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Confidence Interval Methods of Association Parameters for Correlated Bilateral Data
No full textPh.D.In many medical researches (e.g., ophthalmological and otolaryngology studies), clinical data often include bilateral measurements from paired organs (e.g., eyes and ears). Previous studies showed that ignoring the intraclass correlation for such bilateral data could lead to biased inference. Besides hypothesis testing, confidence interval (CI) method is also an active research field and provide more information thus it is our study focus. In this dissertation, we first propose CI methods for proportion ratio between two groups for correlated bilateral data. And then we extend the methods to multiple groups and propose simultaneous CI methods for odds ratio between one control group and multiple treatment groups. In addition, we also propose CI methods for odds ratio between two groups with consideration of stratification effect. The performance of the resulting CIs and SCIs are investigated in Monte Carlo simulation studies with respect to their empirical coverage probability and mean interval width. Real work examples are included to illustrate the application of the proposed methodologies
A Mathematical Framework for Power Management of a Microgrid Based on the Quality of Life in Rural Development
No full textM.Eng.Access to electricity can have beneficial impacts on the quality of life in developing communities. Advancements in health, safety, and education can be realized through powering lights, water pumps, fans, and other devices. However, 1.2 billion people lack access to electricity globally. Eighty four percent of those living without electricity are in rural areas. Electrification through a centralized grid may not be feasible due to location or cost. Therefore, rural electrification involves the use of islanded microgrids. Still, the implementation and sustainability of these systems is impeded in the rural setting due to a variety of challenges. Rural energy often relies on renewable resources that are intermittent in nature. Moreover, the size of the microgrid has a fixed capacity. Satisfying the demand can be difficult to sustain, especially as community development increases. In developing communities limited energy supply impacts basic needs. Therefore, power management is critical. The focus of this thesis is on a mathematical framework for integrating quality of life and power management. The approach must elucidate quantifiable relationships that exist between these domains in the context of sustainable rural electrification. A set of eleven parameters are used to define quality of life. These parameters capture the essence of sustainability. A quality of life model is proposed to assess and relate well-being to energy systems. This is achieved through three components. These components are the condition, community importance, and energy dependence of each quality of life parameter. The results of this model are utilized to identify requirements of the microgrid.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Versatile On-Chip Photonic Devices Inspired by Quantum Symmetry
No full textPh.D.Manipulation of light transport in the photonic devices serves as a basic demand for the fast operation of integrated photonics circuits. Optical signals in these devices are generally vulnerable to manufacturing imperfection and ambient randomness. The research on the robust light transport against such perturbations has become one focus in recent decades. Consequently, the conductive states at an interface of two media of topologically distinct symmetries are intensively investigated for their protected surface conduction and robustness against random perturbations. However, the unfortunate lack of tunability in topological photonic devices remains to be one of the major challenges for vast applications in the integrated photonics, because the propagation of light is only guided in a predesigned interface which cannot be modified after microelectronics fabrications. The aim of this dissertation is to tackle the obstacles on the more tunable photonic implementations of these symmetry-protected quantum states. We present a flexible topological photonic lattice that realizes multiple topologically nontrivial dispersion bands and multiple topological states with enriched topological features. Further, assisted by non-Hermitian engineering, we demonstrate a robust photonic zero mode sustained by a spatial quantum phase transition in a parity-time (PT) symmetric lattice, despite the same topological order across the entire system. These works equip topological photonics models with flexible creation and manipulation of protected topological states, enriched edge dynamics, and non-Hermitian-enhanced photonic zero modes. Our strategic manipulation of phase transition provides a novel route toward versatile functionalities and enriched physics in the field of nanophotonics and beyond.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Harmonic Syntax in Edvard Grieg's Lyric Pieces
