Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 12361 - 12390 of 196048

Full-Text Articles in Engineering

Evaluation Of Polymer Coated Fabrics Subjected To Various Multiaxial Stress States, Shane Marx Jan 2025

Evaluation Of Polymer Coated Fabrics Subjected To Various Multiaxial Stress States, Shane Marx

Open Access Master's Theses

All CUI (Controlled Unclassified Information) is U.S. government property and has been removed from this thesis.


Tracking Control Of A String Actuated Soft Trunk Robot Using State-Space Modeling, Jacob Trivisonno Jan 2025

Tracking Control Of A String Actuated Soft Trunk Robot Using State-Space Modeling, Jacob Trivisonno

Open Access Master's Theses

Soft robots, primarily composed of compliant materials, exhibit highly complex and nonlinear dynamics, making precise control a significant challenge. Traditional control methods often struggle with these complexities, requiring more advanced and data-driven methods. In our previous work, “Automatic Control of a Soft Trunk Robot Actuated by Strings” [1], a proportional controller was developed to drive the steady-state tracking error to zero. While this method was effective, it required time-consuming manual tuning and was not easily adaptable to physical modifications of the robot.

To address these limitations, this research implements gain-scheduled feedback control with state-space models calculated through a multiple linear …


Near-Field Interactions Of A Bubble Screen And Underwater Explosion (Undex), Ian Millspaugh Jan 2025

Near-Field Interactions Of A Bubble Screen And Underwater Explosion (Undex), Ian Millspaugh

Open Access Master's Theses

CUI content has been removed.


Modeling The Noise Attenuation Effects Of Bubble Curtains At Coastal Virginia Offshore Wind Installation, Gavin Dies Jan 2025

Modeling The Noise Attenuation Effects Of Bubble Curtains At Coastal Virginia Offshore Wind Installation, Gavin Dies

Open Access Master's Theses

The Coastal Virginia Offshore Wind (CVOW) pilot project consists of two turbines roughly 40 km off the coast of Virginia Beach, Virginia. Water- and seabed-borne acoustic and seismic signals from impact pile driving at CVOW were recorded during the installation of these turbines in May 2020. In-water pressure signals were measured using various methods at multiple ranges. The water depth at the wind turbines and the measurement devices was approximately 26 m. During installation, one of the monopiles utilized a double bubble curtain, while the other monopile did not. This arrangement has allowed for an analysis of the bubble curtain’s …


Comparative Study Of Physiological Signals Between The Embraceplus And The Shimmer3 Gsr+, Cassidy Considine Jan 2025

Comparative Study Of Physiological Signals Between The Embraceplus And The Shimmer3 Gsr+, Cassidy Considine

Open Access Master's Theses

Understanding team dynamics and their physiological impact is essential across high-stakes industries such as healthcare, aviation, and defense. In stressful environments, optimizing team performance requires not only assessing communication but also monitoring physiological indicators of stress. Electrodermal activity (EDA) and heart rate variability (HRV) are commonly used to capture autonomic responses, offering insight into emotional arousal and cardiovascular regulation.

This pilot study compares a commercial wearable device, the EmbracePlus, with a research-grade device, the Shimmer3 GSR+, to evaluate differences in physiological signal acquisition. Twelve participants completed a five-phase experimental protocol while wearing both devices simultaneously on the non-dominant wrist/forearm. EDA …


Biaxial Mechanical Behavior And Thermal Modeling Of Ductile Metals, Spencer P. Smith Jan 2025

Biaxial Mechanical Behavior And Thermal Modeling Of Ductile Metals, Spencer P. Smith

Open Access Master's Theses

All CUI (Controlled Unclassified Information) is U.S. government property and has been removed from this thesis.


