Engineering Commons^™

Development Of The Navigator: A Lagrangian Smart Sensing System To Characterize Aquatic Ecosystems., Aashish Sanjay Khandelwal

Civil Engineering ETDs

Most freshwater aquatic studies rely on Eulerian monitoring, i.e., water quality and quantity are monitored using grab samples or semi-continuous sensors deployed at fixed cross-sections. While Eulerian monitoring is practical, it provides a limited understanding of spatial and temporal heterogeneity and their effects on environmental processes. This dissertation summarizes the design and application of The Navigator, an alternative Lagrangian monitoring system that offers cost-effective solutions for in-situ, real-time data collection in lotic and lentic freshwater ecosystems such as streams, rivers, ponds, and reservoirs. The Navigator features a suite of methods – an autonomous surface vehicle (ASV) with GPS and LTE …

Towards Sustainable Water Management: Soil Analysis, Modeling, And Sensor Implementation On A Micro-Basin Chile's Los Lagos Region, Tammy N. Huynh

Civil Engineering ETDs

The Los Lagos region of Chile is experiencing ecological and socioeconomic challenges because of climate change. Despite efforts by the agricultural sector to understand and manage water resources, the lack of basic water quantification data affects their ability to effectively plan and implement water management strategies. This research aims to address this critical issue through three key objectives. First, characterize soil properties related to texture and structure in a micro-basin of the Los Lagos region. Secondly, it aims to investigate the hydrologic budget of the micro-basin with an emphasis on soil moisture using the Soil Moisture Routing model (SMR). Lastly, …

High-Power Laser Cooling And Temperature-Dependent Fluorescence Studies Of Ytterbium Doped Silica, Brian Topper

Optical Science and Engineering ETDs

Experimental observation of optical refrigeration using ytterbium doped silica glass in recent years has created a new solution for heat mitigation in high-power laser systems, nonlinear fiber experiments, integrated photonics, and precision metrology. Current efforts of different groups focus on compositional optimization, fiber fabrication, and investigating how much silica can be cooled with a laser. At the start of this work, the best effort in laser cooling ytterbium doped silica saw cooling by 6 K from room temperature. This dissertation follows the experimental efforts that culminated in the increase of this initial record by one order of magnitude. Comprehensive spectroscopic …

Heterochiral Dna Nanotechnology For Biomedical Applications, Tracy L. Mallette

Biomedical Engineering ETDs

In the past 30 years, there have been major advancements on how to treat and diagnose disease because of the improvement and increase in accessibility of sequencing technology. Nucleic acid-based therapeutics can manipulate protein expression. Likewise, pathogens can be identified and detected with single nucleotide specificity. However, the underlying oligonucleotide technology requires protection against natural defense systems that have evolved to destroy foreign nucleic acids. Many chemical modifications that can protect nucleotides also have significant cytotoxic side effects and must be carefully designed into the strands. A novel way to protect against nuclease-mediated degradation is through the use of mirror-image, …

Integrating Sensor Development, Risk Assessment, And Community Engagement To Support Environmental Justice In The Rural Community Of El Tiple, Colombia, David Bahamon Pinzon

All Dissertations

In Colombia, ethnic communities have traditionally been responsible stewards of natural resources. They recognize the importance of these resources for their livelihood, as well as their ancestral and cultural heritage. El Tiple, a rural Afro-Colombian community, has been affected by the incursion of private corporations that promoted the expansion of sugarcane monocrops in their territory. Since the introduction of the monoculture industry, local freshwater sources have been depleted due to intensive water use for irrigation of the sugarcane crops. Additionally, the intensive usage of agrochemicals has been linked with loss of native flora, damages to family farms, and pollution of …

Double Cantilever Beam Mode-I Testing Validation In Large-Scale Additive Manufacturing Carbon Composite, Luis Alfonso Camacho

Open Access Theses & Dissertations

Testing for mechanical properties for additive manufacturing has been based on already existing standards for traditional manufacturing methods. For composites in large scale additive manufacturing there is a research gap in bond strength and fracture toughness for a single layer interface. By using Double cantilever beam Mode I, this thesis manuscript validates testing parameters and protocols to describe the intricacies of ABS matrix 20 wt.% carbon filled composite, specifically on the layer-to-layer interface. Studies suggest that fracture toughness is sensitive to process parameters, like deflection speed and sharpened crack tip at the layer interface of BAAM 3D printed part and …

