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Full-Text Articles in Engineering

Miniaturized Battery Powered Air Quality Monitoring System, Bryan Chacon Aug 2022

Miniaturized Battery Powered Air Quality Monitoring System, Bryan Chacon

All Theses

In this work, an air quality monitoring system was developed using various sensors that measure specific air quality parameters, including Volatile Organic Compounds, Carbon Dioxide, particulate matter of varying sizes, ambient pressure, humidity, and temperature. This system is based off a Particle micro-controller, Boron LTE CAT-M1 which allows for cellular connectivity for real-time data transmission. It is powered by a 3.7 Volt Li-Po battery and has a miniaturized design which allows for portability. This data is processed through an Internet of Things software provider that allows for the device to be connected and accessed to and from anywhere in the …


Generating Sex Trafficking Networks From Text Documents, Maria Diaz Aug 2022

Generating Sex Trafficking Networks From Text Documents, Maria Diaz

All Theses

Qualitative coding is a long and strenuous process that requires a well-skilled investigator. Natural language processing techniques have made leaps and bounds as far as usability and application domain, although it does not work for every task. In this work, we have created a natural language processing framework to help qualitative coders automatically obtain the nodes and node arcs from federal case files, dockets, and indictments within a sex trafficking network. The produced nodes and arcs allows us to perform network modeling by providing us with the information needed to create network structures that can then be used for interdiction …


Variations In Surgeon-Applied Loads During Passive Range Of Motion Following Total Knee Replacement With Relevance To Computational Modeling, Cj Bakle Ii Jun 2022

Variations In Surgeon-Applied Loads During Passive Range Of Motion Following Total Knee Replacement With Relevance To Computational Modeling, Cj Bakle Ii

All Theses

Total knee replacement (TKR) is generally considered a successful treatment for musculoskeletal disorders of the knee. However, as many as 20% of patients report some dissatisfaction in their physical function after TKR. And approximately 50% of early revisions needed to address conditions related to component alignment and soft tissue tension to stabilize the knee. During TKR, surgeons manually perform passive range of motion (ROM) assessments to gain feedback perceived as tension in ligaments and other soft tissues. Such assessments are highly subjective and rely on the surgeon's perception of soft tissue tension rather than quantitative objective means. The variability in …


Insect Antennae As Bioinspirational Superstrong Fiber-Based Microfluidics, Griffin J. Donley May 2022

Insect Antennae As Bioinspirational Superstrong Fiber-Based Microfluidics, Griffin J. Donley

All Theses

Nature is frequently turned to for inspiration for the creation of new materials. Insect antennae are hollow, blood-filled fibers with complex shape, and are cantilevered at the head. The antenna is muscle-free, but the insect can controllably flex, twist, and maneuver it laterally. To explain this behavior, a comparative study of structural and tensile properties of the antennae of Periplaneta americana (American cockroach), Manduca sexta (Carolina hawkmoth), and Vanessa cardui (painted lady butterfly) was performed. These antennae demonstrate a range of distinguishable tensile properties, responding either as brittle fibers (Manduca sexta) or strain-adaptive fibers that stiffen when stretched (Vanessa cardui …


Near-Earth Ion Irradiation Effects On Functional Ceramic Materials: A Combined Experimental-Monte Carlo Approach, William J. Sands May 2022

Near-Earth Ion Irradiation Effects On Functional Ceramic Materials: A Combined Experimental-Monte Carlo Approach, William J. Sands

All Theses

The near-Earth space radiation environment is a complex system that creates a harmful environment for materials to operate in. Motivated by the search for using optical defects as an indicator of radiation damage, five single-crystal functional ceramic materials were selected to undergo ion irradiation at conditions found in the near-Earth space environment. Due to the complex nature of ion irradiation effects in ceramic materials, a host of calculations and experimental characterization methods were used. Calculations using the 2013 SRIM code were used to evaluate the ion projected range and the type and number of defects (vacancies) created by ion irradiation. …


Investigations Of External Resources And The Impact Of Imaging On Patient Flow In The Emergency Department, Marisa Shehan May 2022

