Digital Commons Network^™

Real Options Modeling And Valuation Of Price Adjustment Flexibility With An Application To The Leasing Industry, Ahmed A. A. Al Sharif

Doctoral Dissertations

"Uncertainty poses not only threats but also opportunities. This study sought to build the scientific foundation for introducing a real options (ROs) methodology for price risk management to the leasing industry. A price risk management that allows for both coping with threats and taking advantage of opportunities. In the leasing industry, fixed rate long-term lease contracts help contract parties stabilize cash flows within volatile markets. The contract's term, however, may be extended long enough that prevent capturing the opportunities of gaining greater profits or reducing expenses. Therefore, the flexibility that enables participants to take advantage of favorable market price is …

Data Fusion Techniques For Nondestructive Evaluation And Medical Image Analysis, Soumya De

Doctoral Dissertations

"Data fusion is a technique for combining data obtained from multiple sources for an enhanced detection or decision. Fusion of data can be done at the raw-data level, feature level or decision level. Applications of data fusion include defense (such as battlefield surveillance and autonomous vehicle control), medical diagnosis and structural health monitoring. Techniques for data fusion have been drawn from areas such as statistics, image processing, pattern recognition and computational intelligence. This dissertation includes investigation and development of methods to perform data fusion for nondestructive evaluation (NDE) and medical imaging applications. The general framework for these applications includes region-of-interest …

Establishing Well Operability Limits For Frac Pack Sandface Well Completions Using A Screen Erosion Model And Well Completion Score Card, Rickey Hendrix

Doctoral Dissertations

"Completion quality has a direct impact upon the maximum production rate at which a frac pack well should be operated. Best practices for frac pack well completions ensure the highest possible quality for the well completion. A novel frac pack well completion score card was developed based on best practices for frac pack well completions identified through consultation with industry experts. The score card systematically combines and assesses completions data readily available standard completion reports. The outcome of the score card process is a numerical completion quality rating, which combines all well design and frac pack operations information.

The completion …

Polarization And Opinion Analysis In An Online Argumentation System For Collaborative Decision Support, Ravi Santosh Arvapally

Doctoral Dissertations

"Argumentation is an important process in a collaborative decision making environment. Argumentation from a large number of stakeholders often produces a large argumentation tree. It is challenging to comprehend such an argumentation tree without intelligent analysis tools. Also, limited decision support is provided for its analysis by the existing argumentation systems. In an argumentation process, stakeholders tend to polarize on their opinions, and form polarization groups. Each group is usually led by a group leader. Polarization groups often overlap and a stakeholder is a member of multiple polarization groups. Identifying polarization groups and quantifying a stakeholder's degree of membership in …

Dynamic Modeling, Stability Analysis, And Controller Design For Dc Distribution Systems, Reza Ahmadi

Doctoral Dissertations

"The dc distribution systems or dc microgrids are known to be best suited for integration of renewable energy sources into the current power grid and are considered to be the key enabling technology for the development of future smart grid. Dc microgrids also benefit from better current capabilities of dc power lines, better short circuit protection, and transformer-less conversion of voltage levels, which result in higher efficiency, flexibility, and lower cost. While the idea of using a dc microgrid to interface distributed energy sources and modern loads to the power grid seems appealing at first, several issues must be addressed …

Geochemical And Isotopic Characterization Of Lead In Fugitive Dust From Unsurfaced Roads In Missouri, Emitt C. Witt

Doctoral Dissertations

"Eighteen unsurfaced roadways in Missouri's rural Ozark region were sampled to characterize the differences in trace element and isotopic chemistry to determine if there is a human health concern with inhaling and/or ingestion of fugitive dust generated by a moving vehicle. Road reaches were selected to represent those in similar rural areas with and without the presence of mining activity--13 roads were selected in the Viburnum Trend (VT) resource mining area and five were located to the southwest of the mining areas. Samples were collected using a novel cyclonic fugitive dust sampler (patent pending) that collects a composite sample from …

Numerical Modeling Of Heat Transfer And Fluid Flow In Laser Metal Deposition By Powder Injection, Zhiqiang Fan

