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Supercritical Co2 Heat Transfer Study Near Critical Point In A Heated Circular Pipe, Akshay Khadse Jan 2020

Supercritical Co2 Heat Transfer Study Near Critical Point In A Heated Circular Pipe, Akshay Khadse

Electronic Theses and Dissertations, 2020-2023

Supercritical CO2 (sCO2) power cycle is an up-and-coming technology to produce electricity from various heat sources. Apart from power cycles, sCO2 can also be used as coolant in centralized cooling system and stand-alone cooling device. However, lack of accurate predication tools such as heat transfer coefficient correlations and insufficient knowledge behind fundamental heat transfer processes can hinder its practical realization in key energy and cooling systems. The overall objective of the study is to extend fundamental knowledge about heat transfer and fluid flow processes in conduits pertinent to sCO2 power cycle. The emphasis here is investigation of heat transfer effects …

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An Investigation In To Resume Construction And Hiring Decisions: Perceptions Of Black Womens Natural Hair, Cassandra Kroon Jan 2020

An Investigation In To Resume Construction And Hiring Decisions: Perceptions Of Black Womens Natural Hair, Cassandra Kroon

Electronic Theses and Dissertations, 2020-2023

This research examined how black women's natural hair was perceived in a professional setting. Expectancy violation theory (EVT) suggests that people create patterns of communication but that these patterns can be disrupted when a person violates the established expectations. The theory was applied to perceptions of black women's natural hair in a professional setting. An experimental survey was used to assess whether participants viewed natural hair in the workplace as a positive or negative expectancy violation. Participants were asked to view a resume and complete Likert-type scale items to evaluate the resume. The items measured the candidate's professionalism, likeability, attractiveness …

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Compressibility Of Fine-Grained Soil In Central Florida, Andre Kruk Jan 2020

Compressibility Of Fine-Grained Soil In Central Florida, Andre Kruk

Electronic Theses and Dissertations, 2020-2023

Fine-grained soils are responsible for most site settlements through a time dependent process known as consolidation. The magnitude of consolidation is quantified with three terms: the recompression and compression indices, referred to as the soil's compressibility indices, and preconsolidation pressure. The ideal methods to estimate these parameters are direct measurements from lab or in-situ field tests, other method include estimation from experience or from correlations to soil parameters. This study refines correlations between compressibility indices and index properties as previously researchers and soil mechanics suggest a strong correlation exists. This study also suggests a correlation to CPT parameters as this …

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A Shock Tube Chemical Kinetic Study Of Ethanol Oxidation At Elevated Pressures, Andrew Laich Jan 2020

A Shock Tube Chemical Kinetic Study Of Ethanol Oxidation At Elevated Pressures, Andrew Laich

Electronic Theses and Dissertations, 2020-2023

Understanding the combustion chemistry of ethanol is critical for continued proliferation and use in future internal combustion engines (ICEs) that will operate in a downsized, turbo-charged, high compression configuration. Detailed chemical kinetic reaction mechanisms already exist for ethanol, which have been validated over a range of operating conditions; however, capturing the conditions that may be seen in future ICEs requires extension of these conditions, namely at elevated pressure. Investigating the kinetics of ethanol existing in a combustion system first involve, for example, understanding a key global metric like ignition delay time (IDT) and measuring major or minor species in a …

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Multi-Parameter Optical Metrology: Quantum And Classical, Walker Larson Jan 2020

Multi-Parameter Optical Metrology: Quantum And Classical, Walker Larson

Electronic Theses and Dissertations, 2020-2023

The insights offered by quantum mechanics to the field of optical metrology are many-fold, with non-classical states of light themselves used to make sensors that surpass the sensitivity of sensors using classical states of light. Unfortunately, this advantage, referred to often as "super-sensitivity" is notoriously fragile, and even the slightest experimental imperfections may greatly reduce the efficacy of the non-classical sensors, sometimes completely obviating their advantage. In my thesis I have shown that the performance of an otherwise ideal two-photon interferometer, which exploits entanglement between photons to make super-sensitive measurements of phase, is crippled by the slightest introduction of decoherence …

