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Full-Text Articles in Engineering

Economic Impact Considerations For Sustainable Design Engineering As Derived From The Literature, K. Joshua Kelley, Christopher A. Mattson, Nile Hatch, John L. Salmon Aug 2024

Economic Impact Considerations For Sustainable Design Engineering As Derived From The Literature, K. Joshua Kelley, Christopher A. Mattson, Nile Hatch, John L. Salmon

Undergraduate Honors Theses

This thesis contributes to the scholarship on sustainable development by presenting a review of the literature on the economic impacts of engineering design decisions and engineered products. Many design engineers already consider the economic impacts of their work, especially those impacts related to production cost and the economic feasibility of their products. However, we believe that a review of our findings can help design engineers consider a more comprehensive set of economic impacts that apply to their work, leading to greater sustainability. Presented in this thesis are 11 economic impact categories, spanning three economic scopes.


Detecting Sand Ingress And Migration Using Fiber Optic Distributed Acoustic Sensing Technology And Computational Fluid Dynamics During Oil And Gas Production, Rishikesh Shetty Aug 2024

Detecting Sand Ingress And Migration Using Fiber Optic Distributed Acoustic Sensing Technology And Computational Fluid Dynamics During Oil And Gas Production, Rishikesh Shetty

LSU Doctoral Dissertations

Sand production in oil and gas operations presents significant challenges, leading to equipment damage, reduced production efficiency, and costly well interventions. Conventional sand detection techniques, primarily surface-based acoustic sensors, fail to provide real-time insights into sand ingress and migration within the wellbore. This dissertation explores the use of distributed fiber optic sensing technology for monitoring sand transport in pipelines and wellbores.

This research is divided into two experimental phases: a surface flow loop and a wellbore setup. The surface flow loop experiment involves a 40-ft-long, 2-in. diameter PVC pipe to simulate sand transport in horizontal pipelines. Sand slurry, with varying …


Sources And Transport Of Dissolved Organic Carbon In Barataria Basin, Louisiana, Mukseet Mahmood Aug 2024

Sources And Transport Of Dissolved Organic Carbon In Barataria Basin, Louisiana, Mukseet Mahmood

LSU Master's Theses

The fate of soil organic carbon loss from eroding coastal wetlands is of great importance, given its potential impact on atmospheric CO2 concentration. A large fraction of this soil organic carbon upon coastal erosion is released as dissolved organic and inorganic carbon (DOC and DIC) to adjacent water bodies.

In this study, we investigate the seasonal distribution and transport of DOC and DIC in Barataria basin in Louisiana, USA, bordering northern Gulf of Mexico. This region is currently undergoing one of the highest land-loss in the USA. Seasonal measurements of DOC, DIC and colored dissolved organic matter (CDOM) were carried …


Real Time Pii Scanning, John David Aug 2024

Real Time Pii Scanning, John David

Electronic Theses and Dissertations

The increased amount of web applications and internet software solutions utilizing cloud frameworks has contributed to large data sets of system log messages being generated constantly. These messages may contain sensitive data, creating an additional security risk for the systems and contributing to the need for analysis of such large volumes of data in real time. Large commercial data monitoring systems can solve for these analysis requirements, but they can be costly. We present a solution to analyzing web application log data which ingests it, processes it and visualizes sensitive data found within in real time. Our solution utilizes an …


Heterogeneous Multi-Robot Person-Following In Constrained Environments, Ori A. Miller Aug 2024

Heterogeneous Multi-Robot Person-Following In Constrained Environments, Ori A. Miller

Electronic Theses and Dissertations

Maintaining visibility of a person requires effective systems. Security cameras or ground robots might be ideal, but they often fail in uncontrolled or unknown environments. A single ground robot struggles to navigate and track an agent at the same time. This work addresses the challenge by developing a multi-robot system with a slow ground robot and an agile aerial robot. Three methods are evaluated: FORWARD-PF, RL-Person Following (RL), and a baseline closed-loop method. FORWARD-PF proved the most reliable, completing all nine paths and reaching targets nearly twice as fast as RL. Despite completing seven paths, RL faltered on complex tasks. …


Koopman-Based Modeling For Nonlinear Control Of Multirotor Uavs, Simone Martini Aug 2024

Koopman-Based Modeling For Nonlinear Control Of Multirotor Uavs, Simone Martini

Electronic Theses and Dissertations

This PhD dissertation focuses on adopting the emerging Koopman Operator theory for modeling and nonlinear control of multirotor UAVs, focusing specifically on quadrotors for proof-of-concept demonstration purposes.

