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The Willingness To Pay For The Detection And Treatment Of Vulnerable Plaque Related To Heart Attacks, Patricia L. Ryan Jan 2007

The Willingness To Pay For The Detection And Treatment Of Vulnerable Plaque Related To Heart Attacks, Patricia L. Ryan

University of Kentucky Doctoral Dissertations

Recent medical studies have led cardiologists to revise theories regarding the cause of heart attacks. Rather than a gradual clogging of the arteries, eruption of a vulnerable plaque is thought to be the cause of approximately 75% of all heart attacks. As a result, traditional risk factors are no longer sufficient indicators of who is at risk for a heart attack. Therefore, this research investigates the willingness to pay (WTP) for a new, hypothetical detection (screening) and treatment method for vulnerable plaque. For this study, two survey instruments were developed that take advantage of the visual and interactive aspects of …


Numerical Analysis Of Metal Transfer In Gas Metal Arc Welding, Ge Wang Jan 2007

Numerical Analysis Of Metal Transfer In Gas Metal Arc Welding, Ge Wang

University of Kentucky Doctoral Dissertations

In gas metal arc welding (GMAW), metal transfer plays a crucial role in determining the quality of the resultant weld. In the present dissertation, a numerical model with advanced computational fluid dynamics (CFD) techniques has been developed first in order to provide better numerical results. It includes a two-step projection method for solving the incompressible fluid flow; a volume of fluid (VOF) method for capturing free surface; and a continuum surface force (CSF) model for calculating surface tension. The Gauss-type current density distribution is assumed as the boundary condition for the calculation of the electromagnetic force. The droplet profiles, electric …


Abstract For A Look At Attitude And Achievement As A Result Of Self-Regulated Learning In The Algebra I Classroom, Darin Craig Schroeder Jan 2007

Abstract For A Look At Attitude And Achievement As A Result Of Self-Regulated Learning In The Algebra I Classroom, Darin Craig Schroeder

University of Kentucky Doctoral Dissertations

Not often do mathematics teachers instruct to improve students' attitudes toward mathematics. The pressures to cover the state-mandated curriculum drive teachers to instruct for procedural understanding with few connections. The lack of real-life connections results in students with low motivation toward mathematics and results in poor mathematics attitude (Ma andamp; Kishor, 1997). The purpose of this mixed-methods research is to examine self-regulated learning as an instructional technique aimed at increasing mathematical attitudes while also increasing achievement and to reveal barriers to its implementation in the classroom.The research study involved an intervention in a Mid-South urban high school at the 9th …


New Bioinformatic Techniques For The Analysis Of Large Datasets, Justin Clay Harris Jan 2007

New Bioinformatic Techniques For The Analysis Of Large Datasets, Justin Clay Harris

University of Kentucky Doctoral Dissertations

A new era of chemical analysis is upon us. In the past, a small number of samples were selected from a population for use as a statistical representation of the entire population. More recently, advancements in data collection rate, computer memory, and processing speed have allowed entire populations to be sampled and analyzed. The result is massive amounts of data that convey relatively little information, even though they may contain a lot of information. These large quantities of data have already begun to cause bottlenecks in areas such as genetics, drug development, and chemical imaging. The problem is straightforward: condense …


Characterization And Flow Physics Of Plasma Synthetic Jet Actuators, Arvind Santhanakrishnan Jan 2007

Characterization And Flow Physics Of Plasma Synthetic Jet Actuators, Arvind Santhanakrishnan

University of Kentucky Doctoral Dissertations

Plasma synthetic jet actuators are investigated experimentally, in which the geometrical design of single dielectric barrier discharge (SDBD) plasma actuators is modified to produce zero-mass flux jets similar to those created by mechanical devices. The SDBD plasma actuator consists of two rectangular electrodes oriented asymmetrically and separated by a layer of dielectric material. Under an input of high voltage, high frequency AC or pulsed DC, a region of plasma is created in the interfacial air gap on account of electrical breakdown of the ambient air. A coupling between the electric field in the plasma and the neutral air near the …


Essays In Health Economics, Rachel Pauline Lange Jan 2007

Essays In Health Economics, Rachel Pauline Lange

University of Kentucky Doctoral Dissertations

Health and health care are dominant economic and political issues in the United States and many other countries. This dissertation contains two essays addressing different subjects within the field of health economics. The first essay is labor market oriented: An Economic Analysis of the Effects of Obesity on Wages. It examines the effects of overweight and obesity on the wages of men and women. The second essay, An Economic Analysis of the Impact on Health Care of Certain Medicare Provisions of the Balanced Budget Act of 1997 examines changes in the treatment of Medicare patients in light of reimbursement changes …


