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Theses and Dissertations

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Love and Hip Hop
Love and Hip Hop
This study seeks to make meaning of Black college women's interpretations of Black womanhood through the lens of urban reality television. This study highlights the consumption of urban reality television in higher education and works to determine how the confluence of identity development and media influences inform understandings of Black womanhood among Black undergraduate women. I examined their interpretations of (1) urban reality television, (2) Black womanhood, (3) campus life, (4) their interactions with family and friends, (5) role models, and (6) romantic relationships. My preliminary findings indicate that while the students frequently consumed these shows for entertainment purposes, their understandings of Black womanhood were largely shaped by family and role models. Still, parallels existed between the women's lived experiences and the portrayals of reality on television. Specifically, the participants determined the attitudes surrounding committed relationships among urban reality cast members reflect hook-up culture on-campus. Additionally, both the women cast in the shows and the respondents used predominantly White systems (educational system, the media) to acquire social mobility and improve their socioeconomic status., Submitted Note: A Dissertation submitted to the Department of Educational Leadership and Policy Studies in partial fulfillment of the Doctor of Philosophy., Degree Awarded: Fall Semester 2015., Date of Defense: November 2, 2015., Keywords: Black, Reality Television, Women, Bibliography Note: Includes bibliographical references., Advisory Committee: Tamara Bertrand Jones, Professor Directing Dissertation; Felicia Jordan Jackson, University Representative; Kathy Guthrie, Committee Member; Ayesha Khurshid, Committee Member.
Love in Retrodiction
Love in Retrodiction
Love in Retrodiction is a novel., A Dissertation submitted to the Department of English in partial fulfillment of the requirements for the degree of Doctor of Philosophy., March 31, 2023., Apocalyptic literature, Fiction, Novel, Includes bibliographical references., Skip Horack, Professor Directing Dissertation; Jeff Broome, University Representative; Bob Shacochis, Committee Member; Diane Roberts, Committee Member; Elizabeth Stuckey-French, Committee Member.
Love of My Life
Love of My Life
A memoir excerpt about growing up in a home with an abusive mother, marrying a controlling Army infantryman, and falling in love with an emotionally distant Marine., A Thesis submitted to the Department of English in partial fulfillment of the requirements for the degree of Master of Fine Arts., June 9, 2022., adultery, bildugsroman, creative nonfiction, memoir, military, oregon, Includes bibliographical references., Diane K. Roberts, Professor Directing Thesis; Rhea Estelle Lathan, Committee Member; Robert G. Shacochis, Committee Member.
Love's Working Arm
Love's Working Arm
This dissertation traces the process by which American Lutherans used charity work, particularly the provision of social services to refugees, to enter mainstream American society in the middle of the twentieth century. In the years following World War I, after Americanization campaigners branded them a suspicious and foreign element, American Lutherans began a significant reappraisal of their position in American society. Illustrating the increasing secularization of American society during this period, Lutheran leaders downplayed their ethnic and theological differences to seek a closer relationship with the American government and participation in cooperative charity projects as a way to enhance their image with the American public. By the end of World War II, millions of Lutheran laypeople set aside their differences to support their church's role in the government's refugee resettlement program. Church leaders encouraged their members to donate money, food, or clothing, sponsor refugees, and welcome them into American churches. They also lobbied for the inclusion of refugees in government programs that typically had citizenship and residency requirements, such as county poor relief. In the process, they helped to create the parameters of the public-private partnership between government bodies and religious voluntary agencies that still exists today to assist refugees entering the United States., Submitted Note: A Dissertation submitted to the Department of History in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Summer Semester, 2014., Date of Defense: April 18, 2014., Keywords: Displaced Persons, Immigration, Lutheran, Refugees, World War I, World War II, Bibliography Note: Includes bibliographical references., Advisory Committee: Suzanne Sinke, Professor Directing Dissertation; Amanda Porterfield, University Representative; Jennifer Koslow, Committee Member; Will Hanley, Committee Member; Edward Gray, Committee Member.
