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Doctoral Dissertations

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Holomorphic Extensions In Toric Varieties, Malgorzata Aneta Marciniak Jan 2009

Holomorphic Extensions In Toric Varieties, Malgorzata Aneta Marciniak

Doctoral Dissertations

"The dissertation describes the Hartogs and the Hartogs-Bochner extension phenomena in smooth toric varieties and their connection with the first cohomology group with compact support and sheaf coefficients. The affirmative and negative results are proved for toric surfaces and for line bundles over toric varieties using topological, analytic, and algebraic methods"--Abstract, page iii.


Crustal Modification By Tectonic Events And Upper Mantle Anisotropy Beneath The Midcontinent Rift And New Madrid Seismic Zone: Insights From Receiver Function Studies And Teleseismic Shear Wave Splitting, Moikwathai Moidaki Jan 2009

Crustal Modification By Tectonic Events And Upper Mantle Anisotropy Beneath The Midcontinent Rift And New Madrid Seismic Zone: Insights From Receiver Function Studies And Teleseismic Shear Wave Splitting, Moikwathai Moidaki

Doctoral Dissertations

"The earth's crust and upper mantle have been continually modified by tectonic processes such as rifting, earthquake activity. In this dissertation, shear wave splitting and receiver function techniques were employed to study the extent of crustal and upper mantle modifications beneath the New Madrid Seismic Zone (NMSZ) and the Midcontinent Rift (MCR). Shear wave splitting analysis in the MCR reveals the presence of fossilised anisotropy along the rift axis...In the NMSZ, anticipated rift-parallel fast directions associated with vertical magmatic dikes or along-rift flow, rift-orthogonal fast directions from small-scale convection, or reduction in splitting times as a result of vertical asthenospheric …


Emi Failure Analysis Techniques And Noise Prediction For Trace Crossing Split Planes, Weifeng Pan Jan 2009

Emi Failure Analysis Techniques And Noise Prediction For Trace Crossing Split Planes, Weifeng Pan

Doctoral Dissertations

"A variety of methods exist that help locate the source, coupling path, and antenna in an electromagnetic interference (EMI) problem. No single method is the best option in all cases. A good electromagnetic compatibility (EMC) engineer should understand and have experience with a wide range of failure analysis methods and thus, be able to select the most appropriate ones for a given problem. The first three papers are from a series of articles, which explains a set of methods for the analysis of EMI failures. Each method is categorized based on two criteria: 1) the elements in an EMI problem …


Investigation Of The Interactions Between Selected Nanoparticles And Human Lung Carcinoma Cells At The Single Cell And Single Particle Level, Isaac Stayton Jan 2009

Investigation Of The Interactions Between Selected Nanoparticles And Human Lung Carcinoma Cells At The Single Cell And Single Particle Level, Isaac Stayton

Doctoral Dissertations

"The recent advances in nanomaterials development and applications have sparked concerns regarding the safety of these materials in living organisms. This body of work investigates specific interactions between chosen nanoparticles and living human lung carcinoma (A549) cells"--Abstract, page iv.


Helical Force Flow: A New Engineering Mechanics Model For Biological Materials, Jeffery S. Thomas Jan 2009

Helical Force Flow: A New Engineering Mechanics Model For Biological Materials, Jeffery S. Thomas

Doctoral Dissertations

"The author has long speculated that the prevalence of helical structures in botany and zoology hints to an optimized pathway for force and/or energy transfer. His goal has been to realize an alternative approach to the standard stress analysis used in engineering in order to more efficiently and accurately deal with biological materials. Improved tools for these natural materials should in turn aid the design and analysis of engineered materials. Following the role of a navigator in leaf C. Levesque's book "Breakthrough Creativity", the author typically searches for ideas in a variety of places, including physics, materials science, biomimetics, dimensional …


An Experimental And Numerical Investigation Of Flapping And Plunging Wings, Taylor A. Swanson Jan 2009

