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Full-Text Articles in Engineering

Catalytic Upcycling Of Waste Plastics By Induction Heating, Bernard Whajah Aug 2024

Catalytic Upcycling Of Waste Plastics By Induction Heating, Bernard Whajah

LSU Doctoral Dissertations

The development of plastics over the past half century has led to rapid technological advances; however, the long-term negative environmental impacts of these materials compel new depolymerization and upcycling strategies. Plastics are indispensable due to their unique physical and chemical properties and affordability, leading to a significant increase in production rates. However, their recycling rates lag far behind their production rates. Polyolefins like LDPE and HDPE, which are common plastics, decompose very slowly in the environment. Converting these plastics into useful products often requires high-temperature pyrolysis, resulting in undesired distributions of products.

To address this challenge, this study focuses on …


Tools For Planning Multi-Axis Vibration Qualification Tests, Marcus Edward Behling Aug 2024

Tools For Planning Multi-Axis Vibration Qualification Tests, Marcus Edward Behling

Theses and Dissertations

Vibration qualification testing is necessary to ensure that components will endure vibration-induced damage in flight. Multi-axis tests have shown the potential for improvement over single-axis tests, though they require increased planning. This work focuses on planning three critical aspects of these tests: the amount of operational next assembly to include in the test, the size of shakers to use, and the number of shakers to use. Next assembly selection is studied by varying the amount of next assembly included in the lab test, performing physical tests, and comparing the accuracy of environment reconstruction in each test. In doing so, a …


Zno Based Chemiresistive Sensor For Ammonia Detection, Anna Thomas Aug 2024

Zno Based Chemiresistive Sensor For Ammonia Detection, Anna Thomas

Theses and Dissertations

This work aims on the development of nanostructured sensing elements based on ZnO for detecting ammonia, specifically designed for applications in poultry and farm fields. To achieve this objective, we prepared sensing elements, including ZnO, CuO, WO3, NiO, ZnO/CuO, ZnO/WO3, ZnO/NiO, and rGO/ZnO, using the spray pyrolysis technique. Structural, morphological, and compositional analyses were studied using X-ray Diffraction (XRD), Field Emission Microscope (FESEM), and X-ray Photoelectron Spectroscopy (XPS), respectively. The vapour/gas detection studies of fabricated sensing elements were carried out in a home built sensing chamber.

The single oxides, ZnO, CuO, WO3, demonstrated ammonia detection in the range of 5-100 …


Design For Pullout Resistance And Global Stability Of Metallic Reinforcements In Mse Walls With Lightweight Cellular Concrete Backfill, Joshua Curt Peterson Aug 2024

Design For Pullout Resistance And Global Stability Of Metallic Reinforcements In Mse Walls With Lightweight Cellular Concrete Backfill, Joshua Curt Peterson

Theses and Dissertations

Lightweight cellular concrete (LCC) is a type of concrete that has reduced density and weight compared to traditional concrete. This is achieved by incorporating a large amount of air- filled cells or voids into the mixture. The resulting material is lighter, yet still possesses considerable strength and durability, making it suitable for a range of construction applications, especially in the case of retaining walls because of its reduced weight. Unlike traditional concrete, which can be extremely heavy and place significant stress on the supporting structure, lightweight cellular concrete reduces the pressure on the retaining wall, helping to prevent deformation and …


Utilization Of Sodium Flame Synthesis For The Formation And Deposition Of Pure Metal Materials For Applications In Additive Manufacturing, Zachariah Wargel Aug 2024

Utilization Of Sodium Flame Synthesis For The Formation And Deposition Of Pure Metal Materials For Applications In Additive Manufacturing, Zachariah Wargel

McKelvey School of Engineering Graduate Student Theses & Dissertations

Advanced material classes, such as high temperature alloys, ceramics, and refractory materials have become a key area of focus for expansion in the realm of additive manufacturing. Factors such as high melting points, material homogeneity, and physical properties such as ductility limit the application of popular additive manufacturing methods to these material classes. By utilizing sodium flame synthesis and deposition (SFD) technology, nanoparticle materials can be synthesized via combustion in a laminar co-flow diffusion burner and impacted such that the deposits can be used to manufacture designed components. By using the applicable precursor materials of metal chlorides and elemental sodium …


