Physical Sciences and Mathematics Commons^™

Evaluate The Use Of Fpga Soc For Real Time Data Acquisition And Aggregate Micro-Texture Measurement Using Laser Sensors, Mudit Pradhan

Computer Science and Engineering Theses - Archive

Aggregate texture has been found to play an important role in improving the longevity of highways and pavements. Aggregates with appropriate surface roughness level have an improved bonding with asphalt binder and concrete mixture to produce a more durable road surface. Macro-texture has been found to effect certain other important features of the road surface for example, the skid resistance, flow of water on the surface and noise of the tyre on road. However, more research need to done to access the impact of surface texture at micro-meter level. Accurate measurement of the micro-texture at high resolution and in real-time …

Lilac: The Second Generation Lightweight Low-Latency Anonymous Chat., Revanth Rao Pobala

Computer Science and Engineering Theses - Archive

Instant messaging is one of the most used modes of communication and there are many instant messaging systems available online. Studies from the Electronic Frontier Foundation show that there are only a few instant messengers that keep your messages safe by providing ,security and limited anonymity. Lilac, a Lightweight Low-latency Anonymous Chat, is a secure instant messenger that provides security as well as better anonymity to users as compared to other messengers. It is a browser-based instant messaging system that uses Tor like a model to protect user anonymity. Compared to existing messengers, LILAC protects the users from tra?c analysis …

Reproductive Numbers For Periodic Epidemic Systems, Christopher David Mitchell

Mathematics Dissertations - Archive

When using mathematics to study epidemics, often times the goal is to deter- mine when an infection can invade and persist within a population. This can be done in a variety of ways but the most common is to use threshold quantities called reproductive numbers. For models with only one infection, the basic reproductive number (BRN) is used to determine the stability of the disease-free equilibrium. For many years this was done solely for autonomous systems; however, many diseases exhibit seasonal behavior. If this seasonality is incorporated into models, it gives nonautonomous systems, which while more accurate in their description, …

The Monadnock Volume 58, August 2016, Clark University Geographical Society

The Monadnock (Clark Geographical Society)

Volume 58 of The Monadnock. The Monadnock was the alumni magazine of the Clark University Geographical Society (1927-1985) (2014-present).

An R-Matrix, Quantum Defect Theory Approach To The Photoionization Of Molecular Nitrogen, Gaetan L. Vangyseghem

Dissertations

No abstract provided.

Improving Accuracy In Large Vocabulary Sign Search Systems, Christopher Conly

Computer Science and Engineering Dissertations - Archive

An automated computer vision-based dictionary system for looking up the meaning of signs can be an invaluable tool both for students and native users of sign languages. Students may not know the meaning of a sign they encounter and would like to learn what it is. A native signer knows what it means to them but may be unsure of the equivalent in English. Such a system can return a ranked video list of the most similar signs to a query video and allow the user to browse the video results to find the desired sign and its meaning. This …

Right-Hand Polarized 4FCe Auroral Roar Emissions: 2. Nonlinear Generation Theory, P. H. Yoon, J. Labelle, Allan T. Weatherwax

Physics Faculty Publications

Auroral roar emissions are commonly interpreted as Z (or upper hybrid) mode naturally excited by precipitating auroral electrons. Subsequent conversion to escaping radiation makes it possible for these emissions to be detected on the ground. Most emissions are detected as having left-hand (L) circular (or ordinary O) polarization, but the companion paper presents a systematic experimental study on the rare occurrence of the right-hand polarized, or equivalently, extraordinary (X) mode 4f_ce emission. A similar observation was reported earlier by Sato et al. (2015). The suggested emission mechanism is the nonlinear coalescence of …

Design And Evaluation Of Hmp Kinase Analogs As Thiamine Pathway Inhibitors, Diego A. Lopez

Chemistry & Biochemistry Dissertations - Archive

Current bacterial chemotherapy faces an overwhelming reduction in efficacy due to an increase in bacterial resistance; resulting in a higher clinical demand for novel therapeutics and the investigation for their respective targets. Vitamin pathways exogenous to the human body represent an attractive target for drug development since the enzymatic machinery is solely and ubiquitously to many infectious agents. HMP kinase [E.C 2.7.1.49] is a key enzyme in the thiamine metabolism. It catalyzes two subsequent phosphorylations of 4-amino-5-hydroxymethyl-2-methylpyrimidine (HMP), making it indispensable for microbial survival. Our efforts aimed for a substrate-based approach, where over 50 HMP analogs were synthesized and assayed …