Doctoral Dissertations

"Laser metal deposition is an additive manufacturing technique which allows quick fabrication of fully-dense metallic components directly from Computer Aided Design (CAD) solid models. A self-consistent three-dimensional model was developed for the laser metal deposition process by powder injection, which simulates heat transfer, phase changes, and fluid flow in the melt pool, The governing equations for solid, liquid and gas phases in the calculation domain have been formulated using the continuum model. The free surface in the melt pool has been tracked by the Volume of Fluid (VOF) method, while the VOF transport equation was solved using the Piecewise Linear …

Electronic Portfolios As Living Portals: A Narrative Inquiry Into College Student Learning, Identity, And Assessment, Celeste Fowles Nguyen

Doctoral Dissertations

As universities increasingly utilize electronic portfolios, college students are asked more than ever to create ePortfolios for academics, assessment, or advising. This study shifts an analysis of ePortfolios from prior epistemological approaches, where ePortfolios have been explored as a tool to measure student progress, onto an ontological perspective, where they are a medium for new understandings about self and others. This research examines the influence of college students' electronic portfolios on learning, identity, and assessment. The broader intention of this study is to create a narrative of students' experiences with ePortfolios that integrates critical hermeneutic theory.

The research protocol of …

Starting A Dialogue With Mexican Born Students: Appropriating A New Understanding In A Public High School, Vicne Leeburn

Doctoral Dissertations

Research Topic

This study uses the narratives of conversation participants to gain a new understanding of the issues faced by Mexican born students at Prospect High School, in the heart of Silicon Valley.

Research Theory and Protocol

Through critical hermeneutic theory formulated by Paul Ricoeur (1992) and the inquiry protocol developed by Ellen Herda (1999), I applied the interpretive categories of narrative identity, imagination and communicative action to this study.

Research Categories

The narratives describe the stories of the participants' experiences of coming to a new country and the difficulties and successes of assimilating into a new culture while still …

Asian American Women Leaders In The Pacific Coast: Their Pathway To Presidency In Two-Year Institutions, Joan Torne

Doctoral Dissertations

The field of education continues to see an underrepresentation of women as presidents of colleges and universities especially Asian Americans in general. In comparison with other racial and ethnic groups, Asian Americans are the only group not equally represented in high executive positions such as the presidential. In addition, women, including Asian American women, continue to hold, disproportionately to men, fewer leadership positions in the workplace of today.

It was the intent of this qualitative study to gain an understanding the reasons for the slow progress of Asian Americans in obtaining presidential positions in higher education with the focus on …

A Comparison Of Two Teaching Methods For Pediatric Medication Administration: Multimedia And Text-Based Modules, Renee Granados

Doctoral Dissertations

A Comparison of Two Teaching Methods for Pediatrics: Multimedia and Text-based Modules to Teach Pediatric Medication Administration

Nurse educators are in a position to design and develop effective methods that consider the cognitive structures and how the mind processes information to teach pediatric medication content to nursing students. The majority of methods teaching medication administration use only one mode: the visual mode. One mode to present leaning material does not take advantage of the additive effects of using two modes to present learning material.

The purpose of the study was to compare the effectiveness of two teaching methods to present …

Counter-Narratives Of La Raza Voices: An Exploration Of The Personal And Professional Lived Experiences Of Mexican-American/Chicana/O Faculty At California Catholic Institutions Of Higher Education, Frank Vincent Serrano

Doctoral Dissertations

Faculty members of color time and again encounter the greatest number of challenges and barriers (e.g., discrimination, isolation, marginalization, tokenism, inundated with workloads and service commitments, devalued research, and delayed promotion and tenure) in both entering academia and succeeding within academia.

The purpose of this study was to explore the personal and professional lived experiences of eight self-identified native-born Mexican-American and Chicana/o tenured and tenure-track faculty members employed at four California Catholic institutions of higher education.

This study utilized a qualitative narrative methodology employing the critical race tenets of counter-storytelling and the permanence of racism. Through use of this methodology, …

A Study Of Cellular Calcium Dynamics In Culture Using Fluorescence Microscopy – A Statistical And Mathematical Approach, Richard Adekola Idowu

Doctoral Dissertations

Calcium in its ionic form is very dynamic, especially in excitable cells such as muscle and brain cells, moving from the high concentration exterior of the cell to much lower concentrations inside the cell, where calcium is used as a second messenger. In brain cells, and neurons especially, calcium is a key signaling ion involved in memory and learning with excitatory neurotransmitters such as glutamate turning neurons "on." Glutamate excites the neurons in part by causing large and dynamic changes in the intracellular calcium concentration. While these dynamics are essential for normal signaling in the brain, excessive and sustained elevations …

Quantitation And Identification Of Protein S-Nitrosylation: Implication For The Progression Of Alzheimer's Disease, Siyang Wang

Doctoral Dissertations

Protein S-nitrosylation, the covalent modification of a cysteine sulfhydryl group by nitric oxide (NO), plays a critical role in post-translational modification (PTM) that regulates a large variety of cellular functions and signalling events. The nitrosylation state changes with oxidative damage and is involved in variety of cancers and neurodegeneration diseases.