A Methodology For Evaluating And Comparing Unmanned Inspection Platforms In Underground And Indoor Environments, Sydney Shockley Aug 2024

A Methodology For Evaluating And Comparing Unmanned Inspection Platforms In Underground And Indoor Environments, Sydney Shockley

Graduate Theses & Non-Theses

This report summarizes a research project focused on development of a methodology for evaluating the performance of various unmanned aerial vehicles (UAVs, commonly referred to as drones) and robotic platforms in GPS-denied environments, highlighting a clear stratification based on technological sophistication and design intent. A series of flight trials were designed and implemented in various environments including indoor spaces with various geometries and obstacles, and an underground mine. These trials examined signal range from the unmanned platform to the controller, the ability to navigate through confined spaces and obstacles, the overall ease-of-use and responsiveness of controls, as well as specialized …


Demand Side Management Through Integrated Water Distribution Systems And Smart Irrigation Controllers, Nathan T. Lunstad Aug 2024

Demand Side Management Through Integrated Water Distribution Systems And Smart Irrigation Controllers, Nathan T. Lunstad

Theses and Dissertations

The innovation of electrical utilities in creating smart electrical grids has superseded that of water utilities in analogous efforts. While many water utilities are now using smart water technologies, they lack the virtual command center that allows for two-way communication for more effective forecasting, load balancing, preventive methods, emergency and master planning, and level of service delivery while ensuring environmental justice and enhancing the responsible use of resources. In this dissertation, I propose the idea of the Integrated Water Distribution System (IWDS) to overcome this challenge. IWDS coordinates management of water supply and demand in a way that benefits both …


Exploring Co-Manipulation Via A New Decomposition Of Interaction Force And An Exploration Of Signal Space In Multi-Agent Motion Primitives, Kody Blaine Shaw Aug 2024

Exploring Co-Manipulation Via A New Decomposition Of Interaction Force And An Exploration Of Signal Space In Multi-Agent Motion Primitives, Kody Blaine Shaw

Theses and Dissertations

Co-manipulation is when two or more people work together to move an object. In this work, we consider the physical co-manipulation of objects that are large and heavy enough that they are more easily handled by two or more participants. We currently lack a fundamental understanding of how people perform such tasks together, both the basic signals they use to communicate and how those signals are mapped to actions and behaviors. This work builds upon the existing body of knowledge to improve our understanding of physical co-manipulation. Specifically, interaction forces are often considered a key method for information transfer in …


Mechanochemical Correlations And Spatial Distribution Of Components In Plant Cell Walls And Extracellular Matrices, Huiyong Li Aug 2024

Mechanochemical Correlations And Spatial Distribution Of Components In Plant Cell Walls And Extracellular Matrices, Huiyong Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Plant cell walls and extracellular matrices (ECMs) are important to cellular activities in plant/animal organs. The organization of plant cell wall/ECM components (e.g., local composition, arrangement, and ultrastructure of cell wall/ECM polymers) plays a role in determining their local mechanical properties. As a result, the natural processes of cell and tissue growth, development, and function rely on the control of cell wall/ECM composition, arrangement, and ultrastructure to manipulate local mechanical properties. However, directly correlating cell wall/ECM composition, organization, and mechanics has been challenging. To overcome this barrier, one goal of this thesis is to develop probing methodologies at a sub-cellular …


Designing Behavior-Aware Ai Systems To Influence Human Decision-Making, Guanghui Yu Aug 2024

Designing Behavior-Aware Ai Systems To Influence Human Decision-Making, Guanghui Yu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Artificial intelligence (AI) demonstrates superiority over humans in many applications, such as image processing, speech recognition, and decision-making. AI systems are more efficient and accurate in information processing and computation, making them invaluable in assisting human decision-making across domains like healthcare, finance, and academia. Despite these strengths, real-world applications often involve complex, context-specific judgments and a deep understanding of human values, which current AI systems might not fully grasp. In domains requiring creativity and critical thinking, AI systems heavily rely on existing human knowledge. Humans, however, possess unique strengths such as intuition, which aids decision-making in uncertain or novel situations, …


