Digital Commons Network^™

Distributed Load Testing By Modeling And Simulating User Behavior, Chester Ira Parrott

LSU Doctoral Dissertations

Modern human-machine systems such as microservices rely upon agile engineering practices which require changes to be tested and released more frequently than classically engineered systems. A critical step in the testing of such systems is the generation of realistic workloads or load testing. Generated workload emulates the expected behaviors of users and machines within a system under test in order to find potentially unknown failure states. Typical testing tools rely on static testing artifacts to generate realistic workload conditions. Such artifacts can be cumbersome and costly to maintain; however, even model-based alternatives can prevent adaptation to changes in a system …

Experiential Statistics: A Case Study In Favor Of Using Project-Based Learning To Advance Preliminary Statistics Content Knowledge In The Algebra I And Geometry Classroom, Trey Michael Earle

LSU Doctoral Dissertations

Preparing secondary students for college entrance requirements and the expectations of the job market, a market which is actively seeking the employees who are most qualified to take on jobs that require data analysis skills, is becoming increasingly important. Federal, state, and local education administrators and personnel must rewrite many of the general education curricula to incorporate data organization, collection, manipulation, application, and analysis in order to better prepare students for the expectations of college entrance and an ever-changing employment market. From a purely pedagogical standpoint, while traditional educational structure has been commonplace for decades in the United States, projects …

Identification Of Blda As A Major Regulator Of Virulence In The Sweetpotato Soil Rot Pathogen Streptomyces Ipomoeae And Characterization Of Distinct Clostridium Sweetpotato Soft Rot Isolates, Kuei-Ting Yang

LSU Doctoral Dissertations

Streptomyces ipomoeae is the causative agent of Streptomyces soil rot on sweetpotato, a disease characterized by extensive necrosis of both adventitious and storage roots. While Streptomyces potato scab pathogens produce a phytotoxin (thaxtomin A), which is induced in the presence of cellobiose and suberin, S. ipomoeae produces a less-modified, phytotoxin (thaxtomin C), whose inducer has not been identified. To investigate transcriptional regulation of thaxtomin C production, we inserted a promoter involved in thaxtomin C synthesis upstream of the gusA reporter in an S. ipomoeae strain. Reporter gene expression was significantly upregulated in the presence of size-fractionated sweetpotato extract (SPE). The …

Interface Engineering Of Materials For Energy And Biological Applications, Ardalan Chaichi

LSU Doctoral Dissertations

Interface interactions are generally classified into solid-liquid, solid-gas, solid-vacuum, liquid-gas, light-matter and electron-matter categories. Surface morphological studies as well as surface chemical reactions can be studied in various types of complex systems thanks to technological advances in materials characterization methods. By employing interface engineering in different applications, it is possible to control electrical, chemical, mechanical, optical and biological properties of materials. Accordingly, we have applied interface engineering in three different areas of energy materials, biomaterials and surface imaging. As a result, firstly, we have introduced a high intensity light flash-based method on engineered substrates for delamination of reduced graphene oxide …

Student Perceptions Of Rules For Classroom Interaction, Hanson Paul Leblanc Iii

LSU Master's Theses

ABSTRACT

Burgoon’s expectancy violation model posits that nonverbal rule violations will be evaluated according to the perceptions toward the violator and the behavior itself. However, the violator may have perceptions regarding the appropriateness of the rule. This study measured the perceptions of high school students regarding the rules for classroom interaction. It is believed that the rules for classroom interaction are rules which have been learned through the process of socialization and enculturation into the classroom setting throughout students’ careers. These rules should be well known by all students by the time they reach tenth grade, the grade being investigated. …

Synthesis Of Structurally Diverse Molecular Scaffolds Enabled By Protected Oxyallyl Cations, Joshua Andrew Malone

LSU Doctoral Dissertations

This dissertation focuses on the synthesis of diverse molecular scaffolds through the use of protected oxyallyl cation intermediates. Chapter One provides background on the generation and applications of oxyallyl and silyloxyallyl cations, while focusing on the direct nucleophilic capture of theses intermediates to generate functionalized ketones and silylenolates. Chapter Two depicts our approach to generate six-membered silyloxyallyl cations through the use of mild Brønsted acid activation. Regioselective nucleophilic capture of these intermediates successfully produced diverse a,a’-substituted silylenol ethers enabled by polar solvent and residual water.