Gmres On A Tridiagonal Toeplitz Linear System, Wei Zhang Jan 2007

Gmres On A Tridiagonal Toeplitz Linear System, Wei Zhang

University of Kentucky Doctoral Dissertations

The Generalized Minimal Residual method (GMRES) is often used to solve a nonsymmetric linear system Ax = b. But its convergence analysis is a rather difficult task in general. A commonly used approach is to diagonalize A = XΛX-1 and then separate the study of GMRES convergence behavior into optimizing the condition number of X and a polynomial minimization problem over As spectrum. This artificial separation could greatly overestimate GMRES residuals and likely yields error bounds that are too far from the actual ones. On the other hand, considering the effects of both As spectrum and the conditioning of X …


Interactions Between Structures In The Appalachian And Ouachita Foreland Beneath The Gulf Coastal Plain, Donald Matthew Surles Jan 2007

Interactions Between Structures In The Appalachian And Ouachita Foreland Beneath The Gulf Coastal Plain, Donald Matthew Surles

University of Kentucky Doctoral Dissertations

In Alabama, the Paleozoic Appalachian thrust belt plunges southwest beneath the Mesozoic-Cenozoic Gulf Coastal Plain. In Arkansas, the Paleozoic Ouachita thrust belt plunges southeast beneath the Coastal Plain. The strikes of the exposed thrust belts suggest an intersection beneath the Coastal Plain. Well data and seismic reflection profiles confirm the strike and intersection of the thrust belts, and provide information to determine the structure and general stratigraphy of each thrust belt. In east-central Mississippi, the Appalachian thrust belt curves from the regional northeast trace to westward at the intersection with the southeastern terminus of the Ouachita thrust belt, to northwest …


Polymorphism Of Four Enantiotropic Crystalline Systems Containing Ni(Ii), H2O, 15-Crown-5 And No3-, Maxime Andre Siegler Jan 2007

Polymorphism Of Four Enantiotropic Crystalline Systems Containing Ni(Ii), H2O, 15-Crown-5 And No3-, Maxime Andre Siegler

University of Kentucky Doctoral Dissertations

The series of compounds [M(H2O)2(15-crown-5)](NO3)2, M = Mg, Mn, Co, Cu and Zn, has been extended to include two new phases for M = Fe and two new phases for M = Ni. The system [M(H2O)2(15-crown-5)](NO3)2 is remarkable for having many high-Z’ phases (Z’ > 1) with similar packing and for having solid-solid phase transitions through which there is no significant loss of crystallinity. The synthesis of the analogous Ni complex was carried out. Single-crystal X-ray diffraction showed …


Characterization Of Colloidal Nanoparticle Aggregates Using Light Scattering Techniques, Mehmet Kozan Jan 2007

Characterization Of Colloidal Nanoparticle Aggregates Using Light Scattering Techniques, Mehmet Kozan

University of Kentucky Doctoral Dissertations

Light scattering is a powerful characterization tool for determining shape, size, and size distribution of fine particles, as well as complex, irregular structures of their aggregates. Small angle static light scattering and elliptically polarized light scattering techniques produce accurate results and provide real time, non-intrusive, and in-situ observations on prevailing process conditions in three-dimensional systems. As such, they complement conventional characterization tools such as SEM and TEM which have their known disadvantages and limitations. In this study, we provide a thorough light scattering analysis of colloidal tungsten trioxide (WO3) nanoparticles in the shape of irregular nanospheres and cylindrical nanowires, and …


The Impact Of Domestic Policies On International Competitiveness, Md. Ashfaqul Islam Babool Jan 2007

The Impact Of Domestic Policies On International Competitiveness, Md. Ashfaqul Islam Babool

University of Kentucky Doctoral Dissertations

The impact of domestic policy regulations and standards on trade has been at the forefront of global policy during the past decade. Every country develops their own policies and standards that differ from country to country. These differences create problems for manufacturing industries, especially in major exporting countries. This study overviews the policy context driving standards in the manufacturing industries. The study consists of three different articles that attempt to examine the role of technical regulations and standards and their relationship with trade using different econometric models In the first article, the standard factor endowment approach is employed to explain …


Simulations-Guided Design Of Process Analytical Sensor Using Molecular Factor Computing, Bin Dai Jan 2007

Simulations-Guided Design Of Process Analytical Sensor Using Molecular Factor Computing, Bin Dai