No full textPh.D.Edvard Grieg's works are often cast as the work of a nationalist composer on the outskirts of Continental developments of musical importance. His harmonic innovations are largely unappreciated and unacknowledged. His musical works, often considered trite and folkish, have not garnered much attention from music theorists. This study finds that his Lyric Pieces, which span the majority of his creative life as a composer, offer fertile ground for exploring innovative harmonic syntactical construction within highly traditional confines. Some of these Lyric Pieces can challenge our sense of what constitutes normative functional harmonic analysis. Grieg's music can plausibly be analyzed as an adaptation of dualist Continental philosophical and music theoretical approaches, firmly placing him at the forefront of Western European musical development rather than at the outskirts. This study begins by observing how Grieg constructs cadences to establish the parameters of his harmonic syntax. Building off of that harmonic foundation, we then explore how Grieg constructs his harmonic syntax within his musical phrases, sections, and entire works. Of great advantage to this study is Grieg's regular adherence to traditional form, even when he articulates those forms in innovative ways. Grieg's adherence to standard musical forms allows for clear understanding of the alterations in harmonic syntax that he employs. The chapters move methodically through the construction of cadences, phrases, sections, and entire pieces to illustrate Grieg's harmonic syntax and wide range of musical variety within straight forward musical forms. This study serves, in some sense, as a dualist approach to the harmonic analysis of Grieg’s Lyric Pieces. Dualism was important in 19th Century German education, philosophy, and musical composition, as the result of two distinct kinds of musical thinking; (1) minor mode is the inverse of major and (2) Plagal harmony is complementary to functional harmony. Grieg's Lyric Pieces show the influence of the second of these dualistic approaches. Grieg's Lyric Pieces consistently explore the third, and least often emphasized, term in Western musical harmony, the Subdominant, and its relationship to Tonic rather than to Dominant. Certain of the Lyric Pieces articulate Tonic solely through opposition to Subdominant, falling into a two termed dualism comparable to the Dominant to Tonic relationship paradigmatic of most common-practice music. In other pieces, Grieg deploys both the Dominant and Subdominant with their own supporting phrases or formal sections to establish Tonic in complementary ways. Finally, in other works, a combination of both Subdominant and Dominant harmony appear in the articulation of Tonic.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Logarithmic Frequency Waveforms: A New Paradigm in Radar Signal Processing
No full textPh.D.This dissertation introduces a new class of Doppler estimation capable radar and communications waveforms called Logarithmic Frequency Waveforms (LFWs). These waveforms are created by mapping the magnitudes, phases, and spacing of good digital radar codes onto a set of carriers defined over a logarithmically warped frequency axis. This mapping preserves the digital code's autocorrelation when matched filtering is done over the warped frequency variable. The logarithm converts the multiplicative Doppler shift into a linear translation of the code's autocorrelation and thus is also used to estimate the waveform's Doppler shift. There are two main classes of Logarithmic Frequency Waveforms. The first class comprises the Logarithmic Frequency Codes (LFCs) and the second class encompasses the Logarithmic Frequency Rulers (LFRs). LFCs are created by mapping phased radar codes, such as Barker codes, Frank Codes, and Px codes, onto the magnitudes and phases of a set of carriers that are equally spaced after logarithmically warping the frequency axis. The main subtype of LFCs is made up of the Multicarrier Logarithmic Frequency Codes (MC-LFCs) which are waveforms created by transmitting all the carriers simultaneously. LFRs are created by spacing the carriers' logarithmic frequencies according to a Golomb Ruler. The first subtype constitutes the Multicarrier Logarithmic Frequency Rulers (MC-LFRs), created by transmitting all the carriers simultaneously. The next subtype is formed from Hopping Logarithmic Frequency Rulers (H-LFRs), which are transmitted by hopping the carriers sequentially in time. Extended Logarithmic Frequency Rules (E-LFRs) are created by using an Extended Golomb Ruler in the logarithmic frequency domain as the carrier frequency spacing mechanism. Finally, we introduce for the first time a hybrid type called Phased Logarithmic Frequency Rulers (P-LFRs), which are created by mapping phased radar codes onto the carriers of an LFR. Chapter 1 introduces the general model for an LFW, along with LFCs, LFRs, and their various subtypes. Examples of how these waveforms perform Doppler shift estimation are given along with plots of the waveforms, their frequency spectra, and their time and logarithmic frequency autocorrelations. Chapter 2 derives the logarithmic frequency domain Neyman-Pearson detectors for LFCs in Additive White Gaussian Noise (AWGN) and illustrates their performance numerically. The probability of a Doppler error is also derived and illustrated numerically. Chapter 3 follows the same blueprint for LFRs. Chapter 4 numerically illustrates the ambiguity functions for the various LFW subtypes along with their Doppler estimation performance in AWGN. The Doppler estimation performance is then compared with that of the Extended Matched Filter (EMF). Chapter 5 concludes the dissertation and discusses future work.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Heterogeneous Integration of Beta-Gallium Oxide and Diamond for High Power and Ultraviolet Electronic Applications
