Physical Sciences and Mathematics Commons^™

Confluence Of Vision And Natural Language Processing For Cross-Media Semantic Relations Extraction, Amara Tariq

Electronic Theses and Dissertations

In this dissertation, we focus on extracting and understanding semantically meaningful relationships between data items of various modalities; especially relations between images and natural language. We explore the ideas and techniques to integrate such cross-media semantic relations for machine understanding of large heterogeneous datasets, made available through the expansion of the World Wide Web. The datasets collected from social media websites, news media outlets and blogging platforms usually contain multiple modalities of data. Intelligent systems are needed to automatically make sense out of these datasets and present them in such a way that humans can find the relevant pieces of …

Computational Study Of Traveling Wave Solutions And Global Stability Of Predator-Prey Models, Yi Zhu

Electronic Theses and Dissertations

In this thesis, we study two types of reaction-diffusion systems which have direct applications in understanding wide range of phenomena in chemical reaction, biological pattern formation and theoretical ecology. The first part of this thesis is on propagating traveling waves in a class of reaction-diffusion systems which model isothermal autocatalytic chemical reactions as well as microbial growth and competition in a flow reactor. In the context of isothermal autocatalytic systems, two different cases will be studied. The first is autocatalytic chemical reaction of order $m$ without decay. The second is chemical reaction of order $m$ with a decay of order …

Laser Filament Interaction With Aerosols And Clouds, Cheonha Jeon

Electronic Theses and Dissertations

A high powered ultrashort laser pulse can propagate as a diffraction-free self-channeled structure called a filament, created by a combination of nonlinear processes. With its ability to convey extremely high intensity beams to distant targets, many applications such as remote sensing, cloud seeding, and discharge guiding are potentially possible. However, one of the main challenges of outdoor field applications is the laser propagation through the atmosphere where pressure fluctuations and concentrations of aerosols may be present. The rationale behind the work presented in this dissertation is to evaluate the robustness of the filamentation, measure the interaction losses as well as …

Design And Engineering Of Ultrafast Amplifier Systems, Benjamin Webb

Electronic Theses and Dissertations

Recently, the design and engineering of ultrafast laser systems have led to an extraordinary increase in laser power and performance which have brought about advances in many fields such as medicine, material processing, communications, remote sensing, spectroscopy, nonlinear optics, and atomic physics. In this work, several ultrafast amplification techniques -- including chirped-pulse amplification (CPA), optical parametric chirped-pulse amplification (OPCPA), and divided-pulse amplification (DPA) -- are described and demonstrated in the design and construction of two ultrafast laser facilities. An existing Ti:Sapphire laser system was completely redesigned with an increased power of 10 TW for experiments capable of generating hundreds of …

Analysis Of Commutativity With State-Chart Graph Representation Of Concurrent Programs., Kishore Debnath

Electronic Theses and Dissertations

We present a new approach to check for Commutativity in concurrent programs from their run-time state-chart graphs. Two operations are said to be commutative if changing the order of their execution do not change the resultant effect on the working object. Commutative property is capable of boosting performance in concurrent transactions such that transactional concurrency is comparable to a non-blocking linearizable version of a similar data structure type. Transactional concurrency is a technique that analyses object semantics, as object states, to determine conflicts and recovery between conflicting operations. Processes that commute at object level can be executed concurrently at transaction …

Quinolines: Novel Synthesis And Derivatives Of Heterocyclic Bioactive Agents, Ginelle A. Ramann

Electronic Theses and Dissertations

Tuberculosis is a pulmonary disease that has ravaged the world throughout history. Even today, many developed and developing countries are experiencing this plight, made worse by the scourge of antibiotic-resistant bacteria.

Mycobacterium tuberculosis's class II fructose-1,6-bisphosphate aldolase presents an interesting target in the design of new therapies against this disease. Previous attempts to construct an inhibitor to this enzyme fell short due to poor selectivity or poor cellular uptake. However a new class of noncompetitive inhibitor based on 8-hydoxyquinoline-2-carboxylic acid presents a fresh approach. Preliminary studies indicate various modifications to this scaffold could be beneficial to its inhibitory efficacy.