Chapter three details strategies to generate 1,4-dicarbonyl compounds, focusing on the capture of cationic intermediates …

Reinforcement Learning Approach For Inspect/Correct Tasks, Hoda Nasereddin

LSU Doctoral Dissertations

In this research, we focus on the application of reinforcement learning (RL) in automated agent tasks involving considerable target variability (i.e., characterized by stochastic distributions); in particular, learning of inspect/correct tasks. Examples include automated identification & correction of rivet failures in airplane maintenance procedures, and automated cleaning of surgical instruments in a hospital sterilization processing department. The location of defects and the corrective action to be taken for each varies from task episode. What needs to be learned are optimal stochastic strategies rather than optimization of any one single defect type and location. RL has been widely applied in robotics …

An Improved Foam Modeling Technique And Its Application To Petroleum Drilling And Production Practice, Yanfang Wang

LSU Doctoral Dissertations

Foam is one of the most common used multiphase fluid in Underbalanced Drilling (UBD) and Managed Pressure Drilling (MPD). Because of its low density, high capacity of lifting and carrying cuttings, low cost and compatibility with formations, foam has become more superior than the conventional drilling mud when depleted reservoir pressure, severe lost circulation, or unstable borehole are encountered. In general, the success of foam applications rely on the understanding of the fundamentals of foam rheology in downhole conditions.

Foam rheology has been studied for decades. Conventional foam rheological models such as Power Law, Bingham Plastic, Herschel-Bulkley to explain foam …

Machine Learning Based Applications For Data Visualization, Modeling, Control, And Optimization For Chemical And Biological Systems, Yan Ma

LSU Doctoral Dissertations

This dissertation report covers Yan Ma’s Ph.D. research with applicational studies of machine learning in manufacturing and biological systems. The research work mainly focuses on reaction modeling, optimization, and control using a deep learning-based approaches, and the work mainly concentrates on deep reinforcement learning (DRL). Yan Ma’s research also involves with data mining with bioinformatics. Large-scale data obtained in RNA-seq is analyzed using non-linear dimensionality reduction with Principal Component Analysis (PCA), t-Distributed Stochastic Neighbor Embedding (t-SNE), and Uniform Manifold Approximation and Projection (UMAP), followed by clustering analysis using k-Means and Hierarchical Density-Based Spatial Clustering with Noise (HDBSCAN). This report focuses …

Mixed Messages: Reading Contemporary U.S. Literature Of Biracial Girlhood, Candice Nicole Hale

LSU Doctoral Dissertations

The tragic mulatta character is no longer an accurate representation of biracial female characters in literature. This dissertation considers the vast history of the tragic mulatto genre and its tragic and mired representations of biracial women and how they are often portrayed in literature. Within a historical, legal, and political analysis, I highlight the ways perceptions, attitudes, and representations about biracial individuals have changed, so those same shifts should change in the literature. Because of the bourgeoning field of Critical Mixed Race Studies (CMRS), both scholars and authors are recasting and rewriting the narratives and discourses of mixed-race in the …

Differential Lead Accumulation In Brassica Juncea, Brassica Rapa, And Lactuca Sativa And Evaluation Of Ground Level Barriers To Prevent Lead Contamination Of Produce Grown In Raised Beds, Celine Vera Richard

LSU Master's Theses

High lead (Pb) contamination of soils is a threat to human health. Urban area soils are frequently contaminated with lead from settling of gasoline exhaust, brake dust, and lead paint on homes, old playground equipment, etc. Exposure to soil-lead occurs by ingestion or inhalation and poses an elevated risk for young children. Indirect ingestion can occur through the food chain through activities such as growing certain vegetables with an ability to tolerate and accumulate lead in edible tissues. Many university extension systems recommend growing vegetables in raised beds as a reasonable reduced risk option for avoiding lead accumulation in garden …

Conservation Easement Landowners’ Willingness To Thin The Forest: A Contingent Valuation Approach, Ana Lucia Gutierrez Castillo

LSU Master's Theses

After being subject to several decades of degradation, the bottomland hardwood (BLH) forests within the Lower Mississippi Alluvial Valley (LMAV) have undergone landscape-scale restoration regimes through conservation easement programs, such as the Wetland Reserve Program (WRP) and now the Agricultural Conservation Easement Program-Wetland Reserve Easement (ACEP-WRE). Reforested easements now require landowners' adoption of forest management practices to fulfill the program's long-term conservation goals and ecosystem services thresholds. Using a contingent valuation (CV) approach, we examine easement landowners' willingness to accept (WTA) to thin their forested easement to enhance forest health and wildlife habitat quality. Results from an interval regression model …

