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

Engineering Commons™

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

Theses and Dissertations

Discipline
Institution
Keyword
Publication Year

Articles 1651 - 1680 of 11503

Full-Text Articles in Engineering

Effects Of Process Parameters On The Dimensional Accuracy Of Fused Deposition Modeled Parts, Ethan Eugene Bair May 2023

Effects Of Process Parameters On The Dimensional Accuracy Of Fused Deposition Modeled Parts, Ethan Eugene Bair

Theses and Dissertations

Fused deposition modelling (FDM) is one of the most common additive manufacturing techniques used with applications ranging from rapid prototyping at a professional scale to simple part creation at a hobbyist scale. FDM printing has very little in terms of information based on how accurate printed parts can be. This issue, which is common amongst many different types of additive manufacturing techniques, is something that has not been studied in FDM printed parts in high volumes. Research based on the effects of process parameters on mechanical properties has been conducted in high proportions. This study focused on FDM machines using …

Go to article

A Reduced Order Model For Estimation Of Fractional Flow Reserve (Ffr) In Coronary Artery Disease: Assessing The Impact Of Side Branches, Arber Vila May 2023

A Reduced Order Model For Estimation Of Fractional Flow Reserve (Ffr) In Coronary Artery Disease: Assessing The Impact Of Side Branches, Arber Vila

Theses and Dissertations

Coronary Artery Disease (CAD) affects millions of people worldwide and remains a leading cause of morbidity and mortality. To effectively plan treatment and risk stratification, assessing CAD severity is of paramount importance. Fractional flow reserve (FFR) is a critical clinical parameter used to evaluate CAD severity, measured by the ratio of mean distal coronary pressure to mean aortic pressure during hyperemic conditions. Although non-invasive FFR estimation methods have gained popularity, computational fluid dynamics (CFD) is impractical for routine clinical use due to the time and resources required. To address this issue, a reduced order model is proposed that accurately captures …

Go to article

High-Level Requirements For Conceptual Design Of Bridge Deflection Measurement System Using Model-Based Systems Engineering, Mariana Villalabeitia Arenas May 2023

High-Level Requirements For Conceptual Design Of Bridge Deflection Measurement System Using Model-Based Systems Engineering, Mariana Villalabeitia Arenas

Theses and Dissertations

Bridges are essential in the infrastructure transportation system. Repairs and maintenance are the key activities to keep them safe for use. Over the years, the evolution of technology has been applied to improve the way bridges are designed, built, monitored, inspected, and repaired. Nevertheless, there is still a gap between the research efforts and the application of this knowledge in the practical field of bridge inspections. Model-based Systems Engineering is a formalized methodology in the system design that is centered around the model throughout all the life cycle stages of a system, supporting the requirements, design, analysis, verification, and validation …

Go to article

Determining Performance Characteristics From The Mississippi Cowling - Piper Warrior Vs. Piper Archer, Soufiane Ait Yahia May 2023

Determining Performance Characteristics From The Mississippi Cowling - Piper Warrior Vs. Piper Archer, Soufiane Ait Yahia

Theses and Dissertations

Today, Piper is one of the most used aircraft in the general aviation sector. The history of Piper Aircraft has been the subject of numerous books and research projects with over 80 years of aviation industry leadership. For aviation fanatics, the Cherokee is synonymous with Piper Aircraft Corporation. The Piper PA-28 Cherokee is a family of two-seat or four-seat light aircraft built for air taxi, flight training, and personal use. The original Piper Cherokees PA-28- 150 and PA-28-160 received their type certificate from the Federal Aviation Administration back in 1960 and the series remains in production to this day. Multiple …

Go to article

A Study To Determine Performance Characteristics Of The Mississippi Cowling - Piper Archer Vs. Piper Warrior, Zilvinas Visockas May 2023

A Study To Determine Performance Characteristics Of The Mississippi Cowling - Piper Archer Vs. Piper Warrior, Zilvinas Visockas