Three technologies were developed for nitrosylated protein detection and identification. Capillary gel electrophoresis with laser induced fluorescence (CGE-LIF) detection was used for the detection and quantitation of nitrosylated proteins. A two-dimensional micro-electrophoresis (2D μ-CE) separations system was also built to detect nitrosylated proteins via poly (methylmethacrylate) microchips. Proteomics following nitrosylated …

Exploitation And Exploration Of Pcr In Microfluidic Systems With Gradient Temperature Environments, Ilija Pjescic

Doctoral Dissertations

The main goal of the work was to establish a wholesome picture off all relevant processes for a sample-in, answer out genetic system and to integrate the whole process on a one step device from sample collection to final result. The genetic analysis process consists of ideally three steps: sample preparation, chemical reaction, and analysis. Each of the steps is different and requires a specific environment, where sample preparation might use additives, they might later interfere with the reaction itself or lead to misleading results in the analysis phase. It was found to be quite a challenging process to synchronize …

The Contribution Of Oxidative Stress In The Protein Damage And Dna Lesion In Alzheimer's Disease Neuropathology, Cheng Zhang

Doctoral Dissertations

Glutathione (GSH) plays an essential role in the intracellular antioxidant defense against the oxidant radicals, especially the ·OH radical. To understand the early and progressive cellular changes in Alzheimer's disease (AD) development, we investigated reduced glutathione/oxidized glutathione (GSH/GSSG) status in a double mutated AD transgenic mouse model (B6.Cg-Tg), which carries Swedish amyloid precursor protein mutation (APPswe) and exon 9 deletion of the PSEN1 gene. Likewise, S-glutathionylation (Pr-SSG) is a specific post-translational modification (PTM) of cysteine residues by the addition of glutathione. S-glutathionylated proteins induced by oxidative stress play an essential role in understanding the pathogenesis of the aging …

A Novel Microfluidic Enrichment Technique For Carbonylated Proteins, Bryant C. Hollins

Doctoral Dissertations

Proteins are the building blocks of cells in living organisms, and are composed of amino acids. The expression of proteins is regulated by the processes of transcription and translation. Proteins undergo post-translational modifications in order to dictate their role physiologically within a cell.

Not all post-translational modifications are beneficial for the protein or the cell. One type of post-translational modification, called carbonylation, irreversibly places a carbonyl group onto an amino acid residue, most commonly proline, lysine, arginine, and threonine. This modification can have severe consequences physiologically, including loss of solubility, loss of function, and protein aggregation.

Carbonylated proteins have commonly …

Adaptive Grid Based Localized Learning For Multidimensional Data, Sheetal Saini

Doctoral Dissertations

Rapid advances in data-rich domains of science, technology, and business has amplified the computational challenges of "Big Data" synthesis necessary to slow the widening gap between the rate at which the data is being collected and analyzed for knowledge. This has led to the renewed need for efficient and accurate algorithms, framework, and algorithmic mechanisms essential for knowledge discovery, especially in the domains of clustering, classification, dimensionality reduction, feature ranking, and feature selection. However, data mining algorithms are frequently challenged by the sparseness due to the high dimensionality of the datasets in such domains which is particularly detrimental to the …

Oscillator-Based Neuronal Modeling For Seizure Progression Investigation And Seizure Control Strategy, Wu Chen

Doctoral Dissertations

The coupled oscillator model has previously been used for the simulation of neuronal activities in in vitro rat hippocampal slice seizure data and the evaluation of seizure suppression algorithms. Each model unit can be described as either an oscillator which can generate action potential spike trains without inputs, or a threshold-based unit. With the change of only one parameter, each unit can either be an oscillator or a threshold-based spiking unit. This would eliminate the need for a new set of equations for each type of unit. Previous analysis has suggested that long kernel duration and imbalance of inhibitory feedback …

A Hybrid Brain-Computer Interface Based On Motor Intention And Visual Working Memory, Ching-Chang Kuo

Doctoral Dissertations

Non-invasive electroencephalography (EEG) based brain-computer interface (BCI) is able to provide alternative means for people with disabilities to communicate with and control over external assistive devices. A hybrid BCI is designed and developed for following two types of system (control and monitor).