Experiences Of Transgender Men Who Joined National Pan-Hellenic Council Sororities Pre-Transition, Sydney Epps

LSU Doctoral Dissertations

The National Pan-Hellenic Council (NPHC) - affectionately known as The Divine Nine - are places of support and leadership development for students. However, these groups espouse traditional gender role themes that align with sexual orientation and gender rigidity. This paper explores how four NPHC members negotiate their identity as both nonbinary or transgender, and Greek. Using the narrative inquiry approach, the researcher will explore how sorority members who no longer identify as cisgender women are treated post-gender transition by other sorority members.

Fluid-Driven Fracture Initiation From Oil And Gas Wells Considering Lifetime Stresses, Andreas Michael

LSU Doctoral Dissertations

Fluid-driven fracture initiation from oil and gas wells is examined in detail. The dissertation covers three subtopics: drilling, completion (stimulations), and post-blowout capping-induced fracture initiation.

Drilling-induced tensile fractures (DITFs) are located in an azimuth orthogonal to wellbore breakouts and are observed from image logs obtained during drilling operations. Fully analytical criteria for the orientation of DITFs initiating from wells in porous, permeable media are derived considering fluid infiltration from a pressurized wellbore. DITF orientation (longitudinal or transverse-to-the-wellbore) is used to constrain the magnitude of the local maximum horizontal principal stress. The range of the possible stress states is indicated on …

The Effects Of In Utero Exposure To Aerosols Generated By Electronic Nicotine Delivery Systems In Neonatal And Adult Offspring, Kerin M. Cahill

LSU Master's Theses

Recently, electronic nicotine delivery systems (ENDS) have become increasingly popular alternatives to cigarette smoking and are perceived as “safe” substitutes. The effects that these devices have on healthy adult lungs are still not fully understood, much less the effects on vulnerable populations such as expectant mothers and neonates. In an effort to better understand the potentially detrimental outcomes that gestational usage may have on both mothers and offspring, we conducted mouse studies on in utero exposures to both, third generation (“box mod”) ENDS aerosols and fourth generation (“pod mod”) JUUL aerosols. In exposures using the box mod device, in utero …

Measurements And Mitigation Of Scattered Light Noise In Ligo, Corey Daniel Austin

LSU Doctoral Dissertations

The Advanced LIGO (aLIGO) detectors use 1064 nm lasers to measure the tiny fluctuations in spacetime that occur when gravitational waves pass through the earth. LIGO makes use of advanced coating methods and materials to limit the amount of light that scatters from the main beam, but some amount of light does scatter. This stray light can interact with surfaces inside the interferometer that are not seismically isolated and then recombine with the main beam, introducing excess noise into the gravitational wave channel. This thesis reviews the methods for modeling scattered light with ray tracing software and analytical models, for …

Molecular Mechanisms Of Boron Toxicity Tolerance In Plants, Guannan Wang

LSU Doctoral Dissertations

Boron toxicity is a worldwide agricultural problem that limits crop productivity and quality. However, our understanding on the genetic responses and adaption mechanisms to boron toxicity in plants is very limited. To address this gap in our knowledge, I compared boron stress-sensitive model, Arabidopsis thaliana and its stress-adapted relative Schrenkiella parvula to study how plants respond and adapt to excess boron at physiological, genomic, transcriptomic, and metabolic levels.

The overall project goal involved integration of multi-omics datasets to develop genome to phenome interpretations. To achieve this, I developed a python package, GOMCL, to facilitate the extraction of biologically meaningful information …

Deep-Ultraviolet Laser Ablation For Biomolecular Analysis, Oluwaremilekun Omowunmi Lawal

LSU Doctoral Dissertations

New sampling and ionization techniques were developed using a deep-ultraviolet (DUV) laser at 193 nm wavelength for analysis of large biomolecules. A micrometer spatial resolution DUV laser ablation and capture system was constructed to sample tissue biomolecules. The spot size measurements of the focused beam showed that subcellular spots with ca. 2 μm diameter can be readily achieved with this wavelength. To demonstrate the extraction of tissue biomolecules with the DUV laser, regions of tissue sections were ablated and captured for offline proteomic and genomic analysis. The proteomic studies revealed that the tissue proteins were ejected without fragmentation and that …