Theses and Dissertations

Today, aviation is one of the most technologically advanced and innovative sectors in the world. With fast-depleting natural resources, increasing environmental pollution, and continuous growth in fuel cost, efficiency has become industry’s top priority. Engineers are making gradual improvements that offer overall increase in aircraft’s performance. Drag is critical factor in aviation as it directly impacts aircraft’s fuel efficiency, range, and speed. During the design phase, engineers invest significant effort and expense in attempting to minimize the drag profile by implementing aerodynamic shapes and constantly reducing component weights. One of the real-life examples of such engineering attempts is Piper Archer, …

Go to article

Biomimicry Of Natural Reef Hydrodynamics In An Artificial Spur And Groove Reef Formation, Emilee Alaine Wissmach May 2023

Biomimicry Of Natural Reef Hydrodynamics In An Artificial Spur And Groove Reef Formation, Emilee Alaine Wissmach

Theses and Dissertations

Coral reef populations have rapidly been declining in coastal waters worldwide. Losing these ecosystems results not only in a loss of habitat and biodiversity, but also a loss of wave attenuation and subsequent coastal protection. Ongoing projects seek to rehabilitate and/or replace destroyed reefs with artificial structures like reef balls and rip-rap, but none perform as well as a healthy, natural reef. This project created scale modules mimicking the reef-crest and spur-and-groove (SAG) zones commonly found in natural reefs and used these models to support new efforts in artificial reef design. The modular structure consists of three different components including: …

Go to article

Predicting Near-Bed Sediment Transport Through Particle Image Velocimetry, Caroline Hoch May 2023

Predicting Near-Bed Sediment Transport Through Particle Image Velocimetry, Caroline Hoch

Theses and Dissertations

Erosion and accretion are coastal processes that directly affect the safety of coastal communities. Dimensionless parameters, such as the Shields and Ursell number, have historically been used to predict sediment motion in the nearshore region based on shear stress and wave linearity. This study uses particle image velocimetry to measure the velocity field of sediment within a wave flume and calculate these parameters for various wave profiles. Five regular wave trials and five irregular wave trials were run within the wave flume at varying depths to model how net transport changes as waves approach the shoreline. An instantaneous Shields number …

Go to article

A Step-By-Step Guide To Identify The Most Reliable Inventory Management System For Small Businesses Using Discrete Event Simulation And Pros And Cons Analysis: A Case Study At Camid-Florida Tech, Djalma Batista Oliveira Filho May 2023

A Step-By-Step Guide To Identify The Most Reliable Inventory Management System For Small Businesses Using Discrete Event Simulation And Pros And Cons Analysis: A Case Study At Camid-Florida Tech, Djalma Batista Oliveira Filho

Theses and Dissertations

According to the Department of Labor Statistics (2022), 20.6% of small businesses fail in their first year of operation, 42.6% fail after five years, and over 62.6% fail by their tenth year. One factor that can affect continued viability is the lack of knowledge and experience among small and medium-sized firms in inventory management. Despite the fact that inventory control is one of these businesses' most ignored management responsibilities, the expense of procuring inventory often accounts for a considerable portion of their budget. Due to poor inventory management or an inability to appropriately supervise their inventory, small firms may have …

Go to article

Soft Robot Configuration Estimation: Towards Load-Agnostic Soft-Bodied Proprioception, Christian Peter Sorensen Apr 2023

Soft Robot Configuration Estimation: Towards Load-Agnostic Soft-Bodied Proprioception, Christian Peter Sorensen

Theses and Dissertations

The objective of the work described in this thesis is the development of a configuration estimation scheme for quasi soft-bodied robots, with the end goal being accurate soft-robot proprioception to enable robotic manipulation of unknown external loads. The first chapter introduces the problem and state-of-the-art modeling methods. The second chapter presents work we did building on previous research on a novel sensing scheme for soft-bodied robotic configuration estimation. The third chapter discusses the development of a geometric shape-sensing model based on overlapping tendon-length measurements. This model is geometrically exact for a body composed of two constant curvature segments in bending. …

Go to article

A Statistical Approach For Analyzing Expectations Alignment Between Design Teams And Their Project Stakeholders, Matthew Christian Goodson Apr 2023

