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Ultraluminous X-Ray Sources In Andromeda Galaxy: Two Recent Discoveries And Their Implications, Amanpreet Kaur

All Theses

Ultraluminous X-ray sources are believed to be associated with X-ray binaries, in which an accreting black hole generates X-ray luminosities in excess of 10 39 erg/s. The nature of the companion star and the underlying physics of the accretion process is not yet established with certainty. In particular, whether or not the accretion is super/sub Eddington is an open question, as is the mass of the companion star. We discuss the first two ULXs recently discovered in M31 and investigate the nature of their underlying sources. We present the X-ray observations for ULX-1 in detail and discuss its implications for …

Bioswellable Amphiphilic Copolymers, David Ingram

All Theses

The suture is one of the most commonly used medical devices, consisting of a fiber, a surgical needle and the packaging in which it is stored. The fiber itself remains after implantation for a defined time and is responsible for the approximation of the wound during the healing process. The needle merely serves to aid in insertion, and preferably has a diameter larger than the diameter of the fiber .
The 1970's marked the birth of a new family of fibrous materials for the approximation of wounds: synthetic absorbable sutures. This family has the ability to provide wound support during …

Investigation Of Auxiliary Winding Harmonic Resonance Phenomena In Single Phase Induction Motors, Gaurav Singh

All Theses

In recent years, the proliferation of single phase power electronics based loads has given rise to a number of power quality issues in the power grid. Harmonics in voltage and current waveforms are one of the biggest problems in this family of power quality issues. Until some years back, power system utilities did not consider harmonics due to small single phase loads to be a big problem. In fact, only large loads were considered as potential hotspots for power quality problems. However, the advent of compact fluorescent lamps (CFLs), personal computers and consumer electronic devices, which utilize rectifier front ends, …

Can The Application Of A Landscape Designed Learning Environment Enhance Education?, Virginia Bailey

All Theses

There is a need for a restructuring the way that a child's learning environment is designed. Currently, the mainstream educational design process ignores the notion that children have different ways of learning. Furthermore, when there are so many distractions, how we successfully reach a child's mind has become a challenge. The current school system is structured in a manner that does not address the presence of these distractions, often causing overstimulation and inattentiveness. Designing for children should be approached in a way that all senses are engaged. Having opportunities for hands-on learning inside and outside of the classroom is important …

Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan

All Theses

Growing fresh water needs have led to an interest in water desalination using reverse osmosis (RO) membranes. Energy consumption has a large share in the expenses incurred to drive a reverse osmosis desalination system. With depleting fossil fuel reserves, tapping renewable sources of energy is a promising alternative to meet the energy requirements. Wind power coupled to an RO desalination system is a potential means of delivering clean water using sustainable energy. This work investigates modeling of a conceptual wind-energy-driven RO desalination system that is made possible because of an air-pressure energy storage mechanism. Bench-scale experiments were performed on an …

Measuring Learning Through Cross Sectional Testing, Steve Lovett, Jennie Johnson

Management Faculty Publications

The measurement of student learning is becoming increasingly important in U.S. higher education. One way to measure learning is through longitudinal testing, but this becomes especially difficult when applied to cumulative learning within programs in situations of low persistence. In particular, many Hispanic Serving Institutions (HSIs) find themselves in such situations. Cross sectional testing is a pragmatic alternative, so long as maturity and selection effects can be estimated. The purpose of this paper is to demonstrate the utility and mechanics of measuring learning through cross sectional testing.

Characteristics Of Public Alternative High Schools Specifically For Students Placed At-Risk: A National Study Using The 2003-04 And 2007-08 Schools And Staffing Survey, Masashi Izumi

Dissertations

In this study I investigated determinants of the average daily attendance (ADA) and graduation rate of public alternative high schools specifically for students placed at-risk by analyzing the nationally representative data from Schools and Staffing Surveys of 2003-04 and 2007-08. I built three models via successive block entry, predicting the ADA and graduation rate by (a) student demographics, (b) staffing characteristics, and (c) school processes. Through multiple regression analyses on ADA, I found (a) a positive relationship between career technical education and ADA; and (b) a negative relationship between teacher-student ratio and ADA. Through the set of multiple regression analyses …

An Inquiry Approach To Reading Instruction: A Case Study Of The Relationship Between Instruction And Motivation, Tammy Turri-Scodeller

Dissertations

This research is a qualitative case study analysis of the experiences of five fifth grade students who were involved in a classroom, action research project. The purpose of this action research was to measure the impact of this method of instruction on reading motivation of the fifth grade class as a whole. From the action research project, five, individual, student cases were purposefully sampled for further in-depth analysis. The objective of the individual student case study analysis was to explain how the behaviors of five students with a low level of reading achievement, activity, and motivation changed, or did not …

From Crisis To Stability: A Case Study Of Presidential Leadership At A Christian College, Jeffrey Gill

Dissertations

Despite healthy growth in past decades, in a time of national and global economic instability small, private Christian colleges now find themselves in a precarious position. Leading effectively in such colleges and universities in a time of external and/or internal crisis is a great challenge.