Sustainable Management Of Groundwater In Louisiana, Dependra Bhatta

LSU Doctoral Dissertations

The common property nature of the Mississippi River Alluvial Aquifer (MRAA) results in the formation of a cone of depression in the southern portion of the aquifer encompassing Concordia parish, Louisiana. Excessive groundwater withdrawal and the resulting cone of depression formation have caused some wells to go dry and others to be affected by saltwater intrusion. The depleting groundwater stock can be managed optimally using different groundwater management policies. The findings of this dissertation are relevant to both policymakers and researchers to understand the effects of policies to keep the aquifer sustainable.

My dissertation is written in a three-essay format. …

Structure And Dynamics Of Phospholipid Vesicles And The Dependence On Nanoscale Interactions With Molecules Of Varying Complexity, Lakshapathy Widanelage Judith Upeka De Mel

LSU Doctoral Dissertations

In this dissertation, molecular interactions and changes imposed by nano-scale structures on phospholipid vesicles were investigated. 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) large unilamellar vesicles (LUVs) were used as the model system. Understanding changes of the bilayer structure, interfacial properties, lipid dynamics, and self-assembly, allows bridging relationships between biological cell membrane structure and dynamics to cellular functionalities. For example, membrane curvature changes are linked to membrane protein functions, although the exact mechanisms of control are not yet understood. Moreover, the knowledge gained from vesicle models allows exploring novel strategies for drug delivery applications. To achieve this, DOPC LUVs were synthesized and characterized by a …

Sexually Dimorphic Oxytocin Receptor-Expressing Neurons In The Anteroventral Periventricular Nucleus Regulates Maternal Behavior, Kaustubh Sharma

LSU Doctoral Dissertations

The neurohypophysial hormone oxytocin is involved in the regulation of social behaviors, including social recognition, pair bonding, and sex-specific parental behaviors in a variety of species. Oxytocin triggers these social behaviors by binding to oxytocin receptors (OXTR) in various parts of the brain. Oxytocin-induced sex-typical behavior, therefore, suggests a sexual dimorphic distribution of OXTR in the brain. In recent years, the oxytocin system in the brain received tremendous attention as a potential pharmacological target for treatment of many psychiatric disorders, such as anxiety, autism spectrum disorders, and even sex-specific psychiatric disorder like postpartum depression (PPD). An important problem and a …

Computational Investigations Of Battery Electrolytes, Ke Li

LSU Doctoral Dissertations

In this dissertation, the structure and dynamics of battery electrolytes were investigated using atomistic molecular dynamics (MD) simulations. Battery electrolytes play a key role in transporting ions between the cathode and anode. The chemical stability and ionic conductivity of electrolytes influence battery performance. In order to design better electrolytes, one needs an understanding of the relationship between electrolyte structure, dynamics, and bulk properties. To bridge the gap between the macroscopic phenomenon and the hidden molecular physics, in the first project we focused on probing an ether-based electrolyte, chosen for its relevance in sodium-based batteries. Through studying the impact of concentration …

Typing Tornadoes By Storm Mode In The Southeast United States, Marisa R. Karpinski

LSU Master's Theses

Existing work has noted three major, radar-derived, storm modes associated with tornadoes: supercell, quasi-linear convective systems, and tropical systems. I examine the long-term frequency and seasonality of each storm mode between 1996 and 2017 in the Southeast United States. The Southeast is chosen as a focus for this work due to its well-known and unique combination of tornado vulnerability and exposure. Expanding our knowledge of the radar presentation of tornado-producing thunderstorms in this region could assist in the operational interpretation of these events. In this study, a climatology of F/EF1+ tornadoes (1996 - 2017) is generated for the study area …

Effectiveness Of Mechanical Test In Ascertaining Moisture Damage Of Asphalt Mixtures., Sanchit Sachdeva

LSU Master's Theses

Infiltrated moisture combined with repeated action of traffic and environmental loading generates distresses which adversely affect the durability of asphalt pavements. Almost 94% of states' highway agencies use either the Loaded Wheel Tracking (LWT) test or the Modified Lottman test to capture asphalt mixtures' moisture susceptibility. However, the current LWT and the modified Lottman test practice lack accuracy in relating laboratory performance to observed field performance.

