Physical Sciences and Mathematics | Open Access Articles

Analytic & Numerical Study Of A Vortex Motion Equation, Daniel Bueller

Electronic Theses and Dissertations

A nonlinear second order differential equation related to vortex motion is derived. This equation is analyzed using various numerical and analytical techniques including finding approximate solutions using a perturbative approach.

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Intracavity Laser Absorption Spectroscopy Using Quantum Cascade Laser And Fabry-Perot Interferometer, Gautam Medhi

Electronic Theses and Dissertations

Intracavity Laser Absorption Spectroscopy (ICLAS) at IR wavelengths offers an opportunity for spectral sensing of low vapor pressure compounds. We report here an ICLAS system design based on a quantum cascade laser (QCL) at THz (69.9 m) and IR wavelengths (9.38 and 8.1 m) with an open external cavity. The sensitivity of such a system is potentially very high due to extraordinarily long effective optical paths that can be achieved in an active cavity. Sensitivity estimation by numerical solution of the laser rate equations for the THz QCL ICLAS system is determined. Experimental development of the external cavity QCL is …

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Electromagnetic Propagation Anomalies In Waveguiding Structures And Scattering Systems, Alessandro Salandrino

Electronic Theses and Dissertations

The effects related to diffraction and interference are ubiquitous in phenomena involving electromagnetic wave propagation, and are accurately predicted and described within the framework of classical electrodynamics. In the vast majority of the cases the qualitative features of the evolution of a propagating wave can be inferred even without detailed calculations. A field distribution will spread upon propagation, will accumulate phase along the direction of power flow, will exert mechanical forces upon scattering objects in the direction of propagation etc. When such predictions fail, counterintuitive effects and new functionalities can be engineered. In this work a series of exceptional cases …

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Photo Retro Diels-Alder Reaction Of The Adducts Of Tetracyanoethylene And Polyaromatic Compounds, Siddthartha Banerjee

Electronic Theses and Dissertations

Thermally induced retro-Diels Alder (rDA) reaction has been extensively used for the preparation of many reactive intermediates in organic synthesis. But the uses of photo-retro Diels-Alder (PrDA) reaction in organic synthesis were sparingly reported in literature. Due to its spatial and temporal control, PrDA can be used in making of photosensitive materials, in drug delivery and also for mechanistic studies. Diels-Alder adducts of tetracyanoethylene (TCNE) and polyaromatic compounds (anthracene, napthacene, pentacene and phencyclone) were synthesized and were subjected to PrDA reaction through 254-nm irradiation. The quantum yield and the consequent photoreactivity of these DA adducts follow the following order. TCNE/naphthacene …

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The Study Of Three Different Layered Structures As Model Systems For Hydrogen Storage Materials, Muzaffer Tonguç Öztek

Electronic Theses and Dissertations

The strength and success of the hydrogen economy relies heavily on the storage of hydrogen. Storage systems in which hydrogen is sequestered in a solid material have been shown to be advantageous over storage of hydrogen as a liquid or compressed gas. Many different types of materials have been investigated, yet the desired capacity and uptake/release characteristics required for implementation have not been reached. In this work, porphyrin aggregates were investigated as a new type of material for hydrogen storage. The building blocks of the aggregates are porphyrin molecules that are planar and can assume a face to face arrangement …

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The Extended Kalman-Consensus Filter, Andrew Pellett

Electronic Theses and Dissertations

An algorithm called the extended Kalman-Consensus filter is developed as an extension of the Kalman-Consensus filter to the non-linear case. The extended Kalman- Consensus filter is a technique for estimating the state of a non-linear process disturbed by noise using multiple observations from a distributed set of sense nodes. All sense nodes attempt to estimate the same state by determining how their observations affect that state, and by communicating with neighbor nodes. The algorithm is designed to be more accurate through measurement diversity, scalable to a large number of nodes, and robust against loss of nodes during operation. Simulations are …

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An Evaluation Study Of The Effectiveness Of Using A Reaction-Based Process For Hydrazine Waste Remediation, Cristina M. Oropeza