Distinct Modes Of Aged Soil Carbon Export In A Large Tropical Lake Basin Identified Using Bulk And Compound-Specific Radiocarbon Analyses Of Fluvial And Lacustrine Sediment, Wesley G. Parker, Jason M.E. Ahad, Jonathan Obrist-Farner, Benjamin Keenan, Peter M.J. Douglas

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The 14C content of sedimentary organic matter (OM) and specific organic molecules provide valuable information on the source and age of OM stored in sediments, but these data are limited for tropical fluvial and lake sediments. We analyzed 14C in bulk OM, palmitic acid (C16), and long-chain n-alkanoic acids (C24, C26, and C28), within fluvial and lake sediments in the catchment of Lake Izabal, a large tectonic lake basin in Guatemala. We combined these measurements with bulk and compound-specific δ13C measurements, as well as sediment organic carbon to nitrogen (OC:N) ratios, to understand the source and age of sedimentary OM …

Road Map Of Semiconductor Metal-Oxide-Based Sensors: A Review, Taposhree Dutta, Tanzila Noushin, Shawna Tabassum, Satyendra K. Mishra

Electrical Engineering Faculty Publications and Presentations

Identifying disease biomarkers and detecting hazardous, explosive, flammable, and polluting gases and chemicals with extremely sensitive and selective sensor devices remains a challenging and time-consuming research challenge. Due to their exceptional characteristics, semiconducting metal oxides (SMOxs) have received a lot of attention in terms of the development of various types of sensors in recent years. The key performance indicators of SMOx-based sensors are their sensitivity, selectivity, recovery time, and steady response over time. SMOx-based sensors are discussed in this review based on their different properties. Surface properties of the functional material, such as its (nano)structure, morphology, and crystallinity, greatly influence …

Analyzing The Labor Shortage In The Construction Industry And The Best Practices To Increase Worker Satisfaction, Cade Batchman

Construction Management

The construction industry is facing a significant labor shortage, which has far-reaching implications for the industry and the economy. This paper explores the causes of the shortage and the practices being implemented to address it. Economic changes, technological advancements, union/open shop dynamics, educational shifts, and the industry's image all contribute to the shortage. The economic rebound from the 1980s recession and the lack of new entrants into the field have created a demand-supply gap. Additionally, slow adoption of technology and the perception of construction work as physically demanding and risky have deterred potential workers. The decline in union membership has …

Electrosteric Control Of The Aggregation And Yielding Behavior Of Concentrated Portlandite Suspensions, Sharu Bhagavathi Kandy, Narayanan Neithalath, Mathieu Bauchy, Aditya Kumar, Edward Garboczi, Torben Gaedt, Samanvaya Srivastava, Gaurav Sant

Materials Science and Engineering Faculty Research & Creative Works

Portlandite (calcium hydroxide: CH: Ca (OH)2) suspensions aggregate spontaneously and form percolated fractal aggregate networks when dispersed in water. Consequently, the viscosity and yield stress of portlandite suspensions diverge at low particle loadings, adversely affecting their processability. Even though polycarboxylate ether (PCE)-based comb polyelectrolytes are routinely used to alter the particle dispersion state, water demand, and rheology of similar suspensions (e.g., ordinary portland cement suspensions) that feature a high pH and high ionic strength, their use to control portlandite suspension rheology has not been elucidated. This study combines adsorption isotherms and rheological measurements to elucidate the role of PCE composition …

Silicon Carbide-Based Dna Sensing Technologies, Abdulla Al Mamun, Mason Mcgarrity, Jong Hoon Kim, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

DNA sensing is critical in various applications such as the early diagnosis of diseases and the investigation of forensic evidence, food processing, agriculture, environmental protection, etc. As a wide-bandgap semiconductor with excellent chemical, physical, electrical, and biocompatible properties, silicon carbide (SiC) is a promising material for DNA sensors. In recent years, a variety of SiC-based DNA-sensing technologies have been reported, such as nanoparticles and quantum dots, nanowires, nanopillars, and nanowire-based field-effect-transistors, etc. This article aims to provide a review of SiC-based DNA sensing technologies, their functions, and testing results.