Modifications …

Evaluating Floating Treatment Wetlands To Improve Nitrogen Removal In A Wet Detention Pond, Zachary Marimon

Electronic Theses and Dissertations

Wet detention ponds are used for stormwater treatment across the United States and reduce most pollutants by at least 60%, but only remove 30% of total nitrogen. Floating Treatment Wetlands (FTWs) are an emerging technology that uses aquatic plants suspended in the pelagic zone to remove nitrogen through vegetative assimilation and microbial denitrification. A before-after field experiment evaluated nitrogen removal in a an existing pond in Orlando, FL, retrofitted with BioHaven® FTWs planted with the aquatic macrophytes Juncus effusus (Soft Rush) and Pontederia cordata (Pickerelweed). Surface water samples were used to compare the nitrogen removal performance of the pond under …

Fabrication And Characterization Of Spatially-Variant Self-Collimating Photonic Crystals, Jennefir Digaum

Electronic Theses and Dissertations

Spatially-variant photonic crystals (SVPCs) created using materials having a low refractive index are shown to be capable of abruptly controlling light beams with high polarization selectivity. SVPCs are photonic crystals for which the orientation of the unit cell is controllably varied throughout the lattice to control the flow of light. Multi-photon lithography in a photo polymer was used to fabricate three-dimensional SVPCs that direct the flow of light around a 90 degree bend. The optical performance of the SVPCs was characterized using a scanning optical-fiber system that introduced light onto the input face of a structure and measured the intensity …

Geometric-Based Algorithm For A Full Row-Rank System Matrix Along Multiple Directions In Dt, Igor Lutsenko

Electronic Theses and Dissertations

Discrete tomography (DT) is an image reconstruction procedure that deals with computational synthesis of a cross-sectional image of an object from either transmission or reflection data collected by penetrating an object with X-rays from a small number of different directions, and whose range of the underlying function is discrete. Image reconstruction using algebraic approach is time consuming and the computation cost depends on the size of the system matrix. More scanning directions provide an increase in the reconstructed image quality, however they increase the size of the system matrix dramatically. Deletion of linearly dependent rows of this matrix is necessary …

Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta

Electronic Theses and Dissertations

Ferruginous hawks (Buteo regalis) are a grassland and shrubland obligate nesting raptor and prefer lightly grazed pasture or idle areas for nesting. Their population reportedly declines in number if more than 30% of an area is cultivated and they rarely nest in areas dominated by croplands. Golden eagles (Aquila chrysaetos) are long-lived raptors with high nest-site fidelity and relatively low reproductive success. Population trends of golden eagles in western United States are unclear although long-term monitoring of populations shows declines in occupancy and breeding performance. Northern harriers (Circus cyaneus) prefer relatively open grasslands and …

Perchlorate Variations Over 300 Years: Influence Of Human Activities, Volcanic Eruptions And Bolide Events, Kari Peterson

Electronic Theses and Dissertations

Perchlorate, which derives from both anthropogenic and natural sources in the current environment, constitutes a significant health risk to humans because it competitively inhibits iodine uptake by the thyroid gland. Thus, there has been considerable interest in reducing the human exposure to environmental perchlorate by limiting the release of perchlorate from anthropogenic sources. However, a lack of understanding of the relative contributions from anthropogenic and natural sources has prevented widespread regulation. A 300-year ice core perchlorate record from Summit Station, Greenland (1700-2007 C.E.) that extends beyond the onset of the Industrial Revolution (1850 C.E.) is used to assess the anthropogenic …

Ice Concentration Linked With Extractive Stirrer (Icecles), Nujud Omar Maslamani

Electronic Theses and Dissertations

Clean water is very important for human health. Therefore, drinking water contamination is a significant research concern, especially with the increasing global population. Some contaminants, such as pesticides, can cause health effects even at low levels. Therefore, trace and ultratrace analysis of contaminants in drinking water is essential. Ultratrace analysis typically requires highly effective sample preparation methods and/or highly sensitive instruments. There are currently advanced sample preparations techniques available to analytical chemists that may allow trace analysis of certain analytes. These include liquid-liquid extraction (LLE), solid phase extraction (SPE), solid phase micro extraction (SPME), and stir bar sorpitive extraction (SBSE). …

