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Graduate Theses and Dissertations

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Full-Text Articles in Engineering

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

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 ...


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

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 ...


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

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 ...


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

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 ...


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

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 ...


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

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 ...


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

Morphometry And Density Analysis Of The Fifth Metacarpal, Amrita Unnikumaran

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

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 ...


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

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 ...


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

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 ...


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

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 ...


Thermal Response In A Field Oriented Controlled Three-Phase Induction Motor, Niyem Mawenbe Bawana Jul 2019

Thermal Response In A Field Oriented Controlled Three-Phase Induction Motor, Niyem Mawenbe Bawana

Graduate Theses and Dissertations

The research conducted at the department of Electrical Engineering of the University of South Florida campus in Tampa only covers the electrical aspect of electric drives. However, the performance of electric machinery is significantly impacted by temperature variation. The

literature review shows three main control techniques in use today in electric drives namely, Scalar control, Direct Torque control and Field Oriented control.

This thesis presents a temperature rise of rotor bars, stator winding, stator core and stator frame in a running three phase field-oriented controlled induction machine. A literature search shows that none of research has been carried out to ...


Bamboo As A Sustainable Engineering Material: Mechanical Properties, Safety Factors, And Experimental Testing, Lorena Sánchez Vivas Jul 2019

Bamboo As A Sustainable Engineering Material: Mechanical Properties, Safety Factors, And Experimental Testing, Lorena Sánchez Vivas

Graduate Theses and Dissertations

With exponential global population growth occurring and associated environmentally destructive consumption of natural resources, alternative materials that are fast growing and sustainable are being sought out to satisfy human needs. One material that is fast growing and sustainable that can be used to meet most basic needs of humans (i.e. shelter, food, tools) is the plant bamboo, of the grass family Poaceae. Bamboo was used in the past by native peoples who lived in the environment where bamboo natively grows (all continents except Europe and Antarctica) with proven success for uses such as shelter, piping, tools, wells, food, fencing ...


Effects Of Support Fluid Type On Concrete Integrity And Durability In Drilled Shafts, Sarah J. Mobley Jul 2019

Effects Of Support Fluid Type On Concrete Integrity And Durability In Drilled Shafts, Sarah J. Mobley

Graduate Theses and Dissertations

Until recently, concrete flow in tremie-placed drilled shafts has been mischaracterized as rising uniformly with laitance formation occurring only at the top of the rising concrete in the shaft. In actuality, concrete first fills a portion of the reinforcement cage to a sufficient height to promote radial flow into the cover region. Depending on support fluid type, the radial flow can produce laitance-filled creases/channels projecting the reinforcing cage configuration to the side of shaft surface. The flow pattern (and creases) can affect filter cake thickness, cover quality and propensity for corrosion. This research examines 52 tremie-placed laboratory drilled shaft ...


Study Of Transition Metal Dichalcogenides Via Linear And Non-Linear Spectroscopy, Christopher E. Stevens Jul 2019

Study Of Transition Metal Dichalcogenides Via Linear And Non-Linear Spectroscopy, Christopher E. Stevens

Graduate Theses and Dissertations

Beginning with the discovery of graphene, two-dimensional materials have amassed a strong interest. Like graphene, transition metal dichalcogenides (TMDs) can be coaxed into atomically thin sheets which have some impressive properties. Unlike graphene, TMDs also has a change in their electronic band structure causing an indirect band gap to a direct gap transition in its monolayer form. Additionally, these materials lose their inversion symmetry as a monolayer. These unique properties make TMDs a strong candidate for being used in optoelectronic and valleytronic devices. In order for these devices to be successful, the optical properties of TMDs must be thoroughly understood ...