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Forests And Farmers: A Landscape Approach To Settlement Pattern Analysis In The Bolivian Amazon, Thomas Lee Jan 2020

Forests And Farmers: A Landscape Approach To Settlement Pattern Analysis In The Bolivian Amazon, Thomas Lee

Electronic Theses and Dissertations, 2020-2023

The Llanos de Mojos of the Bolivian Amazon is a domesticated landscape with a long history of management by pre-Columbian communities. This project uses a landscape approach to interpret the settlement patterns of pre-Columbian raised field farmers in west central Mojos. The pre-Columbian landscape was reconstructed by mapping the distribution of three types of landscape features: forest islands, raised agricultural fields and water systems (rivers, streams & wetlands). Previous research has identified four types of patterned clustering or 'constellations' of these landscape features in west central Mojos. These constellations and the immediate area of the landscape that surrounds them afforded …

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Efforts In Numerical Modeling Of Undulating Propulsion, George Loubimov Jan 2020

Efforts In Numerical Modeling Of Undulating Propulsion, George Loubimov

Electronic Theses and Dissertations, 2020-2023

Naval propulsion is a critical component for every vessel, and it is the subject of this thesis, specifically bio-inspired propulsion. Numerical modeling is used as a tool to understand the relationship between mechanical undulation and the hydrodynamic response. Through three stages, the research presented here examines and refines tools for understanding fundamentals of undulating propulsion. Those three objectives are: to verify and validate the proposed numerical models against existing experiments, establishing a baseline of fidelity; to examine the causal linkage between fluid-boundary interactions and undulating propulsion; and to create a moment based method for characterizing generalized undulating propulsive mechanisms. First, …

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Additive Manufacturing Of Copper-Based Alloy By Laser Powder Bed Fusion, Binghao Lu Jan 2020

Additive Manufacturing Of Copper-Based Alloy By Laser Powder Bed Fusion, Binghao Lu

Electronic Theses and Dissertations, 2020-2023

Copper (Cu) and Cu-alloy are good candidates for the engineered components that require good thermal and electrical conductivity. Since industry often needs sophisticated components that cannot be made easily by traditional methods, such as casting, forging and machining, research for additive manufacturing of copper-based alloy is on demand. Therefore, this thesis focuses on the optimization of laser powder bed fusion (LPBF) of Cu-10 wt.% Sn alloy and pure Cu based on their characteristics such as relative density/porosity, surface roughness, phase constitutes, melt pool dimension, and dendrite arm spacings dimension, determined by optical microscopy, X-ray diffraction and Scanning electron microscope. LPBF, …

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An Examination Of The Quality And Development Of Educational Plans For Gifted Students, David Maddock Jan 2020

An Examination Of The Quality And Development Of Educational Plans For Gifted Students, David Maddock

Electronic Theses and Dissertations, 2020-2023

This two-phase mixed-methods study applied a researcher-created instrument (Education Plan Quality Assessment) to extant documents created by teachers in a single central Florida school district. A true random sample of 337 student educational plans was drawn from a gifted population of 2,370 students. A snowball sample, which utilized the student sample to recruit a teacher sample, was created from teachers who worked on the plans and those teachers were contacted to complete the Opinions about the Gifted and their Education (OGE) opinionnaire which provided teacher opinion scores related to giftedness. Teachers were surveyed as to their opinions of giftedness to …

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Video Content Understanding Using Text, Amir Mazaheri Jan 2020

Video Content Understanding Using Text, Amir Mazaheri

Electronic Theses and Dissertations, 2020-2023

The rise of the social media and video streaming industry provided us a plethora of videos and their corresponding descriptive information in the form of concepts (words) and textual video captions. Due to the mass amount of available videos and the textual data, today is the best time ever to study the Computer Vision and Machine Learning problems related to videos and text. In this dissertation, we tackle multiple problems associated with the joint understanding of videos and text. We first address the task of multi-concept video retrieval, where the input is a set of words as concepts, and the …

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The Position Of An Instructional Literacy Coach: A Case Study Of The Perceptions Of High School Administrators, Classroom Teachers, And Coaches In One Florida School District, Rachel Miracolo Jan 2020

