Digital Commons Network^™

A Context-Free Method Of Visualizing Streaming Object Data For The Purpose Of Identifying Known Events: An Implementation And Analysis, Quinn Gregory Carver

Theses and Dissertations

This year, every second, five gigabytes of new data will be streamed to storage and yet less than half a percent of all this data will ever be analyzed. Much of this muted data is high-variety object data, unnoticed in a void of sorely needed tools to make it readily understandable. A software tool for visualizing streaming object data in a context-free manner can be built, and this tool would aid in finding predictor data for known events which are functions of the data. The design of the tool to support the hypothesis is presented and field results from over …

Performance Evaluation Of Mission Critical Communications Services Over Lte Networks, Kehinde Olumide Olasupo

Theses and Dissertations

he existing Private/Professional Mobile Radio (PMR) technologies designed specifically for Mission Critical Communication (MCC) systems are narrowband and wideband devices, with limited network data capacity in emergency scenarios. They are majorly used to support MCC voice communications and low data rate applications during mission critical operations. However, the need for broadband systems that would support high radio data capacity keep increasing during major incidents and accident scenarios. Because of this, the MCC agencies were attracted by the broadband capabilities of Long Term Evolution (LTE) technology. But, the uplink capacity of LTE- based MCC systems is still a concern. In planning …

Model Based Systems Engineering High Level Design Of A Sustainable Electric Vehicle Charging And Swapping Station Using Discrete Event Simulation, Obinna Henry Ginigeme

Theses and Dissertations

In line with the spate of technological advances, the transportation industry has also witnessed an increase in the adoption of Electric Vehicles (E.Vs). However, there has been and are still some underlying negating factors to the wide spread acceptance of these electric vehicles; one of note is the unavailability and inaccessibility of adequate charging infrastructure, long charging times, limited driving ranges, costs of the vehicles etc. These and many more characteristics lead to a trend popularly known as “range anxiety”. One of the major strengths of electric vehicles are their ability to be powered by electric energy via stored chemical …

Mining Location And User Information From Users’ Trajectories, Marcello Tomasini

Theses and Dissertations

The understanding of human mobility is integral to the advancement of many fields including public health, city planning, economic forecasting, and it attracts the interest of researchers from a broad number of fields. The work of such researchers would not have been possible without the availability of large localized datasets such as mobile phone Call Detail Records (CDRs) provided by telco operators and Location Based Social Networks (LBSNs) check-ins provided by popular applications such as Twitter, Facebook and Foursquare. However, such datasets are often incomplete, anonymized, and/or inaccurate. Hence there is a need to partially reconstruct or extract more information …

Efficiency Analysis And Optimization Of Light Trapping In Amorphous Silicon Heterojunction Solar Cell With Lumerical Fdtd/Device, Muhammad Riaz

Theses and Dissertations

This study investigated the two-dimensional computer analysis of a tandem solar cell: c-Si/a-Si:H/µc-SiGe, with Lumerical FDTD/DEVICE 4.6. Optical characterization was performed in FDTD and then the total generation rate was transported into DEVICE for electrical characterization. Electrical characterization of the solar cell was carried out in DEVICE. In the first stage, a single junction solar cell was studied with both a-Si and µc-SiGe, respectively, as its absorbing layers. The thickness for both layers was kept the same. For the a-Si absorbing layer Jsc = 10.959 mA/cm2 , Voc = 696.97 mV, FF = 78.985%, and η = 6.033% were achieved. …

Parametric And Non-Parametric Regression Models With Applications To Climate Change, Osita Eluemuno Onyejekwe

Theses and Dissertations

In this dissertation we have studied the climate factors that contribute to climate change using univariate and multivariate parametric methods as well as nonparametric models. In this study, we have three major contributions. First, the extent of mountain glaciers around the globe and their responses to climate factors are investigated using multivariate methods and we have proposed a predictive model to estimate the mountain glacier response to climate factors. Second, we have addressed the important problem of bandwidth selection in presence of correlated noise in nonparametric regression analysis. We have proposed a denoising method based on an ensemble bandwidth optimization …

