Engineering Commons^™

Gpu-Enabled Genetic Algorithm Optimization And Path Planning Of Robotic Arm For Minimizing Energy Consumption, Yichuan Cao

Theses and Dissertations

The robotic arm represents a complicated mechanical system and advanced engineering principles in robotics, enabling precise and efficient manipulation and interaction with objects in a variety of applications, such as manufacturing, healthcare, space exploration, and other industries. In most cases, energy consumption of robotic tools has been given little consideration due to their perceived insignificance compared to the benefits they offer. However, the increasing capacity demands of factories and the expanding use of robotic arms necessitate careful evaluation and reduction of energy consumption. In this regard, given a task configuration, adjusting the arm's movement path emerges as one of the …

Leveraging Programmable Switches To Enhance The Performance Of Networks: Active And Passive Deployments, Elie Kfoury

Theses and Dissertations

The performance of networks today is drastically affected by: 1) switches equipped with large buffers, referred to as “bloated buffers”: due to the lack of programmability and traffic visibility in legacy switches, operators nowadays configure large buffers statically without considering the characteristics or dynamics of flows. Such buffers increase the delays on packets, causing the Quality of Service (QoS) of networked applications (e.g., voice over IP, web browsing) to degrade; 2) switches forwarding packets on a best-effort basis: traffic crossing a switch is heterogeneous in many ways. Mixing such traffic in a single queue without any QoS measures can drastically …

Extending The Convolution In Graph Neural Networks To Solve Materials Science And Node Classification Problems, Steph-Yves Mike Louis

Theses and Dissertations

The usage of graph to represent one's data in machine learning has grown in popularity in both academia and the industry due to its inherent benefits. With its flexible nature and immediate translation to real life observed objects, graph representation had a considerable contribution in advancing the state-of-the-art performance of machine learning in materials.

In this dissertation proposal, we discuss how machines can learn from graph encoded data and provide excellent results through graph neural networks (GNN). Notably, we focus our adaptation of graph neural networks on three tasks: predicting crystal materials properties, nullifying the negative impact of inferior graph …

Automated Fiber Placement Through Thickness Defect Stacking Optimization, Noah Christopher Swingle

Theses and Dissertations

In its 2022 commercial market outlook, Boeing forecasted an 80% increase in the global fleet through 2041 compared to 2019 pre-pandemic levels. This sharp rise in demand will drive pressure onto airframe manufacturers to ramp up production and find more efficient ways to design and manufacture airplanes. Complicating this challenge is the industry’s recent transformation from traditional metal-based airframes towards hybrid composite-metal aircraft. While composites have been used in aviation for decades, aircraft manufacturers are still struggling to design and manufacture quality parts at a high rate. Automated Fiber Placement (AFP) is one of the main manufacturing techniques used to …

Implementation Of A 3d Laser Profiler System Into A Non-Contacting Method For Rnt & Stress Measurements, Caio Neto Penna

Theses and Dissertations

Continuous welded rail (CWR) is susceptible to the development of internal forces in the rail due to thermal effects that can lead to track buckling. Railroads typically deal with the internal stresses in the rail through the inspection of the rail neutral temperature (RNT) which is the temperature at which the internal force is zero. The existing methods in the industry to measure RNT are contacting, destructive, disruptive to railroad operations, and ineffective. The proposed concept is a promising non-contacting, non-disruptive and reference-free technique to measure RNT and the stress state in the rail. The method is based on the …

Impact Of Dam Height And Grain Size Distribution On Breaching Of Non-Cohesive Dams Due To Overtopping, Heather O'Donal

Theses and Dissertations

The National Inventory of Dams reports 74,400 earthen dams in the United States in 2021, of these dams approximately 27% are considered at high or significant hazard risk, that is dam failure will cause widespread damage and loss of lives. The most frequent cause of dam failure is breaching caused by overtopping. Accurate predictions of breach evolution are thus crucial to determine flood hydrographs for the safety of communities and properties at risk. Laboratory experiments were conducted on non-cohesive, compacted embankments to understand the role of dam height and sediment grain size on breaching caused by overtopping. Dam heights varied …

Revisiting The Volumetric Swing Frequency Response Method For The Determination Of Limiting Mass Transfer Mechanisms Of N2 And O2 In Carbon Molecular Sieve 3k172, Adam Marshall Burke

