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2006

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Investigation Of Protein-Dna Contacts In The Saccharomyces Cerevisiae Rna Polymerase Iii Recruitment Factor (Tfiiib) Complex And Effects Of Promoter Topology On Transcription, Nick Dimitrios Tsihlis Jan 2006

Investigation Of Protein-Dna Contacts In The Saccharomyces Cerevisiae Rna Polymerase Iii Recruitment Factor (Tfiiib) Complex And Effects Of Promoter Topology On Transcription, Nick Dimitrios Tsihlis

LSU Doctoral Dissertations

The TATA-binding protein (TBP) is required for transcription by all three nuclear RNA polymerase systems. TBP binds the TATA box (consensus sequence TATAa/tAa/tN) and induces an ~80° bend in the DNA. To achieve recruitment of Saccharomyces cerevisiae RNA polymerase III, TBP is associated with two additional factors, Brf1 and Bdp1, to form initiation factor TFIIIB. This study focuses on interactions between the proteins and DNA in TFIIIB, and effects of promoter topology on transcription. Previous data suggests that the structure or dynamics of the TBP-DNA complex may be altered upon entry of Brf1 and Bdp1 into the complex. Here, an …

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Fabrication, Characterization And Properties Of Hiercchically Ordered Nanocomposites, Avinash Dundigalla Jan 2006

Fabrication, Characterization And Properties Of Hiercchically Ordered Nanocomposites, Avinash Dundigalla

LSU Doctoral Dissertations

The objectives of this research are to study the structure, morphology and properties of poly(ethylene-oxide) (PEO)-clay nanocomposites using various imaging techniques. Optical Microscopy, Scanning Electron Microscopy, Environmental Scanning Electron Microscopy and Atomic Force Microscopy are used to image structures on all length scales. Complementary scattering experiments are discussed along with preliminary differential scanning calorimetry and Fourier Transform Infrared spectroscopy results. In particular we investigated the multilayered structures of PEO-Laponite and PEO-Montmorillonite multilayered films made from solution. The shear orientation of a polymer-clay network in solution combined with simultaneous solvent evaporation leads to supramolecular multilayer formation in the film. The resulting …

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The Role Of Technology In The Interactions Between Secondary School Library Media Specialists And Teachers, Shirley Benson Mcdonald Jan 2006

The Role Of Technology In The Interactions Between Secondary School Library Media Specialists And Teachers, Shirley Benson Mcdonald

LSU Doctoral Dissertations

Statewide studies of school library media centers in at least sixteen states (other than Louisiana) indicate that effective school library media center programs have a positive impact on student achievement. According to these studies, effective school library media centers have: (a) a qualified library media specialist, (b) adequate support staff, (c) current and large collections, (d) access to information technology that is integrated into the curriculum, and (e) time for collaboration with the faculty. This study was developed to explore the role of technology in the collaborations between school library media specialists and teachers. Data revealed that interactions between school …

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Summary Of Lecture Recital: Bright Sheng's Selected Chamber Music For Strings: Two Violin Solos, And Two String Quartets, Mei-Mei Wei Jan 2006

Summary Of Lecture Recital: Bright Sheng's Selected Chamber Music For Strings: Two Violin Solos, And Two String Quartets, Mei-Mei Wei

LSU Doctoral Dissertations

Bright Sheng was born in Shanghai, China, in 1955, and became one of America’s leading composers in the twentieth-century. Bright Sheng’s orchestral music, opera and chamber music is frequently performed throughout the world. His musical language combines Chinese folk music and Western techniques--the meeting of East and West. This essay will discuss Bright Sheng’s The Stream Flows for solo violin (1990), Three Fantasies for Violin and Piano (2006), String Quartet No.3 (1993), and String Quartet No.4 Silent Tempo (2000). These works represent Sheng’s chamber music for strings. This essay will be organized as follows: Chapter 1 will provide Bright Sheng’s …

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How Principal Participation In An Online Community Of Practice Impacts The Professional Development Experience Of Middle School Teachers, Cynthia Beatty Vavasseur Jan 2006

How Principal Participation In An Online Community Of Practice Impacts The Professional Development Experience Of Middle School Teachers, Cynthia Beatty Vavasseur

