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Piezoelectric Structures With Circuitry Integration For Wave Guiding And Energy Manipulation, Jiawen Xu

Doctoral Dissertations

The objective of this dissertation research is on the designing and optimization of promising wave guiding and energy manipulation approach. Specifically address above-mentioned issues of modeling and application of piezoelectric metamaterials and energy harvesting. The first research task is to develop fundamental modeling and understanding of piezoelectric metamaterial integrated with LC shunts to create local resonances. We establish the lumped-parameter model. Taking advantage of the model, we identify the influence of a key parameter to the behavior of the metamaterial. The second research task is to explore the application of the piezoelectric metamaterials in acoustic wave guiding. This work is …

Controlling Enterohemorrhagic E. Coli O157: H7 Using Selenium And Rutin, Meera Surendran Nair

Doctoral Dissertations

Enterohemorrhagic E.coli O157: H7 (EHEC) has emerged as one of the leading causes of food borne illness and pediatric diarrheal disease in the United States. The EHEC associated life-threatening hemolytic uremic syndrome in human patients is linked to the expression of several virulence factors of the pathogen, especially verotoxins. Verotoxins (VT) or shiga like toxins (Stx) are the major virulence factors elaborated by EHEC. Even after 30 years of research on EHEC epidemiology and pathogenesis, little advancement has been made in disease prevention and treatment against the bacterium. One of the main limitations in treating EHEC infection is the contraindicated …

Exploring Heterogeneities Near Earth’S Inner Core Boundary With Seismic Body Waves, Manawaduge S. Desilva

Doctoral Dissertations

The mechanism of inner core solidification drives the compositional and thermal convection in outer core, sustaining the Earth’s geodynamo. Hence any differences in the manner of crystal growth at the continuously growing inner core boundary(ICB) is essential in understanding secular variations of geomagnetic field.

By applying boundary element methods(BEM) to synthesize compressional waves, effects of ICB topography are predicted and compared with waveform observations in pre-critical, critical, post-critical, and diffraction ranges of the wave reflected from the ICB(PKiKP). In the pre-critical range, data require an upper bound of 2km at 1-20km wavelength for any ICB topography. Higher topography sharply reduces …

Optimization And Bayesian Inference In Model-Based Decision Making, Ali Abdollahi

Doctoral Dissertations

The focus of this dissertation is on using optimization and Bayesian inference in model-based decision making. We discuss two problems: (a) optimal battery charging and battery life management; (b) fault diagnosis using probabilistic graphical models. In the first part of this thesis, we address the optimal charging problem using a two-time-scale algorithm which performs fast-charging at the lower-level (fast time-scale), while managing the battery life at the higher-level (low time-scale). At the lower-level, we derive optimal charging algorithms for Li-ion batteries using equivalent electrical circuit models and quadratic optimization approaches. The objective function is considered as a linear combination of …

An Empirical Analysis Of The Role Of Unionization In Variations In Income Inequality Across Selected U.S. Metropolitan Areas In 1990, 2000 And 2010, Qinglin Hu

Doctoral Dissertations

Archival abstract submitted.

The Voices Of Nurses Who Serve: A Dissertation Examining Nurses On Governing Boards, Lisa J. Sundean Phd

Doctoral Dissertations

Archival abstract submitted

Polymer Nanocomposites And Biomaterials: From Chemical Cross-Linking To 3d Printing, Huseini Patanwala

Doctoral Dissertations

Part 1:

Aerogel is an open-celled, microporous, solid foam composed of a network of interconnected structures formed by replacing the solvent in wet gel with air. Integrating the intrinsic mechanical and electrical properties of carbon nanotubes (CNTs) with those of an aerogel provides a new class of material with unique multifunctional properties which may find applications not limited to fuel cells, super capacitors and batteries. I attempt at improving the mechanical integrity by first functionalizing the CNTs with carboxylic (-COOH) groups and subsequently cross-linking the CNTs using diisocyanate to form polyurea-CNT (PUA-CNT) composite aerogels. Mechanical properties of the final PUA-CNT …

Playful Assessment: A Game-Based Approach To Assessing Teachers’ Competency For The Wise Integration Of Technology In The Classroom, Beomkyu Choi

Doctoral Dissertations

The goal of this dissertation was to document and analyze ways in which a game can be a valid and useful assessment of teachers’ competency for the wise integration of technology in the classroom. Using concepts from ecological psychology and situated cognition, this study analyzed card and board games as measures of the situative and interactive aspect of teachers’ pedagogical design thinking in relation to technology integration. To achieve this goal, this dissertation project was comprised of three studies, featuring a theoretical framework whitepaper, a design experiment report, and an omnibus research study.