Theses and Dissertations

Adsorption-based separations processes, along with the adsorbents that enable them, have benefited from a greater particular focus in recent years, following a desire to improve process energy efficiencies and cost economics. One such adsorbent, carbon molecular sieves (CMS), have likewise been a greater focus. CMS materials offer several key practical uses, such as the separation of nitrogen and oxygen, and the removal of carbon dioxide from methane process streams. In order to effectively design and implement an industrial scale process using a CMS material, the behavior of these gases on the chosen material must be known, including the limiting mass …

Developing A Vision-Based Framework For Measuring And Monitoring Water Resource Systems Using Computer Vision And Deep Learning Techniques, Seyed Mohammad Hassan Erfani

Theses and Dissertations

Increased vulnerability of water systems to extreme events and climate change is among the profound challenges facing the management of water resource systems around the world. Extreme events, including droughts, floods, and natural hazards have become more frequent and intensive, particularly in coastal regions. Floods, for instance, caused tens of billions of US dollars losses and put the lives of thousands in danger, globally. To cope with the adverse consequences of floods, a wide range of structural, non-structural, and emergency measures are studied and deployed by flood management sectors. Various flood simulation, mapping, and forecast systems have been developed to …

Digital Health Design For Improving Treatment Decisions, Akanksha Singh

Theses and Dissertations

In the age of artificial intelligence and large datasets, information retrieval by querying large databases is an impossible task for the common user due to the information overload. Recommender Systems (RS) for commercial applications like YouTube, Amazon and Netflix were designed to support users by finding items of interest based on their user profiles and various filtering techniques. Health Recommender Systems (HRS) is a category of RSs that provides immense opportunities for application across several healthcare domains and contexts including treatment decision support. Unlike RS applications that focus on analyzing consumer choices, a key differentiator for HRS applications is the …

A Systems Approach To Design And Plan Sustainable Antifragile Infrastructure Based On Aggregate Footprint And Satisfaction, Farboud Khatami

Theses and Dissertations

The concepts of robustness and sustainability in planning and design of water and energy infrastructures have been extensively explored in previous research, primarily focusing on system reliability, environmental considerations, and economic aspects. This study aims to broaden the understanding of these concepts by offering comprehensive frameworks that capture the essence of robustness and sustainability at two distinct levels.

The first level of investigation focuses on the performance of infrastructure networks during natural disasters. Traditionally, this has been addressed using reliability, resilience, and vulnerability metrics. However, these methods rely on static, deterministic, and non-stationary data, which is inadequate when dealing with …

Streamwise And Vertical Dispersal Of Tracer Stones From A Continuously Supplied Source, Amanda Grace Balkus

Theses and Dissertations

Individual movement of sediment grains is oftentimes studied with the use of tracer stones. Studies performed both in the field, in the laboratory and with numerical models involve installing a patch of stones (tracers) on the bed surface and rarely deep in the deposit. Once installed, particle displacement is monitored over time scales varying from one flood to several years. These studies are useful, for example, to study bedload transport dynamics, understand contaminant fate and transport as well as to identify and define stream restoration practices (e.g. quality of fish habitat). Here we use a vertically continuous model to study …

Liquid Cooling System For A High Power, Medium Frequency, And Medium Voltage Isolated Power Converter, Hooman Taghavi

Theses and Dissertations

Controlling and transforming electrical power from one form into another is the Primary function of the power electronics systems that are employed today. These systems have a wide variety of applications and are utilized in things like industrial automation, electric cars, consumer electronics, and renewable energy systems, among other things. The functioning of power electronics systems results in the production of a substantial quantity of heat, despite the fact that these systems are very dependable and efficient. This heat must be dispersed to preserve system performance and avoid component damage. By ensuring that the working temperature of the components stays …

Predicting Material Structures And Properties Using Deep Learning And Machine Learning Algorithms, Yuqi Song

Theses and Dissertations

Discovering new materials and understanding their crystal structures and chemical properties are critical tasks in the material sciences. Although computational methodologies such as Density Functional Theory (DFT), provide a convenient means for calculating certain properties of materials or predicting crystal structures when combined with search algorithms, DFT is computationally too demanding for structure prediction and property calculation for most material families, especially for those materials with a large number of atoms. This dissertation aims to address this limitation by developing novel deep learning and machine learning algorithms for effective prediction of material crystal structures and properties. Our data-driven machine learning …

