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Full-Text Articles in Engineering

Mobile Air Quality Assessment Using Public Transportation: A Community-Focused Study In The Capital Region, Allen Pronith Reddy Yeddula Jan 2025

Mobile Air Quality Assessment Using Public Transportation: A Community-Focused Study In The Capital Region, Allen Pronith Reddy Yeddula

Electronic Theses & Dissertations (2024 - present)

The monitoring of air quality plays a crucial role in establishment of concentrations of air pollutants over space and time in relation to human health, urban planning, and environmental conservation. This research offers a new strategy of monitoring the air quality in the Capital Region of New York State utilizing public transit buses as air quality moving sampling platforms. To assess the level of pollutants, a Capital District Transportation Authority (CDTA) bus network was used across the urban, suburban, and rural areas thus filling a research gap where public transit has most of the time been disregarded as a mobile …


Investigation Of Electromigration Stresses Of Advanced Node Conductors Through Pulsed Power Behavior, Mohd Mueen Ul Islam Mattoo Jan 2025

Investigation Of Electromigration Stresses Of Advanced Node Conductors Through Pulsed Power Behavior, Mohd Mueen Ul Islam Mattoo

Electronic Theses & Dissertations (2024 - present)

The microelectronics industry continues to put a heavy focus on preventing electromigration (EM) failures at advanced node conductors. The continuous scaling coupled with higher operating current densities further accentuate the problem. Most of the electromigration testing in the industry is performed with DC currents to evaluate the electromigration reliability of metal interconnects. However, most of the real-world applications operate using a pulsed current rather than a constant direct current. EM testing with pulsed direct current (PDC) show interesting results with how the current induced stress gradient evolves in absence of the electromigration driving force. It is generally assumed that the …


Innovative Biomechanical And Engineering-Based Assessments Of Hip Mechanics In Individuals With Hip-Related Pain, Holly M. Stanze Jan 2025

Innovative Biomechanical And Engineering-Based Assessments Of Hip Mechanics In Individuals With Hip-Related Pain, Holly M. Stanze

Theses and Dissertations--Kinesiology and Health Promotion

Individuals with hip-related pain exhibit altered movement patterns, and worse fear of movement (kinesiophobia), compared to asymptomatic controls. Exacerbation of hip pain during movement and the role of hip symptom duration may help further our understanding of specific movement patterns that are associated with hip-related pain. A better understanding of the potential connections between hip-related symptom duration, kinesiophobia, hip pain during movement, and lower limb mechanics in those with hip-related pain may allow for more efficient referrals to clinicians and lead to more effective rehabilitation. In addition, the impact of hip-related pain on intra-articular hip loading patterns is not well …


Investigation Of Subsurface Thermal Radiation Phenomena In Fibrous Thermal Protection Systems, Colby L. Gore Jan 2025

Investigation Of Subsurface Thermal Radiation Phenomena In Fibrous Thermal Protection Systems, Colby L. Gore

Theses and Dissertations--Science, Technology, Engineering, and Mathematics (STEM) Education

Atmospheric re-entry induces intense thermal stress upon vehicles through a high-enthalpy boundary layer that encompasses the craft. To protect these vehicles, numerous insulative methods, known as thermal protection systems (TPS), are deployed to protect the craft during re-entry. The TPS materials insulate the craft from intense thermal transmission that would terminate a mission. In hypersonic environments, vast temperature gradients exist, enforcing the exponential effect of thermal radiation. However, TPS materials are commonly low-density fibrous materials that allow for the potential to be penetrated by thermal radiation. A series of arc-jet tests was completed to replicate enhanced radiative conditions in a …


Leaning Pine Arboretum Gazebo, Carson C. Henry Jan 2025

Leaning Pine Arboretum Gazebo, Carson C. Henry

Construction Management

The Leaning Pine Arboretum gazebo provides an aesthetic relaxation space for visitors to the arboretum as well as being a functional structure for faculty as a future event space. This gazebo replaces an existing one, revitalizing the space in conjunction with the arboretum’s planned growth over the coming years. There were many challenges throughout the construction process including permitting issues, design complexities, and coordination with architects and engineers. Persevering through these taught a great deal about project management, the construction industry, and the importance of teamwork. The structure is a total rejuvenation of the prior structure; it is now stronger, …