No full textPh.D.Diamond and beta-phase gallium oxide (β-Ga2O3) have been widely studied in recent years as emerging wide bandgap semiconductors. These materials are very promising in a variety of applications in power electronics and UV sensing due to their superior and unique material properties compared to conventional semiconductors. β-Ga2O3 can be easily processed into a free-standing single-crystal nanomembrane (NM) via mechanical exfoliation methods similar to those used for the synthesis of graphene from the bulk graphite. Once the sub-micron β-Ga2O3 NMs are obtained, they can be integrated via a transfer printing process with a wide range of substrates including flexible polymers. In this thesis, a high power flexible β-Ga2O3 NM Schottky barrier diode will be discussed, including the electrical and material characterization. In addition, the application of integrating the β-Ga2O3 NMs with other semiconductor substrates to form heterostructures is discussed, with the integration of free-standing β-Ga2O3 NMs with diamond. As is the case with other wide bandgap semiconductors, both β-Ga2O3 and diamond suffer from the lack of efficient dopants, rendering the fabrication of devices such as diodes and transistors from only one of these materials difficult. However, these materials complement the other to overcome the individual materials' deficiencies. The demonstration of a β-Ga2O3 NM-diamond heterojunction p-n diode by a novel integration method featuring the use of an ultrathin Al2O3 passivation layer at the interface is discussed, along with the electrical and material characterization. Furthermore, the ability of diamond to be assigned a negative electron affinity by the modification of the surface chemistry is presented, and the fabrication of heterostructures on diamond substrates for multiple electron affinities is addressed. The electrical and material characterization of the diamond/β-Ga2O3 heterostructure is presented and the application of this device towards high power and UV photodetection is demonstrated.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Body Image in High School Theatre Programs
No full textM.A.High school is a very vulnerable time for all students. It is when students begin to learn who they are, how they work, and what their future career paths may be. It is a time where social pressure is high and judgement is constantly passed through hallways and social media. In theatre, those onstage are regularly in the spotlight, being watched by their peers, teachers, and audience members. Those involved are judged on their abilities and physical attributes to put them into the best possible roles, making pressures high and self-worth low. When looking at the stress of high school and theatre combined, are these high school theatre programs contributing to students' negative body image and the early onset of eating disorders? First, I will survey two high school theatre programs: Maryvale High School and Academy of Theatre Art (ATA) as well as several students from varying programs around Western New York. The survey will include questions based on the National Eating Disorder Association Eating Disorder Screening Tool, their experience with body image in their specific programs, and how they feel their programs can improve. Next, based on the results, I will work with each director and try and establish how their programs can create a space for body acceptance and positivity. Do our local high school theatre programs make a difference in body image and how can we as theatre artists change the way bodies are viewed?**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Exercise in the Heat: Implications on Kidney Function and Acute Kidney Injury
No full textPh.D.The overall purpose of this dissertation project was to explore the mechanisms underlying the risk of acute kidney injury (AKI) following exercise in the heat. The first two experiments of this dissertation revealed that Doppler ultrasound measures of renal and segmental artery hemodynamics have excellent agreement using the standard approach (i.e., measurements of three cardiac cycles) and that increases in renal vascular resistance to non-exercise sympathetic activation were abolished with passive heating and restored following cooling recovery. After exploring the utility of using the Doppler ultrasound technique in this context, a series of studies were performed to investigate the AKI biomarker response to assess the risk of AKI in humans following exercise in the heat. The findings from the third experiment of this dissertation revealed that soft drink consumption exacerbated increases in AKI biomarkers which occurred with increases in serum copeptin and serum uric acid. Next, the fourth dissertation study demonstrated that the greatest magnitudes of hyperthermia and dehydration (i.e., during the nonintervention control trial) elicited the greatest increases in the AKI biomarkers and were interpreted as the risk of AKI being attenuated when attenuating hyperthermia, dehydration, and/or both during the exercise protocol. The final study revealed that high-fructose corn syrup-sweetened soft drink (HFCS) consumption increases vascular resistance in the kidney at rest and augments increases in segmental artery vascular resistance during the cold pressor test. Notably, these findings only occurred in the HFCS trial and were not observed when consuming an equal volume of a taste and caffeine-matched sucrose-sweetened and artificially-sweetened soft drink. Thus, these data provide evidence in humans that the fructose content of the beverage has direct physiological effects on the kidney. In summary, this dissertation produced many novel findings in human subjects that further our understanding of the risk of AKI following exercise in the heat.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
