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Full-Text Articles in Physical Sciences and Mathematics

Progression Magazine, 2016 Spring, Coastal Carolina University May 2016

Progression Magazine, 2016 Spring, Coastal Carolina University

Progression Magazine

Magazine of the College of Science at Coastal Carolina University.


Place Events 2015-2016, Place May 2016

Place Events 2015-2016, Place

PLACE Historical Documents

This document describes PLACE events at Linfield College for 2015-2016.


Phosphonium/Phosphate Ionic Liquids As Lubricant Additives: The Synthesis And Testing Of Six Novel Ils, Matthew Scott Welmers May 2016

Phosphonium/Phosphate Ionic Liquids As Lubricant Additives: The Synthesis And Testing Of Six Novel Ils, Matthew Scott Welmers

Graduate Theses - Chemistry and Biochemistry

In this study, ionic liquids (ILs) are defined as ionic materials with a melting temperature >100oC. ILs are characterized by their organic moieties which prevent crystallization, forcing the liquid phase. ILs are desirable as lubricant additives because of their ability to be fine-tuned by varying the identity of the cation/anion as well as the various organic functional moieties therein. Several novel phosphonium/phosphate ILs have been successfully synthesized via a simple, straightforward process. In this work a series of symmetric and asymmetric anionic phosphodiesters are developed and coordinated with two asymmetric alkyl phosphonium cations. These ILs are tested in SAE 10W30 …


Development And Validation Of An Empirical Temperature-Dependent Voltage Model For Diode Laser Characterization, Grant Matthew Brodnik May 2016

Development And Validation Of An Empirical Temperature-Dependent Voltage Model For Diode Laser Characterization, Grant Matthew Brodnik

Graduate Theses - Physics and Optical Engineering

This work investigates the effects of temperature on the operation and performance of indium-phosphide (InP) based high-power broad-area laser (BAL) diodes operating in the eye-safe regime (1.5 μm – 2.0 μm). Low temperature (-80C to 0C) operation using a cryogenically cooled system enables investigation of temperature-dependent parameters such as threshold current, slope efficiency, diode voltage, and power conversion efficiency (PCE) of devices. Building upon established empirical models that describe threshold current and slope efficiency as functions of temperature, a key additional parametric model is developed to describe diode voltage incorporating a temperature dependence. With the inclusion of this temperature-dependent voltage …


Patterns And Sources Of Anthropogenic Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah J. Wolfe May 2016

Patterns And Sources Of Anthropogenic Contaminants In The Otter Creek Watershed, Madison County, Kentucky, Elijah J. Wolfe

EKU Faculty and Staff Scholarship

Stream systems are often affected by anthropogenic activities that affect water quality and stream ecosystems. Land use typically determines the type and quantity of anthropogenic contaminants entering natural waters. The Otter Creek watershed (170 km2; Madison County, Kentucky) consists predominantly of pasture and rural housing, with some cropland. The basin also receives runoff from the town of Richmond and a sewage treatment plant operates within the watershed. We measured concentrations of nutrients (phosphate, ammonium, nitrate) and fecal microbes to discover levels of anthropogenic contaminants affecting water quality and to identify contaminant sources.

We sampled 4 times in the …


Bending Loss Mitigation By Surface Plasmon Resonance, Daniel Steven Spoor May 2016

Bending Loss Mitigation By Surface Plasmon Resonance, Daniel Steven Spoor

Graduate Theses - Physics and Optical Engineering

Surface plasmon resonance can be used to confine a wave within a thin metal film. The resultant wave is very well-confined by the extreme refractive index difference between the metal and the ambient medium. Such confinement can be used to guide waves under extreme conditions such as subwavelength channels or through extremely tight bends where radiation losses would normally dissipate the wave.