Developing A 4d Logistics Educational Module With Cmbuilder, Misael Gonzalez Ramirez Jan 2025

Developing A 4d Logistics Educational Module With Cmbuilder, Misael Gonzalez Ramirez

Construction Management

The increasing adoption of Building Information Modeling (BIM) in the construction industry has led to a need for its increasing integration into construction management education. While existing curriculum covers various BIM applications, there is often a gap in in-depth instruction on BIM-based site logistics planning. This paper details the development of an educational module designed to address this gap, focusing on 4D site logistics and phasing using cmBuilder. The module aims not only to provide students with technical software skills but also to equip them with practical skills in visualizing, planning, and communicating complex construction site logistics. Through a series …


Statistical Investigation Of Gypsum Crystallization Kinetics, Azmain A. Akash Jan 2025

Statistical Investigation Of Gypsum Crystallization Kinetics, Azmain A. Akash

LSU Master's Theses

Gypsum, a naturally occurring mineral salt, is frequently encountered in industrial processes such as seawater desalination and power plant cooling. Over the years, significant effort has been devoted to controlling the crystallization of gypsum through various chemical approaches, including acidification, chelating agents, and antiscalant polymers. Nevertheless, the cost associated with chemical treatments may be reduced by incorporating physical operational strategies to complement chemical methods in regulating gypsum crystallization.

This study systematically examines the comparative roles of chemical and physical entropy in the gypsum crystallization process to elucidate their respective influences on gypsum growth kinetics. Chemical entropy is manipulated by adjusting …


Investigation Of Under-Frequency Load Shedding Prevention Of Isolated Medium-Sized Power Systems Using Energy Storage, Dilan Indoopa Manamperi Jan 2025

Investigation Of Under-Frequency Load Shedding Prevention Of Isolated Medium-Sized Power Systems Using Energy Storage, Dilan Indoopa Manamperi

Theses: Doctorates and Masters

Due to the rapid uptake of distributed photovoltaic generation, the visible load to transmission operators in distribution feeders is reducing. Traditional load-shedding schemes are facing challenges due to this low-load situation. The required amount of load reduction cannot be achieved with the same load-shedding scheme as before. In some situations, with reverse power flows, load shedding can further increase the generation reduction. On the other hand, increased Rate of Change of Frequency (RoCoF) due to low inertia can result in false activation of under-frequency load shedding (UFLS) relays. These challenges can cause a serious problem with the power system security. …


The Effect Of Huntington’S Disease On The Mechanical And Electrical Properties Of Red Blood Cells, Liliana Ponkratova Jan 2025

The Effect Of Huntington’S Disease On The Mechanical And Electrical Properties Of Red Blood Cells, Liliana Ponkratova

Electronic Theses and Dissertations 2020 - Present

Huntington’s disease (HD) has an impact on brain tissues and can alter the biochemical properties of the peripheral blood. Evidence in existing literature suggests that peripheral mutant Huntingtin protein may be involved and deteriorate HD. Red blood cells (RBCs), being the most abundant type of cells in the peripheral blood, can show detectable changes in their biophysical properties due to subtle changes in cell membranes. These changes can offer a minimally invasive means to track the progression of the disease. The transgenic line R6/2 is used as the disease model. Utilizing the electro-deformation spectroscopy, we measured membrane permittivity, cytoplasm conductivity, …


Movie Genre Classification Using Script Texts, Michael Roman Cuomo Jan 2025

Movie Genre Classification Using Script Texts, Michael Roman Cuomo

Electronic Theses and Dissertations 2020 - Present

Genres are used to classify movies so that they can be grouped with others that have similar themes and structures. These classifications are categories created by humans. In the process of creating a movie, a script is often the first creation to write and share ideas about a topic. The script contains large amounts of text that is used to describe the dialog, setting and direction of the film. Although the script contains important information for the film, the amount of text can present a challenge for machine learning algorithms. Often in studies on film classification, if text is used, …


Groundwater Pumping Impacts On Stream Depletion In Humboldt County, Ca: Integrating Analytical Models And Field Data, Andy Hans Heise Jan 2025

Groundwater Pumping Impacts On Stream Depletion In Humboldt County, Ca: Integrating Analytical Models And Field Data, Andy Hans Heise

Cal Poly Humboldt theses and projects

This study addresses the significant concern of stream depletion from groundwater pumping in Humboldt County, CA. The objective of this study is to develop an analytical model for estimating stream depletion and integrating field data into model parameters.

