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Modelling Hydraulic Fracturing Propagation In Heterogeneous Reservoirs Using Cohesive Zone Methods, Miguel Alejandro Gonzalez-Chavez

LSU Doctoral Dissertations

The recent success in exploiting low permeability shale reservoirs has heavily relied on hydraulic fracturing to produce hydrocarbons economically in disadvantaged reservoir conditions. Although horizontal drilling significantly increases the contact area between the wellbore and the reservoir, the objective of hydraulic fracturing is set on creating further expanded conductive flow paths into the reservoir. This research uses cohesive zone method to numerically simulate hydraulic fracture propagation in the presence of natural fractures in two- and three-dimensional model. The Cohesive element approach limits fracture propagation to some predefined paths. However, in highly fractured formations since hydraulic fractures are growing through a …

Hamiltonian Formulation For Wave-Current Interactions In Stratified Rotational Flows, Adrian Constantin, Rossen Ivanov, Calin-Iulian Martin

Articles

We show that the Hamiltonian framework permits an elegant formulation of the nonlinear governing equations for the coupling between internal and surface waves in stratified water flows with piecewise constant vorticity.

Interactions Among Hydrology, Sediment And Vegetation In Accreting Wax Lake Delta: Physical And Biogeochemical Implications For Coastal Louisiana Restoration, Courtney Erin Elliton

LSU Master's Theses

River discharge pulses, wind, waves, tides, and the presence of dense vegetation are factors that interact and regulate the transport and retention of sediment in coastal regions. In particular, vegetation structural and physiognomic traits promote fine sediment trapping during tidal and river flow, maintaining the balance between soil elevation and relative sea level rise on coastline stability and land building. Mike Island, located within Wax Lake Delta, Louisiana, USA, is part of a deltaic system created by a man-made freshwater diversion (1941) and one of few coastal areas where land is expanding in coastal Louisiana as result of pulsing river …

On The N-Wave Equations With Pt-Symmetry, Vladimir Gerdjikov, Georgi Grahovski, Rossen Ivanov

Articles

We study extensions of N-wave systems with PT-symmetry. The types of (nonlocal) reductions leading to integrable equations invariant with respect to P- (spatial reflection) and T- (time reversal) symmetries is described. The corresponding constraints on the fundamental analytic solutions and the scattering data are derived. Based on examples of 3-wave (related to the algebra sl(3,C)) and 4-wave (related to the algebra so(5,C)) systems, the properties of different types of 1- and 2-soliton solutions are discussed. It is shown that the PT symmetric 3-wave equations may have regular multi-soliton solutions for some specific choices of their parameters.

The Dynamics Of Flat Surface Internal Geophysical Waves With Currents, Alan Compelli, Rossen Ivanov

Articles

A two-dimensional water wave system is examined consisting of two discrete incompressible fluid domains separated by a free common interface. In a geophysical context this is a model of an internal wave, formed at a pycnocline or thermocline in the ocean. The system is considered as being bounded at the bottom and top by a flatbed and wave-free surface respectively. A current profile with depth-dependent currents in each domain is considered. The Hamiltonian of the system is determined and expressed in terms of canonical wave-related variables. Limiting behavior is examined and compared to that of other known models. The linearised …

Unique Characterization Of Materials With Memory, John Murrough Golden

Articles

In general, materials with linear memory constitutive relations are characterized by a relaxation function. This leads to a situation where the free energy for most materials with memory is not unique. There is a convex set of free energy functionals with a minimum and a maximum element. An alternative procedure is proposed which characterizes a material by the kernel of the rate of dissipation functional. Using some recent results, we find that a unique free energy and relaxation function may then be deduced. An example is given for discrete spectrum materials. Also, the new results are used to show that …

An Investigation Of The Generalizability Of Buoyancy From Academics To Athletics, Jackie Rae Victoriano

LSU Master's Theses

Buoyancy, the ability of an individual to handle everyday setbacks, has been applied successfully to academics, and has implications for performance and well-being. The purpose of this investigation was to determine if the concept of buoyancy can be successfully applied to the domain of sports (i.e., athletic buoyancy). This study sought to examine the relationship between academic and athletic buoyancy, as well as the efficacy of five sport-oriented predictors (5Cs), confidence, coordination (planning), commitment, composure (anxiety), and control, on both athletic and academic buoyancy. Sport club athletes (N = 285) aged 18 to 31 years completed a one-time survey assessing …

