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Articles 138811 - 138840 of 303797

Full-Text Articles in Physical Sciences and Mathematics

A Review Of Structural Patterns And Melting Processes In The Archean Craton Of West Greenland: Evidence For Crustal Growth At Convergent Plate Margins As Opposed To Non-Uniformitarian Models, Ali Polat Nov 2015

A Review Of Structural Patterns And Melting Processes In The Archean Craton Of West Greenland: Evidence For Crustal Growth At Convergent Plate Margins As Opposed To Non-Uniformitarian Models, Ali Polat

Earth & Environmental Sciences Publications

The Archean craton of West Greenland consists of many fault-bounded Eoarchean to Neoarchean tectonic terranes (crustal blocks). These tectonic terranes are composed mainly of tonalite-trondhjemite-granodiorite (TTG) gneisses, granitic gneisses, metavolcanic-dominated supracrustal belts, layered anorthositic complexes, and late- to post-tectonic granites. Rock assemblages and geochemical signatures in these terranes suggest that they represent fragments of dismembered oceanic island arcs, consisting mainly of TTG plutons, tholeiitic to calc-alkaline basalts, boninites, picrites, and cumulate layers of ultramafic rocks, gabbros, leucogabbros and anorthosites, with minor sedimentary rocks. The structural characteristics of the terrane boundaries are consistent with the assembly of these island arcs through …

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Effect Of Sm Content On Energy Product Of Rapidly Quenched And Oriented Smco5 Ribbons, Wenyong Zhang, Xingzhong Li, Shah R. Valloppilly Nov 2015

Effect Of Sm Content On Energy Product Of Rapidly Quenched And Oriented Smco5 Ribbons, Wenyong Zhang, Xingzhong Li, Shah R. Valloppilly

Nebraska Center for Materials and Nanoscience: Faculty Publications

The Sm-content dependence of phase composition, anisotropy, and other magnetic properties of Sm1+δCo5 (δ ≤ 0.12) ribbons melt spun at 10 m/s has been studied. The samples consist of hexagonal SmCo5 grains whose c axes are preferentially aligned along the long direction of the ribbon. The lattice parameter a and the cell volume (V) increase with increasing Sm content δ, whereas c decreases. Sm addition appears to improve the degree of the preferred orientation of the c-axis and to increase the mean grain size, which weakens the effective intergranular exchange …

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Wintertime Weather-Climate Variability And Its Links To Early Spring Ice-Out In Maine Lakes, Mussie Beyene, Shaleen Jain Nov 2015

Wintertime Weather-Climate Variability And Its Links To Early Spring Ice-Out In Maine Lakes, Mussie Beyene, Shaleen Jain

Publications

In recent decades, Maine lakes have recorded their earliest ice-out dates in over a century. In temperate regions, seasonal lake ice-cover is a critical phenomenon linking climate, aquatic ecosystem and society. And the lengthening of the ice-free period due to warmer climate has been linked to increased algal growth and declining lake water quality, warming of water temperatures leading to alterations in aquatic biodiversity, and the shortening of ice-fishing period and other traditional winter activities over lakes. In this study, historical record of eight lakes and six benchmarked meteorological stations in Maine for the period 1950–2010 were analyzed to (1) …

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8000 Years Of Environmental Evolution Of Barrier–Lagoon Systems Emplaced In Coastal Embayments (Nw Iberia), Rita González-Villanueva, Marta Pérez-Arlucea, Susana Costas, Roberto Bao, Xose L. Otero, Ronald J. Goble Nov 2015

8000 Years Of Environmental Evolution Of Barrier–Lagoon Systems Emplaced In Coastal Embayments (Nw Iberia), Rita González-Villanueva, Marta Pérez-Arlucea, Susana Costas, Roberto Bao, Xose L. Otero, Ronald J. Goble

