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Mechanical Study On Edge-Oxidized Graphene Oxide (Eogo) Reinforced Concrete, Mohammad Khawaji Jan 2019

Mechanical Study On Edge-Oxidized Graphene Oxide (Eogo) Reinforced Concrete, Mohammad Khawaji

Electronic Theses and Dissertations

It is known that graphene oxide (GO) has superior mechanical properties and can enhance mechanical properties of cement composites. However, Hummer produced conventional GOs have been limited to small-scale specimens (e.g., cement paste and mortar) and applications to concrete have not been implemented due to their high cost and large volume of concrete. Edge-oxidized graphene oxide (EOGO) is a low-cost, carbon-based nanomaterial produced by a mechanochemical process with ball milling and a non-toxic oxidizing agent. The low cost (less than $50/kg) of EOGO enables its use in bulk-scale concrete materials/structures, which is a prerequisite for the field implementation. In this …


Enhanced Concrete Bridge Assessment Using Artificial Intelligence And Mixed Reality, Enes Karaaslan Jan 2019

Enhanced Concrete Bridge Assessment Using Artificial Intelligence And Mixed Reality, Enes Karaaslan

Electronic Theses and Dissertations

Conventional methods for visual assessment of civil infrastructures have certain limitations, such as subjectivity of the collected data, long inspection time, and high cost of labor. Although some new technologies (i.e. robotic techniques) that are currently in practice can collect objective, quantified data, the inspector's own expertise is still critical in many instances since these technologies are not designed to work interactively with human inspector. This study aims to create a smart, human-centered method that offers significant contributions to infrastructure inspection, maintenance, management practice, and safety for the bridge owners. By developing a smart Mixed Reality (MR) framework, which can …


Investigation Of Coastal Vegetation Dynamics And Persistence In Response To Hydrologic And Climatic Events Using Remote Sensing, Subrina Tahsin Jan 2019

Investigation Of Coastal Vegetation Dynamics And Persistence In Response To Hydrologic And Climatic Events Using Remote Sensing, Subrina Tahsin

Electronic Theses and Dissertations

Coastal Wetlands (CW) provide numerous imperative functions and provide an economic base for human societies. Therefore, it is imperative to track and quantify both short and long-term changes in these systems. In this dissertation, CW dynamics related to hydro-meteorological signals were investigated using a series of LANDSAT-derived normalized difference vegetation index (NDVI) data and hydro-meteorological time-series data in Apalachicola Bay, Florida, from 1984 to 2015. NDVI in forested wetlands exhibited more persistence compared to that for scrub and emergent wetlands. NDVI fluctuations generally lagged temperature by approximately three months, and water level by approximately two months. This analysis provided insight …


A Study Of Perceptions On Incident Response Exercises, Information Sharing, Situational Awareness, And Incident Response Planning In Power Grid Utilities, Joseph Garmon Jan 2019

A Study Of Perceptions On Incident Response Exercises, Information Sharing, Situational Awareness, And Incident Response Planning In Power Grid Utilities, Joseph Garmon

Electronic Theses and Dissertations

The power grid is facing increasing risks from a cybersecurity attack. Attacks that shut off electricity in Ukraine have already occurred, and successful compromises of the power grid that did not shut off electricity to customers have been privately disclosed in North America. The objective of this study is to identify how perceptions of various factors emphasized in the electric sector affect incident response planning. Methods used include a survey of 229 power grid personnel and the use of partial least squares structural equation modeling to identify causal relationships. This study reveals the relationships between perceptions by personnel responsible for …


The Path Of A Stressed Temporary Worker To Cwb, Jamie Striler Jan 2019

The Path Of A Stressed Temporary Worker To Cwb, Jamie Striler

Electronic Theses and Dissertations

Temporary workers may experience unique and oftentimes stressful work situations that can precipitate negative outcomes for these workers, their coworkers, and their organizations. The current study considered broader implications of the various work experiences among temporary workers by testing the relationships of workplace stressors to temporary workers' behaviors. The workplace stressors examined were chosen based on their salience to temporary workers as shown throughout the current temporary worker literature, and included economic stressors, interpersonal mistreatment, and organizational constraints. It was hypothesized that these stressors would predict temporary workers' behaviors via emotional exhaustion and moral disengagement pathways, predicting the performance of …