University of Kentucky Doctoral Dissertations

Many areas of science now generate huge volumes of data that present visualization, modeling, and interpretation challenges. Methods for effectively representing the original data in a reduced coordinate space are therefore receiving much attention. The purpose of this research is to test the hypothesis that molecular computing of vectors for transformation matrices enables spectra to be represented in any arbitrary coordinate system. New coordinate systems are selected to reduce the dimensionality of the spectral hyperspace and simplify the mechanical/electrical/computational construction of a spectrometer. A novel integrated sensing and processing system, termed Molecular Factor Computing (MFC) based near infrared (NIR) spectrometer, …


Rule Extraction To Establish Criteria For Minicell Design In Mass Customization Manufacturing, Smitha Thuramalla Jan 2007

Rule Extraction To Establish Criteria For Minicell Design In Mass Customization Manufacturing, Smitha Thuramalla

University of Kentucky Master's Theses

Minicell-based manufacturing system is used in identifying best minicell designs. The existing method of minicell design generates best minicell designs by designing and scheduling minicells simultaneously. While in this research designing of minicells and scheduling of jobs in minicells is done separately. This research evaluates the effectiveness of hierarchical approach and compares with simultaneous method. Minicell designs with respect to average flow times and machine capacities and both are identified in a multi-stage flow shop environment. Rules for the extraction of good minicell designs in mass customization manufacturing systems are also established.


Instructional Communication Matters: A Test Of Knowledge Acqusition Theory (Kat) From A Message-Oriented Receiver Perspective, Robert Joseph Trader Jan 2007

Instructional Communication Matters: A Test Of Knowledge Acqusition Theory (Kat) From A Message-Oriented Receiver Perspective, Robert Joseph Trader

University of Kentucky Doctoral Dissertations

This dissertation encourages adoption of a message-oriented receiver perspective when developing new instructional communication theories and proposes a causal-process model derived from Knowledge Acquisition Theory to demonstrate how this perspective can be used to predict student cognitive learning outcomes. Three hypotheses are generated to test the propositions of the derived model. The first hypothesis seeks to determine which dimensions of instructional message clarity and course content relevance best predict student interactions with instructional content. The second hypothesis predicts that student self-reported knowledge gains are a function of student interactions with content. The third hypothesis predicts that a significant proportion of …


Computer Simulation And Modeling Of Physical And Biological Processes Using Partial Differential Equations, Wensheng Shen Jan 2007

Computer Simulation And Modeling Of Physical And Biological Processes Using Partial Differential Equations, Wensheng Shen

University of Kentucky Doctoral Dissertations

Scientific research in areas of physics, chemistry, and biology traditionally depends purely on experimental and theoretical methods. Recently numerical simulation is emerging as the third way of science discovery beyond the experimental and theoretical approaches. This work describes some general procedures in numerical computation, and presents several applications of numerical modeling in bioheat transfer and biomechanics, jet diffusion flame, and bio-molecular interactions of proteins in blood circulation.

A three-dimensional (3D) multilayer model based on the skin physical structure is developed to investigate the transient thermal response of human skin subject to external heating. The temperature distribution of the skin is …


Requirements Tracing Using Information Retrieval, Senthil Karthikeyan Sundaram Jan 2007

Requirements Tracing Using Information Retrieval, Senthil Karthikeyan Sundaram

University of Kentucky Doctoral Dissertations

It is important to track how a requirement changes throughout the software lifecycle. Each requirement should be validated during and at the end of each phase of the software lifecycle. It is common to build traceability matrices to demonstrate that requirements are satisfied by the design. Traceability matrices are needed in various tasks in the software development process. Unfortunately, developers and designers do not always build traceability matrices or maintain traceability matrices to the proper level of detail. Therefore, traceability matrices are often built after-the-fact. The generation of traceability matrices is a time consuming, error prone, and mundane process. Most …


The First Grade Private School Sector: Taxonomy, Choice, And Achievement, Christine Berry Lloyd Jan 2007

The First Grade Private School Sector: Taxonomy, Choice, And Achievement, Christine Berry Lloyd

University of Kentucky Doctoral Dissertations

Studies focusing on Catholic schools as a proxy for all private education or all private religious education miss important variances within the private school sector, especially at the first grade level. The implication of this is that the vast majority of secondary school choice studies are incomplete; the elementary schooling decision of the parents should be included for all secondary school choice analyses. I augment the scope of a households first grade schooling choice by offering a rich model that includes the public schooling option and the most detailed typology of private schools to date: Catholic, Evangelical or Fundamental Protestant, …