A Statistical Approach For Analyzing Expectations Alignment Between Design Teams And Their Project Stakeholders, Matthew Christian Goodson

Theses and Dissertations

Successful project management requires continuous communication aligning the expectations between project stakeholders and the project team. Expectations include both product expectations (how the product will look, feel, and perform) and programmatic expectations (timelines, deliverables, expenditure of project resources). In order to make the most effective use of project resources throughout the life of the project, a process or tool for quickly aligning expectations as closely as possible should be employed early on in the project. Project management literature is lacking in tools for aligning expectations, and solutions and best practices need to be determined since the current best option is …

Go to article

Gradient-Based Optimization Of Highly Flexible Aeroelastic Structures, Taylor G. Mcdonnell Apr 2023

Gradient-Based Optimization Of Highly Flexible Aeroelastic Structures, Taylor G. Mcdonnell

Theses and Dissertations

Design optimization is a method that can be used to automate the design process to obtain better results. When applied to aeroelastic structures, design optimization often leads to the creation of highly flexible aeroelastic structures. There are, however, a number of conventional design procedures that must be modified when dealing with highly flexible aeroelastic structures. First, the deformed geometry must be the baseline for weight, structural, and stability analyses. Second, potential couplings between aeroelasticity and rigid-body dynamics must be considered. Third, dynamic analyses must be modified to handle large nonlinear displacements. These modifications to the conventional design process significantly increase …

Go to article

Perfusion Pressure-Flow Relationships In Synthetic Poroelastic Vocal Fold Models, Cooper B. Thacker Apr 2023

Perfusion Pressure-Flow Relationships In Synthetic Poroelastic Vocal Fold Models, Cooper B. Thacker

Theses and Dissertations

The purpose of this research was to study perfusion pressure-flow relationships in self-oscillating synthetic poroelastic vocal fold (VF) models before, during, and after vibration. This was accomplished by developing a custom ultra-soft poroelastic material, incorporating the poroelastic material as the cover layer in a synthetic VF model, and studying the model vibratory response and the flow rate of fluid perfused through the cover layer while undergoing flow-induced vibration. The custom ultra-soft poroelastic material was developed using the method of direct templating with sucrose spheres as the sacrificial template and silicone as the infiltration medium. The average modulus of elasticity of …

Go to article

Experimental Validation Of A Vibration-Based Sound Power Method, Trent P. Bates Apr 2023

Experimental Validation Of A Vibration-Based Sound Power Method, Trent P. Bates

Theses and Dissertations

A vibration-based sound power (VBSP) measurement method is appealing because of its potential versatility in application compared to pressure- and intensity-based methods. The VBSP method is based on the well-known elementary radiators approach and is reliant on the acoustic radiation resistance matrix. Previous research has developed and validated the VBSP method for flat plates and cylinders. This thesis details work on extending the VBSP method to arbitrarily-curved structures. The approach of computing surface normal velocities from 3D velocity data measured by a scanning laser Doppler vibrometer (SLDV) is presented. This approach is validated with experimental sound power results of a …

Go to article

Factors That Influence The Recruitment And Retention Of Civil Engineers, Gina Young Souriac Apr 2023

Factors That Influence The Recruitment And Retention Of Civil Engineers, Gina Young Souriac

Theses and Dissertations

With a growing demand for civil engineers in the United States, understanding factors that influence students to choose civil engineering (CE) as a major in college, pursue an M.S. degree in CE, and persist in the CE industry can lead to valuable insights for recruitment and retention of future and current civil engineers. Additionally, understanding factors that prominently influence male and female civil engineers to persist in and depart from CE, separately, can lead to valuable insight towards improving focused recruitment and retention of both genders. This thesis includes three research studies that identify, analyze, and discuss these important factors. …

Go to article

Exploring The Impact Of Hour Of Code On Students' Cs Interest And Perceptions, Jessica Marie Yauney Apr 2023

Exploring The Impact Of Hour Of Code On Students' Cs Interest And Perceptions, Jessica Marie Yauney

