Engineering Commons^™

Designing Next-Generation Transportation Systems With Emerging Vehicle Technologies, Zhiwei Chen

USF Tampa Graduate Theses and Dissertations

Recent advances in computing and artificial intelligence have enabled the development of various emerging vehicle technologies, e.g., autonomous vehicles (AV) and modular autonomous vehicles (MAV). These technologies bring new scientific and engineering problems challenging transportation researchers and practitioners. This dissertation aims to develop a suite of scalable computational and analytical tools for designing and analyzing next-generation transportation systems with the MAV technologies. Also, we intend to empirically study the system impacts in terms of the quality of service, energy implications, and inequality impacts.

For MAV system design, we develop a methodological framework centering at theoretical properties of the optimal system …

Coral Reef Restoration In The Tropical West Atlantic Amid The Covid-19 Pandemic, Linden Cheek

USF Tampa Graduate Theses and Dissertations

Climate change is increasing threats to coasts, both from storm surge and sea level rise. Healthy coral reefs provide reduction in storm surges, wave energy, coastal flooding and everyday erosion, and are found across a variety of spatial scales. Given the state of coral reefs worldwide, active Coral Reef Restoration (CRR) in emerging as a necessary component of coastal protection. CRR can be classified as a nature-based solutions (NbS) for coastal protection that also provides a multitude of ecosystem-based services to both humans and other life. Nearly all literature on coral restoration efforts assume a steady-state of human-ecological interactions, but …

A Framework For Assessing The Reliability, Availability, Maintainability, And Safety (Rams) Of Decentralized Sanitation, Adefunké Adeosun

USF Tampa Graduate Theses and Dissertations

In established industry sectors, Reliability, Availability, Maintainability, and Safety (RAMS) risk assessments are normally used to compare the risks associated with different technologies on process units. Sanitation solutions are split into traditional wastewater treatment which is centralized treatment and can be classified as an established industry, and decentralized treatment such as pit latrines and septic tank systems which are on much smaller scales. Also they can be classified as non-conventional methods such as reinvented advanced decentralized non-sewered sanitation solution techniques exist mainly in two forms as “Single-User Reinvented Toilet (SURT)” systems or “Multiple-User Reinvented Toilet (MURT)” systems. Advanced decentralized non-sewered …

Strength Restoration Of Corrosion Damaged Piles Repaired With Carbon Fiber Reinforced Polymer Systems, Jethro Clarke

USF Tampa Graduate Theses and Dissertations

Of the 12,741 bridges accounted for by the Florida Department of Transportation (FDOT), approximately 50% were built between the 1950s and 1960s. During this period, bridges were typically constructed in coastal environments using pile bents. Now, the main threat to bridges in these environments is corrosion, which occurs in the splash zones of most bridge piles. These zones contain high concentrations of chlorides, oxygen and moisture, the corner stones of a highly corrosive environment. Corrosion compromises steel reinforcement in these areas leading to cracking, spalling and an inevitable loss of capacity.

In recent years, significant strides have been made in …

An Inferential Study Of The Potential Consumer Value Of Free Charging For Users Of Public Electric Vehicle Charging Infrastructure, Divyamitra Mishra

USF Tampa Graduate Theses and Dissertations

Although there is economic and marketing evidence of consumers assigning additional benefits to free products and bundles, there is limited research into the behavioral consequences of offering public electric vehicle charging for free. Previous exploratory research by Maness and Lin analyzed possible economic and environmental benefits from offering free public charging infrastructure and policy. Their work found that providing free public charging infrastructure could increase plug-in electric vehicle sales and cause decreased reliance on fossil fuels in the personal transportation sector. However, their study assumed the increased value which consumers would place on free charge events. This project proposes to …

Black Lives Matter In Engineering, Too! An Environmental Justice Approach Towards Equitable Decision-Making For Stormwater Management In African American Communities, Maya Elizabeth Carrasquillo

USF Tampa Graduate Theses and Dissertations

The United States and the world have recently been challenged with the disparate effects of COVID-19 and the continual killings of unarmed Black men and women across the nation. A history of anti-black racism has led to systemic structures of inequity that thread throughout institutions and communities across the nation. This environmental engineering research comes at a time when understanding how to effectively engage in, and with Black communities is at the forefront of discourse in academia, utilities and private sector.