Compressible Turbulent Reactions For Hypersonic Propulsion Applications, Jonathan Sosa Jan 2019

Compressible Turbulent Reactions For Hypersonic Propulsion Applications, Jonathan Sosa

Electronic Theses and Dissertations

This work presents the first measurement of turbulent burning velocities of a highly-turbulent compressible standing flame induced by shock-driven turbulence in a Turbulent Shock Tube. High-speed schlieren, chemiluminescence, PIV, and dynamic pressure measurements are made to quantify flame-turbulence interaction for high levels of turbulence at elevated temperatures and pressure. Distributions of turbulent velocities, vorticity and turbulent strain are provided for regions ahead and behind the standing flame. The turbulent flame speed is directly measured for the high-Mach standing turbulent flame. From measurements of the flame turbulent speed and turbulent Mach number, transition into a non-linear compressibility regime at turbulent Mach …


Shock Tube Investigations Of Novel Combustion Environments Towards A Carbon-Neutral Future, Samuel Barak Jan 2019

Shock Tube Investigations Of Novel Combustion Environments Towards A Carbon-Neutral Future, Samuel Barak

Electronic Theses and Dissertations

Supercritical carbon dioxide (sCO2) cycles are being investigated for the future of power generation. These cycles will contribute to a carbon-neutral future to combat the effects of climate change. These direct-fired closed cycles will produce power without adding significant pollutants to the atmosphere. For these cycles to be efficient, they will need to operate at significantly higher pressures (e.g., 300 atm for Allam Cycle) than existing systems (typically less than 40 atm). There is limited knowledge on combustion at these pressures or at the high dilution of carbon dioxide. Nominal fuel choices for gas turbines include natural gas and syngas …


Probing The Influence Of Cx43 And Glucose On Endothelial Biomechanics, Md Mydul Islam Jan 2019

Probing The Influence Of Cx43 And Glucose On Endothelial Biomechanics, Md Mydul Islam

Electronic Theses and Dissertations

Endothelial cells (ECs) form the innermost layer of all vasculature and constantly receive both biochemical and biomechanical signals, yielding a plethora of biomechanical responses. In response to various biochemical or biomechanical cues, ECs have been documented to generate biomechanical responses such as tractions and intercellular stresses between the cell and substrate and between adjacent cells in a confluent monolayer, respectively. Thus far, the ability of endothelial tight junctions and adherens junctions to transmit intercellular stresses has been actively investigated, but the role of gap junctions is currently unknown. In addition, there is no report of the independent influence of hyperglycemia …


Linear Systems With Integral Constraints On Transient Step-Response, Bilal Salih Jan 2019

Linear Systems With Integral Constraints On Transient Step-Response, Bilal Salih

Electronic Theses and Dissertations

The topic of shaping and controlling transient responses of dynamic systems has important applications. Achieving a desired transient response is an essential design requirement for many control system. In this research, we discuss the impact on the transient response of linear systems when it is subjected to a set of integral constraints. The investigation is generalized in a theoretical framework. Formulation of three types of integral constraints is first discussed. The underlying goal of the problem is to shape the step response to generate a specific type of transient response which in turn satisfies the desired integral constraints. The problem …


Integration Of Computational Fluid Dynamics And Machine Learning For Modeling Scaffold Pore Structure For Tissue Engineering, Amir Rouhollahi Jan 2019

Integration Of Computational Fluid Dynamics And Machine Learning For Modeling Scaffold Pore Structure For Tissue Engineering, Amir Rouhollahi

