Engineering Commons^™

Brain-Inspired Spatio-Temporal Learning With Application To Robotics, Thiago André Ferreira Medeiros

USF Tampa Graduate Theses and Dissertations

The human brain still has many mysteries and one of them is how it encodes information. The following study intends to unravel at least one such mechanism. For this it will be demonstrated how a set of specialized neurons may use spatial and temporal information to encode information. These neurons, called Place Cells, become active when the animal enters a place in the environment, allowing it to build a cognitive map of the environment. In a recent paper by Scleidorovich et al. in 2022, it was demonstrated that it was possible to differentiate between two sequences of activations of a …

Brain-Inspired Spatio-Temporal Learning With Application To Robotics, Thiago André Ferreira Medeiros

USF Tampa Graduate Theses and Dissertations

The human brain still has many mysteries and one of them is how it encodes information. The following study intends to unravel at least one such mechanism. For this it will be demonstrated how a set of specialized neurons may use spatial and temporal information to encode information. These neurons, called Place Cells, become active when the animal enters a place in the environment, allowing it to build a cognitive map of the environment. In a recent paper by Scleidorovich et al. in 2022, it was demonstrated that it was possible to differentiate between two sequences of activations of a …

Integration Of Algae And Biomass Processes To Synthesize Renewable Bioproducts For The Circular Economy, Jessica Martin

USF Tampa Graduate Theses and Dissertations

Rapid population growth and global industrialization have substantially heightened the demand for fossil-based fuels and products in various sectors of the global economy, including energy production, transportation fuels, and as raw materials for petrochemicals. The intense consumption of fossil fuels has caused immense environmental impacts, especially pertaining to carbon dioxide emissions. Shifting to renewable feedstocks (raw materials) is expected to reduce these emissions by lowering the carbon footprint of fuels and products compared to traditional fossil-derived alternatives. This transition aligns with the goal of creating a sustainable and circular economy, emphasizing efficient resource use, and reducing waste generation through recycling …

Integration Of Algae And Biomass Processes To Synthesize Renewable Bioproducts For The Circular Economy, Jessica Martin

USF Tampa Graduate Theses and Dissertations

Rapid population growth and global industrialization have substantially heightened the demand for fossil-based fuels and products in various sectors of the global economy, including energy production, transportation fuels, and as raw materials for petrochemicals. The intense consumption of fossil fuels has caused immense environmental impacts, especially pertaining to carbon dioxide emissions. Shifting to renewable feedstocks (raw materials) is expected to reduce these emissions by lowering the carbon footprint of fuels and products compared to traditional fossil-derived alternatives. This transition aligns with the goal of creating a sustainable and circular economy, emphasizing efficient resource use, and reducing waste generation through recycling …

Swelling Induced Buckling Of Photopatterned Hydrogel Beams, Chinar Yogesh Kokaje

USF Tampa Graduate Theses and Dissertations

The main goal of this study was to learn more about swelling induced buckling of surface-attached gel lines photo-patterned from thermally responsive polymers. A library of 10 different polymer compositions was synthesized using methacryloyloxybenzophenone (MABP) as the photo-cross-linking monomer. For each of the polymers, a series of beam-like patterns were prepared on polystyrene tissue culture dishes by first depositing a known amount of polymer into the tissue culture dish followed by pattern generation using a photo-lithography mask with line widths of 10, 20, 30, 50, and 80 μm. The target height of each polymer line was 100 μm. After development …

Swelling Induced Buckling Of Photopatterned Hydrogel Beams, Chinar Yogesh Kokaje

USF Tampa Graduate Theses and Dissertations

The main goal of this study was to learn more about swelling induced buckling of surface-attached gel lines photo-patterned from thermally responsive polymers. A library of 10 different polymer compositions was synthesized using methacryloyloxybenzophenone (MABP) as the photo-cross-linking monomer. For each of the polymers, a series of beam-like patterns were prepared on polystyrene tissue culture dishes by first depositing a known amount of polymer into the tissue culture dish followed by pattern generation using a photo-lithography mask with line widths of 10, 20, 30, 50, and 80 μm. The target height of each polymer line was 100 μm. After development …