Optical-Link-Aware Online Waypoint Planner For Asv-Auv Systems, Ansel R. Austin Jan 2025

Optical-Link-Aware Online Waypoint Planner For Asv-Auv Systems, Ansel R. Austin

Open Access Master's Theses

The growing demand for ocean mapping and survey missions has increased interest in reliable AUV-ASV platforms. In such systems, reliable communication between the AUV and ASV is critical for monitoring the AUV's status and offloading large data products such as multi-beam sonar point clouds. While the range of acoustic telemetry can span several kilometers, its bandwidth is inadequate for transmitting high-volume data streams (such as images and point clouds). Underwater optical communication modems, in contrast, provide a relatively high bandwidth but are hindered by rapid attenuation in turbid water and a narrow field of view. This thesis introduces an online, …


Investigation Of Subsurface Thermal Radiation Phenomena In Fibrous Thermal Protection Systems, Colby L. Gore Jan 2025

Investigation Of Subsurface Thermal Radiation Phenomena In Fibrous Thermal Protection Systems, Colby L. Gore

Theses and Dissertations--Science, Technology, Engineering, and Mathematics (STEM) Education

Atmospheric re-entry induces intense thermal stress upon vehicles through a high-enthalpy boundary layer that encompasses the craft. To protect these vehicles, numerous insulative methods, known as thermal protection systems (TPS), are deployed to protect the craft during re-entry. The TPS materials insulate the craft from intense thermal transmission that would terminate a mission. In hypersonic environments, vast temperature gradients exist, enforcing the exponential effect of thermal radiation. However, TPS materials are commonly low-density fibrous materials that allow for the potential to be penetrated by thermal radiation. A series of arc-jet tests was completed to replicate enhanced radiative conditions in a …


Innovative Biomechanical And Engineering-Based Assessments Of Hip Mechanics In Individuals With Hip-Related Pain, Holly M. Stanze Jan 2025

Innovative Biomechanical And Engineering-Based Assessments Of Hip Mechanics In Individuals With Hip-Related Pain, Holly M. Stanze

Theses and Dissertations--Kinesiology and Health Promotion

Individuals with hip-related pain exhibit altered movement patterns, and worse fear of movement (kinesiophobia), compared to asymptomatic controls. Exacerbation of hip pain during movement and the role of hip symptom duration may help further our understanding of specific movement patterns that are associated with hip-related pain. A better understanding of the potential connections between hip-related symptom duration, kinesiophobia, hip pain during movement, and lower limb mechanics in those with hip-related pain may allow for more efficient referrals to clinicians and lead to more effective rehabilitation. In addition, the impact of hip-related pain on intra-articular hip loading patterns is not well …


Magnetic Heating Efficiency Of Magnetite Nanoparticles: Dependence On Size And Alternating Magnetic Field, Sarah E. Kubican Jan 2025

Magnetic Heating Efficiency Of Magnetite Nanoparticles: Dependence On Size And Alternating Magnetic Field, Sarah E. Kubican

Theses and Dissertations--Biomedical Engineering

Magnetic heating mediated by magnetic iron oxide nanoparticles (MION) has several clinical applications including cancer thermal therapy, tissue thawing for organ preservation, and magnetogenetics. However, current models of magnetic heating, including the widely used linear response theory, inadequately predict MION heating efficiency. An experimental study covering alternating magnetic field (AMF) strengths and frequencies ranging from 3.98 – 27.85 kA/m and 103.6 – 984.1 kHz, respectively, with a range of MION core diameters 9.5- 30.3 nm was conducted to elucidate the relationships between these AMF parameters and MION sizes and the resulting heating efficiencies. Heating efficiency was found to increase approximately …


Pathogen Surveillance Of Viruses And Antimicrobial Resistance Through Wastewater Based Epidemiology, William Strike Jan 2025

Pathogen Surveillance Of Viruses And Antimicrobial Resistance Through Wastewater Based Epidemiology, William Strike

Theses and Dissertations--Biomedical Engineering

Pandemic surveillance is a cornerstone in public health safety, as it enables identification of pathogens circulating within a community before they become widespread outbreaks. Wastewater based epidemiology has blossomed in recent years due to its success in the SARS-CoV-2 pandemic, but this form of public health surveillance has a global equity problem. A large majority of the wastewater-based surveillance work has been done in large metropolitan cities with access to advanced testing infrastructure, which poses a challenge as we consider where pandemics have historically emerged. Therefore, there is a need to identify, adapt, and develop workflows to meet the needs …