An Experimental And Numerical Investigation Of Flapping And Plunging Wings, Taylor A. Swanson

Doctoral Dissertations

"Micro air vehicles, or MAVs, are of current interest for a multitude of uses to which they, being small, unmanned vehicles, are uniquely suited. Among the proposed uses are exploration, reconnaissance, and communications. They can be deployed inside buildings, where their small size, hovering capability, and maneuverability, are important factors. Due to their small size, they operate at low Reynolds numbers where conventional flying mechanisms are not advantageous. Thus, attempts have been made to learn from natural flyers like insects and birds. Natural flight is accomplished by flapping wings, and this idea has been proposed for certain types of MAVs …


A Control-Theoretical Fault Prognostics And Accommodation Framework For A Class Of Nonlinear Discrete-Time Systems, Balaje T. Thumati Jan 2009

A Control-Theoretical Fault Prognostics And Accommodation Framework For A Class Of Nonlinear Discrete-Time Systems, Balaje T. Thumati

Doctoral Dissertations

"Fault diagnostics and prognostics schemes (FDP) are necessary for complex industrial systems to prevent unscheduled downtime resulting from component failures. Existing schemes in continuous-time are useful for diagnosing complex industrial systems and no work has been done for prognostics. Therefore, in this dissertation, a systematic design methodology for model-based fault prognostics and accommodation is undertaken for a class of nonlinear discrete-time systems. This design methodology, which does not require any failure data, is introduced in six papers. In Paper I, a fault detection and prediction (FDP) scheme is developed for a class of nonlinear system with state faults by assuming …


Analysis Using Surface Wave Methods To Detect Shallow Manmade Tunnels, Niklas Henry Putnam Jan 2009

Analysis Using Surface Wave Methods To Detect Shallow Manmade Tunnels, Niklas Henry Putnam

Doctoral Dissertations

"Multi-method seismic surface wave approach was used to locate and estimate the dimensions of shallow horizontally-oriented cylindrical voids or manmade tunnels. The primary analytical methods employed were Attenuation Analysis of Rayleigh Waves (AARW), Surface Wave Common Offset (SWCO), and Spiking Filter (SF). Surface wave data were acquired at six study sites using a towed 24-channel land streamer and elastic-band accelerated weight-drop seismic source. Each site was underlain by one tunnel, nominally 1 meter in diameter and depth. The acquired surface wave data were analyzed automatically. Then interpretations compared to the field measurements to ascertain the degree of accuracy. The purpose …


Decentralized Adaptive Neural Network Control Of Interconnected Nonlinear Dynamical Systems With Application To Power System, Shahab Mehraeen Jan 2009

Decentralized Adaptive Neural Network Control Of Interconnected Nonlinear Dynamical Systems With Application To Power System, Shahab Mehraeen

Doctoral Dissertations

"Traditional nonlinear techniques cannot be directly applicable to control large scale interconnected nonlinear dynamic systems due their sheer size and unavailability of system dynamics. Therefore, in this dissertation, the decentralized adaptive neural network (NN) control of a class of nonlinear interconnected dynamic systems is introduced and its application to power systems is presented in the form of six papers. In the first paper, a new nonlinear dynamical representation in the form of a large scale interconnected system for a power network free of algebraic equations with multiple UPFCs as nonlinear controllers is presented. Then, oscillation damping for UPFCs using adaptive …


Fully Differential Cross Sections For Four-Body Scattering Processes, Allison L. Harris Jan 2009

Fully Differential Cross Sections For Four-Body Scattering Processes, Allison L. Harris

Doctoral Dissertations

"While the original concept of the atom can be traced back to the ancient Greeks, current knowledge of the atom is due largely to the study of atomic collisions. The structure of atoms is now fairly well understood, but the understanding of their interactions remains incomplete. In atomic collisions, the particles involved in the collision interact through the Coulomb force, which is known exactly. However, for Coulomb forces, the solution of the Schrödinger equation can only be obtained analytically for two mutually interacting particles. As a result, when more than two particles are involved, theory must resort to approximations. The …