The Position Of An Instructional Literacy Coach: A Case Study Of The Perceptions Of High School Administrators, Classroom Teachers, And Coaches In One Florida School District, Rachel Miracolo

Electronic Theses and Dissertations, 2020-2023

The purpose of this quantitative case study was to examine the position of an instructional literacy coach as perceived by high school administrators, teachers, and coaches in one Florida school district and to determine if any perceptual variance existed among those groups. A problem existed with understanding how the instructional literacy coach position manifested in different school contexts and how that manifestation impacted workplace dynamics. Given the dynamic nature of instructional coaching, this study further explored the level of congruence or incongruence between key faculty groups in order to better understand perceptions of coaching as a professional learning tool. The …

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The Memory Remains: Why The Migration Period And The Fall Of Rome Continue To Be Mischaracterized As A Barbarian Invasion, Walter Napier Jan 2020

The Memory Remains: Why The Migration Period And The Fall Of Rome Continue To Be Mischaracterized As A Barbarian Invasion, Walter Napier

Electronic Theses and Dissertations, 2020-2023

The Fall of Rome (or more specifically the Western Roman Empire) remains a hotly debated subject in the history of Late Antiquity. The Battle of Adrianople can be argued to be the beginning of Rome's end, but the cause of the battle lay more with Rome's imperial mismanagement than any deliberate attempt at war from the barbarians. Rome turned against those who would have defended the empire, and for many centuries had done just that. Despite being forced into an antagonistic relationship with Rome, their reputation as the cause of Rome's calamity has remained to the present day. This thesis …

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Improving Usability Of Genetic Algorithms Through Self Adaptation On Static And Dynamic Environments, Reamonn Norat Jan 2020

Improving Usability Of Genetic Algorithms Through Self Adaptation On Static And Dynamic Environments, Reamonn Norat

Electronic Theses and Dissertations, 2020-2023

We propose a self-adaptive genetic algorithm, called SAGA, for the purposes of improving the usability of genetic algorithms on both static and dynamic problems. Self-adaption can improve usability by automating some of the parameter tuning for the algorithm, a difficult and time-consuming process on canonical genetic algorithms. Reducing or simplifying the need for parameter tuning will help towards making genetic algorithms a more attractive tool for those who are not experts in the field of evolutionary algorithms, allowing more people to take advantage of the problem solving capabilities of a genetic algorithm on real-world problems. We test SAGA and analyze …

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Postcolonial Public Administration: A Critical Discourse Analysis, Esteban Santis Jan 2020

Postcolonial Public Administration: A Critical Discourse Analysis, Esteban Santis

Electronic Theses and Dissertations, 2020-2023

Four years after the passage of the Civil Rights Act of 1964, a group of Public Administration scholars met in New York's Adirondack Mountains to discuss the future of the field. At this gathering, the Minnowbrook I Conference, scholars acknowledged the need for social equity. Today, more than fifty years later, there is still a need for social equity. There is still a need to understand the history and role of oppression within Public Administration. Apropos, in this dissertation, I interrogate oppression, by way of postcolonialism and critical discourse analysis, to learn about the field's darkness and splendor. This project …

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Energy-Efficient Signal Conversion And In-Memory Computing Using Emerging Spin-Based Devices, Soheil Salehi Mobarakeh Jan 2020

Energy-Efficient Signal Conversion And In-Memory Computing Using Emerging Spin-Based Devices, Soheil Salehi Mobarakeh

Electronic Theses and Dissertations, 2020-2023

New approaches are sought to maximize the signal sensing and reconstruction performance of Internet-of-Things (IoT) devices while reducing their dynamic and leakage energy consumption. Recently, Compressive Sensing (CS) has been proposed as a technique aimed at reducing the number of samples taken per frame to decrease energy, storage, and data transmission overheads. CS can be used to sample spectrally-sparse wide-band signals close to the information rate rather than the Nyquist rate, which can alleviate the high cost of hardware performing sampling in low-duty IoT applications. In my dissertation, I am focusing mainly on the adaptive signal acquisition and conversion circuits …

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Culturally Responsive Leadership: Beliefs, Espoused Practices And Supports In High Performing Urban Schools, Jessica Schofield Jan 2020

