Engineering Commons^™

Assessment Of Light Weight Deflectometer For Low Volume Roads Experiencing Rapidly Increased Traffic Levels, Margarita Ordaz

Theses and Dissertations

When evaluating low volume roads (LVRs), structural capacity emphasis is minimal since deterioration typically results from environmental factors. However, in cases where LVR’s experience rapidly increased traffic loading, structural condition becomes important. The research objective was to determine whether the Light Weight Deflectometer (LWD) can be used as a structural evaluation tool for LVRs in the aforementioned conditions. This study explored the capability of LWD equipment in evaluating major factors that influence flexible pavement structural capacity: load induced deterioration, soil moisture, and asphalt temperature. Falling Weight Deflectometer (FWD) and LWD tests were performed to measure pavement structural condition. LWD was …

A New Saturation-Based Framework For Compaction Quality Control, Kevin Clark Miller

Theses and Dissertations

Field compaction control is arguably the most common yet critical quality control procedure in geotechnical engineering. Since the early 1930s, the systematic process for performing quality control of compacted soils has often been performed by measuring the in-place dry unit weight (or density) and as-compacted soil moisture content after placement in a fill. However, the current practice overlooks several facts resulting from comparing soil prepared and compacted in the laboratory to soils placed and compacted in the field. These issues include comparing the compaction energy in the lab versus what is applied in the field, and the behavior of saturated …

Exploring Bistatic Scattering Modeling For Land Surface Applications Using Radio Spectrum Recycling In The Signal Of Opportunity Coherent Bistatic Simulator, Dylan R. Boyd

Theses and Dissertations

The potential for high spatio-temporal resolution microwave measurements has urged the adoption of the signals of opportunity (SoOp) passive radar technique for use in remote sensing. Recent trends in particular target highly complex remote sensing problems such as root-zone soil moisture and snow water equivalent. This dissertation explores the continued open-sourcing of the SoOp coherent bistatic scattering model (SCoBi) and its use in soil moisture sensing applications. Starting from ground-based applications, the feasibility of root-zone soil moisture remote sensing is assessed using available SoOp resources below L-band. A modularized, spaceborne model is then developed to simulate land-surface scattering and delay-Doppler …

Ai-Enabled Modeling And Monitoring Of Data-Rich Advanced Manufacturing Systems, Abdullah Al Mamun

Theses and Dissertations

The infrastructure of cyber-physical systems (CPS) is based on a meta-concept of cybermanufacturing systems (CMS) that synchronizes the Industrial Internet of Things (IIoTs), Cloud Computing, Industrial Control Systems (ICSs), and Big Data analytics in manufacturing operations. Artificial Intelligence (AI) can be incorporated to make intelligent decisions in the day-to-day operations of CMS. Cyberattack spaces in AI-based cybermanufacturing operations pose significant challenges, including unauthorized modification of systems, loss of historical data, destructive malware, software malfunctioning, etc. However, a cybersecurity framework can be implemented to prevent unauthorized access, theft, damage, or other harmful attacks on electronic equipment, networks, and sensitive data. The …

Travel Time Prediction Using Machine Learning, Vignaan Vardhan Nampalli

Theses and Dissertations

With the rapid growth of urban populations and increasing vehicular traffic, congestion has become a major challenge for transportation systems worldwide. Accurate estimation of travel time plays a crucial role in mitigating congestion and enhancing traffic management. This research focuses on developing a novel methodology that utilizes machine learning models to estimate travel time using real-time traffic data collected through Bluetooth sensors deployed at traffic intersections. The research compares five different prediction systems for replicating travel time estimation, evaluating their performance and accuracy. The results highlight the effectiveness of the machine learning models in accurately predicting travel time. Lastly, the …

Ai Methods For Identifying Process Defects In Advanced Manufacturing With Rare Labeled Data, Ayantha Umesh Senanayaka Mudiyanselage

