Digital Commons Network^™

Development Of Bio-Based Organogels For The Replacement Of Silicone Elastomers In Cosmetic & Personal Care Applications, Courtney A. Lemasney

Theses and Dissertations

Silicone elastomers (SE) are a major component in many cosmetic and personal care products, providing excellent spreading properties, leaving a dry, silky feel on the skin. Unfortunately, the manufacturing of silicone is a high energy consuming process, and these products are not biodegradable. Capryloyl/glycerin/sebacic acid (CGS) copolymers are an economical, nontoxic platform for synthesizing bio-based materials with tailored properties. These polyester networks are formed through esterification with water as its only side product. By altering feed ratios and reaction conditions, final products can vary from branched fluids to highly crosslinked elastomers. This thesis investigated controlling the crosslink density of the …

Low-Power Sensor Design And Fusion To Edge Devices For High-Speed Object Detection And Enhanced Soldier Situational Awareness, Scott Patrick Wood

Theses and Dissertations

Threat detection and physiological monitoring of soldiers from fused sensor data collected in real time is currently limited to running deep neural networks with substantial computing needs. The lack of data acquisition from sensor readings and efficient detection of novel enemy signatures motivates the need for a low-power, low-cost, wireless multisensor fusion computing system. We propose the current trends in Internet of Things to deploy a chargeable, wireless multi-channel acquisition system that can be interfaced to a high speed, Single Board Computer (SBC) such as the NVIDIA Jetson Orin capable of running object detection models, such as YOLOv7-tiny to enable …

Improved Parameters Of Anand Model And Advanced Fea Technique For Low-Cycle Fatigue Life: Finite Element Analysis Models For Pb-Free Solder And Pb Solder In Real Life Ball Gird Ally Package, Hamidreza Nahavandi

Dissertations and Theses

The present study uses the finite element method to evaluate the fatigue life of solder joints of plastic ball grid array packages (PBGA) under thermal-cycling conditions. A Series of precise 3D FE models for solder joints of plastic ball grid array packages is created to improve reliability prediction accuracy. Damage parameters are obtained from the FEA results and used to estimate solder balls’ thermal fatigue life. The Coffin-Manson equation is employed. The predicted thermal fatigue lives are discussed in detail.

Due to marketing and legislative pressures, Pb-free solder is fast becoming a reality in electronic manufacturing. The industry has concluded …

Engineering-Enhanced Theatre: How Engineering Involvement Can Aid Regional Theatres, Albert M. Le

Architectural Engineering

Engineering and theatre are disciplines not often associated with each other within regional and small theatre companies in the United States. The distinction between the two fields of study is not simply from the fundamental differences between how each field is taught and practiced, but also the difficulties encountered within a scope of theatre often constrained with limited budget and time for each production. However, when beginning to explore the intersection between engineering and theatre, it is found that the empirical nature of current theatrical practices can be countered, and scenic design and construction can be re-envisioned with engineering involvement …

Enhancing Ammonium And Bicarbonate Tolerance In Chlorella Sorokiniana Through Ems-Induced Mutagenesis, Wentao Yang

McKelvey School of Engineering Theses & Dissertations

This study explores the enhancement of ammonium and bicarbonate tolerance in Chlorella sorokiniana via EMS-induced mutagenesis, aimed at improving the microalgae's resilience and growth under high-stress conditions of elevated NH4+ and HCO3 concentrations. By mutating C. sorokiniana using EMS, we developed mutant strains capable of thriving in conditions that are inhibitory to the wild type strain. The successful adaptation of these strains demonstrates a significant increase in biomass production and tolerance to environmental stressors, highlighting the potential of EMS mutagenesis in industrial algal applications for sustainable biofuel production and environmental remediation.