Helium (E, 2e) Coplanar And Out-Of-Plane Experiments, Bruno A. Deharak Jan 2007

Helium (E, 2e) Coplanar And Out-Of-Plane Experiments, Bruno A. Deharak

University of Kentucky Doctoral Dissertations

The detection of sound sources with microphone arrays can be enhanced through processing individual microphone signals prior to the delay and sum operation. One method in particular, the Phase Transform (PHAT) has demonstrated improvement in sound source location images, especially in reverberant and noisy environments. Recent work proposed a modification to the PHAT transform that allows varying degrees of spectral whitening through a single parameter, andamp;acirc;, which has shown positive improvement in target detection in simulation results. This work focuses on experimental evaluation of the modified SRP-PHAT algorithm. Performance results are computed from actual experimental setup of an 8-element perimeter …


Synthesis And Reactivity Of Membrane-Supported Bimetallic Nanoparticles For Pcb And Trichloroethylene Dechlorination, Jian Xu Jan 2007

Synthesis And Reactivity Of Membrane-Supported Bimetallic Nanoparticles For Pcb And Trichloroethylene Dechlorination, Jian Xu

University of Kentucky Doctoral Dissertations

Nanosized metal particles have become an important class of materials in the field of catalysis, optical, electronic, magnetic and biological devices due to the unique physical and chemical properties. This research deals with the synthesis of structured bimetallic nanoparticles for the dechlorination of toxic organics. Nanoparticle synthesis in aqueous phase for dechlorination studies has been reported. However, in the absence of polymers or surfactants particles can easily aggregate into large particles with wide size distribution. In this study, we report a novel in-situ synthesis method of bimetallic nanoparticles embedded in polyacrylic acid (PAA) functionalized microfiltration membranes by chemical reduction of …


A Visualization Tool For Cross-Experiment Gene Expression Analysis Of C. Elegans, Lin Xue Jan 2007

A Visualization Tool For Cross-Experiment Gene Expression Analysis Of C. Elegans, Lin Xue

University of Kentucky Master's Theses

Forty-six genomic gene expression studies of free living soil nematode C. eleganshave been published. To facilitate exploratory analysis of those studies, we constructed adatabase containing all the published C. elegans expression datasets. A Perl CGIprogram, called Microarray Analysis Display (MAdisplay), allows gene expressionclustergrams of any combination of entered genes and datasets to be viewed(http://elegans.uky.edu/gl/madisplay). Perl programs were used to preprocess the rawdata from different sources into a common format and to transform the data to displaythe expression changes relative to each experiment's controls. Three hundred lists ofgenes from figures and tables were extracted from the publications and made available inthe …


Numerical Simulation Of Two Flow Control Approaches For Low Reynolds Number Applications, Daniel A. Reasor Jr. Jan 2007

Numerical Simulation Of Two Flow Control Approaches For Low Reynolds Number Applications, Daniel A. Reasor Jr.

University of Kentucky Master's Theses

Current research in experimental and computational fluid dynamics is focused in the area of flow control. Flow control devices are usually classified as either passive or active. Plasma actuators are active flow control devices that require input from an external power source. Current efforts have modeled the effects of plasma actuators as a body force near the electrode. The research presented herein focuses on modeling the fluid-plasma interaction seen in dielectric barrier discharge plasma actuators as a body force vector in the region above the embedded electrode using computational fluid dynamics (CFD). This body force is modeled as the product …


Influence Of Surface Roughness Of Copper Substrate On Wetting Behavior Of Molten Solder Alloys, Dinesh Reddy Nalagatla Jan 2007

Influence Of Surface Roughness Of Copper Substrate On Wetting Behavior Of Molten Solder Alloys, Dinesh Reddy Nalagatla

University of Kentucky Master's Theses

The objective of this study is to understand the effect of surface roughness of the Cu substrate on the wetting of molten solder alloys. Eutectic Sn-Pb, pure Sn and eutectic Sn-Cu solder alloys and Cu substrates with different surface finish viz., highly polished surface, polished surface and unpolished surface were used in this work. Highly polished surface was prepared in Metallography lab, University of Kentucky while other two substrates were obtained from a vendor. Surface roughness properties of each substrate were measured using an optical profilometer. Highly polished surface was found to be of least surface roughness, while unpolished surface …


An Approach To Inverse Modeling Through The Integration Of Artificial Neural Networks And Genetic Algorithms, Kirthi Bedida Jan 2007

An Approach To Inverse Modeling Through The Integration Of Artificial Neural Networks And Genetic Algorithms, Kirthi Bedida

University of Kentucky Master's Theses

A hybrid model integrating predictive capabilities of Artificial Neural Network (ANN) and optimization feature of Genetic Algorithm (GA) is developed for the purpose of inverse modeling. The proposed approach is applied to Superplastic forming of materials to predict the material properties which characterize the performance of a material. The study is carried out on two problems. For the first problem, ANN is trained to predict the strain rate sensitivity index m given the temperature and the strain rate. The performance of different gradient search methods used in training the ANN model is demonstrated. Similar approach is used for the second …


