Engineering Commons^™

Reliability Analysis Of Concrete Gravity Dams Under Earthquake Loads, Anu Abraham

LSU Master's Theses

Dams are infrastructure assets of extreme importance; the failure of which can have catastrophic consequences on adjacent communities. Therefore, it is prudent for authorities to evaluate the safety of existing dams in seismically active regions. This thesis focuses on carrying out a reliability analysis of concrete gravity dams under earthquake loads using an enhanced finite element model. For many years, reliability studies on concrete gravity dams were performed using a finite element model that considered a massless foundation and assumed that water is incompressible. Moreover, the design ground motion was applied without any modification either at the bottom fixed boundary …

Study Of The Effect Of Heating - Cooling Cycles On The Clay - Concrete Pile Interface Characteristics, Abedalqader Ahmad Idries

LSU Master's Theses

This study aimed at investigating the effect of heating-cooling cycles on the interface strength parameters of clay soil-concrete for potential applications to improve the side capacity of piles driven in clayey soil by the heating process, and also to assess the behavior of geothermal piles regarding interface shear strength parameters. A modified large-size direct shear test device with the dimensions 12” x 12” x 8”, was used in this study. A concrete block (12” x 12” x 4”) of similar texture and smoothness to the concrete piles was used to simulate the pile interface. The tested clays are low plasticity …

Identification Of Top-Down, Bottom-Up, And Cement-Treated Reflective Cracks Using Convolutional Neural Network And Artificial Neural Network, Nirmal Dhakal

LSU Doctoral Dissertations

The objective of this study was to formulate a Convolutional Neural Networks (CNN) model and to develop a decision-making tool using Artificial Neural Networks (ANN) to identify top-down, bottom-up, and cement treated (CT) reflective cracking in in-service flexible pavements. The CNN’s architecture consisted of five convolutional layers with three max-pooling layers and three fully connected layers. Input variables for the ANN model were pavement age, asphalt concrete (AC) thickness, annual average daily traffic (AADT), type of base, crack orientation, and crack location. The ANN network architecture consisted of an input layer of six neurons, a hidden layer of ten neurons, …

Understanding Air Pollutants And Meteorology Interactions Using Chemical Transport Models, Pengfei Wang

LSU Doctoral Dissertations

Air pollution is a worldwide threat to human health and ecosystems, especially in developing countries. After being emitted to the atmosphere, air pollutant concentrations are determined by chemical and physical processes including transport, transformation, and deposition, which are largely affected by meteorological variations. In turn, pollutants such as fine particulate matter (PM_2.5) affect meteorology by impacting solar radiation and cloud condensation processes. Thus, it is important and necessary to understand the interactions between air pollutants and meteorology for better designing effective air pollution control strategies and forecasting weather. In this study, two chemical transport models (CTMs) are applied …

Evolution Of Computational Thinking Contextualized In A Teacher-Student Collaborative Learning Environment., John Arthur Underwood

LSU Doctoral Dissertations

The discussion of Computational Thinking as a pedagogical concept is now essential as it has found itself integrated into the core science disciplines with its inclusion in all of the Next Generation Science Standards (NGSS, 2018). The need for a practical and functional definition for teacher practitioners is a driving point for many recent research endeavors. Across the United States school systems are currently seeking new methods for expanding their students’ ability to analytically think and to employee real-world problem-solving strategies (Hopson, Simms, and Knezek, 2001). The need for STEM trained individuals crosses both the vocational certified and college degreed …

Engineering Dopant Position In Structure-Controlled Ceo2-Zro2 Catalysts, Behnam Safavinia

LSU Master's Theses

CeO₂-ZrO₂ (CZO) nanoparticles (NPs) have application in many catalytic reactions, such as methane reformation, due to their oxygen cycling ability. Ni doping has been shown to improve the catalytic activity and acts as an active site for the decomposition of methane. In this work, Ni:CZO NPs were synthesized via a two-step co-precipitation/molten salt synthesis to compare Ni distribution, oxygen vacancy concentration, and catalytic activity relative to a reference state-of-the-art catalyst. To better understand the effects of Ni position and dispersion, and oxygen vacancy formation in these materials, the Ni concentration, reaction time, and deposition methods were varied. …