The methodology involved conducting a field study near three operating wells by a stream, installing stream gages upstream and downstream of the wells, and recording pumping rates and schedules for two of the wells. The third well’s pumping data was synthetically generated, for privacy concerns of the well owner. The StreamDepletR package was used for estimating depletion rates in a stream in …


From Spark To Wildfire: Predicting Wildfire Origins And The Efficacy Of “Fire Safe” Cigarettes In California Grasslands, Trevor Blackwell Haltermann Jan 2025

From Spark To Wildfire: Predicting Wildfire Origins And The Efficacy Of “Fire Safe” Cigarettes In California Grasslands, Trevor Blackwell Haltermann

Cal Poly Humboldt theses and projects

As wildfires in North America increase in size and frequency, the societal impacts become greater as well. With greater risk and high fire suppression costs it is pertinent to improve fire investigation methods and limit the potential for human caused ignitions. Two distinct studies were carried out to assess the accuracy of fire pattern indicators and the efficacy of “fire safe” cigarette technology in lowland grass fuel types in California. The first study utilized 24 experimental small-scale fires within a wind tunnel to examine the accuracy of microscale fire pattern indicators and the factors that influence the accuracy of predictions …


An Analysis Of Uv Disinfection Of Municipal Wastewater Following Natural Treatment Systems, Jonathan Andrew Kirchubel Jan 2025

An Analysis Of Uv Disinfection Of Municipal Wastewater Following Natural Treatment Systems, Jonathan Andrew Kirchubel

Cal Poly Humboldt theses and projects

On January 30, 2024, the City of Arcata replaced chlorine with ultraviolet (UV) irradiation as its disinfection method for treating its wastewater prior to discharging to Humboldt Bay. The Arcata wastewater treatment facility (AWTF) utilizes natural treatment systems for treating its secondary effluent, which can provide issues for UV disinfection through variance in turbidity, total suspended solids (TSS), pH, humic acids, and color. This project aimed to identify whether the water quality characteristics of natural treatment systems in the AWTF would impact UV disinfection of municipal wastewater.

Thirty-one sampling periods occurred between June 8, 2024, and March 1, 2025, recording …


First-Principles Study Of Ferroelectric Properties And Co2 Reduction Reaction Capabilities In Two-Dimensional Monolayers And Heterostructures, Mo Li Dec 2024

First-Principles Study Of Ferroelectric Properties And Co2 Reduction Reaction Capabilities In Two-Dimensional Monolayers And Heterostructures, Mo Li

Dissertations

Two-dimensional (2D) materials hold significant potential for CO2 reduction reactions (CO2RR) due to their high surface-to-volume ratio. However, achieving high selectivity for desired products and overcoming limitations posed by scaling relationships remain challenging. Recent studies suggest that ferroelectric (FE) materials with switchable out-of-plane polarization (OOP) can effectively tune the adsorption behavior, thermodynamics, and kinetics of CO2RR, offering promising solutions to these challenges. Using density functional theory (DFT) and the Berry phase approach, this work expands the family of 2D ferroelectrics by theoretically identifying Y2CO2, Y2CS2, and Sc …


Determination Of Electrochemical Parameters For Predicting Reaction Mechanism And Algorithmic Approaches To Pain Assessment, Huize Xue Dec 2024

Determination Of Electrochemical Parameters For Predicting Reaction Mechanism And Algorithmic Approaches To Pain Assessment, Huize Xue

Dissertations

This dissertation introduces novel advancements in electrochemical kinetics and pain assessment, structured into two main parts. The first part focuses on the comprehensive analysis of the kinetic and mechanistic aspects of electrochemical reactions, utilizing a combination of experimental techniques and simulation methods. A new software tool, Envismetrics, was developed using Python to facilitate the analysis of complex electrochemical data, including cyclic voltammetry (CV), chronoamperometry (CA), and hydrodynamic voltammetry (HDV). The software was rigorously tested and validated with well-characterized redox systems such as the ferricyanide/ferrocyanide couple, dimethylamine borane (DMAB), and Per- and Polyfluoroalkyl Substances (PFAS). It was successfully used to determine …


