Digital Commons Network^™

Numerical Evaluation Of Forces Affecting Particle Motion In Time-Invariant Pressurized Jet Flow, Donald E. Peterson

Theses and Dissertations

This work evaluates the relative significance of forces determining the motion of a pulverized coal particle under conditions representative of a pressurized oxy-coal combustor. The gravity force and surface forces of drag, fluid stress, added mass, and Basset history are discussed and appropriate forms of these force equations are chosen, with a consideration of spherical and non-spherical drag and the Basset history kernel. Studies from the literature that emphasize specific forces are used to validate the implementation of the force equations and correlations. Modeling is based on time-averaged, one-dimensional motion of a single non-reacting particle along the centerline of a …

Continuous-Time Trajectory Estimation And Its Application To Sensor Calibration And Differentially Flat Systems, Jacob C. Johnson

Theses and Dissertations

State estimation is an essential part of any robotic autonomy solution. Continuous-time trajectory estimation is an attractive method because continuous trajectories can be queried at any time, allowing for fusion of multiple asynchronous, high-frequency measurement sources. This dissertation investigates various continuous-time estimation algorithms and their application to a handful of mobile robot autonomy and sensor calibration problems. In particular, we begin by analyzing and comparing two prominent continuous-time trajectory representations from the literature: Gaussian processes and splines, both on vector spaces and Lie groups. Our comparisons show that the two methods give comparable results so long as the same measurements …

A Polarizable Molecular Dynamics Potential For Molten Salt Property Prediction, Jared Thurgood

Theses and Dissertations

The present study attempts to find an alternate computational tool to model the complex physical interactions within the molten salt FLiNaK in a way that is both efficient and accurate. Additionally, this study seeks to describe the effects of several different types of impurities on the FLiNaK salt system. This study selects two different polarizable force fields, the AMOEBA polarizable approach and the polarizable ion model, to determine the density and the structure of the impure FLiNaK salt mixtures at typical operating temperatures in molten salt reactors (between 500-900 °C). This study conducts ab initio molecular dynamics (AIMD) simulations and …

Experimental Characterization Of Internal Wave Generation By Multiple Ridge Topographies, Natasha J. Wilson

Theses and Dissertations

Internal waves are three dimensional waves that occur in stratified fluids, where density increases with depth, such as the ocean and atmosphere. In the oceans, internal waves are continuously generated by tidal flow over subsea topography. The size and shape of the topography, as well as the stratification relative to the oscillation frequency influence the characteristics of the generated internal wave field. To advance the current understanding of how ridges on a subcritical topography changes the internal waves generated, four symmetric topographies are used with ridge numbers ranging from three to six. An additional single ridge topography is used, as …

Deployable Mechanisms And Applications For Minimally Invasive Surgery, Jacob L. Sheffield

Theses and Dissertations

This thesis explores techniques to utilize deployable, developable, and compliant mechanism design principles while investigating applications for minimally invasive surgery. This work also examines contemporary outreach strategies to broaden awareness and expand dissemination avenues of engineering research. The outcomes of this research aim to (i) equip product designers with machine design tools, (ii) deliver background and designs to mitigate surgical frustration and procedure complications associated with obstructed laparoscope lenses during laparoscopic surgery, and (iii) provide engineering researchers with new tools to extend the impact of their research. Part one of this work (Chapter 2) introduces methods for embedding linear-motion mechanisms …

Prediction Of Transient Hydrogen Flow Of Proton Exchange Membrane Electrolyzer Using Artificial Neural Network, Mohammad Biswas, Tabbi Wilberforce, Mohammad A. Biswas

Mechanical Engineering Faculty Publications and Presentations

A proton exchange membrane (PEM) electrolyzer is fed with water and powered by electric power to electrochemically produce hydrogen at low operating temperatures and emits oxygen as a by-product. Due to the complex nature of the performance of PEM electrolyzers, the application of an artificial neural network (ANN) is capable of predicting its dynamic characteristics. A handful of studies have examined and explored ANN in the prediction of the transient characteristics of PEM electrolyzers. This research explores the estimation of the transient behavior of a PEM electrolyzer stack under various operational conditions. Input variables in this study include stack current, …