Innovations To Increase Plywood Shear Wall Design Capacity And Resiliency, "Mega Walls", Through Ductile Metal Strapping, Trevor Douglas Reichenberg, Tara Suzanne Reich, Katelyn Marie Lowry

Architectural Engineering

The researchers of this project are three undergraduate Architectural Engineering students at California Polytechnic State University, San Luis Obispo. Plywood shear walls are common structural elements in timber structures that resist lateral forces. Since their introduction to the industry in the 1950s, their shear capacities have remained essentially unchanged amongst the innovations of other wooden lateral systems. Prior to this project, Cal Poly undergraduate researchers have taken on the challenge of modernizing the shear wall. The “MeGa Wall” project was born: a system that implements metal gauge strapping which enhances a conventional wall by reducing nail connection failures. Full-scale experimental …

Seal Counting On Our Plages (S.C.O.O.P.), Kaanan Kharwa

Master's Theses

The Vertebrate Integrative Physiology (VIP) lab monitors the population of northern elephant seals at the largest mainland breeding colony, located at Piedras Blancas (San Simeon, CA). As the population expands, more human-seal interactions and conflicts over land use occur. The VIP lab's work informs California State Parks and helps with the management of the rookery. Currently, members of the VIP lab fly a drone over the beaches, capture multiple images, and manually count the seals, which takes around 14 to 21 hours of analysis per survey. Machine learning methods such as Convolutional Neural Networks (CNN) and Region-based Convolutional Neural Networks …

Validation Of Mobile Devices In Arbitrary Locations Against Force Plate Standard For Balance Assessment, German J. Ellsworth

Master's Theses

With balance assessment being essential to the prediction of fall risk and detection and assessment of motor disorders, increasing clinical accessibility to objective balance metrics is essential. Work has been done validating center of mass (COM) acceleration metrics against well regarded force plate center of pressure (COP) position standards for mobile device data acquisition systems, but most research is restricted to devices being close to the COM or strapped in a harness configuration. Through the use of rigid body kinematics and the inverted pendulum model, this study develops novel methodology for calculating COM acceleration using mobile devices in arbitrary positions, …

Dynamic Maze Puzzle Navigation Using Deep Reinforcement Learning, Luisa Shu Yi Chiu

Master's Theses

The implementation of deep reinforcement learning in mobile robotics offers a great solution for the development of autonomous mobile robots to efficiently complete tasks and transport objects. Reinforcement learning continues to show impressive potential in robotics applications through self-learning and biological plausibility. Despite its advancements, challenges remain in applying these machine learning techniques in dynamic environments. This thesis explores the performance of Deep Q-Networks (DQN), using images as an input, for mobile robot navigation in dynamic maze puzzles and aims to contribute to advancements in deep reinforcement learning applications for simulated and real-life robotic systems. This project is a step …

A Data-Driven Framework For Analyzing And Predicting Social Media Engagement During Rumor Propagation, Joseph E. Faza

Master's Theses

The spread of rumors on social media has become a significant concern, as platforms like X (formerly known as Twitter) enable rapid dissemination of unverified information. These rumors can shape public perception and behavior, making it crucial to understand the dynamics of their spread. The main objective of this study is to explore how users interact with rumor-related tweets and identify key factors that predict tweet engagement. By analyzing tweets from seven different rumor events, this research aims to uncover patterns in user engagement and provide insights into the spread of misinformation. The study utilized a dataset of tweets from …

Assessment Of Dune Change Using Historical Aerial And Satellite Photos, Topographic Surveys, And Wave Data At Toro Creek Beach, Owen D. Emerson

Master's Theses

Coastal sand dunes play an important role in the littoral processes of California’s coastline. Functioning as both source and sink for sand, these dunes often protect coastal infrastructure and provide a buffer between anthropogenic development and coastal forces. At Toro Creek Beach, north of Morro Bay California, recent extreme winter storms have raised concerns about the erosion of the sand dunes that front California State Highway 1. This thesis attempts to characterize the historical growth and recession patterns of the Toro Creek dunes since 1977, the dune movement over the 2023-2024 winter seasons, the wave forcings behind recent high erosion …

Machine Learning Framework For Predicting Reliability Of Solder Joints, Robert Lee Jones

Dissertations and Theses

This paper presents the techniques and framework to produce an explainable machine learning model for predicting the reliability of solder joints exposed to thermal cycle testing. While machine learning techniques have become prevalent for many engineering and data analysis tasks, the complexity of the model occludes valuable information which can be used to refine the data, tune model parameters, and aid in scientific discovery. By exposing the relationships within the model, users can have greater confidence in the use and employment of it. The purpose of this study is to show how useful relationships can be obtained from a traditional …

A Novel Perfused Contusion Spinal Cord Injury Model To Assess Rapid Mechanical Properties Changes After Blood Spinal Cord Barrier Breakdown, Laura De Marchi