The Koopman Operator theory is based on the foundation that nonlinear dynamics in the state space may be represented as a linear evolution of some functions in the state space. Thus, using appropriately defined and possibly nonlinear functions of the state variables, called observables, as a new and maybe infinite set of coordinates that are referred to as lifted space, the original nonlinear dynamics appear to be linear. The implications of this theory …


Integrating Authentication Schemes In Augmented And Virtual Reality Classrooms, Naheem Noah Aug 2024

Integrating Authentication Schemes In Augmented And Virtual Reality Classrooms, Naheem Noah

Electronic Theses and Dissertations

Augmented Reality and Virtual Reality (AR/VR) technologies are revolutionizing educational experiences, but their widespread adoption hinges on addressing critical security and usability challenges, particularly in the domain of user authentication. This research presents an investigation into the security landscape of AR/VR and explores a graphical authentication scheme called “Things” that enhances both security and usability in immersive learning environments. Through a systematic evaluation of popular AR/VR devices and applications, potential vulnerabilities and limitations were identified, such as high usage of pin/passwords which are susceptible to shoulder-surfing attacks, lack of multi-factor authentication, and unclear data-sharing practices. A review of existing knowledge-based …


Advancing Electrochemical Microsensors For Multiplexed Neurotransmitters And Environmental Toxins Detection, Sanjeev Billa Aug 2024

Advancing Electrochemical Microsensors For Multiplexed Neurotransmitters And Environmental Toxins Detection, Sanjeev Billa

Doctoral Dissertations

Electrochemical sensors have emerged as a promising solution for monitoring neurotransmitters and heavy metals, which could ensure good health and safety in the environment. This dissertation focuses on advancement in the field of electrochemical microsensors by improving the electrode properties and sensor metrics such as rapid response time, multiplexing, high sensitivity, high selectivity, and accuracy for the real-time monitoring of neurotransmitters (glutamate and GABA) and heavy metals (cadmium and lead). In this dissertation, a novel silicon (Si) multifunctional biosensor probe with four platinum ultramicroelectrodes (UMEs) and an on-demand in situ calibration (ODIC) microfluidic channel was optimized for sub-second simultaneous real-time …


Micropatterning Of Biologically Derived Surfaces With Functional Clay Nanotubes, Nisha Lama Aug 2024

Micropatterning Of Biologically Derived Surfaces With Functional Clay Nanotubes, Nisha Lama

Doctoral Dissertations

In this study, we have generalized an assembly of 50 nm diameter clay nanotubes on larger 20-50 μm diameter biological microfibers such as human hair (protein), cotton (cellulose) and synthetic polyethylene terephthalate- PET. We developed a common set of parameters and nanoclay coating techniques on these naturally different microfibers. We exploited and optimized the electrostatic interaction of the components through strategic adjustments in the solvent pH, employing polycation treatment, as well as selectively modifying the halloysite nanotubes with silanes. For 5 mins, a 5 wt% aqueous dispersion of halloysite nanotubes were applied to get approximately 1-2 μm thick fiber coating …


Robotic Odor Source Localization Using Vision And Olfaction Sensing, Sunzid Hassan Aug 2024

Robotic Odor Source Localization Using Vision And Olfaction Sensing, Sunzid Hassan

Master's Theses

Robotic Odor Source Localization (ROSL) technology allows autonomous agents like robots to find an odor source in unknown environments. A successful odor source location depends crucially on an effective navigation algorithm that directs the robot towards the odor source. This thesis is a combination of three projects. First, we detail development of a versatile multi-modal robotic platform for ROSL real-world ROSL experimentation and discussed real-world validation of a traditional olfactionbased ROSL algorithm. Secondly, we introduced vision in ROSL by proposing a fusion navigation algorithm that integrates deep-learning enabled vision and olfaction-based navigation. This hybrid approach tackles challenges such as turbulent …


