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Innovating Green Stormwater Infrastructure For Nutrient Management: Long-Term Field And Modeling Studies Of Conventional And Modified Denitrifying Bioretention Systems, Emma V. Lopez-Ponnada Nov 2019

Innovating Green Stormwater Infrastructure For Nutrient Management: Long-Term Field And Modeling Studies Of Conventional And Modified Denitrifying Bioretention Systems, Emma V. Lopez-Ponnada

USF Tampa Graduate Theses and Dissertations

Urban stormwater and nutrient management are increasingly important topics to address globally, as coastal urbanization increases, disturbing the natural landscape, hydrology, and water quality. Untreated urban stormwater runoff carries pollutants that enter our waterways, such as rivers and marine environments, which serve as drinking water sources, recreational sites, and locations for economic livelihood. One pollutant and nutrient of concern for water quality is reactive nitrogen (N). Since pre-industrial time, reactive nitrogen has doubled from human activity. When found in excess in waterways, nitrogen causes an overabundant growth of algae, which can result in eutrophic and hypoxic conditions, impacting ecosystems, human …


Rescue Of Hearing And Protection Of Auditory Structures From Noise-Induced Hearing Loss, Reza Amanipour Nov 2019

Rescue Of Hearing And Protection Of Auditory Structures From Noise-Induced Hearing Loss, Reza Amanipour

USF Tampa Graduate Theses and Dissertations

Hearing loss due to exposure to high level sound is a major health problem that causes permanent hearing impairment and has a significant impact on job productivity and quality of life. A large population suffers from noise-induced hearing loss (NIHL), a disorder for which there is currently no FDA-approved prevention, treatment or cure. The goal of my dissertation work is to provide insights into the effects of noise trauma on hearing abilities of normal hearing subjects, and determine how a new therapeutic compound (mGlu7 modulator) can protect and/or prevent loss of, or damage to sensory cells and brain neurons, including …


First-Principles Simulations Of Materials Under Extreme Conditions, Kien Nguyen Cong Nov 2019

First-Principles Simulations Of Materials Under Extreme Conditions, Kien Nguyen Cong

USF Tampa Graduate Theses and Dissertations

The investigation of materials at extreme conditions of high pressure and temperature (high-PT), has been one of the greatest scientific endeavors in condensed mater physics, chemistry, astronomy, planetary, and material sciences. Being subjected to high-PT conditions, materials exhibit dramatic changes in both atomic and electronic structure resulting in an emergence of exceptionally interesting phenomena including structural and electronic phase transitions, chemical reactions, and formation of novel compounds with never-previously observed physical and chemical properties. Although new exciting experimental developments in static and dynamic compression combined with new diagnostics/characterization methods allow to uncover new processes and phenomena at high P-T conditions, …


Trajectory Based Traffic Analysis And Control Utilizing Connected Autonomous Vehicles, Yu Wang Nov 2019

Trajectory Based Traffic Analysis And Control Utilizing Connected Autonomous Vehicles, Yu Wang

USF Tampa Graduate Theses and Dissertations

Recent scholars have developed a number of stochastic car-following models that have successfully captured driver behavior uncertainties and reproduced stochastic traffic oscillation propagation. While elegant frequency domain analytical methods are available for stability analysis of classic deterministic linear car-following models, there lacks an analytical method for quantifying the stability performance of their peer stochastic models and theoretically proving oscillation features observed in the real world. To fill this methodological gap, this study proposes a novel analytical method that measures traffic oscillation magnitudes and reveals oscillation characteristics of stochastic linear car-following models. We investigate a general class of stochastic linear car-following …


High Ammonia Strength Wastewater Treatment Using Algae, Bacteria And Ion Exchange, Nadezhda Zalivina Nov 2019

High Ammonia Strength Wastewater Treatment Using Algae, Bacteria And Ion Exchange, Nadezhda Zalivina

USF Tampa Graduate Theses and Dissertations

Nitrogen pollution has been considered one of the major problems of the 21st century. Discharge of nitrogen from improperly treated wastewaters into surface water bodies causes eutrophication and hypoxia, which results in significant environmental, public health and economic damages. In addition to the incoming flow, wastewater treatment plants generate internal highly concentrated ammonium streams, such as anaerobic digestion sidestream. As a current practice, sidestream without prior treatment is returned to the head of the plant, which increases the total incoming nitrogen load by 20-30% and often exceeds the treatment capacity. The most commonly used conventional biological nitrogen removal processes are …