Effects Of Spatial Ability And Three-Dimensional Interactive Computer-Assisted Instruction On Functional Anatomy Learning, Kelly Michael Moore

Theses and Dissertations

The purpose of this study was to determine the effects of spatial ability (SA) and three-dimensional (3D) interactive Computer-assisted instruction (CAI) on college student academic achievement (ACH). The study was a quasi-experimental, pretest-posttest, control group mixed methods design. Participants were assessed for spatial ability via the Revised Purdue Spatial Visualization Test: Visualization of Rotations (Revised PSVT:R), Yoon (2011). Participants were instructed to identify, locate and visualize human skeletal muscles and muscle actions. During laboratory sessions, control groups studied plastic anatomical 3D models and experiment groups utilized 3D interactive CAI. ACH was measured by the Human Skeletal Muscle Assessment (HSMA) difference …

A Comparative Study Of Discovery Learning Scientific Community Laboratories And Traditional Laboratories In Physics At An Independent University, Florida, U. S., Muhammad Riaz

Theses and Dissertations

This study investigated the effects of two instructional approaches – Discovery Learning Scientific Community Laboratories (DL-SCL; Treatment) and non-DLSCL laboratories (Control) – on students’ conceptual understanding, epistemological views, and academic achievement in a Physics-1 lab. Conceptual understanding was measured pre/post using the Mechanics Baseline Test (MBT) and the Force Concept Inventory (FCI). Epistemological views were measured pre/post using the E-CLASS (Zwickl et al., 2014). Lab scores and final exam scores served as measures of academic achievement. This study used a quasi-experimental study design with mixed-methods data collection and analysis procedures. Sections of a Physics-1 Lab course in Fall 2016 were …

On Logconcavity Of Multivariate Discrete Distributions, Majed Ghazi Alharbi

Theses and Dissertations

The contribution of this dissertation to the literature is twofold. First, we use a geometric perspective to present all possible subdivisions of R³ into tetrahedra with disjoint interiors and adopt a combinatorial approach to obtain a special subdivision of Rⁿ into simplices with disjoint interiors, where two simplices are called neighbors if they share a common facet. We then use the neighborhood relationship of the simplices in each subdivision to fully describe the sufficient conditions for the strong unimodality/logconcavity of the trivariate discrete distributions and further extend these results to present a new sufcient condition for the strong unimodality/logconcavity of …

The Effects Of Teaching Middle School Students Math Using The Gifted Supplementary Curriculum “Mawhiba” On Students’ Academic Achievement And Attitude Toward Math In Public Schools In Saudi Arabia, Ahmed M. Alreshidi

Theses and Dissertations

The purpose of this study was to investigate whether the use of a supplementary math curriculum, “Mawhiba,” that was designed for gifted students, would be appropriate for regular students in a mixed-abilities classroom. The researcher investigated the effects of implementing the Mawhiba enriched supplementary math curriculum on students’ achievements in mathematics and on students’ attitudes toward mathematics in Hail State, Saudi Arabia. The research design was an experimental randomized subject pretest, post-test, control group design. Two schools were chosen (a female middle school and a male middle school). The sample consisted of 121 students (60 males and 61 females). The …

Copper Tolerance Of Amphibalanus Amphitrite As Observed In Central Florida, Hannah Grace Brinson

Theses and Dissertations

Copper tolerance in the invasive barnacle Amphibalanus amphitrite has been observed in Florida by the Center for Corrosion and Biofouling Control since 2012 and by Weiss (1947). To test the theory that this barnacle preferentially settles on copper coated surfaces to avoid settlement competition by other sessile species, a series of two experiments and a literature review of historical copper toxicity tests on larval barnacles was conducted. The barnacle A amphitrite was preferentially used in many previous toxicity studies because it is readily available, has high fecundity, and is more sensitive to some toxicants than other species, including the native …