Theses and Dissertations

Blood-spinal cord barrier (BSCB) disruption exacerbates the tissue damage caused by spinal cord injury (SCI), but the mechanisms and dynamics of how the barrier breakdown affects the mechanical properties of the tissue remain unclear. The perfused bovine ex vivo indentation injury model described here represents a new platform to investigate the short-term effects of altered blood flow and vascular permeability following traumatic spinal cord injury. Our results indicate that injured cords exhibit changes to bulk perfusion, as evidenced by laser speckle contrast imaging, in addition to decreased barrier function shortly after injury. Indentation tests that simultaneously simulate a crush injury …

Prostate Tissue Motion Tracking And Ultrasound Elastography Using Tissue Mechanics Derived Constraints, Tristan S. Curry

Electronic Thesis and Dissertation Repository

Current prostate cancer detection methods can be costly to obtain, such as magnetic resonance imaging, or lack specificity, such as a digital rectal exam. Ultrasound elastography, a method that can be used to develop and test algorithms that output stiffness, strain, and displacement data captured by ultrasound radio frequency readings, offers a potential solution to these challenges. An initial algorithm utilizing dynamic programming and analytic minimization estimates the radial and angular displacements from a pre- and post-compression data set to determine the required material properties. This estimate of displacements is then refined through an algorithm where incompressibility, Laplacian smoothing, and …

Towards The Development Of Wearable Tremor Suppression Systems Combining Functional Electrical Stimulation And Mechanical Actuation, Zahra Habibollahi

Electronic Thesis and Dissertation Repository

Parkinson's disease (PD), the second most prevalent neurological disorder, is characterized by motor and non-motor symptoms including tremor. Wearable tremor suppression devices (WTSDs), have shown promising results for tremor reduction, using functional electrical stimulation (FES) or active actuators. However, results and study procedures are not consistent in the literature. Although stimulations below and above motor threshold can suppress tremor, the mechanisms of the first is still not clear, and the second might lead to muscle fatigue and discomfort over time. While active actuators have shown better results for tremor suppression, they are often heavy and bulky for daily use. Lastly, …

Contributions To The Understanding Of Turbulent Boundary Layers Over Curved Walls, Nicholas Zhu

Doctoral Dissertations and Master's Theses

A wind tunnel campaign was conducted to investigate the DARPA Suboff boundary layer. To emphasize the axisymmetric boundary layer, the generic submarine model's sail, appendages, and propeller were omitted. The study focused on the afterbody from 70–95% of the model length to examine the concurrent pressure gradient and wall curvature effects, which are commonplace in engineering. Three particle image velocimetry (PIV) configurations were employed to measure the boundary layer in detail: one spanned the entire afterbody, another had narrow strips sampled at 16 kHz, and the third used two simultaneous orthogonal measurement planes. Considerable effort was made to reduce the …

Functional Near-Infrared Spectroscopy As A Bedside Neuroimaging Tool For Neonatal Brain Monitoring And Injury Characterization, Lingkai Tang

Electronic Thesis and Dissertation Repository

Early brain injury in neonates is a common neurological complication associated with high mortality rates and long-term morbidities. Two common types of injury are intraventricular hemorrhage (IVH) and hypoxic ischemic encephalopathy (HIE). Currently used clinical neuroimaging tools for diagnosing or monitoring the injury have limitations, e.g., cranial ultrasound is not for continuous monitoring of the evolution of injury so it could miss the optimal timing for intervention, and magnetic resonance imaging (MRI) is not very accessible for infants in neonatal intensive care unit. Functional near-infrared spectroscopy (fNIRS) can be an alternative imaging technique as it can be used at the …

Creating A Wholistic Manufacturing Score To Highlight The Effects Of Hidden Inefficiencies In Automated Manufacturing Caused By Soft Dedication And Preventative Maintenance Failures, Oded Tal

LSU Doctoral Dissertations

The semiconductor industry is one of the most advanced manufacturing sectors, operating at an unparalleled scale and complexity. A new manufacturing facility costs between $500 million and $15 billion, and the industry's investment in automation is unmatched. However, the intricate and cyclical nature of semiconductor manufacturing creates very complex manufacturing facilities where the boundaries between planning and real-time operations often blur.