Theses and Dissertations

This dissertation aims to provide efficient process defect identification methods for advanced manufacturing environments using AI tools/algorithms with limited labeled data availability. Asset and equipment quality become highly sensitive in sustaining virtuous performance and safety in various manufacturing domains. Internally generated process imperfections degrade finished products' optimum performance and mechanical attributes. The evolution of big data and intelligent sensing systems leverage data-driven defect identification in advanced manufacturing environments. Widely adopted data-driven process anomaly detection methods assume that the training (source) and testing (target) data follow the same distribution and that labeled data are available in both source and target domains. …

Determining Student Attentiveness By Use Of Heart Rate Measurement Using A Wearable Device, Erik Rhodes Brown

Theses and Dissertations

Distraction from personal technology is a widely recognized problem in the modern classroom. Further, instructors have limited abilities to determine when students are waxing or waning in attentiveness. This evaluative experiment leverages the Apple Watch’s heart rate sensors to capture signs of attentiveness in participants simulating remote university lectures of differing interest levels as determined by YouTube commenters. Once captured, the heart rate data separated and analyzed to determine the effect of the lecture treatment on the participants’ heart rates. Twenty-seven students from Mississippi State University’s Electrical and Computer Engineering and Computer Science and Engineering departments elected to participate in …

Distributionally Robust Unsupervised Domain Adaptation And Its Applications In 2d And 3d Image Analysis, Yibin Wang

Theses and Dissertations

Obtaining ground-truth label information from real-world data along with uncertainty quantification can be challenging or even infeasible. In the absence of labeled data for a certain task, unsupervised domain adaptation (UDA) techniques have shown great accomplishment by learning transferable knowledge from labeled source domain data and adapting it to unlabeled target domain data, yet uncertainties are still a big concern under domain shifts. Distributionally robust learning (DRL) is emerging as a high-potential technique for building reliable learning systems that are robust to distribution shifts. In this research, a distributionally robust unsupervised domain adaptation (DRUDA) method is proposed to enhance the …

Investigation Of Cyclic Gaseous Solvent Injection For Enhanced Oil Recovery In Unconventional Formations, Samuel Asante Afari

Theses and Dissertations

Unconventional resources have been known to hold vast quantities of hydrocarbons. However, exploiting the oil and gas they hold was previously challenging due to their low permeabilities. Recent advances in horizontal well drilling and hydraulic fracturing have enabled oil and gas production from these reservoirs, leading to significant increases in energy supply to meet the growing energy demand. However, despite the relative technological success, considerable obstacles persist; oil production from unconventional wells often declines by more than 20% of their initial production rate within the first two years, leaving significant volumes of residual oil trapped in the formations. This overarching …

Aerodynamic Flow Control Using Micro Rotating Cylinders, Alejandro Daniel Carrizales

Theses and Dissertations

This research investigates the aerodynamic and flow field characteristics of a NACA 0010 airfoil equipped with rotating cylinders near the leading edge, subjected to a flow with a freestream turbulence intensity of 4.3%. The airfoil was modified to integrate five micro-DC motors positioned at 14.5% of the chord length from the leading edge. The cylinders, with dimensions of 0.75 inches in diameter and 0.5 inches in width, exposed 3mm of their length to the incoming flow. A modified leading edge with eight sinusoidal protrusions (tubercles) was employed to compare the performance of the micro-rotating cylinder airfoil with an unmodified baseline …

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 …

Application Of An Adaptive Controller On An Air-Bearing Vehicle-Manipulator System, Samuel Thomas Lovelace

Theses and Dissertations

The growing demand for on-orbit servicing and assembly as well as orbital debris capture and removal poses many engineering challenges. One primary challenge is that of position and attitude control of a spacecraft-manipulator system while performing these operations. Standard control approaches may be used for cases where the dynamics of the objects that the spacecraft-manipulator system interacts with are known are still plausible. However, there will likely be some uncertainty and lack of knowledge of the dynamic properties of orbital debris and parts required for servicing. Therefore, many have proposed the use of adaptive control schemes which can recalculate the …

Mitigate The Flood Risk At The Parking Lots At The University Of Texas Rio Grande Valley - Edinburg Campus, Mishell Carolina Mazon

