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High-Resolution Groundwater Modeling For Understanding Sparta-Memphis Aquifer Condition, Rafin Hasan Jul 2024

High-Resolution Groundwater Modeling For Understanding Sparta-Memphis Aquifer Condition, Rafin Hasan

LSU Master's Theses

The Sparta-Memphis aquifer is one of the major sources of domestic and industrial water supplies in the Mississippi Embayment region. However, besides altering the natural direction of flow, several serious complications such as elevated chloride concentration, significant water level decline, large cones of depression, and land subsidence have arisen from excessive groundwater consumption. To better understand the Sparta-Memphis aquifer condition, a high-resolution groundwater flow model for the Sparta-Memphis aquifer was developed in this study to assess groundwater availability and analyze aquifer responses to future groundwater withdrawal scenarios. For the development of the groundwater flow model, firstly about 3,700 electrical log …


Copper-Based Electrocatalysts For Electrochemical Reduction Of Co2 To C2 Products, Monsuru Olatunji Dauda Jun 2024

Copper-Based Electrocatalysts For Electrochemical Reduction Of Co2 To C2 Products, Monsuru Olatunji Dauda

LSU Master's Theses

The electrochemical reduction of CO2 using copper-based electrocatalysts has emerged as a promising approach for sustainable chemical production, offering a pathway to mitigate the rising atmospheric CO2 levels while generating valuable fuels and chemicals. However, the selectivity and efficiency of copper-based catalysts towards specific C2 products remain a major challenge, hindering their commercial viability. This thesis focuses on the development, characterization, and mechanistic understanding of three promising electrocatalyst systems for multi-carbon product generation from CO2 reduction: copper-phosphide (Cu-P), copper-tin (Cu-Sn), and copper selenide (Cu2Se). A comprehensive investigation of the electrocatalysts was conducted using advanced …


A Feasibility Study Of Drilling Fluid Slippage For Wellbore Displacement, John Johnson Apr 2024

A Feasibility Study Of Drilling Fluid Slippage For Wellbore Displacement, John Johnson

LSU Master's Theses

In the ideal plug-flow mode viscoplastic drilling fluids display uniform frontal velocity due to wall slippage (at very low flowrate limited by the fluid’s yield strength). The flow rate could be increased by raising the yield strength that would make the fluid best candidate for frontal displacement. Based on this concept the study qualifies wall slippage effect for wellbore displacement. Using a conceptual model of fluid motion between two parallel plates defines maximum velocity as a function of shearing rate and yield stress. Conversion to coaxial geometry gives practical formulas for fluid testing with rotational viscometer. A new analysis of …


Cyber Attacks Against Industrial Control Systems, Adam Kardorff Apr 2024

Cyber Attacks Against Industrial Control Systems, Adam Kardorff

LSU Master's Theses

Industrial Control Systems (ICS) are the foundation of our critical infrastructure, and allow for the manufacturing of the products we need. These systems monitor and control power plants, water treatment plants, manufacturing plants, and much more. The security of these systems is crucial to our everyday lives and to the safety of those working with ICS. In this thesis we examined how an attacker can take control of these systems using a power plant simulator in the Applied Cybersecurity Lab at LSU. Running experiments on a live environment can be costly and dangerous, so using a simulated environment is the …


Investigation Of Gas Dynamics In Water And Oil-Based Muds Using Das, Dts, And Dss Measurements, Temitayo S. Adeyemi Mar 2024

Investigation Of Gas Dynamics In Water And Oil-Based Muds Using Das, Dts, And Dss Measurements, Temitayo S. Adeyemi

LSU Master's Theses

Reliable prediction of gas migration velocity, void fraction, and length of gas-affected region in water and oil-based muds is essential for effective planning, control, and optimization of drilling operations. However, there is a gap in our understanding of gas behavior and dynamics in water and oil-based muds. This is a consequence of the use of experimental systems that are not representative of field-scale conditions. This study seeks to bridge the gap via the well-scale deployment of distributed fiber-optic sensors for real-time monitoring of gas behavior and dynamics in water and oil-based mud. The aforementioned parameters were estimated in real-time using …