For the industry to keep improving, there is a need to create a new method that allows comparison among different manufacturing environments to uncover hidden losses that may be obscured by automation.

To better understand these hidden losses, the …

Modular Open-Source Photovoltaic-Powered Dc Nanogrid For Application-Specific Designs, Md Motakabbir Rahman

Electronic Thesis and Dissertation Repository

Decreasing cost of green energy producing solar panels has significantly boosted their popularity. Despite this, the power electronics associated with PV systems remain closed-source, expensive, and not easily compatible or expandable. This limits accessibility, especially for low-power applications. This research addresses these issues by adopting and analyzing DC nanogrid technology, converting it into a modular, open-source hardware system that users can easily assemble and expand. Detailed small signal analysis of the DC nanogrid was conducted, followed by the design of controllers and an effective energy management system. The system's stability was also thoroughly analyzed. Subsequently, hardware was developed and tested …

A Coarse-Grained Molecular Dynamics Study Of Gas Hydrate Formation And Dissociation, Meisam Adibifard

LSU Doctoral Dissertations

The study of gas hydrates has increased significantly over the last two decades because of their potential application in energy storage, production and transportation, water desalination, refrigeration, gas separation, etc. There is a significant interest in commercially developing natural gas hydrates because the energy content of methane hydrate reservoirs (MHRs) is at least twice that of all conventional fossil fuels combined. Additionally, due to the higher storage capacity of hydrates, it is proposed to sequester CO₂ in the form of CO₂ hydrate, thereby reducing the amount of greenhouse gases. Hence, hydrates offer a dual solution to two of …

Approximate Computing And In-Memory Computing: The Best Of The Two Worlds!, Mohammed Essa Fawzy Essa

Theses and Dissertations

Machine learning (ML) has become ubiquitous, integrating into numerous real-life applications. However, meeting the computational demands of ML systems is challenging, as existing computing platforms are constrained by memory bandwidth, and technology scaling no longer yields substantial improvements in system performance. This work introduces novel hardware architectures to accelerate ML workloads, addressing both compute and memory challenges. In the compute domain, we explore various approximate computing techniques to assess their efficacy in accelerating ML computations. Subsequently, we propose the Approximate Tensor Processing Unit (APTPU), a hardware accelerator that utilizes approximate processing elements to replace direct quantization of inputs and weights …

Enhancing Strawberry Disease And Quality Detection: Integrating Vision Transformers With Blender-Enhanced Synthetic Data And Swinunet Segmentation Techniques, Kimia Aghamohammadesmaeilketabforoosh

Electronic Thesis and Dissertation Repository

Agricultural productivity in strawberry cultivation was enhanced through the application of machine learning in this study. Traditional methods for detecting diseases and assessing ripeness in strawberries were identified as labor-intensive and error-prone, which limited farming efficiency and reduced crop yields. To address these challenges, it was hypothesized that advanced machine learning models incorporating attention mechanisms could significantly improve these tasks. The objective was to evaluate the effectiveness of various models by optimizing them for specific agricultural applications. Two datasets of strawberry images were augmented, and three pretrained models—Vision Transformer (ViT), MobileNetV2, and ResNet18—were fine-tuned. Data quality was improved through background …

Erodibility Of Sand-Silt-Xanthan Gum Mixtures, Edwin Kotey

Theses and Dissertations

The high frequency of earthen embankment failure recorded during floods has led to the general rule that embankments should not be overtopped. This notwithstanding, overtopping cannot be entirely avoided particularly during extreme events, such as winter storms and hurricanes. Reducing soil erodibility is thus fundamental to prevent and control disasters caused by embankment failure. Recent studies have explored the use of environmentally friendly additives, such as biopolymers, to improve soil properties. Geotechnical tests have shown that biopolymers can effectively increase soil strength, but little is known about biopolymer-treated soil resistance to erosion by flowing water. Results of flume experiments to …

The Effect Of Chromium Coatings On Hydrogen Uptake In Zirconium Alloy Nuclear Fuel Cladding, Jorie Lyn Walters

