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2011

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Articles 301 - 330 of 10326

Full-Text Articles in Physical Sciences and Mathematics

Dirty Tricks Played By The Domain Registrars, Umakant Mishra Dec 2011

Dirty Tricks Played By The Domain Registrars, Umakant Mishra

Umakant Mishra

With the popularity of Internet the number of websites are increasing in exponential rate. Everybody needs a website and every website needs a domain name and a hosting server. Domain names often represent a business organization or a commercial brand. Hence, changing domain names may affect business strategy and result in serious business loss. The domain registrars often take advantage of customers’ ignorance and weakness and trouble them to unduly extract more and more money.


The Dirty Tricks Played By Web Hosting Agencies, Umakant Mishra Dec 2011

The Dirty Tricks Played By Web Hosting Agencies, Umakant Mishra

Umakant Mishra

The number of websites are increasing in exponential rate. There are almost 50,000 websites being launched in every week and a similar number of web hosting companies are thriving to grab that opportunity. This has led to a cutthroat competition between the web hosting companies. The competition has gone beyond the ethical boundaries and many of them follow various unfair practices to attract and retain customers.


Time-Dependent Cortical Activation In Voluntary Muscle Contraction, Qi Yang, Xiao-Feng Wang, Yin Fang, Vlodek Siemionow, Wanxiang Yao, Guang H. Yue Dec 2011

Time-Dependent Cortical Activation In Voluntary Muscle Contraction, Qi Yang, Xiao-Feng Wang, Yin Fang, Vlodek Siemionow, Wanxiang Yao, Guang H. Yue

Xiaofeng Wang

This study was to characterize dynamic source strength changes estimated from high-density scalp electroencephalogram (EEG) at different phases of a submaximal voluntary muscle contraction. Eight healthy volunteers performed isometric handgrip contractions of the right arm at 20% maximal intensity. Signals of the handgrip force, electromyography (EMG) from the finger flexor and extensor muscles and 64-channel EEG were acquired simultaneously. Sources of the EEG were analyzed at 19 time points across preparation, execution and sustaining phases of the handgrip. A 3-layer boundary element model (BEM) based on the MNI (Montréal Neurological Institute) brain MRI was used to overlay the sources. A …


Designing Carbon Taxation Schemes For Automobiles: A Simulation Exercise For Germany, Adamos Adamou, Sofronis Clerides, Theodoros Zachariadis Dec 2011

Designing Carbon Taxation Schemes For Automobiles: A Simulation Exercise For Germany, Adamos Adamou, Sofronis Clerides, Theodoros Zachariadis

Theodoros Zachariadis

Vehicle taxation based on CO2 emissions is increasingly being adopted worldwide in order to shift consumer purchases to low-carbon cars, yet little is known about the effectiveness and overall economic impact of these schemes. We focus on feebate schemes, which impose a fee on high-carbon vehicles and give a rebate to purchasers of low-carbon automobiles. We estimate a discrete choice model of demand for automobiles in Germany and simulate the impact of alternative feebate schemes on emissions, consumer welfare, public revenues and firm profits. The analysis shows that a well-designed scheme can lead to emission reductions without reducing overall welfare.


The Value Of Government Mandated Location-Based Services In Emergencies In Australia, Anas Aloudat, Katina Michael, Roba Abbas, Mutaz M. Al-Debei Dec 2011

The Value Of Government Mandated Location-Based Services In Emergencies In Australia, Anas Aloudat, Katina Michael, Roba Abbas, Mutaz M. Al-Debei

Dr. Mutaz M. Al-Debei

The adoption of mobile technologies for emergency management has the capacity to save lives. In Australia in February 2009, the Victorian Bushfires claimed 173 lives, the worst peace-time disaster in the nation’s history. The Australian government responded swiftly to the tragedy by going to tender for mobile applications that could be used during emergencies, such as mobile alerts and location services. These applications, which are becoming increasingly accurate with the evolution of positioning techniques, have the ability to deliver personalized information direct to the citizen during crises, complementing traditional broadcasting mediums like television and radio. Indeed governments have a responsibility …