Optogenetic Control Of Bacterial Dormancy, Yousr Dhaouadi Khattab Aug 2024

Optogenetic Control Of Bacterial Dormancy, Yousr Dhaouadi Khattab

Dissertations - ALL

The presence of persister cells makes it difficult to eradicate chronic bacterial infections as these dormant subpopulations arise with exposure to stressors and are capable of surviving antimicrobials that target active cells. Persisters can also revert back to normal growing cells when stressors are removed thus reestablishing the infection. It is therefore important to understand the underlying mechanisms of persister formation, as well as wake-up, and target these systems in order to treat chronic bacterial infections. The formation of persisters, however, remains elusive as there is not yet a clear relationship between the various stages of dormancy. Persister cells can …


Contributions To The Understanding Of Turbulent Boundary Layers Over Curved Walls, Nicholas Zhu Aug 2024

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 …


Analysis Of Traffic Operation And Safety At Cloverleaf And Diamond Interchanges With And Without Connected And Autonomous Vehicles, Nischal Khadka Aug 2024

Analysis Of Traffic Operation And Safety At Cloverleaf And Diamond Interchanges With And Without Connected And Autonomous Vehicles, Nischal Khadka

LSU Master's Theses

Even though diamond and cloverleaf interchanges are commonly used in road networks, comparative studies on their operational safety and efficiency remain limited. Also, previous studies have explored the impact of Connected and Autonomous Vehicles (CAVs) at diamond interchanges, but the effects on cloverleaf interchanges are not yet thoroughly investigated. This study addresses these gaps by evaluating the traffic operation and safety performance of cloverleaf interchanges compared to diamond interchanges. It also assesses the influence of various Market Penetration Rates (MPRs) of CAVs on travel time, queue lengths, and conflict points at cloverleaf interchanges, considering different weaving lengths.

Data on peak-hour …


Chemistry And Processing Of Carbon/Carbon Composites From Furan-Based Polybenzoxazine Resins, Michael Chauby Aug 2024

Chemistry And Processing Of Carbon/Carbon Composites From Furan-Based Polybenzoxazine Resins, Michael Chauby

Theses and Dissertations

Carbon/carbon (C/C) composites are valuable for applications requiring structural integrity at high temperatures. However, their widespread use is limited by high manufacturing costs. Monofunctional furan-based benzoxazine resins were identified as promising candidates for enhancing fabrication efficiency due to their low viscosity, high char yield, and high carbon density. A benzoxazine monomer synthesized from furfurylamine, formaldehyde, and benzyl alcohol (Bz-FA-H) exhibits a crosslinking reaction between the furan group and the hydroxymethyl para substituent on the phenol, not found with other monomers. An investigation using blends of monomers containing Bz-FA-H at various concentrations showed that increasing crosslink density resulted in increased bulk …


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 Aug 2024

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 …


Metal Organic Frameworks Modified Textiles For The Detoxification Of Chemical Warfare Agent / Simulant, Selva Balasubramanian S Aug 2024

Metal Organic Frameworks Modified Textiles For The Detoxification Of Chemical Warfare Agent / Simulant, Selva Balasubramanian S

Theses and Dissertations

Chemical Warfare Agents (CWAs) have been listed as lethal weapons of mass destruction due to their extreme toxicity and devastating effects. Malfeasant usage of CWAs involved in the current world praxis poses threat to humankind. Owing to their acute lethal toxicity, the pursuit of favorable approaches for the detoxification/degradation are in continuous progress. In current trends, an imminent development of self-detoxification filters is highly desirable against the CWAs exposure. Exploiting protective materials that can be applicable in day – today life for an instantaneous detoxification will be of prodigious importance.