LSU Doctoral Dissertations

This study provided insights about incorporating an online community of practice into a professional development program designed to facilitate the instructional implementation of technology. Two middle schools in a southern state served as a comparative case study where this model of professional development was implemented. The primary goal of this research was to gain understanding of how principals interact with teachers and the roles principals assume during these interactions. A second goal was to determine how teachers perceived principal participation and how their levels of competence and efficacy were influenced by this experience. During four weeks of implementation principals participated …

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Ontology-Based Methodology For Error Detection In Software Design, Allyson M. Hoss Jan 2006

Ontology-Based Methodology For Error Detection In Software Design, Allyson M. Hoss

LSU Doctoral Dissertations

Improving the quality of a software design with the goal of producing a high quality software product continues to grow in importance due to the costs that result from poorly designed software. It is commonly accepted that multiple design views are required in order to clearly specify the required functionality of software. There is universal agreement as to the importance of identifying inconsistencies early in the software design process, but the challenge is how to reconcile the representations of the diverse views to ensure consistency. To address the problem of inconsistencies that occur across multiple design views, this research introduces …

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Intercarrier Interference Suppression For The Ofdm Systems In Time-Varying Multipath Fading Channels, Xiaozhou Huang Jan 2006

Intercarrier Interference Suppression For The Ofdm Systems In Time-Varying Multipath Fading Channels, Xiaozhou Huang

LSU Doctoral Dissertations

Due to its spectral efficiency and robustness over the multipath channels, orthogonal frequency division multiplexing (OFDM) has served as one of the major modulation schemes for the modern communication systems. In the future, the wireless OFDM systems are expected to operate at high carrier-frequencies, high speed and high throughput mobile reception, where the fasting time-varying fading channels are encountered. The channel variation destroys the orthogonality among the subcarriers and leads to the intercarrier interference (ICI). ICI poses a significant limitation to the wireless OFDM systems. The aim of this dissertation is to find an efficient method of providing reliable communication …

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Electrodeposited Metal Matrix Nanocomposites As Thin Films And High Aspect Ratio Microstructures For Mems, Alonso Lozano Morales Jan 2006

Electrodeposited Metal Matrix Nanocomposites As Thin Films And High Aspect Ratio Microstructures For Mems, Alonso Lozano Morales

LSU Doctoral Dissertations

The electrodeposition of metal-matrix nanocomposites as thin film and high aspect ratio microstructures (HARM’s) for MicroElectroMechanical Systems (MEMS) components is examined. The effect of -Al2O3 nanopowder on copper reduction from acidic and basic electrolytes is examined with rotating disk electrodes (RDE’s). At pH 0.2, regions of copper inhibition and enhancement are identified in the kinetic regime. Low particle loading (12.5 g/L) results in an inhibited copper rate, while, high particle concentration (60 g/L) does both, inhibits the rate at low overpotentials and accelerates it at higher overpotentials, depending on the electrode rotation rate. At pH 8 the presence of particles …

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Compiler Optimization Techniques For Scheduling And Reducing Overhead, Tong-Chai Wang Jan 2006

Compiler Optimization Techniques For Scheduling And Reducing Overhead, Tong-Chai Wang

LSU Doctoral Dissertations

Exploiting parallelism in loops in programs is an important factor in realizing the potential performance of processors today. This dissertation develops and evaluates several compiler optimizations aimed at improving the performance of loops on processors. An important feature of a class of scientific computing problems is the regularity exhibited by their access patterns. Chapter 2 presents an approach of optimizing the address generation of these problems that results in the following: (i) elimination of redundant arithmetic computation by recognizing and exploiting the presence of common sub-expressions across different iterations in stencil codes; and (ii) conversion of as many array references …

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Theoretical And Experimental Study On Cable Vibration Reduction With A Tmd-Mr Damper, Wenjie Wu Jan 2006

Theoretical And Experimental Study On Cable Vibration Reduction With A Tmd-Mr Damper, Wenjie Wu

LSU Doctoral Dissertations

Stay cables are vulnerable to dynamic excitations because of their low intrinsic damping. Excessive cable vibrations cause frequent maintenance and are detrimental to the safety of the entire bridge. Targeting the severe cable vibration problem, in addition to using the existing Magnetorheological (MR) damper, the current study proposes a new type of damper, called the Tuned Mass Damper-Magnetorheological (TMD-MR) damper. Theoretical and experimental investigations for the damper performance on the cable vibration reduction are conducted, which provides the necessary research support for practical implementation. Experiments on the individual MR damper are carried out first to gain some experience on the …