Testing The Asset-Based Theory Of American Social Welfare: Does A Future-Orientation Mediate The Relationship Between Asset-Ownership And Financial Responsibility?, Louie Fletcher Bickham Iii

LSU Doctoral Dissertations

The ownership of financial assets protects American households from experiencing the struggles of income poverty. The asset-based theory of American social welfare, which was conceptualized by Professor Michael Sherraden in 1991 and amended in 2001 by other scholars, posited that social welfare programs diminish the prevalence of poverty by enabling households to save funds to purchase assets. This theory has been scantly tested—especially among American households—despite a great amount of funds being invested into programs designed to help low-income American households to build assets. The only previous study that examined the intermediary role of future-orientations on the effect of asset-ownership …

Comparison Of Advanced Radiotherapy Techniques For Post-Mastectomy Breast Cancer Patients, David Elward Heins

LSU Master's Theses

Purpose: To determine if bolus electron conformal therapy (BECT) combined with volumetric modulated arc therapy (VMAT) and flattening filter free volumetric modulated arc therapy (FFFVMAT (6x and 10x)) can maintain equal or better dose coverage than standard volumetric modulated arc therapy (VMAT) while reducing doses to organs at risk (OARs). Methods: BECT+VMAT, FFFVMAT (6x and 10x), and VMAT treatment plans were produced for ten post-mastectomy radiotherapy (PMRT) patients previously treated at our clinic. The treatment plans were created on a commercially available treatment planning system (TPS) and all completed treatment plans were reviewed and approved by a radiation oncologist. The …

Effect Of Timing Of Shade On Growth, Development, Physiology, And Fruiting Of A Primocane Fruiting Blackberry In A Controlled Environment, Olivia C. Caillouet, Curt C. Rom, Jason Mcafee, Luke Freeman, Heather Friedrich

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Primocane blackberry production in the upper south is limited by high temperatures during the bloom and early fruiting period, resulting in poor fruit set and poor fruit quality. Shade may have the potential to delay bloom and flowering to a more favorable season. A greenhouse study was established to evaluate the effects of shade on primocane blackberry growth, physiology, and fruiting. Single rooted plants of ‘Prime-Ark® 45’ were planted in 12-liter pots and grown in a greenhouse at the University of Arkansas System Division of Agriculture, Agriculture Research and Extension Center, Fayetteville, Arkansas. At approximately 0.25 m in height, one …

The Effects Of Shade On Primocane Fruiting Blackberries In The Field, Olivia C. Caillouet, Curt C. Rom, Jason Mcafee, Luke Freeman, Heather Friedrich

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Primocane fruiting blackberry production in Arkansas is limited by heat during the flowering and early fruiting season. Shade could be used to delay flowering and fruiting to more favorable growth period. This study was designed to test three levels of shade (0% [control], 30% and 50% shading) applied at three times during the growing season that examined the growth, development, physiology of flowering, and fruiting of ‘Prime-Ark® 45’ blackberries. The seven treatments were as follows: 1) an untreated control (CK), 2) early shade 30% (ES30), mid shade 30% (MS30), 4) late shade 30% (LS30), 5) early shade 50% (ES50), 6) …

Optimal Configuration Of Inspection And Rework Stations In A Multistage Flexible Flowline, Md. Shahriar Jahan Hossain

LSU Master's Theses

Inspection and rework are two important issues of quality control. In this research, an N-stage flowline is considered to make decisions on these two issues. When defective items are detected at the inspection station the items are either scrapped or reworked. A reworkable item may be repaired at the regular defect-creating workstation or at a dedicated off-line rework station. Two problems (end-of-line and multistage inspections) are considered here to deal with this situation. The end-of-line inspection (ELI) problem considers an inspection station located at the end of the line while the multistage inspection (MSI) problem deals with multiple in-line inspection …

A Study Of Fpga Resource Utilization For Pipelined Windowed Image Computations, Aswin Vijaya Varma

