Statistics and Probability Commons^™

Field Drilling Data Cleaning And Preparation For Data Analytics Applications, Daniel Cardoso Braga

LSU Master's Theses

Throughout the history of oil well drilling, service providers have been continuously striving to improve performance and reduce total drilling costs to operating companies. Despite constant improvement in tools, products, and processes, data science has not played a large part in oil well drilling. With the implementation of data science in the energy sector, companies have come to see significant value in efficiently processing the massive amounts of data produced by the multitude of internet of thing (IOT) sensors at the rig. The scope of this project is to combine academia and industry experience to analyze data from 13 different …

Epidemiologic Evaluation Of Nhanes For Environmental Factors And Periodontal Disease, P. Emecen-Huja, H. -F. Li, J. L. Ebersole, J. Lambert, Heather M. Bush

Biostatistics Faculty Publications

Periodontitis is a chronic inflammation that destroys periodontal tissues caused by the accumulation of bacterial biofilms that can be affected by environmental factors. This report describes an association study to evaluate the relationship of environmental factors to the expression of periodontitis using the National Health and Nutrition Examination Study (NHANES) from 1999–2004. A wide range of environmental variables (156) were assessed in patients categorized for periodontitis (n = 8884). Multiple statistical approaches were used to explore this dataset and identify environmental variable patterns that enhanced or lowered the prevalence of periodontitis. Our findings indicate an array of environmental variables were …

An Interdisciplinary Weight Loss Program Improves Body Composition And Metabolic Profile In Adolescents With Obesity: Associations With The Dietary Inflammatory Index, Yasmin Alaby Martins Ferreira, Ana Claudia Pelissari Kravchychyn, Sofia De Castro Ferreira Vicente, Raquel Munhoz Da Silveira Campos, Lian Tock, Lila Missae Oyama, Valter Tadeu Boldarine, Deborah Cristina Landi Masquio, David Thivel, Nitin Shivappa, James R. Hébert, Ana R. Dâmaso

Faculty Publications

Background and Aims: The prevalence of overweight and obesity consitutes a global epidemic and it is growing around the world. Food and nutrition are essential requirements for promoting health and protecting against non-communicable chronic diseases, such as obesity and cardiovascular disease. Specific dietary components may modulate inflammation and oxidative stress in obese individuals. The Dietary Inflammatory Index (DII®) was developed to characterize the anti- and pro-inflammatory effects of individuals' diet. Few studies have investigated the role of diet-associated inflammation in adolescents with obesity. The present study aims to investigate the effects of an interdisciplinary weight loss therapy on DII scores …

Implementation Of Multivariate Artificial Neural Networks Coupled With Genetic Algorithms For The Multi-Objective Property Prediction And Optimization Of Emulsion Polymers, David Chisholm

Master's Theses

Machine learning has been gaining popularity over the past few decades as computers have become more advanced. On a fundamental level, machine learning consists of the use of computerized statistical methods to analyze data and discover trends that may not have been obvious or otherwise observable previously. These trends can then be used to make predictions on new data and explore entirely new design spaces. Methods vary from simple linear regression to highly complex neural networks, but the end goal is similar. The application of these methods to material property prediction and new material discovery has been of high interest …

Positivity-Preserving, Energy Stable Numerical Schemes For The Cahn-Hilliard Equation With Logarithmic Potential, Wenbin Chen, Cheng Wang, Xiaoming Wang, Steven M. Wise

Mathematics and Statistics Faculty Research & Creative Works

In this paper we present and analyze finite difference numerical schemes for the Cahn-Hilliard equation with a logarithmic Flory Huggins energy potential. Both first and second order accurate temporal algorithms are considered. in the first order scheme, we treat the nonlinear logarithmic terms and the surface diffusion term implicitly and update the linear expansive term and the mobility explicitly. We provide a theoretical justification that this numerical algorithm has a unique solution, such that the positivity is always preserved for the logarithmic arguments, i.e., the phase variable is always between −1 and 1, at a point-wise level. in particular, our …

Involuntary Hospitalization Among Young People With Early Psychosis: A Population-Based Study Using Health Administrative Data., Rebecca Rodrigues, Arlene G Macdougall, Guangyong Zou, Michael Lebenbaum, Paul Kurdyak, Lihua Li, Salimah Z Shariff, Kelly K Anderson

Epidemiology and Biostatistics Publications

OBJECTIVE: Early psychosis is an important window for establishing long-term trajectories. Involuntary hospitalization during this period may impact subsequent service engagement in people with newly diagnosed psychotic disorder. However, population-based studies of involuntary hospitalization in early psychosis are lacking. We sought to estimate the proportion of people aged 16 to 35 years with early psychosis in Ontario who are hospitalized involuntarily at first admission, and to identify the associated risk factors and outcomes.

