Digital Commons Network^™

Hadron -Hadron Scattering In Lattice Quantum Chromodynamics, Aaron M. Torok

Doctoral Dissertations

Hadron-hadron and multi-hadron scattering calculations in fully dynamical, mixed-action Lattice Quantum Chromodynamics using the MILC gauge ensembles in a non-perturbative simulation are discussed. In particular, calculations of the pi+sum+, pi+xi 0, K+p, K+n, and K¯ 0xi0 scattering lengths are presented, and are the main subject of this dissertation. Using the two-flavor chiral expansion for extrapolation, the pion-hyperon scattering lengths are found to be ap+S+ = --0.197 +/- 0.017 fm, and ap+X0 = --0.098 +/- 0.017 fm, where the comprehensive error includes statistical and systematic uncertainties. Meson-meson and multi-meson lattice calculations by the NPLQCD collaboration are reviewed, and presented for completeness.

Mathematics Of Double-Walled Carbon Nanotube Model: Asymptotic Spectral And Stability Analysis, Miriam Rojas-Arenaza

Doctoral Dissertations

This dissertation is devoted to analytical study of a contemporary model of a double-walled carbon nano-tube. Carbon nano-tubes have been considered outstanding candidates to innovate and to promote emerging technologies, due to their remarkable chemical, mechanical, and physical properties. For these technologies, there is a need to develop mathematical models that capture the nature of the responses of these structures under a variety of physical conditions. Developing these models is challenging because the behavior lies on the borderline between classical and quantum systems. The main goal of the present dissertation is to prove mathematically rigorous results concerning the vibrational behavior …

Biologically Inspired Feature Extraction For Rotation And Scale Tolerant Pattern Analysis, Dragan Vidacic

Doctoral Dissertations

Biologically motivated information processing has been an important area of scientific research for decades. The central topic addressed in this dissertation is utilization of lateral inhibition and more generally, linear networks with recurrent connectivity along with complex-log conformal mapping in machine based implementations of information encoding, feature extraction and pattern recognition. The reasoning behind and method for spatially uniform implementation of inhibitory/excitatory network model in the framework of non-uniform log-polar transform is presented. For the space invariant connectivity model characterized by Topelitz-Block-Toeplitz matrix, the overall network response is obtained without matrix inverse operations providing the connection matrix generating function is …

Knowing More Than They Can Tell: An Assessment Of Genre Awareness Among Students In Writing Intensive Zoology And Civil Engineering Courses, Joleen Kidwell Hanson

Doctoral Dissertations

Developing genre awareness as a means of "learning how to learn" in new writing situations is a goal of four recently proposed writing pedagogies that recognize the context-dependent nature of standards for "good writing" (Devitt, Reiff, and Bawarshi (2004); Beaufort (2007); Johns (2008); Downs and Wardle (2007)). Yet other scholars argue that useful genre knowledge cannot be taught explicitly in the classroom, but must be acquired tacitly through participation in a workplace or other discourse community (Dias et al. (1999); Freedman (1994); Smit (2004)).

This qualitative study investigates the range of variability and potential sources of genre awareness among undergraduates …

Landslide Susceptibility Mapping Through Enhanced Dynamic Slope Stability Analysis Using Earth Observing Satellite Measurements, Ram Lakhan Ray

Doctoral Dissertations

Landslides are common throughout the world and can be triggered by earthquakes, volcanoes, floods, and heavy continuous rainfall in mountainous regions. For most types of slope failure, soil moisture plays a critical role because increased pore water pressure reduces the soil strength and increases stress. The combined effect of soil moisture in unsaturated soil layers and pore water pressure in saturated soil layers is critical to accurately predict landslides. However, dynamic in-situ soil moisture profiles are rarely measured on regional or global scales.

