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Pled Enhancement And Re-Use, Carlos A. Ayala

Master's Theses

Polymer light emitting diodes (PLEDs) represent new technology for display applications. However, these polymer based devices could benefit from increased efficiency and material longevity.

This thesis examines how preprocessing PLED indium tin oxide (ITO) anodes and reprocessing previously used substrates can create brighter, more efficient PLEDs. The project accomplishes this by simple changes to fabrication techniques, such as additional cleaning, etching, or thermal annealing, to improve pristine device luminance and efficiency. The project also examines substrate re-use techniques to repair ITO substrate damage, and effects of polymer aging on PLED luminance and efficiency.

PLEDs fabricated with polymer aged to varying …

Static And Fatigue Failure Response Of Woven Carbon Fiber Specimens With Double Edge Notches, Ahmad J. Amini

Master's Theses

Carbon fiber composites are continually seeing increased use in aerospace applications. It is necessary to understand their failure modes in order to properly design and perform analysis on structures constructed primarily from them. This thesis studies woven carbon fiber composites with and without double-edge notches in a series of static and fatigue tests performed on an Instron 8801 servo-hydraulic testing system.

Specimens were constructed of Advanced Composites Group product # LTM45EL woven carbon fiber pre-preg/epoxy and were cut to approximately 9-inch in length and 1-inch in width. Notches were cut into some of the specimens using a slitting saw blade …

Unmanned Aerial Vehicles For Post Disaster Surveys, Thor Liland Larsen

Master's Theses

In the current built environment, structures require regular observation and maintenance. Many of these structures can be quite challenging to evaluate. The required scaffolding, lifts, or similar access facilities can become quite costly to rent and construct, and can be a long term disturbance to those who use and manage the particular structure. Furthermore, there are situations where examination for the purpose of detailed analysis can be quite hazardous, if not entirely unsafe for humans. In a post-disaster environment traditional methods may not be safe or adequate for gaining access to parts of a structure that require observation or analysis. …

Effects Of Cloud-Induced Photovoltaic Power Transients On Power System Protection, Joel A. Nelson

Master's Theses

As the world strives towards finding alternative sources of power generation, photovoltaic generation has become an increasingly prevalent alternative energy source on power systems world-wide. This paper studies the effects that incorporating photovoltaic generation has on the existing power systems and their power system protection schemes. Along with the addition of this emerging alternative energy source comes the volatility of PV power generation as cloud-cover produces erratic variations in solar irradiance and PV power production. Such variations in PV power may lead to unfavorable operating conditions and power system failures. The issues addressed in this paper include a study of …

Assessment Of Morphology And Hemodynamics In Normal And Remodeled Microvasculature With Parameter Sensitivity Analysis, Shilpi Ghosh

Master's Theses

The goal of this study was to compare the morphological and hemodynamic characteristics of normal and remodeled vascular networks in the mouse gracilis muscle. To this end, previously developed models to assess flows and vascular branching were used to assess the normal and remodeled microcirculatory networks. The analysis revealed that the average individual vessel flow rates for vessels of similar caliber and total volumetric flow rates in the networks do not change for vessels of the same caliber after remodeling. Connectivity changes and average diameters primarily change in the larger arterioles after remodeling. A few correlations could be made between …

Anaerobic Co-Digestion Of Wastewater Treatment Pond Algae With Wastewater Sludge, Daniel Eric Heimel

Master's Theses

Microalgae harvested from wastewater treatment ponds can be anaerobically digested to produce biogas, a renewable fuel resource. However, past experiments have shown some limitations of algae digestion. Algal cell walls are thought to be resistant to digestion, and the high protein content of algae can lead to ammonia toxicity in digesters. Co-digestion of algae with substrates containing higher C:N ratios (e.g., waste paper) can be used to maintain non-inhibitory ammonia concentrations and increase methane production. However, high carbon waste co-substrates have become costly or are not readily available in many communities. Although domestic wastewater sludge has only a marginally higher …

