Digital Commons Network^™

Development Of Small-Scale Power Supplies For Wearable Medical Diagnostic Devices, Donny Stiner

USF Tampa Graduate Theses and Dissertations

As devices continue the trend of becoming increasingly smaller in scale to allowfor wearability, the power supply modules driving these technologies will in turn become reduced in size as well. This progression will call for advanced techniques to fabricate power supplies on wearable device platforms which still permit the circuit to operate effectively. One such crucial technique, which is discussed in this thesis, is the implementation of power saving measures to increase battery lifespan on wearable devices.

Equipment found in the medical field today can be quite bulky and requireinconvenient means of transportation and take up an excessive amount of …

Trilateration-Based Localization In Known Environments With Object Detection, Valeria M. Salas Pacheco

USF Tampa Graduate Theses and Dissertations

Many strategies for localization have been proposed, the majority of which rely on distance calculations and estimates. The proposed approach is a method that combines image-based single-camera localization techniques and the principle of trilateration to perform localization in a known indoor environment. By using a camera, the proposed system can detect custom objects using object detection in an indoor environment and calculate an approximation of the camera’s position. To recognize the location, previous information such as the size of the environment and the coordinates and sizes of the objects in the environment are given as input to the system together …

Design Of Acoustic Wave Sensor System For Detection Of Btex In Gas Phase, Veselinka Mitevska

USF Tampa Graduate Theses and Dissertations

Benzene, toluene, ethylbenzene, and xylene are classified as volatile organic compounds (VOC), which if present at higher concentrations can cause acute and/or chronic health effects. To protect people from VOCs, the occupational safety and health agency (OSHA) established short term and eight-hour workday exposure limits. The short time levels of exposure for BTEX materials are 5 ppm, 150 ppm, 125 ppm, and 150 ppm, for benzene, toluene, ethylbenzene, and xylene respectively. The eight-hour workday exposure for these same materials are 1 ppm for benzene, 200 ppm for toluene, 100 ppm for ethylbenzene and 100 ppm for xylene. Although there are …

Minimum Cut-Sets For The Identification Of Critical Water Distribution Network Segments, Xiliang Mao

USF Tampa Graduate Theses and Dissertations

To ensure adequate performance of water distribution networks, utilities must identify critical segments within the network that will adversely affect users when failures occur. Currently, time consuming hydraulic simulations are used for such criticality analyses. A method can be of great benefit for utilities if it can easily evaluate the criticality of water distribution network segments. This research applies topology-based methods for the preliminary screening of critical segments. This study evaluated the connectivity between sources and each demand segment in water distribution networks using minimum cut-sets. Through topological analysis, the minimum cut -set between the source node and each demand …

Multi-Material Hybrid Additive And Subtractive Manufacturing Of Photonic Devices, Roger Brandon Tipton

USF Tampa Graduate Theses and Dissertations

Optoelectronics focuses on the application of electronic devices that utilize forms of electromagnetic radiation including visible light and other wavelengths including ultraviolet and infrared. Optoelectronics typically include devices that emit light and detect light. Devices created using this technology include light-emitting diodes, laser diodes, photoresistors, photodiodes, solar cells, phototransistors, and fiber optics. Fiber optic interconnects are interesting devices in that they are used in conjunction with optoelectronic devices to transmit information between individual optoelectronic components.

Optoelectronics are typically produced by traditional lithography methods including etching, writing, and printing on rigid silicon substrates for fabricating devices. Other techniques like glass or …

Driving Health Care Results With Authenticity, Kindness, And Vulnerability: A New Model Of Authentic Leadership, John D. Couris

USF Tampa Graduate Theses and Dissertations

Current management scholars have defined authentic leadership as consisting of four dimensions: relational transparency, self-awareness, balanced processing, and internalized moral perspective. This research extends the concept of authentic leadership to include kindness and vulnerability. I created two scales to measure kindness and vulnerability within the context of leadership and used them to examine perceptions of authentic leadership and its impact on three organizational outcomes: trust in one’s leader, work engagement, and psychological safety. Using a two-group, pretest-posttest experimental design, 44 Tampa General Hospital managers were either selected to participate in a four-hour authentic leadership training that included instruction on kindness …

Plasma Treatment Of High-Density Polyethylene, Linear Low-Density Polyethylene, And Polyvinyl Chloride Geomembranes By Air And Oxygen, Merve Koca Uyar

