Digital Commons Network^™

Iii-Nitride Semiconductors Grown By Plasma Assisted Molecular Beam Epitaxy, Lei He

Theses and Dissertations

III-nitride semiconductors are of great interest owing to their commercial and military applications due to their optoelectronic and mechanical properties. They have been synthesized successfully by many growth methods. Among them, molecular beam epitaxy (MBE) is a promising epitaxial growth method owing to precise control of growth parameters, which significantly affect the film properties, composition, and thickness. However, the understanding of growth mechanism of III-nitride materials grown in this growth regime is far from being complete.In this dissertation, GaN and AIGaN growth mechanism under metal-rich conditions were investigated. The Ga surface desorption behavior during the growth was investigated systematically using …

The Psychometric Properties Of The Inner Strength Questionnaire For Women With Chronic Health Conditions, Kristi Leanne Lewis

Theses and Dissertations

The purpose of this research was to develop and test an instrument to measure or quantify the construct of inner strength. Inner strength was synthesized into a theory based on twelve years of qualitative data from direct participant quotes, defined by Roux et al. (2002) as a central human resource that promotes well-being and healing. The inner strength questionnaire (ISQ) has undergone extensive psychometric evaluation which resulted in several versions. The third version had 37-items and was believed to have four subscales that mirrored the theoretical themes that emerged through the qualitative data. The sample was composed of 281 women …

Surface Characteristics Of Bacillus Spores, Darlene Danette Sabio

Theses and Dissertations

Rapid isolation and identification of spores from various environmental samples is necessitated because anthrax spores can be used as biological weapons. The hydrophobic nature of spores may allow for their rapid concentration and partial purification from contaminating materials. In this study, spores from four taxonomic groups of Bacillaceae were isolated, purified and characterized for hydrophobicity by hexadecane partitioning, surface morphology by scanning electron microscopy, and steady-state fluorescence by spectroscopy. The morphology of spores was similar within taxonomic groups and dissimilar between groups. Spore hydrophobicity ranged from 0.3% to 65% and all spores had fluorescence emission peaks at 335 nm and …

The Transformation Of Electricity In My Brain, Claire Watkins

Theses and Dissertations

This thesis is an exciting and enthralling story about the history of the world as seen through the eyes of Claire Watkins. The story takes place in the dusty corners of her art studio in the old confederate capital, Richmond, Virginia. Ms. Watkins leads her audience through such unsuspecting places as her brain, the life of an African Dung Beetle, the center of an atom and the dark reaches of outer space. The story is inspirational and thought provoking. It will force you to see the world as an interconnected web that weaves your life together with the cosmos. A …

Soul Hunting, Guido Esteban Alvarez

Theses and Dissertations

According to the Webster's unabridged dictionary, a mania is an excessively intense enthusiasm, interest, or desire; a craze. I experience a mania on a daily basis: I take photographs. I trap photographs inside flat, airless fish tanks where time stands still. The creatures captured inside the tanks resurrect every time I see them to remind me of a sound, an odor, a flavor, and, ultimately, a feeling I once experienced and now cherish. This project will attempt to show the energy captured in my photographic archives as a journey through my memories using an experimental interactive method.

Gas Phase Studies Of Molecular Clusters Containing Metal Cations, And The Ion Mobility Of Styrene Oligomers, Edreese Housni Alsharaeh

Theses and Dissertations

This study is divided into three parts. Part I deals with the mechanism of the self-initiated polymerization (or thermal polymerization) of styrene in the gas phase. In this work, we present the first direct evidence for the thermally self-initiated polymerization of styrene in the gas phase. Our approach is based on on-line analysis of the gas phase Oligomers by mass-selected ion mobility. The mobility measurements provide structural information on the ionized oligomers based on their collision cross-sections (Ω) which depend on the geometric shapes of the ions. Theoretical calculations of possible structural candidates of the Oligomers ions are then used …

Obesity And Health Status Among Urban Vs. Suburban Elderly In Philadelphia And Surrounding Counties, Ockidde Dufayne Harris

Theses and Dissertations

Obesity is a dangerous health condition affecting approximately 30% of all Americans and can be attributed to 300,000 deaths a year. Obesity has been found to disproportionately affect Blacks, Latinos, and those with lower SES. Although obesity is a problem for all age groups, its prevalence is highest among those 60-74 years of age. Studies have shown that there is an association between obesity and chronic conditions such as cardiovascular disease, arthritis, cancers, and type-2 diabetes. According to the Centers for Disease Control, chronic health conditions affect 80% of all elderly persons, many times limiting function and decreasing quality of …

Novel Apparatus To Control Electrospinning Fiber Orientation For The Production Of Tissue Engineering Scaffolds, Eugene David Boland