A nichrome thin film was deposited and etched as a shadow alongside a series of multi-mode SU-8 slab waveguides with extremely sharp angled bends. Light from a Helium-Neon laser was coupled into these waveguides and the power transmitted …


Importance Of Grad-Shafranov Re-Solves Towards Accurately Modeling An Iter Equilibrium In Nimrod, Joseph Jepson May 2016

Importance Of Grad-Shafranov Re-Solves Towards Accurately Modeling An Iter Equilibrium In Nimrod, Joseph Jepson

Physics Capstone Projects

In the year 2013, the United States produced a total of around 4 billion kWh of electricity for its energy consumption needs [1]. Around 67% of this was from fossil fuels (coal, natural gas, petroleum). To produce energy of this scope requires vast amounts of fuel, at great expense (the EPA estimates that around $29 billion was spent on fossil fuel electric energy production during 2013) [1]. Fusion energy may provide a viable alternative energy source to fossil fuels. As a comparison, producing the US fossil fuel electric energy for 2013 solely from coal would require about 468 billion kg …


Application Of Esscher Transformed Laplace Distribution In Microarray Gene Expression Data, Shanmugasundaram Devika, Sebastian George, Lakshmanan Jeyaseelan May 2016

Application Of Esscher Transformed Laplace Distribution In Microarray Gene Expression Data, Shanmugasundaram Devika, Sebastian George, Lakshmanan Jeyaseelan

Journal of Modern Applied Statistical Methods

Microarrays allow the study of the expression profile of hundreds to thousands of genes simultaneously. These expressions could be from treated samples and the healthy controls. The Esscher transformed Laplace distribution is used to fit microarray expression data as compared to Normal and Laplace distributions. The Maximum Likelihood Estimation procedure is used to estimate the parameters of the distribution. R codes are developed to implement the estimation procedure. A simulation study is carried out to test the performance of the algorithm. AIC and BIC criterion are used to compare the distributions. It is shown that the fit of the Esscher …


The Goldilocks Dilemma: Impacts Of Multicollinearity -- A Comparison Of Simple Linear Regression, Multiple Regression, And Ordered Variable Regression Models, Grayson L. Baird, Stephen L. Bieber May 2016

The Goldilocks Dilemma: Impacts Of Multicollinearity -- A Comparison Of Simple Linear Regression, Multiple Regression, And Ordered Variable Regression Models, Grayson L. Baird, Stephen L. Bieber

Journal of Modern Applied Statistical Methods

A common consideration concerning the application of multiple linear regression is the lack of independence among predictors (multicollinearity). The main purpose of this article is to introduce an alternative method of regression originally outlined by Woolf (1951), which completely eliminates the relatedness between the predictors in a multiple predictor setting.


Solution To The Multicollinearity Problem By Adding Some Constant To The Diagonal, Hanan Duzan, Nurul Sima Binti Mohamaed Shariff May 2016

Solution To The Multicollinearity Problem By Adding Some Constant To The Diagonal, Hanan Duzan, Nurul Sima Binti Mohamaed Shariff

Journal of Modern Applied Statistical Methods

Ridge regression is an alternative to ordinary least-squares (OLS) regression. It is believed to be superior to least-squares regression in the presence of multicollinearity. The robustness of this method is investigated and comparison is made with the least squares method through simulation studies. Our results show that the system stabilizes in a region of k, where k is a positive quantity less than one and whose values depend on the degree of correlation between the independent variables. The results also illustrate that k is a linear function of the correlation between the independent variables.


Symmetric Variants Of Logistic Smooth Transition Autoregressive Models: Monte Carlo Evidences, Olaoluwa S. Yaya, Olanrewaju I. Shittu May 2016

Symmetric Variants Of Logistic Smooth Transition Autoregressive Models: Monte Carlo Evidences, Olaoluwa S. Yaya, Olanrewaju I. Shittu

Journal of Modern Applied Statistical Methods

The Smooth Transition Autoregressive (STAR) models are becoming popular in modeling economic and financial time series. The asymmetric type of the model is the Logistic STAR (LSTAR) model, which is limited in its applications as a result of its asymmetric property, which makes it suitable for modelling specific macroeconomic time series. This study was designed to develop the Absolute Error LSTAR (AELSTAR) and Quadratic LSTAR (QLSTAR) models for improving symmetry and performance in terms of model fitness. Modified Teräsvirta’s Procedure (TP) and Escribano and Jordá's Procedure (EJP) were used to test for nonlinearity in the series. The performance of the …


