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Simulating Flood Control In Progress Village, Florida Using Storm Water Management Model (Swmm), Azize Minaz Jun 2022

Simulating Flood Control In Progress Village, Florida Using Storm Water Management Model (Swmm), Azize Minaz

USF Tampa Graduate Theses and Dissertations

Flooding is a natural event caused by heavy rains, melting snow, high tides, and anthropogenic impacts such as channel clogging, improper land use, and deforestation. In this study, the strategies for controlling flooding seek to establish flood prevention systems by implementing grey infrastructure and green infrastructure practices. The main objective of this thesis is to analyze the study area, Progress Village Neighborhood in Delaney Creek Watershed, regarding flood risk and flood mitigation techniques. The analysis was performed using EPA SWMM 5.1 and Arcmap 10.7.1. The study used design storms,10-years 24 hours and 25-years 24 hours, to analyze flood risk in …


Resolution Of Lava Tubes With Ground Penetrating Radar, Sanaz Esmaeili Nov 2021

Resolution Of Lava Tubes With Ground Penetrating Radar, Sanaz Esmaeili

USF Tampa Graduate Theses and Dissertations

Finding habitable places to keep astronauts safe from surface radiation, magnetic storms, and temperature fluctuations will be an important component of future planetary exploration missions. Remote sensing surveys on other planets indicate the presence of lava tubes. Ground Penetrating Radar (GPR) has shown great potential for detection of tunnels in terrestrial environments. In this research, the capabilities of this near surface rapid exploratory tool for detection of lava tubes are investigated. This dissertation describes terrestrial examples of how GPR can be utilized to explore tubes and addresses the capabilities of GPR for resolving tube-related features such as the floor, fractures, …


Factors Controlling Circulation At The Terminus Of A Shallow Seagrass-Dominated Estuary, Fort Desoto Bay, West-Central Florida, Charles Gray Vickery Jun 2021

Factors Controlling Circulation At The Terminus Of A Shallow Seagrass-Dominated Estuary, Fort Desoto Bay, West-Central Florida, Charles Gray Vickery

USF Tampa Graduate Theses and Dissertations

Fort DeSoto Bay is a shallow seagrass-dominated estuary located landward of Mullet Key that is home to the most extensive seagrass beds in all of Tampa Bay. During a period of development in the 1950s and early 1960s, the bay underwent extensive physical modifications, including the construction of earthen causeways and dredged channels, which altered the bathymetry of the seafloor and changed natural circulation patterns. The stagnation of water in the southern bay and increased estuarine residence time led to elevated summer temperatures, reduced dissolved oxygen levels, and die-offs of seagrasses. Two 40-foot circulation bridges were installed on each causeway …


A New Literacy Coach And Two English Language Arts Teachers Learn Together: A Narrative Inquiry, Christiana C. Succar Apr 2019

A New Literacy Coach And Two English Language Arts Teachers Learn Together: A Narrative Inquiry, Christiana C. Succar

USF Tampa Graduate Theses and Dissertations

Literacy coaching is not new to education. Since the 2001 shift in the United States (U.S.) educational policy towards high-quality teacher training, accountability, and student achievement, literacy or reading coach positions have been a core part of the educational institution (U. S. Department of Education, 2003). However, with undefined coaching roles and inadequate coach training early in the initiative, minimal impact on effective teacher development and instructional shifts towards closing the achievement gap occurred (Dole, 2003; International Reading Association, 2004).

In the past ten years, more understanding of literacy coaches’ roles and responsibilities has occurred with the publication of numerous …


Full-Waveform Inversion Of Common-Offset Ground Penetrating Radar (Gpr) Data, Sajad Jazayeri Mar 2019

Full-Waveform Inversion Of Common-Offset Ground Penetrating Radar (Gpr) Data, Sajad Jazayeri

USF Tampa Graduate Theses and Dissertations

Maintenance of aging buried infrastructure and reinforced concrete are critical issues in the United States. Inexpensive non-destructive techniques for mapping and imaging infrastructure and defects are an integral component of maintenance. Ground penetrating radar (GPR) is a widely-used non-destructive tool for locating buried infrastructure and for imaging rebar and other features of interest to civil engineers. Conventional acquisition and interpretation of GPR profiles is based on the arrival times of strong reflected/diffracted returns, and qualitative interpretation of return amplitudes. Features are thereby generally well located, but their material properties are only qualitatively assessed. For example, in the typical imaging of …