Theses and Dissertations

As the focus on computer science in K-12 classrooms grows, the 'Hour of Code' program has also grown. As Hour of Code is one of the largest educational campaigns, it is worth evaluation to ensure effects are well understood so that implementation can be made most effective. This research sought to better understand the impact of Hour of Code. This thesis presents findings from a systematic review and from a quasi-experimental study. A large number of research articles have been published on Hour of Code. Systematic review identified 64 papers including reports from experiments testing the efficacy of Hour of …

Go to article

Testing Methodologies And Results Of Radiation Induced Soft Errors For A Cots Sram, Fram, And Soc, Wesley Raymond Stirk Apr 2023

Testing Methodologies And Results Of Radiation Induced Soft Errors For A Cots Sram, Fram, And Soc, Wesley Raymond Stirk

Theses and Dissertations

Methods for testing commercial off-the-shelf (COTS) digital devices at varying levels of complexity is presented and discussed as well as the results for testing a COTS SRAM, FRAM, and SoC using these methodologies in a pulsed dose rate environment at Little Mountain Test Facility (LMTF) and neutron testing at Los Alamos Neutron Science Center (LANSCE). Investigations at LMTF revealed a dependence in all three devices on the integrated dose of a single pulse of radiation, implying that the duration of radiation plays a significant role in the response. The test infrastructure necessary to dynamically access an FRAM at LMTF and …

Go to article

Rfssw Behavior Prediction Using A Numerical Model, Evan Robert Berger Apr 2023

Rfssw Behavior Prediction Using A Numerical Model, Evan Robert Berger

Theses and Dissertations

A two-dimensional axisymmetric thermo-mechanical model of the Refill Friction Stir Spot Welding (RFSSW) process was developed and validated with experimental data. Welding temperatures, tool forces, and material flow including defect formation, were accurately predicted by the model. Qualified repair techniques are critical for successful implementation of a welding process for use on large weldments with a significant number of spot joints, and this work demonstrates a repair technique for RFSSW that is validated both experimentally and numerically. Repaired properties are shown to exceed 90% of the original mechanical properties of the RFSSW process. RFSSW has different process parameters for every …

Go to article

Strength And Durability Of Plastic Clays Treated With Cement Or Lime, Tyler D. Mickelson Apr 2023

Strength And Durability Of Plastic Clays Treated With Cement Or Lime, Tyler D. Mickelson

Theses and Dissertations

The objective of this research was to compare the efficacy of portland cement to that of lime for improving the strength and durability of plastic clays. The scope of work associated with this research involved laboratory strength and durability testing of three plastic clays treated with portland cement or lime. To ensure a broad application of the work, the clays were obtained from three different regions of the United States, specifically from project sites near Bloomington, Indiana; San Antonio, Texas; and Monticello, Utah. Laboratory testing included evaluation of selected properties of the three clays in the untreated condition and in …

Go to article

Load-Deformation Behavior Of Tension-Only X-Brace Roof Truss Diaphragms, Benjamin Johnson Meek Apr 2023

Load-Deformation Behavior Of Tension-Only X-Brace Roof Truss Diaphragms, Benjamin Johnson Meek

Theses and Dissertations

The alternative seismic design provisions for diaphragms provided in ASCE 7-22 Minimum design loads and associated criteria for buildings and other structures Section 12.10.3 account for both diaphragm ductility and displacement capacity, producing more accurate design forces and decreased detailing when compared to conventional seismic design methods. However, the diaphragm design force reduction factor has not yet been determined for tension-only roof truss diaphragms, a common system used in metal buildings. In this study, experimental tests of two cantilevered diaphragm subassembly specimens with tension-only rod bracing were conducted to determine the load-deformation behavior of the system. The first specimen used …

Go to article

From Point Estimates To Predictive Distributions In Machine Learning Models - A Statistical Importance Sampling Framework, Giuseppina Carannante Apr 2023

From Point Estimates To Predictive Distributions In Machine Learning Models - A Statistical Importance Sampling Framework, Giuseppina Carannante

