Engineering Commons^™

Advanced Manufacturing Of Multifunctional Shape Memory Polymer Composites And Self-Healing Systems, John B. Konlan

LSU Doctoral Dissertations

The need for multifunctional light weight structures for engineering applications is on the rise. Multifunctional composites are desired because of their ability to combine multiple functionalities into one structure. The advantages of a high strength-to-weight ratio of multifunctional composites make them desirable and suitable for use in energy-efficient applications. Shape-memory polymers (SMPs) have attracted interest over the past several decades because of their multifunctional nature. They have found use in many applications such as aerospace, satellites, automobiles, textiles, and biomedical devices, where lightweight and multifunctionality are key. The self-healing nature of most SMPs makes them suitable for use in lightweight …

Examination Of A Bench-Scale Model For Post-Wildfire Flood And Water Quality Mitigation Solutions, Cheyenne Ethridge

Honors Theses

The objective of this study is to determine a potential low-cost, sustainable, and rapidly deployable solution for post-wildfire flood and water quality mitigation in communities reliant on surface water for drinking water. Coalinga, Fresno County, California was selected as a study area for a full-scale solution due to its high risk of wildfires, high social vulnerability, and relatively low community resilience. A bench-scale demonstration of the system directs water into a gravel infiltration zone surrounded by a weir perimeter and followed by a clarifier. Because of their abundance in the area, almond shells were explored as a coagulant additive to …

In-Situ Void Formation During Liquid Composite Molding For Preformed Warp, Weft, And Alternating Orientation Rtm Samples, Tanner Cal Garrett

Theses and Dissertations

Carbon fiber reinforced parts are utilized by the transportation industry due to being strong yet lightweight. The highest quality parts are made using carbon fiber (CF) pre-impregnated with resin processed in an autoclave to reduce void content. The autoclave process is expensive and takes up a large amount of space, so liquid composite molding (LCM) is a less expensive alternative. The parts produced using LCM can be manufactured to rival the mechanical performance of parts made with pre-preg in an autoclave, but concerns remain over voids. Most research pertaining to void formation has been done ex-situ by either micro-CT or …

Surface-Texture Fabrication Of Zirconia-Toughened Alumina Using Focused Ion-Beam Machining, Kameron M. Woodruff

Theses and Dissertations

Focused ion-beam machining (FIBM), a precise form of micro-machining, was tested for feasibility in the manufacturing of microscopic dimples in zirconia-toughened alumina (ZTA), a wear resistant ceramic used in artificial joint replacements. The interaction between the ion-beam and the ceramic was characterized in terms of material removal rate (MRR), surface roughness, and notable irregularities (e.g. pitting, steps at vertical faces). These characteristics were used to design and machine patterns of microscopic dimples for tribological testing. The dimple size and pattern area were limited due to a slow MRR and high cost of milling. No significant difference in the coefficient of …

Investigation Of Temperature Control's Effects In Additive Friction Stir Deposition Of Al 7050-T7451, Jason Noah Glenn

Theses and Dissertations

Additive Friction Stir Deposition (AFSD) is a friction stir based process that includes the addition of material extruding through a bore in the center of the rotating tool. The deformation of the material from the tool rotation and high pressures result in fully dense depositions printed at very high rates with forged like mechanical properties. While deposition properties of varying alloys have been increasingly published, little work has been done investigating control of the process and as with all additive processes, consistency and predictability are of significant concern before implementation can occur. One common control method implemented in Friction Stir …

Detection Of Error-Related Potentials Evoked By Haptic Feedback Of Eblow Flexion And Extension, Dylan Michael Page

Graduate Theses - Mechanical Engineering

Robotic rehabilitation systems are increasingly used to restore sensorimotor functions for individuals with disabilities. However, many assistive devices lack sensory feedback, which is essential information for user control and embodiment. Haptic feedback is a simple and non-invasive solution to provide sensory feedback through tactile stimulation. Errors in haptic feedback can reduce the device’s effectiveness. This study aims to investigate whether error-related potentials can be detected when evoked through errors in haptic feedback during elbow flexion and extension. Electroencephalography recordings showed statistically significant decreases in power spectral density under the conditions of 12.5 Hz, 2.8 and 4.0 seconds after the onset …