USF Tampa Graduate Theses and Dissertations

High-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), and polyvinyl chloride (PVC) geomembranes were treated with air and oxygen plasma. The purpose of air and oxygen plasma treatment of geomembrane surface is to increase the surface wettability of these materials, thereby increasing adhesive properties. Increasing adhesive properties enables a surface to be coated with a desired material with antibacterial, antioxidant, and UV resistant characteristics, without changing bulk material properties. To protect the geomembranes from oxidation degradation, UV degradation and biological degradation, it is important to increase the antibacterial, antioxidant, and UV resistant properties of geomembrane. Before and after the plasma treatments …

Effects Of Nitrate On Arsenic Mobilization During Aquifer Storage And Recovery, Hania Hawasli

USF Tampa Graduate Theses and Dissertations

Aquifer storage and recovery technology is used to sustain water resources and to prevent saltwater intrusion. The injected water can come from various resources, including treated wastewater. In pilot ASR studies in the Tampa Bay region, researchers found high As concentrations in the recovered water from the oxidation of the arsenopyrite that is embedded in the aquifers. The presence of dissolved O2 in the injected water is a major factor in the arsenopyrite oxidation during ASR, however the effects of NO3- on the arsenopyrite has not been studied yet. This is an important knowledge gap because injected water may contain …

An Assessment Of Nutrient Improvement In Surface Water Due To The Conversion Of Onsite Sewage Treatment And Disposal Systems To Sewerage, Jenelle A. Mohammed

USF Tampa Graduate Theses and Dissertations

Florida represents approximately 12% of all onsite sewage treatment and disposal systems (OSTDS) in the United States. Properly designed, constructed and maintained OSTDS are effective eco- friendly alternatives for the treatment of domestic wastewater from households not serviced by public sewer systems. However, conventional OSTDS are not designed to effectively remove nitrogen. If installed and improperly used, they may contribute other pollutants. OSTDS have also been linked to degraded water quality in some regions. However, it has been difficult to quantify OSTDS impacts on water quality because of various confounding factors such as point and non-point sources of nutrient input. …

Multi-Object Localization In Robotic Hand, Tsing Tsow

USF Tampa Graduate Theses and Dissertations

We have developed a machine learning approach to localized objects inside a robotic hand using only images from 2D cameras. Specifically, we used deep learning method (You Only Look Once, YOLO) and Iterative closest Point (ICP) to estimate the 3D coordinates of the objects in a robotic hand. This method will also output the number of objects inside the robotic hand in addition to the coordinates of the objects. We have demonstrated the performance with simulation and obtained typical accuracy within a few pixels (couple mm) and counting accuracy of about 76%. We have also applied it to real images, …

Polyethyleneimine-Based High Yield Fluorescent Soluble Covalent Organic Framework, Haonan Wang

USF Tampa Graduate Theses and Dissertations

In this thesis, we report a novel covalent organic framework (COF) with fluorescence and water-soluble features, F-COF-PT with high gravimetric yield (~ 89%), that was generated by the reactions of branched polyethyleneimine (PEI) and 1,3,6,8-Tetrabromopyrene (TBP). The surface area and pore volume were about up to 63.2 m2/g and 0.41 m3/g. The prepared COFs maintained the TBP fluorescent performance in water solutions at 440-460 nm. Furthermore, Cu(II) ion solution would impact the quenching activity with F-COF-PT3, and NaOH treated F-COF-PT3 has the 5.6 m2/g capacity of uptake CO2. Finally, the zeta potential and particle diameter of original and treated F-COF-PT3s …

Modeling The Ambient Conditions Of A Manufacturing Environment Using Computational Fluid Dynamics (Cfd), Yang Liu

USF Tampa Graduate Theses and Dissertations

As manufacturing equipment evolve to higher speed and require high precision operations, the impact of environmental changes on machine accuracy becomes critical. Due to thermal expansion, the structure of the machine can change when ambient temperature varies. When the airflow in the laboratory changes, this also alters the operator's thermal comfort. Either the change in machine structure or operator comfort can ultimately affect machine accuracy. The manufacturing industry is currently using heating, ventilation, and air-conditioning (HVAC) systems to regulate the temperature of the working environment. However, since conventional HVAC systems determine whether to activate the HVAC system by collecting the …

Material And Topographically Optimized Thermal Dissipation For High-Performance Electronic Devices Utilizing Vapor Chambers, Derek Joseph Daniels