Dynamic Prediction Of Runway Configuration And Airport Acceptance Rate, Yuan Wang Nov 2019

Dynamic Prediction Of Runway Configuration And Airport Acceptance Rate, Yuan Wang

USF Tampa Graduate Theses and Dissertations

Automated prediction of runway configuration and airport capacity is critical for the future generation of air traffic management. In the future aviation industry, multi-sources weather forecast information will be available for air traffic decision-making units; how to use these data efficiently is key for overall efficiency of air traffic management. Currently, air traffic management personnel lack tools to assist them to translate weather forecast data into real-time airport capacity. Runway configurations and AARs of airports in a multi-airport system are determined by different air traffic controller personnel. The lack of synchronization may lead to the loss of efficiency of the …


Enhancing Concrete Pavement Service Life Using Multiple Strategies To Reduce Cracking Potential, Dhanushika Mapa Mudiyanselage Nov 2019

Enhancing Concrete Pavement Service Life Using Multiple Strategies To Reduce Cracking Potential, Dhanushika Mapa Mudiyanselage

USF Tampa Graduate Theses and Dissertations

Over the past years, prevention of cracking in concrete structures, especially at early age, has been a challenge facing transportation agencies. During early age, restraint of thermal and moisture related volume changes causes cracking in concrete. This research focuses on evaluating the effectiveness of different cracking mitigation strategies that can be implemented, in different concrete elements, to reduce early-age cracking incidents and therefore enhance concrete service life. To this end, a battery of field and laboratory testing were conducted, and finite element analysis was performed to better understand the mechanisms of primary significance on minimizing cracking risks commonly associated with …


Cactus-Based Mucilage As A Natural Dispersant For Crude Oil Spills, Fei Guo Nov 2019

Cactus-Based Mucilage As A Natural Dispersant For Crude Oil Spills, Fei Guo

USF Tampa Graduate Theses and Dissertations

Oil spills are a critical threat to the marine environment, and the spilled oil as a source of pollution can have long-term adverse effects on the marine ecosystem. Traditional mechanical clean-up operations have apparent advantages for dealing with small and medium-scale oil spills. For large-scale oil spills, dispersants are a practical and minimally influential approach to the environment. As the dispersant components are iteratively updated, dispersants become more efficient and safer. However, the toxicity of the dispersants remains a significant impediment to their application. An efficient and non-toxic dispersant is increasingly becoming a requirement.

The cactus mucilage extracts studied in …


Algorithms For Multi-Objective Mixed Integer Programming Problems, Alvaro Miguel Sierra Altamiranda Nov 2019

Algorithms For Multi-Objective Mixed Integer Programming Problems, Alvaro Miguel Sierra Altamiranda

USF Tampa Graduate Theses and Dissertations

This thesis presents a total of 3 groups of contributions related to multi-objective optimization. The first group includes the development of a new algorithm and an open-source user-friendly package for optimization over the efficient set for bi-objective mixed integer linear programs. The second group includes an application of a special case of optimization over the efficient on conservation planning problems modeled with modern portfolio theory. Finally, the third group presents a machine learning framework to enhance criterion space search algorithms for multi-objective binary linear programming.

In the first group of contributions, this thesis presents the first (criterion space search) algorithm …


Phasor Measurement Unit Data-Based Steady State And Dynamic Model Estimation, Anas Almunif Nov 2019

Phasor Measurement Unit Data-Based Steady State And Dynamic Model Estimation, Anas Almunif

USF Tampa Graduate Theses and Dissertations

Phasor measurement units (PMUs) have been put into power grid for real-time monitoring. This research investigates the PMU data for steady state estimation and dynamic model estimation. It focuses on three main research areas to enhance the security of the power system monitoring. First, optimal PMU placement (OPP) problem is developed to minimize the number of PMUs required for the system to be completely observable using mixed integer linear programming and nonlinear programming. Second, PMU measurements are ranked for oscillation monitoring based on two approaches: oscillation mode observability and Prony analysis. Further, the principles, multi-channel data handling, and noise resilience …