Derivatization Of Small Acids To Enhance Sensitivity In Gas Chromatography Mass Spectrometry And Gas Chromatography Vacuum Ultraviolet Spectroscopy, Chih-Hao Wang

Chemistry & Biochemistry Theses - Archive

Disinfection by-products (DBPs) are a significant concern in drinking water quality. Haloacetic acids, which are generated from disinfection processes, are one of the major groups in disinfection by-products. Because they induce potential harmful effects for human health, the US government has already established regulations to control the levels of haloacetic acids in drinking water. In order to control the presence of haloacetic acids in drinking water and monitor other potential harmful compounds, an appropriate analytical method is needed. In this study, a gas chromatography (GC) method was developed for detecting haloacetic acids in water. Three different derivatization reagents were compared …

Method Development For Qualification And Quantification Of Cannabinoids And Terpenes In Extracts By Gas Chromatography-Mass Spectrometry, Allegra Leghissa

Chemistry & Biochemistry Theses - Archive

Cannabinoids are a class of chemical compounds that act on cannabinoid receptors in cells. These receptors have different kinds of ligands, including endocannabinoids (produced in the body by humans and animals), phytocannabinoids (found mainly in Cannabis sativa), and synthetic cannabinoids. At least 85 different phytocannabinoids have been isolated; different cannabinoids are believed to have different effects and possible benefits in medical treatments, and it is therefore fundamental to classify cultivars prior to their medical use. The other class of compounds that characterize C.sativa are terpenes. They confer flavor and fragrance that are unique to each plant and further confer botanical …

Distributed Data Management In Opportunistic Networks, Chance Ray Eary

Computer Science and Engineering Dissertations - Archive

Opportunistic networks (ONs) allow wireless devices, primarily mobile, to interact with one another through a series of opportunistic contacts. While ONs exploit mobility of devices to route messages and distribute information in the absence of dedicated networking infrastructure, the intermittent connections among devices make many traditional computer collaboration paradigms difficult to realize. Two such paradigms are distributed transactions and distributed shared memory (DSM). Distributed transactions are a sequence of operations, executed across multiple nodes, that must successfully complete as specified by its program, or abort with no changes to memory. DSM allows multiple, independent nodes to collectively operate on a …

Numerical Construction Of Diffeomorphism And The Applications To Grid Generation And Image Registration, Xi Chen

Mathematics Dissertations - Archive

Diffeomorphism is an active research topic in differential geometry. In this area, the existence and construction of diffeomorphism under certain constraints is an interesting and meaningful task. J. Moser first proved the existence of diffeomorphism under a Jacobian determinant constraint. Later, Dr. Liao along with his co-authors, proposed the deformation method to construct diffeomorphisms. A div-curl system is created in the construction of diffeomorphisms. Since the Jacobian determinant has a direct physical meaning in grid generation, i.e. the grid cell size, the deformation method was applied successfully to grid generation and adaptation problems. In this dissertation, we review the deformation …

Changes In R, R Core Team

The R Journal

CHANGES IN R 3.3.1 patched

CHANGES IN R 3.3.1

CHANGES IN R 3.3.0

Changes On Cran, Kurt Hornik, Achim Zeileis

The R Journal

In the past 8 months,1322 new packages were added to the CRAN package repository. 43 packages were unarchived,48 archived,1 package had to be removed.The following shows the growth of the number of active packages in the CRAN package repository:

Nonparametric Tests For The Interaction In Two-Way Factorial Designs Using R, Jos Feys

The R Journal

An increasing number of R packages include nonparametric tests for the interaction in two-way factorial designs. This paper briefly describes the different methods of testing and reports the resulting p-values of such tests on datasets for four types of designs: between, within, mixed, and pretest-posttest designs. Potential users are advised only to apply tests they are quite familiar with and not be guided by p-values for selecting packages and tests.