Three Algorithms For Causal Learning, Roshan Ram Rammohan

Computer Science ETDs

The field of causal learning has grown in the past decade, establishing itself as a major focus in artificial intelligence research. Traditionally, approaches to causal learning are split into two areas. One area involves the learning of structures from observational data alone and the second, involves the methodologies of conducting and learning from experiments. In this dissertation, I investigate three different aspects of causal learning, all of which are based on the causal Bayesian network framework. Constraint based structure search algorithms that learn partially directed acyclic graphs as causal models from observational data rely on the faithfulness assumption, which is …

Regulation Of Biofilm And Antibiotic-Resistance By The Modulator Of Sara (Msa) In Staphylococcus Aureus, Antony Schwartz

Dissertations

Staphylococcus aureus is an important human pathogen that is the causative agent of life-threatening diseases such as endocarditis and osteomyelitis. The ability of S. aureus to thrive as a successful pathogen can be partially attributed to its ability to form biofilm. Biofilm is an extracellular polysaccharide, protein, and DNA-based slime layer that protects the bacterial community. The global regulator sarA is essential for biofilm formation. Since the modulator of sarA (msa) gene regulates several virulence factors and is required for the full expression of sarA, the capacity of the msa mutant to form a biofilm was examined. The mutation of …

Bemdec: An Adaptive And Robust Methodology For Digital Image Feature Extraction, Isaac Kueth Gang

Dissertations

The intriguing study of feature extraction, and edge detection in particular, has, as a result of the increased use of imagery, drawn even more attention not just from the field of computer science but also from a variety of scientific fields. However, various challenges surrounding the formulation of feature extraction operator, particularly of edges, which is capable of satisfying the necessary properties of low probability of error (i.e., failure of marking true edges), accuracy, and consistent response to a single edge, continue to persist. Moreover, it should be pointed out that most of the work in the area of feature …

A Comprehensive Uncertainty Analysis And Method Of Geometric Calibration For A Circular Scanning Airborne Lidar, Michael Oliver Gonsalves

Dissertations

This dissertation describes an automated technique for ascertaining the values of the geometric calibration parameters of an airborne lidar. A least squares approach is employed that adjusts the point cloud to a single planar surface which could be either a narrow airport runway or a dynamic sea surface. Going beyond the customary three boresight angles, the proposed adjustment can determine up to eleven calibration parameters to a precision that renders a negligible contribution to the point cloud’s positional uncertainty.

Presently under development is the Coastal Zone Mapping and Imaging Lidar (CZMIL), which, unlike most contemporary systems that use oscillating mirrors …

Design And Development Of Intelligent Navigation Control Systems For Autonomous Robots That Uses Neural Networks And Fuzzy Logic Techniques And Fpga For Its Implementation, Christopher James Jeanniton

College of Graduate Studies: Theses & Dissertations

This research compares the behavior of three robot navigation controllers namely: PID, Artificial Neural Networks (ANN), and Fuzzy Logic (FL), that are used to control the same autonomous mobile robot platform navigating a real unknown indoor environment that contains simple geometric-shaped static objects to reach a goal in an unspecified location. In particular, the study presents and compares the design, simulation, hardware implementation, and testing of these controllers. The first controller is a traditional linear PID controller, and the other two are intelligent non-linear controllers, one using Artificial Neural Networks and the other using Fuzzy Logic Techniques. Each controller is …

Effective School District Recruitment Strategies Of African American Teachers, Christopher P. Watkins

College of Graduate Studies: Theses & Dissertations

There has been a continual decline in the number of available minority group teachers to supply America's public school for the past six decades. Several factors were noted for this decline which included better opportunities for minority advancement in other professions, low teacher salaries, the low prestige and status of teaching, institutional racism, and challenges with teacher certification and state licensure exams. The purpose of this study was to identify strategies used by school district officials to increase African American teacher hiring in Georgia. This study examined the district strategies that were implemented to recruit and hire minority teachers and …

Global Positioning System, Vladimir Villalba

Electrical Engineering

The Global Positioning System (GPS) is a navigation network consisting of 24 satellites in orbit around the Earth. This satellite system provides the accurate position of an individual in all weather conditions at all times around the world. Individuals can use GPS receivers to locate where they are, pinpoint where they want to go with any form of transportation.