Stable Oxygen And Hydrogen Isotopic Ratios Of Precipitation And Modelling Of Precipitation Sources In Central Kentucky, Usa, 2017-2022, Ariel Gold-Mccoy Jan 2025

Stable Oxygen And Hydrogen Isotopic Ratios Of Precipitation And Modelling Of Precipitation Sources In Central Kentucky, Usa, 2017-2022, Ariel Gold-Mccoy

Theses and Dissertations--Civil Engineering

Our goals were to carry out analyses of a multi-year δ¹⁸O and δ²H dataset of precipitation from central Kentucky and to analyze the source of precipitation for storm events from 2017 to 2022. δ¹⁸O and δ²H were measured for 244 weekly precipitation samples collected by the National Atmospheric Deposition Program at Mackville, Kentucky, USA. Modelling precipitation source was carried out using HYSPLIT model for 414 events. Results of δ¹⁸O and δ²H from central Kentucky show: consistent seasonality, including summer highs and winter lows for δ¹⁸O and δ²H; correlation with air temperature; and …


Measuring Accessibility Of Electric Vehicle Charging Infrastructure: A Case Study In Kentucky, Oluwasola Elijah Fagbohun Jan 2025

Measuring Accessibility Of Electric Vehicle Charging Infrastructure: A Case Study In Kentucky, Oluwasola Elijah Fagbohun

Theses and Dissertations--Civil Engineering

This thesis assesses spatial accessibility to electric vehicle charging infrastructure across Kentucky by investigating methodological approaches to measure accessibility: provider-topopulation ratios, regional accessibility metrics, and several methods in the family of gravity models. The Enhanced Two-Step Floating Catchment Area method was employed to measure electric vehicle charging station accessibility across Kentucky using a network-based approach in ArcGIS Pro. The analysis integrated 2023 American Community Survey 5-year Census block group data, Kentucky road network datasets, charging station locations from the Alternative Fuels Data Center, and Alternative Fuel Corridor designations. We examined existing infrastructure and proposed stations outlined in the Kentucky electric …


A Scoring Approach For Evaluating And Ranking Complete Streets Projects, Eirini Stavropoulou Jan 2025

A Scoring Approach For Evaluating And Ranking Complete Streets Projects, Eirini Stavropoulou

Theses and Dissertations--Civil Engineering

Complete Streets is a vital strategy for developing an equitable transportation network that provides access to all users and transportation options to communities. A growing interest in this concept has been noted in the United States, with over 1,700 Complete Streets-related policies implemented nationwide. The Kentucky Transportation Cabinet (KYTC) has developed the “Complete Streets, Roads, and Highways Manual” and the “Complete Streets Policy” aiming to promote a safer and more inclusive transportation system statewide through Complete Streets implementation. A recent KYTC initiative was the development of a scorecard to systematically evaluate Complete Streets projects competing for funding. The scorecard is …


Adjusting Benefit Estimation For Pedestrian And Bicycle Facilities For Kentucky, Dionysios Tzamakos Jan 2025

Adjusting Benefit Estimation For Pedestrian And Bicycle Facilities For Kentucky, Dionysios Tzamakos

Theses and Dissertations--Civil Engineering

The growing shift of commuters towards active transportation (AT) in the U.S. has led transportation agencies to place greater emphasis on improving bicycle and pedestrian facilities. Such improvement efforts can be integrated into multi-modal highway planning and development or be implemented through stand-alone pedestrian and bicycle projects both resulting in additional AT demand. Measuring the benefits of infrastructure improvement is central to prioritizing projects, as active transportation contributes to health, congestion reduction, safety, and recreational benefits. This study aims to calibrate the demand estimates for walking and cycling and estimate the associated benefits for the state of Kentucky. Population density …


Advancing Vapor Intrusion Science Using Systematic Frameworks To Foster Informed Decision Making, Hong Cheng Tay Jan 2025

Advancing Vapor Intrusion Science Using Systematic Frameworks To Foster Informed Decision Making, Hong Cheng Tay