Syntheses, Photophysics, & Application Of Porphyrinic Metal-Organic Frameworks, Zachary L. Magnuson

USF Tampa Graduate Theses and Dissertations

Porphyrins are a group of heterocyclic macrocycles that play crucial roles in various biological processes such as electron transfer, catalysis, and sensing. Hemoglobin, which carries oxygen in the blood of mammals, and chlorophyll, which drives photosynthesis in plants and algae, are both porphyrins. The ability of porphyrins to bind metal ions and their unique electronic and photophysical properties make them an excellent platform for designing functional materials for various applications, often drawing inspiration from their function in nature. Metal-organic frameworks (MOFs) are a class of porous materials that have been extensively studied in recent years due to their high surface …

Syntheses, Photophysics, & Application Of Porphyrinic Metal-Organic Frameworks, Zachary L. Magnuson

USF Tampa Graduate Theses and Dissertations

Porphyrins are a group of heterocyclic macrocycles that play crucial roles in various biological processes such as electron transfer, catalysis, and sensing. Hemoglobin, which carries oxygen in the blood of mammals, and chlorophyll, which drives photosynthesis in plants and algae, are both porphyrins. The ability of porphyrins to bind metal ions and their unique electronic and photophysical properties make them an excellent platform for designing functional materials for various applications, often drawing inspiration from their function in nature. Metal-organic frameworks (MOFs) are a class of porous materials that have been extensively studied in recent years due to their high surface …

Mechanisms Contributing To Hydrogen-Influenced Early Failure Of Bridge Tendons, David Dukeman

USF Tampa Graduate Theses and Dissertations

Failures in post-tensioned tendons have occurred without warning due to fractures in the high-strength steel strands. These strands are cold-drawn to increase their strength while still retaining the preferential ductile mode of fracture. Recently, a tendon failure that occurred in an upper deviation block of the I-526 James B. Edwards bridge crossing the Wando river showed signs of corrosion and potentially another method of failure, hydrogen embrittlement. One proposed source of hydrogen is through galvanic coupling that may exist between the galvanized steel duct and the steel strands. This coupling, if substantial, can promote hydrogen evolution at the steel strand's …

Mechanisms Contributing To Hydrogen-Influenced Early Failure Of Bridge Tendons, David Dukeman

USF Tampa Graduate Theses and Dissertations

Failures in post-tensioned tendons have occurred without warning due to fractures in the high-strength steel strands. These strands are cold-drawn to increase their strength while still retaining the preferential ductile mode of fracture. Recently, a tendon failure that occurred in an upper deviation block of the I-526 James B. Edwards bridge crossing the Wando river showed signs of corrosion and potentially another method of failure, hydrogen embrittlement. One proposed source of hydrogen is through galvanic coupling that may exist between the galvanized steel duct and the steel strands. This coupling, if substantial, can promote hydrogen evolution at the steel strand's …

Interdependency Between Water And Road Infrastructures: Cases And Impacts, Shihab Uddin

USF Tampa Graduate Theses and Dissertations

This dissertation studies the interdependency between road and water infrastructures and associated interdependency impact on these two critical infrastructure systems. Critical infrastructures and the interdependency among these infrastructures have gained much attention recently because of its growing complexity, importance, and vulnerability to natural and man-made threats. In response, researchers have spent significant effort to study these infrastructures individually as well as when they are interdependent to understand complex interdependency relationship and to figure out ways to make these infrastructures more reliable, robust, and resilient. However, water and road infrastructure systems have not been studied as vastly as other critical infrastructures …

Interdependency Between Water And Road Infrastructures: Cases And Impacts, Shihab Uddin

USF Tampa Graduate Theses and Dissertations

This dissertation studies the interdependency between road and water infrastructures and associated interdependency impact on these two critical infrastructure systems. Critical infrastructures and the interdependency among these infrastructures have gained much attention recently because of its growing complexity, importance, and vulnerability to natural and man-made threats. In response, researchers have spent significant effort to study these infrastructures individually as well as when they are interdependent to understand complex interdependency relationship and to figure out ways to make these infrastructures more reliable, robust, and resilient. However, water and road infrastructure systems have not been studied as vastly as other critical infrastructures …