In 2018 the Brookings Institute published a report on workforce in the water sector demonstrating the lack of diversity …

Using A Systems Thinking Approach And Health Risk Assessment To Analyze The Food-Energy-Water System Nexus Of Seaweed Farming In Belize, Estenia J. Ortiz Carabantes

USF Tampa Graduate Theses and Dissertations

Certain macroalgae, commonly referred to as seaweed, have traditionally been used as a food source for many coastal communities around the world. In Belize, residents of the Placencia Peninsula cultivate two seaweed types, Eucheuma isiforme and Gracilaria spp. at Little Water Caye located 19 miles offshore. The dried seaweed is sold at the Placencia Producers Cooperative Society Limited (PPCSL) where community members process it into a variety of value-added products such as soaps, cosmetics, hair products, and food additives.

The overall goal of this research was to understand the existing food-energy-water system (FEWS) infrastructure landscape for seaweed production in Placencia, …

Sustainable Nutrient Management Through Technology-Level Evaluation And System-Level Optimization, Xiaofan Xu

USF Tampa Graduate Theses and Dissertations

The need for wastewater and stormwater quality control, especially the control of nutrients, has been recognized due to the widespread problem of water eutrophication. Sustainable nutrient management is essential to reduce nutrient-related impacts and supply the growing nutrient demands.

This research focused on the nutrients (nitrogen and phosphorus) in the urban water environment with nitrogen as the nutrient of interest since nitrogen is the primary nutrient responsible for eutrophication in the coastal areas. It aimed to enhance the sustainability of urban nutrient management through technology-level evaluation and system-level optimization of technology implementation with consideration of life cycle environmental impacts and …

Development Of An Integrated Direct Membrane Filtration (Dmf) And Anaerobic Membrane Bioreactor (Anmbr) System For Dilute Municipal Wastewater Treatment, Ahmet Erkan Uman

USF Tampa Graduate Theses and Dissertations

The total electricity consumption due to municipal wastewater treatment in the US accounts for 1.3% of total demand. Also, a significant portion of biodegradable constituents in wastewater is converted into biomass, which needs further processing. On the one hand, an excessive amount of energy and chemicals are being used to treat wastewater, but on the other hand, resources (such as nitrogen and phosphorus, energy, and water) in wastewater are being discharged or removed rather than recovered. From this perspective, new wastewater treatment technologies are sorely needed to facilitate resource recovery from wastewater for a better, more sustainable future.

Anaerobic membrane …

Socio-Technical Transitions In The Water Sector: Emerging Boundaries For Utility Resilience In Barbados, Wainella N. Isaacs

USF Tampa Graduate Theses and Dissertations

Resilience is gaining popularity in the water sector where it described as contributing to reduced vulnerability to water-related risks and hazards including climate change. Unfortunately, literature in this area, contributed mainly from North America and Europe, is fragmented with a concentration on engineering resilience in water supply infrastructure. The absence of any scholarship on resilience for a small island nation, coupled with the absence of sociological contributors to building resilience in this sector motivated this research.

The goal of this research was to understand and evaluate how resilience is characterized and operationalized in the Barbados water and wastewater infrastructure system, …

Effects Of Physical And Chemical Characteristics Of Slags And Cements On Durability Of Portland Cement-Slag Blended Systems, Farzaneh Nosouhian

USF Tampa Graduate Theses and Dissertations

Ground granulated blast furnace slag (GGBFS) which is a commonly used supplementary cementitious material (SCM) needs to be more investigated for improving durability of concrete elements and service life of concrete structures. This research focuses on the effect of the physical and chemical characteristics of GGBFS and portland cement on durability of portland cement-slag blended systems. The effect of cement replacement level is also investigated using control mixes (no slag) and four different levels of slag content. To this end, eight GGBFS and eight portland cements were selected based on their physical characteristics and chemical composition. Four series of experimental …

The Effects Of Surface-Water Flow On The Quality Of Groundwater And Surface-Water Systems, Quanghee Yi

USF Tampa Graduate Theses and Dissertations

My research has focused on the effects of surface-water flow on the quality of groundwater and surfacewater systems. For the first part of my research (Chapter 2 ), I s tudied the effects of s urface flow system changes in the water-conservation areas and canals in southeast Florida on the quality of groundwater in the surficial aquifer system.

