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2014

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Articles 331 - 360 of 9800

Full-Text Articles in Physical Sciences and Mathematics

Urban Seismology For Groundwater Characterization In A Developing Country: Challenges And Rewards, John H. Bradford, Kyle Lindsay, Steve Silliman, Nicaise Yalo, Moussa Boukari Dec 2014

Urban Seismology For Groundwater Characterization In A Developing Country: Challenges And Rewards, John H. Bradford, Kyle Lindsay, Steve Silliman, Nicaise Yalo, Moussa Boukari

Geosciences Faculty Publications and Presentations

The coastal city of Cotonou in the developing country of Bénin, West Africa, is a large population center that is facing a serious threat to the sustainability of its freshwater supply. The city relies on the Godomey aquifer for domestic water, but the aquifer is undergoing saltwater intrusion. This problem is likely to worsen without significant steps to improve management of the water supply. Aquifer continuity and saltwater flow paths are poorly understood, but that information is critical to ensure sustainable access to freshwater in this growing urban center. In January 2012, a two-year geophysical investigation was begun with the …


Effects Of Major Sudden Stratospheric Warmings Identified In Midlatitude Mesospheric Rayleigh-Scatter Lidar Temperatures, Leda Sox, Vincent B. Wickwar, Chad Fish, Josh Herron Dec 2014

Effects Of Major Sudden Stratospheric Warmings Identified In Midlatitude Mesospheric Rayleigh-Scatter Lidar Temperatures, Leda Sox, Vincent B. Wickwar, Chad Fish, Josh Herron

Physics Student Research

Mesospheric temperature anomalies associated with Sudden Stratospheric Warmings (SSWs) have been observed extensively in the polar regions. However, observations of these anomalies at midlatitudes are sparse. The very dense 11-year data set, collected between 1993–2004, with the Rayleigh-scatter lidar at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W) at the Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU), has been carefully examined for such anomalies. The temperatures derived from these data extend over the mesosphere, from 45 to 90 km. During this period extensive data were acquired during seven major SSW events. In this …


Supergravity Backgrounds For Deformations Of Adsn×Sn Supercoset String Models, Oleg Lunin, Radu Roiban, Arkady Tseytlin Dec 2014

Supergravity Backgrounds For Deformations Of Adsn×Sn Supercoset String Models, Oleg Lunin, Radu Roiban, Arkady Tseytlin

Physics Faculty Scholarship

We consider type IIB supergravity backgrounds corresponding to the deformed AdS_n x S^n supercoset string models of the type constructed in arXiv:1309.5850 which depend on one deformation parameter k. In AdS_2 x S^2 case we find that the deformed metric can be extended to a full supergravity solution with non-trivial dilaton, RR scalar and RR 5-form strength. The solution depends on a free parameter (called a) that should be chosen as a particular function of k to correspond to the deformed supercoset model. In AdS_3 x S^3 case the full solution supported by the dilaton, RR scalar and RR 3-form …


Reliability-Based Design And Acceptance Protocol For Driven Piles, Joseph Jabo Dec 2014

Reliability-Based Design And Acceptance Protocol For Driven Piles, Joseph Jabo

Graduate Theses and Dissertations

The current use of the Arkansas Standard Specifications for Highway Construction Manuals (2003, 2014) for driven pile foundations faces various limitations which result in designs of questionable reliability. These specifications are based on the Allowable Stress Design method (ASD), cover a wide range of uncertainties, do not take into account pile and soil types, and were developed for general use. To overcome these challenges it is deemed necessary to develop a new design and acceptance protocol for driven piles. This new protocol incorporates locally calibrated RLFD resistance factors for accounting for local design and construction experiences and practices, as well …


Modeling Scenarios Of Sea-Level Rise And Human Migration: Rita Village, The Republic Of The Marshall Islands, Donna Davis Dec 2014

Modeling Scenarios Of Sea-Level Rise And Human Migration: Rita Village, The Republic Of The Marshall Islands, Donna Davis

Graduate Theses and Dissertations

This study explores the relationship between sea-level rise and human migration from Rita Village in the Republic of the Marshall Islands (RMI). As one of only four low-lying atoll countries at the forefront of risks associated with climate change, examining the extent to which sea level will rise and displace residents in the Marshall Islands is of timely importance. The approach to this research is a scenario-based, case study and it examines loss of home, human displacement and subsequent migration in Rita Village as a result of varying levels of sea level rise. The scenario-based approach is based on the …