Spatio-Temporal Interpolation Using Gstat, Benedikt Gräler, Edzer Pebesma, Gerard Heuvelink

The R Journal

We present new spatio-temporal geostatistical modelling and interpolation capabilities of the R package gstat. Various spatio-temporal covariance models have been implemented, such as the separable, product-sum, metric and sum-metric models. Inareal-world application we comparespatio temporal interpolations using these models with a purely spatial kriging approach. The target variable of the application is the daily mean PM10 concentration measured at rural air quality monitoring stations across Germany in 2005. R code for variogram fitting and interpolation is presented in this paper to illustrate the workflow of spatio-temporal interpolation using gstat. We conclude that the system works properly and that the …

Model Builder For Item Factor Analysis With Openmx, Joshua N. Pritikin, Karen M. Schmidt

The R Journal

We introduce a shiny web application to facilitate the construction of Item Factor Analysis (a.k.a. Item Response Theory) models using the OpenMx package. The web application assists with importing data, outcome recoding, and model specification. However, the app does not conduct any analysis but, rather, generates an analysis script. Generated Rmarkdown output serves dual purposes: to analyze a data set and demonstrate good programming practices. The app can be used as a teaching tool or as a starting point for custom analysis scripts.

Maps, Coordinate Reference Systems And Visualising Geographic Data With Mapmisc, Patrick E. Brown

The R Journal

The mapmisc package provides functions for visualising geospatial data, including fetching background map layers, producing colour scales and legends, and adding scale bars and orientation arrows to plots. Background maps are returned in the coordinate reference system of the dataset supplied, and inset maps and direction arrows reflect the map projection being plotted. This is a “light weight” package having an emphasis on simplicity and ease of use

Metaplus: An R Package For The Analysis Of Robust Meta-Analysis And Meta-Regression, Ken J. Beath

The R Journal

The metaplus package is described with examples of its use for fitting meta-analysis and meta-regression. For either meta-analysis or meta-regression it is possible to fit one of three models: standard normal random effect, t-distribution random effect or mixture of normal random effects. The latter two models allow for robustness by allowing for a random effect distribution with heavier tails than the normal distribution, and for both robust models the presence of outliers may be tested using the parametric bootstrap. For the mixture of normal random effects model the outlier studies may be identified through their posterior probability of membership in …

Conditional Fractional Gaussian Fields With The Package Fieldsim, Alexandre Brouste, Jacques Istas, Sophie Lambert-Lacroix

The R Journal

We propose an effective and fast method to simulate multidimensional conditional fractional Gaussian fields with the package FieldSim. Our method is valid not only for conditional simulations associated to fractional Brownian fields, but to any Gaussian field and on any (non regular) grid of points.

Statmod: Probability Calculations For The Inverse Gaussian Distribution, Göknur Giner, Gordon K. Smyth

The R Journal

The inverse Gaussian distribution (IGD) is a well known and often used probability distribution for which fully reliable numerical algorithms have not been available. We develop fast, reliable basic probability functions (dinvgauss, pinvgauss, qinvgauss and rinvgauss) for the IGD that work for all possible parameter values and which achieve close to full machine accuracy. The most challenging task is to compute quantiles for given cumulative probabilities and we develop a simple but elegant mathematical solution to this problem. We show that Newton’s method for finding the quantiles of a IGD always converges monotonically when started from the mode of the …

Heteroscedastic Censored And Truncated Regression With Crch, Jakob W. Messner, Georg J. Mayr, Achim Zeileis

The R Journal

The crch package provides functions for maximum likelihood estimation of censored or truncated regression models with conditional heteroscedasticity along with suitable standard methods to summarize the fitted models and compute predictions, residuals, etc. The supported distributions include left- or right-censored or truncated Gaussian, logistic, or student-t distributions with potentially different sets of regressors for modeling the conditional location and scale. The models and their R implementation are introduced and illustrated by numerical weather prediction tasks using precipitation data for Innsbruck (Austria).