Similarity Measurement Of Breast Cancer Mammographic Images Using Combination Of Mesh Distance Fourier Transform And Global Features, Ravi Kasaudhan

Electronic Theses and Dissertations

Similarity measurement in breast cancer is an important aspect of determining the vulnerability of detected masses based on the previous cases. It is used to retrieve the most similar image for a given mammographic query image from a collection of previously archived images. By analyzing these results, doctors and radiologists can more accurately diagnose early-stage breast cancer and determine the best treatment. The direct result is better prognoses for breast cancer patients. Similarity measurement in images has always been a challenging task in the field of pattern recognition. A widely-adopted strategy in Content-Based Image Retrieval (CBIR) is comparison of local …

Changes In Wetland Conditions And Wetland Plant Communities In The Prairie Pothole Region After 50 Years, Ryann Cressey

Electronic Theses and Dissertations

Wetlands in Stutsman County, North Dakota were revisited after 50 years to assess changes in wetland conditions and plant communities within wetland zones in the Prairie Pothole Region. In 1961-1966, Robert E. Stewart and Harold A. Kantrud conducted a study to investigate the relationship of wetland plant communities to variations of water permanence and chemistry on three study areas: Crystal Springs, Cottonwood, and Mt. Moriah. Within in this region, a severe drought occurred in 1988- 1992 followed by the longest deluge starting in 1993 with wetlands still impacted today. In 2013 and 2014, I revisited 80 of the original wetlands …

Bioinformatics Investigation On The Role Of Obox Gene Family In Preimplantation Embryo Development, Wei Wang

Electronic Theses and Dissertations

Preimplantation embryo development (PED) refers to the period from fertilization to implantation in mammals. This complex process is critical for successful implantation and pregnancy. Although studies on PED have been conducted, using mainly the mouse as a model organism, the gene regulatory mechanisms are still not well understood. The next-generation sequencing technologies enable researchers to obtain the genome-wide expression profiling with single-cell resolution, which are powerful tools to study early embryogenesis. We used the single-cell RNA sequencing datasets that are available in the public domain and conducted bioinformatics analysis of expression profiling from zygote to blastocyst. Through hierarchical clustering of …

Ecology Of Largemouth Bass In An Aging Reservoir: Implications For Creating A Trophy Largemouth Bass Fishery, Jason Breeggemann

Electronic Theses and Dissertations

There are an estimated 3-9 million small reservoirs and nearly 1,000 large reservoirs in the United States. Most of these reservoirs were built several decades ago and are experiencing symptoms of reservoir aging, including loss of habitat, sedimentation, and decreased fishery production. Furthermore, over the last several decades, there has been an increasing interest among anglers for high quality, trophy fisheries. However, little is known about exactly how the reservoir aging process affects the ecology and especially growth potential of Largemouth Bass, particularly under potential climate change scenarios. Grand Lake in TX is a 45ha ageing reservoir that was built …

Effect Of Oil And Natural Gas Development On Survival And Health Of White-Tailed Deer In The Western Dakotas, Katherine L. Moratz

Electronic Theses and Dissertations

Oil and gas development in North Dakota has resulted in the need for information regarding how increased activity has affected white-tailed deer (Odocoileus virginianus) populations. We evaluated white-tailed deer ecology in response to energy development and hypothesized that oil and gas development would negatively affect adult and neonate white-tailed deer due to increased vehicle traffic and human-related effects. We captured and radio-collared adult female and neonate white-tailed deer across three study areas: Dunn County, North Dakota, an area influenced by energy development, and Grant County, North Dakota, and Perkins County, South Dakota, areas not impacted by energy development at this …

Degradation Of Hexachlorobenzene, Pentachlorophenol And Pentachloroanisole Using Activated Magnesium In An Acidified Ethanol/Ethyl Lactate Cosolvent System, Amel Garbou