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Filippov's Operator And Discontinuous Differential Equations, Khalid Abdulaziz Alshammari Jan 2006

Filippov's Operator And Discontinuous Differential Equations, Khalid Abdulaziz Alshammari

LSU Doctoral Dissertations

The thesis is mainly concerned about properties of the so-called Filippov operator that is associated with a differential inclusion x'(t) ε F(x(t)) a.e. t ε [0,T], where F : Rn → Rn is given set-valued map. The operator F produces a new set-valued map F[F], which in effect regularizes F so that F[F] has nicer properties. After presenting its definition, we show that F[F] is always upper-semicontinuous as a map from Rn to the metric space of compact subsets of Rn endowed with the Hausdorff metric. Our main approach is to study the …

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Computation Of Bit-Error Probabilities For Optical Receivers Using Thin Avalanche Photodiodes, Byonghyok Choi, Majeed M. Hayat Jan 2006

Computation Of Bit-Error Probabilities For Optical Receivers Using Thin Avalanche Photodiodes, Byonghyok Choi, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

The large-deviation-based asymptotic-analysis and importance-sampling methods for computing bit-error probabilities for avalanche-photodiode (APD) based optical receivers, developed by Letaief and Sadowsky [IEEE Trans. Inform. Theory, vol. 38, pp. 1162-1169, 1992], are extended to include the effect of dead space, which is significant in high-speed APDs with thin multiplication regions. It is shown that the receiver's bit-error probability is reduced as the magnitude of dead space increases relative to the APD's multiplication-region width. The calculated error probabilities and receiver sensitivities are also compared with those obtained from the Chernoff bound.

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Design And Evaluation Of Automated, Continuous Culture Techniques For Brachionus Rotundiformis, Zhengzhong Zhang Jan 2006

Design And Evaluation Of Automated, Continuous Culture Techniques For Brachionus Rotundiformis, Zhengzhong Zhang

LSU Doctoral Dissertations

A 40-L recirculating rotifer turbidostat (RRT) pilot system consisting of a rotifer reactor, biofilter, foam fractionator, feed container, harvester, and two air-lift pumps was designed to produce B. rotundiformis, a small (S-type) rotifer, that is increasingly demanded for production of small-gape marine finfish larvae. The system’s automatic monitoring (turbidity, pH, conductivity and temperature) and controlling (turbidity, pH, feeding and harvesting) were performed by a Rugid™ computer. A 4 (temperature) x 3 (salinity) study indicated that a 30oC/15 ppt treatment is the most favorable to the growth of B. rotundiformis. Under these conditions, the effect of harvest rate on rotifer system …

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Multi-Model Kalman Filtering For Adaptive Nonuniformity: Correction In Infrared Sensors, Jorge E. Pezoa, Majeed M. Hayat, Sergio N. Torres, Md. Saifur Rahman Jan 2006

Multi-Model Kalman Filtering For Adaptive Nonuniformity: Correction In Infrared Sensors, Jorge E. Pezoa, Majeed M. Hayat, Sergio N. Torres, Md. Saifur Rahman

Electrical and Computer Engineering Faculty Research and Publications

This paper presents an adaptive technique for the estimation of nonuniformity parameters of infrared focal-plane arrays that is robust with respect to changes and uncertainties in scene and sensor characteristics. The proposed algorithm is based on using a bank of Kalman filters in parallel. Each filter independently estimates state variables comprising the gain and the bias matrices of the sensor, according to its own dynamical-model parameters, which underly the statistics of the scene and the nonuniformity as well as the temporal drift in the nonuniformity. The supervising component of the algorithm then generates the final estimates of the state variables …

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Integrated Circuit Metrology By Multilevel Patterning Technology, Li Jiang Jan 2006

Integrated Circuit Metrology By Multilevel Patterning Technology, Li Jiang

LSU Doctoral Dissertations

A low cost, high accuracy method is described in detail for measuring image placement in integrated circuit manufacture. The method measures both the overlay between levels and the absolute placement of features in a single level. The overlay is measured by a technique which views multiple levels separately. The absolute distances between features on a test wafer are measured by comparing the features to precision gratings. Optical imaging techniques are described for viewing and analyzing the grating images, as well as for measuring distortions in the observing microscope and a video camera. These techniques permit image placement measurements to be …