The dynamic soil moisture can be estimated by a soil vegetation atmosphere transfer (SVAT) model or satellite. …

Flow Within The Engineering Pipeline: Motivation Of High -Achieving Students During The High School To College Transition, Nick Tatar

Doctoral Dissertations

Student motivation is often related to perceptions of the learning environment, making the transition from high school to college a critical period as students adjust to new learning environments. It is also a critical time for engineering programs as high-achieving students who drop out of engineering during this period are not likely to be replaced.

A web-based survey including nine scales assessing personal motivation, perceived classroom goal structures, and academic related beliefs and behaviors was administered to eighty-eight students who participated at two time points---the end of senior year in high school and the end of the first semester in …

Ambient Measurements Of Chemical And Physical Properties Of Organic Aerosols: Insights Into Formation, Growth, And Heterogeneous Chemistry, Luke D. Ziemba

Doctoral Dissertations

Organic aerosols are a ubiquitous component of the troposphere, from heavily polluted cities to the remote Arctic. In Chapters II, III, and V of this dissertation, the formation of organic aerosol through observations of ambient size distributions is addressed. Chapter IV presents a new pathway for the formation of nitrous acid (HONO) in the urban atmosphere.

In Chapter II, the size-resolved chemical composition of sub-micron aerosol was measured at a suburban forested site in North Carolina. Two events were identified in which particle growth, presumably by gas-to-particle conversion, was dominated by accumulation of organic aerosol mass. Growth rates between 1.2 …

Fabrication And Tribology Of Composite Coatings Incorporating Solid Lubricant Micro-Reservoirs, Canan Gamze Guleryuz

Doctoral Dissertations

The tribological behavior of composite coating incorporating solid lubricant reservoirs has been investigated in this study. A new method, termed " microbeading" was devised to create microscopic reservoirs on the surface of sputter-deposited hard coatings. Pin-on-disk tests were used to evaluate the lubricating performance of these newly devised composite coatings. Three sizes of the reservoirs were investigated: 1.5, 5 and 10 microm. The 10 microm-sized-reservoirs performed better in terms of reducing friction and extending wear life. These coatings were also evaluated with finite element models. It was found that during ball-coating surface interaction, the lowest stresses and calculated work done …

Milling Cutter Software Architecture For Force And Surface Finish Modeling, Cuneyt Yalcin

Doctoral Dissertations

The main goal of this dissertation is to pave the way towards a milling simulation software platform that enables academic modeling research to be easily incorporated into industrial practice. The most significant contribution is creation of numeric structures that enable utilization of any milling cutting force model with any type of milling cutting tool in a computationally efficient manner. Efficiency and accuracy of the force and surface finish modeling are the main focus of this study.

Force modeling is an important part of milling research since it is directly connected to tool health and workpiece quality. A number of force …

Chemical Sensors Based On Swellable Polymer Microparticles And Molecular Imprinted Polymers, John Ong'any Osambo

Doctoral Dissertations

Swellable thermoresponsive and lightly cross-linked polymer microparticles were prepared for the development of chemical sensors for various target analytes. The swelling and shrinking of the polymer particles as a function of concentration of target analytes has been investigated using turbidity and fluorescence measurements at suitable pH values.

Chemical sensors that respond to transition metal ions such as Cu 2+, Ni2+, Zn2+, and Pb2+ were prepared by copolymerizing N-Isopropylacrylamide (NIPAAm) with ligands such as; 2,2'-acylamidodiacetic acid (AIDA), dibutyl-2,2'-(3 vinylphenylazanediyl) diacetate (DVPAA), N-((4'-methyl-2,2'-bipyridin-4yl)methyl)-N-propylacrylamide (NMPPAAm), and N,N-bis(pyridine-2-ylmethyl)prop-2-en-1-amine (NBPMPA). The microparticles were either labeled with 9-vinylanthracene (9-VA)/2-Naphthylmethacrylate (2-NMA), or fluorescein o-acrylate/methacryloxethyl thiocarbonyl rhodamine B …