Electronic Theses and Dissertations

For many centuries, chemists have dedicated many labor-intensive hours to improving the quality of life for mankind by developing synthetic methods for the production of compounds which fulfill the needs and meet the demands of society. However, the innovation of such compounds has frequently come at the cost of detrimental side-effects that do not always present themselves until many years, or even decades, following their initial application. Many compounds in this category come in the form of globally-distributed halogenated molecules which are toxic to many living organisms, susceptible to bioaccumulation and resistant to biodegradation processes. Such compounds are classified as …

Conformations And Dynamics Of Semi-Flexible Polymers, Aiqun Huang

Electronic Theses and Dissertations

In this dissertation, we investigate the conformations, transverse fluctuations and dynamics of two-dimensional (2D) semi-flexible polymers both in the bulk and under channel confinement. We present unified scaling relations in regard to various quantities of interest for a broad range of combinations of chain length and chain stiffness using Langevin dynamics simulation. We also present a three-dimensional (3D) heterogeneous semi-flexible chain model for a double stranded DNA (dsDNA). Our model not only confirms the established findings for homogeneous dsDNA, but also predicts new physical phenomenon for heterogeneous dsDNA. The problems studied in this dissertation are relevant to analysis of the …

Structure-Preserving Finite Difference Methods For Linearly Damped Differential Equations, Ashish Bhatt

Electronic Theses and Dissertations

Differential equations (DEs) model a variety of physical phenomena in science and engineering. Many physical phenomena involve conservative or dissipative forces, which manifest themselves as qualitative properties of DEs that govern these phenomena. Since only a few and simplistic models are known to have exact solutions, approximate solution techniques, such as numerical integration, are used to reveal important insights about solution behavior and properties of these models. Numerical integrators generally result in undesirable quantitative and qualitative errors . Standard numerical integrators aim to reduce quantitative errors, whereas geometric (numerical) integrators aim to reduce or eliminate qualitative errors, as well, in …

Computational Approaches For Binning Metagenomic Reads, Ying Wang

Electronic Theses and Dissertations

Metagenomics uses sequencing technologies to study genetic sequences from whole microbial communities. Binning metagenomic reads is the most fundamental step in metagenomic studies, which is essential for the understanding of microbial functions, compositions, and interactions in environmental samples. Various taxonomy-dependent and taxonomy-independent approaches have been developed based on information such as sequence similarity, sequence composition, or k-mer frequency. However, there is still room for improvement, and it is still challenging to bin reads from species with similar or low abundance or to bin reads from unknown species. In this dissertation, we introduce one taxonomy-independent and three taxonomy-dependent approaches to improve …

Follower And Extender Sets In Symbolic Dynamics, Thomas Kelly French

Electronic Theses and Dissertations

Given a word w in the language of a one-dimensional shift space X, the follower set of w, denoted F_X(w), is the set of all right-infinite sequences which follow w in some point of X. Extender sets are a generalization of follower sets and are defined similarly. To a given shift space X, then, we may associate a follower set sequence {|F_X(n)|} which records the number of distinct follower sets in X corresponding to words of length n. Similarly, we may define an extender set sequence {|E …

The Effect Of Hyperparameters In The Activation Layers Of Deep Neural Networks, Clay Lafayette Mcleod

Electronic Theses and Dissertations

Deep neural networks (DNNs), and artificial neural networks (ANNs) in general, have recently received a great amount of attention from both the media and the machine learning community at large. DNNs have been used to produce world-class results in a variety of domains, including image recognition, speech recognition, sequence modeling, and natural language processing. Many of most exciting recent deep neural network studies have made improvements by hardcoding less about the network and giving the neural network more control over its own parameters, allowing flexibility and control within the network. Although much research has been done to introduce trainable hyperparameters …

The Porosity And Permeability Distribution Of The Shoal Grainstone And Thrombolitic Facies Of The Smackover Formation In Little Cedar Creek And Brooklyn Fields In Southwestern Alabama, Devin Thomas

Electronic Theses and Dissertations

The Smackover Formation is the most prolific hydrocarbon producer in Alabama, with the Little Cedar Creek and Brooklyn Fields being the two largest producers in Alabama. Unlike other Smackover fields Little Cedar Creek Field and Brooklyn Field production is the result of two reservoirs, known as the shoal grainstone and thrombolite (microbial) boundstone. Even with the success of the Smackover Formation, geographic trends of the porosity and permeability are problematic because production is affected. The distribution of the facies also plays a role in the porosity and permeability. The objective of this study is to delineate porosity and permeability trends …