Theses and Dissertations

This study focuses on the analysis of the drainage system in the parking lots of the Edinburg campus of the University of Texas Rio Grande Valley. The current project will use the rational method and modified rational method described in the Texas Department of Transportation manual to analyze and determine a solution for the current built drainage system. The primary objective of this study is to offer a practical and comprehensive solution to address the issue of this area that has flooded during heavy rainfall storm events. The proposed solution takes into consideration the building codes of the city of …

Nrc-Sim: A Node-Red Based Multi-Level, Many-Core Cache Simulator, Ezequiel Treviño

Theses and Dissertations

As computational systems become ever-more integral to daily life, so too does the importance of understanding how these complex systems work. For those unfamiliar with the underlying concepts, this can be a daunting task. In an effort to address such concerns, this paper presents a Node-RED based cache simulator that enables users to observe the effects of their desired cache configuration, with users having the ability to easily modify various parameters, such as the core count, the number of levels within the cache, and coherence protocols, among other parameters. Through the use of Node-RED, NRC-SIM allows for simplicity of use …

Machine Learning-Based Drone And Aerial Threat Detection For Increased Turret Gunner Survivability, Nikolas Koutsoubis

Theses and Dissertations

The introduction of aerial drones on the modern battlefield has transformed combat operations, posing a significant threat to ground-based military operations. Detecting drones in safety scenarios is crucial. However, modern machine learning (ML)-based object detectors struggle to detect small objects like drones. This thesis presents three main contributions: (a) data and algorithmic modifications to improve small object detection in YOLO to aid in drone detection, (b) the development of a benchmark drone detection dataset called DyViR, and (c) the implementation of explainable artificial intelligence (XAI) to ensure transparent and trustworthy decision-making. To boost the performance of small object detection, we …

Evaluating The Permeability Of Porous Aggregate Concrete Using Electrical Resistivity-Based Measurements, Ariel Miguel Mendez Aragoncillo

Theses and Dissertations

Recycled concrete aggregates (RCA) and lightweight aggregates (LWA) are popular alternative aggregates for concrete. However, due to their highly porous structure, concrete with RCA and LWA shows a different microstructure and higher permeability than conventional concrete. Thus, the existing relationships used to evaluate the permeability and, consequently, the durability of concrete are not applicable in concretes with RCA and LWA. This research examined the permeation properties of recycled aggregate concrete (RAC) and lightweight aggregate concrete (LWAC). The relationships between electrical resistivity-based measurements in RAC and LWAC and their permeation properties were determined and compared to that of normal weight aggregate …

Investigation Of The Performance Of Anti-Corrosive Coating Materials Derived From Bio-Based Feedstocks, Sarah Anne Salazar

Theses and Dissertations

Corrosion is a costly phenomenon that is largely responsible for the deterioration of various infrastructures. While there are many corrosion prevention techniques, polymeric coatings are the most cost-effective and frequently used methods for protection of metal surfaces. The most commonly employed polymeric coatings are non-renewable BPA-based epoxide resins. Common curing agents are also the derivatives of hazardous amines such as ethylene di-amine and methylene dianiline. Therefore, there is a growing demand to develop renewable and less-harmful precursors from biomass to replace rapidly depleting petrochemicals. This thesis focuses on the characterization and optimization of anti-corrosive polymeric coating formulations derived from renewable …

Comparison Of Compact Very High Frequency (Vhf) Antennas For Small Airborne Ground Penetrating Radar, Tayler Austen Livingston

Theses and Dissertations

UHF bands because more penetration can be achieved at low frequencies. Consequently, large antennas are required, which limits their use for small airborne applications. This thesis explores various GPR antenna designs for a bi-static system that are at least operational from 225 MHz to 255 MHz and suitable for small airborne applications. The 3D electromagnetic simulation software Ansys high-frequency structure simulator (HFSS) was used to simulate various sizes of strip dipole, triangular bowtie, half elliptical bowtie, and elliptical bowtie antennas. Several physical models were constructed to validate the return loss simulation results. Additionally, simulation data is included for a wire …

Heat Transfer To Rolling Or Sliding Drops On Inclined Heated Superhydrophobic Surfaces, Joseph Merkley Furner