Investigations Of External Resources And The Impact Of Imaging On Patient Flow In The Emergency Department, Marisa Shehan

All Theses

The problems associated with Emergency Department (ED) crowding are numerous, varied, and complex. Though overcrowded Emergency Departments are frequently attributed to overcrowded hospitals, crowding is also impacted by bottlenecks in patient flow. While discrete-event simulation (DES) is commonly used to model ED flow, external resources are typically excluded from these models due to their complexity and the limited amount of known information for these processes. Instead, external resources such as consults, labs, and imaging are modeled using estimation and/or educated guesswork. In this study, the impact of imaging on patient flow was assessed through data analysis of specific imaging factors, …


A Study On Effect Of Manufacturing Parameters On Morphology Of A356 Aluminum Foam, Nikhil Nanabhau Mahajan May 2022

A Study On Effect Of Manufacturing Parameters On Morphology Of A356 Aluminum Foam, Nikhil Nanabhau Mahajan

All Theses

Metal foams have shown an excellent promise for usage as multifunctional material concerning research & development in the last 20 years. They provide remarkable mechanical as well as physical properties being lightweight. Open-cell metal foams have already been used in sound and noise absorption. Open-cell metal foams are outstanding for use in heat exchangers, filters, and many more applications, while closed-cell foams show excellent characteristics in impact energy absorptions. Closed-cell metal foams have higher energy absorption than their solid parent metal as they convert most of the impact energy into deformation energy. Metal foams have been used as prominent safeguard …


Improving Intelligent Transportation Safety And Reliability Through Lowering Costs, Integrating Machine Learning, And Studying Model Sensitivity, Cavender Holt May 2022

Improving Intelligent Transportation Safety And Reliability Through Lowering Costs, Integrating Machine Learning, And Studying Model Sensitivity, Cavender Holt

All Theses

As intelligent transportation becomes increasingly prevalent in the domain of transportation, it is essential to understand the safety, reliability, and performance of these systems. We investigate two primary areas in the problem domain. The first area concerns increasing the feasibility and reducing the cost of deploying pedestrian detection systems to intersections in order to increase safety. By allowing pedestrian detection to be placed in intersections, the data can be better utilized to create systems to prevent accidents from occurring. By employing a dynamic compression scheme for pedestrian detection, we show the reduction of network bandwidth improved by 2.12× over the …


Interdiction Models To Disrupt The Operations Of Sex Trafficking And Other Forced Illicit Labor Networks, Michael T. Clark May 2022

Interdiction Models To Disrupt The Operations Of Sex Trafficking And Other Forced Illicit Labor Networks, Michael T. Clark

All Theses

Sex traffickers often force their victims to work in both commercial sex markets and perform other illicit activities (e.g., drug dealing, theft, and fraud). Current literature has failed to address interdiction models that aim to disrupt all components of a sex traffickers’ operation, including these other illicit activities. In this thesis, we present a interdiction problem, and its single-level linear optimization reformulation, to reduce the profit of a human trafficking network concurrently operating in the commercial sex market and other illicit activity markets. Our novel formulation aims to investigate the practical implications of interdiction decisions made to disrupt a human …


Addressing The Performance Of Distance Relays In Presence Of Inverter Based Resources, Prabin Adhikari May 2022

Addressing The Performance Of Distance Relays In Presence Of Inverter Based Resources, Prabin Adhikari

All Theses

The transition towards clean energy initiatives to reduce global greenhouse emissions and the dependence on fossil fuels requires the interconnection of large-scale renewable energy power plants to high voltage transmission networks via inverters. These inverter interfaced power sources, popularly known as inverter-based resources (IBRs), pose several technical challenges to the existing distance protection infrastructures widely deployed in transmission systems.