Effects Of Reservoir Conditions And Trace Co-Contaminant Gases On Geological Carbon Sequestration, Ram Kumar Nov 2019

Effects Of Reservoir Conditions And Trace Co-Contaminant Gases On Geological Carbon Sequestration, Ram Kumar

USF Tampa Graduate Theses and Dissertations

Geological carbon sequestration in a saline formation is a promising technology for large-scale carbon dioxide (CO2) mitigation. Several factors such as temperature, pressure, salinity, hydraulic conductivity, and mineralogy of a formation affect the CO2 sequestration in saline formations. These factors can vary widely depending upon the type of formation or the degree of heterogeneity within a formation. In addition to these properties of the repositories, the CO2-rich flue gas streams captured from point sources often contains small amounts of impurities such as sulfur oxides (SOx) and nitrogen oxides (NOx), which may have serious implications on the chemistry of the repositories …


Sorption Of Benzene, Toluene, Ethylbenzene And Different Ratios Of Mixture Solvent By Plasticized Pema Films Using A Qcm Sensor, Xinpeng Li Nov 2019

Sorption Of Benzene, Toluene, Ethylbenzene And Different Ratios Of Mixture Solvent By Plasticized Pema Films Using A Qcm Sensor, Xinpeng Li

USF Tampa Graduate Theses and Dissertations

VOCs (volatile organic compounds) can cause great harm to human health especially benzene, toluene and ethylbenzene. In this work a Quartz Crystal Microbalance (QCM) sensor with a polymer/plasticizer film was developed to quantify the VOCs both in air and water. QCM is an acoustic wave sensor that can be used well in detecting the aromatic compounds in the film. Because more than one VOC is present in the air, this thesis focuses on finding the sorption of different ratios of VOCs (benzene, toluene, ethylbenzene) using a polymer/plasticizer film in QCM. Poly (ethyl methacrylate) (PEMA) was used as the polymer because …


Extrusion Of Perovskite Oxide/ Silica Composites For Thermochemical Carbon Dioxide Conversion, Qian Li Nov 2019

Extrusion Of Perovskite Oxide/ Silica Composites For Thermochemical Carbon Dioxide Conversion, Qian Li

USF Tampa Graduate Theses and Dissertations

In order to solve the increasing greenhouse effect problem, perovskite-type oxides have been used to convert CO2 to CO in a reverse water-gas shift chemical looping (RWGS-CL) process. Currently, the process is at the micro-reactor scale and used catalyst in powder form. However, formed materials are needed if the scale is to be increased.

Our research focus is on increasing the conversion yield of perovskite oxides with SiO2 support and scaling up the powder form perovskite-type oxides to pellet by extrusion. The binder added during the extrusion process must be removed to avoid affecting the performance of the catalyst and …


Fabrication And Characterization Of Electrical Energy Storage And Harvesting Energy Devices Using Gel Electrolytes, Belqasem Aljafari Nov 2019

Fabrication And Characterization Of Electrical Energy Storage And Harvesting Energy Devices Using Gel Electrolytes, Belqasem Aljafari

USF Tampa Graduate Theses and Dissertations

Redox-active materials in the bulk of gel electrolytes are unquestionably holding the primary roles in developing energy harvesting and storage technology. Both technologies are necessary in order to cope with the current challenges of the environmental crises of global warming and finite non-renewable sources while the demand for energy modern societies have been speedily increased. One of the most challenges of making a hybrid device of energy conversion and storage is the cost of the fabrication process. Therefore, gel electrolyte-based materials with redox-active properties can potentially be a promising solution to improve the performance of electrochemical and photoelectrochemical devices for …


Thermo-Oxidative Degradation Of Hdpe Geomembranes: Effect Of Phenolic Antioxidant And Hindered Amine Light Stabilizer Concentrations, Yasin Kocak Oct 2019

Thermo-Oxidative Degradation Of Hdpe Geomembranes: Effect Of Phenolic Antioxidant And Hindered Amine Light Stabilizer Concentrations, Yasin Kocak