Chapter 1 describes teachers’ on-the-fly pedagogical reasoning …

Study Of A Gp5-Mosaic T-Cell Vaccine In Protection Of Swine Against Heterologous Prrsv Strains, Junru Cui

Doctoral Dissertations

Porcine reproductive and respiratory syndrome (PRRS) causes significant economic losses due to reproductive failure and respiratory disease. The high genetic and antigenic diversity of PRRSV makes the control of this disease very challenging. Current vaccines cannot provide adequate protection to the circulating PRRSV strains; therefore, vaccines can confer cross-protection are in urgent demand. Two T-cell mosaic vaccines were designed based on 748 GP5 sequences using the Mosaic T-Cell Vaccine Tool Suite from the Los Alamos National Laboratory. These mosaic sequences were then used to construct DNA vaccines. Significantly higher levels of interferon-γ mRNA and virus-specific antibodies, rapid virus clearance in …

Semantics, Meaning, Truth And Content: Disentangling Linguistic And Philosophical Approaches To The Study Of Meaning, Toby Napoletano

Doctoral Dissertations

The purpose of this dissertation is to clarify the relationship between two research programs engaged in the investigation of linguistic meaning: the philosophy of language, broadly conceived, and semantics as it is pursued within generative linguistics.

It is often assumed that philosophers of language and semanticists in linguistics are working broadly within the same research program, addressing the same questions about language, its meaning, and its use. At least, it is assumed that the two research programs are continuous with one another, so that each places important constraints on the other. Philosophical theories of meaning, the thought goes, must square …

Structure And Function Of Protein Kinase R, Christopher B. Mayo

Doctoral Dissertations

Protein Kinase R (PKR) is a central component of the innate immunity antiviral pathway and is activated by dsRNA. PKR contains two tandem dsRNA binding domains and a C-terminal kinase domain. In the canonical activation model, binding of multiple PKR monomers to dsRNA enhances dimerization of the kinase domain, leading to enzymatic activation. A minimal dsRNA length of 30 bp is required for activation. However, short (~15 bp) stem-loop RNAs containing flanking single stranded tails (ss-dsRNAs) are capable of activating PKR. Here, we characterize the structural features of ss-dsRNAs that contribute to activation. We have designed a model ss-dsRNA containing …

Electrochemical Behavior Of Dense Electrodes For Impedancemetric Nox Sensors, Nabamita Pal

Doctoral Dissertations

NOx (NO and NO2) exhaust gas sensors for diesel powered vehicles have traditionally consisted of porous platinum (Pt) electrodes along with a dense ZrO2 based electrolyte. Advancement in diesel engine technology results in lower NOx emissions. Although Pt is chemically and mechanically tolerant to the extreme exhaust gas environment, it is also a strong catalyst for oxygen reduction, which can interfere with the detection of NOx at concentrations below 100 ppm. Countering this behavior can add to the complexity and cost of the conventional NO x sensor design. Recent studies have shown that dense electrodes are less prone to heterogeneous …

Stretching The Limits Of Dynamic Range, Shielding Effectiveness, And Multiband Frequency Response, Matthew J. Hartmann

Doctoral Dissertations

In this dissertation, an RF MEMS variable capacitor suitable for applications requiring ultrawide capacitive tuning ranges is reported. The device uses an electrostatically tunable liquid dielectric interface to continuously vary the capacitance without the use of any moving parts. As compared to existing MEMS varactors in literature, this device has an extremely simple design that can be implemented using simple fabrication methods that do not necessitate the use of clean room equipment. In addition, this varactor is particularly suited for incorporating a wide range of liquid dielectric materials for specific tuning ratio requirements.