METHODS: Using linked population-based health administrative data, we identified incident cases of non-affective psychosis over a five-year period (2009-2013) and followed cases for two years to ascertain …

Image-Based Modeling Of Blood Flow In Cerebral Aneurysms Treated With Intrasaccular Flow Diverting Devices, Fernando Mut, Bong Jae Chung, Jorge Chudyk, Pedro Lylyk, Ramanathan Kadirvel, David F. Kallmes, Juan R. Cebral

Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works

Modeling the flow dynamics in cerebral aneurysms after the implantation of intrasaccular devices is important for understanding the relationship between flow conditions created immediately posttreatment and the subsequent outcomes. This information, ideally available a priori based on computational modeling prior to implantation, is valuable to identify which aneurysms will occlude immediately and which aneurysms will likely remain patent and would benefit from a different procedure or device. In this report, a methodology for modeling the hemodynamics in intracranial aneurysms treated with intrasaccular flow diverting devices is described. This approach combines an image-guided, virtual device deployment within patient-specific vascular models with …

Tumor Heterogeneity As A Predictor Of Response To Neoadjuvant Chemotherapy In Locally Advanced Rectal Cancer, Alissa Greenbaum, David R. Martin, Therese J. Bocklage, Ji-Hyun Lee, Scott A. Ness, Ashwani Rajput

Pathology and Laboratory Medicine Faculty Publications

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) is the standard of care for locally advanced adenocarcinoma of the rectum, but it is currently unknown which patients have disease that will respond. This study tested the correlation between response to nCRT and intratumoral heterogeneity using next-generation sequencing assays.

PATIENTS AND METHODS: DNA was extracted from formalin-fixed, paraffin-embedded biopsy samples from a cohort of patients with locally advanced rectal adenocarcinoma (T3/4 or N1/2 disease) who received nCRT. High read-depth sequencing of > 400 cancer-relevant genes was performed. Tumor mutations and variant allele frequencies were used to calculate mutant-allele tumor heterogeneity (MATH) scores as measures of intratumoral …

Analysis Of An M/M/1 Queue With Working Vacation And Vacation Interruption, Shakir Majid, P. Manoharan

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, an M/M/1 queue with working vacation and vacation interruption is investigated. The server is supposed to interrupt the vacation and return back to the normal working period, if there are at least N customers waiting in the system at a service completion instant during the working vacation period. Otherwise, the server continues the vacation until the system is nonempty after a vacation ends or there are at least N customers after a service ends. In terms of the quasi birth and death process and matrix-geometric solution method, we obtain the distributions for the stationary queue length. Moreover, …

Performance And Economic Evaluation Of Differentiated Multiple Vacation Queueing System With Feedback And Balked Customers, Amina A. Bouchentouf, Latifa Medjahri

Applications and Applied Mathematics: An International Journal (AAM)

The present paper deals with a single server feedback queueing system under two differentiated multiple vacations and balked customers. It is assumed that the service times of the two vacation types are exponentially distributed with different means. The steady-state probabilities of the model are obtained. Some important performance measures of the system are derived. Then, a cost model is developed. Further, a numerical study is presented.

Exact Reliability For Consecutive K-Out-Of-R-From-N: F System With Equal And Unequal Components Probabilities, Yaser Amirian, Ahmad Khodadadi, Omid Chatrabgoun

Applications and Applied Mathematics: An International Journal (AAM)

A consecutive k-out-of-r-from-n: F system consists of n linear ordered components such that the system fails if and only if there exist a set of r consecutive linear component that contains at least k failed components. Consecutive k-out-of-r-from-n: F system has been considered in many fields such as reliability analysis. All recent efforts in this area have been focused on acquiring band or approximation for their reliability such that less attention has been paid to their closed form and exact reliability in the literature. In the present paper, with designing an innovative algorithm the exact reliability for extensive class of …

Transient Analysis Of A Markovian Single Vacation Feedback Queue With An Interrupted Closedown Time And Control Of Admission During Vacation, A. Azhagappan, T. Deepa

Applications and Applied Mathematics: An International Journal (AAM)

This paper analyzes the transient behavior of an M/M/1 queueing model with single vacation, feedback, interrupted closedown time and control of admission during vacation. The time-dependent system size probabilities for the proposed model are obtained using generating function in the closed form. Further, the system performance measures like mean and variance of system size are also obtained for the time-dependent case. Finally, numerical illustrations are presented to understand the effect for various system parameters.