USF Tampa Graduate Theses and Dissertations

Advances in materials science and engineering in the field of thermal transport and dissipation enable the use of higher-performance electronic devices that are smaller and generate more heat. Phase change thermal transport systems such as heat pipes and vapor chambers enable passive dissipation from devices that generate excessive heat without the need for actively pumped cooling systems. Properly designed vapor chamber enabled systems easily exceed the thermal conductivity of manufactured diamond at a small fraction of the cost.[1][2][3] While heat pipe phase change systems are generally one-dimensional with a limited cross section, vapor chambers are generally two-dimensional with a small …

Informing Complexity: The Business Case For Managing Digital Twins Of Complex Process Facilities As A Valuable Asset, William Randell Mcnair

USF Tampa Graduate Theses and Dissertations

The Digital Twins of complex facilities, specifically 3D models created during their design, is a potentially valuable information asset. This three- article dissertation explores the business case for firms in the petrochemical process industry to manage throughout the facility lifecycle. A maturity model is provided to illustrate the stages of digital twin evolution and serves as a tool to help communicate each of the five levels of digital twin maturity achievable in various use cases. An industry analysis reviews existing literature and proposes a model to assess informing or insight value of digital twins from three perspectives. Next, an empirical …

Residential Curbside Recycle Context Analysis, Ntchanang Mpafe

USF Tampa Graduate Theses and Dissertations

Curbside recycling as a preferred mode of residential and municipal sustainability goals seems to have an overwhelming acceptance and adoption in the US. About 69.8 million out of 97.3 million (72%) single-family households in the United States have access to curbside recycling services (State of Curbside Recycling Report, 2020). Collectively, the programs divert about nine million tons of recyclables from landfill disposal each year (Cottom, 2019).

For a design that started in the 1980s in the US, its rapid universal adoption seems to have precluded a concerted effort in examining the coproduced nature (Households: service receptors and Municipalities: service providers) …

Texturing In Bi2Te3 Alloy Thermoelectric Materials: An Applied Physics Investigation, Oluwagbemiga P. Ojo

USF Tampa Graduate Theses and Dissertations

Thermoelectric devices provide the means for direct conversion between heat and electricity. The device conversion efficiency, or performance, is directly related to the thermoelectric figure of merit, ZT, of the working materials. Bismuth telluride alloys are the materials currently in use in most thermoelectric devices for near room temperature solid-state refrigeration and power conversion applications. The vast majority of publications in the literature on thermoelectricity report on investigations towards developing new materials with enhanced thermoelectric properties, however Bi₂Te₃ alloys have been used in thermoelectric devices for decades.

In this thesis, an investigation of crystallographic texturing on large …

Automated Identification Of Stages In Gonotrophic Cycle Of Mosquitoes Using Computer Vision Techniques, Sherzod Kariev

USF Tampa Graduate Theses and Dissertations

In this paper, we design Computer Vision techniques to determine stages in the Gonotrophic cycle of mosquitoes. The dataset for our problem came from 125 adult female mosquitoes - each of which belonged to one of three species - Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi. The mosquitoes were raised in a lab and passed through all fourGonotrophic stages (Un-fed, Fully-fed, Semi-gravid, and Gravid). At each stage, their images were captured on a plain background via a Xiaomi smartphone, resulting in a dataset of 1784 images. The images were then augmented using standard techniques to generate a larger dataset of …

Assessing Morphological Response And Vulnerability Of Barrier Islands To Extreme Storms In Northwest Florida, Jacob Adam

USF Tampa Graduate Theses and Dissertations

Barrier islands shield the mainland coast from the effects of extreme storms such as increased wave energy and storm surge. During these events, however, barrier morphology can be altered by erosive forces. Thus, compromising the protection offered and leading to increased impact on the mainland. The St. Joseph Peninsula, located in the Northwest of the Gulf of Mexico, is one such barrier at threat from storm-induced erosion. Presented here is an assessment of morphology change induced by two major storms to impact the peninsula, Hurricanes Dennis 2005 and Michael 2018. These changes characterize the erosive/depositional patterns that can be expected …

Computer Simulation For Continuous Centrifugation Of High-Density Cell Cultures, Hironori Tomizawa