The Ecological Responses To Hydroperiod Of Wetland Plant Species Determined By Manipulated Soil Surface Elevation (Marsh Organs), Brandon Wolff Jan 2024

The Ecological Responses To Hydroperiod Of Wetland Plant Species Determined By Manipulated Soil Surface Elevation (Marsh Organs), Brandon Wolff

LSU Master's Theses

As sea level rise, subsidence, and abandonment of natural deltaic processes due to a highly engineered Mississippi River continue to threaten Louisiana’s coastal wetlands, the need for a system-wide understanding of natural wetland land-building and preservation processes has never been greater. A key component of any wetland is the ever-changing water environment that periodically floods and dries the marsh platforms. The flooding depth, duration, and frequency, known as the hydroperiod, along with salinity and soil fertility are key determining factors of vegetation and marsh types at a particular location. Different types of vegetation will have different growth characteristics such as …


Surrogate-Assisted Simulation-Optimization Framework For Groundwater Management In A Multi-Aquifer System, Melika Mani Nov 2023

Surrogate-Assisted Simulation-Optimization Framework For Groundwater Management In A Multi-Aquifer System, Melika Mani

LSU Master's Theses

Uncontrolled groundwater exploitation can lead to aquifer depletion, land subsidence, and saltwater intrusion. Effective groundwater management is challenging due to the intricate nature of subsurface hydrogeology and spatiotemporally variable pumping, especially in a multi-aquifer system. To ensure sustainable withdrawal, multi-objective optimization is an effective tool for balancing management goals and drawdown effects. However, running simulation-optimization using detailed groundwater models is computationally expensive, pushing decision-makers to decide based on limited scenarios. In this study, a hydrogeological framework was constructed for the Capital Area, Louisiana, allowing for individual assessment of each unit to better understand each aquifer's condition. Moreover, a surrogate-assisted simulation-optimization …


Carbonate Precipitation Behavior In Co2 Mea Electrolyzers With Cu Electrocatalyst, John C. Hendershot Nov 2023

Carbonate Precipitation Behavior In Co2 Mea Electrolyzers With Cu Electrocatalyst, John C. Hendershot

LSU Master's Theses

Annually, over 35 billion metric tons of carbon dioxide (CO2) are emitted into Earth’s atmosphere. The accumulated CO2 emissions in the atmosphere over the last century drive climate change. CO2 electroreduction (CO2ER) is an emerging technology that aims to recycle carbon emissions from the industrial sector by using CO2, H2O, and electricity as a feedstock to produce ethylene (C2H4) at current densities as high as 1 A cm-2 and Faradaic efficiencies (FE) of 60%. However, CO2 electrolyzers currently demonstrate poor durability at industrially relevant …


Integrating The Concept Of Complete Streets Into Pavement Preservation, Sirisha Gangireddy Nov 2023

Integrating The Concept Of Complete Streets Into Pavement Preservation, Sirisha Gangireddy

LSU Master's Theses

This study is motivated by the evident gap in integrating Complete Streets principles into pavement preservation. Complete Streets opportunities, which aim to accommodate all road users, are typically encouraged in all kinds of projects including new construction, reconstruction, preservation, and rehabilitation. While the concept of Complete Streets is understood in terms of new construction (e.g., building sidewalks), its application through pavement preservation programs is not well-developed. To bridge the gap between the Complete Streets and pavement preservation, this study conducted a comprehensive review on how state Department of Transportation (DOTs) are currently incorporating Complete Streets into pavement preservation and identified …


Multichannel Low-Cost Sensor For Iaq Monitoring: Implementation And Guidelines, Isaac Ntiamoah Oct 2023

Multichannel Low-Cost Sensor For Iaq Monitoring: Implementation And Guidelines, Isaac Ntiamoah

LSU Master's Theses

Indoor air quality (IAQ) is adversely affected by both indoor and outdoor environments, and rental homes occupied by low-income families suffer the most. Poor indoor air can be detrimental to the health of occupants, especially for susceptible populations like those with respiratory diseases such as asthma. Although IAQ monitoring is necessary, it is a challenging, costly, and time-intensive task. Moreover, the protocol for assessing IAQ in residential settings varies, and additional research is needed to establish a standard operating procedure that incorporates new monitoring technologies, such as low-cost air sensors. However, there is a dearth of comprehensive, evidence-based protocols for …