Low Cost Carrier Entry, Incumbent Responses and Spatial Competition in the U.S. Airline          Industry
Low Cost Carrier Entry, Incumbent Responses and Spatial Competition in the U.S. Airline Industry
The successful emergence of the Low Cost Carriers (LCCs) represents one of the most important structural developments in the U.S. airline industry after it was deregulated in 1978. With a more efficient cost structure and a different business strategy, in 2006 the LCCs served 32.9% of all domestic origin and destination passengers and about 75% of all domestic passengers had access to LCC service. Moreover, Southwest Airlines, the pioneer of the Low Cost business model is currently the largest U.S. carrier in terms of passengers. It should be of no surprise then that the impact of LCCs on airfares and airline markets in general has attracted a lot of attention from economists, policy makers and the general public. In this dissertation I will address several limitations of the previous literature on the topic of the impact of LCCs on airfares. Previous analyses do not fully capture the spatial nature of competition in airline markets. The arbitrage actions of travelers selecting among alternative airports is likely to create co-movements of prices across routes with common or nearby destinations. Therefore airfares in adjacent routes are likely to be correlated and the competitive effects of the LCCs are not limited to the routes they enter but also extend to adjacent routes. In the first chapter of the dissertation I examine alternative empirical approaches to assessing the cost savings travelers have enjoyed from low cost carriers, when the impact extends across adjacent routes. I demonstrate the advantages of spatial econometric approaches in capturing indirect effects that are missed in standard regression models. An empirical analysis of Southwest Airlines and other low cost carriers for 1998 and 2004 in top U.S. routes is provided to illustrate how estimates of cost savings may be substantially altered when attention is paid to spatial modeling considerations. In addition to controlling for time-invariant route characteristics, the availability of route level panel data also makes it possible to examine the dynamic nature of competition in airline markets. In chapter 3, I extend the route level analysis by estimating a spatial panel model with time and route specific fixed effects and investigate the dynamic responses of the incumbent carriers faced with entry from LCCs. The empirical analysis revealed that the incumbent legacy carriers reduce airfares pre-emptively before LCCs enter the route, most likely in an attempt to gain market share and induce loyalty among travelers. Also the results from the empirical analysis suggest that most of the pro-competitive effects manifest themselves after the LCC entry and they accumulate beyond the initial entry period. While the evolution of the post-entry fares charged by the incumbents follows the same pattern irrespective of the identity of the carriers, the Southwest effect is twice as large compared to the effect of the other LCCs. When LCCs exit a route, the incumbents raise airfares to the point where most of the pro-competitive entry effects are being offset. This chapter fills the gap in the literature on the dynamic responses of the incumbents to LCC entry by making use of spatial econometric panel data models that allow for explicitly modeling time and space fixed effects as well as the spatial dependence among route level airfares. Moreover, I show how spatial econometrics methods can be used to fully assess both the direct and indirect effects of the LCCs. The savings to travelers that can be attributed to competition from LCCs are calculated for each quarter from the fourth quarter of 1994 to the fourth quarter of 2004. In contrast to the impact on route level airfares, the impact of LCCs on airport level airfares is less well studied in the literature. In Chapter 4, I estimate the effect of LCC entry on an airport level fare index as well as on the fare differential between alternative airports. The results indicate that the entry of Southwest Airlines at an airport induces fare effects with a dynamic pattern similar to that observed in the route level analysis. Both pre-entry and post entry effects were identified for Southwest, but the estimated effect of the other LCCs was close to insignificant indicating their inability to exert more generalized competitive pressures at airport level, beyond their actual service offerings. Moreover, the presence of spatial correlation among airport level airfares suggests that the competitive conditions at one airport either through entry from LCCs or other factors, will be reflected in the prevailing airfares at nearby airports. Overall, the results of the dissertation improve the understanding of the role of the LCCs in the US airline industry by making use of the best available data and the proper estimation techniques, in particular spatial econometrics methods that are amenable to the spatial nature of data from the airline industry., Submitted Note: A Dissertation submitted to the Department of Economics in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Degree Awarded: Summer Semester, 2007., Date of Defense: Date of Defense: June 26, 2007., Keywords: Low Cost Carriers, Spatial Econometrics, Airlines, Bibliography Note: Includes bibliographical references., Advisory committee: Gary M. Fournier, Professor Directing Dissertation; Mark W. Horner, Outside Committee Member; David A. Macpherson, Committee Member; Thomas W. Zuehlke, Committee Member.