Measurement Of Vapour Pressure, Miscibility And Thermal Conductivity For Binary And Ternary Refrigerant Lubricant Mixtures In The Context Of Heat Pump Tumble Dryers, Katharina Stockel, Ramona Nosbers, Riley Barta, Christiane Thomas

School of Mechanical Engineering Faculty Publications

Household appliances need to be both efficient and cost-effective. As a result, electrically driven tumble dryers were converted to heat pump driven ones several years ago in order to comply with energy directives, in this case in Germany. In order to increase the efficiency of heat pumps of different performance classes, the use of zeotropic refrigerant mixtures can be useful, since the temperature glide during the phase change of the refrigerant mixture can be adapted to the temperature gradients of the secondary fluids. In order to take advantage of this unique property, a refrigerant mixture selection was carried out by …

Investigation Of Possible Inflammatory Response After Ultrasound And Microbubble Procedure In The Spinal Cord., Jenna Wilkerson

Electronic Theses and Dissertations

The purpose of this experiment is to explore the inflammatory effects of focused ultrasound paired with intravenously delivered microbubbles when used in the lumbar spinal cord. There are currently very few pharmaceuticals that can successfully enter the blood spinal cord barrier (BSCB). This technique used at the lumbar enlargement might allow targeted treatment of pathologies involving the spinal cord.

To test the possible inflammatory response of this technique, an animal experiment was performed. 15 animals were given a T12 laminectomy and allowed to fully recover. Once recovered, all animals received FUS+MB at L2 and were euthanized in groups of five …

Development And Application Of A Microfluidic Platform For Quantifying Intra-Tumoral Compressive Stress., Zachary P. Fowler

Electronic Theses and Dissertations

Cancer progression is linked to the emergence of aberrant mechanical signaling in the tumor microenvironment. Modulation of extrinsic signals, such as ECM stiffness and composition, have been thoroughly explored. However, the development of solid stresses within the tumor remains poorly understood. To address this, we have developed a microfluidic platform that generates deformable alginate microbeads that allow for the quantification of compressive stresses generated within a growing glioblastoma (GBM) tumorsphere. PDMS microfluidic devices were fabricated via SU-8 mold with channels ranging from 10µm-40µm in diameter. Fluorescently labeled sodium alginate underwent a cross-linking reaction within the device to generate monodisperse beads …

Addition Of Process Control Experiment To Unit Operations Ii Laboratory., Bradley Esselman

Electronic Theses and Dissertations

Process control is an essential aspect of manufacturing, contributing to improved process safety, efficiency, product consistency, and energy optimization. Chemical engineers are often responsible for ensuring the safe, efficient, and cost-effective operation of industrial processes, and process control plays a pivotal role in accomplishing this.

Chemical engineering students at the University of Louisville complete the course, Elements of Process Control, during the second semester of their fourth year. This lecture-based course offers limited hands-on, practical experience. To supplement the lack of hands-on experience in the classroom, a new process control experiment was designed and implemented into the Unit Operations …

Design And Evaluation Of A Multi-Functional Surgical Device For Microgravity Surgeries., Sienna Shacklette

Electronic Theses and Dissertations

No abstract provided.

Performance Evaluation Of A Coupled Photovoltaic-Thermal Solar Powered Desalination Pilot System, Martin Chavarin

Open Access Theses & Dissertations

A pilot scale coupled photovoltaic-thermal solar powered desalination system was evaluated at the Brackish Groundwater National Desalination Research Facility (BGNDRF). The pilot system consisted of a 3-kW photovoltaic-thermal (PVT) solar panel array and a 2.3 kW photovoltaic (PV) array coupled with a 4 gal/min single-stage 4 membrane reverse osmosis (RO) desalination system. A heat exchange system was in place to provide simultaneous cooling for the PVT system and heating to the RO system feed water. This system was evaluated with three objectives in mind. The first objective was to identify whether cooling of the PVT panels resulted in a significant …

A Novel Approach For Defect Detection Of Wind Turbine Blade Using Virtual Reality And Deep Learning, Md Fazle Rabbi

Open Access Theses & Dissertations

Wind turbines are subjected to continuous rotational stresses and unusual external forces such as storms, lightning, strikes by flying objects, etc., which may cause defects in turbine blades. Hence, it requires a periodical inspection to ensure proper functionality and avoid catastrophic failure. The task of inspection is challenging due to the remote location and inconvenient reachability by human inspection. Researchers used images with cropped defects from the wind turbine in the literature. They neglected possible background biases, which may hinder real-time and autonomous defect detection using aerial vehicles such as drones or others. To overcome such challenges, in this paper, …