Analysis Of Water Usage And Greenhouse Gas Emissions As Transition Fuel From Coal To Natural Gas In San Juan County, New Mexico, Tahereh Kookhaei Aug 2024

Analysis Of Water Usage And Greenhouse Gas Emissions As Transition Fuel From Coal To Natural Gas In San Juan County, New Mexico, Tahereh Kookhaei

Civil Engineering ETDs

Abstract

Coal is a major contributor to various environmental issues, making the transition to alternative energy sources essential for reducing environmental impacts and combating climate change. San Juan County in New Mexico has historically depended on coal-fired power plants for producing electricity. However, due to environmental and economic pressures, there is a move to reassess energy strategies. This study explores the transition from coal to natural gas (NG) in San Juan County, with a focus on assessing changes in water usage and emissions (CO2, NOx, and SO2) at the Four Corners (coal-fired) and Afton …


Tribology Of Mos2 Thin Films Stabilized By A Chromium Underlayer And Max Phase, Nihal Ahmed Aug 2024

Tribology Of Mos2 Thin Films Stabilized By A Chromium Underlayer And Max Phase, Nihal Ahmed

Theses and Dissertations

MoS2 is a popular solid lubricant with limited application at room temperature due to its’ sensitivity to atmospheric oxygen and humidity. This thesis focuses on the stabilization of molybdenum disulfide (MoS2) coatings on aluminum substrates to enhance their tribological performance at room temperature. MoS2 exhibits exceptional lubricating properties in vacuum conditions, but its reactivity with atmospheric oxygen leads to the formation of abrasive molybdenum trioxide (MoO3), restricting its effectiveness in ambient environments. This thesis investigates the effects of a Chromium underlayer and the incorporation of MAX phase (Ti3SiC2) on the tribological performance and chemical stability of MoS2 solid lubricant. Physical …


Synthetic Data Generation For Accurate, Fair, And Private Recommender Systems, Derek B. Lilienthal Aug 2024

Synthetic Data Generation For Accurate, Fair, And Private Recommender Systems, Derek B. Lilienthal

Master's Theses

A notorious challenge for recommender systems on online platforms is to accurately and fairly recommend items that align with users’ preferences while retaining user privacy. These systems often rely on historical data that is partially labeled and includes incomplete user information, leading to the over-representation of majority groups and disproportionately favoring popular items. Substituting user data with synthetic data can address these concerns, but accurately replicating real-world datasets has been a challenging problem. Recent advancements in generative AI have demonstrated the impressive capabilities of diffusion models in generating realistic data across several domains. In this work, we introduce two variations …


Reinforcement Learning Based Planning And Control For Robotic Source Seeking Inspired By Fruit Flies, Gauravkumar Koradiya Aug 2024

Reinforcement Learning Based Planning And Control For Robotic Source Seeking Inspired By Fruit Flies, Gauravkumar Koradiya

Master's Theses

In the exploration of mobile sensing agents such as robots equipped with sensors, these agents have the potential to measure unknown scalar fields, ranging from chemical concentrations to temperature fluctuations. One of the primary interests is the robots’ ability to gravitate towards the peaks or troughs of these fields, a phenomenon termed as “source seeking”. This behavior is invaluable in practical scenarios, like detecting chemical leaks or locating survivors after catastrophes. However, the challenge becomes significantly more pronounced when operating in turbulent flow fields, where the erratic nature of odorant plumes makes predictions and simulations highly unreliable. Interestingly, fruit flies …


Controllable Physics-Informed Latent Space For Acoustic Wave Manipulation, Tristan Shah Aug 2024

Controllable Physics-Informed Latent Space For Acoustic Wave Manipulation, Tristan Shah

Master's Theses

Partial Differential Equations (PDEs) are foundational descriptive tools in scientific and engineering disciplines, enabling the exploration of phenomena from material design to climate dynamics and the propagation of pandemics and wildfires. Establishing control of PDEs, especially when the underlying phenomena are only partially observable, holds great potential for fostering technological innovations. This ambition faces considerable obstacles, as a robust sample-based solution remains elusive. Addressing this challenge, this thesis introduces a framework leveraging physics-informed machine learning (ML) to enable control of PDEs. Central to this framework is an agent, equipped with sensors to perceive its environment, that generates a low-dimensional physics-informed …