Low Dimensional Electron Correlated Materials
Low Dimensional Electron Correlated Materials
This PhD thesis is devoted to investigation of inorganic materials with low-dimensional structures. Such materials attract significant fundamental and applied interest due to the potential to achieve highly anisotropic properties, which can be controlled by various external stimuli. After brief introduction to this research area in Chapter 1 and description of experimental and theoretical methods in Chapter 2, we describe the study of ternary manganese selenides, Na2Mn2Se3 and Na2Mn3Se4, in Chapter 3. The relationship between the layered crystal structure of these materials and their magnetic behavior is discussed based on the arrangement of magnetic sites in each layer, and results of quantum chemical calculation on Na2Mn2Se3 and Na2Mn3Se4 indicate both compounds are semiconductors. Na2Mn2Se3 does not exhibit magnetic ordering down to 1.8 K, but strong antiferromagnetic correlations were confirmed by field-dependent magnetization measurements. Neutron diffraction study on powder and single crystal samples also did not reveal clear signatures of magnetic ordering. The strong magnetic frustration was confirmed by calculating the frustration factor. A new antiferromagnetic compound, Na2Mn3Se4, was also discovered. It exhibits antiferromagnetic transition at 27 K. Additional magnetic transition is observed at 50 K in single crystal and powder neutron diffraction studies. The magnetic structure of this material shows a complex combination of ferromagnetic and antiferromagnetic interactions that alternate along the crystallographic a-axis. Strong magnetic frustration due to triangulated spin arrangement is confirmed. Synthesis, crystal structure, and magnetic properties of layered materials ACeSe2 (A = Li, Na) are described in Chapter 4. The unconventional magnetism of these compounds is due to the arrangement of magnetic sites on the regular triangular lattice, which causes strong magnetic frustration. A detailed investigation of magnetic properties reveals no magnetic ordering down to 1.8 K. The Weiss constant, determined from fitting experimental data to the Curie-Weiss law, is –71 K, suggesting a very large magnetic frustration factor for this system. The relationship between the structural and magnetic properties of the geometrically frustrated magnetic system is discussed. The extension of studies of layered structures to potentially two-dimensional magnetic materials, Fe3GeTe2 and Bi2MnSe4, is described in Chapter 5. These crystal structures contain stacks of 2D magnetic sheets interacting through weak interlayer van der Waals forces. Chemical vapor transport method is employed to grow high-quality single crystals. The structural and magnetic properties of these materials, including magnetocrystalline anisotropy of bulk samples, were confirmed by temperature dependent magnetic susceptibility measurement. The potential to modify magnetic behavior for few-layer materials, down to the monolayer limit obtained by mechanical or liquid phase exfoliation methods, is yet to be investigated. Chapter 6 describes the study of one-dimensional structures that contain tubular or ribbon-shaped polyphosphide fragments. Thin nano-ribbons were obtained by mechanical and liquid-phase exfoliation of bulk KP15, due to the weak van der Waals interactions between the polyphosphide tubes. Optical bandgap slightly increases as the thickness of nano-ribbons decreases which is an indication of bandgap tunability in the material. Nevertheless, the results of Raman spectroscopy, high resolution transmission electron microscopy, and selected area electron diffraction studies suggest the decreased stability of the samples that contain thinner nanoribbons (<20 nm)., Submitted Note: A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Summer Semester 2018., Date of Defense: July 6, 2018., Keywords: Crystal structure, Geometrically frustrated, Low dimensional material, Magnetic structure, Magnetism, Strong electron correlation, Bibliography Note: Includes bibliographical references., Advisory Committee: Michael Shatruk, Professor Directing Dissertation; Eric Hellstrom, University Representative; Thomas E. Albrecht-Schmitt, Committee Member; Albert E. Stiegman, Committee Member.
Low Energy Manufacturing and Optimization of Perovskite Film Growth for Application in          Wire-Shaped Photodetection
Low Energy Manufacturing and Optimization of Perovskite Film Growth for Application in Wire-Shaped Photodetection
This thesis aims to develop a deeper understanding of perovskite thin film growth and stability for integration into photodetectors for mechanoluminescent sensing applications. Photodetectors play an important role in our society, acting as the sensing mechanism for most remotes, switches, triggers, and indicators. As new thin-film semiconducting materials are synthesized, the volumetric footprint of photodetectors decreases to opens doors for multi-functional materials such as wearable electronics and sensor integrated composites. The recent synthesis of methylammonium lead halide perovskite has triggered a renaissance due to being solution processable and high performing at relatively low fabrication cost. The optoelectronic properties of perovskite are strongly dependent on the crystalline quality and morphology of the film. Uniform temperature strongly affects nucleation and grain growth rate, which dictate the morphology, uniformity, coverage, and quality of the perovskite layer. A novel heating method was developed in an effort to gain uniform temperature control during the perovskite annealing and deposition process. This novel method was applied to carbon nanotube yarns (CNYs), which resulted in the successful fabrication of flexible wire-shaped photodetectors. The CNY perovskite photodetectors produced a competitive detectivity (1.76 x 1011 Jones), on/off ratio (45), and response time (0.132 s), but suffered instability due to the perovskite’s reaction to high temperatures and moisture. Thin-film growth dynamics of the more stable ‘triple cation’ perovskite (TCP) (Cs0.05(FA100-xMAx)0.95Pb(I1-xBrx)3) were studied which revealed crystallinity could be improved through the tuning of both the organic cation and halide sites. The transition toward scalable fabrication methods was made by studying the material’s behavior towards anti-solvent bath crystallization. It was revealed that the use of diethyl ether would lower the annealing temperature, which resulted in thermally stable, phase pure, high quality, large grain thin films. Photodetectors were fabricated using the optimized TCP, which showed stability towards temperatures of 85° C for up to 10 hours with an extremely rapid response time of 12.4 μs. Finally, a model predicting TCP film quality as a function of annealing time and temperature was developed to calculate ideal annealing conditions for future commercial and scientific applications., A Dissertation submitted to the Department of Industrial and Manufacturing Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy., June 22, 2020., Crystal Growth, Perovskite, Photodetectors, Scalable Annealing, Structural Health Monitoring, Thermal Stability, Includes bibliographical references., Okenwa Okoli, Professor Directing Dissertation; Kenneth Hanson, University Representative; Tarik Dickens, Committee Member; Zhibin Yu, Committee Member.