Additionally, the shielding effectiveness performance of graphene-doped …

Full Simulation For The Qweak Experiment At 1.16 And 0.877 Gev And Their Impact On Extracting The Pv Asymmetry In The N→Δ A Transition, Hend Abdullah Nuhait

Doctoral Dissertations

The Qweak project is seeking to find new physics beyond the Standard Model. It is aimed to measure the weak charge of the proton, which has never been measured, at 4% precision at low momentum transfer. The experiment is performed by scattering electrons from protons and exploiting parity violation in the weak interaction at low four-momentum transfer.

In this experiment, two measurements were considered: which are elastic and inelastic. The elastic is to measure the proton's weak charge. In addition, the inelastic asymmetry measurement, which will extract the low energy constant dΔ. That measurement works in the neutral current …

Motion-Capture-Based Hand Gesture Recognition For Computing And Control, Andrew Gardner

Doctoral Dissertations

This dissertation focuses on the study and development of algorithms that enable the analysis and recognition of hand gestures in a motion capture environment. Central to this work is the study of unlabeled point sets in a more abstract sense. Evaluations of proposed methods focus on examining their generalization to users not encountered during system training.

In an initial exploratory study, we compare various classification algorithms based upon multiple interpretations and feature transformations of point sets, including those based upon aggregate features (e.g. mean) and a pseudo-rasterization of the capture space. We find aggregate feature classifiers to be balanced across …

Understanding The Surface Fouling Mechanism Of Ultrananocrystalline Diamond Microelectrodes Using Microfluidics For Neurochemical Detection, An-Yi Chang

Doctoral Dissertations

Electrochemical methods are widely used for chronic neurochemical sensing, but thus far, the organic solution redox reactions fouled the electrodes' surface. It caused the reduction of sensitivity and the electrodes' lifetime.

Here, we present the boron-doped nanocrystalline diamond microelectrodes (BDUNCD) as the next generation electrode material for neurochemical sensor development. To aid in long-term chronic monitoring of neurochemicals, they have a wide window of electrochemical potential, extremely low background current, and excellent chemical inertness. The main research goal is to reduce the rate of electrode fouling due to the reaction by-products, and significantly extend their useful lifetime.

We systematically characterize …

Porphyrinoids With Designed Properties, Michael P. Luciano

Doctoral Dissertations

This thesis focuses on the development of new synthetic methodologies toward porphyrinoids with properties designed for various applications. Among the chromophores studied are the quinoline‑annulated porphyrins, a relatively unexplored class of p-extended porphyrinoids that absorb light in the near-infrared region (NIR). Another class studied are the pyrrole-modified porphyrins (PMPs), (hydro)porphyrin analogues containing a non-pyrrolic building block.

The synthesis of chlorin and chlorin-analogues of the quinoline-annulated porphyrins are described that are characterized by even more red-shifted optical spectra than regular quinoline-annulated porphyrins (Chapter 2). The NIR-emitting platinum(II) complexes of the quinoline-annulated porphyrins suggest potential in vivo O₂ sensing …

Design And Fabrication Of High Performance Zno/Perovskite Nano-Array Based Monolithic Catalysts For Automotive Emission Control, Sibo Wang

Doctoral Dissertations

Monolithic catalyst, usually composed of honeycomb substrate and wash-coated powder-form catalysts on its channel surface, represents a unique class of functional devices that has been adapted in current industries, particularly in automotive industry as catalytic converters for engine emission aftertreatment purpose. The powder wash-coat based monolithic catalyst lacks well-defined structural configuration in particulate size, shape and distribution, leading to usually compromised materials utilization efficiency and catalytic activity. Thus, it is necessary to develop new generation of high performance monolithic catalysts to meet the increasingly stringent emission regulation. Perovskite materials have been studied as potential candidate of automotive catalysts for decades, …

Three Essays On Immigrants’ Socio-Economic Integration In The United States, Tao Song

Doctoral Dissertations

Using data from the U.S. censuses and American Community Surveys from 1950 to 2010, my dissertation investigates immigrants’ socio-economic integration in the U.S. I aim to study the causes and consequences of immigrants’ integration in the U.S. and to offer insights on policies that could facilitate immigrants in their assimilation process. The first chapter analyzes the increasing native-immigrant wage gaps since the 1980s. The second chapter studies the increasing wage premiums of intermarried immigrants since the 1980s. The third chapter studies why people live in ethnic enclaves.