Hydrogen Infrastructure: Resource Evaluation And Capacity Modeling, Kevin B. Martin Jan 2009

Hydrogen Infrastructure: Resource Evaluation And Capacity Modeling, Kevin B. Martin

Doctoral Dissertations

"A hydrogen economy could offer energy stability, economical, and environmental benefits. Several issues are involved in the design and implementation of a hydrogen economy such as the selection of feedstocks, generation and storage technologies, transportation methods, appropriate equipment capacity, codes/standards and public awareness. The design of a hydrogen infrastructure may seem insurmountable; however, as the system is deconstructed a proper design can be achieved. In order to better understand how a hydrogen system for light duty vehicles might operate, both hydrogen resource and capacity analysis and modeling is conducted. Specifically, an evaluation of leading near term production and distribution technologies …


The Cretaceous-Paleogene Transition In The Northern Mississippi Embayment, S.E. Missouri: Palynology, Micropaleontology, And Evidence Of A Mega-Tsunami Deposit, Tambra L. Eifert Jan 2009

The Cretaceous-Paleogene Transition In The Northern Mississippi Embayment, S.E. Missouri: Palynology, Micropaleontology, And Evidence Of A Mega-Tsunami Deposit, Tambra L. Eifert

Doctoral Dissertations

"Upper Cretaceous to lower Paleogene sedimentary rocks in Southeastern Missouri record the northwest extension of the Mississippi Embayment, yet very little information exists about them due to lack of exposures. Access to borehole and trench material and well logs provided an opportunity to study the sedimentology, palynology and micropaleontology of the three formations spanning the Cretaceous-Paleogene (K-Pg) boundary interval: Owl Creek (Cretaceous) and Clayton and Porters Creek (Paleocene). Lithologic features, palynomorphs (mainly spores, pollen, dinoflagellate cysts), dispersed organic matter, and foraminifera were used to interpret biostratigraphy, paleovegetation, paleoclimatic and depositional conditions, thereby creating a framework upon which further questions involving …


The Kalman Filter On Time Scales, Nicholas J. Wintz Jan 2009

The Kalman Filter On Time Scales, Nicholas J. Wintz

Doctoral Dissertations

"In this work, we study concepts in optimal control for dynamic equations on time scales, which unfies the discrete and continuous cases. After a brief introduction of dynamic equations on time scales, we will examine controllability and observability for linear systems. Then we construct and solve the linear quadratic regulator for arbitrary time scales. Here, we seek to find an optimal control that minimizes a given cost function associated with a linear system. We will find such an input under two different settings; when the final state is fixed and when it is free. Later, we extend these results to …


Electrodeposition Of Inorganic Materials With Tailored Shapes And Chiral Morphologies, Elizabeth A. Kulp Jan 2009

Electrodeposition Of Inorganic Materials With Tailored Shapes And Chiral Morphologies, Elizabeth A. Kulp

Doctoral Dissertations

"This dissertation investigates the electrodeposition of metal oxide films and biomaterial deposits on polycrystalline and single crystal substrates. Paper I describes the mechanisms and the characterization of an electrodeposited polycrystalline insulator, ceria (CeO₂), on Hastelloy substrates produced by the electrochemical oxidation of Ce(III) acetate complexes. In Paper II, epitaxial films of magnetite (Fe₃O₄) and ferrihydrite (Fe₁₀O₁₄(OH)₂) are deposited on gold single crystals. Paper III reports the electrodeposition of epitaxial Fe₃O₄ and zinc ferrite (ZnFe₂O₄) periodic nanostructures known as superlattices by pulsing between two potentials. Papers IV and V describe chiral electrodeposition. In Paper IV, epitaxial, chiral orientations of cupric oxide …


Rational Construction By Molecular Dynamics Modeling And Simulations Of Porous Adsorbent Media For Bioseparation, Enrico Riccardi Jan 2009