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Active Control Of Spray Combustion, Onur Tuncer Jan 2006

Active Control Of Spray Combustion, Onur Tuncer

LSU Doctoral Dissertations

Effect of a forced dilution air jet on air-fuel spray mixing and emissions has been investigated. Temperature measurements have been made at a number of forcing frequencies in the range of 100-1100 Hz and blowing ratios between 6-15. Open-loop flame response to forcing has also been acquired by recording pressure and heat release spectra. The results show that the mean temperature field inside the flame can be altered due to jet modulation. Significant effects are observed by forcing at locations close to the dump plane. Enhancements in temperature of the order of 100–200 ˚C, and reduction in pattern factor of …

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A State-Space Approach To Blind Estimation Of Mimo Wireless Channels, Hesham Mahmoud Zarif Amin Badr Jan 2006

A State-Space Approach To Blind Estimation Of Mimo Wireless Channels, Hesham Mahmoud Zarif Amin Badr

LSU Doctoral Dissertations

This dissertation focuses on blind channel estimation in wireless communications such that the estimated channel admits the minimum phase property. It assumes only the second order statistics of the transmitted signal at the receive side. Our proposed approach is based on the generalized spectral factorization because of the deficient normal rank for the power spectral density (PSD) function of the received signal. We will show the relationship between the generalized spectral factorization and inner-outer factorizations where the inner is square with smaller size. The inner-outer factorization is in turn related to the generalized Kalman filtering in which the dimension of …

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Tribological Aspects Of Journal Bearings Focusing On The Stribeck Curve, Xiaobin Lu Jan 2006

Tribological Aspects Of Journal Bearings Focusing On The Stribeck Curve, Xiaobin Lu

LSU Doctoral Dissertations

The dissertation focuses on the frictional characteristics of journal bearings as represented by the Stribeck curve. The behavior of lift-off speed and the factors that affect it are explored. An equation is proposed for predicting the lift-off speed. The comparison between the experimental results of oil- and grease-lubricated journal bearings with a mixed elastohydrodynamic lubrication model for line contacts is indicative of good agreement in the mixed lubrication regime. Efforts are made to modify the surface profile of bushing by putting dimples on its surface. Experimental results show that with proper dimensions of dimples, the friction performance of journal bearings …

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Mimo-Ofdm Communication Systems: Channel Estimation And Wireless Location, Zhongshan Wu Jan 2006

Mimo-Ofdm Communication Systems: Channel Estimation And Wireless Location, Zhongshan Wu

LSU Doctoral Dissertations

In this new information age, high data rate and strong reliability features our wireless communication systems and is becoming the dominant factor for a successful deployment of commercial networks. MIMO-OFDM (multiple input multiple output-orthogonal frequency division multiplexing), a new wireless broadband technology, has gained great popularity for its capability of high rate transmission and its robustness against multi-path fading and other channel impairments. A major challenge to MIMO-OFDM systems is how to obtain the channel state information accurately and promptly for coherent detection of information symbols and channel synchronization. In the first part, this dissertation formulates the channel estimation problem …

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Influence Of Surface Chemistry On The Aggregation Of Beta Amyloid Peptide, Mariah Joan Wooldridge Mcmasters Jan 2006

Influence Of Surface Chemistry On The Aggregation Of Beta Amyloid Peptide, Mariah Joan Wooldridge Mcmasters

LSU Doctoral Dissertations

Alzheimer's disease is a progressive neurological ailment affecting 4.5 million aging Americans. The disease is characterized by the presence in the brain of self-assembled fibrils consisting of beta amyloid protein (Aβ). Soluble Aβ protein is present in normal human cerebrospinal fluid, but it is unclear what makes the protein aggregate into insoluble plaques. There is evidence that the Aβ fibril assembly is affected by interactions with biological surfaces, such as neuronal membranes. Here, surfaces consisting of self-assembled alkanethiol monolayers with different end groups were used to test the effect of surface chemistry on the structure and morphology of aggregates formed …

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A Distribution Kinetics Approach For Polymer Crystallization And Phase Separation, Jiao Yang Jan 2006

A Distribution Kinetics Approach For Polymer Crystallization And Phase Separation, Jiao Yang