Temporal Decomposition For Multi-Interval Optimization In Power Systems, Farnaz Safdarian

LSU Doctoral Dissertations

Large optimization problems are frequently solved for power systems operation and analysis of electricity markets. Many of these problems are multi-interval optimization with intertemporal constraints. The size of optimization problems depends on the size of the system and the length of the considered scheduling horizon. Growing the length of the scheduling horizon increases the computational burden significantly and might make solving the problem in a required time span impossible. Many simplifications and approximation techniques are applied to reduce the computational complexity of multi-interval scheduling problems and make them solvable in a reasonable time span. Geographical decomposition is presented in the …

Source Apportionment Of Ozone And Its Health Effects In North China Plain And Southeast U.S., Kaiyu Chen

LSU Doctoral Dissertations

Ground-level ozone (O₃), as one of six common air pollutants set by National Ambient Air Quality Standards from the U.S. Environmental Protection Agency (EPA), is of great interest due to its health and economical effects. However, O₃ contributions from different emission sources are not well understood due to its complicated nonlinear reactions. In this study, O₃ source apportionment methods and the applications are firstly reviewed to provide a comprehensive understanding for O₃ formations. Application of High-order Decoupled Direct Method (HDDM), brute force method (BFM), O₃ source apportionment technology (OSAT) and source-oriented method in O …

Evaluation Of Undrained Shear Strength Of Soil, Ultimate Pile Capacity And Pile Set-Up Parameter From Cone Penetration Test (Cpt) Using Artificial Neural Network (Ann), Md Ariful Hassan Mojumder

LSU Master's Theses

Over the years, numerous design methods were developed to evaluate the undrained shear strength, S_u, ultimate pile capacity and pile set-up parameter, A. In recent decades, the emphasis was given to the in-situ cone and piezocone penetration tests (CPT, PCPT) to estimate these parameters since CPT/PCPT has been proven to be fast, reliable and cost-effective soil investigation method. However, because of the paucity of a vivid comprehension of the physical problem, some of the developed methods incorporate correlation assumptions which might compromise the consistent accuracy. In this study, the Artificial Neural Network (ANN) was exerted using CPT data …

Engineering Ionomer Materials For Addressing Ohmic Resistances In Electrochemical Desalination And Waste Heat Recovery, Varada Menon Palakkal

LSU Doctoral Dissertations

Water scarcity and energy availability present important challenges that need to be addressed in the coming centuries. In the front of water technologies, desalting brackish water is of extreme importance for thermal electric power plants, chemical manufacturing plants, and other industrial operations that treat and reuse their water utilities. Membrane capacitive deionization (MCDI) is an energy efficient desalination technique that has drawn attention from commercial entities. Most material research studies on MCDI focus on enhancing electrode performance while little emphasis is given to rationale design of ion-exchange membranes (IEMs). In this work, the ionic conductivity, permselectivity, and thickness for three …

Alternative Methods, Hunter Stabler

LSU Master's Theses

ABSTRACT

In the realm of precognitive artmaking, the artist’s role is that of an antenna. One must be receptive to the subtle, invisible flow of creative novelty in order to participate in the involuntary channeling of new ideas, new processes, and alternative methods of creative production. Carving out new territory within the realm of static art is a primary objective for my artistic process. By utilizing digital fabrication tools, paired with my affinity for intricate craft and optical metagrobolization, I have created a body of work that invents alternative processes and unique aesthetic languages.

Digital imaging, digital modeling and digital …

Design Of A Laminated Carbon Fiber I-Beam, Kyle Huber

Honors Theses

No abstract provided.