Electronic Theses and Dissertations

Freeze-casting is a popular method to produce biomaterial scaffolds with highly porous structures. Three approaches are developed to predict the scaffold pore structure as function of experimental conditions including mold geometry, material and thermal boundary conditions. First, a mathematical model integrating Computational Fluid Dynamics (CFD) with Population Balance Model is developed to predict average pore size (APS) of 3D porous chitosan alginate scaffolds and to assess the influence of the geometrical parameters of mold on scaffold pore structure. The model predicted the crystallization pattern and APS for scaffolds cast in different diameter molds and filled to different heights. The predicted …


Identity And Second Language Acquisition: Adult Puerto Rican Migrants Living In The United States, Marcio Rubens Soares Gomes Jan 2019

Identity And Second Language Acquisition: Adult Puerto Rican Migrants Living In The United States, Marcio Rubens Soares Gomes

Electronic Theses and Dissertations

Drawing on the poststructuralist construct of identity and on Norton's (1995) concept of investment, as well as on Bourdieu's (1977) notion of capital, this qualitative research study relies on data gathered through interviews conducted with two adult female participants from Puerto Rico, who migrated to Central Florida approximately ten years ago. It aims at answering the following questions: (i) what identity-related factors facilitate or hinder the acquisition of the target language by Puerto Rican migrants? (ii) what social forces or barriers impact learning ESL in the context of Puerto Rican migration to the United States? The findings indicate that investment …


El Silencio Literario Como Artificio Narrativo En Pedro Paramo De Juan Rulfo, Florilde Rodriguez Jan 2019

El Silencio Literario Como Artificio Narrativo En Pedro Paramo De Juan Rulfo, Florilde Rodriguez

Electronic Theses and Dissertations

This work exposes the narrative silence as the main enunciator of the textual discourse in Juan Rulfo's novel, Pedro Paramo. Through a sociological reading, the literary silences comprised in the events are interpreted to access one of the multiple possible meanings of the story. The study inserts ideas, historical facts and human, social, psychological and material factors in the openings left by the author, thus producing a discourse that shapes the manifesto of contemporary life.


The Feminine Margin: The Re-Imagining Of One Professor's Rhetorical Pedagogy--A Curriculum Project, Camila Alvarez Jan 2019

The Feminine Margin: The Re-Imagining Of One Professor's Rhetorical Pedagogy--A Curriculum Project, Camila Alvarez

Electronic Theses and Dissertations

Writing pedagogy uses techniques that institutionalize dichotomous thinking rather than work against it. Cartesian duality has helped to create the marginalization of people, environments, and animals inherent in Western thought. Writing pedagogy based in current-traditional rhetoric uses a writing process that reinforces the hierarchical structure of Self/Other, Author/Reader, and Teacher/Student. This structure, in conjunction with capitalism, prioritizes the self and financial gain while diminishing and objectifying the other. The thought process behind the objectification and monetization of the other created the unsustainable business and life practices behind global warming, racism, sexism, and environmental destruction. A reframing of pedagogical writing practices …


Waking Up White: The Search For Black Happiness, Jason Gregory Jan 2019

Waking Up White: The Search For Black Happiness, Jason Gregory

Electronic Theses and Dissertations

Waking Up White (WUW) is a television pilot written, directed and co-produced by Jason D. Gregory serving as part of his thesis requirements for earning a Master of Fine Arts in the Entrepreneurial Digital Cinema program at the University of Central Florida. The project attempts to answer the question "what if" by placing the main characters in a "fish out of water" scenario. In WUW a Black family wakes up White and has 30 days to determine if they'd rather return to their cultural roots or stick with the "new skin" that they are in. Upon awakening to their new …


How Change Started To Come: Examining Rhythm And Blues And Southern Identity, Jennifer Davis Jan 2019

How Change Started To Come: Examining Rhythm And Blues And Southern Identity, Jennifer Davis

Electronic Theses and Dissertations

This project seeks a better understanding on how blackness has been peripheral to our understanding of the term Southerner. The purpose of this work is to examine an area where the intersection of race and region exists to more fully understand how blacks in the South have presented their sense of Southern identity. The chosen area of examination is the music of rhythm and blues. Rhythm and blues as a genre rose to prominence in the years following World War II. The main reason for analyzing rhythm and blues as an intersecting point of race and region is that the …