USF Tampa Graduate Theses and Dissertations

Perfusion bioreactors are used for cell production for cell therapies. The system uses cell separation devices such as centrifuge to facilitate cell growth by separating cells and spent media and allows constant media replacement. However, current cell separation technologies can increase shear stress, are generally not continuous processes, and are not as efficient as desired. These limit the amount of media replaced per unit time. Therefore, there is a need for a new system or a method that operates continuously to minimize cell damage, yield high cell concentration, and exchange media effectively. A set of research questions was formulated: (1) …

Using Hyper-Dimensional Spanning Trees To Improve Structure Preservation During Dimensionality Reduction, Curtis Thomas Davis

USF Tampa Graduate Theses and Dissertations

Understanding relations in hyper-dimensional data is a prevalent problem, which is often approached by using dimensionality reduction. The structure preserved from the original data is often dependent on the type of dimension reduction algorithm used, and it can produce results that vary substantially from one another. Visualizing hyper-dimensional data helps to understand the data, but it presents a problem, as our visualizations rely upon two or three-dimensional displays. Current dimension reduction methods, used to reduce hyper-dimensional data to low-dimensional data, often produce results that fail to preserve the structure as the complexity of the data increases. This reduction in dimension …

Constructing Frameworks For Task-Optimized Visualizations, Ghulam Jilani Abdul Rahim Quadri

USF Tampa Graduate Theses and Dissertations

Visualization is crucial in today’s data-driven world to augment and enhance human understanding and decision-making. Effective visualizations must support accuracy in visual task performance and expressive data communication. Effective visualization design depends on the visual channels used, chart types, or visual tasks. However, design choices and visual judgment are co-related, and effectiveness is not one-dimensional, leading to a significant need to understand the intersection of these factors to create optimized visualizations. Hence, constructing frameworks that consider both design decisions and the task being performed enables optimizing visualization design to maximize efficacy. This dissertation describes experiments, techniques, and user studies to …

Unintended Consequences? Testing The Effects Of Adolescent-Targeted Anti-Vaping Media Upon Adult Smokers, Leslie E. Sawyer

USF Tampa Graduate Theses and Dissertations

A great deal of controversy surrounds e-cigarettes, with some arguing that protection of youth and non-users is paramount and others maintaining that these products are beneficial from a harm reduction perspective for use by adult smokers for switching from combustible cigarettes and for smoking cessation. Opponents of e-cigarettes have allocated tremendous funds toward advertising campaigns aimed at youth deterrence; however, to date, the effects of these ads upon adult smokers have yet to be examined. The current study used a between-subjects experimental design to investigate the effects of an FDA-distributed youth-targeted anti-vaping PSA, “Vaping is an Epidemic,” upon adult smokers …

Dynamical System And Parameter Identification For Power Systems, Abdullah Abdulrahman Alassaf

USF Tampa Graduate Theses and Dissertations

The complexity of dynamical analysis has been growing to suffice the understanding and modeling of dynamical systems. Besides its nonlinearity and high-dimensionality, the dynamics of power systems contain uncertainty that complicates its analysis. Recently, dynamical modeling has been categorized into three types: white-box, black-box, and gray-box. White-box modeling has the accessibility of all system components. Black-box modeling has the observability of the system measurements without knowing the actual system. Gray-box modeling has the observability of the system measurements with the reachability to some of the system components. The scope of this dissertation focuses on black-box and gray-box models to achieve …

Impacts Of Automated Vehicle Technologies On Future Traffic, Xiaowei Shi

USF Tampa Graduate Theses and Dissertations

Recently manufactured commercial vehicles are increasingly equipped with automated driving features. The adaptive cruise control (ACC) system, arguably the most common automated vehicle (AV) driving feature, is available on many new models of commercial vehicles in recent years. The ACC system is composed of a series of onboard sensors (e.g., millimeter-wave radars), computing and control units, which enables the commercial AVs to automatically maintain a safe headway between the subject AV and the lead vehicle by dynamically control the AV speed with real-time sensor information. Note that such commercial AVs are controlled by exact, prescriptive, and fast-responding computer-mechanical dynamic models …

Employees Breaking Bad With Technology: An Exploratory Analysis Of Human Factors That Drive Cyberspace Insider Threats, Marcus L. Green

USF Tampa Graduate Theses and Dissertations

As implementation of computer systems has continued to grow in business contexts, employee-driven cyberspace infractions have also grown in number. Employee cyberspace behaviors have continued to have detrimental effects on company computer systems. Actions that violate company cybersecurity policies can be either malicious or unmalicious. Solutions, by and large, have been electronic and centered on hardware and software. Those proposing solutions have begun to shift their focus to human risk vulnerabilities.