I find that technological change and globalization, which have increased the relative price …

Jointly Learning Features And Temporal Contingency For Prediction In Large Scale Datasets, Tingyang Xu

Doctoral Dissertations

Temporal data such as time series data and longitudinal data are pervasive across almost all human endeavors, including medicine, finance, climate, and genetics. As such, it is hardly surprising that temporal data mining has attracted significant attention and research effort. Only very recently, feature selection has drawn adequate attention in the context of longitudinal modeling. Standard statistical techniques, such as generalized estimating equations (GEE), have been modified to identify important features by imposing sparsity-inducing regularizers. However, they do not explicitly model how a dependent variable relies on features measured at proximal time points. Recent machine learning models can select features …

Design, Synthesis And Characterization Of Advanced Nanomaterials For Environmental And Energy Applications, Mohammad S. Seraji

Doctoral Dissertations

The research work presented in this thesis is focused on design, synthesis, and characterization of transition metal oxide nanomaterials for environmental and energy applications. New synthetic techniques are designed and optimized for improved catalytic activity of the prepared materials over the conventional techniques. The nanomaterials were thoroughly characterized and used in various chemical reactions.

There are five chapters in this thesis. Chapter one provides background information and significance about four research projects presented in this thesis. Chapter two explains the catalyst design and single step synthesis of mesoporous sulfated zirconia using inverse micelle templated method for biodiesel production. This inverse …

Gold Nanoparticles And Quantum Dots: Their Optical Interaction And Application In A Hydrogel Modified Lateral Flow Sensing Device, Julie A. Jenkins

Doctoral Dissertations

The goal of this dissertation was to study the optical properties of gold nanoparticles (Au NP) and quantum dots (QD) and to use their unique properties in sensing applications. The first part of this dissertation focuses on studying the dipole coupling in a gold nanoparticle random array. A blue shift and narrowing of the extinction peak, when compared to the single particle and solution spectra, was observed when 120 nm Au NPs were randomly immobilized on a glass substrate. This was determined to be due to the long-range dipole coupling of the Au NPs in the array. The motivation behind …

Telling Tales: Narrative And Anti-Narrative Approaches In British Chamber Music, 1900-1930, Sacha Peiser

Doctoral Dissertations

The aim of this dissertation is to apply a narrative analytical lens to selected cyclic British chamber music compositions from the early part of the twentieth century: Ralph Vaughan Williams’ Piano Quintet in C Minor (1903) and Phantasy Quintet (1912); Rebecca Clarke’s Piano Trio (1921); and Frank Bridge’s String Quartet No. 3 (1927). This narrative reading will examine both micro- and macroscopic elements of the selected works, including large-scale formal structures, thematic recurrence and transformation, motivic manipulation, and pitch-class conflict.

Chapter One contextualizes these works with respect to the musical, educational, and compositional culture of the English Musical Renaissance. Chapter …

Uas Collision Warning And Passive Sensor Fusion Algorithms For Multiple Acoustic Transient Emitter Localization, Wenbo Dou

Doctoral Dissertations

This dissertation considers two important topics in the area of estimation, target tracking and sensor fusion. The first topic is closest point of approach (CPA) prediction for unmanned aircraft systems (UAS) collision warning and the second topic is passive sensor fusion for multiple acoustic transient emitter localization.