Novel Systems Engineering Framework Analysis Of Photovoltaic Models And Equations, Peter R. Michael

USF Tampa Graduate Theses and Dissertations

This dissertation analyzes Photovoltaic PV equations and models for silicon based systems from a Systems Engineering framework. Background information includes an introduction, a summary of the state of PV use, a brief history of photovoltaics, and the detailed derivation of equations that enable the finding of the PV parameters contained in the PV models.The novel inquiry, leveraging systems engineering frameworks, includes three areas useful in analyzing PV equations and models. The first is a statistical verification of common simplifications of PV equations at the primary conditions of short circuit, open circuit, and maximum power. Additional analysis shows other simplifications that …

Novel Systems Engineering Framework Analysis Of Photovoltaic Models And Equations, Peter R. Michael

USF Tampa Graduate Theses and Dissertations

This dissertation analyzes Photovoltaic PV equations and models for silicon based systems from a Systems Engineering framework. Background information includes an introduction, a summary of the state of PV use, a brief history of photovoltaics, and the detailed derivation of equations that enable the finding of the PV parameters contained in the PV models.The novel inquiry, leveraging systems engineering frameworks, includes three areas useful in analyzing PV equations and models. The first is a statistical verification of common simplifications of PV equations at the primary conditions of short circuit, open circuit, and maximum power. Additional analysis shows other simplifications that …

Deep Learning-Based Automatic Stereology For High- And Low-Magnification Images, Hunter Morera

USF Tampa Graduate Theses and Dissertations

Quantification of the true number of stained cells in specific brain regions is an important metric in many fields of biomedical research involving cell degeneration, cytotoxicology, cellular inflammation, and drug development for a wide range of neurological disorders and mental illnesses. Unbiased stereology is the current state-of-the-art method for collecting the cell count data from tissue sections. These studies require trained experts to manually focus through a z-stack of microscopy images and count (click) on a hundred or more cells per case, making this approach time consuming (~1 hour per case) and prone to human error (i.e., inter-rater variability). Thus, …

Deep Learning-Based Automatic Stereology For High- And Low-Magnification Images, Hunter Morera

USF Tampa Graduate Theses and Dissertations

Quantification of the true number of stained cells in specific brain regions is an important metric in many fields of biomedical research involving cell degeneration, cytotoxicology, cellular inflammation, and drug development for a wide range of neurological disorders and mental illnesses. Unbiased stereology is the current state-of-the-art method for collecting the cell count data from tissue sections. These studies require trained experts to manually focus through a z-stack of microscopy images and count (click) on a hundred or more cells per case, making this approach time consuming (∼1 hour per case) and prone to human error (i.e., inter-rater variability). Thus, …

Wastewater Treatment Using Encapsulated Chabazite In Polyvinyl Alcohol-Sodium Alginate Hydrogel Biofilm Carriers, Susieanna Nevada Persaud

USF Tampa Graduate Theses and Dissertations

Nitrogen discharge from wastewater is a global issue and with increased urbanization as well as industrialization, it has become even more essential to develop more efficient wastewater treatment systems. The dominant form of nitrogen in wastewater is ammonium. Biological oxidation of ammonium to nitrite and nitrate is the first step in biological nitrogen removal processes. If left untreated, nitrogen can cause toxicity to aquatic life, unsafe changes in water quality, and eutrophication.

Biofilm carriers can help to improve the efficiency of traditional activated sludge wastewater treatment systems by reducing operating costs and reducing hydraulic retention time. Biofilm carriers also promote …

Wastewater Treatment Using Encapsulated Chabazite In Polyvinyl Alcohol-Sodium Alginate Hydrogel Biofilm Carriers, Susieanna Nevada Persaud

USF Tampa Graduate Theses and Dissertations

Nitrogen discharge from wastewater is a global issue and with increased urbanization as well as industrialization, it has become even more essential to develop more efficient wastewater treatment systems. The dominant form of nitrogen in wastewater is ammonium. Biological oxidation of ammonium to nitrite and nitrate is the first step in biological nitrogen removal processes. If left untreated, nitrogen can cause toxicity to aquatic life, unsafe changes in water quality, and eutrophication.