Predicting Inclusive Teaching Using The Transtheoretical Model Of Behavior Change And The Theory Of Planned Behavior, Heather D. Hussey

Doctoral Dissertations

The diversity related materials in many university and college courses do not reflect the extent of diversity in society (Banks, 2002). Attempts to diversify curriculum have been made (Montgomery, 2001; Richards, Brown, & Forde, 2007), but further work is needed to prepare students to thrive in a culturally diverse society (Banks, 2002; Marshall, 2002). Research regarding faculty views toward diversity on campus and in the curriculum is limited (Brunner, 2006; Piland, Hess, & Piland, 2000; Wasonga & Piveral, 2004). Although a majority of faculty believe that a diversified institution and curriculum is positive, little research has examined the types of …

Development Of Nitrogen Protecting Groups And Synthesis And Complexation Of Bridged Bis-Tetraazamacrocycles, Matthew J. Young

Doctoral Dissertations

The development of nitrogen-protecting groups that are orthogonal to the N-benzyl group for use in cross-bridged tetraazamacrocycles and the synthesis and complexation of bridged bis-tetraazamacrocycles are presented. The allyl, p-methoxybenzyl (PMB), and 2-naphthylmethyl (Nap) nitrogen-protecting groups were investigated for use on cross-bridged tetraazamacrocycle systems and conditions for deprotection were found for the N-allyl and N-PMB protecting groups. The conditions applied for the cleavage of the N-allyl and N-PMB groups and the systems that these conditions were employed on are illustrated below. This research has demonstrated that the N-allyl and N-PMB protecting groups are applicable to a variety of systems. These …

A Computational Study On Novel Carbon-Based Lithium Materials For Hydrogen Storage And The Role Of Carbon In Destabilizing Complex Metal Hydrides, Mohammed Minhaj Ghouri

Doctoral Dissertations

One of the major impediments in the way of the realization of hydrogen economy is the storage of hydrogen gas. This involves both the storage for stationary applications as well as that of storage onboard vehicles for transportation applications. For obvious reasons, the system targets for the automotive applications are more stringent. There are many approaches which are still being researched for the storage of hydrogen for vehicular applications. Among them are the high pressure storage of hydrogen gas and the storing of liquid hydrogen in super insulated cryogenic cylinders. While both of them have been demonstrated practically, the high …

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 …

Meta-Learning Computational Intelligence Architectures, Ryan J. Meuth

Doctoral Dissertations

"In computational intelligence, the term 'memetic algorithm' has come to be associated with the algorithmic pairing of a global search method with a local search method. In a sociological context, a 'meme' has been loosely defined as a unit of cultural information, the social analog of genes for individuals. Both of these definitions are inadequate, as 'memetic algorithm' is too specific, and ultimately a misnomer, as much as a 'meme' is defined too generally to be of scientific use. In this dissertation the notion of memes and meta-learning is extended from a computational viewpoint and the purpose, definitions, design guidelines …

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

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 …

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

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 …

A Critical Hermeneutic Approach To Understanding Experiences Of Selected Afghan-Muslim-American Leaders Post-9/11 In The Diverse Bay Area, Belal A. Kaifi

Doctoral Dissertations

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Children Appropriating A New World Of Hope In Peru, Paraguay, And Haiti, Luis Enrique Bazan

Doctoral Dissertations

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Nurse Educators' Implementation Of Concept Mapping, Case Studies, And Reflective-Thinking Exercises In Undergraduate Didactic Nursing Courses At Baccalaureate Schools Of Nursing, Danette Kathleen Dutra

Doctoral Dissertations

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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 …

Anti Wetting Additives For Aluminosilicate Refractories In Molten Aluminum Contact Applications, Devdutt Pramod Shukla