Development Of A Hydrologic Model For An Urban Headwater Stream: The Influence Of Pervious Surface Properties On Runoff Dynamics, Dawn A. Farver Dec 2014

Development Of A Hydrologic Model For An Urban Headwater Stream: The Influence Of Pervious Surface Properties On Runoff Dynamics, Dawn A. Farver

Graduate Theses and Dissertations

A hydrologic model was developed for the Mullins Creek (MC) catchment located on the University of Arkansas campus in Fayetteville, Arkansas. The MC catchment is a small, dynamic urban stream system with a range of land use/land cover (LULC), an extensive and well-developed stormwater drainage network, and extensive urbanization (over 90% developed, and almost 50% impervious surface area (ISA)). Selected datasets provided information on the stormwater drainage network, the physical attributes of the catchment and receiving waterway (i.e. drainage area, slope, etc.), infiltration potential of soil map units, LULC, and percent ISA. These datasets were analyzed to provide input parameters …


Structure, Aboveground Biomass, And Soil Characterization Of Avicennia Marina In Eastern Mangrove Lagoon National Park, Abu Dhabi, Tareefa Alsumaiti Dec 2014

Structure, Aboveground Biomass, And Soil Characterization Of Avicennia Marina In Eastern Mangrove Lagoon National Park, Abu Dhabi, Tareefa Alsumaiti

Graduate Theses and Dissertations

Mangrove forests are national treasures of the United Arab Emirates (UAE) and other arid countries with limited forested areas. Mangroves form a crucial part of the coastal ecosystem and provide numerous benefits to society, economy, and especially the environment. Mangrove trees, specifically Avicennia marina, are studied in their native habitat in order to characterize their population structure, aboveground biomass, and soil properties. This study focused on Eastern Mangrove Lagoon National Park in Abu Dhabi, which was the first mangrove protected area to be designated in UAE. In situ measurements were collected to estimate Avicennia marina status, mortality rate (%), …


Positive Solutions Of Boundary Value Dynamic Equations, Olusegun Michael Otunuga, Basant Karna, Bonita Lawrence Dec 2014

Positive Solutions Of Boundary Value Dynamic Equations, Olusegun Michael Otunuga, Basant Karna, Bonita Lawrence

Mathematics Faculty Research

In this paper, we deal with the existence of a positive solution for 2nd and 3rd order boundary value problem by first defining their respective Green’s function. The Green’s function is used to derive the Green’s function for the 2nth and 3nth order boundary value problem, respectively, where n is a positive integer. The Green’s function is also used to derive conditions for positive solution of the 2nth and 3nth order eigen value differential equation, respectively.


Identifying Change Points In A Covariate Effect On Time-To-Event Analysis With Reduced Isotonic Regression, Yong Ma, Yinglei Lai, John M. Lachin Dec 2014

Identifying Change Points In A Covariate Effect On Time-To-Event Analysis With Reduced Isotonic Regression, Yong Ma, Yinglei Lai, John M. Lachin

GW Biostatistics Center

Isotonic regression is a useful tool to investigate the relationship between a quantitative covariate and a time-to-event outcome. The resulting non-parametric model is a monotonic step function of a covariate X and the steps can be viewed as change points in the underlying hazard function. However, when there are too many steps, over-fitting can occur and further reduction is desirable. We propose a reduced isotonic regression approach to allow combination of small neighboring steps that are not statistically significantly different. In this approach, a second stage, the reduction stage, is integrated into the usual monotonic step building algorithm by comparing …


Hampton Roads Sea Level Rise Preparedness And Resilience Intergovernmental Planning Pilot Project, Ray Toll, David Architzel Dec 2014

Hampton Roads Sea Level Rise Preparedness And Resilience Intergovernmental Planning Pilot Project, Ray Toll, David Architzel

Presentations, Lectures, Posters, Reports

No abstract provided.


Book Review - Wild Connection: What Animal Courtship And Mating Tell Us About Human Relationships, J. Matthew Hoch Dec 2014

Book Review - Wild Connection: What Animal Courtship And Mating Tell Us About Human Relationships, J. Matthew Hoch

Marine & Environmental Sciences Faculty Articles

No abstract provided.