Department of Earth and Atmospheric Sciences: Faculty Publications

The rocky and indented coast of NW Iberia is characterized by the presence of highly valuable and vulnerable, small and shallow barrier– lagoon systems structurally controlled. The case study was selected to analyse barrier–lagoon evolution based on detailed sedimentary architecture, chronology, geochemical and biological proxies. The main objective is to test the hypothesis of structural control and the significance at regional scale of any highenergy event recorded. This work is also aimed at identifying general patterns and conceptualizing the formation and evolution of this type of coastal systems. The results allowed us to establish a conceptual model of Holocene evolution …

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Approaches For Detection Of Unstable Processes: A Comparative Study, Yerriswamy Wooluru, D. R. Swamy, P. Nagesh Nov 2015

Approaches For Detection Of Unstable Processes: A Comparative Study, Yerriswamy Wooluru, D. R. Swamy, P. Nagesh

Journal of Modern Applied Statistical Methods

A process is stable only when parameters of the distribution of a process or product characteristic remain same over time. Only a stable process has the ability to perform in a predictable manner over time. Statistical analysis of process data usually assume that data are obtained from stable process. In the absence of control charts, the hypothesis of process stability is usually assessed by visual examination of the pattern in the run chart. In this paper appropriate statistical approaches have been adopted to detect instability in the process and compared their performance with the run chart of considerably shorter length …

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2015: "Go With The Flow", Paul Nebres '16, Kushagra Gupta '16, Jason Chen '16, Noor Michael '16 Nov 2015

2015: "Go With The Flow", Paul Nebres '16, Kushagra Gupta '16, Jason Chen '16, Noor Michael '16

Distinguished Student Work

In a famous incident in August 2010, a Chinese traffic jam stretched for over 100 kilometers and stranded drivers took over two weeks to get from one side to the other. Stemming from a routine lane closure for road maintenance, the traffic jam soon spiraled out of control, as cars piling up at the jam greatly outnumbered those leaving the other end. Sadly, in todays overpopulated world, these sorts of nightmare scenarios are only becoming more and more common, from chronic traffic jams in congested Chinese cities to Carmageddon in Los Angeles. For drivers, these extensive traffic jams can be …

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Distributions Of Long-Lived Radioactive Nuclei Provided By Star-Forming Environments, Marco Fatuzzo, Fred Adams Nov 2015

Distributions Of Long-Lived Radioactive Nuclei Provided By Star-Forming Environments, Marco Fatuzzo, Fred Adams

Faculty Scholarship

Radioactive nuclei play an important role in planetary evolution by providing an internal heat source, which affects planetary structure and helps facilitate plate tectonics. A minimum level of nuclear activity is thought to be necessary—but not sufficient—for planets to be habitable. Extending previous work that focused on short-lived nuclei, this paper considers the delivery of long-lived radioactive nuclei to circumstellar disks in star forming regions. Although the long-lived nuclear species are always present, their abundances can be enhanced through multiple mechanisms. Most stars form in embedded cluster environments, so that disks can be enriched directly by intercepting ejecta from supernovae …

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40ar/39ar Ages Of Lunar Impact Glasses: Relationships Among Ar Diffusivity, Chemical Composition, Shape, And Size, John W. Delano Phd, Nicolle Zellner Nov 2015

40ar/39ar Ages Of Lunar Impact Glasses: Relationships Among Ar Diffusivity, Chemical Composition, Shape, And Size, John W. Delano Phd, Nicolle Zellner

Atmospheric and Environmental Science Faculty Scholarship

Lunar impact glasses, which are quenched melts produced during cratering events on the Moon, have the potential to providenot only compositional information about both the local and regional geology of the Moon but also information about the impact flux over time. We present in this paper the results of 73 new 40Ar/39Ar analyses of well-characterized, inclusion-free lunar impact glasses and demonstrate that size, shape, chemical composition, fraction of radiogenic 40Ar retained, and cosmic ray exposure (CRE) ages are important for 40Ar/39Ar investigations of these samples. Specifically, analyses of lunar impact glasses from the Apollo 14, 16, and 17 landing sites …

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Measurement Of Interaction Between Antiprotons, Adam Gibson-Even, Shirvel Stanislaus, Donald Koetke, Star Collaboration Nov 2015

Measurement Of Interaction Between Antiprotons, Adam Gibson-Even, Shirvel Stanislaus, Donald Koetke, Star Collaboration

Physics and Astronomy Faculty Publications

No abstract provided.