Theses and Dissertations

The conception of electrospinning can trace its roots back more than 400 years, when it was observed that rubbed amber can deform a droplet of water on a smooth surface, and is based upon simple concepts of charge separation and surface tension. Since that time, considerable effort has been directed at both the cause and utility of this phenomenon. The specific aim of this dissertation project was to develop an automated electrostatic processing apparatus that was capable of controlling the three-dimensional architecture of an electrospun scaffold to further improve its utility in tissue engineering. The efficacy of using this technique …

Rabies In Virginia, 1989-2003: With Particular Attention To Animals, Geographic Distribution, And Virus Variant, William Andrew Holzgrefe

Theses and Dissertations

Objectives: The description of the raccoon rabies epizootic in Virginia over fifteen years (1989-2003). Methods: Using simple statistical methods and a geographic information system (GIS)-based approach, and fifteen years worth of animal surveillance data, the progress of this epizootic has been charted in terms of the geographic spread of the disease, the major animal species affected by the disease and its spread, and the exposure and risk to humans and livestock animals presented by the expansion of the geographic range. Results: The resulting descriptive study illustrates the eastward expansion of the epizootic, the mushrooming of the disease in the northern …

Perpetual Novelty, Brian Caverly

Theses and Dissertations

Within this thesis is a mapping out of the processes, concepts, and influences, behind the sculptural practice of Brian Caverly. From Complex Adaptive Systems to the world of order of Michel Foucault to the reexamination of the Modernist movement by Yve Alain Bois and Rosalind Krauss, a rhizomatic path of connections and lines form and cross over, weaving together into a swarming mayhem of over population. Out of this chaos and order grow complex installations and constructions that are inherently bound by the system of their making, yet attempt at every turn to escape conformity.

Characterization Of Aligned Carbon Nanotube/Polymer Composites, Sumanth Banda

Theses and Dissertations

The main objective of this thesis is to efficiently disperse and align SWNTs in two different polymer matrices to obtain an orthotropic composite whose strength, stiffness and electrical properties depend on the orientation of the SWNTs. The SWNTs are successfully dispersed and aligned in a polyimide matrix and a polymer blend of UDMA/HDDMA. In-situ polymerization under sonication is used to disperse the SWNTs in polyimide matrix and sonication is used to disperse SWNTs in the UDMA/HDDMA matrix. In both cases, an electric field is used to align the SWNTs in the polymer matrices. In the polyimide, the SWNTs are aligned …

Effect Of Stochastic Dead Space On Noise In Avalanche Photodiodes, Oh-Hyun Kwon, Majeed M. Hayat, Joe C. Campbell, Bahaa E.A. Saleh, Malvin Carl Teich

Electrical and Computer Engineering Faculty Research and Publications

A stochastic dead-space model for impact ionization is developed and used to study the effect of the soft nature of the ionization capability of carriers on the excess noise factor of avalanche photodiodes. The proposed model is based on the rationale that the gradual, or soft, transition in the probability density function (PDF) for the distance from birth to impact ionization can be viewed as that resulting from uncertainty in the dead space itself. The resulting soft PDF, which is parameterized by a tunable softness parameter, is used to establish the limitations of the existing hard-threshold ionization models in ultrathin …

Effects Of Sputter Deposition Parameters On Stress In Tantalum Films With Applications To Chemical Mechanical Planarization Of Copper, Jeffrey L. Perry

Theses

Attempts to introduce a CMP process for copper damascene features at Rochester Institute of Technology were stymied by adhesion failures of the Ta/Cu film stack. This work was undertaken to investigate the effect of stress in the films on adhesion and to develop a viable CMP process for Cu damascene technology. In depth studies of stress as a function of sputter deposition conditions revealed that stress in Ta layers could vary from -1700 MPa compression to +800 MPa tensile for deposition pressures over a range of 2-20 mTorr for films having a nominal thickness of 0.25 μm. For a fixed …

The Wrong Way To Equality: Privileging Consent In The Trafficking Of Women For Sexual Exploitation, Beverly Balos

Articles

Chamoli lived near the birthplace of the Buddha in Nepal. When she was 16, she met a young man and fell in love with him. He promised to marry her but insisted that she come away with him to India. So one day she ran away with the boyfriend and crossed the border to India on foot. From there she and her boyfriend took a train to the Indian city of Poona. Once they had reached Poona, Chamoli was taken to a house where there was an older Nepali lady and many young girls. The lady gave her boyfriend some …

The Limits Of Business Limited Liability: Entity Veil Piercing And Successor Liability Doctrines, John Matheson

Articles

The quest for limited liability in business enterprises and transactions has been a driving force in the development of business organization law for centuries. The historical development of corporations and limited partnerships evidences this primary goal. The recent development of the modern forms of limited liability partnerships and limited liability companies proves that this quest continues unabated. In addition, parties to significant business transfer transactions have long sought by construct and contract to apportion and limit their respective legal responsibilities and liabilities.Counterbalancing this inexorable trend toward limited liability has been the penchant of common law jurisprudence to define its limits. …

Assessment Of Organic And Inorganic Pollutants In The Offshore Sediments, Dubai, Uae., Haifa Darwish Ahmad Al Darwish

Theses

The investigated area covers the maximum fragments of Dubai offshore in the Arabian Gulf. The sediment samples were collected from fifteen stations starting by Al-Mamzar mouth and ending by Ras Ghantoot in order to assess the organic and inorganic pollutants affecting the coastal region in Dubai.