Isolation Structure Simulation And Measurement To Reduce Transmit-Receive Coupling In Compact X-Band Fmcw Radar, Bruce E. Averill

Theses and Dissertations

Transmit-receive isolation in a compact X-band FMCW radar antenna system is critical for system performance. A set of candidate isolation structures are explored. In the process, performance of a commercial FDTD EM simulation software package is evaluated for antenna array modelling. Noise parameters of receiver electronics on a prototype radar processing front-end are tested. Improvements to the BYU Microwave Lab RF anechoic chamber are also reported, with a focus on measurement repeatability and antenna pattern angular resolution.

Improved Soil Parameters For Lateral Pile Analysis From Full-Scale Load Tests In Cohesionless Soil, Dallin Bruce Widmer

Theses and Dissertations

One common software program developed for analyzing single laterally loaded piles is called LPILE. Soil properties are required as input into LPILE. For sands, the soil properties required are effective soil unit weight, γ’; modulus of subgrade reaction, k; and the internal friction angle,ϕ’. There are two commonly used methods to obtain ϕ’ and subsequently k: the API method and Bolton method. Using the Bolton method to determine the soil strength properties gives more accurate load deflection values with respect to measured values from field tests. The Bolton method led to a 46% reduction in the predicted deflection error compared …

Reconnaissance Investigation Of Soil-Structure Harmonics And Building Collapse Patterns In The 2024 Noto And 2016 Kumamoto Japan Earthquakes, Nathan Cole Chesnut

Theses and Dissertations

This study used ambient vibration data collected during a reconnaissance mission to assess whether harmonics between structures and the underlying soil played a significant role in the pattern of buildings that collapsed in the magnitude 7.5 Noto Japan earthquake on January 1, 2024, and the magnitude 6.2 to 7.0 Kumamoto Japan earthquake series that occurred between April 14 and 16, 2016. Portable seismometers were used to measure the natural soil and structural frequencies of vibration under ambient loading at sites in Wajima, a city located on the Noto Peninsula, and in four locations in and around Kumamoto City. Soil frequency …

Durability Of Lightweight Concrete Bridge Decks In Utah, Lorenzo Eusebi-Diehr

Theses and Dissertations

The objectives of this research were to document and compare properties of lightweight concrete and normal-weight concrete used for construction of bridge decks and approach slabs in northern Utah. The scope of work included field and laboratory testing to characterize concrete specimens obtained from three lightweight concrete bridge deck sites and the normal-weight concrete approach slabs at one of these sites, which were recommended by the Utah Department of Transportation for evaluation, as well as laboratory testing to characterize concrete specimens obtained through previous research on lightweight and normal-weight concrete bridge decks. For field testing, a distress survey was performed …

Advancing Global Flood Inundation Mapping From Srtm To Fabdem, Taylor James Miskin

Theses and Dissertations

This study evaluates how elevation and hydrography inputs influence flood extent accuracy using ARC (Automated Rating Curve), a raster-based flood inundation model. It focuses on how spatial resolution and vertical accuracy, reflecting the satellite mission from which each dataset was derived, and bare-earth processing of the DEM affect the accuracy of predicted flood extents. The assessment compares four dataset combinations--FABDEM with GEOGLOWS River Forecasting System Version 1(RFS1), FABDEM with GEOGLOWS River Forecasting System Version 2(RFS2), SRTM with RFS1, and SRTM with RFS2--across five study locations: the Suncook River in New Hampshire, North Fork Kentucky River in Kentucky, Nimishillen Creek in …

Design And Optimization Of Lattice-Integrated Plif Cages Using Additive Manufacturing And Finite Element Modeling, Olivia Draughn

Honors Theses

The customization, characterization, and development of biomedical implants through additive manufacturing (AM) and finite element methods (FEM) becomes imperative to the success of surgical operations and long-term patient satisfaction. To combat stiffness mismatches and prevent stress shielding between implant and bone tissue, lattice structures can be implemented within bone implant design to reduce the effective Young’s modulus (EYM) of the implant and to promote osteointegration within bone tissue. Lattice structures are highly customizable, three dimensionally repeated patterned unit cells that can be manipulated to mimic the porous nature of bone tissues to increase implant-bone interface longevity. The study presents the …