The Effects Of Disruption Type, Trip Purpose, Gender, And Age On Driver Diversion Willingness In The United States Of America, James D. Fuller Oct 2023

The Effects Of Disruption Type, Trip Purpose, Gender, And Age On Driver Diversion Willingness In The United States Of America, James D. Fuller

LSU Master's Theses

When drivers encounter traffic congestion, one of the most common ways to avoid excessive delays is to divert to an alternate route. Despite the commonplace nature of such routing decisions, relatively little is known about the specific influencers, motivators, and preferences that affect diversion choices under disrupted conditions. Understanding these driver motivations is important for improving the ability of transportation authorities to plan, design, operate, and maintain transportation networks. The research described in this thesis utilizes a driver survey to investigate the situational factors and personal characteristics that may play a significant role in determining a decision to divert or …


Bim And Digital Twins In Infrastructure Projects: An Overview From The Transportation Professional's Perspective, Natállia Mendes Aug 2023

Bim And Digital Twins In Infrastructure Projects: An Overview From The Transportation Professional's Perspective, Natállia Mendes

LSU Master's Theses

Transport infrastructure has undergone significant changes in recent years due to the digitalization of construction methods. Consequently, there is an increasing demand for more productive and cost-effective technologies to optimize various aspects such as time, cost, changes, waste, and errors in projects. Notably, technologies such as Building Information Modeling (BIM) and Digital Twin (DT) hold the potential to enhance the performance of infrastructure projects. While BIM has received substantial attention in recent years, Digital Twin is relatively new to the construction industry. This leads to a scarcity of studies on DT and its integration with other emerging technologies like BIM. …


Design And Implementation Of An Instrument Package For Measuring Process Conditions In An Expeller, Md Masud Rana Aug 2023

Design And Implementation Of An Instrument Package For Measuring Process Conditions In An Expeller, Md Masud Rana

LSU Master's Theses

The expeller process variable has gained increasing attention in research to validate process flow models. The expeller process is a mechanical method used to extract oil and water from seeds, nuts and polymers. Various factors, such as the speed of the press, size, and shape of the expeller, temperature, pressure, and moisture content, impact the efficiency and quality of the oil and water extraction process. By understanding these variables, researchers can develop accurate process flow models to predict the efficiency and quality of the oil and water extraction process. In this research, A custom instrumentation package have designed and implemented …


A Multi-Aerial Vehicle Platform For Testing Collaborative Mobility Formation Controllers, Matthew Snellgrove Aug 2023

A Multi-Aerial Vehicle Platform For Testing Collaborative Mobility Formation Controllers, Matthew Snellgrove

LSU Master's Theses

Multi-agent systems have potential applications in a multitude of fields due to their ability to perform complex tasks with a high degree of robustness. Decentralized systems are multi-agent systems where sensing, control, and communication responsibilities are distributed amongst the agents giving this scheme a particularly high potential for robustness, adaptability, and complexity; however, this comes with its own list of challenges. Formation control is a topic in multi-agent systems that aims to have the agents moving as a virtual rigid body through space. In the literature, there have been successful implementation of formation control algorithms on robot agents in both …


Investigating The Influence Of Portland Limestone Cement Combined With Sugarcane Bagasse Ash And Different Types Of Fly Ash On The Mechanical Properties Of Engineered Cementitious Composites, Samuel Guidroz Aug 2023

Investigating The Influence Of Portland Limestone Cement Combined With Sugarcane Bagasse Ash And Different Types Of Fly Ash On The Mechanical Properties Of Engineered Cementitious Composites, Samuel Guidroz