Factorial Invariance Testing Under Different Levels Of Partial Loading Invariance Within A Multiple Group Confirmatory Factor Analysis Model, Brian F. French, Holmes Finch May 2016

Factorial Invariance Testing Under Different Levels Of Partial Loading Invariance Within A Multiple Group Confirmatory Factor Analysis Model, Brian F. French, Holmes Finch

Journal of Modern Applied Statistical Methods

Scalar invariance in factor models is important for comparing latent means. Little work has focused on invariance testing for other model parameters under various conditions. This simulation study assesses how partial factorial invariance influences invariance testing for model parameters. Type I error inflation and parameter bias were observed.


Jmasm36: Nine Pseudo R^2 Indices For Binary Logistic Regression Models (Spss), David A. Walker, Thomas J. Smith May 2016

Jmasm36: Nine Pseudo R^2 Indices For Binary Logistic Regression Models (Spss), David A. Walker, Thomas J. Smith

Journal of Modern Applied Statistical Methods

This syntax program is an applied complement to Veall and Zimmermann (1994), Menard (2000), and Smith and McKenna (2013) and produces nine pseudo R2 indices, not readily accessible in statistical software such as SPSS, which are used to describe the results from binary logistic regression analyses.


A Spatial Analytical Framework For Examining Road Traffic Crashes, Grace O. Korter May 2016

A Spatial Analytical Framework For Examining Road Traffic Crashes, Grace O. Korter

Journal of Modern Applied Statistical Methods

A number of different modeling techniques have been used to examine road traffic crashes for analytic and predictive purposes. Map-based spatial analysis is introduced. Applications are given which show the power in a combination of existing exploratory and statistical methods.


Jmasm38: Confidence Intervals For Kendall's Tau With Small Samples (Spss), David A. Walker May 2016

Jmasm38: Confidence Intervals For Kendall's Tau With Small Samples (Spss), David A. Walker

Journal of Modern Applied Statistical Methods

A syntax program, not readily expedient in statistical software such as SPSS, is provided for an application of confidence interval estimates with Kendall’s tau-b for small samples.


An Evaluation Of Pareto, Lognormal And Pps Distributions: The Size Distribution Of Cities In Kerala, India, Christopher A. Vallabados, Subbarayan A. Arumugam May 2016

An Evaluation Of Pareto, Lognormal And Pps Distributions: The Size Distribution Of Cities In Kerala, India, Christopher A. Vallabados, Subbarayan A. Arumugam

Journal of Modern Applied Statistical Methods

The Pareto-Positive Stable (PPS) distribution is introduced as a new model for describing city size data of a region in a country. The PPS distribution provides a flexible model for fitting the entire range of a set of city size data and the classical Pareto and Zipf distributions are included as a particular case.


Determination Of Optimal Tightened Normal Tightened Plan Using A Genetic Algorithm, Sampath Sundaram, Deepa S. Parthasarathy May 2016

Determination Of Optimal Tightened Normal Tightened Plan Using A Genetic Algorithm, Sampath Sundaram, Deepa S. Parthasarathy

Journal of Modern Applied Statistical Methods

Designing a tightened normal tightened sampling plan requires sample sizes and acceptance number with switching criterion. An evolutionary algorithm, the genetic algorithm, is designed to identify optimal sample sizes and acceptance number of a tightened normal tightened sampling plan for a specified consumer’s risk, producer’s risk, and switching criterion. Optimal sample sizes and acceptance number are obtained by implementing the genetic algorithm. Tables are reported for various choices of switching criterion, consumer’s quality level, and producer’s quality level.