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West Coast Deep Sea Crustacean Managed Fishery, Jason R. How, F J. Webster, K. L. Travaille, Kim Nardi, A. V. Harry Nov 2015

West Coast Deep Sea Crustacean Managed Fishery, Jason R. How, F J. Webster, K. L. Travaille, Kim Nardi, A. V. Harry

WA Marine Stewardship Council report series

This report provides a comprehensive description of the West Coast Deep Sea Crustacean Managed Fishery (WCDSCMF) and contains information relevant to assist the assessment of this fishery against the Marine Stewardship Council (MSC) standard (v1.3) for sustainable fishing.

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Searches For Continuous Gravitational Waves From Nine Young Supernova Remnants, J. Aasi, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, Marc Favata, Shaon Ghosh, Rodica Martin Nov 2015

Searches For Continuous Gravitational Waves From Nine Young Supernova Remnants, J. Aasi, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We describe directed searches for continuous gravitational waves (GWs) in data from the sixth Laser Interferometer Gravitational-wave Observatory (LIGO) science data run. The targets were nine young supernova remnants not associated with pulsars; eight of the remnants are associated with non-pulsing suspected neutron stars. One target's parameters are uncertain enough to warrant two searches, for a total of 10. Each search covered a broad band of frequencies and first and second frequency derivatives for a fixed sky direction. The searches coherently integrated data from the two LIGO interferometers over time spans from 5.3-25.3 days using the matched-filtering -statistic. We found …

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Smart Sensing And Mobile Computing, Guihai Chen, Dakshnamoorthy Manivannan, Chen Qian, Fangming Liu, Jinsong Han Nov 2015

Smart Sensing And Mobile Computing, Guihai Chen, Dakshnamoorthy Manivannan, Chen Qian, Fangming Liu, Jinsong Han

Computer Science Faculty Publications

No abstract provided.

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Contrails: Causal Inference Using Propensity Scores, Dean S. Barron Nov 2015

Contrails: Causal Inference Using Propensity Scores, Dean S. Barron

Journal of Modern Applied Statistical Methods

Contrails are clouds caused by airplane exhausts, which geologists contend decrease daily temperature ranges on Earth. Following the 2001 World Trade Center attack, cancelled domestic flights triggered the first absence of contrails in decades. Resultant exceptional data capacitated causal inference analysis by propensity score matching. Estimated contrail effect was 6.8981°F.

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The Bayes Factor For Case-Control Studies With Misclassified Data, Tzesan Lee Nov 2015

The Bayes Factor For Case-Control Studies With Misclassified Data, Tzesan Lee

Journal of Modern Applied Statistical Methods

The question of how to test if collected data for a case-control study are misclassified was investigated. A mixed approach was employed to calculate the Bayes factor to assess the validity of the null hypothesis of no-misclassification. A real-world data set on the association between lung cancer and smoking status was used as an example to illustrate the proposed method.

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Bayesian Analysis Under Progressively Censored Rayleigh Data, Gyan Prakash Nov 2015

Bayesian Analysis Under Progressively Censored Rayleigh Data, Gyan Prakash

Journal of Modern Applied Statistical Methods

The one-parameter Rayleigh model is considered as an underlying model for evaluating the properties of Bayes estimator under Progressive Type-II right censored data. The One‑Sample Bayes prediction bound length (OSBPBL) is also measured. Based on two different asymmetric loss functions a comparative study presented for Bayes estimation. A simulation study was used to evaluate their comparative properties.