Culturally Responsive Leadership: Beliefs, Espoused Practices And Supports In High Performing Urban Schools, Jessica Schofield

Electronic Theses and Dissertations, 2020-2023

The racial academic achievement gap, identified as the underachievement of racially, culturally, ethnically, and linguistically diverse (RCELD) students and documented by research, is visible in all education organizations (Griner & Stewart, 2013; National Center for Education Statistics, 2019; O'Connor, Hill, & Robinson, 2009). Since the United States Supreme Court decision of Brown v. Board of Education of Topeka, Kansas, repudiating the concept of separate but equal, laws concerning the need for equal education access have been enacted and educational policies have been created and implemented, but this achievement gap continues to exist (Williams, 2011). Culturally responsive leadership and culturally relevant …

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Wind Turbine Generator Overheating Solution, Gopal Singh Jan 2020

Wind Turbine Generator Overheating Solution, Gopal Singh

Electronic Theses and Dissertations, 2020-2023

An increase in the demand for electrical power and tremendous growth of renewable energy sources has been seen in the last decade, which resulted in designing the wind turbine system components for higher load point performance, resulting in higher annual energy production. Cost optimization, weight reduction, and lower non-conformance cost are some of the expectations that the wind turbine needs to meet in the present stringent market condition. Overheating of the wind turbine system components is one of the primary challenges to overcome when the system operates at a higher load point. The overheating issue of the wind turbine generator …

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Characterization Of Left Ventricular Volumes And Ejection Fraction In Patients With A Left Ventricular Assist Device, Viswajith Siruvallur Vasudevan Jan 2020

Characterization Of Left Ventricular Volumes And Ejection Fraction In Patients With A Left Ventricular Assist Device, Viswajith Siruvallur Vasudevan

Electronic Theses and Dissertations, 2020-2023

In the treatment of heart patients, as a bridge to recovery, the challenge currently in using a continuous-flow left ventricular assist device (LVAD), is to provide a method to monitor the recovery of the heart. This dissertation addresses the hypothesis that continuous monitoring of the ejection fraction of a patient implanted with an LVAD should be to examine the progress of the patient without the need for excessive in vivo measurements. Also, the ejection fraction can be used to provide a control mechanism for the pump depending on the requirements of each patient. In this dissertation, the left ventricle, in …

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Increasing Accuracy Performance Through Optimal Feature Extraction Algorithms, Genevieve Sapijaszko Jan 2020

Increasing Accuracy Performance Through Optimal Feature Extraction Algorithms, Genevieve Sapijaszko

Electronic Theses and Dissertations, 2020-2023

This research developed models and techniques to improve the three key modules of popular recognition systems: preprocessing, feature extraction, and classification. Improvements were made in four key areas: processing speed, algorithm complexity, storage space, and accuracy. The focus was on the application areas of the face, traffic sign, and speaker recognition. In the preprocessing module of facial and traffic sign recognition, improvements were made through the utilization of grayscaling and anisotropic diffusion. In the feature extraction module, improvements were made in two different ways; first, through the use of mixed transforms and second through a convolutional neural network (CNN) that …

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Mfpa: Mixed-Signal Field Programmable Array For Energy-Aware Compressive Signal Processing, Adrian Tatulian Jan 2020

Mfpa: Mixed-Signal Field Programmable Array For Energy-Aware Compressive Signal Processing, Adrian Tatulian

Electronic Theses and Dissertations, 2020-2023

Compressive Sensing (CS) is a signal processing technique which reduces the number of samples taken per frame to decrease energy, storage, and data transmission overheads, as well as reducing time taken for data acquisition in time-critical applications. The tradeoff in such an approach is increased complexity of signal reconstruction. While several algorithms have been developed for CS signal reconstruction, hardware implementation of these algorithms is still an area of active research. Prior work has sought to utilize parallelism available in reconstruction algorithms to minimize hardware overheads; however, such approaches are limited by the underlying limitations in CMOS technology. Herein, the …

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A Legacy Of Community And Mourning: Aids & Hiv In Central Florida, 1983-1993, Andrew Weeks Jan 2020

A Legacy Of Community And Mourning: Aids & Hiv In Central Florida, 1983-1993, Andrew Weeks