Doctoral Dissertations

"Aluminosilicate based refractories are widely used in furnace installations for melting aluminum because they are inexpensive, readily available and generally exhibit the properties desired from a refractory material. However, they face severe corrosion and degradation issues due to the extremely reducing nature of molten aluminum alloys. Isothermal static cup testing is widely used as a tool to evaluate the performance of refractories against penetration by molten aluminum alloys. Various testing methods were reviewed and an upgraded static cup test was recommended. Commercially available aluminosilicate refractories were tested using this method and their results were studied in order to understand the …

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 …

Fundamentals Of Friction Stir Spot Welding, Harsha Badarinarayan

Doctoral Dissertations

"The recent spike in energy costs has been a major contributor to propel the use of light weight alloys in the transportation industry. In particular, the automotive industry sees benefit in using light weight alloys to increase fuel efficiency and enhance performance. In this context, light weight design by replacing steel with Al and/or Mg alloys have been considered as promising initiatives. The joining of structures made of light weight alloys is therefore very important and calls for more attention. Friction Stir Spot Welding (FSSW) is an evolving technique that offers several advantages over conventional joining processes.

The fundamentals aspects …

Applications Of Sensor Arrays In Acoustic And Seismic Signal Processing, Peng Xie

Doctoral Dissertations

"This work investigates the applications of sensor arrays in the areas of acoustic and seismic signal processing. It comprises three papers.

The first paper explores the problem of blind source separation (BSS) for convolutive acoustic signals. It concentrates on the well known permutation and amplitude problems in frequency-domain BSS and proposes a new hybrid approach to solve them. This approach connects the separation processes across all frequency bins, and relies on a novel permutation control unit. This framework could greatly reduce computational load and improve separation performance. Synthesized and real-world experiments demonstrate its efficiency.

The second paper investigates a new …

Systematic Functional And Object-Oriented Product Design Frameworks, Jen-Chi Wu

Doctoral Dissertations

"The existing co-design methods of mechatronic products focus on co-design of mechanical and electronic components or co-design of computer hardware and software components. There exist no effective co-design methods for mechanical, electronic and software components at the concept design stage. The research objective of this dissertation work is to develop more effective systematic product design approaches for co-design of mechatronic products. Three innovative functional and object-oriented integrated design frameworks and one virtual prototyping application, which leverages on these three design frameworks, have been developed for co-design of mechatronic products. The three frameworks are: I) Hierarchical Object-Oriented Functional Modeling Framework, 2) …

Modeling And Analysis Of Noise Coupling In Multilayer Power/Ground Planes, Gang Feng

Doctoral Dissertations

"The simultaneous switching noise (SSN) in a multilayer power delivery network (PDN) is a critical problem in high-speed printed circuit board (PCB) designs. Full-wave methods are not computationally efficient for analyzing PCB structures normally with a multi-scale nature. In this thesis, a model for multilayer power/ground planes is proposed using basic plane pair blocks derived from the cavity model combined with the segmentation technique. Vias and other circuit elements can further be easily integrated in the multilayer plane model. As a result, the entire PDN model is much more computationally efficient than full-wave methods. Experimental and numerical results have validated …

F₂-Isoprostanes Study After Exposure To Selected Nanoparticles By Liquid Chromatography/Tandem Mass Spectrometry And Investigation Of Nanoparticles On The Cytotoxicity Effect Of Arsenic In Vitro, Xiaoqian Liu

Doctoral Dissertations

"Nanopartices as a new class of materials found their applications in industry, aerospace, clinical diagnosis and cancer therapy. Recently, the health effects of nanoparticles have caused people great concerns. This dissertation studies the mechanisms of nanoparticle cytotoxicity in human lung epithelial cells (A549). F₂-isoprostanes are novel reliable biomarkers for lipid peroxidation. In the first part of this work, total free F₂-isoprostanes were quantified by high performance liquid chromatography/mass spectrometry followed by the exposure of SiO₂ (15 nm), CeO₂ (20 nm), Fe₂O₃ (30 nm), and ZnO (70 nm) nanoparticles for 24 hours. For the first time, the results showed that F₂-isoprostanes …