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An Empirical Study On Different Ranking Methods For Effective Data Classification, Ilangovan Sangaiah, A. Vincent Antony Kumar, Appavu Balamurugan Nov 2015

An Empirical Study On Different Ranking Methods For Effective Data Classification, Ilangovan Sangaiah, A. Vincent Antony Kumar, Appavu Balamurugan

Journal of Modern Applied Statistical Methods

Ranking is the attribute selection technique used in the pre-processing phase to emphasize the most relevant attributes which allow models of classification simpler and easy to understand. It is a very important and a central task for information retrieval, such as web search engines, recommendation systems, and advertisement systems. A comparison between eight ranking methods was conducted. Ten different learning algorithms (NaiveBayes, J48, SMO, JRIP, Decision table, RandomForest, Multilayerperceptron, Kstar) were used to test the accuracy. The ranking methods with different supervised learning algorithms give different results for balanced accuracy. It was shown the selection of ranking methods could be …

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Two Stage Robust Ridge Method In A Linear Regression Model, Adewale Folaranmi Lukman, Oyedeji Isola Osowole, Kayode Ayinde Nov 2015

Two Stage Robust Ridge Method In A Linear Regression Model, Adewale Folaranmi Lukman, Oyedeji Isola Osowole, Kayode Ayinde

Journal of Modern Applied Statistical Methods

Two Stage Robust Ridge Estimators based on robust estimators M, MM, S, LTS are examined in the presence of autocorrelation, multicollinearity and outliers as alternative to Ordinary Least Square Estimator (OLS). The estimator based on S estimator performs better. Mean square error was used as a criterion for examining the performances of these estimators.

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Semi-Parametric Non-Proportional Hazard Model With Time Varying Covariate, Kazeem A. Adeleke, Alfred A. Abiodun, R. A. Ipinyomi Nov 2015

Semi-Parametric Non-Proportional Hazard Model With Time Varying Covariate, Kazeem A. Adeleke, Alfred A. Abiodun, R. A. Ipinyomi

Journal of Modern Applied Statistical Methods

The application of survival analysis has extended the importance of statistical methods for time to event data that incorporate time dependent covariates. The Cox proportional hazards model is one such method that is widely used. An extension of the Cox model with time-dependent covariates was adopted when proportionality assumption are violated. The purpose of this study is to validate the model assumption when hazard rate varies with time. This approach is applied to model data on duration of infertility subject to time varying covariate. Validity is assessed by a set of simulation experiments and results indicate that a non proportional …

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Structural Properties Of Transmuted Weibull Distribution, Kaisar Ahmad, S. P. Ahmad, A. Ahmed Nov 2015

Structural Properties Of Transmuted Weibull Distribution, Kaisar Ahmad, S. P. Ahmad, A. Ahmed

Journal of Modern Applied Statistical Methods

The transmuted Weibull distribution, and a related special case, is introduced. Estimates of parameters are obtained by using a new method of moments.

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New Entropy Estimators With Smaller Root Mean Squared Error, Amer Ibrahim Al-Omari Nov 2015

New Entropy Estimators With Smaller Root Mean Squared Error, Amer Ibrahim Al-Omari

Journal of Modern Applied Statistical Methods

New estimators of entropy of continuous random variable are suggested. The proposed estimators are investigated under simple random sampling (SRS), ranked set sampling (RSS), and double ranked set sampling (DRSS) methods. The estimators are compared with Vasicek (1976) and Al-Omari (2014) entropy estimators theoretically and by simulation in terms of the root mean squared error (RMSE) and bias values. The results indicate that the suggested estimators have less RMSE and bias values than their competing estimators introduced by Vasicek (1976) and Al-Omari (2014).