Theoretical Investigation Of Fundamental Cathode Processes In Metal-02 Batteries, Saurin Hiren Rawal

LSU Doctoral Dissertations

In this thesis we theoretically explore the different fundamental phenomena associated with metal-air batteries (where the metal can be Li, Na or K) using first principles density functional theory. We start by investigating the adsorption of the starting reactants/primary intermediates i.e. metal superoxides and superoxide anion on Au(111) and Au(211). We elucidate the influence of electric fields and the importance of including explicit solvents on the adsorption energy of these intermediates. We show that these effects are considerable and should be included for future reaction modeling of these batteries. Following this we investigate the reaction of M⁺ and O …

The Siltcatcher: A Sediment-Capture System For Wetland Creation And Coastal Protection In Western Lake Pontchartrain, Andrew M. Wright

LSU Master's Theses

The West Lake Pontchartrain region faces a number of long-term environmental challenges due to anthropogenic climate disturbance and landscape modification, including sea level rise, increased storm surge risk, shoreline erosion, and wetland degradation. In response, this thesis applies recent research in the fields of landscape architecture and civil engineering to propose a dynamic, natural-systems solution for wetland creation and shoreline protection. The project envisions a series of breakwater-like structures in western Lake Pontchartrain positioned to slow water released from the nearby Bonnet Carré Spillway, causing suspended sediment to settle and create self-building and self-sustaining wetlands capable of keeping pace with …

Why Do You Take That Route?, Alimire Nabijiang

LSU Master's Theses

We conducted this study to investigate causal factors which affects the route-choice behavior of drivers. Due to the insufficiency of measured variables and the lack of high-fidelity properties obtained by conventional data, we carried out Stated Choice Experiment (SCE) using Immersive Virtual Environments (IVE) tool to collect data. IVE tool can provide realistic virtual experiences to participants, and give advantage of flexible environment for exploring causal factors of drivers’ decision on route choice. Based on reviewing literatures, we believe that there is limited studies that has tried to comprehend the route choice behavior of drivers using causal inference. The study …

Evaluating The Effectiveness Of Continuing Education At Emergency Medical Services, Tasmia Mustaquim

LSU Master's Theses

Emergency Medical Services (EMS) require staff to recertify periodically, which involves a significant amount of continuing education. Great effort is given to designing and delivering a continuing education program, but it is also important to know if the training had all of the intended impacts. Nationally, there is no evidence-based system in place for training evaluation at EMS. This research proposes a framework being used at East Baton Rouge Parish Emergency Medical Services (EBRP-EMS) to evaluate a course, generate reports to indicate the performance of staff, and identify areas of improvement.

The Kirkpatrick Model, which is a 4-level evaluation, is …

Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen

LSU Doctoral Dissertations

The Mississippi River Delta is threatened by a growing pressure to support large human populations in the United States both with food production, navigation systems, and urban development in the Mississippi River Basin. Nitrate-nitrogen load in the Mississippi River, up to 100 Tg N yr^-1 from agricultural and urban runoff, leads to phytoplankton blooms and hypoxia across the Louisiana continental shelf, creating dead zones of low dissolved oxygen threatening a significant commercial fishery. Along the coast and river corridors, floodplain ecosystems have the capacity to retain and remove nitrate. This dissertation explores the role of productive, actively growing coastal …

The Long-Term Outlook Of The Mississippi-Atchafalaya Bifurcation: A Convergence Of Engineering, Economics, And Deltaic Evolution, Thomas Mitchell Andrus

LSU Doctoral Dissertations

The most recent and currently active delta lobe of the Mississippi River (MR) is the Atchafalaya-Wax Lake lobe, which was initiated approximately 400 years ago as a result of MR stream capture by the Atchafalaya River (AR). This capture process accelerated in the early to mid-1900s but further progress was prevented by construction and operation of the Old River Control Structure (ORCS) Complex. Many recent studies indicate that MR system below the ORCS is on a retreating geologic trajectory due to contributing factors such as sea level rise, subsidence, faulting, and declining hydraulic stream power. Diversions along the Lower MR …

Study Of Fundamental Tradeoff Between Deliverable And Private Information In Statistical Inference, Farhang Bayat

LSU Doctoral Dissertations

My primary objective in this dissertation is to establish a framework under which I launch a systematic study of the fundamental tradeoff between deliverable and private information in statistical inference. My research was partly motivated by arising and prevailing privacy concerns of users in many machine learning problems.