St. Lucie Shoal Complex: Regional Sediment Resource Or Submerged Storm Breakwater, Leaf Erickson

Theses and Dissertations

Nearshore sand shoals have become the predominant sediment resource for beach nourishment projects on the east coast of Florida. Along this coast, the St. Lucie Shoal Complex (SLSC) is comprised of several shoals designated as sediment resources for beach nourishment, many having depths less than 7 meters, at their crests. This group of shoals represents the largest high-quality beach nourishment sediment resource in southeast Florida. Among these shoals, the St. Lucie shoal is the largest and shallowest at the crest. This project explores the current best practice methodologies to explore impacts of excavating sand resources from shallow-crested shoal systems like …

Angle-Resolved Observation Of X-Ray Second Harmonic Generation In Diamond, Björn Senfftleben

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

This thesis reports angularly-resolved observation of X-ray second harmonic generation (XSHG) in diamond at several phase-matching geometries. The XSHG signal was produced by ultra-short, highly intense X-ray pulses with a photon energy of 9.831 keV generated by a free-electron laser. In some geometries for high pulse energies more than 10 second harmonic photons per pulse were generated.

Different phase-matched geometries were used for XSHG to investigate the angular dependence of the efficiency of the process. Furthermore, for each phase-matching condition, the quadratic dependence for second harmonic generation at each geometry was verified and the crystal rocking curves were measured. The …

Design And Construction Of A High-Current Femtosecond Gas-Phase Electron Diffraction Setup, Omid Zandi

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

We designed and constructed a state-of-the-art high current ultrafast gas electron diffraction experimental setup, which resolved two main challenges that constraint temporal resolution in previous setups. These aforementioned bottlenecks were: the space charge effect due to the Coulomb expansion, and the velocity mismatch between the sub-relativistic electrons (probe) and the exciting laser pulse (pump). In our setup, the problem of space charge effect was ameliorated by compressing 90 keV photo-emitted electron pulses using a radio-frequency electric field. The compression allowed us to increase the beam current by almost two orders of magnitude higher than previously reported. We developed a laser-activated …

A Measurement Of The Wy Cross Section At √S = 8 Tev In Pp Collisions With The Cms Detector, Ekaterina Avdeeva

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

A measurement of cross section of the Wγ → lνγ production in proton-proton collisions using 19.6 fb − 1 of LHC data collected by CMS detector at the center- √ of-mass collision energy of s = 8 TeV is reported. The W bosons are identified in their electron and muon decay modes. The process of Wγ production in the Standard Model (SM) involves a pure gauge boson coupling, a WWγ vertex, which allows one to test the electroweak sector of the SM in a unique way not achievable by studies of other processes. In addition to the total cross section, …

News From The Bioconductor Project, Bioconductor Core Team

The R Journal

The Bioconductor project provides tools for the analysis and comprehension of high throughput genomic data. Bioconductor 3.6 was released on 31 October, 2017. It is compatible with R 3.4.3 and consists of 1473 software packages, 326 experiment data packages, and 911 up-to-date annotation packages. The release announcement includes descriptions of 100 new software packages, and updated NEWS files for many additional packages. Start using Bioconductor by installing the most recent version of R and evaluating the commands

Changes On Cran, Kurt Hornik, Uwe Ligges, Achim Zeileis

The R Journal

In the past 6 months,1244 new packages were added to the CRAN package repository. 19 packages were unarchived, 55 archived and 3 removed. The following shows the growth of the number of active packages in the CRAN package repository

Splitting It Up: The Spduration Split-Population Duration Regression Package For Time-Varying Covariates, Andreas Beger, Daniel W. Hill Jr, Nils W. Metternich, Shahryar Minhas, Michael D. Ward

The R Journal

We present an implementation of split-population duration regression in the spduration (Beger et al., 2017) package for R that allows for time-varying covariates. The statistical model accounts for units that are immune to a certain outcome and are not part of the duration process the researcher is primarily interested in. We provide insights for when immune units exist, that can significantly increase the predictive performance compared to standard duration models. The package includes estimation and several post-estimation methods for split-population Weibull and log-logistic models. Weprovide an empirical application to data on military coups.