LSU Master's Theses

The ability to implement Engineered Cementitious Composites (ECC) within our transportation infrastructure systems has been limited because of increased costs associated with the material’s high cement quantity. To improve cost- effectiveness and to create a more sustainable footprint, the use of supplementary cementitious materials (SCMs) has been explored. This study evaluated the effects of utilizing cement interground with limestone, Portland limestone cement (PLC), as a replacement for ordinary Portland cement (OPC). Additionally, the performance of the composites was analyzed when mixed with sugarcane bagasse ash (SCBA) as well as different classes of fly ash (FA). In doing so, the experimental …


Autonomous Shipwreck Detection & Mapping, William Ard Aug 2023

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% …


Development And Calibration Of The Lmrpm Mid-Breton River Sediment Diversion Gate Operations, Emily E. Fertitta Jul 2023

Development And Calibration Of The Lmrpm Mid-Breton River Sediment Diversion Gate Operations, Emily E. Fertitta

LSU Master's Theses

With the rate of coastal land loss in Louisiana, the state is looking for innovative ways to help restore and maintain its coastal wetlands. Sediment diversions are going to be constructed along the Lower Mississippi River to mitigate the issues by diverting river water, sediment and nutrients into adjacent wetlands. Since there are currently no real-world applications of sediment diversions, the Lower Mississippi River Physical Model is a beneficial modeling tool to study the impact sediment diversions and relative sea level rise have on the hydraulics and sediment transport processes in the river. The two river sediment diversions on the …


Bound Preserving Numerical Methods For Infiltration, Arnob Barua Jul 2023

Bound Preserving Numerical Methods For Infiltration, Arnob Barua

LSU Master's Theses

Simulating the infiltration process in variably saturated media by solving Richards' Equation (RE) remains a computationally challenging task. The degenerate parabolic nature of RE, along with the strongly nonlinear coefficients, makes it very difficult to obtain accurate solutions with conventional numerical methods unless highly refined meshes are used. That is, in the conventional Finite Element Method (FEM), the grid size has to be fine enough to ensure convergence and limit non-physical oscillations, which is computationally expensive. This research aims to develop a second-order accurate FEM discretization with no non-physical oscillations for RE on unstructured meshes which will converge faster than …


Wave Attenuation Through Mangrove Forest Using Lidar Representation, Elizabeth Bogan Jul 2023

Wave Attenuation Through Mangrove Forest Using Lidar Representation, Elizabeth Bogan

LSU Master's Theses

Mangrove forests can be found along the world’s intertidal tropical and sub-tropical coastlines. These forested wetlands provide many ecosystem services, including supporting coastal food chains, trapping sediment, and shoreline stabilization. Mangroves are also known for flood damage mitigation by dissipating waves and surge during flooding events. Thus, coastal communities declare a vested interest in the performance of the forest to mitigate flood damage. Physical models using artificial mangrove structures have shown that red mangrove-dominated fringe forests can protect built infrastructure by reducing wave height due to increased drag. One way to estimate the contribution of red mangrove (Rhizophora mangle) prop …


Automated Reinforcement In Construction 3d Printing: An Investigation Of Mechanical And Macrostructural Performance Of Reinforced 3d-Printed Structures, Hassan Ahmed Jun 2023

Automated Reinforcement In Construction 3d Printing: An Investigation Of Mechanical And Macrostructural Performance Of Reinforced 3d-Printed Structures, Hassan Ahmed

LSU Master's Theses

Conventional construction with steel reinforcement is widely accepted and utilized worldwide for its proven strength, durability, design flexibility, cost-effectiveness, and due to available standards and design codes. Integration of reinforcement in construction 3D printing, however, presents multi-faceted challenges that may influence the structural properties of printed components and have hindered the widespread adoption of reinforced 3D-printed structures. This study explored two complementary reinforcement techniques, namely, steel fibers and threaded reinforcement, to reinforce 3D-printed structures. This study explored both the fresh and hardened properties of 3D-printed mixtures that contain very high steel fiber dosages of up to 2.5% by volume. Additionally, …


Remote Sensing And Artificial Intelligence-Based Modeling And Prediction Of Harmful Algal Blooms In Lake Pontchartrain, Ian Smith May 2023

Remote Sensing And Artificial Intelligence-Based Modeling And Prediction Of Harmful Algal Blooms In Lake Pontchartrain, Ian Smith