This research is about a small, Christian college with documented evidence of having survived two significant enrollment and financial crises (early 1990s and 2008-09), and is now stable, all under the leadership of a president who served during the 19 year time period of crisis and stability. The purpose of this study is to investigate …

Ammonia Measurements And Emissions From A California Dairy Using Point And Remote Sensors, Kori D. Moore, E. Young, C. Gurell, Michael D. Wojcik, Randy S. Martin, G. E. Bingham, R. L. Pfeiffer, J. H. Prueger, J. L. Hatfield

Civil and Environmental Engineering Faculty Publications

Ammonia (NH3) is an important trace gas species in the atmosphere that can have negative impacts on human, animal, and ecosystem health. Agriculture has been identified as the largest source of NH3, specifically livestock operations. NH3 emissions from a commercial dairy in California were investigated during June 2008. Cattle were held in open-lot pens, except for young calves in hutches with shelters. Solid manure was stored in the open-lot pens. Liquid manure from feed lanes was passed through a solids settling basin and stored in a holding pond. Passive sensors and open-path Fourier transform infrared spectrometers (OP-FTIR) were deployed around …

Flow Measurement Accuracies Of In-Service Residential Water Meters, Devin M. Stoker, Steven L. Barfuss, Michael C. Johnson

Civil and Environmental Engineering Faculty Publications

Water utility managers generally agree that water meters, especially mechanical water meters, experience a degradation of accuracy over time. This degradation is a function of several factors, such as wear, water quality, water velocities, throughput volumes, and installation and handling. Both a thorough understanding of the factors that affect meter accuracy and the ability to pinpoint, if possible, the optimal lifespan of any particular type of water meter in a residential distribution system are desirable for improved system management. The purpose of this article was to investigate the relationship between meter accuracy degradation and factors such as age, wear, and …

Impact Of Sampling Frequency On Annual Load Estimation Of Total Phosphorus And Total Suspended Solids, Amber Spackman Jones, Jeffery S. Horsburgh, David King Stevens, Nancy O. Mesner, Ronald J. Ryel

Civil and Environmental Engineering Faculty Publications

The determination of sediment and nutrient loads is typically based on the collection and analysis of grab samples. The frequency and regularity of traditional sampling may not provide representation of constituent loading, particularly in systems with flashy hydrology. At two sites in the Little Bear River, Utah, continuous, high-frequency turbidity was used with surrogate relationships to generate estimates of total phosphorus and total suspended solids concentrations, which were paired with discharge to estimate annual loads. The high frequency records were randomly subsampled to represent hourly, daily, weekly, and monthly sampling frequencies and to examine the effects of timing, and resulting …

Analysis Of Genotype, Phenotype, And Age Progression In Phelan-Mcdermid Syndrome, Sara Sarasua

All Dissertations

Phelan-McDermid syndrome is a developmental disability syndrome associated with deletions of the terminal end of one copy of chromosome 22q13. The observed chromosomal aberrations include simple terminal deletions, interstitial deletions, deletions and duplications, and duplications without deletions. All patients have some degree of developmental disability and many also have hypotonia, autism, minor dysmorphic features, and seizures. I performed an epidemiological and cytogenetic investigation to better understand the etiology of Phelan-McDermid syndrome and to provide information to patients and their families, clinicians, and researchers investigating developmental disabilities. Deletions vary widely in size, from 60 kb to more than 9 Mb, but …

A Dynamic Network Analysis Of Innovation And Leadership In Two-Year Colleges, Melissa Mcfarland

All Dissertations

The purpose of this study was to investigate the role of leadership and its influence on innovation at a two-year college, paying particular attention to the network structure, the influence of leadership (formal and informal), and environmental influence. The goal was to learn about the nature of innovation at two-year colleges by studying the environment and leadership at these institutions, relative to theory, specifically complexity theory and dynamic network analysis, to gain an understanding of the complex dynamics that makes up the two-year college. The study looked at these influences and innovation as dynamic, changing processes between interconnected agents within …

The Effects Of 0.2 Hz Varying Latency With 20-100 Ms Varying Amplitude On Simulator Sickness In A Helmet Mounted Display, Matthew St. Pierre

All Dissertations

The relationship between the occurrence of simulator sickness (SS) and the several characteristics of latency (i.e., added latency, amplitude of latency, and frequency of latency) in a helmet-mounted display (HMD) were explored in this study. The experience of SS while using an HMD has often been attributed to system latency. These findings are typical in research where HMDs with head trackers are used. The current study explored the effects of 200 ms added constant latency, latency varying at 0.2 Hz with a constant 100 ms amplitude, and latency varying at 0.2 Hz with a 20-100 ms varying amplitude on the …