Electronic Theses and Dissertations

Hydrazine (HZ) and monomethylhydrazine (MMH) are used extensively as hypergolic propellants at Kennedy Space Center. These highly reactive fuels are considered highly toxic, and potentially carcinogenic. Consequently, the transport, handling, and disposal of hydrazines is strictly regulated to protect personnel and the environment. Currently, KSC generates large volumes of hydrazine-laden wastewater for disposal. This waste is contained and shipped on public highways for subsequent disposal by incineration presenting a potentially catastrophic threat to the environment and the general public in the event of an accidental release. Other existing remediation methods include oxidative and reductive pathways as well as biodegradation in …

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Population Viability Analysis Of Swift Fox (Vulpes Velox) At The Badlands National Park, Indrani Sasmal

Electronic Theses and Dissertations

The swift fox (Vulpes velox) was historically distributed in southwestern South Dakota including the region surrounding Badlands National Park (BNP). The species declined during the mid-1900s due to habitat fragmentation, non-target poisoning, and harvest. A remnant population occurred on USDA Forest Service lands in Fall River County, South Dakota. Following the successful reintroduction of the species in Canada (1983), a reintroduction program was initiated in BNP in the year 2003. Free-ranging swift fox from Colorado and Wyoming were translocated to BNP from 2003 to 2006. Despite these releases and observations of free-ranging swift fox occurring throughout western South Dakota, it …

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Effective Task Transfer Through Indirect Encoding, Phillip Verbancsics

Electronic Theses and Dissertations

An important goal for machine learning is to transfer knowledge between tasks. For example, learning to play RoboCup Keepaway should contribute to learning the full game of RoboCup soccer. Often approaches to task transfer focus on transforming the original representation to fit the new task. Such representational transformations are necessary because the target task often requires new state information that was not included in the original representation. In RoboCup Keepaway, changing from the 3 vs. 2 variant of the task to 4 vs. 3 adds state information for each of the new players. In contrast, this dissertation explores the idea …

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The Application Of Chemometrics To The Detection And Classification Of Ignitable Liquids In Fire Debris Using The Total Ion Spectrum, Jennifer N. Lewis

Electronic Theses and Dissertations

Current methods in ignitable liquid identification and classification from fire debris rely on pattern recognition of ignitable liquids in total ion chromatograms, extracted ion profiles, and target compound comparisons, as described in American Standards for Testing and Materials E1618-10. The total ion spectra method takes advantage of the reproducibility among sample spectra from the same American Society for Testing and Materials class. It is a method that is independent of the chromatographic conditions that affect retention times of target compounds, thus aiding in the use of computer-based library searching techniques. The total ion spectrum was obtained by summing the ion …

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Prediction Of Survival Of Early Stages Lung Cancer Patients Based On Er Beta Cellular Expressions And Epidemiological Data, Evgeny Martinenko

Electronic Theses and Dissertations

We attempted a mathematical model for expected prognosis of lung cancer patients based on a multivariate analysis of the values of ER-interacting proteins (ERbeta) and a membrane bound, glycosylated phosphoprotein MUC1), and patients clinical data recorded at the time of initial surgery. We demonstrate that, even with the limited sample size available to use, combination of clinical and biochemical data (in particular, associated with ERbeta and MUC1) allows to predict survival of lung cancer patients with about 80% accuracy while prediction on the basis of clinical data only gives about 70% accuracy. The present work can be viewed as a …

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Metal Blacks As Scattering Centers To Increase The Efficiency Of Thin Film Solar Cells, Deep R. Panjwani

Electronic Theses and Dissertations

Metal nano particles are investigated as scattering centers on front surface of thin-film solar cells to improve efficiency. The principle is that scattering, which is enhanced near the plasmon resonance frequency of the particle and depends on particle size, increases the effective optical path length of incident light, leading to more light absorption in active layer of thin film solar cell. The particular types of particles investigated here are known as "metal-black", well known as an IR absorber for bolometric infrared detectors. Gold-black was deposited on commercial thin-film solar cells using a thermal evaporator in a nitrogen ambient at pressures …

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Computationally Efficient Digital Backward Propagation For Fiber Nonlinearity Compensation, Likai Zhu