Analysis, Measurement, And Modeling Of Millimeter Wave Channels For Aviation Applications, Zeenat Afroze

Theses and Dissertations

Millimeter wave (mmWave) communication systems can employ a large amount of spectrum, and can consequently offer large data rates, e.g., multi-Gigabits-per-second. This technology can be used in many sectors: aviation, vehicles, public transportation, robotics, autonomous factories, etc. Yet mmWave communication systems suffer from some propagation challenges, including large free space path loss (PL), large penetration loss, and large diffraction loss. Hence, it is vital to quantify these and other channel effects to ensure link reliability. Most mmWave systems will employ directional antennas to enable acceptable link distances. In many settings this will require directional receiver antennas to rotate in azimuth …

Development Of Atomistic Machine Learning Approaches For Thermal Properties Of Multi-Component Solids And Liquids, Alejandro David Rodriguez

Theses and Dissertations

Currently, heat transfer in many industries is the limiting factor for innovation, especially in the energy sector. For example, maximizing thermal conductivity of ceramic coatings in power plant devices improves the overall electrical to thermal energy ratio, whereas minimizing thermal conductivity is required for desirable heat-to-electricity conversion in thermoelectric devices. As such, rapid discovery of new materials with extreme thermal conductivity values is quintessential for the near-future deployment of current and developing energy applications.

The vibrational properties of crystalline materials are essential for their ability to conduct heat. Fundamentally, the restorative atomic forces of displaced atoms are sufficient to represent …

Conceptual Design And Preliminary Safety Analysis Of A Proposed Nuclear Microreactor For Mobile Application, A. S. M. Fakhrul Islam

Theses and Dissertations

Conceptual design and preliminary safety analysis of a proposed helium-cooled Micro Nuclear reactor In ONe megawatt (MINION) thermal output is done through three-dimensional computational analysis. Compared with the conventional high temperature gas-cooled reactors (HTGR) that use tri-structural or bi-structural isotropic (TRISO or BISO) fuel particles, MINION uses traditional clad fuel pellets. This greatly simplifies the core design and allows for a substantially more compact design thanks to the fuel’s signif-icantly higher U-235 atom density. Uranium carbide (UC) enriched up to 19.75% in U-235 is used as fuel. In the power-flattened design, U-235 enrichment varies radially between 19.75% and 10.5% in …

Magnetic Softness Tuned Superparamagnetic Nanoparticles For Highly Efficient Cancer Theranostics, Jie Wang

Theses and Dissertations

Magnetic resonance imaging (MRI)-guided magnetic nanofluid hyperthermia (MNFH) using iron oxide based superparamagnetic nanoparticles (SPNPs) has recently attracted considerable attention as a treatment modality for cancer theranostics, because MRI-guided MNFH can allow for diagnosis, therapeutics, and prognosis simultaneously using the same administrated magnetic nanofluid agent. However, several primary limiting factors: (1) insufficient AC magnetic heating induction (specific loss power/intrinsic loss power, SLP/ILP) at the biologically safe and physically tolerable range of AC magnetic field (H_AC,safe: f_appl × H_appl < 3.0 ~ 5.0×10⁹ A·m^-1·s^-1), (2) low _r2- relaxivity directly related to the low resolution of …

Spin Mediated Topological Black Hole In Acoustic Metamaterials Near Dirac-Like Cone Frequencies., Mustahseen Mobashwer Indaleeb

Theses and Dissertations

A unique bulk-boundary distinction and acoustic topological phenomena is discovered and explained in this dissertation. The overall objective was to discover the hidden physics, dynamic and mechanics of acoustic wave behavior that causes the formation of extremely rare ‘Topologically protected Black Hole’ (TBH) in acoustic microarchitecture metamaterials. This behavior is immensely valuable for numerous mechanical and civil engineering applications where acoustic insulators are required to create sound-free or vibration-free exterior surfaces. On the other hand, to contain the energy within the structure, for impact mitigation and energy absorption in vehicles, space crafts, aircrafts, and civil infrastructures such materials will be …