Optimizing A Perfusion-Compression Bioreactor Via Python Integration, Umamah Amer

Honors Theses

Bioreactors are widely used in tissue engineering to support cell and tissue growth under controlled conditions. Perfusion-compression bioreactors, like the one developed in our lab, can be used to replicate the physiological loading of bone on 3D-printed scaffolds. When seeded with osteogenic cells and subjected to mechanical loading, these scaffolds serve as a model to study osteogenesis. To simulate physiological conditions, the bioreactor must apply 1000 compression cycles at forces up to 200 N, three times daily over 14 days. Upon implementation, validation testing and experimental studies exposed several limitations in the bioreactor’s control code. The system was initially programmed …

Evervital Patch: The Design And Development Of A Continuous Cardiac Monitoring Device For Post-Operative, In-Hospital Patients, Abigail Moeller, Jonathan Seid

Honors Theses

In the United States, due to the increasing prevalence of cardiovascular disease, over 900,000 cardiac surgeries are performed annually, with projections exceeding 1.3 million by 2029. Many post-surgical patients require continuous in-hospital cardiac monitoring, which is typically conducted using electrocardiograms (EKGs). However, traditional EKG systems such as bedside cardiac monitors and cardiac telemetry monitors rely on wired leads that can easily tangle, degrade signal quality, and require frequent readjustments or replacements due to wire breakage, and for the patient, this can cause discomfort from prolonged use. To overcome these challenges, our company, CardioSync, aims to develop a wireless cardiac monitoring …

Durability Of Rapid-Setting Concrete Repairs On Pavement Panels And Bridge Decks In Utah, Steven Benjamin Burdette

Theses and Dissertations

The objective of this research was to evaluate the durability of rapid-setting concrete batched using volumetric concrete mixers and placed in a cold region. The scope of work included field and laboratory evaluations of rapid-setting concrete repairs on both pavement panels and bridge decks in Utah. Six sites in northern Utah were selected by Utah Department of Transportation (UDOT) personnel for evaluation. At the time of inspection, the repairs had been in service for 4 to 5 years. Field research included visual inspection, Schmidt rebound hammer testing, resistivity testing, and concrete sampling. Laboratory research included stiffness testing, compressive strength testing, …

Reconstruction Of Cad Models Into Single Trimmed Surfaces, Rebecca Rasmussen

Theses and Dissertations

Classical methods by which computer-aided design (CAD) geometries are represented for both design and analysis involve meshing. However, the current process of converting a CAD model into an analysis-suitable surface mesh for the automotive industry takes a significant amount of time and labor, results in a faceted representation of the original smooth geometry, and generates representations that are prohibitively expensive for use in high-order explicit dynamics computations. This research focuses on accurately and efficiently rebuilding given CAD surfaces or meshes, such as shell-like components of automotive vehicles, into smooth, single trimmed spline surface approximations (rather than typical piecewise-linear approximations), making …

The Influence Of Leaders And Managers In Commercial Construction, Samuel F. Merrill

Theses and Dissertations

This research explores how the distinct traits of leadership and management influence supervisory effectiveness and employee experiences in Utah's commercial construction sector. While leadership and management are often conflated, this study draws on foundational literature that defines leadership as people-centered, visionary, and empowering. In contrast, management is characterized as results-driven, process-oriented, and focused on control. Using survey data from 95 individuals working in commercial construction, the study evaluates how supervisors with leadership or managerial characteristics are perceived by their teams. Supervisors were categorized based on observable behaviors selected by respondents, distinguishing leadership traits from managerial traits. Supervisors identified as leaders …

Assessing The Effectiveness Of Aging Techniques On Cloning Fpga-Based Configurable Ring Oscillator Pufs, Jonathan Thompson

Theses and Dissertations

Field Programmable Gate Arrays (FPGAs) are reconfigurable devices that are used in industries that often require increased security. Physically unclonable functions (PUFs) are a security primitive used on FPGAs for device authentication and key generation. However, the output of a PUF can be susceptible to changes in the environment, such as voltage and temperature, as well as changes in device performance that occur due to transistor aging. Previous work has shown that it is possible to induce targeted accelerated aging in order to intentionally change a PUF response, even to the point of cloning one PUF to behave like another. …