Electrochemical Approaches To Life-Support Resources In Space Missions And Nuclear Technologies: Hydrogen Peroxide And Uranium Films, Armando Manuel Pena-Duarte

Open Access Theses & Dissertations

Space race has developed several technological advances that have achieved and continue to achieve the success of space missions in the aerospace timeline. Currently, the number of space technical and scientific innovations is still growing––demanding new materials and developments for extreme performing applications of fuel cells, batteries, supercapacitors, and systems of nuclear energy. Space missions require life-support solutions, auto-sustainable closed-loop living environments, cleaning and sanitizing solutions against pathogens, and safe nuclear-based resources of energy––with fissile materials with well-controlled dimensions within the core fuel elements. Likewise, to guarantee safety conditions, reduce costs, and facilitate operational logistics, space missions must reduce their …

The Genetic And Non-Genetic Factors For Impulsivity, Erick Benjamin Saldes

Open Access Theses & Dissertations

Inhibitory control is an executive function suppressing inappropriate actions or thoughts and inhibitory control dysfunction leads to impulsivity. Impulsivity is associated with wide-ranging brain disorders including attention deficit hyperactivity disorder, autism spectrum disorder, substance use disorder, and dementia. The genetic and non-genetic factors contributing to impulsivity are poorly understood. This dissertation aims to begin closing this knowledge gap by identifying the genetic and non-genetic factors for impulsivity and the underlying mechanism in the model organism Drosophila melanogaster. For this task, we developed a new Go/No-Go test, which measures the fly's ability to suppress movements in situations that can endanger its …

Effect Of Heat Treatment On The Mechanical And Corrosion Properties Of The Cocrnifeal Heas, Ahmed Korra

Masters Theses and Doctoral Dissertations

High entropy alloys (HEAs) are a relatively new class of metallic materials that have shown great potential for use in extreme environments, such as high temperatures and corrosive conditions. Among the different types of HEAs, CoCrNiFeAl HEAs are potential materials for a wide range of applications, including aerospace, biomedical, and energy storage. This work focused on the effects of heat treatment temperatures from 800 °C to 1100 °C on the microstructure and mechanical properties of these alloys, as well as their electrochemical corrosion behavior. A thermodynamic model was implemented to predict the performance of the material. The results of this …

Integrating Human Psychology Into Car-Following Models For Accurate Response Prediction: A Realistic Approach, Faiza Khan

Masters Theses and Doctoral Dissertations

Car-following models traditionally focus on vehicle kinematics or dynamics parameters without considering human psychology. However, recent research has attempted to incorporate psychology into car-following models. Despite these efforts, there are limitations in understanding the psychological triggers that influence individual drivers' responses. To address this gap, we propose a new car-following model based on the Theory of Planned Behavior (TPB), which incorporates a human element by utilizing concepts of psychology. To gather the data pertaining to human input a questionnaire was carefully developed utilizing the Theory of Planned Behavior. Data collection and analysis were done through a survey using google forms. …

Performance Improvements Of Hot Mix Asphalt Concrete Using Carbon-Based Fillers, Leonardo A. Ortega Ruiz

Theses and Dissertations

To further advance the state of the art on the performance improvements of hot mix asphalt concrete, this paper investigates the improvements to cracking damage of hot mix asphalt concrete by the addition of carbon-based fillers. There have been various studies dedicated to measuring the strength performance of asphalt mixtures modified with non-traditional fillers, but many of the current studies seem to have varying success with their results or have results that are not statistically significant. In this research, carbon black and F-516 graphite in various percentages were added into asphalt mixtures as a replacement of the traditionally used hydrated …

Simple Mechanically Reconfigurable Patch Antennas, Luis Alonso Hernandez Galvan

Theses and Dissertations

Reconfigurable antennas form an active subdivision of antenna and communications research primarily targeted at achieving reconfigurability in the RF, microwave, and millimeter-wave frequency regimes. Mechanical, all-electronic, material based, and optical methods are the most common approaches to achieve reconfigurability. Each method can overlap to create new and innovative approaches to enable device tunability. The sub-class of reconfigurable antennas are antennas that dynamically achieve an adaptable transformation of their frequency, radiation-pattern, polarization, and/or bandwidth characteristics to enable multiple dynamic functionalities.