Lectio Praecursoria, Kari Myöhänen Dec 2011

Lectio Praecursoria, Kari Myöhänen

Kari Myöhänen

Lectio praecursoria: Modelling of combustion and sorbent reactions in three-dimensional flow environment of a circulating fluidized bed furnace


Transient Flow Of A Generalized Second Grade Fluid Due To A Constant Surface Shear Stress: An Approximate Integral-Balance Solution, Jordan Hristov Dec 2011

Transient Flow Of A Generalized Second Grade Fluid Due To A Constant Surface Shear Stress: An Approximate Integral-Balance Solution, Jordan Hristov

Jordan Hristov

Integral balance solution to start-up problem of a second grade viscoelastic fluid caused by a constant surface stress at the surface has been developed by an entire-domain parabolic profile with an unspecified exponent. The closed form solution explicitly defines two dimensionless similarity variables ξ = y ν t and 2 D0 p t= χ = ν β , responsible for the viscous and the elastic responses of the fluid to the step jump at the boundary. Numerical simulations demonstrating the effect of the various operating parameter and fluid properties on the developed flow filed, as well comparison with the existing …


Symmetry-Breaking Bifurcation In The Nonlinear Schrödinger Equation With Symmetric Potentials, E. Kirr, Panos Kevrekidis, D. E. Pelinovsky Dec 2011

Symmetry-Breaking Bifurcation In The Nonlinear Schrödinger Equation With Symmetric Potentials, E. Kirr, Panos Kevrekidis, D. E. Pelinovsky

Panos Kevrekidis

We consider the focusing (attractive) nonlinear Schr\"odinger (NLS) equation with an external, symmetric potential which vanishes at infinity and supports a linear bound state. We prove that the symmetric, nonlinear ground states must undergo a symmetry breaking bifurcation if the potential has a non-degenerate local maxima at zero. Under a generic assumption we show that the bifurcation is either subcritical or supercritical pitchfork. In the particular case of double-well potentials with large separation, the power of nonlinearity determines the subcritical or supercritical character of the bifurcation. The results are obtained from a careful analysis of the spectral properties of the …


Differential Geometry Based Solvation Model Ii: Lagrangian Formulation, Zhan Chen, Nathan A. Baker, Guo-Wei Wei Dec 2011

Differential Geometry Based Solvation Model Ii: Lagrangian Formulation, Zhan Chen, Nathan A. Baker, Guo-Wei Wei

Zhan Chen

Solvation is an elementary process in nature and is of paramount importance to more sophisticated chemical, biological and biomolecular processes. The understanding of solvation is an essential prerequisite for the quantitative description and analysis of biomolecular systems. This work presents a Lagrangian formulation of our differential geometry based solvation models. The Lagrangian representation of biomolecular surfaces has a few utilities/advantages. First, it provides an essential basis for biomolecular visualization, surface electrostatic potential map and visual perception of biomolecules. Additionally, it is consistent with the conventional setting of implicit solvent theories and thus, many existing theoretical algorithms and computational software packages …


Chilling A Hot Planet: Many Solutions, No Answers, Singapore Management University Dec 2011

Chilling A Hot Planet: Many Solutions, No Answers, Singapore Management University

Perspectives@SMU

If there was a report card on how the world is doing on issues related to climate change, it would read a resounding 'F'. Consider the figures. It took about 12,500 years between the last glacial age and today for global temperatures to rise six degrees Celsius. Yet in this century alone – despite heightened awareness of the need to arrest the ever-increasing levels of greenhouse gas emission – temperatures have risen up to four degrees Celsius.


Bifurcation And Invariant Manifolds Of The Logistic Competition Model, M. Guzowska, Rafael Luís, Saber Elaydi Dec 2011

Bifurcation And Invariant Manifolds Of The Logistic Competition Model, M. Guzowska, Rafael Luís, Saber Elaydi

Mathematics Faculty Research

In this paper we study a new logistic competition model. We will investigate stability and bifurcation of the model. In particular, we compute the invariant manifolds, including the important center manifolds, and study their bifurcation. Saddle-node and period doubling bifurcation route to chaos is exhibited via numerical simulations.