A Decision-Making Framework For Hybrid Resource Recovery Oriented Wastewater Systems, Nader Rezaei Jun 2019

A Decision-Making Framework For Hybrid Resource Recovery Oriented Wastewater Systems, Nader Rezaei

Graduate Theses and Dissertations

Water shortage, water contamination, and the emerging challenges in sustainable water resources management (e.g., the likely impacts of climate change and population growth) necessitate adopting a reverse logistics approach, which is the process of moving wastewater from its typical final destination back to the water supply chain for reuse purposes. This practice not only reduces the negative impacts of wastewater on the environment, but also provides an alternative to withdrawal from natural water resources, forming a closed-loop water supply chain. However, the design of such a supply chain requires an appropriate sustainability assessment, which simultaneously accounts for economic, environmental ...


The Design Of Passive Networks With Full-Wave Component Models, Eric Valentino Jun 2019

The Design Of Passive Networks With Full-Wave Component Models, Eric Valentino

Graduate Theses and Dissertations

In this thesis, the design of passive networks with the aid of full-wave simulation software and geometry-based models of lumped elements is investigated. This is done by examining the results of a number of simulation examples, as well as measured data from manufactured designs to compare against simulated equivalents. One such example is a chip antenna evaluation board design, in which the PCB, antenna, matching components and connector are all modeled. When measured, the simulation agreed with the board’s best matched frequency of 5.5 GHz to within 20 MHz. In another, a new antenna layout is generated from ...


Encapsulation Of Organic Thermochromic Materials With Silicon Dioxide, Mingyang Huang Jun 2019

Encapsulation Of Organic Thermochromic Materials With Silicon Dioxide, Mingyang Huang

Graduate Theses and Dissertations

Currently, functional materials are attracting considerable attention in the effort to solve some tough challenges the world is faced with. Thermochromic (TC) materials have the potential to make buildings more energy efficient because of their ability to change color (i.e black to white) at specific temperatures. Using this property, TC materials can reflect solar radiation in the summer, to keep a building cool during daytime hours, and absorb solar radiation in the winter to keep the building warm when their color is dark. Very often, to increase their durability, thermochromic materials are encapsulated. In this work, a new process ...


Improving Stability By Enhancing Critical Fault Clearing Time, Ammara M. Ghani Jun 2019

Improving Stability By Enhancing Critical Fault Clearing Time, Ammara M. Ghani

Graduate Theses and Dissertations

The Bulk Electric System (BES) in the United States includes transmission lines of 100kV and above, transformers of 100kV and above on Low Voltage (LV) side and generating units that step up to 100 kV and above. The BES is a power network that connects different states and utility companies via tie lines for exchange of Power.

To maintain the integrity of power systems, it is very important to keep the BES intact and for that the regulatory authority, North American Electric Reliability Corporation (NERC), has developed over 100s of reliability standards and is responsible to enforce them.

During the ...


Effect Of Promoter (Mn) On The Performance Of Sba-15 Supported Iron Catalysts For High Temperature Fischer-Tropsch Synthesis, Sreya Mariya Seby Jun 2019

Effect Of Promoter (Mn) On The Performance Of Sba-15 Supported Iron Catalysts For High Temperature Fischer-Tropsch Synthesis, Sreya Mariya Seby

Graduate Theses and Dissertations

Development of an effective High Temperature Fischer-Tropsch Synthesis (HTFTS) catalyst is of interest in process intensification that combines methane reforming with long chain hydrocarbon production. Literature indicates iron catalysts supported on mesoporous silica performed relatively well in high temperature applications. In this work, we investigated the effect of manganese promoter on iron catalysts for FTS at 430 °C as it was known from previous studies that manganese promotion could enhance the CO conversion with higher hydrocarbon yields. Also, the effect of temperature on FTS activity was evaluated by testing the base and promoted Fe/SBA-15 catalysts for temperature ranging from ...