Numerical Investigation And Parallel Computing For Thermal Transport Mechanism During Nanomachining, Ravi R. Kumar Jan 2007

Numerical Investigation And Parallel Computing For Thermal Transport Mechanism During Nanomachining, Ravi R. Kumar

University of Kentucky Master's Theses

Nano-scale machining, or Nanomachining is a hybrid process in which the total thermal energy necessary to remove atoms from a work-piece surface is applied from external sources. In the current study, the total thermal energy necessary to remove atoms from a work-piece surface is applied from two sources: (1) localized energy from a laser beam focused to a micron-scale spot to preheat the work-piece, and (2) a high-precision electron-beam emitted from the tips of carbon nano-tubes to remove material via evaporation/sublimation. Macro-to-nano scale heat transfer models are discussed for understanding their capability to capture and its application to predict the …


Faster Dynamic Programming For Markov Decision Processes, Peng Dai Jan 2007

Faster Dynamic Programming For Markov Decision Processes, Peng Dai

University of Kentucky Master's Theses

Markov decision processes (MDPs) are a general framework used by Artificial Intelligence (AI) researchers to model decision theoretic planning problems. Solving real world MDPs has been a major and challenging research topic in the AI literature. This paper discusses two main groups of approaches in solving MDPs. The first group of approaches combines the strategies of heuristic search and dynamic programming to expedite the convergence process. The second makes use of graphical structures in MDPs to decrease the effort of classic dynamic programming algorithms. Two new algorithms proposed by the author, MBLAO* and TVI, are described here.


Power System Fault Detection And Classification By Wavelet Transforms And Adaptive Resonance Theory Neural Networks, Karthikeyan Kasinathan Jan 2007

Power System Fault Detection And Classification By Wavelet Transforms And Adaptive Resonance Theory Neural Networks, Karthikeyan Kasinathan

University of Kentucky Master's Theses

This thesis aims at detecting and classifying the power system transmission line faults. To deal with the problem of an extremely large data set with different fault situations, a three step optimized Neural Network approach has been proposed. The approach utilizes Discrete Wavelet Transform for detection and two different types of self-organized, unsupervised Adaptive Resonance Theory Neural Networks for classification. The fault scenarios are simulated using Alternate Transients Program and the performance of this highly improved scheme is compared with the existing techniques. The simulation results prove that the proposed technique handles large data more efficiently and time of operation …


Analytical Methods For Transport Equations In Similarity Form, Abhishek Tiwari Jan 2007

Analytical Methods For Transport Equations In Similarity Form, Abhishek Tiwari

University of Kentucky Master's Theses

We present a novel approach for deriving analytical solutions to transport equations expressedin similarity variables. We apply a fixed-point iteration procedure to these transformedequations by formally solving for the highest derivative term and then integrating to obtainan expression for the solution in terms of a previous estimate. We are able to analyticallyobtain the Lipschitz condition for this iteration procedure and, from this (via requirements forconvergence given by the contraction mapping principle), deduce a range of values for the outerlimit of the solution domain, for which the fixed-point iteration is guaranteed to converge.


Kfgc Forage Spokesman Contest, Todd A. Clark, Farms, Inc., Robey Farms Nov 2006

Kfgc Forage Spokesman Contest, Todd A. Clark, Farms, Inc., Robey Farms

Kentucky Grazing Conference

No abstract provided.


New Options For Extending Grazing, Edward N. Ballard Nov 2006

New Options For Extending Grazing, Edward N. Ballard

Kentucky Grazing Conference

Feed costs represent the major cost in most livestock production systems. A recently completed analysis of 225 Standardized Performance Analysis (SPA) Beef Cow Records on herds in Illinois and Iowa showed that feed cost was the overriding factor determining profitability, explaining over 57 percent of the herd-to-herd variation.


Dollars & Cents Of Intensive Grazing, Kenneth H. Burdine Nov 2006

Dollars & Cents Of Intensive Grazing, Kenneth H. Burdine

Kentucky Grazing Conference

A rotational grazing system can generally be defined as the use of several pastures with one being grazed while the others are rested. On the contrary, conventional or continuous grazing systems allow livestock access to the entire pasture area and let them decide where, what, and how long to graze. In most cases, Kentucky pastures employing continuous grazing systems are too large for efficient management and forage utilization. In such instances, cattle overgraze more palatable forages and areas close to shade and water, while other sections of the pasture are underutilized. This leads to lower animal output per acre than …