Our first goal is to create a signal decoding strategy that allows people with limited motor control to have more command over potential prosthetic devices. Eight healthy subjects were recruited to perform visual cues directed reaching tasks. Eye and motion artifacts were identified and removed to ensure that the subjects' visual fixation to the target locations would have …

Real-Time Analysis Of Brain Tumor Cell Dynamics: Novel Thermoelectric Detection Of L-Glutamate And Cell Metabolism Using Microfluidics, Siva Mahesh Tangutooru

Doctoral Dissertations

This study describes the design, fabrication and applications of a novel thermoelectric microfluidic bio-sensor. The bio-sensor is used for real time detection of the L-glutamate (L-glu) dynamics and metabolism for brain tumor cells immobilized in a microfluidic device. The microfluidic device is fabricated using a polymer/glass laminating technique (Xurography). An antimony-bismuth thin-film thermopile (primary sensing element) is integrated to the microfluidic device. The brain tumor cells are immobilized over the thermopile covering measuring and reference junctions of the thermopile using a poly-l-lysine coating layer. L-glutamate oxidase (L-GLOD) is immobilized over the measuring junctions of the thermopile prior to the immobilization …

Thermoelectric Effects In Self-Heating Silicon Microwires, Gokhan Bakan

Doctoral Dissertations

Self-heating mechanisms of small-scale structures have been an important subject where electrical and thermal transports are coupled, such as many electronic and optoelectronic devices, micro-electro-mechanical systems (MEMS), thermoelectric energy conversion devices and phase-change memory devices. In this work, nanocrystalline silicon microwires (L: 1 – 30 μm, Width: 0.1 – 1 μm, Thickness: 50 – 130 nm) are self-heated either through a single, short duration (< 1 μs) or longer DC/AC signal. The motivation behind this work is to melt the structures using electrical stress and to achieve larger crystalline domains (ultimately a single crystal domain) on the wires upon resolidification. Scanning electron micrographs show very smooth wire surfaces after the voltage pulse compared to as-fabricated nanocrystalline texture. Voltage-pulse induced self-heating leads to significant conductance improvement, suggesting crystallization of the wires. The minimum resistivity during the pulse extracted from wires of different dimensions matches previously reported values for liquid silicon. Hence, nanocrystalline silicon microwires melt through self-heating during the voltage pulse and resolidify upon termination of the pulse, resulting in very smooth and less-resistive crystalline structures.

Strong thermoelectric effects are observed on self-heated wires as asymmetric self-heating and melting of the wires when a microsecond voltage pulse is applied to melt only some portion (~ 50 %) of the wires. This …

Low Power Data Acquisition For Microimplant Biometric Monitoring Of Tremors, Tania Khanna '01

Doctoral Dissertations

In recent years, trends in the medical industry have created a growing demand for implantable medical devices. In particular, the need to provide doctors a means to continuously monitor biometrics over long time scales with increased precision is paramount to efficient healthcare. To make medical implants more attractive, there is a need to reduce their size and power consumption. Small medical implants would allow for less invasive procedures, greater comfort for patients, and increased patient compliance. Reductions in power consumption translate to longer battery life. The two primary limitations to the size of small medical implants are the batteries that …

Reliability Models For Hpc Applications And A Cloud Economic Model, Thanadech Thanakornworakij

Doctoral Dissertations

With the enormous number of computing resources in HPC and Cloud systems, failures become a major concern. Therefore, failure behaviors such as reliability, failure rate, and mean time to failure need to be understood to manage such a large system efficiently.