LSU Master's Theses

Harmful Algal Blooms (HABs) and particularly toxic cyanobacterial harmful algal blooms (CyanoHABs) have become a growing threat to the environment, economy, communities, and human and animal health. This is particularly true for Lake Pontchartrain. Forecasting the occurrence of cyanobacterial HABs in Lake Pontchartrain is a process that currently does not exist, as nowcasting by the NCCOS Algal Bloom Monitoring System or the similar system implemented by the U.S. EPA is currently the only method to monitor HAB production in the Lake. This thesis made this process possible by identifying antecedent environmental conditions controlling CyanoHABs, describing the conditions using NASA satellite …


Behavioral Comparison Of Fluorescent Tracer Sediment To Lightweight Polystyrene Sediment Of The Lower Mississippi River Physical Model (Lmrpm), Julia C. Mudd May 2023

Behavioral Comparison Of Fluorescent Tracer Sediment To Lightweight Polystyrene Sediment Of The Lower Mississippi River Physical Model (Lmrpm), Julia C. Mudd

LSU Master's Theses

A lightweight, unexpanded polystyrene sediment with a specific gravity of 1.05 and a D10, D50 and D90 of 0.250 mm, 0.425mm, and 0.800 mm, respectively, is utilized in the Lower Mississippi River Physical Model (LMRPM) at Louisiana State University to mimic the sand transport of the Lower Mississippi River. While the black model sediment is easily visible against the stark white of the LMRPM, the relative homogeneity of the sediment particles and the opaqueness of the model channel make it difficult to closely study sediment dynamics during an experiment. For this reason, a tracer sediment that is marked with fluorescence …


Exploring Machine Learning In Deep Foundation And Soil Classification Application, Mohammad Moontakim Shoaib May 2023

Exploring Machine Learning In Deep Foundation And Soil Classification Application, Mohammad Moontakim Shoaib

LSU Master's Theses

The applicability of several Machine Learning (ML) models was explored in this research to predict the ultimate capacity and load-settlement behavior of axially loaded single-driven piles from Cone Penetration Test (CPT) data. Additionally, a common CPT-based soil behavior type (SBT) classification system was reproduced using those ML models. Eighty static pile load tests and corresponding CPT data close to those pile locations were collected from 34 sites in Louisiana for the deep foundation application. On the other hand, 70 CPT soundings were taken in 14 different parishes across Louisiana for the soil classification application. Specifically, tree-based ML models such as …


An Investigation On The Resilience Of Long Short-Term Memory Deep Neural Networks, Christopher Vasquez May 2023

An Investigation On The Resilience Of Long Short-Term Memory Deep Neural Networks, Christopher Vasquez

LSU Master's Theses

In a world of continuously advancing technology, the reliance on these technologies continues to increase. Recently, transformer networks [22] have been implemented through various projects such as ChatGPT. These networks are extremely computationally demanding and require cutting-edge hardware to explore. However, with the growing increase and popularity of these neural networks, a question of reliability and resilience comes about, especially as the dependency and research on these networks grow. Given the computational demand of transformer networks, we investigate the resilience of the weights and biases of the predecessor of these networks, i.e. the Long Short-Term (LSTM) neural network, through four …


Optimization Of The Self-Healing Efficiency Of Bacterial Concrete Using Impregnation Of Three Different Precursors Into Lightweight Aggregate, Omar Omar May 2023

Optimization Of The Self-Healing Efficiency Of Bacterial Concrete Using Impregnation Of Three Different Precursors Into Lightweight Aggregate, Omar Omar

LSU Master's Theses

Concrete is the most broadly used construction material; thus, developing sustainable concrete is essential to decrease greenhouse gas (GHG) emissions from concrete production. Implementation of self-healing concrete technologies is a promising approach to enhance the durability and sustainability of the transportation infrastructure. Among these technologies, bacterial concrete has the potential to seal microcracks through microbial induced calcite precipitation (MICP). Bacterial protection is essential to ensure the viability of this technology due to concrete’s harsh environment. Additionally, the success of this technology depends on the presence of an adequate mineral precursor compound and nutrient for the bacteria. As such, the main …