Gas-Generating Reactive Materials: Design, Evaluation And Effect Of Morphology On Their Ignition And Combustion, Purvam Mehulkumar Gandhi Dec 2024

Gas-Generating Reactive Materials: Design, Evaluation And Effect Of Morphology On Their Ignition And Combustion, Purvam Mehulkumar Gandhi

Dissertations

This work investigates optimizing gas-generating reactive materials, focusing on particle morphology's effect on ignition and combustion behavior. Metal-based gas-generating energetic materials (EMs) are promising alternatives to replace traditional CHNO compounds. Design of advanced metal-based EMs requires consistent ways of evaluating how their characteristics affect their ignition and combustion. Many relevant evaluation approaches exist; however, the results may be difficult to compare directly across different studies. Commonly, experimentalists ignite metal-based EMs in enclosed chambers and report pressures, P. However, direct comparison of these pressures is hindered by variations in the chamber volume, V, and the EM mass, m. To standardize the …


Decomposition Of Diisopropyl Methylphosphonate (Dimp) Exposed To Elevated Temperatures And Combustion Products Of Reactive Materials, Elif Irem Senyurt Dec 2024

Decomposition Of Diisopropyl Methylphosphonate (Dimp) Exposed To Elevated Temperatures And Combustion Products Of Reactive Materials, Elif Irem Senyurt

Dissertations

The safe and efficient destruction of chemical weapon agents (CWAs) stockpiles remains a critical global challenge. Understanding the thermophysical properties, decomposition mechanisms, and interactions of CWAs with their environment is crucial for developing effective strategies to mitigate their threats. Diisopropyl methylphosphonate (DIMP) and Dimethyl methylphosphonate are commonly used nerve agent surrogates. This dissertation focuses on DIMP and DMMP, investigates their properties and behavior under conditions relevant to prompt defeat scenarios.

The thermophysical properties of DIMP and DMMP were experimentally characterized, including vapor-liquid surface tension (3-60 °C) and viscosities of neat and aqueous solutions. Results revealed significant non-ideal behavior in aqueous …


Developing A Roadmap For Green Port In Timor-Leste, Emanuel Da Silva Maia Dec 2024

Developing A Roadmap For Green Port In Timor-Leste, Emanuel Da Silva Maia

World Maritime University Dissertations

No abstract provided.


Exploration Of The Iterative Design Process: Integrating A Requirements Matrix And Hazard Analysis Toolsexploration Of The Iterative Design Process: Integrating A Requirements Matrix And Hazard Analysis Tools, Blaine Edlefsen Dec 2024

Exploration Of The Iterative Design Process: Integrating A Requirements Matrix And Hazard Analysis Toolsexploration Of The Iterative Design Process: Integrating A Requirements Matrix And Hazard Analysis Tools, Blaine Edlefsen

Theses

The iterative design process is applied to multiple industry sectors from software development to product manufacturing. The cyclical approach integrates the steps of design, prototyping, and testing toward the realization of a user's specified needs. The use of a requirements traceability matrix and hazard analysis documentation that supports the definition of the iterative design process is explored. These design project management tools are applied to a case study involving workholding design for a Wire Electrical Discharge Machining (Wire-EDM) manufacturing process. This industry-relevant case study is conducted in collaboration with New Jersey Precision Technologies, Incorporated (NJPT). The design requirements involve both …


Automated Segmentation Of The Ulnar Nerve In Mri Using Deep Learning Techniques, Akhil Nagulapalli Dec 2024

Automated Segmentation Of The Ulnar Nerve In Mri Using Deep Learning Techniques, Akhil Nagulapalli

Theses

Cubital Tunnel Syndrome (CuTS), a condition caused by compression of the ulnar nerve, results in numbness, tingling, pain, and even muscle atrophy, affecting fine motor skills and diminishing patient quality of life. Accurate diagnosis of CuTS is challenging, as current diagnostic methods—including clinical exams, nerve conduction studies, and unaided MRI—often lack the precision to reliably identify the nerve and detect compression in its early stages. Deep learning-based segmentation offers a promising solution, enabling precise and automated identification of nerve structures in MRI images, which could significantly improve diagnostic accuracy and support timely intervention.