LSU Master's Theses

In image processing operations, each pixel is often treated independently and operated upon by using values of other pixels in the neighborhood. These operations are often called windowed image computations (or neighborhood operations). In this thesis, we examine the implementation of a windowed computation pipeline in an FPGA-based environment. Typically, the image is generated outside the FPGA environment (such as through a camera) and the result of the windowed computation is consumed outside the FPGA environment (for example, in a screen for display or an engine for higher level analysis). The image is typically large (over a million pixels 1000×1000 …

The Effects Of Carbon Nanotubes On Cells In A Synthetic Oxygen Carrier Enriched Alginate Scaffold, Joshua Paul Tate

LSU Master's Theses

Abstract Huge progress has been made in the development of three dimensionally printed tissue structures. With the use of cells, three dimensional printers, and CAD drawing software, donor identical structures can be fabricated. However, cell scaffolds currently lack significant mechanical integrity which can result in reduced cellular survival, attachment, and nutrient delivery. For this reason, multiple strategies have been developed to increase and improve mechanical stability within engineered constructs without having to sacrifice cell viability. The hypothesis of this paper was that incorporating Perfluorotributylamine (PFTBA), a greenhouse gas, with single walled carbon nanotubes (SWCNT), a allotrope of carbon with a …

Twisted Reflection Positivity, Mostafa Ahmad Hayajneh

LSU Doctoral Dissertations

Reflection positivity has several applications in both mathematics and physics. For example, reflection positivity induces a duality between group representations. In this thesis, we coin a new definition for a new kind of reflection positivity, namely, twisted reflection positive representation on a vector space. We show that all of the non-compactly causal symmetric spaces give rise to twisted reflection positive representations. We discover examples of twisted reflection positive representations on the sphere and on the Grassmannian manifold which are not unitary, namely, the generalized principle series with the Cosine transform as an intertwining operator. We give a direct proof for …

Detection Of Antibiotic Resistance Clostridium Difficile In Lettuce, Yi Han

LSU Master's Theses

Clostridium difficile (C. difficile) is regarded as the major cause of infectious diarrhea in humans after antimicrobial treatment. C. difficile has been reported to be widely isolated from food animals and meat. The main purpose of this study was to characterize C. difficile isolates from retail fresh vegetable (lettuce), test the antibiotic-resistance property using five common clinical-selected antibiotics (metronidazole, vancomycin, clindamycin, erythromycin, and cefotaxime). Lettuces (grown in California, Arkansas, and Louisiana) were purchased from retail stores. Toxigenic C. difficile was isolated from 13.8% (41/297) of the lettuce samples. Among the toxigenic isolates, 82.9% (34/41) only produce toxin B, and 17.1% …

Spectral Properties Of Photonic Crystals: Bloch Waves And Band Gaps, Robert Paul Viator Jr

LSU Doctoral Dissertations

The author of this dissertation studies the spectral properties of high-contrast photonic crystals, i.e. periodic electromagnetic waveguides made of two materials (a connected phase and included phase) whose electromagnetic material properties are in large contrast. A spectral analysis of 2nd-order divergence-form partial differential operators (with a coupling constant k) is provided. A result of this analysis is a uniformly convergent power series representation of Bloch-wave eigenvalues in terms of the coupling constant k in the high-contrast limit k -> infinity. An explicit radius of convergence for this power series is obtained, and can be written explicitly in terms of the …

Meeting Biopsychosocial Needs Of Individuals With Histories Of Multiple Adverse Childhood Experiences, Christine G. Morgan

LSU Master's Theses

According to Felitti and colleagues (1998), a significant portion of the general population has been exposed to adverse childhood experiences (ACEs) with subsequent and persistent, dose-related, negative consequences to physical and mental health. Debilitating disturbances to biopsychosocial well-being are significant and frequently lead to fatality in adulthood. After reviewing the prevalence and severity of ACEs, this thesis presents an overview of the literature outlining the biological, social, and psychological factors contributing to the development and progression of disease in the brain and body. Additionally, current trauma-informed interventions are summarized. Three experienced clinicians share practical advice for implementing evidence-based, trauma-informed mental …