Scaling Group Analysis On Mhd Free Convective Heat And Mass Transfer Over A Stretching Surface With Suction / Injection, Heat Source/Sink Considering Viscous Dissipation And Chemical Reaction Effects, Hunegnaw Dessie, Naikoti Kishan Dec 2014

Scaling Group Analysis On Mhd Free Convective Heat And Mass Transfer Over A Stretching Surface With Suction / Injection, Heat Source/Sink Considering Viscous Dissipation And Chemical Reaction Effects, Hunegnaw Dessie, Naikoti Kishan

Applications and Applied Mathematics: An International Journal (AAM)

This paper concerns with scaling group analysis on MHD free convective heat and mass transfer over stretching surface considering effects of thermal-diffusion and diffusion-thermo with suction /injection, heat source/sink and chemical reaction by taking into account viscous dissipation. Scaling group transformations are used to convert the partial differential equations of governing equations into ordinary differential equation and are solved numerically by Keller Box Method. Numerical results obtained for different parameters are drawn graphically and their effects on velocity, temperature and concentration profiles are discussed and shown graphically. Skin-friction coefficient, Nusselt number and Sherwood number are presented in table. It is …


Steady Quadratic Stokes Flow Past Deformed Sphere: A Novel Perturbation Technique, Deepak K. Srivastava, Nirmal Srivastava, Raja R. Yadav Dec 2014

Steady Quadratic Stokes Flow Past Deformed Sphere: A Novel Perturbation Technique, Deepak K. Srivastava, Nirmal Srivastava, Raja R. Yadav

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, the problem of steady quadratic Stokes flow past a deformed sphere has been tackled with the use of a novel perturbation technique in both situations when a uniform stream is along the axis of symmetry (axial flow) and when it is perpendicular to the axis of symmetry (transverse flow). The most general form of the deformed sphere, governed by polar equation, is considered here for the study. The general expressions for axial and transverse Stokes drag for deformed sphere has been derived up to the second order of deformation parameter for parabolic and stagnation like parabolic flow. …


Core Handling And Processing For The Wais Divide Ice-Core Project, Joseph Souney Jr, Mark S. Twickler, Geoffrey M. Hargreaves, Brian M. Bencivengo, Matthew J. Kippenhan, Jay A. Johnson, Eric D. Cravens, Peter D. Neff, Richard M. Nunn, Anais J. Orsi, Trevor J. Popp, John F. Rhoades, Bruce H. Vaughn, Donald E. Voigt, Gifford J. Wong, Kendrick C. Taylor Dec 2014

Core Handling And Processing For The Wais Divide Ice-Core Project, Joseph Souney Jr, Mark S. Twickler, Geoffrey M. Hargreaves, Brian M. Bencivengo, Matthew J. Kippenhan, Jay A. Johnson, Eric D. Cravens, Peter D. Neff, Richard M. Nunn, Anais J. Orsi, Trevor J. Popp, John F. Rhoades, Bruce H. Vaughn, Donald E. Voigt, Gifford J. Wong, Kendrick C. Taylor

All Materials

On 1 December 2011 the West Antarctic Ice Sheet (WAIS) Divide ice-core project reached its final depth of 3405 m. The WAIS Divide ice core is not only the longest US ice core to date, but is also the highest-quality deep ice core, including ice from the brittle ice zone, that the US has ever recovered. The methods used at WAIS Divide to handle and log the drilled ice, the procedures used to safely retrograde the ice back to the US National Ice Core Laboratory (NICL) and the methods used to process and sample the ice at the NICL are …


Arctic Air Pollution: New Insights From Polarcat-Ipy, Katherine S. Law, Andreas Stohl, Patricia K. Quinn, Charles A. Brock, John F. Burkhart, Jean-Daniel Paris, Gerard Ancellet, Hanwant B. Singh, Anke Roiger, Hans Schlager, Jack E. Dibb, Daniel J. Jacob, S R. Arnold, Jacques Pelon, Jennie L. Thomas Dec 2014

Arctic Air Pollution: New Insights From Polarcat-Ipy, Katherine S. Law, Andreas Stohl, Patricia K. Quinn, Charles A. Brock, John F. Burkhart, Jean-Daniel Paris, Gerard Ancellet, Hanwant B. Singh, Anke Roiger, Hans Schlager, Jack E. Dibb, Daniel J. Jacob, S R. Arnold, Jacques Pelon, Jennie L. Thomas

Earth Sciences

Given the rapid nature of climate change occurring in the Arctic and the difficulty climate models have in quantitatively reproducing observed changes such as sea ice loss, it is important to improve understanding of the processes leading to climate change in this region, including the role of short-lived climate pollutants such as aerosols and ozone. It has long been known that pollution produced from emissions at midlatitudes can be transported to the Arctic, resulting in a winter/spring aerosol maximum known as Arctic haze. However, many uncertainties remain about the composition and origin of Arctic pollution throughout the troposphere; for example, …