A novel deep learning model for segmenting …


Metakaolin-Based Geopolymer Concrete; Synthesis, Development And Characterization, Heba Fouad Dec 2024

Metakaolin-Based Geopolymer Concrete; Synthesis, Development And Characterization, Heba Fouad

Theses and Dissertations

Geopolymers are rendered as an essential sustainable replacement to the widely used Ordinary Portland Cement (OPC) which causes immense carbon dioxide emissions, hence a detrimental impact on society’s health and the environment. Geopolymers are three-dimensional networks of polymerized tetrahedral silicate and aluminate in the form of Q4(4Al), Q4(3Al) and Q4(2Al) which act as the principal binding phase in concrete. Past research has reported the synthesis of geopolymers from different aluminosilicates precursors, their characterization, and their wide range properties. However, previous studies still have not properly investigated effective range of synthesis ratios for a particular source material, optimum curing regimes, short- …


Experimental Insights Into Friction Losses Of Post-Tensioned Precast Full-Scale Girders, Mostafa Serry Dec 2024

Experimental Insights Into Friction Losses Of Post-Tensioned Precast Full-Scale Girders, Mostafa Serry

Theses and Dissertations

The use of post-tensioning in construction has revolutionized the construction industry and made way for several construction and structural applications that were unattainable before. One of the most important topics that are synonymous with the use of post-tensioning is the matter of accurately calculating the short-term and long-term losses that arise in pre-stress. One of the prominent types of losses is the friction losses that occur during the jacking of the concrete elements due to its impact on structural integrity and longevity.

The thesis examines this critical aspect of friction losses in post-tensioned concrete structures. The study focuses on full-scale, …


A Comparative Study Between Soft Structures And Hard Structures For The Protection Of Egypt’S Coastlines Against Climate Change, Donia Eldwib Dec 2024

A Comparative Study Between Soft Structures And Hard Structures For The Protection Of Egypt’S Coastlines Against Climate Change, Donia Eldwib

Theses and Dissertations

Coastal communities worldwide face unprecedented threats from climate change, with rising sea levels, increased storm intensities, and accelerated coastal erosion posing significant risks. Egypt, with over 3,000 kilometers of coastlines along the Mediterranean and Red Seas, it is particularly vulnerable due to its densely populated and economically critical low-elevated coastal zones. With the Mediterranean Sea, and the Nile Delta specifically under huge threats, this study examines the different coastal protection strategies used to address these climate change impacts. Different coastal protection structures have been used throughout the years starting with the well-known hard structures moving on to greener alternatives such …


End-To-End Autonomous Quadcopter Using Reinforcement Learning, Mohamed Marwan Chawa Dec 2024

End-To-End Autonomous Quadcopter Using Reinforcement Learning, Mohamed Marwan Chawa

Theses and Dissertations

This thesis investigates the potential of Reinforcement Learning (RL) for achieving robust and adaptable quadcopter control, focusing on trajectory and attitude stabilization. We compare state-of-the-art RL algorithms, specifically Proximal Policy Optimization (PPO), against traditional Proportional-Integral-Derivative (PID) controllers across three tasks: hovering, slow trajectory following, and fast trajectory following. To enhance realism, we employ a modified PyFlyt simulation environment with a high-fidelity Crazyflie 2.x model, accounting for motor dynamics, noise, wind disturbances, and aerodynamic drag.

The challenge of operating a quadcopter can be divided into two distinct parts: planning a flight path and actually following that path. Our focus is on …


Physics-Informed Heterogeneous Spatiotemporal Graph Neural Network For Reservoir Simulation, Ahmed A.M.A. Abdullah Dec 2024

Physics-Informed Heterogeneous Spatiotemporal Graph Neural Network For Reservoir Simulation, Ahmed A.M.A. Abdullah

LSU Master's Theses

Reservoir simulation is the state-of-the-art method for predicting the flow of petroleum reservoir fluids in porous media. It provides an accurate and unbiased prediction of the performance of petroleum reservoirs under different operating conditions. Despite its advantages, reservoir simulation is computationally expensive; with typical full-field simulation models running for several hours. This limitation is worsened when simulating reservoirs with several equations for each cell, such as multiphysics or compositional reservoir simulation. The goal of this research is to provide a fast and accurate spatiotemporal machine-learning model that incorporates discretized governing mass balance equations for training. To achieve this, we propose …