Theses and Dissertations--Civil Engineering

Vapor intrusion, the migration of subsurface vapors into indoor air spaces, is an important source of indoor air contamination to consider at hazardous waste sites contaminated by volatile organic compounds (VOCs). There is considerable uncertainty and variability in the factors that influence vapor intrusion processes, which poses a significant challenge for decision making, despite advancements in vapor intrusion science. This dissertation consolidates knowledge from existing scientific advances and investigates scientific gaps associated with the vapor intrusion preferential pathway conceptual model (i.e. conduit vapor intrusion), associated with the vapor entry pathway into buildings via sewer systems. The overall goal of this …


An Investigation Of The Legitimacy Of The Underlying Assumptions Of The Scs Curve Number Method By Application To Actual Urban Watersheds, Robert K. Peterson Jan 2025

An Investigation Of The Legitimacy Of The Underlying Assumptions Of The Scs Curve Number Method By Application To Actual Urban Watersheds, Robert K. Peterson

Theses and Dissertations--Civil Engineering

The Soil Conservation Service (SCS) Curve Number (CN) method is widely used to estimate direct runoff, and its TR-55 urban-adapted Curve Numbers are commonly applied in stormwater design. However, the underlying assumptions of the method have been the subject of contemporary review, and concerns remain that these values underestimate runoff in actual urban watersheds. This study evaluates the performance of TR-55 CNs using rainfall–runoff data from twenty real-world urban watersheds in the National Stormwater Quality Database.

Empirical Curve Numbers were derived using two calibration techniques, the asymptotic CN method (CN∞) and a nonlinear least-squares optimization method (CNLS), and …


Earthquake Wrangler: Leveraging Ios Technology For Earthquake Detection And Early Warning Application To Enhance Public Safety., Luis F. Salome Jan 2025

Earthquake Wrangler: Leveraging Ios Technology For Earthquake Detection And Early Warning Application To Enhance Public Safety., Luis F. Salome

Theses and Dissertations--Civil Engineering

Earthquakes are devastating natural phenomena and generate secondary hazards such as tsunamis, landslides and fires. Their catastrophic impacts span both developed nations including the United States, Japan, Turkey, and Italy and developing countries such as El Salvador, Haiti, Nepal and the Philippines, where disparities in early warning infrastructure remain important. Seismic events start with stress waves generated by tectonic plate motion, with body waves (P- waves and S-waves) and surface Rayleigh and love waves that carry energy through the earth. While some regions have adopted advanced early warning systems based on seismic hazard models and strong ground motion analysis, others …


Atomistic Calculations Characterizing Thermodynamic And Mechanical Properties Of High Entropy Alloys, Sarah O'Brien Jan 2025

Atomistic Calculations Characterizing Thermodynamic And Mechanical Properties Of High Entropy Alloys, Sarah O'Brien

Theses and Dissertations--Chemical and Materials Engineering

High entropy alloys (HEAs) are an exciting new class of materials. HEAs combine multiple elements in concentrations ranging from 5% to 35%. The large variation in concentrations increases the alloy’s entropy, stabilizing it. The stabilization is due to both an increased configurational entropy and increases the vibrational entropy when the alloy is at higher temperatures. This was seen for both MoNbTaW and FeNiMoW by combining the atomistic techniques: density functional theory (DFT) and density functional perturbation theory (DFPT). For MoNbTaW, the composition plays a large role in stabilizing the alloy over the configuration of elements. For the three-phase alloy, FeNiMoW, …


Augmenting Machine Learning Technique Through Natural Language, Tasmia Tasrin Jan 2025

Augmenting Machine Learning Technique Through Natural Language, Tasmia Tasrin

Theses and Dissertations--Computer Science

While artificial intelligence (AI) and machine learning (ML) have proven effective at addressing many of the challenges that we face in our everyday lives, there are many situations in which these methods struggle. Examples include environments where AI or ML systems must perform complex behaviors or those where rewards are difficult to calculate. To address this limitation, interactive machine learning (IML) techniques have been introduced, which incorporate machine-understandable human feedback into traditional ML approaches. This feedback is often given as a discrete, positive or negative numeric value. This feedback is typically provided as often as possible to convey a dense …


Harmful Algal Bloom Prediction Modeling In The Face Of A Changing Climate, Jordan E. Spears Jan 2025