Partial Rank Data With The Hyper2 Package: Likelihood Functions For Generalized Bradley-Terry Models, Robin K. S Hankin

The R Journal

Here I present the hyper2 package for generalized Bradley-Terry models and give examples from two competitive situations: single scull rowing, and the competitive cooking game show Master Chef Australia. A number of natural statistical hypotheses may be tested straightforwardly using the software.

Riskregression: Predicting The Risk Of An Event Using Cox Regression Models, Brice Ozenne, Anne Lyngholm Sørensen, Thomas Scheike, Christian Torp-Pedersen, Thomas Alexander Gerds

The R Journal

In the presence of competing risks a prediction of the time-dynamic absolute risk of an event can be based on cause-specific Cox regression models for the event and the competing risks (Benichou and Gail, 1990). We present computationally fast and memory optimized C++functions with an R inter face for predicting the covariate specific absolute risks, their confidence intervals, and their confidence bands based on right censored time to event data. We provide explicit formulas for our implementation of the estimator of the (stratified) baseline hazard function in the presence of tied event times. As a by-product we obtain fast access …

Anomalydetection: Implementation Of Augmented Network Log Anomaly Detection Procedures, Robert J. Gutierrez, Bradley C. Boehmke, Air Force Institute Of Technology, Cade M. Saie, Trevor J. Bihl

The R Journal

As the number of cyber-attacks continues to grow on a daily basis, so does the delay in threat detection. For instance, in 2015, the Office of Personnel Management discovered that approximately 21.5 million individual records of Federal employees and contractors had been stolen. On average, the time between an attack and its discovery is more than 200 days. In the case of the OPM breach, the attack had been going on for almost a year. Currently, cyber analysts inspect numerous potential incidents on a daily basis, but have neither the time nor the resources available to perform such a task. …

Liureg: A Comprehensive R Package For The Liu Estimation Of Linear Regression Model With Collinear Regressors, Muhammad Imdadullah, Muhammad Aslam, Saima Altaf

The R Journal

The Liu regression estimator is now a commonly used alternative to the conventional ordinary least squares estimator that avoids the adverse effects in the situations when there exists a considerable degree of multicollinearity among the regressors. There are only a few software packages available for estimation of the Liu regression coefficients, though with limited methods to estimate the Liu biasing parameter without addressing testing procedures. Our liureg package can be used to estimate the Liu regression coefficients utilizing a range of different existing biasing parameters, to test these coefficients with more than 15 Liu related statistics, and to present different …

Ider: Intrinsic Dimension Estimation With R, Hideitsu Hino

The R Journal

In many data analyses, the dimensionality of the observed data is high while its intrinsic dimension remains quite low. Estimating the intrinsic dimension of an observed dataset is an essential preliminary step for dimensionality reduction, manifold learning, and visualization. This paper introduces an R package, named ider, that implements eight intrinsic dimension estimation methods, including a recently proposed method based on a second-order expansion of a probability mass function and a generalized linear model. The usage of each function in the package is explained with datasets generated using a function that is also included in the package

Furniture For Quantitative Scientists, Tyson S. Barrett, Emily Brignone

The R Journal

A basic understanding of the distributions of study variables and the relationships among them is essential to inform statistical modeling. This understanding is achieved through the computation of summary statistics and exploratory data analysis. Unfortunately, this step tends to be under-emphasized in the research process, in part because of the often tedious nature of thorough exploratory data analysis. The table1() function in the furniture package streamlines much of the exploratory data analysis process, making the computation and communication of summary statistics simple and beautiful while offering significant time-savings to the researcher

Crtgeedr: An R Package For Doubly Robust Generalized Estimating Equations Estimations In Cluster Randomized Trials With Missing Data, Melanie Prague, Rui Wang, Victor De Gruttola