To operate within a controlled airspace, UAS must have the capability to sense and avoid collisions with non-cooperative aircraft. This dissertation presents an inexpensive system design and develops an algorithm for estimating the CPA between the ownship and the intruder and a collision warning scheme using only bistatic range and range rate measurements …

Combined Intrinsic Caloric Effects In Ferroelectrics, Hamidreza Khassaf

Doctoral Dissertations

There exist multiple driving forces in solid–state materials that can be utilized for entropy changes and hence stronger caloric response. In multiferroic materials, adiabatic temperature changes (ΔT_ad) can be obtained via combined application of electric, stress, and magnetic fields. These external stimuli provide additional channels of entropy variations resulting in a multi–caloric response. In ferroelectric (FE) materials, caloric responses can be obtained with the application of electric and mechanical fields. Here, we compute the intrinsic electrocaloric and elastocaloric of prototypical FE materials using Landau–Devonshire theory of phase transformations with appropriate electrical and electro–mechanical boundary conditions. Also, the …

Rational Design Of Polymer Dielectrics Using First Principles Computations And Machine Learning, Arun Kumar Mannodi Kanakkithodi

Doctoral Dissertations

While intuition-driven experiments and serendipity have guided traditional materials discovery, computational strategies have become increasingly prevalent and a powerful complement to experiments in modern day materials research. A novel approach for efficient materials design is “rational co-design”, where high-throughput computational screening is used synergistically with experimental synthesis and testing. In this Thesis, the utility and promise of such an approach was demonstrated for the design of advanced polymer dielectrics for electrostatic energy storage applications. Density functional theory computations were applied to study the structural, electronic and dielectric properties of polymers, based on which targeted synthesis and property measurements were carried …

Formal Modeling And Mining Of Big Data, Aljoharah A. Algwaiz

Doctoral Dissertations

As data collection technologies are advancing and memory storage costs are declining, volumes of data collected have soared. Scientists and investigators are collecting all possible data in fear of missing out on important information. With the merge of the data collection trend, researchers were studying data mining and analysis to find the most efficient way to data mine. There are various valuable data mining techniques that can be found in literature such as Support Vector Machine (SVM), Neural Networks (ANN), and Formal Methods (Grammars). Grammars are a very valuable in analyzing structured data and describing them in a condense matter. …

Tumor Hypoxia Targeted Fluorescence Imaging And Chest-Wall-Effect Reducing In Ultrasound-Guided Diffuse Optical Tomography, Feifei Zhou

Doctoral Dissertations

Targeting tumor hypoxia has a profound impact in assessing anti-cancer treatments. Previously we reported the use of 2-nitroimidazole and indocyanine green conjugate (2-nitroimidazole-ICG) to target tumor hypoxia in in vivo tumor models. In this study, we evaluated a new generation hypoxia-targeted rigid dye that has a higher fluorescence yield. Results show that it has ~100 nm absorption/emission wavelengths shift and 3-4 times fluorescence quantum yield comparing with 2-nitroimidazole-ICG, as well as more than twice in vivo tumor fluorescence intensity. These initial results suggest that the targeted rigid dye may significantly improve in vivo tumor hypoxia targeting.

We have developed ultrasound …

Equilibrium And Kinetically-Limited Lattice Relaxation Of Multilayered And Compositionally-Graded Semiconductor Metamorphic Heterostructures, Tedi Kujofsa

Doctoral Dissertations

Metamorphic buffer layers (MBLs) allow tremendous flexibility in designing novel semiconductor heterostructures for application in various microelectronic and optical devices. However, device fabrication, reliability and performance are limited by lattice relaxation mechanisms and dislocation defects that are associated with the growth of mismatched material systems. Therefore, understanding the extent of strain relaxation and dislocation dynamics in semiconducting heterostructures has important implications in the design of devices which exhibit desired strain and dislocation characteristics. In this dissertation, we present equilibrium and plastic flow models which are applicable to multilayered and compositionally-graded semiconductor heterostructures and have studied both the thermal equilibrium and …

Novel Algorithms For Big Data Analytics, Subrata Saha

Doctoral Dissertations

In this dissertation we offer novel algorithms for big data analytics. We live in a period when voluminous datasets get generated in every walk of life. It is essential to develop novel algorithms to analyze these and extract useful information. In this thesis we present generic data analytics algorithms and demonstrate their applications in various domains.

A number of fundamental problems, such as clustering, data reduction, classification, feature selection, closest pair detection, data compression, sequence assembly, error correction, metagenomic phylogenetic clustering, etc. arise in big data analytics. We have worked on some of these fundamental problems and developed algorithms that …