LSU Doctoral Dissertations

The mechanism of polymer crystallization is extensively studied and still far away from consensus. This research adopted cluster size distribution kinetics approach to explore the kinetics of polymer crystallization and phase separation within spinodal region. The kinetics of polymer crystallization is studied by integrating nucleation, crystal growth and ripening. Population balance equations based on crystal size distribution and concentration of amorphous polymer segments are solved numerically and the related differential moment equations are also solved. The model accounts for nucleation and crystal growth. Different mass dependences of growth and dissociation rate coefficients are proposed to investigate the fundamental features of …

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Cardio-Respiratory Interaction And Its Contribution In Syncope, Xue Wang Jan 2006

Cardio-Respiratory Interaction And Its Contribution In Syncope, Xue Wang

University of Kentucky Doctoral Dissertations

A hypothetical causal link between ventilatory regulation of carbon dioxide anddevelopment of syncope during orthostatic challenges is reduction in arterial partialpressure of carbon dioxide and resultant reduction in cerebral blood flow. We performedtwo experiments to investigate the ventilatory sensitivity to carbon dioxide and factorsaffecting cerebral autoregulation (CA). We also studied the nonlinear phase couplingbetween cardio-respiratory parameters before syncope.For experiment one, in 30 healthy adults, we stimulated chemo and baro reflexesby breathing either room-air or room-air with 5 percent carbon dioxide in a pseudorandom binary sequence during supine and 70 degree head up tilt (HUT). Six subjectsdeveloped presyncope during tilt.To determine …

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Investigations Into The Cognitive Abilities Of Alternate Learning Classifier System Architectures, David Alexander Gaines Jan 2006

Investigations Into The Cognitive Abilities Of Alternate Learning Classifier System Architectures, David Alexander Gaines

University of Kentucky Doctoral Dissertations

The Learning Classifier System (LCS) and its descendant, XCS, are promising paradigms for machine learning design and implementation. Whereas LCS allows classifier payoff predictions to guide system performance, XCS focuses on payoff-prediction accuracy instead, allowing it to evolve "optimal" classifier sets in particular applications requiring rational thought. This research examines LCS and XCS performance in artificial situations with broad social/commercial parallels, created using the non-Markov Iterated Prisoner's Dilemma (IPD) game-playing scenario, where the setting is sometimes asymmetric and where irrationality sometimes pays. This research systematically perturbs a "conventional" IPD-playing LCS-based agent until it results in a full-fledged XCS-based agent, contrasting …

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Dynamics Of Action Potential Duration: Effects On Restitution And Repolarization Alternans, Runze Wu Jan 2006

Dynamics Of Action Potential Duration: Effects On Restitution And Repolarization Alternans, Runze Wu

University of Kentucky Doctoral Dissertations

The presented studies investigate dynamics of action potential duration (APD) tobetter understand the underlying mechanism for repolarization alternans.We recorded trans-membrane potentials (TMP) in canine endocardial muscle tissueusing standard glass microelectrode under the control of an explicit diastolic interval (DI)control pacing protocol, i.e. feedback protocol. During sequential sinusoidal DI activation,the trajectory of APD dynamics has multiple values of APD correspondent to the sameDI, i.e. restitution is a bi-modal relationship. Our results indicate that: 1) there is a delay,similar to hysteresis, of change in APD responding to change in DI, 2) and the timecourse of the delay is asymmetric for fast or …

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Oxidative Stress And Redox Proteomics Studies In Models Of Neurodegenerative Disorders: I. The Canine Model Of Human Aging; Ii. Insights Into Successful Aging; And Iii. Traumatic Brain Injury, Wycliffe Omondi Opii Jan 2006

Oxidative Stress And Redox Proteomics Studies In Models Of Neurodegenerative Disorders: I. The Canine Model Of Human Aging; Ii. Insights Into Successful Aging; And Iii. Traumatic Brain Injury, Wycliffe Omondi Opii

University of Kentucky Doctoral Dissertations

The studies presented in this dissertation were conducted with the objective ofgaining greater understanding into the mechanisms of successful aging, the role ofmitochondria dysfunction in traumatic brain injury, and also on the mechanisms ofimproved learning and cognitive function in the aging.Aging is usually characterized by impairments in physiological functionsincreasing its susceptibility to dementia and neurodegenerative disorders. In thisdissertation, the mechanisms of dementia-free aging were investigated. The use of anantioxidant fortified diet and a program of behavioral enrichment in the canine model ofhuman aging was shown to result in a significant decrease in the levels of oxidativestress. A proteomic analysis of …