The R Journal

Semi-parametric approaches based on generalized estimating equations (GEE) are widely used to analyze correlated outcomes in longitudinal settings. In this paper, we present a package CRTgeeDR developed for cluster randomized trials with missing data (CRTs). For use of inverse probability weighting to adjust for missing data in cluster randomized trials, we show that other software lead to biased estimation for non-independence working correlation structure. CRTgeeDR solves this problem. We also extend the ability of existing packages to allow augmented Doubly Robust GEEestimation (DR). Simulation studies demonstrate the consistency of estimators implemented in CRTgeeDR compared to packages such as geepack and …

Queueing: A Package For Analysis Of Queueing Networks And Models In R, Pedro Cañadilla Jiménez, Yolanda Román Montoya

The R Journal

queueing is a package that solves and provides the main performance measures for both basic Markovian queueing models and single and multiclass product-form queueing networks. It can be used both in education and for professional purposes. It provides an intuitive, straightforward wayto build queueing models using S3 methods. The package solves Markovian models of the form M/M/c/K/M/FCFS, open and closed single class Jackson networks, open and closed multiclass networks and mixed networks. Markovian models are used when both the customer inter-arrival time and the server processing time are exponentially distributed. Queueing network solvers are useful for modelling situations in which …

Allele Imputation And Haplotype Determination From Databases Composed Of Nuclear Families, Nathan Medina-Rodríguez, Ángelo Santana

The R Journal

The alleHap package is designed for imputing genetic missing data and reconstruct non recombinant haplotypes from pedigree databases in a deterministic way. When genotypes of related individuals are available in a number of linked genetic markers, the program starts by identifying haplotypes compatible with the observed genotypes in those markers without missing values. If haplotypes are identified in parents or offspring, missing alleles can be imputed in subjects containing missing values. Several scenarios are analyzed: family completely genotyped, children partially genotyped and parents completely genotyped, children fully genotyped and parents containing entirely or partially missing genotypes, and founders and their …

Fourierin: An R Package To Compute Fourier Integrals, Guillermo Basulto-Elias, Alicia Carriquiry, Kris De Brabanter, Daniel J. Nordman

The R Journal

We present the R package fourierin (Basulto-Elias, 2017) for evaluating functions defined as Fourier-type integrals over a collection of argument values. The integrals are finitely supported with integrands involving continuous functions of one or two variables. As an important application, such Fourier integrals arise in so-called “inversion formulas”, where one seeks to evaluate a probability density at a series of points from a given characteristic function (or vice versa) through Fourier transforms. This paper intends to fill a gap in current R software, where tools for repeated evaluation of functions as Fourier integrals are not directly available. We implement two …

Anchoreddistr: A Package For The Bayesian Inversion Of Geostatistical Parameters With Multi-Type And Multi-Scale Data, Heather Savoy, Falk Heße, Yoram Rubin

The R Journal

The Method of Anchored Distributions (MAD) is a method for Bayesian inversion designed for inferring both local (e.g. point values) and global properties (e.g. mean and variogram parameters) of spatially heterogenous fields using multi-type and multi-scale data. Software implementations of MAD exist in C++ and C# to import data, execute an ensemble of forward model simulations, and perform basic post-processing of calculating likelihood and posterior distributions for a given application. This article describes the R package anchoredDistr that has been built to provide an R based environment for this method. In particular, anchoredDistr provides a range of post-processing capabilities for …

Editorial, Roger Bivand

The R Journal

In my editorial for the 2017–1 issue, I concentrated on tabulating the status of this journal with respect to its authors and reviewers (updated tables below). This time, I was prompted by an interesting blog posting by Jan Wijffels of BNOSAC, describing the use of the udpipe package to apply natural language processing (NLP) to the CRAN package database available from tools::CRAN_package_db() since the release of R 3.4. The interactive NLP searcher is a dashboard permitting exploration of annotated CRAN package title and description NLP data.