Morphology And Detection Of Corrosion On Stainless Steel Reinforcement In Concrete, Julio J. Saire Yanez Jun 2019

Morphology And Detection Of Corrosion On Stainless Steel Reinforcement In Concrete, Julio J. Saire Yanez

Graduate Theses and Dissertations

Stainless steel (SS) has emerged as an alternative corrosion-resistant reinforcement in concrete instead of the commonly used carbon steel (CS). The biggest advantage of SS is that it takes more time for corrosion to initiate than for CS. An additional benefit from the use of SS in concrete may be derived from the period after the corrosion started until the concrete structure reaches a limit state. This period is called corrosion propagation stage (CPS) and it has been hardly studied in SS reinforced structures. The duration of this period could be related, among other factors, to the morphology of corrosion ...


Sorption Of Benzene, Tolueneand Ethylbenzeneby Plasticized Pema And Pema/Pmma Sensing Films Using Aquartz Crystal Microbalance (Qcm) At 298.15k, Deekshitha Adapa Jun 2019

Sorption Of Benzene, Tolueneand Ethylbenzeneby Plasticized Pema And Pema/Pmma Sensing Films Using Aquartz Crystal Microbalance (Qcm) At 298.15k, Deekshitha Adapa

Graduate Theses and Dissertations

Detection of volatile organic compounds (VOC’s) in the environment is important for human health and wellness. Long term exposure of certain VOC’s like benzene, toluene, ethylbenzene and xylene (BTEX) has a severe effect on human health. There are techniques such as gas chromatography, photo ionization, and mass spectroscopy that are time consuming, require gas sampling and are ineffective in real time sensing in air. Acoustic wave devices such as surface acoustic wave (SAW) devices can be used for sensing BTEX compounds in both vapor and liquid phase. The quartz crystal microbalance (QCM) is a low-frequency acoustic wave device ...


Prioritizing Rehabilitation Of Sanitary Sewers In Pinellas County, Fl, Jesse T. Hillman Jun 2019

Prioritizing Rehabilitation Of Sanitary Sewers In Pinellas County, Fl, Jesse T. Hillman

Graduate Theses and Dissertations

Following large rain events, extraneous freshwater contributions known as inflow and infiltration (I/I) bypass the storm sewer and enter the sanitary sewer system. In areas with a high water table, like Pinellas County and the surrounding Tampa Bay area, a majority of the wastewater infrastructure is submerged year round exacerbating the rate of groundwater infiltration. This excess flow overloads the existing wastewater infrastructure leading to sanitary sewer overflows (SSOs). These SSOs result in serious problems for municipalities and utilities across the country.

This study was performed in order to assist Pinellas County Utilities in rehabilitating their southern sewer system ...


Cubesat Constellation Design For Intersatellite Linking, Michael T. White Jun 2019

Cubesat Constellation Design For Intersatellite Linking, Michael T. White

Graduate Theses and Dissertations

This thesis investigates the concept of controlling a CubeSat constellation in low-Earth orbit. Low-Earth orbits are considered because the torque used for satellite control is supplied with magnetorquers, and the closer the satellite is to Earth’s magnetic field the more control gain can be supplied. Also, this is the expected orbit altitude of future CubeSat constellations to enable communications.

Controlling a CubeSat relies on attitude determination. This means being able to estimate its attitude relative to a given reference frame. To determine the attitude, we propose to use a star tracker and a Kalman filter. A star tracker scans ...


Design And Testing Of Experimental Langmuir Turbulence Facilities, Zongze Li Jun 2019

Design And Testing Of Experimental Langmuir Turbulence Facilities, Zongze Li

Graduate Theses and Dissertations

Langmuir Circulation is a common phenomenon driven by wind in oceans and lakes and was first studied by Langmuir in 1927. According to various ocean observations, this kind of phenomenon plays an important role in many phenomena such as the aggregation of bubbles, the distribution of plankton as well as the mixing of spilled oil and sediment in the ocean. To study this, an experimental facility has been developed in the lab which creates a small scale version of Langmuir Circulation.

This thesis is about the design and testing of this tank and surrounding aluminum frame, as well as the ...