Nippon Foundation / Gebco Indian Ocean Bathymetric Compilation Project, Rochelle A. Wigley, Norhizam Hassan, Mohammad Chowdhury, Roshan Ranaweera, Xinh Le Sy, Hemanaden Runghen, Jan Erik Arndt Dec 2014

Nippon Foundation / Gebco Indian Ocean Bathymetric Compilation Project, Rochelle A. Wigley, Norhizam Hassan, Mohammad Chowdhury, Roshan Ranaweera, Xinh Le Sy, Hemanaden Runghen, Jan Erik Arndt

Center for Coastal and Ocean Mapping

The Indian Ocean Bathymetric Compilation (IOBC) project, undertaken by Nippon Foundation / GEBCO Scholars, is focused on building a regional bathymetric data compilation, of all publically-available bathymetric data within the Indian Ocean region from 30°N to 60° S and 10° to 147° E. One of the objectives of this project is the creation of a network of Nippon Foundation / GEBCO Scholars working together, derived from the thirty Scholars from fourteen nations bordering on the Indian Ocean who have graduated from this Postgraduate Certificate in Ocean Bathymetry (PCOB) training program training program at the University of New Hampshire. The IOBC …


Citizen Science Reveals Widespread Negative Effects Of Roads On Amphibian Distributions, Bradley J. Cosentino, David M. Marsh, Kara S. Jones, Joseph J. Apodaca, Christopher Bates, Jessica Beach, Karen H. Beard, Kelsie Becklin, Jane Margaret Bell, Christopher Crockett, George Fawson, Jennifer Fjelsted, Elizabeth A. Forys, Kristen S. Genet, Melanie Grover, Jaimie Holmes, Katherine Indeck, Nancy E. Karraker, Eran S. Kilpatrick, Tom A. Langen, Stephen G. Mugel, Alessandro Molina, James R. Vonesh, Ryan J. Weaver, Anisha Willey Dec 2014

Citizen Science Reveals Widespread Negative Effects Of Roads On Amphibian Distributions, Bradley J. Cosentino, David M. Marsh, Kara S. Jones, Joseph J. Apodaca, Christopher Bates, Jessica Beach, Karen H. Beard, Kelsie Becklin, Jane Margaret Bell, Christopher Crockett, George Fawson, Jennifer Fjelsted, Elizabeth A. Forys, Kristen S. Genet, Melanie Grover, Jaimie Holmes, Katherine Indeck, Nancy E. Karraker, Eran S. Kilpatrick, Tom A. Langen, Stephen G. Mugel, Alessandro Molina, James R. Vonesh, Ryan J. Weaver, Anisha Willey

Wildland Resources Faculty Publications

Landscape structure is important for shaping the abundance and distribution of amphibians, but prior studies of landscape effects have been species or ecosystem-specific. Using a large-scale, citizen science-generated database, we examined the effects of habitat composition, road disturbance, and habitat split (i.e. the isolation of wetland from forest by intervening land use) on the distribution and richness of frogs and toads in the eastern and central United States. Undergraduates from nine biology and environmental science courses collated occupancy data and characterized landscape structure at 1617 sampling locations from the North American Amphibian Monitoring Program. Our analysis revealed that anuran species …


Aminooxy Reagents In Nanomedicine And Bioanalysis., Stephanie Mattingly Dec 2014

Aminooxy Reagents In Nanomedicine And Bioanalysis., Stephanie Mattingly

Electronic Theses and Dissertations

The development of nanomaterials as medical diagnostic and therapeutic agents is a rapidly expanding field. A brief search of the literature revealed that roughly half of all articles related to nanoparticle-based drug delivery were published after the onset of this thesis research, over the past 4 years. A few nano-based formulations have entered into clinical use, including liposomal drug formulations, protein-linked drugs, and nanoparticle-based MRI contrast agents. The chemistry that enables conjugation of a functional cargo, whether a drug, a targeting element, or a radionucleotide, to a nanocarrier is thus a critical component for development. Oximation is one of the …


Triggered Release Of Small Molecules From Solid Supports Using Heat Or An Applied Magnetic Field., Ralph Jacob Knipp Dec 2014

Triggered Release Of Small Molecules From Solid Supports Using Heat Or An Applied Magnetic Field., Ralph Jacob Knipp