Extraction, Preparation, And Characterization Of Alginate Biopolymer Films From Natural Seaweed, David Ly Aug 2024

Extraction, Preparation, And Characterization Of Alginate Biopolymer Films From Natural Seaweed, David Ly

Master's Theses

This study evaluates the use of naturally harvested seaweed from the Monterey Bay to produce a biodegradable film for food packaging applications. Two different film-forming methods were evaluated: solution casting and compression molding. The solution casting method using an alginate biopolymer produced the most consistent results. The seaweed biopolymer was extracted from the seaweed biomass using a modified method, resulting in a yield of 11-25 %. The highest yield was observed when using the lowest biomass concentration of 10 wt. %. The extracted alginate was then cast into films at different levels of glycerol plasticization (15-35 wt.%). The addition of …


Tribological Analysis Of Heat Treatments On Medical Grade Cobalt Chromium Molybdenum Alloys, Samuel Edis Bowden Aug 2024

Tribological Analysis Of Heat Treatments On Medical Grade Cobalt Chromium Molybdenum Alloys, Samuel Edis Bowden

Theses and Dissertations

Cobalt chromium molybdenum (CoCrMo) has many material properties that make it desirable as a medical hip implant. Due to the range of heat treatments available and the resulting material properties that are present in medical device manufacturing using CoCrMo, many implants are not able to withstand both the chemical and physical wear necessary as a hip replacement. This research looks to examine various heat treatments and their resulting properties to find a desirable heat treatment for CoCrMo in hip implant bearing surfaces. This study was accomplished by using five distinct variations of heat treatment on forged CoCrMo alloy that would …


Exploring The Link Between Travel Behavior And Mental Health, Emily Kae Youngs Aug 2024

Exploring The Link Between Travel Behavior And Mental Health, Emily Kae Youngs

Theses and Dissertations

This study explores the critical link between travel behavior and mental health, focusing on young adults who have expressed suicidal ideation. By analyzing how daily activities and movement patterns impact mental well being, the research aims to explore travel related mental health approaches for individuals. The importance of this work lies in its potential to improve the quality of life for individuals by informing more personalized and effective mental health strategies. Through comprehensive data analysis and statistical modeling, the research aims to uncover insights into how travel behavior influences motivation levels and mental well-being across different neurological and physiological groups. …


Central Tracking And Billing System For Insurance Bills, Kehinde Alabi Aug 2024

Central Tracking And Billing System For Insurance Bills, Kehinde Alabi

Harrisburg University Dissertations and Theses

In this article, we introduce a new centralized billing platform designed for insurance bills including auto insurance, health insurance, home insurance, life insurance, etc. This system consolidates all bills for individual users eliminating the need for them to manage and pay bills separately. Users stand to benefit from significant time and effort savings each month, reducing the likelihood of missed payments and associated late fees. Insurance billing organizations and banks can also capitalize on timely payments and reduced physical mailings, leading to cost savings and environmental benefits. The proposed system offers users the ability to track and review their historical …


Customized Agile Project Management For Scientific Computing: Addressing Challenges And Developing A Framework, Yashesh Sakharikar Aug 2024

Customized Agile Project Management For Scientific Computing: Addressing Challenges And Developing A Framework, Yashesh Sakharikar

Harrisburg University Dissertations and Theses

This paper presents a novel Agile framework tailored for scientific computing projects. Identifying gaps in existing methodologies, the research emphasizes the need for adaptable solutions in this dynamic field. The proposed framework, characterized by flexibility and stakeholder engagement, addresses specific challenges posed by scientific computing endeavors. Through a comprehensive literature review, the paper highlights the limitations of generic Agile practices and positions the proposed framework as a valuable contribution. The study motivates further exploration into specialized Agile approaches, promising enhanced efficiency and success in scientific computing projects.