Construction And Application Of Log-Linear Models To Assess Academic Performance, Indika R. Wickramasinghe

Applications and Applied Mathematics: An International Journal (AAM)

Log-Linear Models (LLMs) are important techniques used in categorical data analysis. Though there are some available published work about LLMs, the explanation of model building process and the theoretical background are not adequate. Furthermore, research about the application of the LLM theory and the selection procedure of the best model are handful. Therefore, this manuscript aims to fill that vacuum. At first, the construction of LLM and Hierarchical Log-Linear Models (HLLMs), a branch of LLMs are discussed in connection with both 2×2 and 2×2 ×2 contingency tables. Secondly, an application is presented to analyze the collected data set about the …

Modeling The Water-Energy-Food Nexus In Obr-E’S: The Eight (8) Coordinates, S. Sani, A. Tumushabe, M. U. Osigwe, M. Mbatudde, A. S. Hassan, M. Edson

Applications and Applied Mathematics: An International Journal (AAM)

The need to formulate quantifiers for water, energy and food (WEF) is necessary sequel to conservation issues worldwide. Existing methodologies on the WEF nexus appear less fitting in sustainability arguments because of incompleteness. This article analyzes the WEF nexus in open but restricted environments (ObR-E’s) with completeness assumption in form of the known inter-intra dependence of nexus elements for sustainability and better conservation practice. The analysis leads to the discovery of the Jalingo equation whose any non simplistic solution is a solution to the WEF problem in some ObR-E’s world wide. It is important to seek other non simplistic solutions …

Analysis Of M[X1],M[X2]/G1,G2/1 Retrial Queueing System With Priority Services, Working Breakdown, Collision, Bernoulli Vacation, Immediate Feedback, Starting Failure And Repair, G. Ayyappan, P. Thamizhselvi, B. Somasundaram

Applications and Applied Mathematics: An International Journal (AAM)

This paper considers an M^[X₁] , M^[X₂] /G1,G2/1 general retrial queueing system with priority services. Two types of customers from different classes arrive at the system in different independent compound Poisson processes. The server follows the non-pre-emptive priority rule subject to working breakdown, Bernoulli vacation, starting failure, immediate feedback, collision and repair. After completing each service, the server may go for a vacation or remain idle in the system. The priority customers who find the server busy are queued in the system. If a low-priority customer finds the server busy, he is routed to …

A Note On Asymptotic Normality Of A Copula Function In Regression Model, Khadidja Sabri, Mustapha Meghnafi, Abbes Rabhi, Djamila Bennafla

Applications and Applied Mathematics: An International Journal (AAM)

Over the last decade, there has been significant and rapid development of the theory of copulas. Much of the work has been motivated by their applications to stochastic processes, economics, risk management, finance, insurance, the environment (hydrology, climate, etc.), survival analysis, and medical sciences. In many statistical models. The copula approach is a way to solve the difficult problem of finding the whole bivariate or multivariate distribution. In this paper, we give the asymptotic normality of the copulas function in a regression model.

Study Of Specially And Temporally Dependent Adsorption Coefficient In Heterogeneous Porous Medium, Dilip K. Jaiswal, Gulrana _

Applications and Applied Mathematics: An International Journal (AAM)

One-dimensional advection-dispersion equation (ADE) is studied along unsteady longitudinal flow through a semi-infinite heterogeneous medium. Adsorption coefficient is considered temporally and spatially–dependent function i.e., expressed in degenerate form. The dispersion parameter is considered as inversely proportional to adsorption coefficient. The input source is of pulse type. The Laplace Transformation Technique (LTT) is used to obtain the analytical solution by introducing certain new independent variables through separate transformations. The effects of adsorption, heterogeneity and unsteadiness are investigated and discussed with the help of various graphs.

The Martingale Approach To Financial Mathematics, Jordan M. Rowley

Master's Theses

In this thesis, we will develop the fundamental properties of financial mathematics, with a focus on establishing meaningful connections between martingale theory, stochastic calculus, and measure-theoretic probability. We first consider a simple binomial model in discrete time, and assume the impossibility of earning a riskless profit, known as arbitrage. Under this no-arbitrage assumption alone, we stumble upon a strange new probability measure Q, according to which every risky asset is expected to grow as though it were a bond. As it turns out, this measure Q also gives the arbitrage-free pricing formula for every asset on our market. In …

Optimizing Electrospun Ceramic Nanofiber Strength Through Two-Step Sintering, Michael Ross

Materials Engineering

Two-step sintering (TSS) consists of a high-temperature step and immediate cooling to a sintering temperature for an extended sintering time, where grain growth is suppressed by severe densification during the high-temperature step. TSS is adopted to enhance mechanical properties of electrospun ceramic nanofibers (CNFs), a class of porous ceramics used for environmental remediation, optoelectronics, and filtration. PVP and Ga(NO₃)₃ nanofiber mesh, provided by Lawrence Livermore National Laboratory, was shaped, oxidized, and two-step sintered to form a nanocrystalline β-Ga₂O₃ CNF tube using a high-temperature step of 1,000^oC. Sintering temperatures and times varied from …

Cs + Sociology: Using Big Data To Identify And Understand Educational Inequality In America (1), Joseph Cleary, Elin Waring

Open Educational Resources

This is the first of two lessons/labs for teaching and learning of computer science and sociology. Either and be used on their own or they can be used in sequence, in which case this should be used first.

Students will develop CS skills and behaviors including but not limited to: learning what an API is, learning how to access and utilize data on an API, and developing their R coding skills and knowledge. Students will also learn basic, but important, sociological principles such as how poverty is related to educational opportunities in America. Although prior knowledge of CS and sociology …