Testing And Packaging For Mems Acoustic Emission Sensors, Ting-Hung Liu Jun 2018

Testing And Packaging For Mems Acoustic Emission Sensors, Ting-Hung Liu

USF Tampa Graduate Theses and Dissertations

The goal of this research is to improve the structure and dimension of the MEMS acoustic emission sensor. Acoustic emission sensor (AE sensor) based on the piezoelectric transducer is a well-developed technology in non-destructive testing that is widely used to determine permanent damage such as cracks and corrosions in buildings and structures. The AE sensor can be used to monitor cracks in structures and to check leakage in pressurized systems. The location of cracks in a structure or system leakage causes a high-frequency surface vibration while releasing ultrasonic energy. The frequency of this energy is typically between 30 kHz to …


Development Mems Acoustic Emission Sensors, Adrian Enrique Avila Gomez Nov 2017

Development Mems Acoustic Emission Sensors, Adrian Enrique Avila Gomez

USF Tampa Graduate Theses and Dissertations

The purpose of this research is to develop MEMS based acoustic emission sensors for structural health monitoring. Acoustic emission (AE) is a well-established nondestructive testing technique that is typically used to monitor for fatigue cracks in structures, leaks in pressurized systems, damages in composite materials or impacts. This technology can offer a precise evaluation of structural conditions and allow identification of imminent failures or minor failures that can be addressed by planned maintenances routines. AE causes a burst of ultrasonic energy that is measured as high frequency surface vibrations (30 kHz to 1 MHz) generated by transient elastic waves that …


Multi-Step Tokenization Of Automated Clearing House Payment Transactions, Privin Alexander Nov 2017

Multi-Step Tokenization Of Automated Clearing House Payment Transactions, Privin Alexander

USF Tampa Graduate Theses and Dissertations

Since its beginnings in 1974, the Automated Clearing House (ACH) network has grown into one of the largest, safest, and most efficient payment systems in the world. An ACH transaction is an electronic funds transfer between bank accounts using a batch processing system.

Currently, the ACH Network moves almost $43 trillion and 25 billion electronic financial transactions each year. With the increasing movement toward an electronic, interconnected and mobile infrastructure, it is critical that electronic payments work safely and efficiently for all users. ACH transactions carry sensitive data, such as a consumer's name, account number, tax identification number, account holder …


High Performance Digitally Manufactured Microwave And Millimeter-Wave Circuits And Antennas, Eduardo A. Rojas Jun 2017

High Performance Digitally Manufactured Microwave And Millimeter-Wave Circuits And Antennas, Eduardo A. Rojas

USF Tampa Graduate Theses and Dissertations

The potential of Additive Manufacturing (AM) for microwave and mm-wave applications is increasingly being revealed thanks to recent advancements in research. AM empowers engineers with new capabilities to manufacture complex conformal geometries quicker and at lower costs. It allows, for instance, the embedding of RF front ends into functional structures. In this dissertation, two aspects of AM are explored: (a) The development and characterization of techniques that improve the performance of AM microwave circuits and antennas, and (b) study of complex geometries, such as meshed structures, as an alternative to reduce material usage, cost, and weight of the components.

Micro-dispensing …


Comparing Game Simulation To Concept Models For Student-Centered Learning In Biology, Margaurete Romero Nov 2016

Comparing Game Simulation To Concept Models For Student-Centered Learning In Biology, Margaurete Romero

USF Tampa Graduate Theses and Dissertations

Science education research continues to demonstrate improved learning with active-learning techniques compared to lectures. However, the question of which active-learning methods are the most effective for learning complex scientific principles in various context still remains. Models are commonly used in activities that allow students to simplify complex systems and understand how components interact. I investigated the outcomes for student learning and engagement of two model-based activities - concept models and game simulations. The activities were conducted in an introductory biology course in sixteen discussion sections. Eight sections were assigned to the concept model activity and eight to the simulation activity. …