Fault characteristics of IBRs are significantly different from those shown by synchronous generators (SGs). With IBRs taking a large share of generation, their increasing penetration at the transmission level causes incorrect operation of existing distance protection schemes designed for systems dominated …


Examining The Different Snap-Through Characteristics Of Bistable Cfrp Composite Laminates, Vishrut Deshpande May 2022

Examining The Different Snap-Through Characteristics Of Bistable Cfrp Composite Laminates, Vishrut Deshpande

All Theses

Bistable carbon fiber composites, whose bistability arises from having asymmetric fiber layouts in different layers, have shown immense potential for use in shape morphing and adaptive structure applications. While many studies in this field focus on these composite laminates’ external shapes at the two stable states, their snap-through behavior of shifting from one stable shape to the other remains a critical aspect to be investigated in complete detail. Moreover, symmetric loading conditions have been extensively studied based on the classical lamination theory, but the asymmetric loading conditions received far less attention. Therefore, this study examines an asymmetric, localized point load …


Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano May 2022

Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano

All Theses

Toxoplasma gondii is a pathogenic microorganism that is currently a threat to public health. Understanding the fate and transport of T. gondii through the soil and groundwater is vital in determining the risk it poses to water resources and human health. The physico-chemical interactions between the groundwater and the bio colloid within an aquifer will dictate its mobility and its ability to infect humans. This research examines how various naturally occurring groundwater chemistries containing organic compounds and monovalent and divalent salt solutions will alter the fate and transport of T. gondii. Solutions containing various concentrations of humic acid, fulvic …


Toward Sustainable Urban Food Production: Integrating Hydroponic Cultivation With Wastewater Reuse, Amanda Tan May 2022

Toward Sustainable Urban Food Production: Integrating Hydroponic Cultivation With Wastewater Reuse, Amanda Tan

All Theses

The growing crisis of freshwater scarcity together with the increasing global food demand directs attention to the need for alternative water sources for agriculture. The research presented here engages this need by carrying out indoor cultivation of food crops in Nutrient Film Technique (NFT) hydroponic systems using residential wastewater. Randomized single factor experimental designs were used to investigate the physiochemical and microbiological makeup of the hydroponic nutrient solution throughout the cultivation cycle and their relationship with different plant development parameters.

For agricultural wastewater reuse to be of low risk to human health there must be some advancement in pathogen monitoring …


Nonlinear Optical Microscopy Assessment Of Tissue Structure And Chondrocyte Viability Of Articular Cartilage, Michael Le May 2022

Nonlinear Optical Microscopy Assessment Of Tissue Structure And Chondrocyte Viability Of Articular Cartilage, Michael Le

All Theses

Articular cartilage functions to protect the ends of bones by providing a surface that can withstand compressive forces and minimize friction during movement. Collagen fibers form the organizational backbone of the extracellular matrix (ECM) in cartilage. Proteoglycans within the ECM function to retain water and provide the tissue with the swelling pressure needed to withstand compressional forces. Chondrocytes, the only type of cell found in articular cartilage, produces these collagen fibers and proteoglycans to maintain the tissue structure and function. Significant injuries to articular cartilage can damage the chondrocytes and disrupt their ability to maintain homeostasis in the tissue. Therefore, …


Structural Evolution During Synthesis And Annealing Of Platinum-Nickel Bimetallic Nanoparticles, Xiner Lu May 2022

Structural Evolution During Synthesis And Annealing Of Platinum-Nickel Bimetallic Nanoparticles, Xiner Lu

All Theses

In the past years, there has been an increasing interest in synthesizing Pt alloy nanocrystals to achieve high catalytic performance for energy-related applications. Pt-Ni nanoparticles (NPs) have shown high electrocatalytic activity for electrocatalysis and thermal catalysis. However, the stability of surface structures and compositions still needs to be improved to obtain better long-term catalytic stability. It is noted that thermal annealing can adjust the surface structures and compositions to improve the stability. Transmission electron microscopy (TEM) plays a vital role in characterizing the morphology, structure, and composition of nanoparticles. Specifically, the utilization of in situ TEM can allow for observing …


Floating Treatment Wetlands For Brackish Waters: Plant Selection And Nutrient Uptake Potential., Andrea Landaverde May 2022

Floating Treatment Wetlands For Brackish Waters: Plant Selection And Nutrient Uptake Potential., Andrea Landaverde