Numerical Flume For Wave Dissipation By Mangrove Prop Roots, Rebecca L. Schurr Apr 2023

Numerical Flume For Wave Dissipation By Mangrove Prop Roots, Rebecca L. Schurr

LSU Master's Theses

Mangroves provide shorelines with many beneficial engineering services, including shoreline stabilization, wave attenuation, and damage mitigation during tsunami or tropical cyclone events. This research focuses on wave attenuation rates and drag coefficients, and how they are affected by mangrove prop roots. Previous lab research using a physical wave flume has quantified wave height decay and drag coefficients for synthetic mangrove forests and confirmed that attenuation does indeed increase as mangrove forest density increases. This research will use a 3D numerical flume model developed in Proteus, a Python package, to simulate prior physical model experiments. This work will attempt to validate …


Deposition, Material Characterization, And Mechanical Testing Of Cr Containing Diamond-Like Carbon Films, Nicholas Anderson Apr 2023

Deposition, Material Characterization, And Mechanical Testing Of Cr Containing Diamond-Like Carbon Films, Nicholas Anderson

LSU Master's Theses

A series of amorphous hydrogenated chromium containing diamond-like carbon films were deposited on 316 stainless steel substrates with a chromium interlayer through inductively coupled plasma assisted direct current magnetron sputtering. Details on the deposition process of these films are discussed. The film is characterized using scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, energy dispersive spectroscopy, and transmission electron microscopy. The coating hardness and indentation modulus is measured by instrumented nanoindentation. The coefficient of friction and the upper bound of the coating wear coefficient is measured using the pin-on-disk method. The fracture toughness of the diamond-like carbon film and a …


Improved Selectivity And Stability In Methane Dry Reforming By Atomic Layer Deposition Onto Ni-Ceo2-Zro2/Al2o3 Catalysts, Jonathan Lucas Mar 2023

Improved Selectivity And Stability In Methane Dry Reforming By Atomic Layer Deposition Onto Ni-Ceo2-Zro2/Al2o3 Catalysts, Jonathan Lucas

LSU Master's Theses

The use of Ni in the dry reforming of methane (DRM) has been widely studied as a replacement for noble metal catalysts (Pt, Pd, Rh) due to Ni’s low cost compared to noble metals, its abundance, and the fact that its DRM activity is near that of noble metal catalysts. However, Ni has been shown to deactivate quickly under DRM conditions. Rare earth oxides such as CeO2, or as CeO2-ZrO2 (CZO) are supports that improve both the activity and stability of Ni DRM systems due to their redox activity. However, this same activity is thought …


Cable Decoupling And Cable-Based Stiffening Of Continuum Robots, Parsa Molaei Mar 2023

Cable Decoupling And Cable-Based Stiffening Of Continuum Robots, Parsa Molaei

LSU Master's Theses

Cable-driven continuum robots, which are robots with a continuously flexible backbone and no identifiable joints that are actuated by cables, have shown great potential for many applications in unstructured, uncertain environments. However, the standard design for a cable-driven continuum robot segment, which bends a continuous backbone along a circular arc, has many compliant modes of deformation which are uncontrolled, and which may result in buckling or other undesirable behaviors if not ameliorated. In this study, a detailed approach for using additional cables to selectively stiffen planar cable-driven robots without substantial coupling to the actuating cables is investigated. A mechanics-based model …


Motivators And Preferences Of Route Diversion During Roadway Incidents, Grace Cole Mar 2023

Motivators And Preferences Of Route Diversion During Roadway Incidents, Grace Cole

LSU Master's Theses

When confronted with congestion and delay, drivers often divert their route. Depending on factors like purpose, urgency, destination, route alternatives, type of disruption, and mode options, common diversionary options can range from changing departure time, route, and mode to canceling a trip altogether. One of the foundational building blocks of travel forecasting is traffic assignment, which is used to distribute trips over a network using complex algorithms to aggregately represent the desire of drivers to minimize travel time.

While these assignment models are backed by decades of research and observational experience, they are also limited by the fact that they …