Enhancement Of Supercapacitor Energy Storage By Leakage Reduction And Electrode Modification, Tete Tevi Mar 2016

Enhancement Of Supercapacitor Energy Storage By Leakage Reduction And Electrode Modification, Tete Tevi

USF Tampa Graduate Theses and Dissertations

Supercapacitors have emerged in recent years as a promising energy storage technology. The main mechanism of energy storage is based on electrostatic separation of charges in a region at the electrode-electrolyte interface called double layer. Various electrode materials including carbon and conducting polymers have been used in supercapacitors. Also, supercapacitors offer high life cycle and high power density among electrochemical energy storage devices. Despite their interesting features, supercapacitors present some disadvantages that limit their competitivity with other storage devices in some applications. One of those drawbacks is high self-discharge or leakage. The leakage occurs when electrons cross the double layer …


Geophysical Evidence For Mid-Crustal Magma Reservoirs In The Lassen Volcanic Region, California, Samantha Catherine Tavarez Nov 2015

Geophysical Evidence For Mid-Crustal Magma Reservoirs In The Lassen Volcanic Region, California, Samantha Catherine Tavarez

USF Tampa Graduate Theses and Dissertations

Regional-scale complete Bouguer gravity anomalies underlying the Lassen and Shasta -Medicine Lake regions in northern California and southern Oregon are associated with subduction of the Gorda plate beneath North America. These generally negative anomalies reflect where underplating has deepened to form the mantle wedge, and where subduction has given rise to a series of Quaternary volcanoes comprising the southernmost end of the Cascade range. Multiple conductive bodies were identified by Park and Ostos (2013) in their magnetotelluric (MT) study of the broader Lassen volcanic region. Their broadband and long period measurements were conducted along a 250 km profile spanning from …


Self-Assembly Kinetics Of Microscale Components: A Parametric Evaluation, Jose Miguel Carballo Jan 2015

Self-Assembly Kinetics Of Microscale Components: A Parametric Evaluation, Jose Miguel Carballo

USF Tampa Graduate Theses and Dissertations

The goal of the present work is to develop, and evaluate a parametric model of a basic microscale Self-Assembly (SA) interaction that provides scaling predictions of process rates as a function of key process variables. At the microscale, assembly by “grasp and release” is generally challenging. Recent research efforts have proposed adapting nanoscale self-assembly (SA) processes to the microscale. SA offers the potential for reduced equipment cost and increased throughput by harnessing attractive forces (most commonly, capillary) to spontaneously assemble components. However, there are challenges for implementing microscale SA as a commercial process. The existing lack of design tools prevents …


Forecasting Corrosion Of Steel In Concrete Introducing Chloride Threshold Dependence On Steel Potential, Andrea Nathalie Sanchez Jul 2014

Forecasting Corrosion Of Steel In Concrete Introducing Chloride Threshold Dependence On Steel Potential, Andrea Nathalie Sanchez

USF Tampa Graduate Theses and Dissertations

Corrosion initiates in reinforced concrete structures exposed to marine environments when the chloride ion concentration at the surface of an embedded steel reinforcing bar exceeds the chloride corrosion threshold (CT) value. The value of CT is generally assumed to have a conservative fixed value ranging from 0.2% to - 0.5 % of chloride ions by weight of cement. However, extensive experimental investigations confirmed that CT is not a fixed value and that the value of CT depends on many variables. Among those, the potential of passive steel embedded in concrete is a key influential factor on the value of CT …


Development Of Catalytic Technology For Producing Sustainable Energy, Syed Ali Z Gardezi Jan 2013

Development Of Catalytic Technology For Producing Sustainable Energy, Syed Ali Z Gardezi

USF Tampa Graduate Theses and Dissertations

This dissertation explores catalyst technology for the production of renewable liquid fuels via thermo-chemical conversion of biomass derived syngas. Fischer-Tropsch synthesis is a process for converting syngas, i.e. a mixture of CO and H2, into energy rich long chain hydrocarbons and oxygenated compounds. This synthesis process involves a number of elementary reactions leading to an array of polymeric products. The economic operation of an FTS process lie in the interplay of both catalyst and reactor design. In relation to catalysis, the nature of chemisorbed species, and the fractional availability of active metal sites determines rate, conversion and yield. Similarly, reactor …