Electronic Theses and Dissertations

The next generation fiber transmission system is limited by fiber nonlinearity. A distributed nonlinearity compensation method, known as Digital Backward Propagation (DBP), is necessary for effective compensation of the joint effect of dispersion and nonlinearity. However, in order for DBP to be accurate, a large number of steps are usually required for long-haul transmission, resulting in a heavy computational load. In real time DBP implementation, the FIR filters can be used for dispersion compensation and account for most of the computation per step. A method of designing a complementary filter pair is proposed. The individual errors in the frequency response …

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Finding Dud Vertices In Defensive Alliances And Secure Sets Using Computational Tools, George Worley Ii

Electronic Theses and Dissertations

Defensive alliances are a way of using graphs to model the defense of resources (people, buildings, countries, etc.) against attacks where the number of potential attackers against each resource is known. The initial study of defensive alliances focused on questions of minimal defensive alliances in a graph and the minimum possible size of a defensive alliance in a graph, but in order to apply defensive alliances in modeling real-world situations, additional considerations are important. In particular, since each vertex in a defensive alliance represents some real-world object that has a cost associated with remaining in the defensive alliance, it is …

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The Power Of Quantum Walk Insights, Implementation, And Applications, Chen Fu Chiang

Electronic Theses and Dissertations

In this thesis, I investigate quantum walks in quantum computing from three aspects: the insights, the implementation, and the applications. Quantum walks are the quantum analogue of classical random walks. For the insights of quantum walks, I list and explain the required components for quantizing a classical random walk into a quantum walk. The components are, for instance, Markov chains, quantum phase estimation, and quantum spectrum theorem. I then demonstrate how the product of two reflections in the walk operator provides a quadratic speed-up, in comparison to the classical counterpart. For the implementation of quantum walks, I show the construction …

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Exploring Confidence Intervals In The Case Of Binomial And Hypergeometric Distributions, Irene Mojica

Electronic Theses and Dissertations

The objective of this thesis is to examine one of the most fundamental and yet important methodologies used in statistical practice, interval estimation of the probability of success in a binomial distribution. The textbook confidence interval for this problem is known as the Wald interval as it comes from the Wald large sample test for the binomial case. It is generally acknowledged that the actual coverage probability of the standard interval is poor for values of p near 0 or 1. Moreover, recently it has been documented that the coverage properties of the standard interval can be inconsistent even if …

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Investigation Of Nanoceria-Modified Platinum-Gold Composite Electrodes For The Electrochemical Reduction Of Oxygen In Alkaline Media, Rahul Hegishte

Electronic Theses and Dissertations

Platinum-gold and nanoceria-modified platinum-gold electrodes were prepared on a platinum surface via electrochemical reduction of solutions of platinum and gold salts in the dispersion of nanoceria. The molar ratios of Pt and Au were varied in both PtAu and PtAu/CeO₂ electrodes while the total concentration of the metals was maintained at 2 x 10⁻³M and the concentration of nanoceria was maintained constant at 5 x 10⁻³M. The electrodes were characterized by their cyclic voltammetry curves in 0.5M sulfuric acid solution. The electrochemically active area of the electrodes was determined using the copper underpotential deposition method. The linear sweep voltammograms of …

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Low Noise, Narrow Optical Linewidth Semiconductor-Based Optical Comb Source And Low Noise Rf Signal Generation, Ibrahim Tuna Ozdur

Electronic Theses and Dissertations

Recently optical frequency combs and low noise RF tones are drawing increased attention due to applications in spectroscopy, metrology, arbitrary waveform generation, optical signal processing etc. This thesis focuses on the generation of low noise RF tones and stabilized optical frequency combs. The optical frequency combs are generated by a semiconductor based external cavity mode-locked laser with a high finesse intracavity etalon. In order to get the lowest noise and broadest bandwidth from the mode-locked laser, it is critical to know the free spectral range (FSR) of the etalon precisely. First the etalon FSR is measured by using the modified …

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The Relative Recoverability Of Dna And Rna Profiles From Forensically Relevant Body Fluid Stains, Charly Parker

Electronic Theses and Dissertations

Biological material (fluids or tissues) whether from the victim or suspect is often collected as forensic evidence, and methods to obtain and analyze the DNA found in that material have been well established. The type of body fluid (i.e. blood, saliva, semen, vaginal secretions, and menstrual blood) from which the DNA originated is also of interest, and messenger RNA typing provides a specific and sensitive means of body fluid identification. In order for mRNA profiling to be utilized in routine forensic casework, RNA of sufficient quantity and quality must be obtained from biological fluid stains and the methods used for …