Low Temperature Microwave Driven C1 Reactions
Low Temperature Microwave Driven C1 Reactions
The selective heating observed by Spencer et al. in 1946 by microwave irradiation is the same observation that is showing up in recent articles published on microwave driven reactions. The unique way in which microwaves heat some materials selectively (reagents and catalysts) depending on their physical properties facilitates lower observed reaction temperatures, lower energy consumption, and higher reaction rates when compared to traditional thermal heating. Because of these advantages of microwave heating there has been an increase in publications on the topic over the last 25 years, from 3 publications in 1986 to 4000 in 2011. In early literature the observed microwave efficiencies were explained by the reality that microwaves instantaneously heat systems whereas convective heating requires time to reach the desired temperature. The literature debate now hinges around if there is a "special microwave" (non thermal) effect. In the studies presented here, two microwave driven chemical reaction systems are investigated. A heterogeneously catalyzed one in which methanol is oxidized over microwave absorbing solid catalyst. In the second, the direct absoption of microwaves by carbon is used to drive the highly energy intensive carbon-steam reaction for the production of synthesis gas. Our initial catalytic studies focused on oxidation reactions that fit two criteria. One is that they are of interest as pathways to industrially important commodity or fine chemicals. The second is that there is some literature precedent that suggests that oxides such as spinels will catalyze these transformations. In the former system we have developed microwave specific catalysts materials based on magnetic spinel oxides to accomplish difficult oxidation processes. For the particular system of chromite spinels of the general form MCr2O4 (M=Fe2+, Co2+, Cu2+) we were able to oxidize methanol to formaldehyde in aqueous solutions under very mild conditions. In our studies of the carbon-steam reaction, which is the primary reaction in coal gasification, we identified a reaction that is driven thermally at high temperatures whose reactants are strongly microwave absorbing. In this study our objective was to heat the reagents using microwave irradiation in order to drive the reaction at a lower temperature than traditional heating methods. We are able to directly heat the carbon to temperatures at which it reacts with steam (also generated using the microwaves) to produce synthesis gas (CO + H2). In our work we observe that microwave heating contributes to increased reaction rates, which in one case is attributed to efficient heating and in the other case a "microwave effect". Microwave heating is underutilized by the scientific community. With the possibility of realizing a microwave effect and the assurance of highly efficient heating, researchers should consider using microwave heating as a possible substitute to the traditional convective heating that is used in many labs., Submitted Note: A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Summer Semester, 2012., Date of Defense: June 19, 2012., Keywords: catalysis, gasification, microwave, Bibliography Note: Includes bibliographical references., Advisory Committee: Albert Stiegman, Professor Directing Dissertation; Jeff Chanton, University Representative; John Dorsey, Committee Member; Alan G. Marshall, Committee Member.