Electronic Theses and Dissertations, 2020-2023

Given the primacy of Florida, and in particular Orlando, as an urban center with an above average rate of AIDS and HIV, this study examines how the outbreak of a deadly disease can affect a community. Complicating the response to this scourge, those who were most at-risk were marginalized groups such as those in the LGBTQ community, drug users, and often people of color. As a result, those who occupied positions of political power felt little incentive to curb the epidemic and mocked it by deeming it "the gay disease." As a result of neglect and the lack of investment …

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Party For One: A Monologue Of The Importance Of Oneself Through Book Arts, Jacob Zhefu Wan Jan 2020

Party For One: A Monologue Of The Importance Of Oneself Through Book Arts, Jacob Zhefu Wan

Electronic Theses and Dissertations, 2020-2023

This thesis explores the importance of oneself through sexuality, context, and introspection in the art of book arts. I work with memories, imagination, and consciousness in the form of book arts to express the importance of the self from my personal experience. Through the use of colors, materials, spatial compositions, and other visual components to manifest the content of my art, I want to illuminate the awareness of otherness including gender issues and an individual's vulnerability. Playing with the texts of Chinese and English, I intend to create narratives with languages, images, and other mixed media. In addition to crafting …

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An Analysis Of Teacher Decision-Making In Grading 10th Grade Student Writing In English Language Arts, Guy Swenson Jan 2020

An Analysis Of Teacher Decision-Making In Grading 10th Grade Student Writing In English Language Arts, Guy Swenson

Electronic Theses and Dissertations, 2020-2023

This qualitative study was conducted to investigate teacher decision-making while grading samples of 10th grade student writing in English language arts. Extensive research spanning 100 years has shown that inter-rater agreement of student work is weak at best (Ashbaugh, 1921; Brimi, 2011; Starch & Elliot, 1912). A cognitive laboratory interview method was chosen to focus on real-time teacher decision-making due to a discrepancy between teacher beliefs and teacher practices (Phipps & Borg, 2009). Qualitative data were gathered from 21 cognitive laboratory interviews in which the participants graded two samples of student writing while verbalizing their thoughts. The grading data revealed …

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Explore And Design Novel Structures For More Efficient And Better Deep Convolutional Neural Networks, Min Wang Jan 2020

Explore And Design Novel Structures For More Efficient And Better Deep Convolutional Neural Networks, Min Wang

Electronic Theses and Dissertations, 2020-2023

Deep Convolutional Neural Networks have achieved remarkable performance on visual recognition problems, and have been extensively adopted in real-world applications, such as Apple's Face ID security system, autonomous driving cars, and automatic image tagging in online album services. One major concern in the development of CNNs is that their computational complexity grows along with the increase in their accuracy. Therefore, there is a continuous demand to find the right balance between accuracy and complexity in the design of CNN models. This dissertation focuses on designing various novel structures to enhance the performance of CNNs and their efficiency. Our efforts fall …

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A Corridor Level Gis-Based Decision Support Model To Evaluate Truck Diversion Strategies, Samar Younes Jan 2020

A Corridor Level Gis-Based Decision Support Model To Evaluate Truck Diversion Strategies, Samar Younes

Electronic Theses and Dissertations, 2020-2023

Increased urbanization, population growth, and economic development within the U.S. have led to an increased demand for freight travel to meet the needs of individuals and businesses. Consequently, freight transportation has grown significantly over time and has expanded beyond the capacity of infrastructure, which has caused new challenges in many regions. To maintain quality of life and enhance public safety, more effort must be dedicated to investigating and planning in the area of traffic management and to assessing the impact of trucks on highway systems. Traffic diversion is an effective strategy to reduce the impact of incident-induced congestion, but alternative …

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Transient Mid-Ir Nonlinear Refraction In Air And Nonlinear Optical Properties Of Organometallic Complexes, Salimeh Tofighi Jan 2020

Transient Mid-Ir Nonlinear Refraction In Air And Nonlinear Optical Properties Of Organometallic Complexes, Salimeh Tofighi