Statistical Topics Applied To Pressure And Temperature Readings In The Gulf Of Mexico, Malena Kathleen Allison Jan 2013

Statistical Topics Applied To Pressure And Temperature Readings In The Gulf Of Mexico, Malena Kathleen Allison

USF Tampa Graduate Theses and Dissertations

The field of statistical research in weather allows for the application of old and new methods, some of which may describe relationships between certain variables better such as temperatures and pressure. The objective of this study was to apply a variety of traditional and novel statistical methods to analyze data from the National Data Buoy Center, which records among other variables barometric pressure, atmospheric temperature, water temperature and dew point temperature. The analysis included attempts to better describe and model the data as well as to make estimations for certain variables. The following statistical methods were utilized: linear regression, non-response …


Investigation Of Mercury Use, Release, Deposition, And Exposures In The Tampa Bay Area, Ryan Algernon Michael Jan 2013

Investigation Of Mercury Use, Release, Deposition, And Exposures In The Tampa Bay Area, Ryan Algernon Michael

USF Tampa Graduate Theses and Dissertations

I investigate the links between mercury use, release, deposition, and population exposure in Tampa Bay, with the focus of identifying levers for reducing population mercury exposures. To achieve this, I investigated the trends in mercury use and release by products and processes in the Tampa Bay area using a Material Flow Analysis. Analysis of USEPA National Emissions Inventory data over time (1999 - 2008) identified relevant air source emission categories, and explored and compared state and regional trends in mercury emissions. To understand source contributions to wet deposited mercury in the Tampa Bay area, I analyzed trends in mercury deposition …


Effect Of Localized Corrosion Of Steel On Chloride-Induced Concrete Cover Cracking In Reinforced Concrete Structures, Ezeddin Rafaa Busba Jan 2013

Effect Of Localized Corrosion Of Steel On Chloride-Induced Concrete Cover Cracking In Reinforced Concrete Structures, Ezeddin Rafaa Busba

USF Tampa Graduate Theses and Dissertations

Abstract: Concrete cover cracking due to reinforcement corrosion is widely accepted as a limit-state indicator in defining the end of functional service life for existing reinforced concrete (RC) structures undergoing corrosion. Many of the currently available durability prediction models are incapable of providing realistic estimates of remaining service lives of RC structures beyond the corrosion initiation point. Therefore, the need to incorporate the length of the corrosion propagation stage in a comprehensive durability prediction approach has recently received much research attention. Previous research focus however was mostly limited to the case of uniformly corroding reinforcement with only few studies addressing …


Tracking Atlantic Hurricanes Using Statistical Methods, Elizabeth Caitlin Miller Jan 2013

Tracking Atlantic Hurricanes Using Statistical Methods, Elizabeth Caitlin Miller

USF Tampa Graduate Theses and Dissertations

Creating an accurate hurricane location forecasting model is of the utmost importance because of the safety measures that need to occur in the days and hours leading up to a storm's landfall. Hurricanes can be incredibly deadly and costly, but if people are given adequate warning, many lives can be spared. This thesis seeks to develop an accurate model for predicting storm location based on previous location, previous wind speed, and previous pressure. The models are developed using hurricane data from 1980-2009.


Packet Coalescing And Server Substitution For Energy-Proportional Operation Of Network Links And Data Servers, Mehrgan Mostowfi Jan 2013

Packet Coalescing And Server Substitution For Energy-Proportional Operation Of Network Links And Data Servers, Mehrgan Mostowfi

USF Tampa Graduate Theses and Dissertations

Electricity generation for Information and Communications Technology (ICT) contributes over 2% of the human-generated CO2 to the atmosphere. Energy costs are rapidly becoming the major operational expense for ICT and may soon dwarf capital expenses as software and hardware continue to drop in price. In this dissertation, three new approaches to achieving energy-proportional operation of network links and data servers are explored.