Making Our Voices Heard: Power And Citizenship In Central Florida's Black Communities, Gramond Mcpherson Jan 2019

Making Our Voices Heard: Power And Citizenship In Central Florida's Black Communities, Gramond Mcpherson

Electronic Theses and Dissertations

This thesis examines the impacts of government policies on community mobilization in Orlando's Parramore neighborhood and the all-black town of Eatonville in Central Florida. The scope of this thesis covers the history of both communities from their formation in the 1880s to the end of the twentieth century. This research reveals the relationships between the predominantly black residents of Parramore and Eatonville and the largely white government officials over the development and maintenance of each community. By understanding the social creation of both communities during the era of Jim Crow, this thesis reveals the differing levels of power each community …


The Redeemed, The Condemned, And The Forgotten: Narratives Of Dissenting Aristocratic Identity In Medieval Bavaria, Luke Bohmer Jan 2019

The Redeemed, The Condemned, And The Forgotten: Narratives Of Dissenting Aristocratic Identity In Medieval Bavaria, Luke Bohmer

Electronic Theses and Dissertations

Identity in the Middle Ages encompassed numerous methods of transmission. Those of which that survive today include artwork, architecture, and written sources. In the case of written sources, the nobility and the clergy dominated the narrative to a substantial degree. Chroniclers of the Holy Roman Empire in specific saw both regional and pan-imperial narratives influence this identity through the exploration of historical figures. The medieval duchy of Bavaria fell into this milieu but experienced a substantially different relationship with its nobility from the twelfth century onward. The more condensed and consolidated format of medieval Bavaria under the Wittelsbach dynasty – …


The Ideal King: Brian Boru And The Medieval European Concept Of Kingship, Kody Whittington Jan 2019

The Ideal King: Brian Boru And The Medieval European Concept Of Kingship, Kody Whittington

Electronic Theses and Dissertations

When one thinks of great kings, and more specifically of great kings of the early medieval period, there are a few names that almost immediately come to mind. Charlemagne is perhaps the first great medieval ruler one may mention. Alfred the Great would likely not be far behind. Both these men represented, for their respective peoples, what a great king should be. The early medieval period was a time of development in thought and in practice for the office of kingship, and the writings and actions of the men of this period would have a profound influence in the following …


Civil War Memory And The Preservation Of The Olustee Battlefield, Steven Trelstad Jan 2019

Civil War Memory And The Preservation Of The Olustee Battlefield, Steven Trelstad

Electronic Theses and Dissertations

This thesis explores the absence of a Union monument at the Olustee Battlefield one hundred and fifty-five years after the battle concluded though this field has a number of Confederate monuments. Moreover, after the Battle of Olustee in February 1864, the largest battle of the Civil War fought on Florida soil, the victorious Confederates killed wounded African American soldiers left behind after the Union retreat. This thesis examines why Olustee battlefield became a place of Confederate memory, enshrining the Lost Cause within its monuments for well over a half of a century that consciously excluded any commemoration of the Union …


'A Room Of Their Own': Heritage Tourism And The Challenging Of Heteropatriarchal Masculinity In Scottish National Narratives, Carys O'Neill Jan 2019

'A Room Of Their Own': Heritage Tourism And The Challenging Of Heteropatriarchal Masculinity In Scottish National Narratives, Carys O'Neill

Electronic Theses and Dissertations

This thesis explores the visibility of women in traditionally masculine Scottish national narratives as evidenced by their physical representation, or lack thereof, in the cultural heritage landscape. Beginning with the 1707 Act of Union between Scotland and England, a moment cemented in history, literature, and popular memory as the beginning of a Scottish rebirth, this thesis traces the evolution of Scottish national identity and the tropes employed for its assertion to paint a clearer picture of the power of strategic selectivity and the effects of sacrifice in the process of community definition. Following the transformation of the rugged Celtic Highlander …