Authentication And Sql-Injection Prevention Techniques In Web Applications, Cagri Cetin Jun 2019

Authentication And Sql-Injection Prevention Techniques In Web Applications, Cagri Cetin

Graduate Theses and Dissertations

This dissertation addresses the top two “most critical web-application security risks” by combining two high-level contributions.

The first high-level contribution introduces and evaluates collaborative authentication, or coauthentication, a single-factor technique in which multiple registered devices work together to authenticate a user. Coauthentication provides security benefits similar to those of multi-factor techniques, such as mitigating theft of any one authentication secret, without some of the inconveniences of multi-factor techniques, such as having to enter passwords or biometrics. Coauthentication provides additional security benefits, including: preventing phishing, replay, and man-in-the-middle attacks; basing authentications on high-entropy secrets that can be generated and updated automatically ...


Steady State Hydroplaning Risk Analysis And Evaluation Of Unsteady State Effects, Menna Yassin Jun 2019

Steady State Hydroplaning Risk Analysis And Evaluation Of Unsteady State Effects, Menna Yassin

Graduate Theses and Dissertations

Hydroplaning is a major concern on high speed roadways during heavy rainfall events. Hydroplaning tools are widely used by designers to reduce their roadway’s hydroplaning potential, therefore reducing the possibilities of severe crashes. This dissertation presents two methodologies for improving the prediction of hydroplaning potential.

The first phase focused on improving an existing widely used software called PAVDRN. Using multiple datasets from the Florida Department of Transportation, the author filtered the data using specific criteria to leave only truly dynamic hydroplaning crashes. The author then evaluated PAVDRN’s prediction capabilities and assessed its reliability in predicting a hydroplaning crash ...


Characterization Of Geogrid Reinforced Ballast Behavior Through Finite Element Modeling, Bugra Sinmez Jun 2019

Characterization Of Geogrid Reinforced Ballast Behavior Through Finite Element Modeling, Bugra Sinmez

Graduate Theses and Dissertations

Recently, the railway pavement structure system, as an integral part of the transport infrastructure, has been under fast development in some countries such as China, Turkey, and some European Union countries, particularly for the use of high-speed trains. In designing and constructing the railway pavement structure, it is necessary to take into account the infrastructure demand of the High-Speed Railway Lines (HSRL). Compared to traditional railway trains, HSRL can cause more significant problems to the ballast or base layer of commonly used ballasted railway pavements. The deteriorated ballast or base layer may further result in substructure degradation that may cause ...


Security Framework For The Internet Of Things Leveraging Network Telescopes And Machine Learning, Farooq Israr Ahmed Shaikh Apr 2019

Security Framework For The Internet Of Things Leveraging Network Telescopes And Machine Learning, Farooq Israr Ahmed Shaikh

Graduate Theses and Dissertations

The recent advancements in computing and sensor technologies, coupled with improvements in embedded system design methodologies, have resulted in the novel paradigm called the Internet of Things (IoT). IoT is essentially a network of small embedded devices enabled with sensing capabilities that can interact with multiple entities to relay information about their environments. This sensing information can also be stored in the cloud for further analysis, thereby reducing storage requirements on the devices themselves. The above factors, coupled with the ever increasing needs of modern society to stay connected at all times, has resulted in IoT technology penetrating all facets ...


Routing And Designing Networks For Two Transportation Problems, Liu Su Apr 2019

Routing And Designing Networks For Two Transportation Problems, Liu Su

Graduate Theses and Dissertations

Routing and designing are essential for transportation networks. With effective routing and designing policies, transportation networks can work safely and efficiently. There are two transportation problems: hazardous materials (hazmat) transportation and warehouse logistics. This dissertation addresses the routing of networks for both problems. For hazmat transportation, the routing can be regulated via network design. Due to catastrophic consequences of potential accidents in hazmat transportation, a risk-averse approach for routing is necessary. In this dissertation, we consider spectral risk measures, for risk-averse hazmat routing. In addition, we introduce a network design problem to select a set of closed road segments for ...