Synthesis And Characterization Of Anhydrous Proton Conducting Polymer Electrolytes For Fuel Cell Applications, Buddika Mayomi Liyanage

Electronic Theses and Dissertations

Anhydrous H+ ion conducting and high temperature capability of polymer electrolytes are being investigated for use in applications such as batteries, fuel cells, electro chromic windows and light emitting devices. Fuel cells are efficient electrochemical energy conversion devices; they can generate greener energy from chemical fuels. The polymer electrolyte membrane is heart of most fuel cell designs separating the oxidant and fuel chambers and providing the medium to conduct H+ ions between the anode and the cathode. Our goal is to understand the molecular level details of anhydrous H+ conductivity through the synthesis and characterization of polymer electrolytes based on …

Temperature And Pressure Effects On Elastic Properties Of Relaxor Ferroelectrics And Thermoelectrics: A Resonant Ultrasound Spectroscopy Study, Sumudu Tennakoon

Electronic Theses and Dissertations

Relaxor ferroelectric lead magnesium niobate-lead titanate (PMN-PT) material exhibits exceptional electromechanical properties. The material undergoes a series of structural phase transitions with changes in temperature and the chemical composition. The work covered in this dissertation seek to gain insight into the phase diagram of PMN-PT using temperature and pressure dependence of the elastic properties. Single crystal PMN-PT with a composition near morphotropic phase boundary (MPB) was investigated using a resonant ultrasound spectroscopy (RUS) methodologies in the temperature range of 293 K - 800 K and the pressure range from near vacuum to 3.4 MPa. At atmospheric pressure, significantly high acoustic …

Blow-Up Solution And Blow-Up Rate Of Bose-Einstein Condensates With Rotational Term, Nyla Basharat

Electronic Theses and Dissertations

In this thesis, we discuss the Gross Pitaevskii Equation (GPE) with harmonic potential and with an angular momentum rotational term in space R^{^2}, which describes the model for Bose-Einstein Condensation. Local Well-Posedness of the equation and the conservation identities for mass, energy and angular momentum are presented. Using the virial identities, we derive the condition for blow-up solution in finite time. Then a threshold of L^{^2} norm of wave function is obtained for global existence, of GPE in term of ground state solution. This method allows us to obtain our main result ``Sharp sufficient condition for global …

A Partition Function Connected With The Göllnitz-Gordon Identities, Nicolas A. Smoot

Electronic Theses and Dissertations

Nearly a century ago, the mathematicians Hardy and Ramanujan established their celebrated circle method to give a remarkable asymptotic expression for the unrestricted partition function. Following later improvements by Rademacher, the method was utilized by Niven, Lehner, Iseki, and others to develop rapidly convergent series representations of various restricted partition functions. Following in this tradition, we use the circle method to develop formulas for counting the restricted classes of partitions that arise in the Gollnitz-Gordon identities. We then show that our results are strongly supported by numerical tests. As a side note, we also derive and compare the asymptotic behavior …

Gallai-Ramsey Number Of An 8-Cycle, Jonathan Gregory

Electronic Theses and Dissertations

Given a graph G and a positive integer k, define the Gallai-Ramsey number to be the minimum number of vertices n such that any k-edge-coloring of Kn contains either a rainbow (all different colored) triangle or a monochromatic copy of G. In this work, we establish the Gallai-Ramsey number of an 8-cycle for all positive integers.

Combinatorial Optimization Of Subsequence Patterns In Words, Matthew R. Just

Electronic Theses and Dissertations

Packing patterns in words concerns finding a word with the maximum number of a prescribed pattern. The majority of the work done thus far is on packing patterns into permutations. In 2002, Albert, Atkinson, Handley, Holton and Stromquist showed that there always exists a layered permutation containing the maximum number of a layered pattern among all permutations of length n. Consequently, the packing density for all but two (up to equivalence) permutation patterns up to length 4 can be obtained. In this thesis we consider the analogous question for colored patterns and permutations. By introducing the concept of colored blocks …