Ph-Dependent Solution Micellar Structure Of Amphoteric Polypeptoid Block Copolymers With Positionally Controlled Ionizable Sites, Meng Zhang, Yun Liu, Xiaobing Zuo, Shuo Qian, Sai Venkatesh Pingali, Richard E. Gillilan, Qingqiu Huang, Donghui Zhang

Faculty Publications

While solution micellization of ionic block copolymers (BCP) with randomly distributed ionization sites along the hydrophilic segments has been extensively studied, the roles of positionally controlled ionization sites along the BCP chains in their micellization and resulting micellar structure remain comparatively less understood. Herein, three amphoteric polypeptoid block copolymers carrying two oppositely charged ionizable sites, with one fixed at the hydrophobic terminus and the other varyingly positioned along the hydrophilic segment, have been synthesized by sequential ring-opening polymerization method. The presence of the ionizable site at the hydrophobic segment terminus is expected to promote polymer association toward equilibrium micellar structures …

Decentralized Sensor Fault-Tolerant Control Of Dc Microgrids Using The Attracting Ellipsoid Method, Ehab Bayoumi

Mechanical Engineering

System stability deterioration in microgrids commonly occurs due to unpredictable faults and equipment malfunctions. Recently, robust control techniques have been used in microgrid systems to address these difficulties. In this paper, for DC-islanded microgrids that have sensors faults, a new passive fault-tolerant control strategy is developed. The suggested approach can be used to maintain system stability in the presence of flaws, such as faulty actuators and sensors, as well as component failures. The suggested control is effective when the fault is never recognized (or when the fault is not being precisely known, and some ambiguity in the fault may be …

Autonomous Shipwreck Detection & Mapping, William Ard

LSU Master's Theses

This thesis presents the development and testing of Bruce, a low-cost hybrid Remote Operated Vehicle (ROV) / Autonomous Underwater Vehicle (AUV) system for the optical survey of marine archaeological sites, as well as a novel sonar image augmentation strategy for semantic segmentation of shipwrecks. This approach takes side-scan sonar and bathymetry data collected using an EdgeTech 2205 AUV sensor integrated with an Harris Iver3, and generates augmented image data to be used for the semantic segmentation of shipwrecks. It is shown that, due to the feature enhancement capabilities of the proposed shipwreck detection strategy, correctly identified areas have a 15% …

Black Experiences With Community Gardening In Southeast Louisiana, Kiarah Craft

LSU Master's Theses

Community gardens have been rising in popularity over the past few years (Mayers, 2023). In response to the COVID-19 pandemic, many people across the United States have decided that it is crucial to grow their own food and develop sustainability within their community. Historically, Black communities have been underserved and ignored, especially in relation to food security and community safety (White, 2019, Penniman, 2018). The purpose of this study was to collect information about the effects of community-based gardening programs on Black people in Southeast Louisiana. Additionally, the researcher would like to gain knowledge regarding the reasons that Black people …

Exploring The Role Of Salt-Tolerant Halomonas Inoculant In Altering Plant Gene Expression To Improve Salt Tolerance In Alfalfa., Ashley Kay Miller

Theses and Dissertations

Soil salinity is an increasing problem facing agriculture in many parts of the world. Climate change and irrigation practices have led to decreased yields of large areas of farmland due to increased salt levels in the soil. Irrigation introduces salts to the soil that with time accumulate and threaten crop yield. In arid climates like Utah, the practice of irrigation is especially threatening to salt-sensitive crops including alfalfa (Medicago sativa). Plants that have tolerance to salt are needed to feed livestock and the world's population. One approach to address this problem is to introduce genes encoding salt tolerance into the …

Efficient And Secure Digital Signature Algorithm (Dsa), Nissa Mehibel, M'Hamed Hamadouche

Emirates Journal for Engineering Research

The digital signature is used to ensure the integrity of messages as well as the authentication and non-repudiation of users. Today it has a very important role in information security. Digital signature is used in various fields such as e-commerce and e-voting, health, internet of things (IOT). Many digital signature schemes have been proposed, depending on the computational cost and security level. In this paper, we analyzed a recently proposed digital signature scheme based on the discrete logarithm problem (DLP). Our analysis shows that the scheme is not secure against the repeated random number attack to determine the secret keys …