Biofilm carriers can help to improve the efficiency of traditional activated sludge wastewater treatment systems by reducing operating costs and reducing hydraulic retention time. Biofilm carriers also promote …

Hurricanes And Tropical Storms’ Impact On Water Quality In Lake Okeechobee, Florida, Daniela Vasquez Diaz

USF Tampa Graduate Theses and Dissertations

Hurricanes are natural events with catastrophic outcomes, while climate change's effects on their intensity and frequency remain discussed. However, it is crucial to analyze these through models and statistics to understand their behavior and impact on the basins. Particularly in lakes on tropical coasts since disruptive events such as hurricanes tend to be highly affected. Lake Okeechobee is a unique lake located in Florida and one of the largest freshwater lakes. The lake and some of its significant stations are the locations chosen to perform the investigation. The main focus of the investigation is determining the effect that hurricanes have …

Hurricanes And Tropical Storms’ Impact On Water Quality In Lake Okeechobee, Florida, Daniela Vasquez Diaz

USF Tampa Graduate Theses and Dissertations

Hurricanes are natural events with catastrophic outcomes, while climate change's effects on their intensity and frequency remain discussed. However, it is crucial to analyze these through models and statistics to understand their behavior and impact on the basins. Particularly in lakes on tropical coasts since disruptive events such as hurricanes tend to be highly affected. Lake Okeechobee is a unique lake located in Florida and one of the largest freshwater lakes. The lake and some of its significant stations are the locations chosen to perform the investigation. The main focus of the investigation is determining the effect that hurricanes have …

Analyzing Multi-Robot Leader-Follower Formations In Obstacle-Laden Environments, Zachary J. Hinnen

USF Tampa Graduate Theses and Dissertations

Observations in biological formation from nature likes flocks of birds, herds of mammals and packs of wolves have inspired the innovation of robotic architectures. This thesis presents an approach that aims to use robotic systems to mimic leader-follower behaviors in the navigation and formation of sparse and dense environments. The goal of this work is to extend and further analyze the original work of Weitzenfeld et al [3] to evaluate new swarm and pack based multi-robot architectures with the inclusion of obstacle avoidance and variations in group formations. The multiple robot architecture is based off a wolf pack with a …

Knowledge Integration In Domain-Informed Machine Learning And Multi-Scale Modeling Of Nonlinear Dynamics In Complex Systems, Phat K. Huynh

USF Tampa Graduate Theses and Dissertations

Nonlinear dynamical systems have been extensively used to model various phenomena in the changing world around us, especially in science and engineering fields. Thanks to breakthrough advancements in sensing technologies, an increasingly high volume of multi-modal sensor data has been collected, which enables us gain better insights into complex systems dynamics and build sophisticated data-driven machine-learning-based dynamic models without having the access to the underlying governing equations. However, integrating domain-specific knowledge in machine learning algorithms remains pivotal for various reasons: it promises enhanced predictive accuracy, better model interpretability, and increased generalizability. This dissertation delves into three core research questions, each …

Analyzing Multi-Robot Leader-Follower Formations In Obstacle-Laden Environments, Zachary J. Hinnen

USF Tampa Graduate Theses and Dissertations

Observations in biological formation from nature likes flocks of birds, herds of mammals and packs of wolves have inspired the innovation of robotic architectures. This thesis presents an approach that aims to use robotic systems to mimic leader-follower behaviors in the navigation and formation of sparse and dense environments. The goal of this work is to extend and further analyze the original work of Weitzenfeld et al [3] to evaluate new swarm and pack based multi-robot architectures with the inclusion of obstacle avoidance and variations in group formations. The multiple robot architecture is based off a wolf pack with a …

Knowledge Integration In Domain-Informed Machine Learning And Multi-Scale Modeling Of Nonlinear Dynamics In Complex Systems, Phat K. Huynh