All Theses

Brackish water bodies in coastal regions provide critical ecosystem services that support human and environmental health. Anthropogenic activities such as agricultural and industrial activities, construction, urban settlements, and tourism contribute to increased inputs of nitrogen (N) and phosphorus (P) in brackish coastal ecosystems. Excess nutrients can lead to impaired water quality and affect marine organisms. Floating treatment wetlands (FTWs) are a vegetated-base technology used to remove contaminants from water column, that has been mainly studied and applied in freshwater systems. Application of FTWs in brackish systems requires further investigation, as high salinity in brackish waters could result in toxicity to …


Investigating The Effects Of Sic Abrasive Particles On Friction Element Welding, Gaurav Awate May 2022

Investigating The Effects Of Sic Abrasive Particles On Friction Element Welding, Gaurav Awate

All Theses

The growing demands on reducing the harmful emissions from automobiles have forced automakers to reduce the weight of the vehicle. The increasing demands on improving the fuel economy also has challenged automotive manufacturers to make the vehicle as lightweight as possible. However, the challenge is also to ensure that the vehicle meets safety standards. For the vehicle to meet these standards, it needs to be of adequate strength as well. Automotive manufacturers have adopted a strategy of using multi-material construction to achieve the target. But with multi-material construction comes the requirement of advanced joining techniques that are capable of joining …


The Role Of Consumers In The Adoption Of Alternatively Fueled Vehicles And Mitigation Of Vulnerabilities Associated With Electric Vehicle Charging, Elaina D. Stuckey May 2022

The Role Of Consumers In The Adoption Of Alternatively Fueled Vehicles And Mitigation Of Vulnerabilities Associated With Electric Vehicle Charging, Elaina D. Stuckey

All Theses

Electric vehicles have the potential to replace traditional automobiles as the primary form of transportation. Despite major improvements in technology and an expanding focus on climate change making electric vehicles more practical than ever before, consumers are still wary of adopting them for legitimate reasons such as costs and charging infrastructure. Therefore, a concerted effort must be made to persuade individuals and companies to adopt this beneficial technology to reduce the carbon footprint and catalyze the construction of important charging infrastructure.

Though there are a multitude of benefits to adopting electric vehicles, there will be some negative effects on the …


Quantifying Shear Stresses In Tissue Engineered Aortic Heart Valves, Raj Nitin Dave May 2022

Quantifying Shear Stresses In Tissue Engineered Aortic Heart Valves, Raj Nitin Dave

All Theses

Present heart valve prosthesis have limitations such as capability to grow, repair and remodel post implantation. Tissue engineering offers to be a promising alternative to overcome these limitations. Maturation of seeded human cells on the valve subjected to favorable growth conditions in the bioreactor is critical to the success of tissue engineered heart valves. Mechanical stress and strain which results from the pressure and flow conditions in the bioreactor plays a critical role on the developing valve tissue and are currently unknown. The goal of this research is to relate the magnitude of wall shear stress (WSS) within the heart …


Battery Energy Storage System Mitigation Strategies For The Grid Impacts Of Electric Vehicle Charging Infrastructure, Chance Stowe May 2022

Battery Energy Storage System Mitigation Strategies For The Grid Impacts Of Electric Vehicle Charging Infrastructure, Chance Stowe

All Theses

The face of transportation is changing as a greater number of companies and private individuals switch from traditional automobiles to electric vehicles. This surge has been bolstered by improvements in technology, increased marketing, and a heightened focus on the role humanity plays in climate change. This advancement brings a growth in electrical demand caused by the charging loads of these vehicles. Due to the quick, sudden rise of this technology, the utility energy industry is still in the early stages of preparing for electric vehicle loads beyond the traditional load growth.