The senior project embarks in a path to understand the workings of the GPS satellite system. To accomplish this task, the concepts learned in Electrical Engineering will be implemented. This report encompasses the design process and steps taken in prototyping a …

Progressivism And The Executive Branch: Woodrow Wilson's Expansion Of Presidential Power, Christopher F. Fisher

Pell Scholars and Senior Theses

This paper examines how and to what degree Woodrow Wilson expanded the power of the president. After the Civil War, immigration, urbanization, and industrialization changed America. Progressives like Wilson argued that many of these changes were harmful to society. Wilson argued that a president with an expanded role, supplemented by administrative bureaucracies, could solve what Progressives believed were the problems of capitalism and the Founder's vision of America.

Physical Activity: The Future Of Learning?, Michael W. Beets, Amanda E. Paluch, Edward C. Archer, Steven N. Blair

Faculty Publications

No abstract provided.

Analysis Of Nitrogen Loading Reductions For Wastewater Treatment Facilities And Non-Point Sources In The Great Bay Estuary Watershed, Philip Trowbridge, Thomas S. Burack, Michael J. Walls, Harry T. Stewart

PREP Reports & Publications

In 2009, the New Hampshire Department of Environmental Services (DES) published a proposal for numeric nutrient criteria for the Great Bay Estuary. The report found that total nitrogen concentrations in most of the estuary needed to be less than 0.3 mg N/L to prevent loss of eelgrass habitat and less than 0.45 mg N/L to prevent occurrences of low dissolved oxygen. Based on these criteria and an analysis of a compilation of data from at least seven different sources, DES concluded that 11 of the 18 subestuaries in the Great Bay Estuary were impaired for nitrogen. Under the Clean Water …

How Communist Is North Korea?: From The Birth To The Death Of Marxist Ideas Of Human Rights, Jiyoung Song

Research Collection School of Social Sciences

This article focuses on the Marxist characteristics of North Korea in its interpretation of human rights. The author's main argument is that many Marxist features pre-existed in Korea. Complying with Marxist orthodoxy, North Korea is fundamentally hostile to the notion of human rights in capitalist society, which existed in the pre-modern Donghak (Eastern Learning) ideology. Rights are strictly contingent upon one's class status in North Korea. However, the peasants' rebellion in pre-modern Korea was based on class consciousness against the ruling class. The supremacy of collective interests sees individual claims for human rights as selfish egoism, which was prevalent in …

Economic Impact Of The University Of Texas‐Pan American, University Of Texas-Pan American

UTPA Archives - Stats At A Glance

This study was conducted to determine the economic and social impacts of The University of Texas-Pan American (UTPA) on McAllen-Edinburg-Mission Metropolitan Statistical Area’s (MSA) economy.

Seismic Anisotropy Beneath The Afar Depression And Adjacent Areas: Implications For Mantle Flow, Stephen S. Gao, Kelly H. Liu, Mohammed G. Abdel Salam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Shear wave splitting is a robust tool to infer the direction and strength of seismic anisotropy in the lithosphere and underlying asthenosphere. Previous shear wave splitting studies in the Afar Depression and adjacent areas concluded that either Precambrian sutures or vertical magmatic dikes are mostly responsible for the observed anisotropy. Here we report results of a systematic analysis of teleseismic shear wave splitting using all the available broadband seismic data recorded in the Afar Depression, Main Ethiopian Rift (MER), and Ethiopian Plateau. We found that while the ~450 measurements on the Ethiopian Plateau and in the MER show insignificant azimuthal …