Assessing The National Innovation System In A Developing Country Context: A Framework And Evidence From Thailand, Maleena Parkey

All Dissertations

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Asymptotics For The Arc Length Of A Multivariate Time Series And Its Applications As A Measure Of Risk, Tharanga Wickramarachchi

All Dissertations

The necessity of more trustworthy methods for measuring the risk (volatility) of financial assets has come to the surface with the global market downturn This dissertation aims to propose sample arc length of a time series, which provides a measure of the overall magnitude of the one-step-ahead changes over the observation time period, as a new approach for quantifying the risk. The Gaussian functional central limit theorem is proven under finite second moment conditions. Without loss of generality we consider equally spaced time series when first differences of the series follow a variety of popular stationary models including autoregressive moving …

Molecular Genetics Of Nodule Number Regulation: Cloning, Characterization And Functional Studies Of The Root Determined Nodulator1 (Rdn1) Gene In Medicago Truncatula, Tessema Kassaw

All Dissertations

Nitrogen is critical to life. However, the majority of nitrogen on earth (in the atmosphere) is inert and unavailable to nearly all organisms. Metabolically diverse prokaryotes are the only organisms capable of fixing atmospheric nitrogen; rhizobia set up a symbiosis with legume plants allowing the plants to benefit from this ability. Since nodulation and the subsequent nitrogen fixation processes are energy intensive, the host plant must balance hosting of the rhizobia by limiting the number of nodules it forms through a mechanism called Autoregulation of Nodulation (AON). My study of mutants in the model legume Medicago truncatula defective in AON …

Updated Force Model For Milling Nickel-Based Superalloys, Andrew Henderson

All Dissertations

Nickel-based superalloys are commonly used in applications which require high strength and resistance to creep and oxidation in extreme conditions. All nickel-based superalloys are considered difficult to machine; however, cast gamma-prime-strengthened nickel-based superalloys are more difficult to machine than common nickel-based superalloys. Machining comprises a significant portion of manufacturing processes and with advancements in technology and material properties, the methods and models used must be adapted in order to keep pace.
In this research, correlations are made, using fundamental principles, between measurements made with on-machine touch probes and the cutting tool's wear state, those correlations are used in an adaptive …

Assessment Of Fidelity To Data And Robustness To Uncertainty To Assure Credible Predictions In The Modeling Of Wind Turbine Blades, Kendra Van Buren

All Dissertations

In the field of wind energy, modeling and simulation techniques provide an efficient and economical alternative to experimentation for studying the behavior of wind turbines. Numerical models however are approximations of reality, thusly making it crucial to evaluate various sources of uncertainties that influence the model predictions. Credibility of a numerical model rests on the model's ability to replicate existing experimental data, widely known as fidelity-to-data. This dissertation advocates that fidelity-to-data, while necessary, is insufficient to claim credibility of a numerical model. Herein, the objective is to develop numerical models that not only provide agreement to experimental data, but also …

Supply Chain Network Design: Risk-Averse Vs. Risk-Neutral Decision Making, Alireza Madadi

All Dissertations

Recent events, such as the Heparin tragedy, highlight the necessity for designers and planners of supply chain networks to consider the risk of disruptions in spite of their low probability of occurrence. One effective way to hedge against supply chain network disruptions is to have a robustly designed supply chain network. This involves strategic decisions, such as choosing which markets to serve, which suppliers to source from, the location of plants, the types of facilities to use, and tactical decisions, such as production and capacity allocation. In this dissertation, we focus on models for designing supply chain networks that are …

Phase Transformation In Ti-Mo-O, Herbert Boeckels

All Dissertations

The present dissertation has investigated the effect of oxygen on the ù and á phase stability in metastable Ti-Mo â titanium alloys using thermal analysis, hardness measurements, electron microscopy, and x-ray diffraction.
Single crystal x-ray diffraction has shown that oxygen atoms are located in the tetrahedral interstitial lattice sites in the rapidly cooled bcc Ti crystal structure, interfering directly with the reversible displacive formation of ù, with this transformation involving collapse of the bcc lattice along â. Subsequent thermal exposure of reversible ù, as occurring during slower cooling, heating, and aging, prompts short range diffusion and the formation of chemical …

Analyses Of Consumer Perceptions, Farmer Challenges, Polyamine, And Amino Acid Content Of Organic And Conventional Fresh Produce Grown In South Carolina, Emily Steinberg

All Dissertations

Execution of the USDA organic standards led to more support for local food as distinct from organic food. The current study was conducted to examine fresh produce perceptions and purchasing decisions of S.C. consumers. Four-hundred and eight S.C. consumers were surveyed at S.C. grocery stores. More than one-third of the S.C. consumers not knowing about the 'certified S.C. grown' program suggest that the S.C. Department of Agriculture (SCDA) may want to improve the promotion of their program. Eighty-five percent of consumers indicated that they would choose local over organic. This information would be useful to local S.C. produce farmers who …