Stylometry With R: A Package For Computational Text Analysis, Maciej Eder, Jan Rybicki, Mike Kestemont

The R Journal

This software paper describes ‘Stylometry with R’ (stylo), a flexible R package for the high level analysis of writing style in stylometry. Stylometry (computational stylistics) is concerned with the quantitative study of writing style, e.g. authorship verification, an application which has considerable potential in forensic contexts, as well as historical research. In this paper we introduce the possibilities of stylo for computational text analysis, via a number of dummy case studies from English and French literature. We demonstrate how the package is particularly useful in the exploratory statistical analysis of texts, e.g. with respect to authorial writing style. …

Sbtools: A Package Connecting R To Cloud-Based Data For Collaborative Online Research, Luke A. Winslow, Scott Chamberlain, Alison P. Appling, Jordan S. Read

The R Journal

The adoption of high-quality tools for collaboration and reproducibile research such as R and Github is becoming more common in many research fields. While Github and other version management systems are excellent resources, they were originally designed to handle code and scale poorly to large text-based or binary datasets. A number of scientific data repositories are coming online and are often focused on dataset archival and publication. To handle collaborative workflows using large scientific datasets, there is increasing need to connect cloud-based online data storage to R. In this article, we describe how the new R package sbtools enables direct …

Mclust 5: Clustering, Classification And Density Estimation Using Gaussian Finite Mixture Models, Luca Scrucca, Michael Fop, T Brendan Murphy, Adrian E. Raftery

The R Journal

Finite mixture models are being used increasingly to model a wide variety of random phenomena for clustering, classification and density estimation. mclust is a powerful and popular package which allows modelling of data as a Gaussian finite mixture with different covariance structures and different numbers of mixture components, for a variety of purposes of analysis. Recently, version 5 of the package has been made available on CRAN.This updated version adds new covariance structures, dimension reduction capabilities for visualisation, model selection criteria, initialisation strategies for the EM algorithm, and bootstrap-based inference, making it a full-featured R package for data analysis via …

Gender Prediction Methods Based On First Names With Genderizer, Kamil Wais

The R Journal

In recent years, there has been increased interest in methods for gender prediction based on f irst names that employ various open data sources. These methods have applications from bibliometric studies to customizing commercial offers for web users. Analysis of gender disparities in science based on such methods are published in the most prestigious journals, although they could be improved by choosing the most suited prediction method with optimal parameters and performing validation studies using the best data source for a given purpose. There is also a need to monitor and report how well a given prediction method works in …

Clustering.Sc.Dp: Optimal Clustering With Sequential Constraint By Using Dynamic Programming, Tibor Szkaliczki

The R Journal

The general clustering algorithms do not guarantee optimality because of the hardness of the problem. Polynomial-time methods can find the clustering corresponding to the exact optimum only in special cases. For example, the dynamic programming algorithm can solve the one-dimensional clustering problem, i.e., when the items to be clustered can be characterised by only one scalar number. Optimal one-dimensional clustering is provided by package Ckmeans.1d.dp in R. The paper shows a possible generalisation of the method implemented in this package to multidimensional data: the dynamic programming method can be applied to find the optimum clustering of vectors when only subsequent …

News From The Bioconductor Project, Bioconductor Team

The R Journal

The Bioconductor project provides tools for the analysis and comprehension of high throughput genomic data. The 1211 software packages available in Bioconductor can be viewed at http://bioconductor.org/packages/. Navigate packages using ‘biocViews’ terms and title search. Each package has an html page with a description, links to vignettes, reference manuals, and usage statistics. Start using Bioconductor version 3.3 by installing R 3.3.1 and evaluating the commands

An Interactive Survey Application For Validating Social Network Analysis Techniques, Mitchell Joblin, Wolfgang Mauerer

The R Journal

Social network analysis is extremely well supported by the R community and is routinely used for studying the relationships between people engaged in collaborative activities. While there has been rapid development of new approaches and metrics in this field, the challenging question of validity (how well insights derived from social networks agree with reality) is often difficult to address. We propose the use of several R packages to generate interactive surveys that are specifically well suited for validating social network analyses. Using our web-based survey application, we were able to validate the results of applying community-detection algorithms to infer the …

Conference Report: User! 2016, Joe Rickert

The R Journal

The 12th international R user conference, useR! 2016, took place at Stanford University, Stanford CA fromJune27throughJune30th. Hosted by the Stanford University Department of Statistics and the Stanford Libraries, the conference took place at the Frances Arrillaga Alumni Center, on the surrounding lawns and in several adjacent buildings. The floor to ceiling windows of the larger conference rooms, the garden locations for coffee and meals and the beautiful weather contributed to making the event a classic California experience.