Though the technology for battery energy storage has been …


Fabrication Of Hydrogel Microparticles For Acute Treatment Of Penetrating Brain Injuries, Isabell Foulger May 2022

Fabrication Of Hydrogel Microparticles For Acute Treatment Of Penetrating Brain Injuries, Isabell Foulger

All Theses

Traumatic brain injuries (TBIs) are a type of acquired head trauma that results from an external force to the head. The development and severity of the secondary injury increases the risk of neurodegeneration and reduced cognitive recovery. Glucocorticoids are potent antiinflammatory therapeutics that have been investigated for potential treatment of TBIs, strokes, and other neuroinflammatory pathologies. However, their clinical application has been limited due to their ability to induce a variety of side effects, including adrenal suppression, edema, and reduced plasticity of the hippocampus. The use of a localized drug delivery system would overcome these systemic concerns. In previous studies, …


Mechanochromic Tunable Emissions Of Hydrogel Encapsulated Radioluminescent Crystalline Colloidal Arrays, Sarah Mell May 2022

Mechanochromic Tunable Emissions Of Hydrogel Encapsulated Radioluminescent Crystalline Colloidal Arrays, Sarah Mell

All Theses

Crystalline colloidal arrays (CCAs) are periodic dielectric arrays composed of monodisperse, negatively charged nanoparticles with unique optical characteristics. Poly(styrene-co-propargyl acrylate) (PS-PA) based copolymer nanoparticles synthesized via an emulsion polymerization form the basis of the CCAs in this work. The negatively charged surfaces result in the colloidal nanoparticles self-assembling into a face-centered cubic (fcc) crystal-like structure. The long-range order and spatial periodicity of the array result in a rejection wavelength, characteristic of CCAs, in which a specific wavelength of light is forbidden from propagating throughout the optical system. The CCAs exhibit mechanochromism through a rejection wavelength shift corresponding to a change …


Design Of A Four Channel Pulsatile Perfusion Bioreactor For Ex-Vivo Study Of Vascular Grafts, Thomas M. Fair May 2022

Design Of A Four Channel Pulsatile Perfusion Bioreactor For Ex-Vivo Study Of Vascular Grafts, Thomas M. Fair

All Theses

Cardiovascular diseases are the leading cause of death in the United States. Atherosclerosis in peripheral arteries is a major contributing factor. Autologous saphenous vein grafts are the most common bypass grafts for treating peripheral artery diseases. A quarter of these grafts fail within a year, and around half have failed within 10 years of the initial surgery. Graft failure is attributed to the development of intimal hyperplasia indicated by the migration and proliferation of vascular smooth muscle cells, fibroblasts, and the deposition of extracellular proteins.

Increases in flow, pressure, the pulse frequency, and the differential of pressure that model an …


Fathom In Color: Expansion Of Reproduceable Color In Interference Pattern-Based Printed Motion And Depth Effects, Dovie Jeffcoat May 2022

Fathom In Color: Expansion Of Reproduceable Color In Interference Pattern-Based Printed Motion And Depth Effects, Dovie Jeffcoat

All Theses

Value-added printed embellishments are increasingly sought after as brands compete for consumer attention. Fathom Optics’ method for printing motion and depth effects provides a cost-efficient, reduced waste embellishment option. One of Fathom’s current limitations is producing effects with vibrant color. The current standard practice for producing color Fathom Effects tends to darken and desaturate the final embellishment’s color. This study endeavors to determine how an ink color's components (hue, value and chroma) may determine a Fathom Effect’s contrast or intensity. To achieve this, fifteen color inks were selected to flexographically print the effect patterns. Samples were taken from each color …


An Experimental Analysis Of Thin Sheet Metal Bending By Ultrafast Laser Peen Forming, Bryce J. Tessmann May 2022

An Experimental Analysis Of Thin Sheet Metal Bending By Ultrafast Laser Peen Forming, Bryce J. Tessmann

All Theses

This study demonstrates the viability of femtosecond laser peen forming for bidirectional sheet metal bending. Ultrafast laser forming is a valuable method thanks to its flexibility, negation of springback, no need for a confining or protective layer, and minimalization of thermal degradation in comparison to other forming processes. However, femtosecond lasers have traditionally been believed to be unsuitable for laser forming in comparison to nanosecond lasers, particularly bidirectional bending, because the induced shock waves were expected to be weak. Conversely, in this study it is elucidated that the femtosecond laser-induced shock waves are extremely strong (several hundred GPa) but the …