Network Traffic Analysis Using Stochastic Grammars, Chen Lu

All Dissertations

Network traffic analysis is widely used to infer information from Internet
traffic. This is possible even if the traffic is encrypted. Previous work uses
traffic characteristics, such as port numbers, packet sizes, and frequency,
without looking for more subtle patterns in the network traffic. In this work,
we use stochastic grammars, hidden Markov models (HMMs) and probabilistic
context-free grammars (PCFGs), as pattern recognition tools for traffic
analysis.
HMMs are widely used for pattern recognition and detection. We use a HMM
inference approach. With inferred HMMs, we use confidence intervals (CI) to
detect if a data sequence matches the HMM. To …

Policy Evaluation Using Cost-Benefit Analysis: Empirical Ramifications For Two Policy Issues, Elizabeth Crouch

All Dissertations

Using two distinct health policy issues my research examines the relevance and ramifications of using cost-benefit analysis (CBA) to demonstrate real-world impacts of the policies. My dissertation discusses how these two situations represent particular challenges to cost-benefit analysis. The challenges have specific implications for how scholars, agencies, and government entities should use CBA to evaluate policies. Specifically, my research finds that by separating CBA into four different approaches, a much more complete, and less assumption-laden, CBA can be accomplished.

Principals' Experiences Regarding Culturally Responsive Leadership Preparation And Practices That Promote Academic Achievement Of African American Students, Monica Brown

All Dissertations

Culturally responsive education improves the educational success of ethnically diverse students (Gay, 2002). The research presented states the case of the need of culturally responsive leadership preparation programs that influence the practice of culturally responsive principals. Emerging evidence has found that preparation programs impact the efficacy of future school leaders (Darling-Hammond, LaPointe, Meyerson, Orr, & Cohen, 2007; Jackson & Kelly, 2002). A large body of literature points to persistent achievement gaps for children of color and especially for African American males and demands that school leadership preparation attend to issues of cultural competence (Dantley, 2005; Evans, 2007; Lopez, Magdeleno, & …

Coaching Equestrian Vaulting: The Motivation Behind Volunteer Coaching, Amy Mccune

All Dissertations

The purpose of this research was to identify the primary motivations for people to become and continue as equestrian vaulting coaches. Using a nomothetic context for research, this study focused on gaining a better understanding of equestrian vaulting coaches by identifying factors that generally motivate their participation in the sport. The first research question related to what motivates someone to become a vaulting coach while the second question related to what motivates these coaches to continue in the coaching role.
Fifteen female coaches were selected for interviews from the American Vaulting Association membership. Interview questions were based on a preliminary …

The Relationship Between Turning Points And Travel Styles: A Study Of First Generation Older Korean Americans, Young-Joo Ahn

All Dissertations

People experience various significant events across their life course. The purpose of this study was to explore what turning point events occur and how these events influence travel style among first generation older Korean immigrants. To accomplish this, 33 interviewees were recruited by using theoretical sampling and a semi-structured interview with the retrospective interview technique.
Following the grounded theory approach (Strauss & Corbin, 1990, 1998; Corbin 2008), several themes emerged that created turning point events and travel styles among first generation older Korean immigrants. Turning point events divided into eleven categories. In the findings, however, the participants seemed to experience …

Understanding The Relative Attentional Demands Of The Dimensions Of Interface Consistency, Jeremy Mendel

All Dissertations

A consistent interface is thought to be beneficial because it allows users to draw on previous training and experience when operating a new interface. Design guidelines like the eight golden rules of interface design argue that a highly consistent interface improves system usability (Shneiderman, 1987). However, interface consistency is not monolithic; instead it is a complex, multidimensional construct. I refer to the two dimensions of interface consistency as perceptual consistency (the appearance) and conceptual consistency (the functionality) of an interface. Perceptual consistency considers aspects like interface layout and orientation; conceptual consistency considers how the system operates or responds. I sought …

Key Strategies Of Sustainable Real Estate Decision-Making In The United States: A Delphi Study Of The Stakeholders, Pernille Christensen

All Dissertations

Sustainable real estate is a growing sector within the commercial real estate industry, yet there is still a lack of consistency among the multitude of sustainability performance measurements and reporting requirements around the world. As a result of this confusion, stakeholders have developed different strategies and requirements for sustainability, which in turn makes it difficult to communicate with other stakeholders about sustainability in real estate. Without the ability to communicate with other stakeholders about sustainability efforts, comparison of sustainable real estate becomes a challenge, thus impeding progress towards a competitive sustainable real estate market.
This study presents the results of …