Electronic Theses and Dissertations

The reaction of an aminooxy moiety (RONH2) with an aldehyde or ketone carbonyl, an oximation reaction, results in the formation of robust oxime ether linkages. Oximation is a form of click chemistry and is chemoselective, occurs in a variety of solvents including water, and produces high yields with little to no purification. We were inspired to exploit the advantages of oximation reactions by attaching aminooxy-functionalized molecules to solid supports, thus allowing us to employ aminooxy chemistry in ways that cannot be achieved using solution phase. Chapter 1 provides a review of aminooxy chemistry, its advantages over similar reactions and its …


Investigating Mesospheric Gravity Wave Dynamics Over Mcmurdo Station, Antarctica (77° S), Jonathan Pugmire, Michael J. Taylor, Yucheng Zhao, Dominique Pautet Dec 2014

Investigating Mesospheric Gravity Wave Dynamics Over Mcmurdo Station, Antarctica (77° S), Jonathan Pugmire, Michael J. Taylor, Yucheng Zhao, Dominique Pautet

Graduate Student Posters

The ANtarctic Gravity Wave Instrument Network (ANGWIN) is an NSF sponsored international program designed to develop and utilize a network of gravity wave observatories using existing and new instrumentation operated at several established research stations around the continent. The primary goal is to better understand and quantify large-scale gravity wave climatology and their effects on the upper atmosphere over Antarctica. ANGWIN currently comprises research measurements from five nations (U.S., U.K., Australia, Japan, and Brazil) at seven international stations. Utah State University’s Atmospheric Imaging Lab operates an all-sky CCD, all-sky infrared imagers and an Advanced Mesospheric Temperature Mapper (AMTM) imager at …


The National Science Foundation's Coupling, Energetics And Dynamics Of Atmospheric Regions (Cedar) Student Community, Leda Sox, Timothy Duly, Barbara Emery Dec 2014

The National Science Foundation's Coupling, Energetics And Dynamics Of Atmospheric Regions (Cedar) Student Community, Leda Sox, Timothy Duly, Barbara Emery

Physics Student Research

The National Science Foundation sponsors Coupling, Energetics, and Dynamics of Atmospheric Regions (CEDAR) Workshops, which have been held every summer, for the past 27 years. CEDAR Workshops are on the order of a week long and at various locations that are close to university campuses where CEDAR type scientific research is done. Although there is no formal student group within the CEDAR community, the workshops are very student-focused. Roughly half the Workshop participants are students. There are two Student Representatives on the CEDAR Science Steering Committee (CSSC), the group of scientists who organize the CEDAR Workshops. Each Student Representative is …


Contribution Of Multidomain Titanomagnetite To The Intensity And Stability Of Mars Crustal Magnetic Anomalies, Stefanie A. Brachfeld, David Cuomo, Lisa Tatsumi-Petrochilos, Julie A. Bowles, Deepa Shah, Julia Hammer Dec 2014

Contribution Of Multidomain Titanomagnetite To The Intensity And Stability Of Mars Crustal Magnetic Anomalies, Stefanie A. Brachfeld, David Cuomo, Lisa Tatsumi-Petrochilos, Julie A. Bowles, Deepa Shah, Julia Hammer

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Two basalts with compositions relevant to the crusts of Mars and Earth were synthesized at igneous temperatures and held at 650°C for 21 to 257 days under quartz‐fayalite‐magnetite fO2 buffer conditions. The run products are germane to slowly cooled igneous intrusions, which might be a significant volumetric fraction of the Martian crust and carriers of magnetic anomalies in the Southern Highlands. Both basalts acquired intense thermoremanent magnetizations and intense but easily demagnetized anhysteretic remanent magnetizations carried by homogeneous multidomain titanomagnetite. Hypothetical intrusions on Mars composed of these materials would be capable of acquiring intense remanences sufficient to generate the …


Quantifying The Relative Contributions Of Substorm Injections And Chorus Waves To The Rapid Outward Extension Of Electron Radiation Belt, Q. Zong, C A. Kletzing, W. S. Kurth, G. B. Hospodarsky, Harlan E. Spence, Geoffrey Reeves, H. O. Funsten, J. B. Blake, D. N. Baker Dec 2014

Quantifying The Relative Contributions Of Substorm Injections And Chorus Waves To The Rapid Outward Extension Of Electron Radiation Belt, Q. Zong, C A. Kletzing, W. S. Kurth, G. B. Hospodarsky, Harlan E. Spence, Geoffrey Reeves, H. O. Funsten, J. B. Blake, D. N. Baker