Portable U-Bent Optical Fiber Biosensor For Detecting Microcystin-Lr, Quan Dio Anh Le May 2022

Portable U-Bent Optical Fiber Biosensor For Detecting Microcystin-Lr, Quan Dio Anh Le

All Theses

Cyanobacteria are the only known prokaryotes that can photosynthesize. Due to their unique ability, they are important entities in the global carbon and nitrogen cycles. However, two factors can turn cyanobacteria into a nuisance. In general, eutrophication is the process that supplies external nutrients that are needed for cyanobacteria blooms into bodies of water from the surrounding environment. Climate warming intensifies this process by producing carbon dioxide, methane, and nitrous oxide. With cyanobacteria blooms occurring worldwide, they are becoming a bigger threat to human health, and there has been increased interest in detecting cyanobacteria and their toxic byproducts.

For instance, …


A Quantitative Comparison Of Algorithmic And Machine Learning Network Flow Throughput Prediction, Cayden Wagner May 2022

A Quantitative Comparison Of Algorithmic And Machine Learning Network Flow Throughput Prediction, Cayden Wagner

All Theses

Applications ranging from video meetings, live streaming, video games, autonomous vehicle operations, and algorithmic trading heavily rely on low latency communication to operate optimally. A solution to fully support this growing demand for low latency is called dual-queue active queue management (AQM). Dual-queue AQM's functionality is reduced without network traffic throughput prediction.

Perhaps due to the current popularity of machine learning, there is a trend to adopt machine learning models over traditional algorithmic throughput prediction approaches without empirical support. This study tested the effectiveness of machine learning as compared to time series forecasting algorithms in predicting per-flow network traffic throughput …


Predictive Performance And Teaming Via The Mist-C Ocean Hierarchy Utilizing Personality And Skills, Brighton H. Owen May 2022

Predictive Performance And Teaming Via The Mist-C Ocean Hierarchy Utilizing Personality And Skills, Brighton H. Owen

All Theses

This thesis seeks to establish and define the individual, the team as an entity, and qualify various metrics to predict team performance. When several individuals come together, they form a team that is often capable of designing and developing concepts beyond the individual on their own by methods of task dispersion, goal orientation, communication, and more. With these teams comes growth and increased performance leading to more efficient processes and better metrics by which performance may be measured. To achieve this, 34 engineering students in the AerosPACE senior design program, which lasted two semesters, were asked to complete surveys in …


Analysis Of The Self-Heating Effect On Unfilled Poly(Methyl Methacrylate) Due To Cyclic Behavior, Muhammed R. Kose May 2022

Analysis Of The Self-Heating Effect On Unfilled Poly(Methyl Methacrylate) Due To Cyclic Behavior, Muhammed R. Kose

All Theses

Poly(methyl methacrylate, (PMMA) has been implemented as part of the supporting structure in complete hip and knee replacements since the 1950s. Known as bone cement while in the body, PMMA is known to undergo compressive and tensile stresses that wear down the bio-compatible barrier and cause pieces to come loose inside the human body. These pieces are then attacked by the body’s own nervous system, leading to inflammation, and eventually necessitating replacement. It has been documented that under cyclic loading PMMA can reach temperatures that start to degrade its tensile capabilities. In this study the potential cause of self-heating was …


Soft Web-Based Continuum Robot Grippers, Anthony Carambia May 2022

Soft Web-Based Continuum Robot Grippers, Anthony Carambia

All Theses

We discuss the potential of soft webs to enhance robotic grasping. Specifically, we explore a novel combination of compliant continuum digits interspersed with a flexible material. The resulting webbed structure offers the potential for new modes of robust and adaptive object grasping. We introduce and describe two webbed grippers featuring alternate modes of actuation: pneumatic muscles and remotely actuated tendons. Experiments with the grippers demonstrate their ability to gently capture small, fragile, and non-cooperative objects.