USF Tampa Graduate Theses and Dissertations

High density polyethylene (HDPE) geomembrane is most common geomembrane which is mainly used for civil engineering applications. However, HDPE geomembrane loses its properties under oxidative degradation progress. This study aims to assess geomembranes which have different percentage of phenolic antioxidant and hindered amine light stabilizer (HALS) with under the six months of the thermal-oxidative degradation. The interactions between phenolic antioxidant, HALS and carbon black can affect the mechanical, physical and chemical properties. To monitor these properties, Differential Scanning Calorimetry (DSC), Fourier-transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy (SEM/EDX), Melt Index tests, …


Enhancing Secrecy And Capacity Of Wireless Systems Using Directive Communications, Mohammed A. Hafez Oct 2019

Enhancing Secrecy And Capacity Of Wireless Systems Using Directive Communications, Mohammed A. Hafez

USF Tampa Graduate Theses and Dissertations

The emerging advances in wireless communications make it an essential component of our everyday life. Moreover, the current research aims towards involving wireless communications in health monitoring applications, which helps medical personnel to remotely keep track of the development of the condition of their patients. Such information is considered highly sensitive and may cause significant harm if acquired by an adversary. The wireless environment has a broadcast type of nature, where the emitted electromagnetic waves spread all over the surrounding area of the transmitting antenna. This broadcast nature raises a considerable concern about the secrecy of this sensitive information while …


Chemolithotrophic Denitrification Of Nitrate Contaminated Groundwater Using Sulfur-Bearing Minerals, John Sutton Oct 2019

Chemolithotrophic Denitrification Of Nitrate Contaminated Groundwater Using Sulfur-Bearing Minerals, John Sutton

USF Tampa Graduate Theses and Dissertations

Nitrate contamination in groundwater resources poses a serious threat, not only to the health of those who would drink it, but also as a potential nutrient for eutrophication. Current methods of nitrate removal can efficiently remove nitrate below 10 mg/L as nitrogen, but may require resources unavailable to small community water systems (SCWS). Sulfur-oxidizing biological denitrification is a promising alternative that may be more suitable for SCWS. Sulfur-oxidizing denitrification has previously been shown to have a high nitrate removal efficiency; however, it produces water high in sulfate. Utilization of sulfide-bearing minerals, rather than elemental sulfur as an electron donor, may …


Morphometry And Density Analysis Of The Fifth Metacarpal, Amrita Unnikumaran Oct 2019

Morphometry And Density Analysis Of The Fifth Metacarpal, Amrita Unnikumaran

USF Tampa Graduate Theses and Dissertations

The fifth metacarpal bone fracture is a common type of fracture among the young male population. With the increasing demand for early recovery from such fractures with surgical reduction, the medical manufacturers and clinicians are interested in designing a better intramedullary device for fixation. This study is an attempt to investigate the dimensional parameters of the fifth metacarpal bone and its intramedullary canal, using 3D CT scan images of cadaveric hands. The algorithm used for measurement applies principal component analysis on the subject bone, to control the information loss and normalize the spatial position of the subject. This analysis provides …


Impact Of The Number Of Lane-Changing Times On Throughput By Fundamental Diagram Based On Ngsim Data, Gangyan Zhang Oct 2019

Impact Of The Number Of Lane-Changing Times On Throughput By Fundamental Diagram Based On Ngsim Data, Gangyan Zhang

USF Tampa Graduate Theses and Dissertations

In the present report, the characteristics of the fundamental diagram (FD) are exploited to delve into the effect of the number of times of lane changes on traffic throughput. The NGSIM data are classified and screened by splitting the regions of US-101 and I-80; the relevant traffic variables (e.g., traffic flow, density and speed) are calculated. Appropriate statistical approaches are employed to verify the correlation of the impact of lane changes on different traffic variables. Lane changes could affect traffic throughput in light congestion instead of in heavy congestion. The causes of the effects of lane changes on throughput are …


Modeling Of Buildings With Electrochromic Windows And Thermochromic Roofs, Hua-Ting Kao Oct 2019

Modeling Of Buildings With Electrochromic Windows And Thermochromic Roofs, Hua-Ting Kao