Rational Construction By Molecular Dynamics Modeling And Simulations Of Porous Adsorbent Media For Bioseparation, Enrico Riccardi

Doctoral Dissertations

"Ion-exchange chromatography employing porous adsorbent particles or monoliths in which charged ligands are immobilized onto polymeric extender molecules grafted on the pore surfaces of a base matrix has become a very important method for bioseparations. In this dissertation, a novel fundamental and systematic methodology has been developed that uses the molecular dynamics (MD) modeling and simulation approach to rationally design, construct, and characterize polymeric porous adsorbent media and study the transport and adsorption of a charged biomolecule (desmopressin) in a representative adsorbent medium. The MD results have also been utilized in a macroscopic model to study the large-scale dynamic behavior …


Administration Practices Of Physical Education Teachers For The California Physical Fitness Test, Susan Lynn Eastham Jan 2009

Administration Practices Of Physical Education Teachers For The California Physical Fitness Test, Susan Lynn Eastham

Doctoral Dissertations

unavailable


High School English Language Arts Teachers' Conceptualizations Of Pedagogical Content Knowledge, Donna Hyatt Scarlett Jan 2009

High School English Language Arts Teachers' Conceptualizations Of Pedagogical Content Knowledge, Donna Hyatt Scarlett

Doctoral Dissertations

unavailable


How Do Adolescent Students Experience Teacher-Student Interactions In A Seventh Grade Classroom And How Do Those Experiences Affect Their Self-Efficacy Beliefs?, Katherine Sanjiyan Barg Jan 2009

How Do Adolescent Students Experience Teacher-Student Interactions In A Seventh Grade Classroom And How Do Those Experiences Affect Their Self-Efficacy Beliefs?, Katherine Sanjiyan Barg

Doctoral Dissertations

unavailable


On Unified Computational Intelligence: Neural Networks, Dynamic Programming, And Applications To Economics And Finance, John E. Seiffertt Iv Jan 2009

On Unified Computational Intelligence: Neural Networks, Dynamic Programming, And Applications To Economics And Finance, John E. Seiffertt Iv

Doctoral Dissertations

"This dissertation introduces the concept of unified computational intelligence and encompasses algorithm design, applications, theoretical developments, and the identification of new frontiers for multidisciplinary research. It presents a new way to look at unified learning systems and presents a novel Adaptive Resonance Theory-based unified learning architecture. An application to robotic security and sensor fusion is given in detail.

Work on the theoretical developments of unified computational intelligence is also presented. A new theorem in the time scales calculus is proven and theorems on the Hamilton-Jacobi-Ballman equation of dynamic programming and the dynamic programming algorithm are presented, both for various general …


The Organization In Front Of The Text : A Critical Hermeneutic Inquiry In Employee Policy Appropriation, Marisa B. Michaels Jan 2009

The Organization In Front Of The Text : A Critical Hermeneutic Inquiry In Employee Policy Appropriation, Marisa B. Michaels

Doctoral Dissertations

unavailable


Investigating The Impact Of Microbial Interactions With Geologic Media On Geophysical Properties, Caroline A. Davis Jan 2009

Investigating The Impact Of Microbial Interactions With Geologic Media On Geophysical Properties, Caroline A. Davis

Doctoral Dissertations

"The goals of this study were to investigate the effect of: (1) microbial metabolic byproducts, microbial growth, and biofilm formation on the low frequency electrical properties of porous media, (2) biofilm formation on acoustic wave properties, and (3) the natural electrical (self-potential) signatures associated with an in-situ biological permeable reactive barrier (PRB). The results suggest: (1) increases in electrolytic conductivity are consistent with increased concentrations of organic acids and biosurfactants; (2) mineral weathering promoted by organic acids causes increases in electrolytic conductivity, concomitant with increases in major cation concentrations; (3) interfacial conductivity generally parallels microbial cell concentrations and biofilm formation; …