Color-Ratio Based Strawberry Plant Localization And Nutrition Deficiency Detection, Xiangling Kong Jan 2019

Color-Ratio Based Strawberry Plant Localization And Nutrition Deficiency Detection, Xiangling Kong

Electronic Theses and Dissertations

In recent years, precision agriculture has become popular anticipating to partially meet the needs of an ever-growing population with limited resources. Plant localization and nutrient deficiency detection are two important tasks in precision agriculture. In this dissertation, these two tasks are studied by using a new color-ratio(C-R) index technique. Firstly, a low cost and light scene invariant approach is proposed to detect green and yellow leaves based on the color-ratio (C-R) indices. A plant localization approach is then developed using the relative pixel relationships of adjacent plants. Secondly, the Sobel operator and morphology techniques are applied to segment the target …


Cavitation And Heat Transfer Over Micro Pin Fins, Arash Nayebzadeh Jan 2019

Cavitation And Heat Transfer Over Micro Pin Fins, Arash Nayebzadeh

Electronic Theses and Dissertations

With the dramatic increase in the usage of compact yet more powerful electronic devices, advanced cooling technologies are required to maintain delicate electronic components below their maximum allowable temperatures and prevent them from failure. One solution is to use innovative pin finned heat sinks. This research is centered on the evaluation of hydrodynamic cavitation properties downstream pin fins and extended toward single-phase heat transfer enhancement of array of pin fins in microchannel. In this work, transparent micro-devices capable of local wall temperature measurements were micro fabricated and tested. Various experimental methods, numerical modeling and advanced data processing techniques are presented. …


Interfacial Behavior In Polymer Derived Ceramics And Salt Water Purification Via 2d Mos2, Hao Li Jan 2019

Interfacial Behavior In Polymer Derived Ceramics And Salt Water Purification Via 2d Mos2, Hao Li

Electronic Theses and Dissertations

In the present dissertation, the behavior of the internal potential barrier in a polymer-derived amorphous SiAlCN ceramic was studied by measuring its complex impedance spectra at various dc bias as well as different testing and annealing temperatures. The complex impedance spectra of the polymer-derived a-SiAlCN were measured under various dc bias voltages in a temperature range between 50 and 150°C, as well as different annealing temperatures (1100-1400 °C). All spectra, regardless of temperature and bias, consist of two semi-circular arcs, corresponding to the free-carbon phase and the interface, respectively. The impedance of the free-carbon phase is independent of the bias, …


Disinfection By-Product Formation Potential Assessment For Central Florida Groundwater Supplies, Tulsi Shukla Jan 2019

Disinfection By-Product Formation Potential Assessment For Central Florida Groundwater Supplies, Tulsi Shukla

Electronic Theses and Dissertations

Disinfection of potable water supplies is a primary requirement of the United States' Environmental Protection Agency's (USEPA's) Safe Drinking Water Act. The use of chlorine as a disinfectant is widely accepted by water purveyors due to its effectiveness and low cost. However, chlorine reacts with natural organic matter present in water supplies to form suspected carcinogenic disinfection by-products (DBPs). In this work, the formation of the regulated chlorinated by-products total trihalomethanes (TTHMs) and haloacetic acids (HAA5) for eleven Central Florida wells has been investigated. Fluorescence, UV-254, dissolved organic carbon (DOC), specific UV absorbance (SUVA), chlorine decay, and TTHM and HAA5 …


Detection Of Ddh In Infants And Children Using Audible Acoustics, Tanvir Hassan Jan 2019

Detection Of Ddh In Infants And Children Using Audible Acoustics, Tanvir Hassan

Electronic Theses and Dissertations

Detection of developmental dysplasia of the hip (DDH) in infants and children is important as it leads to permanent hip instability. Current methods for detecting DDH, such as ultrasound and x-rays, are relatively expensive and need qualified medical personnel to administer the test. Furthermore, x-ray ionizing radiation can have potential harmful effects. In the current study, an acoustic non-invasive and simple approach was investigated for detection of DDH. Different benchtop simplified models and pig models were constructed and tested. Models were stimulated with band-limited white acoustic noise (10-2500 Hz) and the response of the models was measured. The power spectrum …