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Infrared Phased-Array Antenna-Coupled Tunnel Diodes, Brian Alan Slovick

Electronic Theses and Dissertations

Infrared (IR) dipole antenna-coupled metal-oxide-metal (MOM) tunnel diodes provide a unique detection mechanism that allows for determination of the polarization and wavelength of an optical field. By integrating the MOM diode into a phased-array antenna, the angle of arrival and degree of coherence of received IR radiation can be determined. The angular response characteristics of IR dipole antennas are determined by boundary conditions imposed by the surrounding dielectric or conductive environment on the radiated fields. To explore the influence of the substrate configuration, single dipole antennas are fabricated on both planar and hemispherical lens substrates. Measurements demonstrate that the angular …

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Low Noise And Low Repetition Rate Semiconductor-Based Mode-Locked Lasers, Dimitrios Mandridis

Electronic Theses and Dissertations

The topic of this dissertation is the development of low repetition rate and low noise semiconductor-based laser sources with a focus on linearly chirped pulse laser sources. In the past decade chirped optical pulses have found a plethora of applications such as photonic analogto-digital conversion, optical coherence tomography, laser ranging, etc. This dissertation analyzes the aforementioned applications of linearly chirped pulses and their technical requirements, as well as the performance of previously demonstrated chirped pulse laser sources. Moreover, the focus is shifted to a specific application of the linearly chirped pulses, timestretched photonic analog-to-digital conversion (TS ADC). The challenges of …

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Convergence Of The Mean Shift Algorithm And Its Generalizations, Ting Hu

Electronic Theses and Dissertations

Mean shift is an effective iterative algorithm widely used in image analysis tasks like tracking, image segmentation, smoothing, filtering, edge detection and etc. It iteratively estimates the modes of the probability function of a set of sample data points based in a region. Mean shift was invented in 1975, but it was not widely used until the work by Cheng in 1995. After that, it becomes popular in computer vision. However the convergence, a key character of any iterative algorithm, has been rigorously proved only very recently, but with strong assumptions. In this thesis, the method of mean shift is …

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Bayesian Model Selection For Classification With Possibly Large Number Of Groups, Justin Kyle Davis

Electronic Theses and Dissertations

The purpose of the present dissertation is to study model selection techniques which are specifically designed for classification of high-dimensional data with a large number of classes. To the best of our knowledge, this problem has never been studied in depth previously. We assume that the number of components p is much larger than the number of samples n, and that only few of those p components are useful for subsequent classification. In what follows, we introduce two Bayesian models which use two different approaches to the problem: one which discards components which have “almost constant” values (Model 1) and …

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Variational Embedded Solitons, And Traveling Wavetrains Generated By Generalized Hopf Bifurcations, In Some Nlpde Systems, Todd Blanton Smith

Electronic Theses and Dissertations

In this Ph.D. thesis, we study regular and embedded solitons and generalized and degenerate Hopf bifurcations. These two areas of work are seperate and independent from each other. First, variational methods are employed to generate families of both regular and embedded solitary wave solutions for a generalized Pochhammer PDE and a generalized microstructure PDE that are currently of great interest. The technique for obtaining the embedded solitons incorporates several recent generalizations of the usual variational technique and is thus topical in itself. One unusual feature of the solitary waves derived here is that we are able to obtain them in …

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Comparing Media Coverage Of The Gulf Oil Spill In The Us And Uk Implications For Global Crisis Communication, Sarah Crytzer

Electronic Theses and Dissertations

The following research is a content analysis of 114 articles written by the American and British news media outlets in the first month following the BP Gulf oil spill in April 2010. The goal of the research was to identify any dominant frames evident in the reports and to compare the two countries to see if there was a difference in the dominant frames used. Positive, negative, and neutral tones were also evaluated to determine if there was a difference between the countries. The results show that both countries reports predominantly used an ecology and action frame, while British media …

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Ray Collection Bounding Volume Hierarchy, Kris Krishna Rivera