This dissertation makes three major contributions in HPC and Cloud studies. First, a reliability model with correlated failures in a k-node system for HPC applications is studied. This model is extended to improve accuracy by accounting for failure correlation. Marshall-Olkin Multivariate Weibull distribution is improved by excess life, conditional Weibull, to better estimate system reliability. Also, the univariate …

The Study Of Pt Dependence Of Dijet Azimuthal Decorrelations In Proton-Proton Collision At Center Of Mass Energy = 7 Tev, Ramasudhakar Dhullipudi

Doctoral Dissertations

The transverse momentum (pT) dependence of azimuthal decorrelations in dijet events is studied with data collected, at an integrated luminosity of [special characters omitted] dt = (36 ± 4) pb−1, from collisions between protons at a center of mass energy of [special characters omitted] = 7 TeV using the ATLAS detector at the Large Hadron Collider. The results of the analysis of jets in a central rapidity of |y| < 0.8 and pT in the range 60 GeV < pT < 1200 GeV are presented. A new observable RΔ&phis;, defined as the fraction of the total dijet cross section corresponding to a particular range of …

Study Of Jet Transverse Momentum And Jet Rapidity Dependence Of Dijet Azimuthal Decorrelations With The Dø Detector, Kiran Chakravarthula

Doctoral Dissertations

In a collision experiment involving highly energetic particles such as hadrons, processes at high momentum transfers can provide information useful for many studies involving Quantum Chromodynamics (QCD). One way of analyzing these interactions is through angular distributions. In hadron-hadron collisions, the angular distribution between the two leading jets with the largest transverse momentum (pT) is affected by the production of additional jets. While soft radiation causes small differences in the azimuthal angular distribution of the two leading jets produced in a collision event, additional hard jets produced in the event have more pronounced influence on the distribution of …

Event Shapes In Proton-Proton Collisions At Center Of Mass Energy = 1.96 Tev, Scott Atkins

Doctoral Dissertations

This dissertation presents the analysis of nine different event shapes measured in high energy pp¯ collisions. An event shape can be defined as an event-based quantity that measures how the final energies are distributed in the final event. This analysis will test strong interactions as described by Quantum Chromodynamics (QCD), through their implementation in different Monte Carlo-based models. Each of the event shapes provides information about the flow of energy in QCD events and about the hadronic final states that occur in pp¯ particle collisions, thus allowing the study of the dynamics of QCD multijet events. Any deviation of an …

Nanowire Giant Magnetoresistance Thin Films For Magnetic Sensors, Bryan Cox

Doctoral Dissertations

This dissertation details a novel method to fabricate magnetic sensors using nanowire giant magnetoresistance (GMR) thin films. In 1988, Albert Fert and Peter Grünberg both independently discovered a new physical phenomenon called GMR. GMR is a quantum mechanical effect found in thin film materials that are composed of alternating nanoscale ferromagnetic and non-magnetic conductive layers. When a GMR material is in the presence of a magnetic field, a change in electrical resistance is observed. The GMR effect has been utilized to produce magnetic sensors that have been used in a variety of applications, such as computer hard drive read heads, …

A Nanostructured Fabry-Perot Interferometer For Label-Free Biodetection, Tianhua Zhang

Doctoral Dissertations

A polymer nanostructured Fabry-Perot interferometer (FPI) based biosensor has been developed, fabricated, and tested. Different from a conventional FPI, this nanostructured FPI has a layer of Au-coated nanopores inside its cavity. The Au-coated nanostructure layer offers significant enhancement of optical transducing signals due to the localized surface Plasmon resonance (L-SPR) effect. Compared to a traditional FPI for label-free biosensing applications, the polymer nanostructured FPI based biosensor offers increased sensing surface area, extended penetration depth of the excitation light, and amplification of optical transducing signals. Using a nanostructured FPI, measurements taken had great improvements in free spectral range (FSR), finesse, and …

Numerical Simulation Of Nanopulse Penetration Of Biological Matter Using The Adi-Fdtd Method, Fei Zhu

Doctoral Dissertations

Nanopulses are ultra-wide-band (UWB) electromagnetic pulses with pulse duration of only a few nanoseconds and electric field amplitudes greater than 105 V/m. They have been widely used in the development of new technologies in the field of medicine. Therefore, the study of the nanopulse bioeffects is important to ensure the appropriate application with nanopulses in biomedical and biotechnological settings. The conventional finite-difference time-domain (FDTD) method for solving Maxwell's equations has been proven to be an effective method to solve the problems related to electromagnetism. However, its application is restricted by the Courant, Friedrichs, and Lewy (CFL) stability condition that confines …