Harmful Algal Bloom Prediction Modeling In The Face Of A Changing Climate, Jordan E. Spears

Theses and Dissertations--Civil Engineering

Harmful algal blooms (HABs) in rivers pose significant threats to drinking water quality and public health, yet the predictive understanding of their proliferation remains limited, particularly regarding the influence of flow conditions in large rivers. This thesis addresses the critical knowledge gap of the relationship between seasonal flow variability and HAB proliferation in the Ohio River, with the Markland Pool serving as the primary study site. This study quantified the impact of early summer high flow events (>7500 m3 s-1) and late summer to early fall low flow conditions (< 1500 m3 s-1) by integrating …


Collision Avoidance Information System Utilizing Machine Learning Image Recognition, Michael W. Long Jan 2025

Collision Avoidance Information System Utilizing Machine Learning Image Recognition, Michael W. Long

Theses and Dissertations--Mining Engineering

This thesis addresses significant safety challenges presented by powered haulage fatalities in underground mining by developing and evaluating a machine learning-driven Collision Avoidance Information System (CAIS). The research utilized a ZED 2i camera to capture both RGB and depth data for enhanced spatial awareness in visually limited underground environments. A specialized dataset of underground mining equipment was captured from limestone and zinc mines, annotated, and used to train a segmentation network. The CAIS was field-tested in diverse underground settings, achieving an accuracy of 82% in a limestone mine similar to the training data, but a lower accuracy of 45% in …


The Dynamic Material Response Of Csa Cement Using A Split Hopkinson Bar, Elliott L. Morgan Jan 2025

The Dynamic Material Response Of Csa Cement Using A Split Hopkinson Bar, Elliott L. Morgan

Theses and Dissertations--Mining Engineering

The University of Kentucky Center for Applied Energy Research (CAER) Cementitious Materials Group is developing a pourable Calcium Sulphoaluminate (CSA) cement-based concrete for rapid repair applications. Due to dynamic events like vehicle strikes, ballistic events, or other dynamic loading events, the dynamic material characteristics are important for understanding how the material will respond. A large diameter Split Hopkinson Pressure Bar (SHPB) was used to test samples of the pourable CSA cement and determine its dynamic material properties in the early strength development phase. 24 samples were tested in 7 day intervals for 28 days. Samples were prepared targeting a length …


Temporal Machine Learning For Predicting Accidents And Violations In The Mining Industry, Nathan T. Kelley Jan 2025

Temporal Machine Learning For Predicting Accidents And Violations In The Mining Industry, Nathan T. Kelley

Theses and Dissertations--Mining Engineering

This thesis examines the predictive capability of a temporal machine learning model for forecasting future accidents and violations at individual mines, based on historical data. Mine accidents were categorized by accident classification and violations were categorized by the Part Section. The primary datasets utilized were the mine safety and health administration’s (MSHA’s) Accident Injuries and Violations datasets. The available datasets were cleaned and organized by mine type and commodity, then divided into separate subsets for training, validating, and testing. Different models, cutoff metrics, learning rates, number of hidden layers, data processing methods, data processing divisions, number of points observed …


An Autonomous Robotic Inspection System For Underground Mines Using Unmanned Aerial Vehicles (Uavs), Kiazoa M. Joao Jan 2025

An Autonomous Robotic Inspection System For Underground Mines Using Unmanned Aerial Vehicles (Uavs), Kiazoa M. Joao

Theses and Dissertations--Mining Engineering

Underground mining environments pose unique safety challenges for workers due to poor visibility, unstable ground conditions, and the absence of GPS signals. To adhere to safety and health standards, underground mines are required to perform safety inspections regularly. Conventional safety inspections require personnel to enter the hazardous environment, highlighting the need for a safer, remote alternative. The use of UAVs for safety inspection in underground mines is a somewhat novel idea but has shown great promise. While Unmanned Aerial Vehicles (UAVs) cannot eliminate all hazards associated with mining, they provide critical support by accessing hazardous or restricted zones that are …


Analysis Of Dynamic And Final Surface Subsidence Movements Over Subcritical Panels In The Eastern Us, Mauricio Parra Valencia Sr Jan 2025