In this dissertation, I begin by introducing examples where I am concerned of privacy leakage versus decision utility in statistical inference problems. I then go into further details about what I have achieved in formulating and solving such problems using information theory related metrics in a variety of settings. Both related works …

Internals In Gas-Liquid Systems, Sai Sankar Ganesan

LSU Doctoral Dissertations

The objective of this study is to model gas-liquid contact and separation problems (using Euler-Euler based Computational Fluid Dynamic (CFD) models) at different scales. We have explored process intensive solutions, design optimizations by introducing internals in these gas-liquid operations.

A 500L pilot plant scale and a 7000L industrial scale novel down-flow bubble column problems were modeled. Methodologies used to overcome challenges on large-bubble micro-bubble dynamics are discussed and the resulting fluid dynamic solutions were studied. These solutions were further modified and tailored toward intensification, by exploring horizontal plate internals. We then modeled mass transfer and reaction kinetics on this system …

A Data-Driven Model For Multiphase Flow In Pipes, Francisco Bruno Xavier Teles

LSU Master's Theses

Steady-state models commonly used to determine pressure gradient in wells are either empirical correlations or are dependent on empirical parameters correlated to specific flow conditions such as pressures, temperatures, fluid types, and pipe inclinations. The empirical nature of these models leads to limitations in predicting cases in a wide range of conditions. Established models may be delivering inaccurate results when applied at conditions beyond those which they were derived from. For instance, models available in the literature have shown to have limitations when used in large diameter pipes and high-velocity scenarios.

This work aims to evaluate different flow models with …

Estimation Of The Axial And Lateral Capacity Of Driven Piles From The Results Of Cone Penetration Test And Finite Element Analysis, Mohsen Amirmojahedi

LSU Doctoral Dissertations

Piles play an important role in transportation and bridges. They are used to resist axial and lateral loads transferred to them from structures, earth pressures, incline loads, vehicles, etc. In this study, the capacity of piles for axial and lateral loads is investigated.

The ultimate axial capacity of piles can be estimated using different approaches including static pile load tests, dynamic load tests, statnamic load tests, and static analysis based on laboratory tests (effective and total stress approaches) or in-situ tests (SPT, CPT, etc.). For each approach, different researchers have proposed different solutions for different soils and different piles. Mostly, …

Implementing A Transporter Performance Management System In A Hospital Imaging Department, Sarah Dunn

Honors Theses

No abstract provided.

Tunable Luminescence Of Rare Earth Doped Nanophosphors Via Adaptive Optical Properties Of Transition Metals, Pragathi Darapaneni

LSU Doctoral Dissertations

Over the past decades, the development of light-emitting diodes (LEDs) to produce a wide range of wavelengths has revolutionized the solid-state lighting industry due to their higher energy efficiency and operational lifetimes. These LEDs employ rare earth (RE) doped phosphors due to their stable emission wavelengths which can be amplified when sensitized by other RE dopants (Yb, Ce) or shell layer passivation. However, there has been a push to replace the RE elements in LEDs due to increased socioeconomic issues. One proposed alternative, transition metal (TM) dopants, is typically avoided due to their susceptibility to the local crystal environment resulting …

Transition Metal-Doped Rare-Earth Oxysulfide Catalysts For High Temperature Dry Reforming Of Methane, Changyi Jiang