Model-Based Outlier Detection System With Statistical Preprocessing, D. Asir Antony Gnana Singh, E. Jebalamar Leavline May 2016

Model-Based Outlier Detection System With Statistical Preprocessing, D. Asir Antony Gnana Singh, E. Jebalamar Leavline

Journal of Modern Applied Statistical Methods

Reliability, lack of error, and security are important improvements to quality of service. Outlier detection is a process of detecting the erroneous parts or abnormal objects in defined populations, and can contribute to secured and error-free services. Outlier detection approaches can be categorized into four types: statistic-based, unsupervised, supervised, and semi-supervised. A model-based outlier detection system with statistical preprocessing is proposed, taking advantage of the statistical approach to preprocess training data and using unsupervised learning to construct the model. The robustness of the proposed system is evaluated using the performance evaluation metrics sum of squared error (SSE) and time to …


Analyzing Different Sampling Designs (Sas), Ying Lu May 2016

Analyzing Different Sampling Designs (Sas), Ying Lu

Journal of Modern Applied Statistical Methods

Various sampling designs are reviewed within the framework of probability sampling. SAS® code to estimate means and proportions, and their standard errors, using different sampling designs are illustrated using example data sets.


Bayesian Estimation Of P[Y < X] Based On Record Values From The Lomax Distribution And Mcmc Technique, Mohamed A. W Mahmoud, Rashad M. El-Sagheer, Ahmed A. Soliman, Ahmed H. Abd Ellah May 2016

Bayesian Estimation Of P[Y < X] Based On Record Values From The Lomax Distribution And Mcmc Technique, Mohamed A. W Mahmoud, Rashad M. El-Sagheer, Ahmed A. Soliman, Ahmed H. Abd Ellah

Journal of Modern Applied Statistical Methods

Our interest is in estimating the stress-strength reliability R = P[Y < X], where X and Y follow the Lomax distribution with common scale parameter. We discuss the problem in the situation where the stress measurements and the strength measurements are both in terms of records. Firstly, we obtain the MLE of R in general case (the common scale parameter is unknown). The MLE of the three unknown parameters can be obtained by solving one non-linear equation. We provide a simple fixed point type algorithm to find the MLE. We propose percentile bootstrap confidence intervals of R. A Bayes …


Graphing Effects As Fuzzy Numbers In Meta-Analysis, Christopher G. Thompson May 2016

Graphing Effects As Fuzzy Numbers In Meta-Analysis, Christopher G. Thompson

Journal of Modern Applied Statistical Methods

Prior to quantitative analyses, meta-analysts often explore descriptive characteristics of effect sizes. A graphic is proposed that treats effect sizes as fuzzy numbers. This plot can provide meta-analysts with such information such as heterogeneity of effects, precision of estimates, possible clusters, and existence of outliers.


Principal Component Preliminary Test Estimator In The Linear Regression Model, Sivarajah Arumairajan, Pushpakanthie Wijekoon May 2016

Principal Component Preliminary Test Estimator In The Linear Regression Model, Sivarajah Arumairajan, Pushpakanthie Wijekoon

Journal of Modern Applied Statistical Methods

A Preliminary Test Estimator is introduced based on Principal Component Regression Estimator defined in the linear regression model when the stochastic restrictions are available in addition to the sample information, and when the explanatory variables are multicollinear. It is further developed as a large sample preliminary test estimator by using Wald (WA), Likelihood Ratio (LR), and Lagrangian Multiplier (LM) tests. Stochastic properties of this estimator based on F test as well as WA, LR, and LM tests are derived, and the performance of the estimator is compared using WA, LR, and LM tests with respect to Mean Square Error Matrix …


New Procedures Of Estimating Proportion And Sensitivity Using Randomized Response In A Dichotomous Finite Population, Tanveer A. Tarray, Housila P. Singh May 2016

New Procedures Of Estimating Proportion And Sensitivity Using Randomized Response In A Dichotomous Finite Population, Tanveer A. Tarray, Housila P. Singh

Journal of Modern Applied Statistical Methods

The problem of estimating the population proportion possessing a sensitive attribute using simple random sampling with replacement (SRSWR) is advocated. Two new procedures are proposed. The suggested models are more efficient than the Huang (2004) randomized response technique under some realistic conditions. Numerical and graphic illustrations are given.


Construction Of Pair-Wise Balanced Design, Rajarathinam Arunachalam, Mahalakshmi Sivasubramanian, Dilip Kumar Ghosh May 2016

Construction Of Pair-Wise Balanced Design, Rajarathinam Arunachalam, Mahalakshmi Sivasubramanian, Dilip Kumar Ghosh

Journal of Modern Applied Statistical Methods

A new procedure for construction of pair wise balanced design with equal replication and un-equal block sizes based on factorial design have been evolved. Numerical illustration also provided. It was found that the constructed pair wise balanced design was found to be universal optimal.