The textural class was determined through grain-size analysis and the mineral composition was identified by X-Ray diffraction. The organic pollutants were characterized through the determination of Total Organic Carbon (TOC), Total Kjeldahl Nitrogen (TKN), Total Petroleum Hydrocarbons (TPH), Polycyclic Aromatic Hydrocarbons (PAHs), Polychlorinated biphenyls (PCBs) and individual polychlorinated biphenyls. On the other hand the …

Faith-Based Organizing And Partnerships In A Pittsburgh Neighborhood: A Look At East Liberty, Damon Bethea

Electronic Theses and Dissertations

The East Liberty neighborhood of Pittsburgh has a fascinating blend of African American churches and racially integrated churches -- all within this African American neighborhood in Pittsburgh's East End. In this research project, I will explore how several East Liberty churches are working with other churches (or faith-based organizations [FBOs]) and organizations within the East Liberty neighborhood to provide various social services to those within this predominantly African American community. The research questions for this project are: 1) How does the racial composition of the church community affect their relationship with the residents of East Liberty whom they serve? 2) …

Does Excessive Absence From Class Lead To Lower Levels Of Academic Achievement, Janet L. Faison

OTS Master's Level Projects & Papers

Based on this problem, the following hypothesis has been proposed: 1. Students who have higher records of absenteeism (absent four times or more during a given semester) will have lower academic achievement levels (GPA) while attending community college.

Does Participation In The Academic Continuance Experience For Success Program Increase Academic Achievement And Persistence Of Students Readmitted From Suspension, Norlisa Mayes

OTS Master's Level Projects & Papers

The purpose of this study was to determine if participation in an intervention program improved academic achievement and retention of at-risk college students at Old Dominion University.

Coalescence Remnant Of Spinning Binary Black Holes, J Baker, M. Campanelli, C. O. Lousto, R. Takahashi

Physics & Astronomy Faculty Publications

We compute the gravitational radiation generated in the evolution of a family of close binary black hole configurations, using a combination of numerical and perturbative approximation methods. We evolve the binaries with spins s aligned or counteraligned with the orbital angular momentum from near the innermost stable circular orbit down to the final single rotating black hole. For the moderately spinning holes studied here the remnant Kerr black holes formed at the end of an inspiral process have rotation parameters a/M≈0.72+0.32(s/mH), suggesting it is difficult (though not excluded) to end up with near maximally rotating holes from such scenarios.

Generation Of The Transient Electrical And Spontaneous Magnetic Fields By Solid State Combustion, Karen S. Martirosyan, J. R. Claycomb, J. H. Miller Jr., D. Luss

Physics & Astronomy Faculty Publications

Experiments revealed that transient electric field intensities up to 2.5 V/cm were generated during the initial period of combustion synthesis of the ferromagnetic products before the maximum temperature was reached. This occurred when the iron particles were partially oxidized and the reaction product was mainly magnetite sFe3O4d. The electromagnetic field caused spontaneous magnetization of the product in the postcombustion zone. Magnetic field values up to 4 µT formed after the sample temperature fell below the Curie temperature and the initial reactants were completely converted to the ferromagnetic phase PbFe12O19. Increasing the volume of the samples increases the absolute residual magnetic …

Setting Upper Limits On The Strength Of Periodic Gravitational Waves From Psr J1939+2134 Using The First Science Data From The Geo 600 And Ligo Detectors, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Joseph D. Romano, Cristina V. Torres

Physics & Astronomy Faculty Publications

Data collected by the GEO 600 and LIGO interferometric gravitational wave detectors during their first observational science run were searched for continuous gravitational waves from the pulsar J1939+2134 at twice its rotation frequency. Two independent analysis methods were used and are demonstrated in this paper: a frequency domain method and a time domain method. Both achieve consistent null results, placing new upper limits on the strength of the pulsar’s gravitational wave emission. A model emission mechanism is used to interpret the limits as a constraint on the pulsar’s equatorial ellipticity.