Electronic Theses and Dissertations

This thesis presents Ray Collection BVH, an improvement over a current day Ray Tracing acceleration structure to both build and perform the steps necessary to efficiently render dynamic scenes. Bounding Volume Hierarchy (BVH) is a commonly used acceleration structure, which aides in rendering complex scenes in 3D space using Ray Tracing by breaking the scene of triangles into a simple hierarchical structure. The algorithm this thesis explores was developed in an attempt at accelerating the process of both constructing this structure, and also using it to render these complex scenes more efficiently. The idea of using "ray collection" as a …

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Movement Patterns, Survival, And Sightability Of White-Tailed Deer (Odocoileus Virginianus) In Eastern South Dakota, Kevin A. Robling

Electronic Theses and Dissertations

Limited information is available on white-tailed deer (Odocoileus virginianus) movements, survival, density, and resource selection in the Prairie Pothole Region of South Dakota where semi-permanent wetland densities are relatively high. Primary objectives of this study were to develop a sightability model for aerial surveying and document seasonal movement patterns and survival rates for white-tailed deer in this region. Secondary objectives were to calculate seasonal home ranges, daily and seasonal movements relative to management unit boundaries, determine cause specific mortality, and evaluate summer and winter resource use and selection. From February 2009 – February 2010, 43 adult female white-tailed deer along …

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Productivity And Trophic Interactions In The Missouri River Impoundments, Mark J. Fincel

Electronic Theses and Dissertations

Standardized monitoring is a vital component of fisheries assessment in Missouri River impoundments. In South Dakota, annual variation in fish growth and abundance is used to monitor changes in fish populations and develop strategies (i.e. regulations) for managing recreational fishes. Although variation in fish abundance provides important insight into the status of fish populations, it can be difficult to link these changes to environmental conditions (i.e. hydrology) without concurrent information about reservoir productivity. Measures of nutrient concentration, algal biomass, and zooplankton composition/abundance provide important insights into reservoir productivity, but standardized approaches for collecting these measures have not been developed for …

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Crenulation Cleavage Development And The Influence Of Rock Microstructure On Crustal Seismic Anisotropy, Felice Maria Johanna Naus-Thijssen

Electronic Theses and Dissertations

This thesis investigates the cause of mass transfer during crenulation cleavage formation and the role that elastically anisotropic minerals and fabric development play in promoting seismic anisotropy in the crust. Crenulation cleavage is the most common fabric in multiplydeformed, phyllosilicate-rich metamorphic rocks. During its formation the originally planar fabric gets crenulated, eventually leading to the differentiation of quartz- and feldspar-rich regions (QFdomains) in the crenulation hinges, and phyllosilicate-rich regions (P-domains) in the crenulation limbs. This differentiation is driven by the dissolution of quartz and feldspar in the P-domains, and the precipitation of those minerals in the QF-domains. Finite element models …

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Late-Pleistocene Glacial And Climate Fluctuations In The Torres Del Paine Region (51ºs), Southern South America, Juan Luis Garcia

Electronic Theses and Dissertations

Variations in Earth‘s orbital parameters affect insolation and are thought to drive ice-age cycles (Milankovitch Theory). Northern and southern mid-latitudes show opposing insolation signals, because of the effect of precession. Despite this difference, paleoclimate records from both hemispheres display broadly synchronous glacialinterglacial climate changes tied to northern hemisphere insolation. This would imply that southern hemisphere glaciers advanced in the face of increasing local summer insolation during the last glacial maximum and thus raises questions about the orbital theory of ice ages. Well-dated paleoclimate records are important for testing hypotheses concerning the origin of ice ages, particularly in the southern hemisphere. …

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Full-Text Articles in Physical Sciences and Mathematics

Analytic & Numerical Study Of A Vortex Motion Equation, Daniel Bueller

Electronic Theses and Dissertations

Intracavity Laser Absorption Spectroscopy Using Quantum Cascade Laser And Fabry-Perot Interferometer, Gautam Medhi

Electronic Theses and Dissertations

Electromagnetic Propagation Anomalies In Waveguiding Structures And Scattering Systems, Alessandro Salandrino

Electronic Theses and Dissertations

Photo Retro Diels-Alder Reaction Of The Adducts Of Tetracyanoethylene And Polyaromatic Compounds, Siddthartha Banerjee