Geophysics At The Interface: Response Of Geophysical Properties To Solid-Fluid, Fluid-Fluid, And Solid-Solid Interfaces, Rosemary Knight, Laura J. Pyrak-Nolte, Lee D. Slater, Estella A. Atekwana, Anthony L. Endres, Jil T. Geller, David P. Lesmes, Seiji Nakagawa, Andre Revil, Mukul M. Sharma, Christian Straley

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Laboratory studies reveal the sensitivity of measured geophysical properties to solid-fluid, fluid-fluid, and solid-solid interfaces in granular and fractured materials. In granular materials, electrical properties and nuclear magnetic resonance relaxation times exhibit a strong dependence on the size and properties of the solid-fluid interface. The electrical and seismic properties of granular materials and the seismic properties of fractured materials reveal a dependence on the size or geometry of fluid-fluid interfaces. Seismic properties of granular and fractured materials are affected by the effective stress and cementing material at solid-solid interfaces. There have been some recent studies demonstrating the use of field-scale …

Elucidating Functional Roles For Myogenin In Adult Skeletal Muscle Metabolism, Exercise Capacity, And Regeneration, Jesse Flynn

Dissertations and Theses (Open Access)

The four basic helix-loop-helix myogenic transcription factors, myogenin, Myf5, MRF4, and MyoD are critical for embryonic skeletal muscle development. Myogenin is necessary for the terminal differentiation of myoblasts into myofibers during embryogenesis, but little is known about the roles played by myogenin in adult skeletal muscle function and metabolism. Furthermore, while metabolism is a well-studied physiological process, how it is regulated at the transcriptional level remains poorly understood. In this study, my aim was to determine the function of myogenin in adult skeletal muscle metabolism, exercise capacity, and regeneration. To investigate this, I utilized a mouse strain harboring the Myogflox …

The Immune Inhibitor A1 Protease Of Bacillus Anthracis, Kathryn Pflughoeft

Dissertations and Theses (Open Access)

Bacillus anthracis, an organism ubiquitous in the soil and the causative agent of anthrax, utilizes multiple mechanisms to regulate secreted factors; one example is the activity of secreted proteases. One of the most abundant proteins in the culture supernates of B. anthracis is the Immune Inhibitor A1 (InhA1) protease. Here, I demonstrate that InhA1 modulates the abundance of approximately half of the proteins secreted into the culture supernates, including substrates that are known to contribute to the ability of the organism to cause virulence. For example, InhA1 cleaves the anthrax toxin proteins, PA, LF, and EF. InhA1 also targets …

The Role Of Post-Translation Regulation Of Twist Expression In The Tumor Progression Of Squamous Cell Carcinoma Of Head And Neck, Ying-Wen Su

Dissertations and Theses (Open Access)

Squamous cell carcinoma of head and neck (SCCHN) is the tenth most common cancer in the world. Unfortunately, the survival of patients with SCCHN has not improved in the last 40 years. Therefore new targets for therapy are needed, and to this end we are studying signaling pathways activated by IL-6 which we have found stimulates cell migration and soft agar growth in SCCHN. Our data show that IL-6 increases TWIST expression in a transcription-independent mechanism in many SCCHN cell lines. Further investigation reveals TWIST can be phosphorylated upon IL-6 treatment. By computation prediction (http://scansite.mit.edu/motifscan_seq.phtml ), we found that TWIST …

Agrobacterium Virb10 Contributions To Type Iv Substrate Secretion, T-Pilus Biogenesis, And Outer Membrane Pore Formation, Isaac Garza

Dissertations and Theses (Open Access)

The VirB/D4 type IV secretion system (T4SS) of Agrobacterium tumefaciens functions to transfer substrates to infected plant cells through assembly of a translocation channel and a surface structure termed a T-pilus. This thesis is focused on identifying contributions of VirB10 to substrate transfer and T-pilus formation through a mutational analysis. VirB10 is a bitopic protein with several domains, including a: (i) cytoplasmic N-terminus, (ii) single transmembrane (TM) α-helix, (iii) proline-rich region (PRR), and (iv) large C-terminal modified β-barrel. I introduced cysteine insertion and substitution mutations throughout the length of VirB10 in order to: (i) test a predicted transmembrane topology, (ii) …