Leveraging Automated Fiber Placement Computer Aided Process Planning Framework For Defect Validation And Dynamic Layup Strategies, Joshua Allen Halbritter

Theses and Dissertations

Process planning represents an essential stage of the Automated Fiber Placement (AFP) workflow. It develops useful and efficient machine processes based upon the working material, composite design, and manufacturing resources. The current state of process planning requires a high degree of interaction from the process planner and could greatly benefit from increased automation. Therefore, a list of key steps and functions are created to identify the more difficult and time-consuming phases of process planning. Additionally, a set of metrics must exist by which to evaluate the effectiveness of the manufactured laminate from the machine code created during the Process Planning …

Experimental Observation Of Sphere Symmetric Isolated Single Droplet Combustion In A Converging Channel, Mason Carrington Williams

Theses and Dissertations

Spherically symmetric isolated single droplet combustion has been observed mainly in microgravity conditions. This study sought to determine if spherically symmetric combustion can be produced in a lab-scale experiment using flow acceleration to counteract the effects of buoyancy. The experiment was conducted in a converging channel that decreased in width along its length to accelerate the flow and limit the formation of a boundary layer. The rate at which the area decreased was governed by the initial velocity condition set at the channel inlet.

The droplets were generated using a piezoelectric actuator which forced fuel out of an injector with …

Nondestructive Damage Detection And Stress Corrosion Crack Mitigation In Stainless Steel Plates, Andrew Philip Campbell

Theses and Dissertations

The ability to inspect and detect damage within a structure without permanent damage has broad appeal in a range of engineering applications from aerospace structures to nuclear facilities. Non-destructive evaluation (NDE) using guided ultrasonic Lamb waves has growing potential and popularity in these fields. Lamb waves are known for being sensitive to material properties and various defects across the thickness such as cracks in metallic structures and delamination or debonding in composite structures. Research has also been done on the development of fully non-contact system that generates and detects Lamb waves, particularly focused on the use of pulsed laser for …

Comprehensive Process Planning Optimization Framework For Automated Fiber Placement, Alex Ryan Brasington

Theses and Dissertations

Advanced composite materials came about in 1966 and have since been widely used due to the possibility of superior structural performance while also achieving weight reductions. Such opportunities have led to composite materials being used to fabricate complex components, often in the aerospace sector. Most components, especially in aviation, are on a large scale and are outside the capabilities of traditional composite manufacturing techniques. Traditional manufacturing methods are also labor intensive, time consuming, have a high level of material scrap, and are prone to human error. This has led to the need for innovative manufacturing solutions to withstand the ever-increasing …

Characterization Of The Spatial And Temporal Dynamics Of Floodplain Surface-Water Circulation, Shailesh Cyriel Van Der Steeg

Theses and Dissertations

Floodplains are spatially complex landscapes with a variety of surface features and landforms. These low-relief, low-gradient landscapes may contain extensive networks of well-defined channels and topographically connected depressions, and in some cases, the channels originate as cuts across levees or banks of the main river, referred to as through-bank channels. Corresponding complex patterns of inundation and flow have been detected through remote sensing and in field observations. The complex floodplain flows in response to the passing of flood waves is, however, poorly quantified. This work aims to increase fundamental understanding of floodplain flows and to highlight controls on floodplain wetting, …

Novel Structures And Thin Film Techniques For Reconfigurable Rf Technologies With Improved Signal Integrity, Jinqun Ge

Theses and Dissertations

Over the past several decades, wireless communications have been tremendously developed with multiple frequency bands, standards, and functions to provide more convenient communication services. Nowadays, commercial wireless devices, especially customer premises equipment, are required for smaller size, higher integration, and higher data rates to meet the ever-increasing demands of communications. The transceiver front ends inside these devices need to provide high-speed and high-quality communication services without a substantial increase in cost and size. Hence, the primary objective of this research is to develop a few miniaturized, multifunctional, and reconfigurable RF technologies and to provide several signal integrity and heat dissipation …

Detecting Physiological Concentrations Of Alzheimer’S Associated Amyloid-Β Protein Utilizing A Cell-Based Response, Brittany Elizabeth Watson