Analysis Of Dynamic And Final Surface Subsidence Movements Over Subcritical Panels In The Eastern Us, Mauricio Parra Valencia Sr

Theses and Dissertations--Mining Engineering

Subsidence prediction is a critical field in mining engineering, focusing on anticipating ground movements caused by underground coal extraction. Accurately forecasting these movements is essential for protecting surface structures and infrastructure from damage. However, despite extensive research by mining professionals worldwide, reliable prediction remains challenging, especially in complex environments like subcritical mining areas and locations characterized by highly variable topography. These conditions introduce non-linear rock mechanics that often complicate the application of traditional predictive models. This thesis utilizes measured subsidence data related to the extraction of two adjacent longwall panels in a deep coal mine in the eastern US to …


Analysis Of Ptfe Radial Lip Seals For Wheel Bearing Applications, Madison Vogt Jan 2025

Analysis Of Ptfe Radial Lip Seals For Wheel Bearing Applications, Madison Vogt

Theses and Dissertations--Mechanical and Aerospace Engineering

A numerical analysis was conducted to investigate the viscoelastic effects of nonlinear materials on the sealing zone and contact pressure distribution of radial lip seals in a conventional geometric topology. The use of nonlinear materials in radial lip seal applications is desirable to improve operation and reliability of rotating machinery due to their high operating temperatures, chemical compatibility, and low friction coefficients. Examples include, but are not limited to, seals within industrial air compressors, turbine engines, aircraft landing systems, chemical processing equipment, and Freon pumps. This work focuses on analyzing the nonlinear viscoelastic response of pure Polytetrafluoroethylene (PTFE) and PTFE …


Simplified Molecular Diagnostics Methods For Environmental Testing Of Pathogens And Other Applications, Mohammad Dehghan Banadaki Jan 2025

Simplified Molecular Diagnostics Methods For Environmental Testing Of Pathogens And Other Applications, Mohammad Dehghan Banadaki

Theses and Dissertations--Mechanical and Aerospace Engineering

Environmental Surveillance (ES) has emerged as a powerful tool to monitor the emergence and persistence of a pathogen within a facility or community using wastewater/water analysis. Over the past four years, implementation of ES has experienced an explosive acceleration, driven by efforts to monitor the spread of SARS-CoV-2, which has made ES a routinely used public health tool in many locations. We can now use ES to measure the emergence/presence/abundance of different viruses (e.g., SARS-CoV-2, influenza, mpox), bacteria (e.g., E. coli, V. cholerae, antibiotic-resistant strains), fungi (e.g., C. auris), and other biological markers indicative of infectious diseases. However, its broad …


Determination And Limitations Of Blocked Forces In Industrial Settings, Matthew Smither Jan 2025

Determination And Limitations Of Blocked Forces In Industrial Settings, Matthew Smither

Theses and Dissertations--Mechanical and Aerospace Engineering

Transfer path analysis methods have been used for decades to determine noise and vibration paths emanating from machinery. In its advent, the machinery source had to be disconnected from the receiver it was attached to in order to gain useful information about each. Further advances in methodology allowed for determining machinery input forces without decoupling them from the structures they were attached to. However, these methods were limited in that the machinery and structures were required to be treated as a system. Thus, any force data obtain was only useful in the configuration it was measured in. Finally, a method …


In-Situ Characterization Of Damage Mechanisms In Ceramic Matrix Composites, Cle' E. Sanchez Jan 2025

In-Situ Characterization Of Damage Mechanisms In Ceramic Matrix Composites, Cle' E. Sanchez

Theses and Dissertations--Mechanical and Aerospace Engineering

Ceramic Matrix Composites have many advantages, attracting the nuclear, aerospace, and automotive industries with their high heat stability, strength, and oxidation resistance. However, challenges are presented when machining these materials due to the brittle properties and complicated microstructure. The objective of this project was to identify damage mechanisms that occur when a CMC is orthogonally machined and the cutting mechanics are observed in-situ, followed by post-cut characterization of the as-machined surface morphology. In this analysis, the main variable is the feed rate, which can influence the damage mechanisms, such as matrix failure (matrix cracking) or fiber failure (pullout). Through this …