The study's primary objective was to evaluate the capability of different laboratory mechanical test methods to predict moisture susceptibility of asphalt mixtures. Asphalt binder and mixture experiments were conducted to achieve the objective of …

Monitoring Of Remote Hydrocarbon Wells Using Azure Internet Of Things, Derek W. Staal

LSU Master's Theses

Remote monitoring of hydrocarbon wells is a tedious and meticulously thought out task performed to create a cyber-physical bridge between the asset and the owner. There are many systems and techniques on the market that offer this solution but due to their lack of interoperability and/or decentralized architecture they begin to fall apart when remote assets become farther away from the client. This results in extreme latency and thus poor decision making. Microsoft's Azure IoT Edge was the focus of this writing. Coupled with off-the-shelf hardware, Azure's IoT Edge services were integrated with an existing unit simulating a remote hydrocarbon …

Development Of Reduced Order Models Using Reservoir Simulation And Physics Informed Machine Learning Techniques, Mark V. Behl Jr

LSU Master's Theses

Reservoir simulation is the industry standard for prediction and characterization of processes in the subsurface. However, simulation is computationally expensive and time consuming. This study explores reduced order models (ROMs) as an appropriate alternative. ROMs that use neural networks effectively capture nonlinear dependencies, and only require available operational data as inputs. Neural networks are a black box and difficult to interpret, however. Physics informed neural networks (PINNs) provide a potential solution to these shortcomings, but have not yet been applied extensively in petroleum engineering.

A mature black-oil simulation model from Volve public data release was used to generate training data …

Well Testing Of Fracture Corridors In Naturally - Fractured Reservoirs (Nfr), Yingying Guo

LSU Master's Theses

Geological folding and/or faulting may create fractured reservoirs containing a semi-parallel system of long, sparsely - spaced fracture corridors separated by exclusion zones. Presently, the best method for detecting and assessing fracture corridor networks requires drilling, logging, and coring from horizontal wells. However, there is no method to evaluate such reservoirs by pressure testing vertical wells. Vertical wells - completed either in highly-conductive corridors (fracture wells) or in the exclusion zone (matrix wells) would respond quite differently to well testing. Therefore, their pressure response patterns can be used to identify well's placement in the corridor system and some other properties …

Quantifying Structure And Variation In Complex Phylogenetic Data, Genevieve Geraldine Mount

LSU Doctoral Dissertations

Identifying the source and structure of variation in nature is crucial to understanding fundamental aspects of evolution. Despite a recent plethora of genetic and morphological data, many interesting questions about the relationships between different groups remain unresolved. My dissertation evaluates three approaches for identifying and quantifying the variation within phylogenetic datasets. Characterizing variation within datasets and across analytical methods gives insight into biologically interesting characters, unusual evolutionary processes, and areas for model improvement.

Network-based community detection approaches offer a powerful tool to describe variation in phylogenetic signal across the genome (i.e., gene tree variation). In Chapter 2, I investigate the …

Leave It To The People: Position And Positioning Of Stakeholders In Top-Down Sustainable Development And Risk Reduction Frameworks From Global To Local Levels, Bethany Bille Garfield

LSU Doctoral Dissertations

Dissertation concerning design, contents, priorities, and outcomes of development and disaster risk reduction (DRR) global indicator frameworks. Historical review of United Nations (UN) multilateral agreements and organizational dynamics precedes analysis of indicator data reported for Sustainable Development Goal (SDG) targets shared by the 2015 Paris Agreement and Sendai Framework for Disaster Risk Reduction (SFDRR). Background on the planning of UN frameworks is considered along with results of indicator data analysis to identify actors and processes that steer the focus of frameworks hence influence selection of targets and indicators, and corresponding framework agendas. Fundamental flaws in resolution frameworks preventing global goal …

Function, History, And Ecology In The Exceptional Radiation Of Murine Rodents, Jonathan Allen Nations

LSU Doctoral Dissertations

Life’s diversity is not spread evenly across all lineages, and this unevenness is thought to be due, in part, to a few interwoven factors: biogeographic history, the evolution of successful functional traits, and the ecological opportunity these traits afford. My dissertation focuses on the evolution of a species-rich and morphologically diverse clade of mammals, the murine rodents (Murinae; Muridae; Rodentia) to address 1) morphological adaptations associated with niche transition to arboreality 2) the effect of repeated ecological transitions on murine diversification, and 3) the role of atypical ecological niches in the assembly of hyperdiverse communities. My dissertation has revealed that …