Low Voltage Ride-through for Photovoltaic Systems Using Finite Control-Set Model Predictive Control
Low Voltage Ride-through for Photovoltaic Systems Using Finite Control-Set Model Predictive Control
Grid codes impose immunity requirements to the generation systems that are connected to the transmission lines. Immunity refers to the generator’s capability to overcome grid abnormal conditions. One of the requirements is to remain connected during a certain time when a fault, like voltage sag, is presented. During the fault scenario, a generator unit should remain connected for a pre-determined amount of time, and also provide reactive power to support the grid voltage. This is called low-voltage ride through (LVRT). Initially, LVRT requirements were imposed for large generator units like wind farms connected to the transmission network; however, due to the increased penetration of distributed generation (DG) on the distribution system, new grid codes extend the mentioned capability to generator units connected to the distribution grid. Due to matured photovoltaic (PV) technology and the decreased price of PV panels, PV grid tied installations are proliferating in the utility grids; this is creating new challenges related to voltage control. In the past, DG such as PV were allowed to trip from the grid when a fault or unbalance occurred and reconnect within several seconds (sometimes minutes) once the fault had been cleared. Nevertheless, thanks to high PV penetration nowadays, the same method cannot be used because it will further deteriorate the power quality and potentially end in a power blackout. Different approaches have been considered to fulfill the LVRT requirement on PV systems. A large amount of literature focuses on the control of the grid side converter of the PV installation rather than the control of PV operation during the fault, and most control designs applied to the grid side follow classical control methods. Moreover, the effects of the grid fault on the generator side impose a challenge for controlling the PV systems since the quality of the synthesized converter voltages and currents depends on the dc link power/voltage control. This document proposes a Model based Predictive Control (MPC) for controlling a two stage PV system to fulfill LVRT requirements. MPC offers important advantages over traditional linear control strategies since the MPC cost function can include constraints that are difficult to achieve in classical control. Special attention is given to implementation of the proposed control algorithms. Simplified MPC algorithms that do not compromise the converter performance and immunity requirement are discussed., Submitted Note: A Dissertation submitted to the Department of Electrical and Computer Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Summer Semester 2017., Date of Defense: July 21, 2017., Keywords: LVRT, MPC, Photovoltaic, Renewable Energies, Voltage support, Bibliography Note: Includes bibliographical references., Advisory Committee: Chris S. Edrington, Professor Directing Dissertation; Juan Ordonez, University Representative; Omar Faruque, Committee Member; Simon Y. Foo, Committee Member.
Low-Cost Concentrating Solar Collector for Steam Generation
Low-Cost Concentrating Solar Collector for Steam Generation
Concentrating solar power (CSP) is a unique renewable energy technology. CSP systems have the ability to provide electricity, refrigeration and water purification in one unit. This technology will be extremely helpful in improving the quality of life for many people around the world who lack the energy needed to live a healthy life. An economic parabolic dish concentrating system was built at the Sustainable Energy Science and Engineering Center (SESEC) at Florida State University in Tallahassee, Florida. The goal of the project was to provide 6.67 kW of thermal energy. This is the amount of energy required to produce 1 kW of electricity with a conventional micro steam turbine. The system had a price goal of $1000 per kW and must be simple enough to be maintained by non-technical personnel. A 14 m^2 fiberglass parabolic concentrator was made at SESEC to ensure simplicity of production and operation. The concentrator was coated with a highly reflective polymer film. The cavity type receiver was filled with sodium nitrate to act as a heat storage and transfer medium. The collection efficiency of the cavity was estimated at 70%. The gross thermal conversion efficiency of the system was 39%, which represented a 333% improvement over the first concentrator assembled at SESEC. At peak insolation 5.46 kW of thermal energy was produced. The material cost for the system was $3,052., Submitted Note: A Thesis submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Master of Science., Degree Awarded: Degree Awarded: Spring Semester, 2009., Date of Defense: Date of Defense: March 26, 2009., Keywords: Solar Thermal Collector, Aborber, Tilt Angle, Receiver Cavity Optimization, Bibliography Note: Includes bibliographical references., Advisory committee: Anjaneyulu Krothapalli, Professor Directing Thesis; Brenton Greska, Committee Member; Juan Carlos Ord´o˜nez, Committee Member; William S. Oates, Committee Member.
Low-Cost-Solar Liquid Desiccant System for Residential Cooling
Low-Cost-Solar Liquid Desiccant System for Residential Cooling
The use of liquid desiccants for dehumidification of heating, ventilation, and air conditioning (HVAC) process air is becoming a more promising concept as the drive for energy conservation continues to grow. Recently, liquid desiccant systems have been implemented on the commercial level in conjunction with evaporative coolers and have recorded energy savings upwards of 50%. The aim of this research is to test the potential liquid desiccant systems have on the residential level when paired with a conventional vapor compression cycle and to construct a system that would overcome some of its barriers to the residential market. A complete low-cost-solar liquid desiccant system was designed, constructed, and tested in the Off-Grid Zero Emissions Building (OGZEB) at the Florida State University. Key design characteristics include turbulent process air flow through the conditioner and airside heating in the regenerator. The system was tested in the two following ways: (1) for the energy savings while maintaining a constant temperature over a twenty four hour period and (2) for the energy savings over a single cooling cycle. The liquid desiccant system achieved a maximum energy savings of 38% over a complete day and 52% over a single cooling cycle. It was projected that the system has the potential to save 1064 kWh over the course of a year. When combined with a renewable source of heat for regeneration, liquid desiccant systems become very cost effective. The levelized cost of energy for the combination of the liquid desiccant system and solar thermal collectors was calculated to be 7.06 [Cedi Sign]/kWh with a payback period of 4.4 years. This research provides evidence of the technology's potential on the residential sector and suggests ways for it to become competitive in the market., Submitted Note: A Thesis submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Master of Science., Degree Awarded: Spring Semester, 2013., Date of Defense: January 10, 2013., Keywords: Cooling, Energy, High Performance Building, HVAC, Liquid Desiccant, Solar, Bibliography Note: Includes bibliographical references., Advisory Committee: Anjaneyulu Krothapalli, Professor Directing Thesis; Juan Ordóñez, Committee Member; Patrick Hollis, Committee Member.