Longitudinal Analysis Of Evergreen Forest Cover Dynamics In The Great Salt Lake Basin: A Landsat-Based Stochastic Classification Approach And Comparative Assessment With The National Land Cover Dataset, Kaleb Markert

Theses and Dissertations

This dissertation presents an investigation into the changes of evergreen forest cover within the Great Salt Lake Basin and its implications for regional water resources. Utilizing a Random Forest Classifier (RFC) model trained on Landsat imagery, this research developed a methodology to map and track changes in evergreen forest coverage over the period from 1984 to 2019. The initial phase of this study focused on the development of model trained within the Bear Lake sub-basin, demonstrating the feasibility of the method for analysis of coniferous coverage. The model incorporated summer and winter Normalized Difference Vegetation Index (NDVI) to enhance the …

Frost Heave Of Clayey Soils Treated With Cement Or Lime, Ammon K. Hymas

Theses and Dissertations

The objective of this research was to measure and compare the effects of portland cement and lime at low, medium, and high concentrations on the frost-heave susceptibility of multiple clayey soils with varying plasticity indices. The scope of work included laboratory frost-heave testing of three clayey soils sampled from Monticello, Utah; Bloomington, Indiana; and San Antonio, Texas. Each soil was tested with two stabilizers, cement or lime, at three concentrations, as well as with no treatment. Two replicate samples were prepared for each combination, for a total of 42 specimens. The frost-heave testing procedures for this research involved preparing specimen …

Decadal To Millennial-Scale Morphodynamic Evolution Of Microtidal Marshes, Samuel Mason Zapp

LSU Doctoral Dissertations

Tidal marshes are susceptible to rapidly converting to open water due to their low elevations within the tidal frame. A continuous supply of externally supplied mineral sediment and in situ organic material production is necessary to offset elevation losses from relative sea level rise and erosion. Complex feedbacks between hydrodynamics, the erosion, transport, and deposition of sediment, and physical modification of the landscape by the establishment of intertidal vegetation govern the spatial and temporal patterns of elevation response. This dissertation focuses on modeling how these dynamics drive marsh landscape evolution in the past, present, and into the future under changing …

Hydrologic Decision Support In The Nile Basin: Creating Status And Outlook Products From The Geoglows Hydrologic Model, Rachel Huber

Theses and Dissertations

Decision makers and stakeholders need information about current and future streamflow to make informed decisions and we show how the GEOGLOWS Hydrologic Model, known as River Forecast System (RFS), can be used to provide hydrologic status and outlook products to inform these decisions. We examine a specific use case of RFS in the Nile River Basin and how RFS is used to provide users with hydrologic status products. We work with stakeholders at the Nile Basin Initiative to assess their needs for this information. We use basic low flow calculations to compute the Standardized Streamflow Index (SSI) and the 95th …

Systematic Analysis On The Applications Of Infrastructure Asset Management In Utah, Kelvin Kozakevitch

Theses and Dissertations

Public infrastructure is essential to a region’s economic stability and quality of life, especially its rural infrastructure where most consumable and essential goods derive from. Given the high capital investment required for infrastructure development and maintenance, asset management plans (IAM) are critical. Even though academic research exists on the problems rural infrastructure management face, little is known about the actual state, barriers and causes for the challenges IAM faces in rural Utah. This study examines the current challenges and barriers in IAM among rural communities in Utah. Employing a grounded theory approach, data was collected through a two-phase methodology: phase …

Enabling Next-Generation Microfluidics Through Advances In High-Resolution 3d Printing, Matthew S. Viglione

Theses and Dissertations

This dissertation advances the field of microfluidic device fabrication through the development and application of high-resolution 3D printing technologies. The convergence of stereolithography (SLA) with digital light processing (DLP) has created unprecedented opportunities for microfluidic device fabrication, enabling truly three-dimensional structures with feature sizes approaching the single-micron scale. Building upon foundational work in custom 3D printer development, this research addresses critical limitations in 3D printing that have historically constrained microfluidic innovation, spanning multiple generations of custom 3D printers and technical innovations that have enabled the fabrication of increasingly complex microfluidic devices while enhancing resolution, repeatability, speed, and accessibility. A comprehensive …