Socio-Economic Determinants Of Gender-Based Violence [Gbv]: Sdg Analytics On The Global Gbv Scenario With Special Reference To Technology Facilitated Gender-Based Violence And Adolescent Birth Rates, Chandra P. Daniel

NYMC Student Theses and Dissertations

Gender-based violence (GBV) is a multifaceted problem. The most rapidly increasing modern form of violence is the intertwined epidemic of ‘Technology Facilitated GBV’ [TF GBV] and sexual violence against women and girls. It was critical to investigate the global impact of this epidemic during COVID-19 since a disproportionate impact of violence was observed among women and girls in low and middle-income countries. A retrospective cross-sectional research design was adopted using linear regression analysis (univariate and multivariate) on SDG 5.2, a set of global indicators, to elicit the socioeconomic determinants of GBV. Phase-I results exposed the top-four socio-economic determinants …

3rd Party Ip Encryption From Netlist To Bitstream For Xilinx 7-Series Fpgas, Daniel Hutchings

Theses and Dissertations

IP vendors need to keep the internal designs of their IP secret from the IP user for security or commercial reasons. The CAD tools provided by FPGA vendors have some built-in functionality to encrypt the IP. However, the IP is consequently decrypted by the CAD tools in order to run the IP through the design flow. An IP user can use APIs provided by the CAD tools to recreate the IP in an unencrypted state. An IP user could also easily learn the internals of a protected IP with the advent of new open-source bitstream to netlist tools. The user …

An Assessment Of Cattle Traffic On, And Seed Dispersion Patterns Of, Sclerocactus Wrightiae, David D. Lariviere

Theses and Dissertations

Cattle grazing has been a historic use of rangelands in Utah since Pioneer settlement in the mid 1800's. Wright fishhook cactus is a small globose cactus endemic to an area of 280,000 ha in south-central Utah and was listed as endangered in October of 1979, by the U.S. Fish and Wildlife Service (USFWS). By 2010, concerns were expressed that soil compaction in proximity to the cactus posed a threat to this species, though there was no empirical data to support such concern. In order to assess the impact of cattle traffic on Wright fishhook cactus, we used an imprint device …

Evapotranspiration In Urban And Agricultural Systems With Interacting Irrigation And Nitrogen Fertilizer Treatments, Samantha R. Shumate

Theses and Dissertations

Nitrogen (N) fertilizer and irrigation are important inputs for all managed plant species, especially in arid and semi-arid climates. The interaction between N management and irrigation can lead to more sustainable practices. This is true for both agricultural and urban environments. Precision nutrient management has been widely adopted by producers in recent decades, and water conservation has become an important goal for turfgrass managers. In urban systems, our goal was to evaluate Kentucky bluegrass (Poa pratensis L.) to determine response to three N fertilizer rates and three irrigation rates in all possible combinations. The main and interacting treatment effects were …

Electroplating And Machining Of Silicon Carbide Wafers, Madeline Beth Thompson

Theses and Dissertations

Silicon carbide has many properties that make it a promising and desirable material for diverse applications. One such application for silicon carbide wafers is as a transparent cryogenic probe card. This thesis briefly describes the design of a probe card based on a silicon carbide wafer substrate. It includes a description of electroplating fundamentals and demonstrates the feasibility of electroplating copper onto a wafer for the formation of bond pads between the substrate and external PCB ring. The process for electroplating copper with good adhesion and quality based on metal alloy formation, current control, and materials selection is outlined. Results …

Improving Xrd Analysis With Machine Learning, Rachel E. Drapeau

Theses and Dissertations

X-ray diffraction analysis (XRD) is an inexpensive method to quantify the relative proportions of mineral phases in a rock or soil sample. However, the analytical software available for XRD requires extensive user input to choose phases to include in the analysis. Consequently, analysis accuracy depends greatly on the experience of the analyst, especially as the number of phases in a sample increases (Raven & Self, 2017; Omotoso, 2006). The purpose of this project is to test whether incorporating machine learning methods into XRD software can improve the accuracy of analyses by assisting in the phase-picking process. In order to provide …