USF Tampa Graduate Theses and Dissertations

Nonlinear dynamical systems have been extensively used to model various phenomena in the changing world around us, especially in science and engineering fields. Thanks to breakthrough advancements in sensing technologies, an increasingly high volume of multi-modal sensor data has been collected, which enables us gain better insights into complex systems dynamics and build sophisticated data-driven machine-learning-based dynamic models without having the access to the underlying governing equations. However, integrating domain-specific knowledge in machine learning algorithms remains pivotal for various reasons: it promises enhanced predictive accuracy, better model interpretability, and increased generalizability. This dissertation delves into three core research questions, each …

Effects Of Downdrag On Pile Performance, Ruthvik Pendyala

USF Tampa Graduate Theses and Dissertations

The behavior of piles under varying load conditions has sparked significant interest and research within the geotechnical engineering field. Specifically, in the context of MSE wall-type embankments, piles are installed before embankment construction commences. In these scenarios, soil settlement beneath the embankment initiates following pile installation, consequently generating downward lateral shear loads on the piles, known as downdrag.

Research pertaining to the downdrag phenomenon in cohesionless granular soils is limited. Hence, the primary focus of this study revolves around examining the impact of downdrag on pile performance in sandy soils using numerical modeling as the investigative approach. To accomplish this, …

Effects Of Downdrag On Pile Performance, Ruthvik Pendyala

USF Tampa Graduate Theses and Dissertations

The behavior of piles under varying load conditions has sparked significant interest and research within the geotechnical engineering field. Specifically, in the context of MSE wall-type embankments, piles are installed before embankment construction commences. In these scenarios, soil settlement beneath the embankment initiates following pile installation, consequently generating downward lateral shear loads on the piles, known as downdrag.

Research pertaining to the downdrag phenomenon in cohesionless granular soils is limited. Hence, the primary focus of this study revolves around examining the impact of downdrag on pile performance in sandy soils using numerical modeling as the investigative approach. To accomplish this, …

The Development Of A General Watershed - Highway Mathematical Model, Robert W. Higgins

USF Tampa Graduate Theses and Dissertations

No abstract provided.

The Aging Workforce: How It Relates To Incident Rates Within A Distribution Warehouse And A Chemical Manufacturing Building, Elisabeth V. Jones

USF Tampa Graduate Theses and Dissertations

Over the past 20 years or so, the average age of the global population has slowly increased. This is due to low birth rates as well as increased life expectancy. With this global population aging, there has also been a shift in the global labor market causing a trend termed the “aging workforce.” However, with the aging workforce comes a new set of issues for the health and safety professional because they create new hazards. This is due mostly because of the body undergoing physical, psychological, and cognitive decline as someone ages which causes decreased capabilities. Thus, the purpose of …

The Aging Workforce: How It Relates To Incident Rates Within A Distribution Warehouse And A Chemical Manufacturing Building, Elisabeth V. Jones

USF Tampa Graduate Theses and Dissertations

Over the past 20 years or so, the average age of the global population has slowly increased. This is due to low birth rates as well as increased life expectancy. With this global population aging, there has also been a shift in the global labor market causing a trend termed the “aging workforce.” However, with the aging workforce comes a new set of issues for the health and safety professional because they create new hazards. This is due mostly because of the body undergoing physical, psychological, and cognitive decline as someone ages which causes decreased capabilities. Thus, the purpose of …

Cyber-Physical Multi-Robot Systems In A Smart Factory: A Networked Ai Agents Approach, Zixiang Nie

USF Tampa Graduate Theses and Dissertations

This dissertation focuses on addressing the technical challenges of non-stationarity in smart factories through the use of cyber-physical AI agents. Industry 4.0 and smart manufacturing with smart factories as a central role, have a growing demand for Just-in-Time (JIT) and on-demand production, as well as mass customization—all while maintaining high productivity, resource efficiency and resilience. This research positions Multi-Robot Systems (MRS)-driven smart factories. The heterogeneous production and transportation robots in an MRS collaborate to form multiple real-time adjusted production flows achieving the flexibility to accommodate such on-demand, mass customization.

However, the implementation of MRS introduces new sets of challenges, including …