Ethernet is the dominant wireline communications technology for Internet connectivity. IEEE 802.3az Energy Efficient Ethernet (EEE) describes a Low Power Idle (LPI) mechanism for allowing Ethernet links to sleep. A method of coalescing packets to consolidate link idle …


Optimization In Non-Parametric Survival Analysis And Climate Change Modeling, Iuliana Teodorescu Jan 2013

Optimization In Non-Parametric Survival Analysis And Climate Change Modeling, Iuliana Teodorescu

USF Tampa Graduate Theses and Dissertations

Many of the open problems of current interest in probability and statistics involve complicated data

sets that do not satisfy the strong assumptions of being independent and identically distributed. Often,

the samples are known only empirically, and making assumptions about underlying parametric

distributions is not warranted by the insufficient information available. Under such circumstances,

the usual Fisher or parametric Bayes approaches cannot be used to model the data or make predictions.

However, this situation is quite often encountered in some of the main challenges facing statistical,

data-driven studies of climate change, clinical studies, or financial markets, to name a few. …


Effect Of Cement Chemistry And Properties On Activation Energy, Andre J. Bien-Aime Jan 2013

Effect Of Cement Chemistry And Properties On Activation Energy, Andre J. Bien-Aime

USF Tampa Graduate Theses and Dissertations

The objective of this work is to examine the effect of cement chemistry and physical properties on activation energy. Research efforts indicated that time dependent concrete properties such as strength, heat evolution, and thermal cracking are predictable through the concept of activation energy. Equivalent age concept, which uses the activation energy is key to such predictions. Furthermore, research has shown that Portland cement concrete properties are affected by particles size distribution, Blaine fineness, mineralogy and chemical composition. In this study, four Portland cements were used to evaluate different methods of activation energy determination based on strength and heat of hydration …


Design Of Contact Line Friction Measurement Machine Apparatus, Seyed Kamran Najafi Jan 2012

Design Of Contact Line Friction Measurement Machine Apparatus, Seyed Kamran Najafi

USF Tampa Graduate Theses and Dissertations

The purpose of this project is to design and manufacture a high precision machine to directly measure the surface force of fluids. Knowing how to move droplets easier with less resistance can increase the potential of a wide range of applications and improve the performance of things such as self-assembly applications. This machine has the ability to measure forces of up to 100 N with a MEMS based sensor. The motion system on this machine moves a substrate underneath of a droplet for 100 mm and applies dragging force to the sensor. It moves with a controlled speed with high …


Use Of Innovative Computer Technology And Optical Texture Properties In The Analysis Of Pavement Digital Images, Saumya Priyadari Amarasiri Jan 2011

Use Of Innovative Computer Technology And Optical Texture Properties In The Analysis Of Pavement Digital Images, Saumya Priyadari Amarasiri

USF Tampa Graduate Theses and Dissertations

Digital image based automated pavement crack detection and classification technology has seen vast improvements in the recent years. In spite of these developments, although pavement crack lengths and widths can be evaluated using state-of-the-art software with a reasonable accuracy, no reported evidence is found in extending this technology to evaluate crack depths. Hence a preliminary study was carried out to model the digital image formation of cracked concrete pavements based on the Bidirectional Reflection Distribution Function. It was revealed that a definitive theoretical relationship exists among the crack widths and depths and the maximum pixel intensity contrasts in the images …


Mutual Elements And Substrate Effect Analysis On Patch Antenna Arrays, Matthew J. Wallace Oct 2010

Mutual Elements And Substrate Effect Analysis On Patch Antenna Arrays, Matthew J. Wallace

USF Tampa Graduate Theses and Dissertations

There have been many different technology advancements with the invention of solid state electronics, leading to the digital era which has changed the way users employ electronic circuits. Antennas are no different; however, they are still analog devices. With the advancements in technology, antennas are being fabricated on much higher frequencies and with greater bandwidths, all while trying to keep size and weight to a minimum. Centimeter and millimeter wave technologies have evolved for many different radio frequency (RF) applications. Microstrip patch antennas have been developed, as wire and tubular antenna elements are difficult to fabricate with the tolerances required …


Diffuse Degassing And The Hydrothermal System At Masaya Volcano, Nicaragua, Sophie C. P Pearson Apr 2010

Diffuse Degassing And The Hydrothermal System At Masaya Volcano, Nicaragua, Sophie C. P Pearson

USF Tampa Graduate Theses and Dissertations

Hydrothermal systems change in response to volcanic activity, and in turn may be sensitive indicators of volcanic activity. Fumaroles are a surface manifestation of this interaction. We use time series of soil temperature data and numerical models of the hydrothermal system to investigate volcanic, hydrologic and geologic controls on this diffuse degassing.

