industrial energy audits for small and medium sized manufacturing firms under the auspices of the Industrial Assessment Centers (IAC) that are spread throughout the U.S. The data collected from the hundreds of energy audits that are conducted each year is collected in a database maintained by the …


Probability Analysis Of Slope Stability, Jennifer Lynn Peterson Dec 1999

Probability Analysis Of Slope Stability, Jennifer Lynn Peterson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The ability of geotechnical engineers to accurately model slope performance is compromised by a variety of factors. The net result of these considerations is that the exact behavior of slopes cannot be accurately predicted. Hence, geotechnical engineers resort to a factor of safety approach to reduce the risk of slope failure. However, the factor of safety approach cannot quantify the probability of failure, or level of risk, associated with a particular design situation.;A probabilistic approach to studying geotechnical issues offers a systematic way to treat uncertainties, especially slope stability. In terms of probability, uncertainties can be related quantitatively to the …


Design And Development Of Fuzzy Expert System For Handy Board, Aditya Kumar Singh Dec 1999

Design And Development Of Fuzzy Expert System For Handy Board, Aditya Kumar Singh

Graduate Theses, Dissertations, and Problem Reports (ETD)

The recent trend in global manufacturing scenario has resulted in the emergence of many innovative techniques that have revolutionized the manufacturing industry as a whole. A lot of states of art advances have been associated with the increasing use of microprocessors in advance manufacturing systems. Out of many the one, which has predominantly captured the real time, behavioral use is the Fuzzy Logic.;Fuzzy logic implementation in real time environment involves the integration of multi-disciplinary area like computer engineering, mechanical and electronic systems tailored towards smart systems that enable a very precise control on the process. The fuzzy logic based project …


Design And Development Of A Microwave-Enhanced Diesel Soot Oxidation System, Bret Allen Rankin Dec 1999

Design And Development Of A Microwave-Enhanced Diesel Soot Oxidation System, Bret Allen Rankin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Diesel particulate matter (PM) emissions have created considerable concern because PM is a suspected carcinogen. Up to this point, improved engine and fuel system design and control schemes have made the use of diesel particulate aftertreatment systems unnecessary for most applications in the United States, but the continued decreasing trend of emissions regulations may necessitate the use of PM filters for many applications.;Many methods have been developed to generate a controlled, reliable regeneration event within PM filters, none of which have been proven to be completely successful. These methods include exhaust throttling, fuel catalysis, filter catalysis, electrical heating, and burner …


Bending Behavior Of Concrete T-Beams Reinforced With Glass Fiber-Reinforced Polymer (Gfrp) Bars, Rajesh Kumar Kalluri Dec 1999

Bending Behavior Of Concrete T-Beams Reinforced With Glass Fiber-Reinforced Polymer (Gfrp) Bars, Rajesh Kumar Kalluri

Graduate Theses, Dissertations, and Problem Reports (ETD)

Concrete slabs are integrally cast with girders or stringers (stiffening system) resulting in floor slabs, bridge decks, footers, retaining structures and others. A portion of slab between a stiffening system acts as flange and bends in unison with the stiffening system, i.e., classic T-beam action. The emphasis of this study is to determine the effective flange width, failure modes, deformability factors, pre- and post-cracking deflections and crack widths at first crack and at ultimate failure of T-beams.;Eight concrete T-beams with two different flange widths and two reinforcement configurations were tested under four point bending to study the factors cited above. …


Molecular-Dynamics Study Of Phase Transitions In Alkali Azides, M. M. Ossowski, John R. Hardy, R. W. Smith Dec 1999

Molecular-Dynamics Study Of Phase Transitions In Alkali Azides, M. M. Ossowski, John R. Hardy, R. W. Smith

John R. Hardy Papers

An account is presented of our studies of the order-disorder phase transitions in KN3, RbN3, and CsN3. These are based on parameter-free interionic potentials based on the Gordon-Kim modified electron-gas formalism extended to molecular ions. We performed static structural relaxations and supercell molecular dynamics and predicted with reasonable accuracy the temperatures for the onset of the transitions. In particular, we address the question of how the N3- ions reorient to yield the transitions. We found the existence of NaCl-type high-temperature phases in disordered KN3 and RbN3 and argue that this …


Thermal Degradation Of Blends Of Polystyrene And Poly(Sodium 4-Styrenesulfonate) And The Copolymer, Poly(Styrene-Co-Sodium 4-Styrenesulfonate), Qiang Yao, Charles Wilkie Dec 1999

Thermal Degradation Of Blends Of Polystyrene And Poly(Sodium 4-Styrenesulfonate) And The Copolymer, Poly(Styrene-Co-Sodium 4-Styrenesulfonate), Qiang Yao, Charles Wilkie

Chemistry Faculty Research and Publications

The thermal degradation of blends and copolymers of styrene with styrenesulfonic acid has been studied using thermogravimetric analysis, TGA/FTIR, and cone calorimetry. The blends have enhanced thermal stability relative to virgin polystyrene but there is no enhancement in thermal stability for the copolymers. Apparently, it is necessary to have adjacent sulfonic acid groups in order to permit the formation of a graphite-like char which can provide thermal protection to the polymer. It is necessary to have a good match in degradation temperatures of the two components if one is to have significantly enhanced thermal stability.