Low-Frequency Minimum Temperature Variability Throughout the Southeastern United States during the 1970s
Low-Frequency Minimum Temperature Variability Throughout the Southeastern United States during the 1970s
The low-frequency signals (LFS) of climate variables such as temperature and pressure often contain variability as a result of the nonlinear and non-stationary nature of Earth's climate system. Occasionally, as in the case of the North Pacific climate regime shift of the mid-1970s, this variability appears in the form of an abrupt shift in climate states. Because such variability can have large impacts on agriculture, wildfire frequency/intensity, and ecological systems, it is important to pursue a more complete understanding of low frequency climate interactions. Previously, techniques such as fourier, windowed fourier, and wavelet analyses were used to extract the LFS. However, these techniques rely on an assumption of linearity, and thus when applied to nonlinear climate data, can potentially cloud the physical meaning of the extracted LFS. In this study a recently developed adaptive and temporally local analysis method—ensemble empirical mode decomposition (EEMD)—is applied to extract the LFS from observed daily minimum temperature data. The analysis uses data from 115 weather stations scattered throughout North Carolina, South Carolina, Georgia, Alabama, and Florida for the period from 1955 through 2007. An EOF analysis of the minimum temperature LFS reveals a large drop in the first PC time series in the mid-1970s. Further EOF-based analysis of the low-frequency variability leads to different interpretations of the characteristics of surface temperature variability. Most notably, the widely recognized shift of low-frequency variability around the mid-1970s can be alternatively interpreted in the Southeastern United States as phase coincidence between individual quasi-oscillatory components of interannual to decadal timescales., Submitted Note: A Thesis Submitted to the Department of Earth Ocean and Atmospheric Science in Partial Fulfillment of the Requirements for the Degree of Master of Science., Degree Awarded: Spring Semester, 2011., Date of Defense: March 21, 2011., Keywords: Low-frequency variability, Climate variability, Climate regime, Bibliography Note: Includes bibliographical references., Advisory committee: Zhaohua Wu, Professor Directing Thesis; Vasu Misra, Committee Member; Philip Sura, Committee Member.
Low-Frequency Variations of the Sea Breeze in Florida
Low-Frequency Variations of the Sea Breeze in Florida
The variations in the sea breeze are examined both diurnally and interannually along the panhandle of Florida during the boreal summer season. A climatology of sea breeze cross sections is calculated eight times daily between the years 1979 and 2001 to examine diurnal differences. The cross sections are created using very high resolution dynamically downscaled analyses from the NCEP-DOE (R2) and the ECMWF ERA-40 for the southeast U.S. The high resolution downscaled product is validated with other independent observations to show fidelity. Results from these diurnal analyses show that the sea breeze and precipitation peak at 4:00 p.m. The interannual variability of the sea breeze is examined with respect to the Atlantic Warm Pool (AWP). Composites consisting of Climate Prediction Center (CPC) precipitation observations are created based on the size of the AWP. These composites show that the strongest low-frequency signal is a negative anomaly along the panhandle. Therefore, model composite cross sections are primarily along the 30.5°N latitude. The cause of the negative anomaly is related to the subtropical high, which undergoes an eastward shift and a decrease in intensity for large AWP years. These changes in the subtropical high lead to a more cyclonic large-scale low-level flow for large AWP years as Sverdrup vorticity balance indicates. This study finds that this synoptic flow pattern will suppress the sea breeze circulation and lessen precipitation amounts over the panhandle region., Submitted Note: A Thesis Submitted to the Department of Earth, Ocean, and Atmospheric Science in Partial Fulfillment of the Requirements for the Degree of Master of Science., Degree Awarded: Summer Semester, 2011., Date of Defense: April 28, 2011., Keywords: Bermuda High, Atlantic Warm Pool, Sverdrup Vorticity Balance, interannual variations, Bibliography Note: Includes bibliographical references., Advisory Committee: Vasubandhu Misra, Professor Directing Thesis; James J. O’Brien, Professor Co-Directing Thesis; Henry Fuelberg, Committee Member; Mark Bourassa, Committee Member.