Rapid Cooling Of Eastern Oysters (Crassostrea Virginica) Using An On-Board Icing Unit To Slow The Growth Of Vibrio Vulnificus And Vibrio Parahaemolyticus, Melody Amber Thomas

LSU Master's Theses

Oyster harvesting is a major industry along the Eastern and Gulf coasts of the United States. Eastern oysters (Crassostrea virginica) spawn when the waters start to warm between May and October in the Gulf of Mexico. The warmer temperature creates a problem with an increase of bacteria. The two major bacteria affecting the oyster industry are Vibrio vulnificus and Vibrio parahaemolyticus. These bacteria are the leading causes of seafood-borne illnesses in the United States. This increase of V. vulnificus and V. parahaemolyticus has led to stricter time/temperature requirements for harvesting oysters. The regulations are not plausible for smaller vessels too …

The Role Of Upper Ocean Heat Content And Sea Surface Temperature On Northeast Pacific Hurricane Evolution During Average And Active Years, Victoria Lauren Ford

LSU Master's Theses

Upon comparison to typical neutral-ENSO conditions in the Northeast Pacific Ocean, the 2014 hurricane season has been identified as highly anomalous in both tropical cyclone frequency and intensity. This thesis seeks to investigate the influence of sea surface temperatures (SSTs) and upper ocean heat content (UOHC), defined as the excess of heat present above 26°C, upon the upper ocean thermal structure, mesoscale features, and anomalies that led to an active hurricane season in the Northeast Pacific. The 2012 Northeast Pacific hurricane season was selected as a ‘normal’ season to fully quantify the anomalous 2014 hurricane season. Data sets utilized in …

An Examination Of The Lived Experiences Of United States Military Veterans Who Have Been Diagnosed With Psychological Inflictions Of War Who Have Utilized Equine Assisted Therapy, Thomas Frederick Banner

LSU Doctoral Dissertations

As the result of multiple psychological conditions that are inflicted by war, the need for veterans’ well-being is ever evident. “PTSD changes the body’s response to stress, often making it difficult for PTSD victims to live their lives as they normally would” (Stokes, 2013, p. 1). It is possible to touch individuals who do not react to traditional therapy with a different type of therapy. It is recommended that veterans besieged with these same symptoms could benefit from therapy with animals. Renson (2010) concluded that animals have delivered numerous benefits to people using therapy. The benefits that animals offer in …

Effect Of Tillage And Fertilization On Agronomics And Nutrient Uptake Of Sweet Sorghum And Soil Test Extractable P And K After Four Years Of A Monocrop Production System, Jifeng Li

LSU Master's Theses

Sweet sorghum [Sorghum bicolor (L.) Moench] (SS) has been grown in the southern United States to produce syrup for many years. There is an interest in SS as a biofuel feedstock due to its high sugar content and high total biomass. Currently, little is known about the nutrient demand for SS or how it responds to tillage and fertilization. The objectives of this study were to: 1) evaluate the effects of tillage and phosphorus (P) and potassium (K) fertilization on SS agronomics, 2) evaluate nitrogen (N), P, and K uptake and nutrient partitioning in SS, 3) determine P and K …

Examining Teachers' Attitudes On The Read 180 Program In Six Southern Louisiana Schools, Shanell Dowling

LSU Master's Theses

The purpose of this research was to examine teachers’ attitudes on the READ 180 scripted curriculum in six Southern Louisiana schools. The researcher wanted to evaluate the factors that impact teachers’ attitudes toward using the READ 180 scripted curriculum in today’s classrooms. The study focused on teachers’ feelings, advantages and disadvantages of the READ 180 program, and how the program is being implemented. To discover teachers’ experiences with the READ 180 program the researcher conducted audio-recorded teacher interviews, recorded field notes during classroom observations, and collected documents from participating teachers. This study was conducted over the course of four months …

Nucleobindin-2: A Novel Regulator Of Immune-Metabolic Interactions, Anthony Ravussin