Thermodynamics And Phase Transitions For The Heisenberg Model On The Pinwheel Distorted Kagome Lattice, Ehsan Khatami, Rajiv Singh, Marcos Rigol Dec 2011

Thermodynamics And Phase Transitions For The Heisenberg Model On The Pinwheel Distorted Kagome Lattice, Ehsan Khatami, Rajiv Singh, Marcos Rigol

Faculty Publications

We study the Heisenberg model on the pinwheel distorted kagome lattice as observed in the material Rb2Cu3SnF12. Experimentally relevant thermodynamic properties at finite temperatures are computed utilizing numerical linked-cluster expansions. We also develop a Lanczos-based, zero-temperature, numerical linked-cluster expansion to study the approach of the pinwheel distorted lattice to the uniform kagome-lattice Heisenberg model. We find strong evidence for a phase transition before the uniform limit is reached, implying that the ground state of the kagome-lattice Heisenberg model is likely not pinwheel dimerized and is stable to finite pinwheel-dimerizing perturbations.


Mobile Phone Graph Evolution: Findings, Model And Interpretation, Siyuan Liu, Lei Li, Christos Faloutsos, Lionel M. Ni Dec 2011

Mobile Phone Graph Evolution: Findings, Model And Interpretation, Siyuan Liu, Lei Li, Christos Faloutsos, Lionel M. Ni

LARC Research Publications

What are the features of mobile phone graph along the time? How to model these features? What are the interpretation for the evolutional graph generation process? To answer the above challenging problems, we analyze a massive who-call-whom networks as long as a year, gathered from records of two large mobile phone communication networks both with 2 million users and 2 billion of calls. We examine the calling behavior distribution at multiple time scales (e.g. day, week, month and quarter), and find that the distribution is not only skewed with a heavy tail, but also changing at different time scales. How …


Development Of A Glycoconjugate Tool Set For The Assembly And Presentation Of Carbohydrate Ligands On Surfaces, Irene Esah Abia Dec 2011

Development Of A Glycoconjugate Tool Set For The Assembly And Presentation Of Carbohydrate Ligands On Surfaces, Irene Esah Abia

Doctoral Dissertations

Carbohydrate and protein interactions are often essential in viral and bacterial infection, the immune response, cell differentiation and development, and the progression of tumor cell metastasis. Therefore, an understanding of carbohydrate–protein interactions at the molecular level would lead to a better insight into the biological process of living systems and assist in the development of therapeutic and diagnostic strategies. Our goal was to synthesize different mannose derivatives, immobilize them on nano-patterned surfaces and carry out binding studies with mannose-binding lectins in order to characterize carbohydrate–protein interactions.

Different derivatives of D-mannose (monosaccharide, (1→2)-linked disaccharide, (1→3)-linked disaccharide, and (1→2, 1→3)-linked trisaccharide) with …


Outlier Detection Using Modified-Ranks And Other Variants, Huaming Huang, Kishan Mehrotra, Chilukuri K. Mohan Dec 2011

Outlier Detection Using Modified-Ranks And Other Variants, Huaming Huang, Kishan Mehrotra, Chilukuri K. Mohan

Electrical Engineering and Computer Science - Technical Reports

Rank based algorithms provide a promising approach for outlier detection, but currently used rank-based measures of outlier detection suffer from two deficiencies: first they take a large value from an object whose density is high even though the object may not be an outlier and second the distance between the object and its nearest cluster plays a mild role though its rank with respect to its neighbor. To correct for these deficiencies we introduce the concept of modified-rank and propose new algorithms for outlier detection based on this concept.


A Distributed Approach For Fault Mitigation In Large Scale Distributed Systems, Mina Jung Dec 2011

A Distributed Approach For Fault Mitigation In Large Scale Distributed Systems, Mina Jung

Electrical Engineering and Computer Science - Dissertations

In a large scale real-time distributed system, a large number of components and the time criticality of tasks can contribute to complex situations. Providing predictable and reliable service is a paramount interest in such a system. For example, a single point failure in an electric grid system may lead to a widespread power outage like the Northeast Blackout of 2003. System design and implementation address fault avoidance and mitigation. However, not all faults and failures can be removed during these phases, and therefore run-time fault avoidance and mitigation are needed during the operation. Timing constraints and predictability of the system …