Theses and Dissertations

In this thesis, we leverage powerful statistical frameworks for optimal sequential estimation and tracking in non-linear and non-Gaussian dynamical models, which enjoy proven (asymptotic) optimality properties. Initially, we build upon our previous work, which employed first-order Taylor series approximation to propagate the first two predictive moments, to derive Bayesian encoder-decoder networks. This work introduced the notion of dense, pixel-level uncertainty map that is crucial in fields, such as autonomous vehicles and medical segmentation. We then extended the Bayesian framework to an ensembling scheme based on ensemble Kalman Filtering (EnKF). While EnKF represents the predictive distribution with an ensemble of draws, …

Go to article

First Episodic Atmospheric Deposition Of Nutrients To Utah Lake: Statistical Analysis And Characterization, Cristian Alun Dorrett Apr 2023

First Episodic Atmospheric Deposition Of Nutrients To Utah Lake: Statistical Analysis And Characterization, Cristian Alun Dorrett

Theses and Dissertations

Atmospheric deposition (AD) is a significant but poorly understood source of nutrients to many aquatic systems around the world. Accurate characterization of the nutrient budgets of aquatic systems is critical to good management decisions, so a better understanding of AD-related nutrient loads is essential, especially for water bodies where nutrient loads from atmospheric deposition are significant. Due to its large surface area, proximity to Great Basin dust sources, high values of atmospheric particulates due to inversions, and the high phosphorus content of local soils, Utah Lake, in the semi-arid Utah Valley, USA, experiences significant phosphorus loading from AD. The lake …

Go to article

Simulations Of Electrode Heterogeneity And Design For Lithium-Ion Batteries, Amir Sina Hamedi Apr 2023

Simulations Of Electrode Heterogeneity And Design For Lithium-Ion Batteries, Amir Sina Hamedi

Theses and Dissertations

This work develops three models for simulation of the high-current operation of Li-ion batteries. Simulation as a tool can provide understanding beyond what experiments can offer. Different types of electrodes such as graphite, silicon, and NMC are modeled to study cell performance and aging under aggressive operating conditions. The first part of this work focuses on the effect of electrode microscale lateral heterogeneity on the degradation of conventional Li-ion batteries, especially for fast-charge applications. The non-uniform pore distribution leads to the nonuniform current density and state of charge (SoC), which can finally result in non-uniform Li plating and aging. The …

Go to article

Toward Automatically Composed Fpga-Optimized Robotic Systems Using High-Level Synthesis, Szu-Wei Lin Apr 2023

Toward Automatically Composed Fpga-Optimized Robotic Systems Using High-Level Synthesis, Szu-Wei Lin

Theses and Dissertations

Robotic systems are known to be computationally intensive. To improve performance, developers tend to implement custom robotic algorithms in hardware. However, a full robotic system typically consists of many interconnected algorithmic components that can easily max-out FPGA resources, thus requiring the designer to adjust each algorithm design for each new robotic systems in order to meet specific systems requirements and limited resources. Furthermore, manual development of digital circuitry using a hardware description language (HDL) such as verilog or VHDL, is error-prone, time consuming, and often takes months or years to develop and verify. Recent developments in high-level synthesis (HLS), enable …

Go to article

Permanent Passive Fire Protection Against Wildland-Urban Interface Fires, Makenzie Wilson Apr 2023

Permanent Passive Fire Protection Against Wildland-Urban Interface Fires, Makenzie Wilson

Theses and Dissertations

The average intensity and frequency of wildland fires have been on the rise over the years, leading to an increase in the risk to homes located in the Wildland-Urban Interface (WUI). Fire suppression is the most used method of wildland fire control, but this suppression can cause wildland fires to become more frequent and devastating. Increased development in the WUI also puts these homes at greater risk. Current methods of passive fire protection are effective, but these methods are expensive, time consuming to set up, and not fully effective. This research proposes a permanent passive fire protection system that is …

Go to article

Long-Term Modulus Of Microcracked Cement-Treated Base Layers, Patrick Matthew Mcdivitt Apr 2023