Lumbar Skin Strain Fields In The Context Of Skin Adhered Wearables, Andrew Kent Gibbons

Theses and Dissertations

A comprehensive background is herein presented for lumbar skin strain and its effect on skin adhered wearable (SAW) products. A background of the development of computational models of the interaction of skin and novel SAWs being researched is also presented. These include products involving the use of high deflection strain gauges to measure skin strain during functional movements (FMs) as a method to address the complicated phenotyping of the etiological causes of low back pain (LBP). The background concludes with the mathematical calculation of the principal skin strain magnitudes and orientations using retroreflective marker coordinate data in a motion capture …

The Inositol Trisphosphate Receptor (Ip 3 R) Is Dispensable For Rotavirus-Induced Ca 2+ Signaling And Replication But Critical For Paracrine Ca 2+ Signals That Prime Uninfected Cells For Rapid Virus Spread, Kristen A Engevik, Jenna M Ellis, Joseph M Hyser

Faculty, Staff and Students Publications

Rotavirus is a leading cause of viral gastroenteritis. A hallmark of rotavirus infection is an increase in cytosolic Ca 2+ caused by the nonstructural protein 4 (NSP4). NSP4 is a viral ion channel that releases Ca 2+ from the endoplasmic reticulum (ER) and the increase in Ca 2+ signaling is critical for rotavirus replication. In addition to NSP4 itself, host inositol 1,4,5- trisphosphate receptor (IP 3 R) ER Ca 2+ channels may contribute to rotavirus-induced Ca 2+ signaling and by extension, virus replication. Thus, we set out to determine the role of IP 3 R Ca 2+ signaling during rotavirus …

L2 English And Language Anxiety: Accuracy, Comprehensibility, And Speech Rate Across Three Communication Tasks, W. Cole Thorpe

Theses and Dissertations

This study examines how second language (L2) English learners differ in their amount of language anxiety across three communication tasks: a formal academic speaking test, an informal casual interaction with a classmate during an activity in pairs, and a formal interview with an unfamiliar native speaker. It also addressed whether and how their language anxiety across the three tasks affected their accuracy, comprehensibility, and rate of speech. Thirty-seven intermediate-high L2 English learners participated in the three communication tasks. They also completed a general language anxiety questionnaire and three anxiety inventories--one before each task. Results demonstrated that the speaking exam caused …

Indirect Tensile Strength Of Clayey Soils Treated With Cement Or Lime, Melissa Adams Cowley

Theses and Dissertations

The objectives of this research were to evaluate the sensitivity of indirect tensile strength (ITS) test results to stabilizer type, stabilizer concentration, and curing time for multiple clayey soils with varying plasticity indices (PIs), identify cases in which an ITS of 30 psi can be obtained, and create a general linear model that predicts ITS. The scope of work included laboratory testing of three clayey soils sampled from Monticello, Utah; Bloomington, Indiana; and San Antonio, Texas. Each soil was tested using two stabilizers, cement or lime, at three concentrations, and two replicate samples were prepared for each combination. ITS testing …

Enhancing The Performance Of Microbial Fuel Cells Via Metabolic Engineering Of Escherichia Coli For Phenazine Production, Olja Simoska, Dale A. Cummings, Erin M. Gaffney, Claire Langue, Tommy G. Primo, Courtney J. Weber, Corbin E. Witt, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

One of the central roles in the design, development, and application advances in mediator-Based microbial electrochemical systems, such as microbial fuel cells (MFCs), is the establishment of efficient and successful communication between conductive electrode surfaces and microorganisms via modes of extracellular electron transfer (EET). Most microbial-Based systems require the use of artificial electroactive mediators in order to facilitate and/or enhance electron transfer. Our previous work established an exogenous phenazine-Based library as a mediator system to enable EET from the model microorganism Escherichia coli as a promising biotechnological host. However, the addition of exogenous mediators to a microbial electrochemical system has …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• NSF Grant Awarded to Dr. Jinki Kim