Analyzing The Usability, Performance, And Cost-Efficiency Of Deploying Ml Models On Various Cloud Computing Platforms, Hongyu Wang Aug 2024

Analyzing The Usability, Performance, And Cost-Efficiency Of Deploying Ml Models On Various Cloud Computing Platforms, Hongyu Wang

Masters Theses (Archived)

With the enhanced computing capabilities and accessibility to cloud resources, major cloud computing providers such as Google Cloud Platform (GCP), Amazon Web Services (AWS), and Microsoft Azure offer Machine Learning (ML) and AI services. Their primary purpose is to provide efficiency, scalability, and adaptability in modern software development and IT operations while reducing overall costs and operational complexity. However, prospective customers of the services often question which ML-AI service will best suit their organizational and business needs. This study compares and analyzes the usability, performance, and cost-efficiency of deploying Machine Learning (ML) models across three cloud platforms: GCP, AWS, and …


An Exploration Of Dimensionality Reduction Of Dynamics On Lie Groups Via Structure-Aware Canonical Correlation Analysis, Wooyoung Chung Aug 2024

An Exploration Of Dimensionality Reduction Of Dynamics On Lie Groups Via Structure-Aware Canonical Correlation Analysis, Wooyoung Chung

Master's Theses

Incorporating prior knowledge into a data-driven modeling problem can drastically improve performance, reliability, and generalization outside of the training sample. The stronger the structural properties, the more effective these improvements become. Manifolds are a powerful nonlinear generalization of Euclidean space for modeling finite dimensions. When additionally assuming that the manifold carries (Lie) group structure, this imposes a drastically stricter global constraint. The range of their applications is very wide and includes the important case of robotic tasks. We apply this idea to Canonical Correlation Analysis (CCA). In traditional CCA one constructs a hierarchical sequence of maximal correlations of up to …


Domain Specific Aspect Extraction For Product Design, Divyam Sobti Aug 2024

Domain Specific Aspect Extraction For Product Design, Divyam Sobti

Master's Theses

As technology advances, computers become increasingly proficient at interpreting and translating human language into machine-understandable text. With the help of algorithms in natural language processing (NLP), machines can now translate textual data. These algorithms help identify and extract specific text components known as aspects. The aspects represent specific attributes or topics within textual data. For instance, an Amazon review states,“ This phone has good battery life but poor camera quality,” and attributes like ‘battery life’ and ‘camera quality’ represent aspects in the text. Aspect extraction is a pivotal process involving identifying and isolating key features or topics within text. This …


Uas-Enhanced Rock Mass Characterization Of The Left Abutment At Madison Dam, Ennis Montana, Karl Farber Aug 2024

Uas-Enhanced Rock Mass Characterization Of The Left Abutment At Madison Dam, Ennis Montana, Karl Farber

Graduate Theses & Non-Theses

Recently, advancements in drone technology for mapping rock mass features have been on the rise and are becoming more of a staple for geotechnical site investigation. The safety of humans when collecting field data is a top priority and using drones, or unmanned aerial systems (UAS), can minimize those safety risks. Creating models that depict accurate data of rock mass discontinuities and possible failure modes in inaccessible areas has its challenges, but drones can provide a way of addressing those challenges. This study involves using UAS-based data collection to capture rock mass fractures at Madison Dam just North of Ennis, …


Engineering Cell-Free Protein Synthesis Biosensors For Point Of Care Use, Tyler Jordan Free Aug 2024

Engineering Cell-Free Protein Synthesis Biosensors For Point Of Care Use, Tyler Jordan Free

Theses and Dissertations

Diagnostic tests can dramatically improve and save lives. Survival rates and patient outcomes related to cancer and other diseases can be improved when routine testing guides personalized treatment. Highly accurate laboratory tests exist for thousands of biomarkers, including those of interest in this dissertation, but cost and complexity limit access to life-saving lab tests in many cases throughout the world. To fill this need and increase accessibility of diagnostics, in this report we report our engineering advancements towards portable biosensors for colorimetric detection of glutamine, endocrine disrupting compounds (EDC), and pathogenic RNA which are key biomarkers in cancer treatment monitoring, …


A Comparative Illustration Of Trip- And Activity-Based Modeling Techniques, Steven Hayden Atchley Aug 2024