Long-Term Modulus Of Microcracked Cement-Treated Base Layers, Patrick Matthew Mcdivitt

Theses and Dissertations

The objective of this research was to measure and analyze the long-term modulus values of cement-treated base (CTB) layers constructed in Utah using microcracking. Because modulus values of pavement layers are among the most influential inputs affecting mechanistic-empirical pavement design, obtaining reasonable estimates of modulus values is critical. Testing was performed with a portable falling-weight deflectometer, also called a lightweight deflectometer, and modulus values were backcalculated with the computer program BAKFAA. Testing occurred at five asphalt pavement sites in northern Utah, where reconstruction with full-depth reclamation and cement stabilization, in the form of cement slurry, was performed approximately 2 to …

Go to article

Validation And Development Of Top-Down Illumination For Optofluidic Biosensors, Matthew Marley Hamblin Apr 2023

Validation And Development Of Top-Down Illumination For Optofluidic Biosensors, Matthew Marley Hamblin

Theses and Dissertations

Lab-on-a-chip devices are changing the way that medical testing is performed by allowing rapid testing with small samples. Optofluidic biosensors are a type of lab-on-a-chip device that use light excitation on a fluid sample. One such application of an optofluidic biosensor is a device that can detect antibiotic resistant bacteria by combining DNA from a sample with fluorescent beads, flowing that sample through a hollow channel, and shining laser light on the channel. If the bacteria tested for is present, the fluorescent beads will give off photons that can be detected as a positive signal. The main method for illumination …

Go to article

Large-Scale Testing Of Lightweight Cellular Concrete Backfill For Sliver-Fill Mse Wall Configurations, Meghann Dee Morgan Apr 2023

Large-Scale Testing Of Lightweight Cellular Concrete Backfill For Sliver-Fill Mse Wall Configurations, Meghann Dee Morgan

Theses and Dissertations

Lightweight cellular concrete (LCC) is an aerated or foamed concrete where 25-80% of the concrete matrix consists of air voids. The high volume of air voids reduces the strength but significantly decreases the weight of the material, which has made it an attractive alternative to soil for retaining structure backfills. Though the use of LCC has increased, little research has been performed on the large-scale behavior of retaining structures containing LCC as backfill. This research test attempts to fill knowledge gaps found with regard to the use of LCC in a mechanically stabilized earth (MSE) wall with a trapezoidal or …

Go to article

Real-Time Facial Expression Recognition Using Edge Ai Accelerators, Mark Heath Smith Apr 2023

Real-Time Facial Expression Recognition Using Edge Ai Accelerators, Mark Heath Smith

Theses and Dissertations

Facial expression recognition is a popular and challenging area of research in machine learning applications. Facial expressions are critical to human communication and allow us to convey complex thoughts and emotions beyond spoken language. The complexity of facial expressions creates a difficult problem for computer vision systems, especially edge computing systems. Current Deep Learning (DL) methods rely on large-scale Convolutional Neural Networks (CNN) which require millions of floating point operations (FLOPS) to accomplish similar image classification tasks. However, on edge and IoT devices, large-scale convolutional models can cause problems due to memory and power limitations. The intent of this work …

Go to article

A Semantic Web Approach To Fault Tolerant Autonomous Manufacturing, Fadi El Kalach Apr 2023

A Semantic Web Approach To Fault Tolerant Autonomous Manufacturing, Fadi El Kalach

Theses and Dissertations

The next phase of manufacturing is centered on making the switch from traditional automated to autonomous systems. Future Factories are required to be agile, allowing for more customized production, and resistant to disturbances. Such production lines would have the capability to reallocate resources as needed and eliminate downtime while keeping up with market demands. These systems must be capable of complex decision making based on different parameters such as machine status, sensory data, and inspection results. Current manufacturing lines lack this complex capability and instead focus on low level decision making on the machine level without utilizing the generated data …

Go to article

Detecting Physiological Concentrations Of Alzheimer’S Associated Amyloid-Β Protein Utilizing A Cell-Based Response, Brittany Elizabeth Watson Apr 2023

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 …

Go to article

First Prev Next Last