Integrated Mining Of Feature Spaces For Bioinformatics Domain Discovery, Pradeep Chowriappa Oct 2008

Integrated Mining Of Feature Spaces For Bioinformatics Domain Discovery, Pradeep Chowriappa

Doctoral Dissertations

One of the major challenges in the field of bioinformatics is the elucidation of protein folding for the functional annotation of proteins. The factors that govern protein folding include the chemical, physical, and environmental conditions of the protein's surroundings, which can be measured and exploited for computational discovery purposes. These conditions enable the protein to transform from a sequence of amino acids to a globular three-dimensional structure. Information concerning the folded state of a protein has significant potential to explain biochemical pathways and their involvement in disorders and diseases. This information impacts the ways in which genetic diseases are characterized …


A Hyperbolic Two-Step Model Based Finite Difference Method For Studying Thermal Deformation In Three-Dimensional Micro Spheres Exposed To Ultrashort-Pulsed Lasers, Pan Wang Oct 2008

A Hyperbolic Two-Step Model Based Finite Difference Method For Studying Thermal Deformation In Three-Dimensional Micro Spheres Exposed To Ultrashort-Pulsed Lasers, Pan Wang

Doctoral Dissertations

Ultrashort-pulsed lasers with pulse durations of the order of sub-picoseconds to femtoseconds possess the capabilities in limiting the undesirable spread of the thermal process zone in a heated sample. Because of this, ultrashort-pulsed lasers have been attracting worldwide interest in science and engineering. The success of ultrashort-pulsed lasers in real application relies on: (1) well characterized pulse width, intensity and experimental techniques; (2) reliable microscale heat transfer models; and (3) prevention of thermal damage. Laser damage induced by ultrashort-pulsed lasers occurs after the heating pulse is over, since the pulse duration time is extremely short and the heat flux is …


A Finite Difference Method For Studying Thermal Deformation In Three-Dimensional Thin Films Exposed To Ultrashort Pulsed Lasers, Suyang Zhang Jul 2008

A Finite Difference Method For Studying Thermal Deformation In Three-Dimensional Thin Films Exposed To Ultrashort Pulsed Lasers, Suyang Zhang

Doctoral Dissertations

Thermal analysis related to ultrashort-pulsed lasers has been intensely studied in science and engineering communities in recent years, because the pulse duration of ultrashort-pulsed lasers is only the order of sub-picoseconds to femtoseconds, and the lasers have exclusive capabilities in limiting the undesirable spread of the thermal process zone in the heated sample. Studying the thermal deformation induced by ultrashort-pulsed lasers is essential for preventing thermal damage. For the ultrashort-pulsed laser, the thermal damage is different from that caused by the long pulsed lasers and cracks occur after heating.

This dissertation presents a new finite difference method for studying thermal …


A Simulation Of The Neural Action Potential Under The Influence Of Acetylcholinesterase Inhibitors Modeled In The Neuromuscular Junction, Frank Jenkins Jul 2008

A Simulation Of The Neural Action Potential Under The Influence Of Acetylcholinesterase Inhibitors Modeled In The Neuromuscular Junction, Frank Jenkins

Doctoral Dissertations

The rise of terrorism has created an interest in better ways to detect when humans are exposed to neurotoxins, especially nerve gases developed for military use, most of which are acetylcholinesterase inhibitors. Many current methods of detection are based on mass spectrometry, a method that is cumbersome and not particularly robust when used as an early warning method. The detection of acetylcholinesterase inhibitors would benefit from a combined model of the processes occurring in the neuromuscular junction between the presynaptic action potential and the motor end-plate action potential that includes the kinetics of acetylcholine and acetylcholinesterase in the synaptic cleft. …


Poly(Ethylenedioxythiophene) Based Electronic Devices For Sensor Applications, Jie Liu Jul 2008

Poly(Ethylenedioxythiophene) Based Electronic Devices For Sensor Applications, Jie Liu