Electronic Theses and Dissertations, 2020-2023

This dissertation explores two main topics: Transient nonlinear refraction of air in Mid-IR spectral range and nonlinear optical properties of organometallic complexes. For seeing a vibrational and rotational Raman response the molecule should be Raman active. The first requirement for being a Raman active molecule is that the polarizability of molecule must be anisotropic. Linear symmetric molecules do have rotational Raman spectra. Not all the vibrational mode can be excited by a femtosecond pulse. The pulsewidth of our excitation beam should be less than the half of the vibration period. In this dissertation my excitation pulsewidth is not short enough …

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Paleoethnobotanical Analysis Of Starch Grains And Phytoliths From Pre-Columbian Ceramic Residues In The Bolivian Amazon, Danielle Young Jan 2020

Paleoethnobotanical Analysis Of Starch Grains And Phytoliths From Pre-Columbian Ceramic Residues In The Bolivian Amazon, Danielle Young

Electronic Theses and Dissertations, 2020-2023

The Llanos de Mojos of the southwestern Amazon region of Bolivia once supported large Pre-Columbian indigenous populations who were regarded as skilled farmers, and whose agricultural pursuits are still documented on the landscape through tens of thousands of raised fields. Nevertheless, the plants that were cultivated on these fields that contributed to a large part of the local cuisine are not well understood. Microbotanical analyses using starch grains and phytoliths of food residues were conducted on 55 archaeological ceramic fragments from four forest islands in Mojos where people resided recurrently from cal BCE 1200 to cal CE ~1430. The results …

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Heat Transfer And Correlations Of Jet Array Impingement With Flat And Pimple-Dimpled Plate, Husam Nizar Ahmad Zawati Jan 2020

Heat Transfer And Correlations Of Jet Array Impingement With Flat And Pimple-Dimpled Plate, Husam Nizar Ahmad Zawati

Electronic Theses and Dissertations, 2020-2023

This study compares and analyses the heat transfer between a novel jet array impingement configuration (designated as NPR) and a baseline jet orifice plate (flat) in a maximum crossflow scheme. Both jet plates feature inline arrays of 20 x 26 circular air jets that orthogonally impinge on a flat target surface consisting of 20 segments, parallel to the jet plates. The NPR plate consists of staggered semi-spherical pimples (protrusions) and dimples (imprints) with a jet-to-pimple diameter ratio (Dj,p/Dp) of 0.07 and jet length-to-pimple diameter ratio (L/Dj,p) of ~ 1 with a protrusion ratio (tp/Dj,p) of 2.78. The dimples (imprints) have …

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Transforming English As A Second Language Story Readers Into Storytellers: Examining Learners' Experiences In A Video Book Trailer Project, Shizhong Zhang Jan 2020

Transforming English As A Second Language Story Readers Into Storytellers: Examining Learners' Experiences In A Video Book Trailer Project, Shizhong Zhang

Electronic Theses and Dissertations, 2020-2023

Reading is a challenging task for English as a Second Language (ESL) students (Pang, 2008; Nassaji, 2011). Instructors and researchers have explored various ways to promote ESL students' reading development. Since research on story-based pedagogy has shown benefits in the area of language development, stories can be used to promote ESL reading development. Furthermore, research on Digital Booktalk shows that when students engaged in after-reading video production activities they found a new purpose in reading (Gunter & Kenny, 2012). Additionally, digital storytelling (DST) research has revealed that DST can foster learner motivation and autonomy (Hafner & Miller, 2011; Kim, 2014). …

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Differential Recurrent Neural Networks For Human Activity Recognition, Naifan Zhuang Jan 2020

Differential Recurrent Neural Networks For Human Activity Recognition, Naifan Zhuang

Electronic Theses and Dissertations, 2020-2023

Human activity recognition has been an active research area in recent years. The difficulty of this problem lies in the complex dynamical motion patterns embedded through the sequential frames. The Long Short-Term Memory (LSTM) recurrent neural network is capable of processing complex sequential information since it utilizes special gating schemes for learning representations from long input sequences. It has the potential to model various time-series data, where the current hidden state has to be considered in the context of the past hidden states. Unfortunately, the conventional LSTMs do not consider the impact of spatio-temporal dynamics corresponding to the given salient …

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