Low-Income African American Parents' Views About the Value of Play for Their Preschool Age Children in Head Start
Low-Income African American Parents' Views About the Value of Play for Their Preschool Age Children in Head Start
This qualitative study was conducted to acquire a description of low income African American mother's beliefs about play's relationship with cognitive development. African American mothers of preschool children attending a Head Start program in the central region of Florida were recruited. Parental beliefs were explored through a semi-structured interview to gain insight regarding play's impact on language development, critical thinking, and social competency. Head Start was selected based on being an established national federally funded program for low income families. Overall, the sample of low-income mothers held very positive views on the value of play for cognitive development. They believed that play may be essential for young children's development in social interactions, creativity, problem solving, and other areas that contribute to kindergarten readiness., Submitted Note: A Dissertation Submitted to the Department of Family and Child Sciences in the Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy., Degree Awarded: Fall Semester, 2009., Date of Defense: October 30, 2009., Keywords: African American, Low-Income, Beliefs, Play, Preschool, Head Start, Bibliography Note: Includes bibliographical references., Advisory Committee: Marsha Rehm, Professor Directing Dissertation; Mary Francis Hanline, University Representative; Christine Readdick, Committee Member.
Low-Rank Riemannian Optimization Approach to the Role Extraction Problem
Low-Rank Riemannian Optimization Approach to the Role Extraction Problem
This dissertation uses Riemannian optimization theory to increase our understanding of the role extraction problem and algorithms. Recent ideas of using the low-rank projection of the neighborhood pattern similarity measure and our theoretical analysis of the relationship between the rank of the similarity measure and the number of roles in the graph motivates our proposal to use Riemannian optimization to compute a low-rank approximation of the similarity measure. We propose two indirect approaches to use to solve the role extraction problem. The first uses the standard two-phase process. For the first phase, we propose using Riemannian optimization to compute a low-rank approximation of the similarity of the graph, and for the second phase using k-means clustering on the low-rank factor of the similarity matrix to extract the role partition of the graph. This approach is designed to be efficient in time and space complexity while still being able to extract good quality role partitions. We use basic experiments and applications to illustrate the time, robustness, and quality of our two-phase indirect role extraction approach. The second indirect approach we propose combines the two phases of our first approach into a one-phase approach that iteratively approximates the low-rank similarity matrix, extracts the role partition of the graph, and updates the rank of the similarity matrix. We show that the use of Riemannian rank-adaptive techniques when computing the low-rank similarity matrix improves robustness of the clustering algorithm., Submitted Note: A Dissertation submitted to the Department of Mathematics in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Fall Semester 2017., Date of Defense: September 21, 2017., Keywords: blockmodeling, graph partitioning, networks, Riemannian optimization, role extraction problem, Bibliography Note: Includes bibliographical references., Advisory Committee: Kyle A. Gallivan, Professor Co-Directing Dissertation; Paul Van Dooren, Professor Co-Directing Dissertation; Gordon Erlebacher, University Representative; Giray Ökten, Committee Member; Mark Sussman, Committee Member.
Lower Glass Ceiling
Lower Glass Ceiling
Background and Purpose. For many individuals experiencing homelessness, formal employment is paramount to housing stability. Women represent one of the fastest growing segments of the homeless population; however, there are no recent studies on employment for women unaccompanied by children while experiencing homelessness. Research has established barriers to employment faced by women experiencing homelessness, such as domestic violence, substance use, and mental illness; however, these studies focus on women accompanied by children. This dissertation addresses the following research question: What factors influence employment status among unaccompanied women experiencing homelessness? Methodology. I used mixed methodology to address the research question, comparing findings from secondary data analysis to qualitative interviews. First, I used a cross-sectional sample of 1,331 unaccompanied women in one city’s Homeless Management Information System (HMIS). I used logistic regression to assess the impact age, race, domestic violence, homeless episodes, mental illness, substance abuse, and physical health had on employment status. Next, I completed twenty in-depth, semi-structured interviews with a subsample of unaccompanied women recruited from emergency or transitional housing in the area. Interviews focused on women’s experiences in employment and their biggest perceived barriers to finding or maintaining employment while homeless. Interviews were transcribed verbatim and coded thematically using NVivo11 software. Finally, I organized barriers identified in the qualitative interviews in a content analysis and compared the results to the logistic regression. Findings. None of the variables reached statistical significance in the logistic regression. Qualitative analysis showed that women generally had limited formal employment experience, based their future employment plans on previous employment experiences, and were in a holding pattern between training programs and limited employment opportunities. Women reported differing perceptions about barriers to employment, but the majority of women did mention the same four barriers: stigma against homelessness, transportation, physical health, and being presentable for job activities. While many interview participants disclosed histories of substance use, mental illness, and domestic violence, most women reported these factors did not directly affect employment, although women reported these factors did contribute to homelessness. Physical health was the only barrier included in the regression model and identified by women in interviews as a top barrier to work, however it was not statistically significant in the regression model. Conclusion and Implications. While the quantitative findings did not reach statistical significance, the comparison of the quantitative and qualitative results indicated important areas for future research and data collection efforts, such as measures for new measures employment and further research on the relationship between physical health and employment. The qualitative findings support the available literature regarding the importance of stigma, transportation, and physical presentation among unaccompanied women experiencing homelessness. Physical health may be an important personal-level barrier to employment for unaccompanied women experiencing homelessness, particularly when it comes to seeking full time employment. Implications for practice and policy include community stigma reduction, interventions development to increase formal employment in skilled positions, and modifying housing program policies to reduce burden on women with employment., Submitted Note: A Dissertation submitted to the College of Social Work in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Summer Semester 2017., Date of Defense: June 29, 2017., Keywords: employment, homelessness, mixed methodology, women, Bibliography Note: Includes bibliographical references., Advisory Committee: Melissa Radey, Professor Directing Dissertation; Lenore McWey, University Representative; Jean Munn, Committee Member; Dina Wilke, Committee Member.