A Low-Cost Micro Actuator Driven By Electrowetting-On-Dielectric, Behzad Parsi

Theses and Dissertations

Microfluidic techniques have been shown to address limitations of reconfigurable radio frequency (RF) antennas and filters in efficiency, power handling capability, cost, and frequency tuning. However, the current devices suffer from significant integration challenges associated with packaging, actuation, and control. Recent advances in reconfigurable microfluidics that utilize the motion of a selectively metalized plate (SMP) for RF tuning have demonstrated promising RF capabilities but have exposed a need for an accurate fluid actuation model. This research presents models for the dynamics of plate actuation under multiple scenarios. In the first phase, the mechanical motion of a moving plate (e.g. SMP) …

Balancergnn: Balancer Graph Neural Network For Imbalanced Datasets, Mallika Boyapati

Dissertations

Addressing imbalanced datasets is challenging due to machine learning models' inclination to learn the majority class. Graph construction plays a major role in determining how Graph Neural Networks (GNNs) perform on imbalanced datasets. In this research, we introduce the BalancerGNN framework to tackle highly imbalanced datasets, demonstrating its effectiveness in fraud detection as one of the case studies. This framework is designed to work for any binary node classification dataset with significant class imbalances. This research addresses the following questions: i) How effective are feature engineering techniques in the case of imbalanced datasets? ii) How do graph representation learning and …

Heavy Ion Testing Of Versal Acap Ai Engines, Caleb S. Price

Theses and Dissertations

With recent developments in artificial intelligence (AI), there has been an ever increasing need for computation power in space. These AI models are traditionally implemented on GPUs. However, these units come at a high cost in terms of weight and power usage. Due to these limitations, many organizations are turning to the Versal ACAP device, a system on chip (SOC) with hundreds of AI engines. This option delivers more computation per watt than a traditional GPU. The desire to use Versal ACAP in space has created a need to perform radiation testing on the device. Extensive testing has been performed …

Gnss-Denied Navigation Using Lte Signals Of Opportunity On Low-Cost, Low-Swap Hardware, Tyler Sweat

Theses and Dissertations

Global navigation satellite system (GNSS) navigation is crucial in the operation of unmanned aerial vehicles (UAV). GNSS signals are susceptible to jamming, spoofing, multipath, and urban canyons and may provide incorrect position information or may not be available at all. For autonomous missions, a backup for GNSS is desirable in the event that it is unavailable. Terrestrial cellular signals are a promising option for navigation because they are continuously transmitted at higher power levels. Optimizing hardware size, weight, and power (SWaP) is critical for UAVs to maximize endurance, payload capacity, and operational efficiency. We present a system that uses long-term …

Analyzing The Drivers Of Airline Profitability, Brady Noble

Honors Theses

The commercial aviation industry, despite its transformative impact on global connection and economy, has historically struggled with consistent profitability. This thesis investigates the drivers of financial success within the airline industry, with a particular focus on the relationship between passenger load factors and profitability. Passenger load factors, defined as the percentage of available seats occupied by paying customers, have emerged as a key performance indicator, offering important insights into operational efficiency and revenue generation.

The study utilizes comprehensive data from the Bureau of Transportation Statistics, encompassing quarterly metrics on revenue, load factors, operating costs, and fuel prices from 2002 to …

Improving Erosion Resistance And Revegetation Of Wildfire-Altered Soils Using Microbial Induced Calcite Precipitation, Ahsan Ali

Doctoral Dissertations and Master's Theses

Climate change is causing wildfires to occur more frequently and with higher intensity. Leading to wide range of impacts on agriculture, infrastructure, and the environment. Wildfires affect soils by burning their organic matter, resulting in an immediate deplete of nutrients and a significant reduction in nitrogen level. Wildfires also alter soils’ physical properties and make them less resistant to erosion which results in debris flows when wildfire are followed by a rainfall event. The reduced activity of microorganisms that aid in nutrient absorption makes the soil less effective in supporting plant life. Microbial Induced Calcite Precipitation (MICP) was found to …