Electronic Theses and Dissertations

The Study Of Three Different Layered Structures As Model Systems For Hydrogen Storage Materials, Muzaffer Tonguç Öztek

Electronic Theses and Dissertations

The Extended Kalman-Consensus Filter, Andrew Pellett

Electronic Theses and Dissertations

An Evaluation Study Of The Effectiveness Of Using A Reaction-Based Process For Hydrazine Waste Remediation, Cristina M. Oropeza

Electronic Theses and Dissertations

Population Viability Analysis Of Swift Fox (Vulpes Velox) At The Badlands National Park, Indrani Sasmal

Electronic Theses and Dissertations

Effective Task Transfer Through Indirect Encoding, Phillip Verbancsics

Electronic Theses and Dissertations

The Application Of Chemometrics To The Detection And Classification Of Ignitable Liquids In Fire Debris Using The Total Ion Spectrum, Jennifer N. Lewis

Electronic Theses and Dissertations

Prediction Of Survival Of Early Stages Lung Cancer Patients Based On Er Beta Cellular Expressions And Epidemiological Data, Evgeny Martinenko

Electronic Theses and Dissertations

Metal Blacks As Scattering Centers To Increase The Efficiency Of Thin Film Solar Cells, Deep R. Panjwani

Electronic Theses and Dissertations

Computationally Efficient Digital Backward Propagation For Fiber Nonlinearity Compensation, Likai Zhu

Electronic Theses and Dissertations

Finding Dud Vertices In Defensive Alliances And Secure Sets Using Computational Tools, George Worley Ii

Electronic Theses and Dissertations

The Power Of Quantum Walk Insights, Implementation, And Applications, Chen Fu Chiang

Electronic Theses and Dissertations

Exploring Confidence Intervals In The Case Of Binomial And Hypergeometric Distributions, Irene Mojica

Electronic Theses and Dissertations

Investigation Of Nanoceria-Modified Platinum-Gold Composite Electrodes For The Electrochemical Reduction Of Oxygen In Alkaline Media, Rahul Hegishte

Electronic Theses and Dissertations

Low Noise, Narrow Optical Linewidth Semiconductor-Based Optical Comb Source And Low Noise Rf Signal Generation, Ibrahim Tuna Ozdur

Electronic Theses and Dissertations

The Relative Recoverability Of Dna And Rna Profiles From Forensically Relevant Body Fluid Stains, Charly Parker

Electronic Theses and Dissertations

Infrared Phased-Array Antenna-Coupled Tunnel Diodes, Brian Alan Slovick

Electronic Theses and Dissertations

Low Noise And Low Repetition Rate Semiconductor-Based Mode-Locked Lasers, Dimitrios Mandridis

Electronic Theses and Dissertations

Convergence Of The Mean Shift Algorithm And Its Generalizations, Ting Hu

Electronic Theses and Dissertations

Bayesian Model Selection For Classification With Possibly Large Number Of Groups, Justin Kyle Davis

Electronic Theses and Dissertations

Variational Embedded Solitons, And Traveling Wavetrains Generated By Generalized Hopf Bifurcations, In Some Nlpde Systems, Todd Blanton Smith

Electronic Theses and Dissertations

Comparing Media Coverage Of The Gulf Oil Spill In The Us And Uk Implications For Global Crisis Communication, Sarah Crytzer

Electronic Theses and Dissertations

Ray Collection Bounding Volume Hierarchy, Kris Krishna Rivera

Electronic Theses and Dissertations

Movement Patterns, Survival, And Sightability Of White-Tailed Deer (Odocoileus Virginianus) In Eastern South Dakota, Kevin A. Robling

Electronic Theses and Dissertations

Productivity And Trophic Interactions In The Missouri River Impoundments, Mark J. Fincel

Electronic Theses and Dissertations

Crenulation Cleavage Development And The Influence Of Rock Microstructure On Crustal Seismic Anisotropy, Felice Maria Johanna Naus-Thijssen

Electronic Theses and Dissertations

Late-Pleistocene Glacial And Climate Fluctuations In The Torres Del Paine Region (51ºs), Southern South America, Juan Luis Garcia

Electronic Theses and Dissertations