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Caution For Software Use Of New Statistical Methods (R), Akiva J. Lorenz, Barry S. Markman, Shlomo Sawilowsky Nov 2015

Caution For Software Use Of New Statistical Methods (R), Akiva J. Lorenz, Barry S. Markman, Shlomo Sawilowsky

Journal of Modern Applied Statistical Methods

Open source programming languages such as R allow statisticians to develop and rapidly disseminate advanced procedures, but sometimes at the expense of a proper vetting process. A new example is the least trimmed squares regression available in R’s lqs() in the MASS library. It produces pretty regression lines, particularly in the presence of outliers. However, this procedure lacks a defined standard error, and thus it should be avoided.

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Inferences About The Skipped Correlation Coefficient: Dealing With Heteroscedasticity And Non-Normality, Rand Wilcox Nov 2015

Inferences About The Skipped Correlation Coefficient: Dealing With Heteroscedasticity And Non-Normality, Rand Wilcox

Journal of Modern Applied Statistical Methods

A common goal is testing the hypothesis that Pearson’s correlation is zero and typically this is done based on Student’s T test. There are, however, several well-known concerns. First, Student’s T is sensitive to heteroscedasticity. That is, when it rejects, it is reasonable to conclude that there is dependence, but in terms of making a decision about the strength of the association, it is unsatisfactory. Second, Pearson’s correlation is not robust: it can poorly reflect the strength of the association. Even a single outlier can have a tremendous impact on the usual estimate of Pearson’s correlation, which can result in …

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In (Partial) Defense Of .05, Thomas R. Knapp Nov 2015

In (Partial) Defense Of .05, Thomas R. Knapp

Journal of Modern Applied Statistical Methods

Researchers are frequently chided for choosing the .05 alpha level as the determiner of statistical significance (or non-significance). A partial justification is provided.

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The Distribution Of The Inverse Square Root Transformed Error Component Of The Multiplicative Time Series Model, Bright F. Ajibade, Chinwe R. Nwosu, J. I. Mbegdu Nov 2015

The Distribution Of The Inverse Square Root Transformed Error Component Of The Multiplicative Time Series Model, Bright F. Ajibade, Chinwe R. Nwosu, J. I. Mbegdu

Journal of Modern Applied Statistical Methods

The probability density function, mean and variance of the inverse square-root transformed left-truncated N(1,σ2) error component e*t(=1/ √et) of the multiplicative time series model were established. A comparison of key-statistical properties of e*t and et confirmed normality with mean 1 but with Var(e*t) ≈1/4Var(et) when σ≤0.14. Hence σ≤0.14 is the required condition for successful transformation.

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Front Matter, Jmasm Editors Nov 2015

Front Matter, Jmasm Editors

Journal of Modern Applied Statistical Methods

.

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Comment On Faa Rule Revision - Transport Category Aircraft, Paul F. Eschenfelder, Valter Battistoni Nov 2015

Comment On Faa Rule Revision - Transport Category Aircraft, Paul F. Eschenfelder, Valter Battistoni

Paul F. Eschenfelder

No abstract provided.

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Candels Visual Classifications: Scheme, Data Release, And First Results, Jeyhan S. Kartaltepe, Mark Mozena, Dale D. Kocevski, Daniel H. Mcintosh, Jennifer Lotz, Eric F. Bell, Sandra M. Faber, Harry C. Ferguson, David C. Koo, Robert Bassett, Maksym Bernyk, Kirsten Blancato, Frederic Bournaud, Paolo Cassata, M. Castellano, Edmond Cheung, Christopher J. Conselice, D. Croton, Tomas Dahlen, Duilia F. De Mello, Laura Degroot, Jennifer Donley, Javiera Guedes, Norman A. Grogin, Nimish Hathi, Matt Hilton, Brett Hollon, Anton M. Koekemoer, Nick Liu, Ray A. Lucas Nov 2015