Lowest ℓ = 0 Proton Resonance in Si-26 and Its Implications for the Stellar Nucleosynthesis of Al-26.
Lowest ℓ = 0 Proton Resonance in Si-26 and Its Implications for the Stellar Nucleosynthesis of Al-26.
Determining the stellar production site of 26Al is an exciting problem that spans experimental and theoretical nuclear physics, astrophysics, and observational astronomy. This thesis details an experiment to measure the 25Al(d,n)26Si single proton transfer reaction, which can provide information on the astrophysically significant 25Al(p,gamma)26Si reaction. The first 3+ state in 26Si, which is predicted to dominate the stellar nucleosynthesis rate, was observed and characterized. The implications for stellar nucleosynthesis are discussed for potential stellar production sites., Submitted Note: A Dissertation Submitted to the Department of Physics in Partial FulfiLlment of the Requirements for the Degree of Doctor of Philosophy., Degree Awarded: Spring Semester, 2009., Date of Defense: March 3, 2009., Keywords: Nuclear Physics, 26Al, Al-26, 26Si, Si-26, Galactic Al-26 Distribution, Radioactive Ion Beam, Al-25, 25Al, Rapid Proton Process, rp-process, Classical Nova, Core Collapse Supernova, Nova, Supernova, Bibliography Note: Includes bibliographical references., Advisory Committee: Ingo Wiedenhöver, Professor Directing Dissertation; Henry Fuelberg, Outside Committee Member; Alexander Volya, Committee Member; Grigory Rogachev, Committee Member; Peter Höflich, Committee Member.
Lubbock I Carry
Lubbock I Carry
The poems in The Lubbock I Carry primarily operate according to traditional free-verse poetic convention, working to render, as a means of both illumination and interrogation, the emotional and physical landscapes of the past, how they not only inform but actually mold identity through language, cultural referents (and expectations), and terrain., Submitted Note: A Dissertation submitted to the Department of English in partial fulfillment of the Doctor of Philosophy., Degree Awarded: Spring Semester 2017., Date of Defense: February 27, 2017., Keywords: poetry, Bibliography Note: Includes bibliographical references., Advisory Committee: James Kimbrell, Professor Directing Dissertation; Juan Carlos Galeano, University Representative; Ned Stuckey-French, Committee Member; David Kirby, Committee Member; Andrew Epstein, Committee Member.
Lucan "Transforms" Ovid
Lucan "Transforms" Ovid
Although many of Lucan's allusions to Ovid are well-known, studies which contextualize them with the care that has been done with, e.g., Lucan and Vergil are still few in number. My goal in this study is to make a substantial contribution to the growing understanding of Ovid's influence upon Lucan. In seeking to move beyond the emulation-alone model as a way of explaining their poetic interactions, I examine a number of intertextual links between Lucan's Bellum Civile and Ovid's Metamorphoses, and I demonstrate how Lucan appropriates Ovidian material to articulate and enhance his broader poetic goals and vision., Submitted Note: A Dissertation submitted to the Department of Classics in partial fulfillment of the requirements for the degree of Doctor of Philosophy., Degree Awarded: Spring Semester, 2012., Date of Defense: March 15, 2012., Keywords: Allusion, Bellum Civile, Intertextuality, Lucan, Metamorphoses, Ovid, Bibliography Note: Includes bibliographical references., Advisory Committee: Laurel Fulkerson, Professor Directing Dissertation; David Levenson, University Representative; Francis Cairns, Committee Member; Timothy Stover, Committee Member.

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