Mathematics And Origami; Unfolding Mathematical "Impossibilities", Dustin Tyler Adams May 2016

Mathematics And Origami; Unfolding Mathematical "Impossibilities", Dustin Tyler Adams

Celebration of Student Scholarship Poster Sessions Archive

No abstract provided.


Extending The Supermassive Black Hole Mass-Pitch Angle Relation To Moderate Redshifts, Logan H. Jones May 2016

Extending The Supermassive Black Hole Mass-Pitch Angle Relation To Moderate Redshifts, Logan H. Jones

Physics Undergraduate Honors Theses

I extend the empirical correlation between central supermassive black hole mass M and spiral arm pitch angle P in spiral galaxies to intermediate redshifts using a sample of 14 type 1 Seyfert galaxies. Nuclear black hole masses are measured from the widths and luminosities of the broad Hβ and MgII emission lines, and pitch angles are measured using two independent image analysis techniques. I find the best-fit relation log(M/M☉) = (8.31 ± 0.28) − (0.058 ± 0.016)P, which indicates little to no evolution compared to the published M-P relation for local spirals.


Biological Aggregation Driven By Social And Environmental Factors: A Nonlocal Model And It Degenerate Cahn-Hilliard Approximation, Andrew J. Bernoff, Chad Topaz May 2016

Biological Aggregation Driven By Social And Environmental Factors: A Nonlocal Model And It Degenerate Cahn-Hilliard Approximation, Andrew J. Bernoff, Chad Topaz

Faculty Publications

No abstract provided.


Changes In Floristic Composition In The State Forests In Worcester County (Massachusetts) Over 34 Years, Flor A. Monroe May 2016

Changes In Floristic Composition In The State Forests In Worcester County (Massachusetts) Over 34 Years, Flor A. Monroe

Sustainability and Social Justice

ABSTRACT

CHANGES IN FOREST DIVERSITY OF STATE FOREST IN WORCESTER COUNTY, MASSACHUSETTS, OVER 34 YEARS PERIOD

The forest in Massachusetts has changed since the earliest colonial settlement and today the floristic composition is more homogeneous. This study investigates the potential change in the floristic composition over thirty years in Worcester County State Forests. Shannon, richness and evenness indices for two periods were compared, and Jaccard index was used to analyze similarity in composition between the periods. The possible influence of severe weather events was also analyzed.

It was found Changes in the floristic composition, but the magnitude of the changes …


Environmental Science And Policy Master’S Portfolio, Nathaniel K. Lapides May 2016

Environmental Science And Policy Master’S Portfolio, Nathaniel K. Lapides

Sustainability and Social Justice

The following Environmental Science and Policy Master’s Portfolio is a compilation of works completed individually and with peers in order to fulfill requirements for the Master of Science degree. These works demonstrate breadth, depth, and the interdisciplinary nature of the course of study. As an undergraduate student at Clark University I studied Environmental Science with a concentration in Earth Systems Science. I was interested in learning about the natural world and wanted to develop a deeper connection to it. Inevitably, I was exposed to courses that examined the causes and effects of global climate change and this topic became my …


Development Of A Decision Support System For Post Mining Land Use On Abandoned Surface Coal Mines In Appalachia, Matthew Zimmerman May 2016

Development Of A Decision Support System For Post Mining Land Use On Abandoned Surface Coal Mines In Appalachia, Matthew Zimmerman

Sustainability and Social Justice

Decision support systems are diverse and have been used to solve multiple problems ranging from the complex to the simple. With the complexity of environmental decisions today, these systems provide a logic based approach to evaluating and choosing environmental solutions. Abandoned mining lands (AML) are an issue for the environment in the Appalachian region. Given this a decision support system was designed using previously created frameworks and indices from other systems created. The system is comprised of two main sections, selecting the ideal post-mining land-use (PMLU), and maximizing the potential of land to be reclaimed under budgetary constraints. This system …