Theses and Dissertations

This thesis examines the time resolved heat transfer to drops rolling or sliding along inclined, subcritical heated non-wetting surfaces. Results were experimentally obtained using IR imaging for a smooth hydrophobic surface and post as well as rib structured superhydrophobic surfaces of varying solid fraction (f_s = 0.06 - 0.5). Tests were performed at varying inclination angle (α = 10, 15, 20, and 25°), drop volume (12, 20, 30, and 40 μL), and surface temperature (T_w = 50, 65, and 80 °C). Rib structured superhydrophobic surfaces were explored for drops moving parallel and perpendicular to the rib structures. The findings indicate …

Nasa Weather Data Based Neural Network Grid Connected Pv System Maximum Power Point Tracking, Oluwatobiloba Mausi Johnson

Theses and Dissertations

Research and development for alternative energy sources that are cleaner, renewable, and have little to no environmental impact have been pushed by the ongoing rise in energy demand, the possibility of a decline in the use of conventional petroleum fuels, and concerns about environmental degradation. Electricity from photovoltaic (PV) systems is significantly better regarded among these alternative sources as a renewable energy source such as wind power, bioenergy, tidal energy, and hydroelectric with a wide application range because it is clean, accessible, and abundant with little to no environmental effect. However, solar energy usage is significantly impacted by the landscape, …

Radar Processing Techniques For Using The Limesdr Mini As A Short-Range Lfm Radar, Jacob Scott Stratford

Theses and Dissertations

Drone-mounted ground penetrating radar (GPR) has the capability to investigate terrain that is inaccessible or hazardous to humans. A linear frequency-modulated (LFM) radar with the potential for GPR applications is described based on the LimeSDR Mini software defined radio (SDR). Challenges of the LimeSDR Mini radar include the SDR's lack of support for transmitter-receiver synchronization and high bleedthrough leakage. These issues are overcome through corrective software processing techniques including deconvolution of the SDR's system impulse response and digital feed-through nulling. Feed-through nulling is effective at reducing bleedthrough leakage, achieving a 26 dB reduction in power. Although high noise can confound …

From Waste To Energy: The Electrochemical Reduction Of Co2 Using Recycled Nanostructured Catalysts, Ibrahim Badawy

Theses and Dissertations

The reduction of carbon dioxide (CO₂RR) using electrochemistry is a promising solution for the burgeoning global energy crisis. The overall vision of its implementation relies on renewable energy sources to power the reaction creating carbon neutral products and effectively closing the carbon cycle. Research in this field has come a long way since its inception in the mid-1900s. However, there remain significant hurdles and important considerations to overcome in order to reach full commercialization. Most electrocatalysts tested for CO₂RR have been designed solely for maximum performance while ignoring the environmental consequences if such a material were …

Microfabrication Of Silicon Carbide And Metallized Polymers Using A Femtosecond Laser, Joseph Taylor Eddy

Theses and Dissertations

Femtosecond lasers deliver a high peak concentration of optical power while maintaining low average power. With an accompanying optical setup, this power can be focused and used for high-precision fabrication of metallized polymers via ablation, creating conductive structures on a thin film. These lasers can also be harnessed in tandem with hydrofluoric acid and the two-photon absorption principle to selectively etch silicon carbide, a very durable and machining-resistant semiconductor with desirable properties. This thesis presents improvements made to the Laser-Assisted Chemical Etching (LACE) technique and the ablation system. ��, the two- photon absorption coefficient of silicon carbide, is measured and …

Analysis Of The Performance, Recertification, And Sustainability Of A Cessna 172n Modified With An O-360-A4m Powerplant, Variable Timing Electronic Ignition, And Tuned Exhaust, Kelsey Lee Kaht

Theses and Dissertations

The purpose of this thesis is to discuss the performance, modification, and recertification of the test aircraft, a Cessna 172N that has been equipped with an O-360-A4M power plant, tuned exhaust, and variable timing electronic ignition, and to compare the aircraft to a stock aircraft and other high-performance aircraft to determine the feasibility of the modifications. 65 knot, 80 knot, and 95 knot steady state climb and 2000 ft and 5000 ft level acceleration tests were performed with the test aircraft at the Melbourne Orlando International Airport. The weather was clear with calm wind, and there was only one issue …