USF Tampa Graduate Theses and Dissertations

Air conditioning and heating have increased substantially during the past two decades. According to a survey, buildings consume about 73% of the total electricity in the United States, accounting for 41% of all other energy in the world. At the same time, building skin technologies are constantly improving. Electrochromic and thermochromic are two exciting new technologies that can help reduce the energy consumption of a building. The purpose of this work is to increase our understanding of how much the use of electrochromic (EC) and thermochromic (TC) technologies can reduce the energy consumption of residential and commercial buildings in two …


A Gpu-Based Framework For Parallel Spatial Indexing And Query Processing, Zhila Nouri Lewis Oct 2019

A Gpu-Based Framework For Parallel Spatial Indexing And Query Processing, Zhila Nouri Lewis

USF Tampa Graduate Theses and Dissertations

Support for efficient spatial data storage and retrieval have become a vital component in almost all spatial database systems. Previous work has shown the importance of using spatial indexing and parallel computing to speed up such tasks. While GPUs have become a mainstream platform for high-throughput data processing in recent years, exploiting the massively parallel processing power of GPUs is non-trivial. Current approaches that parallelize one query at a time have low work efficiency and cannot make good use of GPU resources. On the other hand, many spatial database applications are busy systems in which a large number of queries …


Device For Imaging Cross-Section Of Post-Tensioned Structural Tendons In The Field, David Dukeman Oct 2019

Device For Imaging Cross-Section Of Post-Tensioned Structural Tendons In The Field, David Dukeman

USF Tampa Graduate Theses and Dissertations

With increasing use of grouted post-tensioned tendons in structures, there is a critical need for equipment to determine deficient grouting. Inadequate grouting can cause dangerous corrosion of the high-strength post-tensioning steel in the tendons. Evaluation should be non-destructive, and early detection is needed to take timely remedial actions to repair or replace any tendons that are affected before catastrophic failure occurs. In particular, there is need for an imaging method that shows the cross-section of the tendon being tested and flag any deficiencies present relative to the location of the strands in the cross section. The method should be rapid, …


Prioritizing Strategic Cyberspace Lethality, Andrew J. Schoka Oct 2019

Prioritizing Strategic Cyberspace Lethality, Andrew J. Schoka

Military Cyber Affairs

The primary concern of United States national security policy, as detailed in the 2018 National Defense Strategy, has shifted from asymmetrical counter-insurgency operations to countering inter-state strategic competition by rogue regimes and revisionist powers. This doctrinal shift has prompted an increased emphasis on military lethality, particularly in strategic-level cyberspace operations intended to counter open challenges to the global security environment and United States preeminence. Drawing from the theory of constraints in industrial engineering and Bayesian search theory in operations research, this paper identifies the key organizational constraints that hinder the lethality of the Department of Defense’s strategic-level cyberspace operations units …


Cyber Metaphors And Cyber Goals: Lessons From “Flatland”, Pierre Trepagnier Oct 2019

Cyber Metaphors And Cyber Goals: Lessons From “Flatland”, Pierre Trepagnier

Military Cyber Affairs

Reasoning about complex and abstract ideas is greatly influenced by the choice of metaphors through which they are represented. In this paper we consider the framing effect in military doctrine of considering cyberspace as a domain of action, parallel to the traditional domains of land, sea, air, and space. By means of the well-known Victorian science-fiction novella Flatland, we offer a critique of this dominant cyber metaphor. In Flatland, the problems of lower-dimensional beings comprehending additional dimensions are explored at some length. Inspired by Flatland, our suggested alternate metaphor for cyber is an additional (fourth) dimension. We …


Distributed Spatiotemporal Control And Dynamic Information Fusion For Multiagent Systems, Dzung Minh Duc Tran Oct 2019

Distributed Spatiotemporal Control And Dynamic Information Fusion For Multiagent Systems, Dzung Minh Duc Tran

USF Tampa Graduate Theses and Dissertations

The first objective of this dissertation is to develop novel distributed control architectures allowing spatiotemporal control of multiagent systems as applied to formation control. In addition, its second objective is to introduce distributed estimation frameworks for dynamic information fusion for addressing the heterogeneity in sensor networks.