LSU Doctoral Dissertations

Carbon dioxide reforming of methane is a catalytic reaction utilizing two kinds of greenhouse gases and converting them into a useful industrial gas stream, “syngas”. However, sulfur poisoning and coke formation are two major challenges for this reaction. In this study, we have synthesized and examined several Ce-La and Ce-Zr oxides, with different transition metal additives. A rapid screening technique was developed to measure reforming and coking rates at low partial pressures. It is a good indicator of catalyst behavior at higher conversions and partial pressures. Following the rapid screening, select catalysts were examined at longer times on stream. Those …

Investigation Of Tracer-Surfactant-Foam Processes In Shallow Subsurface Environmental Remediation: History-Matching And Performance Prediction, Hazem Fleifel

LSU Master's Theses

In-situ subsurface remediation has been widely used as an efficient means of cleaning up non-aqueous phase liquid (NAPL) from contaminated soils and aquifer. The use of tracer, surfactant, and foam are often considered to keep track of the propagation of injected fluids in the medium, dissolve and mobilize contaminants trapped by capillary forces, and overcome the level of heterogeneity and improve displacement and sweep efficiencies.

This study shows an actual remediation process to reduce NAPL within a military base in South Korea, by injecting tracer and surfactant solutions together for a duration of 10 days. The site consists of 5 …

Barriers And Facilitators Influencing Compliance With Enhanced Recovery After Surgery Protocol: A Qualitative Study, Paige Boudreaux

LSU Master's Theses

Standardization in many industries has proven to lead to improved productivity and efficiency, however, standard practice in healthcare has proven difficult due to patient and physician variation. Evidence-based practices provide an opportunity to create more standardization. Enhanced Recovery After Surgery (ERAS) programs are attempting to standardize the surgical pathways of patients by implementing standard evidence-based steps, beginning in the surgeons office and continuing through a patients discharge (Ljungqvist, Scott, & Fearon, 2017). Implementing ERAS to standardize the surgical care of patients has shown to improve patient outcomes, reduce length of stay and reduce readmissions, however, there is a lack of …

Model Development To Assess Groundwater Flooding And Levee Underseepage In New Orleans, Louisiana, Shuo Yang

LSU Master's Theses

Flooding is a major threat to New Orleans due to its geographic location and geologic condition. However, potential groundwater flooding is seldom studied and poorly understood even though groundwater level is expected high in the city. High groundwater level might result in groundwater flooding in low-lying areas. High uplift pore water pressures may cause strong underseepage and risk levee safety. The objective of this study is to assess the impacts of hydrogeology on groundwater flooding and evaluate potential underseepage-induced hazards along levees in New Orleans. In this study, a groundwater flow model development which involves stratigraphy modeling, groundwater flow model …

Understanding And Optimizing Flash-Based Key-Value Systems In Data Centers, Yichen Jia

LSU Doctoral Dissertations

Flash-based key-value systems are widely deployed in today’s data centers for providing high-speed data processing services. These systems deploy flash-friendly data structures, such as slab and Log Structured Merge(LSM) tree, on flash-based Solid State Drives(SSDs) and provide efficient solutions in caching and storage scenarios. With the rapid evolution of data centers, there appear plenty of challenges and opportunities for future optimizations.

In this dissertation, we focus on understanding and optimizing flash-based key-value systems from the perspective of workloads, software, and hardware as data centers evolve. We first propose an on-line compression scheme, called SlimCache, considering the unique characteristics of key-value …

Contextual Adjustment Of The Ite Trip Generation Rates Using Wi-Fi And Bluetooth Technologies, Saba Doulabi

LSU Master's Theses

The ITE Trip Generation Handbook has been in common use for about half a century to estimate vehicle trips generated by more than 172 land use categories as a function of establishment size (floor area) only. However, observed trip rates display a huge error range across different sites. Although contextual adjustment factors can ameliorate the error in the ITE trip generation estimates considerably, local site-specific trip generation rates should be collected for this purpose. Due to the huge time and monetary costs of data collection, adjusting the ITE trip generation rate is ignored by many jurisdictions. The primary contribution of …