Basic Turbo Roundabouts As An Alternative To Conventional Double-Lane Roundabouts: Operational Performance Evaluation, Zuhair Elhassy Jan 2019

Basic Turbo Roundabouts As An Alternative To Conventional Double-Lane Roundabouts: Operational Performance Evaluation, Zuhair Elhassy

Electronic Theses and Dissertations

Conventional roundabouts have been prevalent worldwide since the emergence of modern roundabouts in 1966. An innovative design of multilane roundabouts known as turbo roundabouts, however, has been recently introduced as an alternative to conventional multilane roundabouts. Due to several reasons, there has been no general consensus on the operational performance of turbo roundabouts throughout the world. Nationwide, turbo roundabouts have yet to be part of roadway systems, but there is an ongoing project expected to be finished in early 2020. Therefore, this dissertation aims to evaluate the operational performance of a widespread variant of turbo roundabouts, namely basic turbo roundabouts, …


Physical-Virtual Patient Simulators: Bringing Tangible Humanity To Simulated Patients, Salam Daher Jan 2019

Physical-Virtual Patient Simulators: Bringing Tangible Humanity To Simulated Patients, Salam Daher

Electronic Theses and Dissertations

In lieu of real patients, healthcare educators frequently use simulated patients. Simulated patients can be realized in physical form, such as mannequins and trained human actors, or virtual form, such as via computer graphics presented on two-dimensional screens or head-mounted displays. Each of these alone has its strengths and weaknesses. I introduce a new class of physical-virtual patient (PVP) simulators that combine strengths of both forms by combining the flexibility and richness of virtual patients with tangible characteristics of a human-shaped physical form that can also exhibit a range of multi-sensory cues, including visual cues (e.g., capillary refill and facial …


Fundamental Properties Of Metallic Nanolasers, William Hayenga Jan 2019

Fundamental Properties Of Metallic Nanolasers, William Hayenga

Electronic Theses and Dissertations

The last two decades have witnessed tremendous advancements in the area of nanophotonics and plasmonics, which has helped propel the development of integrated photonic sources. Of central importance to such circuits is compact, scalable, low threshold, and efficient coherent sources that can be driven at high modulation frequencies. In this regard, metallic nanolasers offer a unique platform. Their introduction has enabled confinement of light at a subwavelength scale and the ultra-small size of the modes afforded by these structures allows for cavity enhancing effects that can help facilitate thresholdless lasing and large direct modulation bandwidths. In this report, I present …


Processing Of Advanced Infrared Materials, Daniel Mcgill Jan 2019

Processing Of Advanced Infrared Materials, Daniel Mcgill

Electronic Theses and Dissertations

Infrared transparent glassy and crystalline materials often have unique and complex processing requirements but are an important class of materials for such applications as optical windows, lenses, waveplates, polarizers and beam splitters. This thesis investigates two specific materials, one amorphous and one crystalline, that are candidates for use in the short and midwave-infrared and mid and longwave infrared, respectively. It is demonstrated that an innovative uniaxial sintering process, which uses a sacrificial pressure-transmitting medium, can be used to fully densify a 70TeO2-20WO3-10La2O3 (TWL) glass powder. The characteristics of the sintered TWL glass is compared to that of a parent glass …


Political Knowledge And Political Engagement In The United States, Brittany Shaul Jan 2019

Political Knowledge And Political Engagement In The United States, Brittany Shaul

Electronic Theses and Dissertations

This thesis examined the impact of political knowledge on forms of political engagement in the United States. Prior literature has established a relationship between political knowledge and political engagement, where those with higher political knowledge were more likely to engage politically through acts such as voting. This study distinguished between the various forms of political engagement and political knowledge, and seeks to provide relevant data on who is more likely to have political knowledge, and what impact having political knowledge has. This served to reexamine trends found in past literature, in order to see if these trends have persisted or …