In this thesis, we designed new rectangular and triangular microstrip patch array antennas operating in the 5G midband at 5GHz. These …

Design And Implementation Of A Load Sensor In A Bearing Adapter Assembly For Freight Railcar Applications, Prince E. Mensah

Theses and Dissertations

The U.S. freight rail network, which covers approximately 140,000 route miles, is commonly regarded as the largest, safest, and most economical freight system in the world. It generates more than 167,000 jobs nationwide and has additional advantages over other modes of transportation, such as lower costs for logistics, public infrastructure upkeep, and decreases in traffic congestion, highway deaths, fuel consumption, and greenhouse gas emissions. Knowing the exact weight of cargo hauled by freight railcars can help avoid exceeding the loading thresholds set by the Association of American Railroads (AAR). Moreover, knowing the exact load applied to each bearing on the …

Vibration-Based Machine Learning Models For Condition Monitoring Of Railroad Rolling Stock, Sergio M. Martinez

Theses and Dissertations

One of the primary causes of rail rolling stock derailments is attributed to bearing and wheel axle failures. The health of train bearings is primarily monitored at target locations through wayside detection systems. This practice is susceptible to bearing failure and potential derailments at points in between these wayside systems. To remedy this, the University Transportation Center for Railway Safety (UTCRS) has developed a wireless onboard monitoring system that can continuously monitor the vibration response, which directly correlates to the health of bearings. This data is used to train regression-based machine learning algorithms and long-term prediction neural networks to predict …

Two-Dimensional Nanomaterials And Nanocomposites For Sensing, Separation, And Energy Applications, Md Ashiqur Rahman

Theses and Dissertations

Two-dimension (2D) nanomaterials have gained popularity for the last few decades due to their excellent mechanical, electrical and thermal properties. These unique properties of 2D nanomaterials can be exploited in various applications specially in sensor, energy, and separation devices. In this study, the sensing and energy generation performance of PVDF/PAni fiber mat systems made by the forcespinning method with and without graphene coating. The graphene-coated nanocomposites show an average output voltage of 75 mV (peak-to-peak) which is 300% higher compared to bare fiber mats and an output current of 24 mA (peak-to-peak) by gentle finger pressing. Moreover, the graphene-coated PVDF/PAni …

Developing Control System For Manufacturing Processes, Md Shahriar Forhad

Theses and Dissertations

Process control has been a critical component in today's manufacturing industry. Industrialists nowadays want reliable control to assure precision manufacturing. Modern control systems must be more dynamic, so that any needed modifications may be made quickly to accomplish the desired product change. For innovative research and development, system customization is critical to ensure freedom for experimental works. In addition, full control of manufacturing systems is necessary to realize and implement Industry 4.0. Often, it is difficult to achieve such control due to limited access to proprietary equipment. To this end, this thesis focuses on developing a custom control platform for …

Robust And Uncertainty-Aware Software Vulnerability Detection Using Bayesian Recurrent Neural Networks, Orune Aminul

Theses and Dissertations

Software systems are prone to code defects or vulnerabilities, resulting in several cyberattacks such as hacking, identity breach and information leakage leading to system failure. Vulnerabilities in software systems have severe societal implications, including threats to public safety, financial damage, and even risks to national security. Identifying and mitigating software vulnerabilities is critical to protect organizations and societies from potential threats. Machine learning algorithms have been employed to detect and classify potential vulnerabilities in software source code automatically. However, these algorithms are not robust to noise or malicious attacks and cannot quantify uncertainty in the model’s output. Quantifying uncertainty in …

Phosphatase And Pseudo-Phosphatase Functions Of Phosphatase Of Regenerating Liver 3 (Prl-3) Are Insensitive To Divalent Metals In Vitro, Jeffery T. Jolly, Ty C. Cheatham, Jessica S. Blackburn

Markey Cancer Center Faculty Publications

Phosphatase of regenerating liver 3 (PRL-3) is associated with cancer metastasis and has been shown to interact with the cyclin and CBS domain divalent metal cation transport mediator (CNNM) family of proteins to regulate the intracellular concentration of magnesium and other divalent metals. Despite PRL-3’s importance in cancer, factors that regulate PRL-3’s phosphatase activity and its interactions with CNNM proteins remain unknown. Here, we show that divalent metal ions, including magnesium, calcium, and manganese, have no impact on PRL-3’s structure, stability, phosphatase activity, or CNNM binding capacity, indicating that PRL-3 does not act as a metal sensor, despite its interaction …