4-H Leaders: Factors That Affect Their Persistence In The 4-H Youth Development Program, Regina Schinker

Dissertations

For over one hundred years, the 4-H youth development program has educated millions of children across the country in a variety of programs; from livestock husbandry to leadership skills. Like all programs that have endured, 4-H has had to adjust its focus as society has changed. One area in the 4-H program that has not changed is the heavy reliance on adult volunteer leaders to deliver the educational programs to 4-H youth. Because of the reliance on volunteer 4-H leaders, 4-H professionals and extension office staff are concerned about issues of retention.

The case study examines two related issues: First, …

Debugging Techniques For Locating Defects In Software Architectures, Kyungsoo Im

All Dissertations

The explicit design of the architecture for a software product is a well established part of development projects. As the software architecture descriptions are becoming larger and more complex, there is more likelihood of defects being present in the software architecture. Studies have shown that a defect in the software architecture that has propagated to the development phase is very expensive to fix. To prevent such propagation of defects, this research proposes to provide debugging support for software architecture design.
Debugging is commonly used in programming languages to effectively find the cause of a failure and locate the error to …

An Investigation Of Metaheuristics Using Path- Relinking On The Quadratic Assignment Problem, Thashika Rupasinghe

All Dissertations

The Quadratic Assignment Problem (QAP) is a widely researched, yet complex, combinatorial optimization problem that is applicable in modeling many real-world problems. Specifically, many optimization problems are formulated as QAPs. To resolve QAPs, the recent trends have been to use metaheuristics rather than exact or heuristic methods, and many researchers have found that the use of hybrid metaheuristics is actually more effective. A newly proposed hybrid metaheuristic is path relinking (PR), which is used to generate solutions by combining two or more reference solutions. In this dissertation, we investigated these diversification and intensification mechanisms using QAP. To satisfy the extensive …

Packet Error Rate Predictive Model For Sensor Radios On Fast Rotating Structures, Lei Tang

All Dissertations

Wireless sensing technologies have raised widespread interests in the applications for monitoring fast rotating or moving machinery structures in manufacturing environments. Over the past five years, a few wireless sensor systems have been implemented and proven to feasibly work under fast rotation conditions. However, few of these studies evaluated data transmission performance of the wireless communication systems. Although the manufacturing environments are known to be harsh for wireless communication, in many cases, an excellent data throughput is critical for such systems. Conventional statistical methods for studying wireless communication channels are not sufficient in this specific field.
This dissertation presents systematic …

Deadly Discourse: Negotiating Bureaucratic Consensus For The Final Solution Through Organizational And Technical Communication, Mark Ward Sr

All Dissertations

The Final Solution was largely accomplished in eleven months; its executors, the Nazi SS, faced the constant problem that as killing and plunder escalated so did internal competition and corruption; and the SS deliberately cultivated an intensely competitive and polycratic organizational culture that fit the Nazi worldview of life-as-struggle. By tying these three observations together—that the Final Solution was punctuated, entropic, and polycratic—the problem arises: How did SS organizational communications manage, just barely long enough, to create a temporary social reality that regulated the internal contradictions of its genocidal project and fragmented bureaucracy? This study contends that through its organizational …

Predictive Energy Management In Connected Vehicles: Utilizing Route Information Preview For Energy Saving, Chen Zhang

All Dissertations

This dissertation formulates algorithms that use preview information of road terrain and traffic flow for reducing energy use and emissions of modern vehicles with conventional or hybrid powertrains. Energy crisis, long term energy deficit, and more restrictive environmental protection policies require developing more efficient and cleaner vehicle powertrain systems. An alternative to making advanced technology engines or electrifying the vehicle powertrain is utilizing ambient terrain and traffic information in the energy management of vehicles, a topic which has not been emphasized in the past. Today's advances in vehicular telematics and advances in GIS (Geographic Information System), GPS (Global Positioning Systems), …