Physics & Astronomy

Abstract

We study the rapid outward extension of the electron radiation belt on a timescale of several hours during three events observed by Radiation Belt Storm Probes and Time History of Events and Macroscale Interactions during Substorms satellites and particularly quantify the contributions of substorm injections and chorus waves to the electron flux enhancement near the outer boundary of radiation belt. A comprehensive analysis including both observations and simulations is performed for the first event on 26 May 2013. The outer boundary of electron radiation belt moved from L = 5.5 to L > 6.07 over about 6 h, with up …


Full Issue, The Mcnair Team Dec 2014

Full Issue, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Alumni Earning Doctorates, The Mcnair Team Dec 2014

Alumni Earning Doctorates, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Qmethod: A Package To Explore Human Perspectives Using Q Methodology, Aiora Zabala Dec 2014

Qmethod: A Package To Explore Human Perspectives Using Q Methodology, Aiora Zabala

The R Journal

Q is a methodology to explore the distinct subjective perspectives that exist within a group. It is used increasingly across disciplines. The methodology is semi-qualitative and the data are analysed using data reduction methods to discern the existing patterns of thought. This package is the first to perform Q analysis in R, and it provides many advantages to the existing software: namely, it is fully cross-platform, the algorithms can be transparently examined, it provides results in a clearly structured and tabulated form ready for further exploration and modelling, it produces a graphical summary of the results, and it generates a …


Farewell's Linear Increments Model For Missing Data: The Flim Package, Rune Hoff, Jon Michael Gran, Daniel Farewell Dec 2014

Farewell's Linear Increments Model For Missing Data: The Flim Package, Rune Hoff, Jon Michael Gran, Daniel Farewell

The R Journal

Missing data is common in longitudinal studies. We present a package for Farewell’s Linear Increments Model for Missing Data (the FLIM package), which can be used to fit linear models for observed increments of longitudinal processes and impute missing data. The method is valid for data with regular observation patterns. The end result is a list of fitted models and a hypothetical complete dataset corresponding to the data we might have observed had individuals not been missing. The FLIM package may also be applied to longitudinal studies for causal analysis, by considering counterfactual data as missing data- for instance to …


Flexible R Functions For Processing Accelerometer Data, With Emphasis On Nhanes 2003–2006, Dane R. Van Domelen, W. Stephen Pittard Dec 2014

Flexible R Functions For Processing Accelerometer Data, With Emphasis On Nhanes 2003–2006, Dane R. Van Domelen, W. Stephen Pittard

The R Journal

Accelerometers are a valuable tool for measuring physical activity (PA) in epidemiological studies. However, considerable processing is needed to convert time-series accelerometer data into meaningful variables for statistical analysis. This article describes two recently developed R packages for processing accelerometer data. The package accelerometry contains functions for performing various data processing procedures, such as identifying periods of non-wear time and bouts of activity. The functions are flexible, computationally efficient, and compatible with uniaxial or triaxial data. The package nhanesaccel is specifically for processing data from the National Health and Nutrition Examination Survey (NHANES), years 2003–2006. Its primary function generates measures …


Automatic Conversion Of Tables To Longform Dataframes, Jimmy Oh Dec 2014

Automatic Conversion Of Tables To Longform Dataframes, Jimmy Oh

The R Journal

TableToLongForm automatically converts hierarchical Tables intended for a human reader into a simple LongForm dataframe that is machine readable, making it easier to access and use the data for analysis. It does this by recognising positional cues present in the hierarchical Table (which would normally be interpreted visually by the human brain) to decompose, then reconstruct the data into a LongForm dataframe. The article motivates the benefit of such a conversion with an example Table, followed by a short user manual, which includes a comparison between the simple one argument call to TableToLongForm, with code for an equivalent manual conversion. …


Gset: An R Package For Exact Sequential Test Of Equivalence Hypothesis Based On Bivariate Non-Central T-Statistics, Fang Liu Dec 2014

Gset: An R Package For Exact Sequential Test Of Equivalence Hypothesis Based On Bivariate Non-Central T-Statistics, Fang Liu

The R Journal

The R package gset calculates equivalence and futility boundaries based on the exact bivariate non-central t test statistics. It is the first R package that targets specifically at the group sequential test of equivalence hypotheses. The exact test approach adopted by gset neither assumes the large-sample normality of the test statistics nor ignores the contribution to the overall Type I error rate from rejecting one out of the two one-sided hypotheses under a null value. The features of gset include: error spending functions, computation of equivalence boundaries and futility boundaries, either binding or nonbinding, depiction of stagewise boundary plots, and …