Theses and Dissertations

Alzheimer’s disease (AD) is characterized symptoms of cognitive impairment resulting from blood-brain barrier (BBB) breakdown and neuronal cell death. AD is associated with aggregated amyloid-β (Aβ) plaques deposited around brain vasculature and within the brain. Changes in the brain occur up to 20 years before symptoms arise; however, there is currently no pre-symptomatic detection method available for AD. An intact BBB requires tight junction proteins (TJs) that render relatively high transendothelial electrical resistance (TEER). AD-associated breakdown of the BBB correlates with vascular Aβ deposition, suggesting that aggregated, pathological Aβ can modulate TEER. We explore leveraging this cellular response for early …

Role Of Sediment Type, Concentration, And Salinity On Clay Flocs, Ryan Michael Johnson

Theses and Dissertations

Experiments were performed to study floc formation in water bodies. In particular, the study aimed to systematically identify effects of water depth, time, salinity, initial clay concentration, and clay type on floc formation and settling. Three sediment types were chosen for this research are Three sediment types were chosen for this research: silica powder, with particle sizes comparable to clay flocs, kaolin clay and bentonite clay. Silica was chosen as a control because it did not form flocs. Kaolin represented low activity clay; bentonite was chosen as the high activity clay. Experiments lasted up to 48 hours. Graduated cylinders were …

Mathematical Analysis Of Electrochemical Systems, Shiv Krishna Reddy Madi Reddy

Theses and Dissertations

A solid electrolyte interphase (SEI) growth model is developed in a mixed modethat contains solvent diffusion through the SEI layer and corresponding solvent reduction kinetics at the SEI/electrode interface. The governing equations are solved by the Landau transformation, which makes the moving layer fixed to predict the open circuit potential, SEI layer thickness, and capacity loss. The estimated parameters fitted with experimental data from the literature are computed using COMSOL and MATLAB. Results show that the mixed mode model predicts lower capacity loss and thinner SEI layer due to its growth under open circuit conditions than previously reported by others. …

Vision Controlled Autonomous Stakebot For Driving Stakes And Its Digital-Twin, Corey Lee Leydig

Theses and Dissertations

In this thesis a novel vision-based AI driven autonomous ‘StakeBot’ is proposed to serve the agricultural 4.0 industries of the future. In recent years supply, demand and production of vegetables that are harvested from plants with weak stems like bell pepper, tomato, eggplant has been significantly up by several fold. With growing demand and new green-house establishments across the country production of vegetables will require a tremendous number of labors which will be hard to supply soon. To overcome the issues in addition to the labor shortages, automation through robotics will be the only viable solution. Plants like bell peppers …

New Perspectives And Insights Into Direct Epoxidation Of C3H6 Using O2 And Ag Based Catalysts And Measurement Of Active Ag Site Concentration Of Promoted Ag Catalyst For C2H4 Epoxidation By H2 Pulse Titration Over Oxygen Pre-Covered Surface, Md Masudur Rahman

Theses and Dissertations

Direct epoxidation of C₃H₆ using molecular O₂ and Ag catalysts to produce propylene oxide (PO) selectively is a long-sought goal in the field of heterogeneous catalysis. In the early 1990’s Scientists at ARCO reported promising results of 58 – 59% selectivity to PO at 3.2% conversion of C₃H₆ over an unusual composition of 54.0 wt% Ag, 2.0 wt% K⁺, 0.5 wt% Mo and balance CaCO₃. Feed additives of ethyl chloride (EtCl), nitric oxide (NO) and CO₂ were stated necessary to achieve the claimed high PO selectivities. The roles …

Speckle Development And Application In Uav-Based Digital Image Correlation For Transportation Infrastructure Monitoring And Assessment, Taylor Wyatt

Theses and Dissertations

A critical aspect of civil infrastructure is structural health monitoring, of which digital image correlation (DIC) has been proven to be an effective and appropriate method. There is sufficient literature on the use of stationary DIC, but an unexplored aspect is DIC-equipped unmanned aircraft systems. It has been verified in University of South Carolina labs but has not been proved in a field environment. One of the challenges of field implementation is large scale speckle application. This work focusses on identifying and addressing challenges in bringing UAV-DIC technology from the lab to the field. This includes the development of optimized …