Citrate Binding To The Membrane Protein Proteorhodopsin, Farhana F. Syed Dec 2011

Citrate Binding To The Membrane Protein Proteorhodopsin, Farhana F. Syed

Chemistry - Dissertations

Proteorhodopsin (pR) is an intrinsic membrane protein with an important role in solar-energy storage of the biosphere. Earlier work in our lab has shown that polyhistidine-tagged pR can be purified by means of selective precipitation with citrate under specific conditions, as can a number of mutants based on this His6-tagged pR. Purification of a heterologously-expressed trans-membrane protein by a simple salt such as citrate is novel. However, such a phenomenon leads to several questions: How does citrate cause pR precipitation? Does the polyhistidine-tag assist in such a precipitation? Is this precipitation pH-specific? Does citrate affect the function of …


Controlling Biofouling By Surface Engineering And Molecular Inhibition, Debjyoti Bandyopadhyay Dec 2011

Controlling Biofouling By Surface Engineering And Molecular Inhibition, Debjyoti Bandyopadhyay

Chemistry - Dissertations

The common theme that binds together all the chapters in this dissertation is anti-biofouling chemistry. By utilizing tools of surface engineering and molecular inhibition, a hypothesis driven, systematic approach of controlling the different forms of biofoulings such as protein adsorption, mammalian cell adhesion and biofilm formation is presented. Chapter 1 provides a brief introduction about topics relevant for understanding the studies presented in subsequent chapters. Chapter 2 reports the synthesis of enantiomerically pure alkanethiols that terminate with different stereoisomer's of sugar alcohols, and the effect of chirality of these polyol-terminated self-assembled monolayers (SAMs) on resisting protein adsorption.

Chapter 3 …


The Design And Construction Of A Green Laser And Fabry-Perot Cavity System For Jefferson Lab's Hall A Compton Polarimeter, Abdurahim Rakhman Dec 2011

The Design And Construction Of A Green Laser And Fabry-Perot Cavity System For Jefferson Lab's Hall A Compton Polarimeter, Abdurahim Rakhman

Physics - Dissertations

A high finesse Fabry-Perot cavity with a frequency doubled green laser (CW, 532 nm) have been built and installed in Hall A of Jefferson Lab for high precision Compton polarimetry project in spring of 2010. It provides a high intensity circularly polarized photon target for measuring the polarization of electron beam with energies from 1.0 GeV to 11.0 GeV in a nondestructive manner. The IR beam (CW, 1064 nm) from a Ytterbium doped fiber laser amplifier seeded by a Nd:YAG narrow linewidth NPRO laser is frequency doubled in by a single-pass Periodically Poled Lithium Niobate (PPMgLN) crystal. The maximum achieved …


Atlantic Multidecadal Oscillation-Forced Regional Summertime Precipitation Variations In The Central United States, Michael C. Veres Dec 2011

Atlantic Multidecadal Oscillation-Forced Regional Summertime Precipitation Variations In The Central United States, Michael C. Veres

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The purpose of this research is to identify the regional mechanisms by which the Atlantic Multidecadal Oscillation (AMO) influences summer (June-August) precipitation in the central U.S. This was accomplished by running two different sets of simulations using the Weather Research and Forecasting (WRF) regional climate model, one forced by observations and the other forced only by variations in the AMO as obtained via a global climate model (GCM). The results reveal a complex set of mechanisms active in the lower and middle troposphere by which the AMO influences summer circulation and precipitation in the central U.S. During the cold phase …


The Tetrafluoroborate Salt Of 4-Methoxybenzyl N-2-(Dimethylamino)Ethyl-N-Nitrosocarbamate: Synthesis, Crystal Structure And Dft Calculations, Helene Hedian, Vladimir Benin Dec 2011

The Tetrafluoroborate Salt Of 4-Methoxybenzyl N-2-(Dimethylamino)Ethyl-N-Nitrosocarbamate: Synthesis, Crystal Structure And Dft Calculations, Helene Hedian, Vladimir Benin