Measuring And Improving Api Usability And Quality: A Comprehensive Framework And Empirical Study, Sultan Alanazy Dec 2024

Measuring And Improving Api Usability And Quality: A Comprehensive Framework And Empirical Study, Sultan Alanazy

Computer Science and Engineering Theses and Dissertations

Cloud computing provides on-demand access to flexible computing resources, enabling rapid application deployment without substantial infrastructure investment. Application Programming Interfaces (APIs) play an important role in ensuring the success of cloud applications. The primary users of APIs are the extensive community of application programmers who search, read, and understand APIs before integrating them into their applications or systems. In addition, developers often turn to online API support when seeking help. Problems in such support can result in incorrect API usage and integration problems. There is an urgent need to measure API usability and support issues to identify, characterize, and assess …


Microwell Fabrication For Impedance And Ac Measurements Of Isolated Ventricular Cardiomyocytes, Fallon Wenck Dec 2024

Microwell Fabrication For Impedance And Ac Measurements Of Isolated Ventricular Cardiomyocytes, Fallon Wenck

Multidisciplinary Studies Theses and Dissertations

Electrophysiological behavior of human hearts have been extensively studied for hundreds of years. Even with elucidation of not just biological function, but also time and frequency-dependent current flow, the sheer intricacy of in vivo cardiac tissue function remains somewhat enigmatic. All while heart disease has been the leading cause of death in the United States for over a century, with its rates of occurrence still increasing annually [1]. Thus, new research techniques and tools to quantify cardiac function are still being pursued at smaller and smaller scales to decrease research/innovation time, cost, and diagnostic ambiguity. In fact, it remains incredibly …


A Comparison Of Polymers By Layer Deposition And Open Molding Additive Processes Through Fused Granulate Fabrication, Alexander Ray Gibson Dec 2024

A Comparison Of Polymers By Layer Deposition And Open Molding Additive Processes Through Fused Granulate Fabrication, Alexander Ray Gibson

Theses and Dissertations

Additive manufacturing (AM) continues to offer new possibilities in both production and economics. Various industries have quickly adopted AM to rapidly produce parts that would be difficult or cost prohibitive otherwise. Despite ongoing innovations that expand the technology's capabilities, significant limitations persist. Most AM processes are restricted by materials available, an inability to produce large parts, or by not achieving material deposition speeds and volumes to allow for certain products feasible. In addition, tight tolerances for features and surfaces cannot be produced without substantial post processing. Some of the post-processing techniques can even affect the material properties of the finished …


Enhancing Concrete Sustainability With Self-Healing Technologies, Al Shimaa Abdullatif Dec 2024

Enhancing Concrete Sustainability With Self-Healing Technologies, Al Shimaa Abdullatif

Theses and Dissertations

Thanks to its strength, durability and affordability, Portland cement concrete is the most commonly used building material worldwide. However, concrete cracking is inevitable due to numerous factors including shrinkage, exposure to external chemicals, internals reactions, excessive loads, to name but a few. Self-healing is a promising technique that can enable concrete to autogenously heal cracks and alleviate much of the damage. Such healing can without a doubt extend the service life with less need for external repair works therefore it contributes to sustainability. Over the years, several means of self-healing agents have been explored including bio-based procedures and the incorporation …


A Systematic Approach To Vehicle Suspension Modeling: Integrating Experimental Testing And Simulation-Based Validation, Naoufel Ghannami Dec 2024

A Systematic Approach To Vehicle Suspension Modeling: Integrating Experimental Testing And Simulation-Based Validation, Naoufel Ghannami

Honors Theses

This thesis explores the dynamic behavior of suspension systems using a radio-controlled (RC) vehicle as the study unit. By combining experimental drop testing and the Mississippi State Autonomous Vehicle Simulator (MAVS), the research focuses on determining key suspension parameters, including the spring constant and damping coefficient, which define the stiffness and energy dissipation characteristics of the system. The RC vehicle's suspension system provided a controlled platform for studying these dynamics under both real-world and simulated conditions. Experimental drop testing involved capturing the vehicle's response to impact using an accelerometer, while MAVS simulations modeled a controlled compression and release of the …