A Comparative Illustration Of Trip- And Activity-Based Modeling Techniques, Steven Hayden Atchley

Theses and Dissertations

Activity-based travel demand models are generally considered superior to their trip-based counterparts, as activity-based models (ABMs) explicitly model individuals in contrast to the aggregate nature of trip-based models. There have been a number of comparisons between trip- and activity-based models, but these comparisons focus almost exclusively on the technical ability of the two model types, while not considering the practical benefits an ABM may or may not have to a transportation agency. This research performs a more holistic comparison between trip- and activity-based models, focused specifically on the practical differences between model types, both in terms of usability and capability …


Integrated Reference Single-Cell Rna Seq Atlas Of Healthy Human Female Tissues To Expand The Computational Drug Target Discovery Approaches For Female-Directed Non-Hormonal Contraceptives, Zhanel Nugmanova Aug 2024

Integrated Reference Single-Cell Rna Seq Atlas Of Healthy Human Female Tissues To Expand The Computational Drug Target Discovery Approaches For Female-Directed Non-Hormonal Contraceptives, Zhanel Nugmanova

Dartmouth College Master’s Theses

The ovary is vital for fertility and the maintenance of endocrine homeostasis. It contains heterogeneous cell populations, including oocyte, granulosa, stromal, endothelial, smooth muscle, and immune cell types. Creating a harmonized dataset that enables cross-tissue comparisons, including the ovary, is essential for identifying genes specific to ovarian cell types and for facilitating drug discovery for contraception and fertility purposes. There are very few resources that allow for the assessment of the expression of potential gene targets across human and mouse tissues for female-directed non-hormonal contraceptives. This is because most of these publicly available datasets are from post-menopausal women. Through our …


Deep Learning For Improved Data-Driven Modeling Of Soft Robots For Model Predictive Control, Daniel Gray Cheney Aug 2024

Deep Learning For Improved Data-Driven Modeling Of Soft Robots For Model Predictive Control, Daniel Gray Cheney

Theses and Dissertations

The field of soft robotics is a growing research interest due to the unique benefits of soft robots over traditional robots, such as durability, compliance, and low-cost. These benefits allow soft robots to perform a variety of tasks that would be difficult for traditional robots, such as throwing, hammering, or whole-body manipulation. However, there is a significant variety of materials, actuators, and designs used in soft robotics. While helpful for completing more tasks, this variety also makes efficient modeling and control of soft robots difficult. In this thesis, an open-source repository, Modeling for Learned Dynamics (MoLDy), is presented. This repository …


Proposing A Matrix For Selecting Security Tools For Small Businesses, Nathan Jonathon Rowbotham Aug 2024

Proposing A Matrix For Selecting Security Tools For Small Businesses, Nathan Jonathon Rowbotham

Theses and Dissertations

Small businesses are increasingly under threat of cybersecurity attacks. An increasingly long list of tools with different purposes and coverage are available to help. But it can be difficult to choose which tools to use, particularly for a small business that may lack financial resources, expertise, and time. Research literature focuses on providing frameworks to follow to protect a business generally. Some research considers an aspect of creating a Security Operations Center. Other research describes the creation of a Security Operations Center as a Service with all the components the researchers deemed necessary. None of the current research literature seems …


Real-Time Dynamically Feasible B-Spline Trajectory Generation For Unmanned Aircraft, David Lavae Christensen Aug 2024

Real-Time Dynamically Feasible B-Spline Trajectory Generation For Unmanned Aircraft, David Lavae Christensen

Theses and Dissertations

Onboard aircraft systems must frequently plan dynamically feasible paths or trajectories to safely and quickly reach their goal position. Optimized B-splines are promising because they can guarantee kinematic feasibility in a computationally efficient manner and can be applied to a variety of vehicle models. However, current B-spline solutions do not adequately constrain trajectories to the physical limitation of the vehicles they are planning for, or are often too conservative. Most are also limited to path smoothing or require pre-optimized timing parameters. This thesis develops a real-time B-spline optimization-based trajectory generator capable of minimizing time while respecting the velocity, acceleration, and …