For the second part of my research, by developing analytical models using the superposition method, I investigated the effects of bidirectional surface-water flow on the conservative contaminant concentrations (Chapter 4) and mean residence time (Chapter 5) in streams and rivers as well …

Bio-Electrochemical Denitrification Systems And Applications For Nitrogen Removal In On-Site Wastewater Treatment, Kamal Ziad Taha

USF Tampa Graduate Theses and Dissertations

Denitrification experiments using biological cathodes (biocathodes) were conducted in three separate experiments. The first experiment was to observe whether the rate of denitrification in biocathodes could be increased with added ammonium at mass (mg/L) ratios of 0.100 (2.5/25), 0.05 (1.25/25), 0.0250 (0.625/25), and 0.0125 (0.3125/25) (parts ammonium to nitrate (NH4+-N/ NO3--N). The purpose of the ammonium present was to provide the microorganisms a starting nitrogen source for assimilation to biomass which, in theory, would encourage the removal of nitrate through dissimilatory denitrification. As mixed cultures were used, ratios tested were based on simplifying future operation of scaled-up biocathodes applied to …

Structural And Agricultural Value At Risk In Florida From Flooding During Hurricane Irma, Alexander J. Miller

USF Tampa Graduate Theses and Dissertations

Flooding is the most costly type of natural disaster, as well as the most frequent. To provide risk-based flood insurance, providers such as FEMA must be able to accurately determine an asset’s risk of flooding. Additionally, after a flooding event, providers need to quickly determine the direct damages that occurred to verify insurance claims and provide assistance to the affected communities. Many current approaches to flood risk and flood damage estimation involve the use of data or statistical extrapolation that can add various sources of uncertainty into the final damage estimate. In order to reduce uncertainties in flood risk analyses, …

Water Quality And Sustainability Assessment Of Rural Water Systems In The Comarca Ngäbe-Buglé, Panama, Corbyn Cools

USF Tampa Graduate Theses and Dissertations

Over the last four decades significant progress has been made on providing people access to improved drinking water. The Joint Monitoring Program (JMP) estimates that 6.7 billion people have access to at least basic drinking water services. In spite of this great achievement 785 million people still lack even basic services and eighty percent of which live in rural areas. To further complicate matters, those with access to services experience interruptions or non-functionality for handpumps and piped system long before the intended design life of the system. In the Comarca Ngäbe-Buglé province in Panama there is very little information on …

Development Of An Organic Processor Assembly (Opa) For Sustainable Resource Recovery To Enable Long-Duration, Deep-Space Human Exploration (Loddshe), Talon James Bullard

USF Tampa Graduate Theses and Dissertations

Long-Duration, Deep-Space Human Exploration (LoDDSHE) missions demand robust and reliable technologies to ensure crew health, safety, and mission success. In situ food production will become essential for these missions for crew nutrition, morale, and in the event of delays or failures. At a current estimated cost $10,000/lb, mass and volume limitations will restrict necessary resources. For an anticipated thirty-month mission to Mars, these costs will increase due to more frequent resupply shipments and lengthened transit times, creating additional financial and logistical challenges (Pickett et al., 2019). Increased resource and waste recovery to achieve nearly closed-loop systems will mitigate many of …

Rapid Cross-Section Imaging With Magnetic And Impedance Sensors For Grout Anomaly Detection In External Post-Tensioned Tendons, Hani Freij

USF Tampa Graduate Theses and Dissertations

Post-tensioned (PT) bridges have had severe corrosion issues with tendons that fail suddenly without prior notice. The corrosion of external post-tensioned tendons has been associated with grout deficiencies/anomalies from inadequate grouting. Deficiencies include voids, regions of chalky low strength grout, and regions where excessive water content or even free water is present. In those zones mechanical bonding of strand to the grout is degraded and, of more concern, the strand steel risks corrosion failure reducing the expected lifespan of the structure. As tendons are critical structural components, it is important to detect those deficiencies during inspection preferably by a cross …

Post-Overlay Flexible Pavement Performance Modeling And Its Application In Sustainable Asphalt Overlay Policy Making, Chunfu Xin

USF Tampa Graduate Theses and Dissertations

Highway pavement is a critical component of the highway transportation infrastructure. After the construction of a pavement system, pavement condition will deteriorate over time due to a combination effect of material aging, traffic loading, and environmental impact. To restore the pavement performance and to reduce its adverse effects on public users and environment, asphalt overlay activities are conducted frequently during the service life of a pavement. As a key component that bridges the overlay policies with future pavement performance, economic cost and environmental impact, the forecast accuracy of post-overlay pavement performance model is extremely important. However, most of previous studies …