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Dynamic Freeway Travel Time Prediction Using Single Loop Detector And Incident Data, Jingxin Xia Jan 2006

Dynamic Freeway Travel Time Prediction Using Single Loop Detector And Incident Data, Jingxin Xia

University of Kentucky Doctoral Dissertations

The accurate estimation of travel time is valuable for a variety of transportation applications such as freeway performance evaluation and real-time traveler information. Given the extensive availability of traffic data collected by intelligent transportation systems, a variety of travel time estimation methods have been developed. Despite limited success under light traffic conditions, traditional corridor travel time prediction methods have suffered various drawbacks. First, most of these methods are developed based on data generated by dual-loop detectors that contain average spot speeds. However, single-loop detectors (and other devices that emulate its operation) are the most commonly used devices in traffic monitoring …

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Analysis, Design, And Laboratory Evaluation Of A Distributed Unified Power Flow Controller Concept, Qiang Li Jan 2006

Analysis, Design, And Laboratory Evaluation Of A Distributed Unified Power Flow Controller Concept, Qiang Li

University of Kentucky Doctoral Dissertations

A single-phase, buck-boost based, dual-output AC-DC converter is studied in this thesis. The converter has two DC outputs with opposite polarities, which share the same ground with the input power line. The power stage performance, including the input filter, is studied and procedure to select power components is given. The circuit model is analyzed to develop appropriate control. Zerocrossing distortion of the source input current is addressed and a solution is proposed. Experimental results are satisfactory in that a high power factor line current results for steady-state operation.

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Thermal Heat Transport At The Nano-Scale Level And Its Application To Nano-Machining, Basil T. Wong Jan 2006

Thermal Heat Transport At The Nano-Scale Level And Its Application To Nano-Machining, Basil T. Wong

University of Kentucky Doctoral Dissertations

Nano-manufacturing is receiving significant attention in industry due to the ever-growing interest in nanotechnology in research institutions. It is hypothesized that single-step or direct-write nano-scale machining might be achieved by coupling nano-probe field emission with radiation transfer. A laser may be used to heat a workpiece within a microscopic region that encloses an even smaller nanoscopic region subjected to a focused electron beam. The electron-beam supplies marginal heat sufficient to remove a minute volume of material by evaporation or sublimation. Experimentally investigating this hypothesis requires an estimate of the power needed in the electron-beam. To this end, a detailed numerical …

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A Numerical Study Of A New Spray Applicator, Vedanth Srinivasan Jan 2006

A Numerical Study Of A New Spray Applicator, Vedanth Srinivasan

University of Kentucky Doctoral Dissertations

This study focuses on the design and development of a new spray applicator design utilizing effects of imposed pressure oscillations in conjunction with cavitation collapse energy to create distribution of fine droplets. An oscillating horn placed inside the nozzle performing high frequency oscillations is envisioned to provide the necessary pressure perturbations on the exiting liquid jet, while the nozzle geometry design in configured to amplify cavitation process. Initially, a two-zone approach modeling the nozzle interior and exterior in a separate fashion and later, a coupled strategy is proposed. Parametric studies describing the effect of horn stroke length, frequency, its position …

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Deeper Groundwater Flow And Chemistry In The Arsenic Affected Western Bengal Basin, West Bengal, India, Abhijit Mukherjee Jan 2006

Deeper Groundwater Flow And Chemistry In The Arsenic Affected Western Bengal Basin, West Bengal, India, Abhijit Mukherjee

University of Kentucky Doctoral Dissertations

Natural attenuation of trichloroethene (TCE) and technetium (99Tc) was studied for five consecutive seasons (from January 2002 to January 2003) in Little Bayou Creek. The stream receives ground water discharge from an aquifer contaminated by past waste disposal activities at the Paducah Gaseous Diffusion Plant (PGDP), a uranium enrichment facility near Paducah, Kentucky. Results from stream gaging, contaminant monitoring, tracer tests (with bromide, nitrate, rhodamine WT and propane) and simulation modeling indicate the TCE is naturally attenuated by volatilization and dilution, with volatilization rates related to the ambient temperature and surface discharge rate. The only apparent mechanism of 99Tc attenuation …

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