LSU Doctoral Dissertations

Over the past half century, obesity has become a widespread concern to human health. Obesity is defined as having a body mass index above 30 and is accompanied by altered metabolic physiology. Obesity is one of the leading causes of mortality in the United States and in the world. The prevalence of obesity has increased over the past few decades. High body fat in adipose, excess calorie intake, low aerobic fitness are all associated with the comorbidities of obesity. Recently, an emphasis has been given to increased leukocytes in adipose tissue and the resulting low-grade systemic inflammation on the development …

Peptidomimetic Polymers: Advances In Monomer Design And Polymerization Methods, Brandon Andrew Chan

LSU Doctoral Dissertations

This work is focused on the design, synthesis and characterization of polypeptide and polypeptoid polymers. The former are composed of amino acid repeat units and possess intramolecular hydrogen bonding interactions allowing for the self-assembly into well-defined secondary structures (e.g. α-helix). Polypeptoids are based on N-alkyl substituted glycine and lack intramolecular hydrogen bonding interactions, resulting in enhanced proteolytic stability and thermal processability. Physicochemical properties of polypeptoids are strongly dependent on the side chain structures, allow for control of the solubility, crystallinity, and conformation of the polymers. Well-defined polypeptides and polypeptoids are synthesized by the ring-opening polymerization (ROP) of their corresponding N-carboxyanhydride …

Electoral Determinants Of State Repression In Democracies, Tonya Kenny

LSU Master's Theses

One of the most consistent findings, to date, in the human rights literature asserts that democracy decreases the likelihood of state repression. Several studies have noted the pacifying effects of democratic norms, competitive elections, and institutional checks on the executive as aspects that make democracies less repressive. However, the basic dichotomous measures that are commonly used in the literature only capture the presence or absence of these democratic characteristics and cannot account for the variation that exists between countries within these democratic institutions. In this paper, I suggest that electoral outcomes resulting from variation in institutional choice may have certain …

Advances In Quantum Metrology: Continuous Variables In Phase Space, Bryan Tomas Gard

LSU Doctoral Dissertations

This dissertation serves as a general introduction to Wigner functions, phase space, and quantum metrology but also strives to be useful as a how-to guide for those who wish to delve into the realm of using continuous variables, to describe quantum states of light and optical interferometry. We include many of the introductory elements one needs to appreciate the advantages of this treatment as well as show many examples in an effort to make this dissertation more friendly. In the initial segment of this dissertation, we focus on the advantages of Wigner functions and their use to describe many quantum …

A Book Club For Children With Autism Spectrum Disorder, Elizabeth Ann Kosmicki

Honors Program Theses

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by difficulties with social communication and interaction, as well as repetitive behaviors, interests, or activities. Individuals with ASD are also known to struggle with reading comprehension. Difficulties in social communication and interaction may lead to depression, while poor literacy skills may result in unemployment and poverty. Because book clubs target social communication and interaction, as well as reading comprehension, they may be beneficial for individuals with ASD. Indeed, some evidence already exists to support this belief. Through literature review of book clubs in general, currently existing book clubs and information on …

Motion Virtual Manipulatives In The Elementary Math Classroom, Cole Boudreau

Honors Program Theses

An application was developed to aid in teaching core mathematical concepts to kindergarten through third grade students. This software would be available at minimal cost when compared to current alternatives, and was designed specifically with effectiveness in mind. A framework called motion virtual manipulatives was developed, allowing to the creation of a touch-based application on any flat wall or surface. The application developed implemented multiple forms of manipulatives, each designed to allow for ease-of-use. The application is planned to be tested in classrooms with the aid of a secondary application developed to analyze the use of this project’s application.

Keywords: …

Equitable Discourse In Middle School Mathematics Classrooms: With Emphasis On Girls And The Mathematically Gifted, Merci F. Day

Honors Program Theses

Discourse is a tool used by mathematics teachers to help deepen mathematical understanding and build students’ mathematical identities. Teachers face the challenge of establishing and maintaining classroom norms that help discussions deepen mathematical understanding as well as meet the needs of all of their students. The researcher focused on what girls and the mathematically gifted need from discourse and how to create an equitable environment for all students. Girls need to be given equitable opportunities to voice their thoughts, and mathematically gifted students need to be adequately challenged, not just given more work. The researcher interviewed three teachers who employ …