Bond Life Of Structural Epoxy-Concrete Systems Under Accelerated Hygrothermal Aging, Philip W. Hopkins

USF Tampa Graduate Theses and Dissertations

A laboratory study was conducted to investigate possible quantitative and qualitative methods for determining the bond life of structural epoxies externally bonded to concrete substrates. Three concrete mixtures, two surface preparation methods, and three structural epoxies were used creating eighteen combinations of bonded systems. Direct tension (pull-off) specimens were prepared from which a subset was submerged in heated water per a prescribed accelerated aging protocol for up to 200 days. A novel test fixture was designed to facilitate controlled-rate testing of the pull-off specimens. A total of 324 specimens were intermittently removed from submersion exposure and tested without replacement. An …

Influence Of Glass Fiber Reinforced Polymer Wraps On Corrosion Progression Of Bridge Piles In Marine Environments, Shayan Yazdani

USF Tampa Graduate Theses and Dissertations

The Friendship Trail Bridge connecting Tampa to St. Petersburg was demolished in 2016. Thirteen 20 inches. by 20 inches. reinforced concrete piles supporting its superstructure were part of research studies conducted between 2004 and 2008 to explore the role of glass fiber reinforced polymers (GFRP) in corrosion repair. During demolition, piles were typically cut at the pile cap and in the splash zone. The resulting segments varied in length between 3 to 4 ft. These remnants were transported to the University of South Florida (USF) campus for postmortem analysis. The overarching goal was to establish the role of GFRP in …

Enhanced Fluoride Removal In Biosand Filters Using Aluminum Oxide Coated Media And Modified Filter Design, Madison Leigh Rice

USF Tampa Graduate Theses and Dissertations

In 2010, the UN formally stated that access to safe drinking water and sanitation is a human right. Yet, one in three people globally do not have access to safe drinking water. Contaminated drinking water can negatively impact the health of consumers. This is a challenge that disproportionally affects developing regions, where limited access to resources exacerbates the problem. One drinking water contaminant of concern is fluoride. Fluoride is often added in low concentrations to drinking water to enhance consumers’ dental health. However, when water with high concentrations of fluoride is consumed frequently, it can have negative health effects, such …

Implementation Of Large-Scale Anaerobic Digestion Of Food Waste At The University Of South Florida, Karamjit Panesar

USF Tampa Graduate Theses and Dissertations

Food waste represents a major sustainability issue in the United States. Food waste represents 18% of landfill space and is the largest contributor of landfill methane emissions. US EPA’s Food Recovery Hierarchy recommends alternatives to landfilling food waste, including source reduction, food donation and anaerobic digestion.

The Student Green Energy Fund (SGEF) Food Recovery Project aims to follow suggestions outlined by the US EPA Food Recovery Hierarchy to encourage the University of South Florida (USF) to become a zero-waste campus. A multi-disciplinary approach aims to source reduce wasted food, look for opportunities for source reduction and anaerobically digest any remaining …

Enhanced Nitrogen, Organic Matter And Color Removal From Landfill Leachate By Biological Treatment Processes With Biochar And Zeolite, Bisheng Gao

USF Tampa Graduate Theses and Dissertations

Leachate percolating through landfills must be collected and properly treated. However, high concentrations of ammonia (NH4+), refractory organic matter [measured as chemical oxygen demand (COD)], water color and heavy metals in leachate interfere biological processes in conventional wastewater treatment plants. Constructed wetlands (CWs) have been used in the past to treat leachate, but their design and performance has not been properly optimized. In particular, low cost adsorbent materials, such as zeolite and biochar, have the potential to adsorb ammonia and organic compounds, respectively. This increases their retention in the wetland and reduces their toxicity to microorganisms and plants in the …

Low-Grade Kaolin Clay Natural Resource For Use As A Supplementary Cementitious Material In Structural Concrete Elements, Brandon X. Lorentz

USF Tampa Graduate Theses and Dissertations

At the turn of the century, low-grade kaolin clay (LGK) was presented as a widely available and potential natural resource of supplementary cementitious materials (SCM) for producing high performance concretes. In using LGK as an SCM, clinker production is reduced, aiding environmental concerns with associated CO2 emissions. These types of clays have very heterogeneous mineralogy and microstructural characteristics, causing unique influences on concrete structural and flow performance, although these influences are not well understood. This research studies LGK natural to the state of Florida and assesses their potential use as high performance SCM.

Ten kaolin clays were obtained through a …