With this background, a series of Zirconium based UiO-66 and …


Approximate Computing And In-Memory Computing: The Best Of The Two Worlds!, Mohammed Essa Fawzy Essa Aug 2024

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 …


Beyond Measures Of Speed & Accuracy: Evaluating Visualization Perception, Reasoning & Decision-Making, Melanie Bancilhon Aug 2024

Beyond Measures Of Speed & Accuracy: Evaluating Visualization Perception, Reasoning & Decision-Making, Melanie Bancilhon

McKelvey School of Engineering Graduate Student Theses & Dissertations

Visualizations have long been used to support decision-making across various fields. By transforming complex data into graphical representations, such as charts, graphs, and maps, visualizations are generally reputed to make information more accessible and comprehensible for all. While prior work demonstrates that visualizations can improve speed and accuracy across comprehension and analytical tasks, there lacks research on how they can benefit decision-making. Decision-making is a complex task which involves risk comprehension and rational thinking but also various heuristics and external factors. While research has shown that individual traits and situational factors can impact performance with visualizations, they have not been …


A Coarse-Grained Molecular Dynamics Study Of Gas Hydrate Formation And Dissociation, Meisam Adibifard Aug 2024

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 …


The Effect Of Chromium Coatings On Hydrogen Uptake In Zirconium Alloy Nuclear Fuel Cladding, Jorie Lyn Walters Aug 2024

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 …


End-To-End Full-Width Induction Welding Of Unidirectional Tape-Based Thermoplastic Composites, Jaspreet Singh Pandher Aug 2024

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 …


Guiding 3d Chiral Self-Assembly At Nano/Micro Length Scales Via 3d Printing, Mohsen Esmaeili Aug 2024

Guiding 3d Chiral Self-Assembly At Nano/Micro Length Scales Via 3d Printing, Mohsen Esmaeili

Theses and Dissertations

This thesis delves into the intricate realm of 3D printing bio-inspired materials with tailored nano/microscale architectures. The first chapter investigates the flow-induced alignment of cellulose nanocrystals (CNC) during 3D printing, employing a microfluidic strategy integrated with polarized optical microscopy (POM). Birefringence measurements under varying conditions reveal the influence of initial CNC suspension structures on flow-induced patterns, particularly in the chiral nematic phase. Hydrodynamic simulations complement experimental findings, elucidating the impact on CNC particle alignment, providing insights for designing 3D printed architectures with internal chirality for advanced applications.

The second chapter explores the 3D printing of complex geometries inspired by Bouligand …


Classifying Floor Accelerations For Gait Estimation And Detection, Jean Michel Franco Lozada Aug 2024

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 Aug 2024

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, …


Developing A Hierarchical Digital Twin Framework For Dc Microgrid Implementation, Khari Sado Aug 2024

Developing A Hierarchical Digital Twin Framework For Dc Microgrid Implementation, Khari Sado

Theses and Dissertations

This research introduces a hierarchical digital twin framework for DC microgrids implementation, particularly those utilized in naval power systems. Unlike traditional digital twins, this hierarchical digital twin structure offers a layered perspective. Hierarchical digital twin design promotes computational efficiency by distributing computational burden across a layered configuration that integrates lower-level digital twin blocks with a system digital twin. The layered approach breaks down complex systems into smaller manageable units that can be examined individually and collectively. Central to this strategy is the adoption of a multi-domain and multi-functional technique through the integration of the digital image framework. This allows the …


Uav-Based Tracking And Following Of Railroad Lines, Keith Michael Lewandowski Aug 2024

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 Aug 2024

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 …


Erodibility Of Sand-Silt-Xanthan Gum Mixtures, Edwin Kotey Aug 2024

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 …


B-Spline Impulse Response Functions For Transient Ssi Analysis Of Pile Foundations, Kingsley C. Ozegbe Aug 2024

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 …


Mathematical Modeling And Reconstruction Of Porous Media To Understand Transport Phenomena For Electrochemical System Applications, Mitchell Sepe Aug 2024

Mathematical Modeling And Reconstruction Of Porous Media To Understand Transport Phenomena For Electrochemical System Applications, Mitchell Sepe

Theses and Dissertations

Alternative power generation has grown significantly in the space of energy production over the last ten years. Development of new technologies to produce energy is vital to the growing need for electricity. Batteries, solar panels, wind turbines, and countless other renewable energy options have been deemed necessary to create an overall greener future. Fuels cells when combined with electrolyzer show a promising system for stationary power generation. Both technologies are comprised of multiple parts in contact that must work together simultaneously to create an ideal environment for catalytic reactions to take place. A crucial component to a properly functioning cell …