Measurement Of The B0B̅0 Oscillation Frequency Using L-D*+ Pairs And Lepton Flavor Tags, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Dec 1999

Measurement Of The B0B̅0 Oscillation Frequency Using L-D*+ Pairs And Lepton Flavor Tags, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

The oscillation frequency Δmd of B0B̅0 mixing is measured using the partially reconstructed semileptonic decay B̅0→l- ν̅ D*+X. The data sample was collected with the CDF detector at the Fermilab Tevatron collider during 1992–1995 by triggering on the existence of two lepton candidates in an event, and corresponds to about 110 pb-1 of p̅p collisions at √s =1.8 TeV. We estimate the proper decay time of the B̅0 meson from the measured decay length and reconstructed momentum of the l-D*+ system. The charge of …


The Dayton Its Demonstration Project: Simulating Existing Conditions, Jill A. Swaynos, Nikiforos Stamatiadis Dec 1999

The Dayton Its Demonstration Project: Simulating Existing Conditions, Jill A. Swaynos, Nikiforos Stamatiadis

Kentucky Transportation Center Research Report

The Miami Valley Regional Planning Commission is incorporating an Advanced Traveler Information System to alleviate real-time traffic problems associated with special events at the Ervin J. Nutter Center of the Wright State University. This study of the existing conditions is part of the evaluation plan and addresses two tasks: 1) documentation of the existing conditions; and 2) definition of measures of effectiveness. The existing conditions were depicted with the use of a computer simulation software package, Traffic Software Integrated System and separate scenarios were modeled for three existing conditions: ingress and egress for a special event and a major shopping …


Stress At A Juvenile Detention Center: Identifying Stressors And Examining The Coping Process, Matthew J. Schmid Dec 1999

Stress At A Juvenile Detention Center: Identifying Stressors And Examining The Coping Process, Matthew J. Schmid

Masters Theses

In the examination of the literature dealing with stress as it relates to corrections, normally "juvenile corrections workers are not considered, due to the dearth of stress-related research" (Huckabbe, 1992, p. 479). This thesis is a qualitative project designed to analyze detention workers' views on stress. I was interested in finding out the following two things: (1) the workers' identification of the major stressors in their job, and (2) the ways the workers coped with the stressors identified.

Structured interviews were conducted with one third (12) of the detention staff that worked at a forty bed juvenile detention center in …


Molecular Dynamics Simulation Study Of The Stability And Conformation Of Spin-Probe Labeled Dnas, Eva Darian Dec 1999

Molecular Dynamics Simulation Study Of The Stability And Conformation Of Spin-Probe Labeled Dnas, Eva Darian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nitroxide based spin-probes, observable by ESR, have been used to study protein structure and protein-substrate interactions. More recently, spin-probe labeled DNAs have been introduced to study its structure and dynamics. Molecular modeling has proven to be an increasingly powerful tool for studying structure and dynamics of biologically interesting, molecules. As part of our work, we have conducted molecular dynamics simulations on both double-stranded (ds) and triple-stranded or triplex (tx) spin-probe labeled DNAs for comparison with unmodified ones and to design new probes. Nitroxide spin-labeled analogue of thymidine in which the methyl group is replaced by an acetylene-tethered nitroxide (T*) was …


Physiological And Genetic Mechanism(S) Of Cold Acclimation In Rhododendron, Chon Chong Lim Dec 1999

Physiological And Genetic Mechanism(S) Of Cold Acclimation In Rhododendron, Chon Chong Lim

Graduate Theses, Dissertations, and Problem Reports (ETD)

An in vitro laboratory protocol for assessing cold hardiness (CH) in rhododendrons based on electrolyte-leakage was developed. The raw leakage data were transformed into percent-adjusted injury, which showed high correlation with injury data based on visual observations. The percent-adjusted injury data---fitted to the Gompertz function coupled with the Jackknife method---allowed for reliable and statistically sound estimations of Rhododendron leaf freezing-tolerance (LFT). Utilizing this method, Tmax values for Rhododendron cultivars, species, and populations were determined and ranked relatively. Our observation of a continuous distribution of LFT in F2 and backcross (BC) populations derived from a R. catawbiense x R. fortunei cross …


Performance Evaluation Of Exhaust Aftertreatment Devices Used For Emissions Control On Diesel Engines Employed In Underground Coal Mines, Daniel K. Carder Dec 1999

Performance Evaluation Of Exhaust Aftertreatment Devices Used For Emissions Control On Diesel Engines Employed In Underground Coal Mines, Daniel K. Carder

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was initiated to assist the WV Diesel Equipment Commission in its promulgation of initial rules, requirements, and standards governing the operation of diesel-powered equipment in underground coal mines. Four different engines and various exhaust after treatment devices that represent current levels of in-use technology were selected for performance evaluation. Both eddy-current and water-brake dynamometers were used to load the engines according to an ISO 8-Mode test cycle. Experimental emissions data, sampled from a full-flow dilution tunnel, suggests that particulate traps can reduce the mass emission rates of particulate matter (DPM) by nearly 90%, while reductions in fuel sulfur …


Decision Support Tool For Costing Of The Pultrusion Process, Taher Badrudin Patrawala Dec 1999

Decision Support Tool For Costing Of The Pultrusion Process, Taher Badrudin Patrawala

Graduate Theses, Dissertations, and Problem Reports (ETD)

The use of advanced composites has grown over the last two decades. These high strength, low weight materials can now be found in many structural applications, including bridges. However, the substitution of plastics for conventional materials, such as steel, is governed by engineering constraints and cost competitiveness. A brief discussion of the process variables and engineering constraints is presented in the first chapter. To analyze the latter and to identify cost centers in production more readily, a computerized cost model was developed. This model estimates the cost of producing components by the pultrusion process.;The technical cost modeling methodology employed involves …