Candels Visual Classifications: Scheme, Data Release, And First Results, Jeyhan S. Kartaltepe, Mark Mozena, Dale D. Kocevski, Daniel H. Mcintosh, Jennifer Lotz, Eric F. Bell, Sandra M. Faber, Harry C. Ferguson, David C. Koo, Robert Bassett, Maksym Bernyk, Kirsten Blancato, Frederic Bournaud, Paolo Cassata, M. Castellano, Edmond Cheung, Christopher J. Conselice, D. Croton, Tomas Dahlen, Duilia F. De Mello, Laura Degroot, Jennifer Donley, Javiera Guedes, Norman A. Grogin, Nimish Hathi, Matt Hilton, Brett Hollon, Anton M. Koekemoer, Nick Liu, Ray A. Lucas

Physics and Astronomy Faculty Publications

We have undertaken an ambitious program to visually classify all galaxies in the five CANDELS fields down to H < 24.5 involving the dedicated efforts of over 65 individual classifiers. Once completed, we expect to have detailed morphological classifications for over 50,000 galaxies spanning 0 < z < 4 over all the fields, with classifications from 3 to 5 independent classifiers for each galaxy. Here, we present our detailed visual classification scheme, which was designed to cover a wide range of CANDELS science goals. This scheme includes the basic Hubble sequence types, but also includes a detailed look at mergers and interactions, the clumpiness of galaxies, k-corrections, and a variety of other structural properties. In this paper, we focus on the first field to be completed—GOODS-S, which has been classified at various depths. The wide area coverage spanning the full field (wide+deep+ERS) includes 7634 galaxies that have been classified by at least three different people. In the deep area of the field, 2534 galaxies have been classified by at least five different people at three different depths. With this paper, we release to the public …

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From Equations To Tri-Quations And Multi-Quations, Mourat Tchoshanov, Olga Kosheleva, Vladik Kreinovich Nov 2015

From Equations To Tri-Quations And Multi-Quations, Mourat Tchoshanov, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In general, an equation A(x1, ..., xn)= B(x1, ..., xn) corresponds to the situation when we have two quantities A(x1, ..., xn) and B(x1, ..., xn) which are known to be equal, we know how each of these quantities depends on the unknown parameters x1, ..., xn, and we want to find the values of the unknowns xi from this equality -- and from other similar equalities. In some practical situations, instead of two equal values, we have three …

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Why The Graph Isomorphism Problem Is Easier Than Propositional Satisfiability: A Possible Qualitative Explanation, Vladik Kreinovich, Olga Kosheleva Nov 2015

Why The Graph Isomorphism Problem Is Easier Than Propositional Satisfiability: A Possible Qualitative Explanation, Vladik Kreinovich, Olga Kosheleva

Departmental Technical Reports (CS)

A recent result has shown that the graph isomorphism problem can be solved in quasi-polynomial time, while the general belief is that only exponential time algorithms are possible for propositional satisfiability. This is somewhat counter-intuitive, since for propositional satisfiability, we need to look for one of 2n options, while in graph isomorphism, we need to look for one of n! options, and n! is much larger than 2n. Our qualitative explanation for this counter-intuitive fact comes from the fact that, in general, a graph isomorphism problem has a unique solution -- in contrast to propositional satisfiability which, …

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Decision Making Under Interval (And More General) Uncertainty: Monetary Vs. Utility Approaches, Vladik Kreinovich Nov 2015

Decision Making Under Interval (And More General) Uncertainty: Monetary Vs. Utility Approaches, Vladik Kreinovich

Departmental Technical Reports (CS)

In many situations, e.g., in financial and economic decision making, the decision results either in a money gain (or loss) and/or in the gain of goods that can be exchanged for money or for other goods. In such situations, interval uncertainty means that we do not know the exact amount of money that we will get for each possible decision, we only know lower and upper bounds on this amount. In this case, a natural idea is to assign a fair price to different alternatives, and then to use these fair prices to select the best alternative. In the talk, …

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