Doctoral Dissertations

Organic electronic devices, based on Poly (3,4-ethylenedioxythiophene)-Poly (styrene sulfonic acid) (PEDOT-PSS) as the active layer for sensor applications, have been studied. Two sets of sensors have been developed. In one case, sensors consisting of PEDOT-PSS resistors have been realized and demonstrated for soil moisture monitoring. The resistor model for the soil moisture sensor enables the sensor device to be fabricated at low cost and easily tested with a simple structure. Unlike the large dimension device used in Time Domain Reflectometry (TDR), the sensors are small and are capable of capturing microscale behavior of moisture in soil which is useful for …


Failure Analysis And Reliability -Aware Resource Allocation Of Parallel Applications In High Performance Computing Systems, Narasimha Raju Gottumukkala Apr 2008

Failure Analysis And Reliability -Aware Resource Allocation Of Parallel Applications In High Performance Computing Systems, Narasimha Raju Gottumukkala

Doctoral Dissertations

The demand for more computational power to solve complex scientific problems has been driving the physical size of High Performance Computing (HPC) systems to hundreds and thousands of nodes. Uninterrupted execution of large scale parallel applications naturally becomes a major challenge because a single node failure interrupts the entire application, and the reliability of a job completion decreases with increasing the number of nodes. Accurate reliability knowledge of a HPC system enables runtime systems such as resource management and applications to minimize performance loss due to random failures while also providing better Quality Of Service (QOS) for computational users.

This …


Wireless Sensor Network Modeling Using Modified Recurrent Neural Network: Application To Fault Detection, Azzam Issam Moustapha Apr 2008

Wireless Sensor Network Modeling Using Modified Recurrent Neural Network: Application To Fault Detection, Azzam Issam Moustapha

Doctoral Dissertations

Wireless Sensor Networks (WSNs) consist of a large number of sensors, which in turn have their own dynamics. They interact with each other and the base station, which controls the network. In multi-hop wireless sensor networks, information hops from one node to another and finally to the network gateway or base station. Dynamic Recurrent Neural Networks (RNNs) consist of a set of dynamic nodes that provide internal feedback to their own inputs. They can be used to simulate and model dynamic systems such as a network of sensors.

In this dissertation, a dynamic model of wireless sensor networks and its …


K-Means+Id3 And Dependence Tree Methods For Supervised Anomaly Detection, Kiran S. Balagani Apr 2008

K-Means+Id3 And Dependence Tree Methods For Supervised Anomaly Detection, Kiran S. Balagani

Doctoral Dissertations

In this dissertation, we present two novel methods for supervised anomaly detection. The first method "K-Means+ID3" performs supervised anomaly detection by partitioning the training data instances into k clusters using Euclidean distance similarity. Then, on each cluster representing a density region of normal or anomaly instances, an ID3 decision tree is built. The ID3 decision tree on each cluster refines the decision boundaries by learning the subgroups within a cluster. To obtain a final decision on detection, the k-Means and ID3 decision trees are combined using two rules: (1) the nearest neighbor rule; and (2) the nearest consensus rule. The …


Antecedents Of Entrepreneurial Orientation: A Contingency Approach, Laurent Stephane Josien Apr 2008

Antecedents Of Entrepreneurial Orientation: A Contingency Approach, Laurent Stephane Josien

Doctoral Dissertations

This research was created in order to offer a better understanding of the entrepreneurial orientation construct. Based on the literature review several antecedents of the entrepreneurial orientation construct were identified: risk, achievement, innovation, locus of control, self-esteem, opportunity, autonomy, proactiveness, and competitive aggressiveness. Relying on the contingency theory developed by Burns and Stalker (1961), it was decided to use the Carland's trichotomy of entrepreneurs as a moderator variable between the antecedents and the entrepreneurial orientation construct. As a result, three main areas of research were identified. The first area deals with determining which dimensions are underpinning the entrepreneurial orientation construct, …