Soil temperatures were measured in a low-temperature fumarole field located 3.5 km from the summit of Masaya volcano, Nicaragua. They respond rapidly, on a time scale of minutes, to changes in volcanic activity also manifested at the summit vent. The soil temperature response is repetitive and complex, and …


Corrosion Of Epoxy-Coated Reinforcement In Marine Bridges With Locally Deficient Concrete, Kingsley Lau Mar 2010

Corrosion Of Epoxy-Coated Reinforcement In Marine Bridges With Locally Deficient Concrete, Kingsley Lau

USF Tampa Graduate Theses and Dissertations

Epoxy-coated rebar (ECR) has been used in approximately 300 Florida bridges, in an attempt to control corrosion of the substructure in the splash-evaporation zone. Early severe ECR corrosion was observed in the substructure of several Florida ECR bridges (Group 1) where the substructure was built with permeable concrete of high apparent chloride diffusivity DApp. Other ECR bridges built during the same period and having similar DApp were projected to show corrosion damage starting on the following decade. Examination of several of those bridges (Group 2) confirmed that projection. Other recently examined Florida ECR bridges (Groups 3 and …


Work-Family Conflict, Eating Behaviors, And The Role Of Coping, Ashley G. Walvoord Mar 2009

Work-Family Conflict, Eating Behaviors, And The Role Of Coping, Ashley G. Walvoord

USF Tampa Graduate Theses and Dissertations

There were two primary aims of the present study. The first aim was to examine the relationships between work-interference-with-family (WIF) and specific eating behaviors (eating vegetables, fruits, snack foods) reported by employed mothers, as it relates to health criteria such as BMI. Related to this first aim, household coping strategies were proposed as playing a significant role in the relationship between WIF and eating behaviors. The second aim was to investigate the crossover of WIF to specific child eating behaviors via mother feeding practices or mother eating behaviors.

Self-report and other-report survey data were collected from working mothers and their …


Can Using One Trainer Solely To Deliver Prompts And Feedback During Role Plays Increase Correct Performance Of Parenting Skills In A Behavioral Parent Training Program?, Michael M. Cripe Jul 2008

Can Using One Trainer Solely To Deliver Prompts And Feedback During Role Plays Increase Correct Performance Of Parenting Skills In A Behavioral Parent Training Program?, Michael M. Cripe

USF Tampa Graduate Theses and Dissertations

Behavioral Parent Training refers to a broad range of instructional programs that teach parents and other caregivers ways to build and change behavioral repertoires of children. Most, if not all, such programs employ Behavioral Skills Training (modeling, prompting, role-play practice and feedback) to teach parenting skills. However, specific ways to use prompting during role plays have not been described in the behavioral parent training literature. The present study compared two methods of conducting role plays during parent training. A between group, pretest/posttest design was used to evaluate and compare the effect of using one versus two trainers on the role-play …


Electrochemical Behavior Of Aluminized Steel Type 2 In Scale-Forming Waters, Leonardo Caseres Jun 2007

Electrochemical Behavior Of Aluminized Steel Type 2 In Scale-Forming Waters, Leonardo Caseres

USF Tampa Graduate Theses and Dissertations

Aluminized steel Type 2 (AST2), often used for culvert pipes, is subject to corrosion which is the most important durability limitation factor. It was desired to determine if the outer aluminized layer will retain passivity and if protective galvanic action will develop. Thus, corrosion of unblemished and blemished AST2 surfaces was investigated in simulated natural waters.

Experiments with unblemished specimens showed passive corrosion rates (~0.06 µm/yr) in scale-forming, 0.01 M Cl- solutions but sustained corrosion in other less protective media (with rates 3~10 µm/yr). Corrosion was manifested macroscopically by discoloration and few macro pits, but it likely proceeded also microscopically …