Changing the spatial and temporal properties of agent teams in a distributed manner and in real-time is an open problem in the control system literature as multiagent systems are often required to complete tasks with ever-increasing complexity in adverse conditions and dynamic environments. Motivated by this standpoint, this dissertation aims to address challenges related …


Experimental Results Of A Model Reference Adaptive Control Approach On An Interconnected Uncertain Dynamical System, Kemberly Cespedes Oct 2019

Experimental Results Of A Model Reference Adaptive Control Approach On An Interconnected Uncertain Dynamical System, Kemberly Cespedes

USF Tampa Graduate Theses and Dissertations

The objective of this thesis is to show the experimental validation of recently proposed adaptive control architecture for uncertain dynamical systems. The experimental validation is conducted on a benchmark mechanical system setup composed of two carts, one actuated and one unactuated, physically interconnected through a spring.

Specifically, an approach has been recently proposed to stabilize an overall interconnected system in the presence of unknown physical interconnections as well as system uncertainties in the context of model reference adaptive control. This uncertain dynamical system consists of actuated and unactuated portions physically interconnected to each other. In addition, the previous work enforces …


The Combined Effect Of Heat And Corona Charge On Molecular Delivery To A T-Cell Line In-Vitro, Molly A. Skinner Oct 2019

The Combined Effect Of Heat And Corona Charge On Molecular Delivery To A T-Cell Line In-Vitro, Molly A. Skinner

USF Tampa Graduate Theses and Dissertations

Gene therapy and immunotherapy are new up and coming fields in cancer treatment. In August of 2017, the first gene therapy was FDA approved called CAR-T cell therapy("FDA approval brings first gene therapy to the United States," 2017). This therapy uses the patient’s

own T-cells that are genetically modified to attack the cancerous cells. Currently, it takes 4-6 weeks to genetically modify these T-cells, which can be the difference between life and death for a cancer patient (Cheng, Jun, Jiang, & Xi, 2017). There is evidence that gene electrotransfer can help expedite the genetic modification process by having an easy …


Development And Validation Of Wireless Sensors For Applications To Human Head Angular And Mechanical Motions, Karthick Natesan Oct 2019

Development And Validation Of Wireless Sensors For Applications To Human Head Angular And Mechanical Motions, Karthick Natesan

USF Tampa Graduate Theses and Dissertations

In this project, we programmed a 9 degree of freedom Razor sensor, which incorporates an accelerometer and gyroscope to measure the head linear and angular motions produced by activities of daily living (ADL). The majority of studies concentrate on linear accelerations, so the purpose of this study is to determine the importance of both linear and angular components of acceleration in everyday activities and find interlinked relation between them. The sensor was validated using another calibrated and validated system. The general size and wireless nature make this sensor very suitable for use with human subjects. After obtaining informed consent, we …


Toward Car Free Key West, Mary Bishop Aug 2019

Toward Car Free Key West, Mary Bishop

Journal of Transportation Demand Management Research

This paper explores the transportation problems created by the large volume of tourist arrivals to the island of Key West, Florida. A survey of visitors to the island was conducted to uncover their perspectives related to the barriers and benefits of various transportation modes in hopes to inform City staff on the development of transportation options that will meet the needs and desires of tourists. The results from 398 respondents revealed a variety of trends, including varying travel choices depending on the number of visits, where visitors were from, and arrival types. From these trends, priority groups for behavior change …


Hybrid Fusion Protein For Inhibition Of Multiple Proteases For Chronic Wound Healing, Graham L. Strauss Jul 2019

Hybrid Fusion Protein For Inhibition Of Multiple Proteases For Chronic Wound Healing, Graham L. Strauss

USF Tampa Graduate Theses and Dissertations

Many diseases display a multitude of relevant factors that contribute to the persistence of the disease and difficulty treating it. The multifactorial characteristics of some diseases lead to the requirement of combination of treatments in order to restore health. The latter may necessitate the mixing of treatments, medications, and therapeutics to first halt the disease, then assist the human body in returning itself to a state of normality. For example, chronic wounds exhibit this multifactor characteristic in which there exist many factors that lead to the body’s inability to properly heal in a timely manner. This presents a further threat …