Deep Reinforcement Learning And Hybrid Approaches To Solve Multi-Vehicle Combinatorial Optimization Problems, Prashant Sankaran

Theses

Combinatorial optimization problems are an important class of problems often encountered in the real world involving a combinatorially growing set of feasible solutions as the problem size increases. Since exact approaches can be computationally expensive, practitioners often use approximate approaches such as metaheuristics. However, sophisticated approximate methods that yield high-quality solutions require expert help to handcraft or fine-tune the solution process to suit a given problem distribution. In recent years, artificial intelligence (AI) approaches that involve learning from data without being explicitly programmed have shown tremendous success at various challenging tasks, like natural language processing and autonomous driving. Therefore, solving …

Evaluating A Novel Fly Ash Resin-Reinforced Cement’S Interactions Under Acidic, Basic, High-Salinity, And High-Temperature Conditions, Sherif Fakher, Ali El-Sayed, Layla Sameh, Bassel Abdeltawab

Faculty Journal Articles

No abstract provided.

Multi-Color Fluorescent Microscopy And Deep Learning For Studying Eukaryotic Organelles: Unveiling Cellular Growth In A System Biology Perspective, Shixing Wang

Arts & Sciences Graduate Student Theses and Dissertations

Eukaryotic cells are building blocks to complex living systems, characterized by membrane-bound organelles. Studying how eukaryotic organelles react to cellular growth and size increase is crucial, but it demands biochemical and biophysical manipulations, as well as quantitative observation tools in microscopy. We developed a multi-color yeast strain with tagged fluorescent proteins, enabling systematic measurements of 6 organelles inside each cell using spectral confocal microscopy. These measurements provided insights into how organelle biogenesis is coordinated with cellular size and growth rate regulation via different signaling pathways. To explore cellular growth under dynamic conditions, I utilized deep learning for organelle recognition using …

Applications And Perceived Impact Of Artificial Intelligence In Academic Libraries In Nigeria, Uzoamaka Ogwo Ph.D, Francis Ibegbulem, Victor N. Nwachukwu Prof.

Library Philosophy and Practice (e-journal)

This paper expounds the application and perceived impact of Artificial Intelligence (AI) in academic libraries in Nigeria. Libraries especially in developing countries may become moribund in the 21 century unless they begin to harness new, smart and intelligent technologies for improved operations and service delivery. This research adopted a literature-based approach to x-ray the applications and perceived impact of Artificial Intelligence (AI) in academic libraries in Nigeria. Through a systematic analysis and review of literature, the study brought to limelight the current state of AI integration in academic libraries in Nigeria and its possible impact on library services, collections, users, …

Makerspaces In Schools: What Knowledge, Perceptions, And Attitudes Do Teacher Librarians In Osun State Possess?, Olukunle Akinbola Osunrinade

Library Philosophy and Practice (e-journal)

Abstract

This study examined the knowledge, perception, and attitude of teacher librarians in secondary schools in Osun State towards makerspaces. A survey research design was used, and data was collected using a questionnaire. The sample for the study consisted of 110 teacher librarians from selected secondary schools in Osun State. The study found that teacher librarians in secondary schools in Osun State have sufficient knowledge about makerspaces, particularly when it comes to the ability to select technologies that improve student teaching and learning, understanding how to choose effective teaching ways to guide students' thinking and learning in makerspaces, possess experience …

Course Experiences That Promote And Inhibit Human-Centered Design, Elizabeth A. Sanders, Molly Goldstein, Justin L. Hess

School of Engineering Education Faculty Publications

Engineers contribute to large-scale socio-technical challenges, and human-centered design offers a design thinking approach that helps engineers develop a thorough understanding of the socio-technical effects of their design work. Thus, effective strategies for assessing and teaching human-centered design are needed. This study aimed to identify course characteristics that influence how students experience human-centered design in an introductory systems engineering design course. First, we categorized open-ended written reflections to understand the degree to which students experienced human-centered design. Second, we performed a thematic analysis to characterize salient course experiences for two groups of students: (1) students who experienced human-centered design in …