From Microbiota to Macroecology: Three Levels of Purple Martin Ecology
No full textPh.D.Purple martins (Progne subis) are migratory aerial insectivores in the swallow family. They have an unusually close relationship with humans in the breeding range and nest exclusively in man-made nest boxes in the eastern part of their range. This human association makes them an appealing 'model organism' for research due to the ease of locating colonies, the relative ease with which they can be handled, and the wealth of citizen science data and research which has been collated about them. Here, I use purple martins as a subject with which to address a series of broad ecological questions including 1) What are the fitness costs of parasitism? 2) What determines the level of parental care in an altricial species? 3) Is there a strong link between habitat suitability and fecundity or abundance? More specifically, I first address whether a conservation policy aimed at reducing ectoparasite abundance and associated fitness costs to nestling purple martins is effective. I found that the practice reduces the abundance of two of the three main ectoparasite species, but with equivocal fitness benefits to nestlings. Secondly, I use artificial intelligence to automate the classification of nest camera video footage to determine incubation attentiveness and provisioning rate in purple martins. I use the results of these analyses to study the main factors determining the level of parental care in this species, finding strong evidence for environmental limitation in both cases. Thirdly, I consider the role that nest ectoparasites may play as vectors, and find evidence for a novel transmission cycle of Bartonella. Finally, I create a species distribution model for the eastern breeding range of the purple martin and test the (often presumed) link between habitat suitability and species success. I find no link between habitat suitability and fecundity or local abundance, but a threshold-type relationship between habitat suitability and regional abundance. This suggests that local success is driven largely by biotic and stochastic factors, and raises the possibility that purple martins are experiencing a time lag in their distribution.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Technology-Enhanced Assessment Item Types and Their Relations to Student Mathematics Performance, Teacher Perceptions, and Concerns
No full textPh.D.Computer-based testing has been attractive to educators for multiple decades. Although there is a growing trend of implementing computer-based tests in standardized state testing, little is known about whether and how technology-enhanced items influence student performance and engagement in standardized tests. We also rarely know about teachers’ use and concerns on technology-enhanced assessment items. Technology-enhanced assessment items have the potential to provide improved measures of student knowledge over traditional item types because they require students to produce rather than select a response. The purpose of this dissertation study is to investigate how technology-enhanced items (i.e., drag and drop, keyboard entry, and multiple enhancements) impact performance and engagement of middle school students when taking standardized tests. This study also investigates how teachers view technology-enhanced items. In this study 338 middle school students took an online test that included both multiple-choice and technology-enhanced items to measure middle school Common Core Mathematics standards. 40 teachers completed a survey that asks about their concerns and perceptions of the impact of use of technology-enhanced items. In order to analyze student performance and engagement, a paired T-test and ANOVA were used. In order to evaluate teacher perceptions and concerns on technology-enhanced assessment items, a survey and follow-up interviews with a small number of teachers were conducted. The results of the study revealed that students perform better and spend less time with multiple-choice items but engage better with technology-enhanced items. There was no variation between subgroups identified for the performance difference between multiple-choice items and technology-enhanced items. Student surveys revealed that, students mostly show a positive attitude towards technology-enhanced item types. A similar result revealed by teacher surveys, teacher self-reported survey results suggested that most teachers also show a positive attitude towards technology-enhanced items but lack knowledge and experience with them. The findings of this study contribute to existing literature on the topic by explaining the performance and engagement variation between technology-enhanced items and multiple-choice item types. This study also provides suggestions to school administrators, providers of professional development, and teachers regarding what supports teachers need in order to facilitate their efforts when using technology-enhanced items. The findings of the study lay down a foundation for future studies in this field.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*