Theses and Dissertations

The amount of hydrogen in a nuclear reactor can have a profound impact on its performance and safety when it is absorbed into or released from fuel rods. Hydrogen pickup in modern fuel cladding materials has been minimized by alloying additions and microstructural texture engineering, but these materials are still susceptible to hydrogen release during high temperature oxidation. The nuclear accident at the Fukushima Daiichi power plant in 2011 resulted in hydrogen gas production and subsequent explosions which led the United States Department of Energy to initiate a program to develop enhanced nuclear fuel cladding materials. New cladding materials include …

B-Spline Impulse Response Functions For Transient Ssi Analysis Of Pile Foundations, Kingsley C. Ozegbe

Theses and Dissertations

The advent and consequential advancements in geotechnical earthquake engineering has made soil-structural analysis (SSI) an important component in the analysis and design of earthquake resistant structures. The filtering effects of pile foundations which reduces the seismic demand on pile-supported superstructure when they are subjected to seismic waves have been investigated and confirmed by several researchers in the last 40 years. To this end, several methods of analyzing the effects of SSI have been developed over the years. From the simplified Winkler model to the more robust finite element method (FEM) and boundary element method (BEM), researchers and structural engineers alike …

End-To-End Full-Width Induction Welding Of Unidirectional Tape-Based Thermoplastic Composites, Jaspreet Singh Pandher

Theses and Dissertations

The current large scale application of thermoset composite materials in large, twin aisle, civil transport aircraft have resulted in significant performance enhancements, such as aerodynamic efficiency, weight reduction, and durability. These large aircraft are, however, produced in relatively low numbers. For the next generation smaller single aisle aircraft, large scale applications of composites are of interest in the airframe. Application of composites in single aisle aircraft will require not only proof of similar and/or significant performance improvements, but also proof of adequate manufacturing rates. One option to achieve both is large scale application of thermoplastic instead of thermoset composites.

Thermoplastic …

Classifying Floor Accelerations For Gait Estimation And Detection, Jean Michel Franco Lozada

Theses and Dissertations

Structural vibrations are traditionally used to learn about structural systems, such as determining the dynamic characteristics of a structure and evaluating its structural performance under certain dynamic loads. Recently, researchers have proposed the use of structural vibrations to know more about the occupants of the structure in addition to the structure itself. One example of such would be to determine when a person falls, or to identify the location of a person walking in a building. Using structural vibrations to study occupants can be directly applicable to many fields, ranging from healthcare to security applications. One powerful use of structural …

Thermodynamic Modeling Of Uranium Nitride With Select Actinides And Fission Products, Eric Reece Mcmanus

Theses and Dissertations

Uranium mononitride fuel is being investigated as a potential nuclear fuel for a Westinghouse lead-cooled fast reactor due to factors such as its high uranium density, high melting point, and favorable thermal conductivity. To obtain an understanding of the thermochemical behavior of UN fission products and minor actinides, thermodynamic data was obtained from various resources to create a database to represent the behavior of the fuel. This database was used to generate an Ellingham diagram to represent the relative thermodynamic stability of the phases over the reactor temperature range. A simulation was run computing the equilibrium state of the fuel, …

Uav-Based Tracking And Following Of Railroad Lines, Keith Michael Lewandowski

Theses and Dissertations

Given the pivotal role of the railroad industry in modern transportation and the potential risks associated with track malfunctions, the inspection and maintenance of railroad tracks emerges as a critical concern. While existing solutions excel in performing accurate measurements and detection, they often rely on large, expensive, and time-consuming platforms for inspections. This project, however, seeks to solve the same problem with the use of an unmanned aerial vehicle (UAV), significantly reducing time and cost while maintaining detection capabilities. In particular, this solution is ideal for large-scale, high-level inspections following major events such as floods [6], hurricanes [7] or earthquakes …

Microchannel Slip Flow Characteristics By Time Travel After Photobleaching Velocimetry, Brandon James Sellers

Theses and Dissertations

Interfacial science follows the study of observing behavior between two or more phases of matter when in contact. For example, a liquid solution passes through a microchannel, and the walls interact with the fluid shearing along the surface. The fluid particles develop momentum changes from interfacial phenomena and slip along the wall begins to affect the fluid body. Slip flow is a name for the phenomenon, and with it, modeling velocity for the interfacial behavior demands both resolution and minimal interference. Laser-induced fluorescence photobleaching anemometry (LIFPA) works as a sound method for acquiring data on microchannel flow, but it needed …