This study was novel in that its focus was identification of individual, cultural, and technological risk factors that drive cyberspace insider threat activities. Identifying factors that reduce insider threat …

Cellular And Molecular Alterations Associated With Ovarian And Renal Cancer Pathophysiology, Ravneet Kaur Chhabra

USF Tampa Graduate Theses and Dissertations

Elucidating molecular alterations underlying tumor development and chemoresistance are critical to expand our understanding of the disease pathophysiology. This dissertation is focused on analyzing the cellular and molecular alterations associated with LPA-induced chemoresistance in clear cell renal cell carcinoma (ccRCC) cells and chronic iron-induced deregulation of miRNA expression in fallopian tube secretory epithelial cells (FTSECs).

Kidney cancer is one of the ten most common cancers worldwide with <15% survival rate at advanced stage (American Cancer Society). ccRCC is the most common type of kidney cancer and is described as a metabolic disease characterized by deregulated lipid metabolism leading to increased intracellular lipid droplets [9, 10]. The current molecular-targeted treatment strategies involve VEGF/VEGFR and mTOR inhibition [9, 12]. However, there are limitations to these approaches leading to the reduced efficacy and/or increased resistance in ccRCC cells [13, 14]. Therefore, it is important to decipher the factors involved in compromising the chemosensitivity in these cells.

Lysophosphatidic acid (LPA), a bioactive phospholipid, was previously reported to increase resistance against Sunitinib (VEGFR/PDGFR inhibitor) in ccRCC cells and to increase migration and invasion in various tumors [15-17]. In Chapter 3 of …

Development Of Carbon And Silicon Carbide Based Microelectrode Implantable Neural Interfaces, Chenyin Feng

USF Tampa Graduate Theses and Dissertations

The use of neural modulation techniques to treat nervous system disorders, as well as neural recording to study brain function, continues to be of intense interest around the world. Due to the need to treat diseases such as Parkinson’s, dementia, depression and return normal function to patients suffering from nervous system damage and trauma, neural implants continue to be developed globally. One of these devices, the microelectrode implantable neural interface (mINI), has been rapidly developed, thanks to advanced semiconductor fabrication processes. However, the long-term reliability of present-day devices has still to be demonstrated and is delaying the application of this …

Social Constructivism In Chemistry Peer Leaders And Organic Chemistry Students, Aaron M. Clark

USF Tampa Graduate Theses and Dissertations

Social constructivist learning is a goal in many STEM programs. The goal of this dissertation is to shed light on what that pedagogy looks like in the context of organic chemistry courses and by peer leaders whose job is to implement this pedagogy with general chemistry and organic chemistry students. Learning is complex; the social constructivist ideas presented in this dissertation, however, are a straightforward means for promoting learning. Qualitative and quantitative methods used to explore social constructivist learning are outlined.

Three investigations were conducted: First, approaches to learning by students completing the first semester of a yearlong organic chemistry …

Human-Centered Cybersecurity Research — Anthropological Findings From Two Longitudinal Studies, Anwesh Tuladhar

USF Tampa Graduate Theses and Dissertations

Cybersecurity is a pressing issue. Researchers have proposed numerous security solutions over the years in order to combat security issues but it is still common to find known, well understood security issues in production environments. In this thesis, I seek to find the underlying reasons to why existing security solutions and best practices are not consistently applied and how to improve the utilization of secure best practices. To this end, I adopt the anthropological research method of long term participant observation and embed myself in real-world settings in order to understand the existence of security issues and the perception of …

Synthesis Of Small Molecules For The Treatment Of Infectious Diseases, Elena Bray

USF Tampa Graduate Theses and Dissertations

Drug discovery’s impact on modern healthcare cannot be measured. In the past year, the world has watched scientists all around the globe work together to help protect the public from the novel coronavirus pandemic. Although sometimes slow and costly, drug discovery is important for advancing modern society. Drug discovery is at the core of treating diseases and in particular, infectious diseases. In the first chapter an overview of drug discovery will be discussed in a brief manner.

The second chapter will introduce infectious diseases. In modern society, the development of small molecule treatments for treating bacteria, viruses, and fungi has …