First Upper Limits From Ligo On Gravitational Wave Bursts, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Joseph D. Romano, Cristina V. Torres

Physics & Astronomy Faculty Publications

We report on a search for gravitational wave bursts using data from the first science run of the Laser Interferometer Gravitational Wave Observatory (LIGO) detectors. Our search focuses on bursts with durations ranging from 4 to 100 ms, and with significant power in the LIGO sensitivity band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than 1.6 events per day at a 90% confidence level. This result is interpreted in terms of the detection efficiency for ad hoc waveforms (Gaussians and sine Gaussians) as a function of their root-sum-square strain hrss; typical sensitivities …

Analysis Of Ligo Data For Gravitational Waves From Binary Neutron Stars, B. P. Abbott, R. Abbott, Wm. R. Johnston, Joseph D. Romano, V. Schmidt

Physics & Astronomy Faculty Publications

We report on a search for gravitational waves from coalescing compact binary systems in the Milky Way and the Magellanic Clouds. The analysis uses data taken by two of the three LIGO interferometers during the first LIGO science run and illustrates a method of setting upper limits on inspiral event rates using interferometer data. The analysis pipeline is described with particular attention to data selection and coincidence between the two interferometers. We establish an observational upper limit of R

Analysis Of First Ligo Science Data For Stochastic Gravitational Waves, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the analysis of between 50 and 100 h of coincident interferometric strain data used to search for and establish an upper limit on a stochastic background of gravitational radiation. These data come from the first LIGO science run, during which all three LIGO interferometers were operated over a 2-week period spanning August and September of 2002. The method of cross correlating the outputs of two interferometers is used for analysis. We describe in detail practical signal processing issues that arise when working with real data, and we establish an observational upper limit on a f−3 power spectrum of …

New Methods For Exafs Analysis In Structural Genomics, Grant Bunker, Nicholas Dimakis, Gocha Kelashvili

Physics & Astronomy Faculty Publications

Data analysis is one of the remaining bottlenecks in high-throughput EXAFS for structural genomics. Here some recent developments in methodology are described that offer the potential for rapid and automated XAS analysis of metalloproteins.

Residents' Attitudes And Perceptions Toward National Parks And Ecotourism Development In Ghana: The Case Of Dome Community In The Digya National Park, Paul Owusu Boi

Theses and Dissertations (Comprehensive)

The mode of park establishment generally conflicts with the use of natural resources as traditionally demanded by resident communities. These conflicts become compounded as a result of the process of land acquisition. Consequently, the process leads to formation of varied attitudes and perceptions that residents have towards national parks. The impacts of this attitude formation spread to any developments in the parks. There are many studies on attitudes of park residents toward tourism development in parks, however, only a few have examined attitudes and perceptions in the pre-development stage of tourism. This research uses a case study approach to examine …

An Evaluative Framework For Assessing Information Management In Watershed Management: The Case Of The Grand River Conservation Authority (Ontario), Robert Scott Brown

Theses and Dissertations (Comprehensive)

Watershed management has been rapidly evolving over the last 50 years. The current focus has been adaptive and ecosystem-based approaches to watershed management, redefining roles, responsibilities, and relationships of watershed organizations. While entire management models need to be heavily scrutinized, the practices and policies surrounding information are fundamentally important. Information forms the understanding and knowledge for watershed decision-making. Watershed organizations need to be critical of the policies and practices affecting their collection, storage, processing, analysis, monitoring, and reporting of data and information. Among the Conservation Authorities, the GRCA has developed a proficiency at information management, doing it as well as …

Forest Fires, Woodland Caribou And Land Use Policies In Northwestern Ontario (Rangifer Tarandus), Brian Frederick Kutas

Theses and Dissertations (Comprehensive)

Woodland caribou (Rangifer tarandus caribou) are a threatened species in Ontario's boreal forest. Caribou require habitat that supports appropriate forage, including large areas of lichen rich forests. This research examines two dynamics that influence woodland caribou habitat in northwestern Ontario. These dynamics are forest fires and land use policies. The effects of forest fires are assessed quantitatively at both the ecosite and landscape scales within Woodland Caribou Provincial Park. Land use policy and management activities are evaluated using a case study and a policy analysis of protected area and forest management approaches to woodland caribou conservation in this region. Forest …

Impacts At The Coast: Climate Change Influences On Lake Huron's Water Levels At Oliphant (Ontario), Kevin Tupman

Theses and Dissertations (Comprehensive)

Since 1998, climate change induced low water levels in the Great Lakes have caused environmental and socioeconomic impacts along most of the Great Lakes' shorelines. According to recent climate change research involving different water level scenarios, climate change over the next century may continue to cause water levels in the Great Lakes to decline. Such impacts may include wider shorelines, drying of coastal wetlands, and navigation hazards that may result in increased dredging activities. These impacts will have a strong influence on new shoreline management policies and planning. To better understand potential future impacts, a specific methodology was developed to …