Chemistry Faculty Publications

The tetrafluoroborate salt of 4-methoxybenzyl N-2-(dimethylamino)ethyl-N-nitrosocarbamate was prepared in two steps, via the corresponding carbamate. Its crystal structure is monoclinic, space group P21/c. The unit cell dimensions are: a = 19.499(8) Å, b = 5.877(3) Å, c = 15.757(7) Å, α = 90°, β = 110.019(7)°, γ = 90°, V = 1696.5(12) Å3, Z = 4. The structure exhibits an unexpected, pseudo-gauche conformation with respect to the C2–C3 bond, due to a stabilizing hydrogen bond between the carbonyl oxygen (O1) and the hydrogen atom at the trialkylammonium center (H3n), with a distance between them of …


Approximation By Bernstein Polynomials At The Point Of Discontinuity, Jie Ling Liang Dec 2011

Approximation By Bernstein Polynomials At The Point Of Discontinuity, Jie Ling Liang

HIM 1990-2015

Chlodovsky showed that if x0 is a point of discontinuity of the first kind of the function f, then the Bernstein polynomials Bn(f, x0) converge to the average of the one-sided limits on the right and on the left of the function f at the point x0. In 2009, Telyakovskii in (5) extended the asymptotic formulas for the deviations of the Bernstein polynomials from the differentiable functions at the first-kind discontinuity points of the highest derivatives of even order and demonstrated the same result fails for the odd order case. Then in 2010, Tonkov in (6) found the right formulation …


Small-Scale Hybrid Alternative Energy Maximizer For Wind Turbines And Photovoltaic Panels, Ross Kerley Dec 2011

Small-Scale Hybrid Alternative Energy Maximizer For Wind Turbines And Photovoltaic Panels, Ross Kerley

HIM 1990-2015

This thesis describes the creation of a small-scale Hybrid Power System (HPS) that maximizes energy from a wind turbine and photovoltaic array. Small-scale HPS are becoming an increasingly viable energy solution as fossil fuel prices rise and more electricity is needed in remote areas. Modern HPS typically employ wind speed sensors and three power stages to extract maximum power. Modern systems also use passive rectifiers to convert AC from the wind turbine to DC that is usable by power electronics. This passive system inefficiently wastes power and introduces damaging harmonic noise to the wind turbine. The HPS described in this …


Report On Advances In The Field Of Artificial Intelligence Attributed To Captcha, Craig M. Schow Dec 2011

Report On Advances In The Field Of Artificial Intelligence Attributed To Captcha, Craig M. Schow

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A CAPTCHA is a specialized human interaction proof that exploits gaps between human and computer recognition abilities. By design, the hardness of a CAPTCHA is based on the difficulty of advancing the underlying artificial intelligence [AI] technology to a level that eliminates any exploitable gap. Due to this fact computer scientists have concluded that the widespread use of CAPTCHA would accelerate research in the underlying fields of AI eventually leading to near-­‐human capabilities in certain AI systems. Despite these predictions no attempt has been made to identify advances in AI which can be attributed to the use of CAPTCHA.

The …


Algebraic Properties Of Killing Vectors For Lorentz Metrics In Four Dimensions, Jesse W. Hicks Dec 2011

Algebraic Properties Of Killing Vectors For Lorentz Metrics In Four Dimensions, Jesse W. Hicks

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Four-dimensional space-times with symmetry play a central role in the theory of general relativity. In 1961, in the book Einstein Spaces, A.Z. Petrov gave a complete local classification of four-dimensional space-times based upon their local isometry group, that is, their Lie algebra of Killing vector fields. In this report we discuss algebraic and geometric properties of these Lie algebras. A database of these properties has been computed for the five-dimensional Lie algebras of Killing vectors found in Petrov. As an application of our work, we present dieomorphisms between a few pairs of these Lie algebras of Killing vectors.


Both The Journal And Handbook Of Research On Urban Mathematics Teaching And Learning, David W. Stinson Dec 2011

Both The Journal And Handbook Of Research On Urban Mathematics Teaching And Learning, David W. Stinson

Middle-Secondary Education and Instructional Technology Faculty Publications

In this editorial, the author explores the prestige that the edited "Handbook" has gained in the social sciences generally and in mathematical education specifically over the past few decades, and explores how this has established new power relationships and scholarly practices within urban mathematical education.


A Stochastic Version Of The Em Algorithm To Analyze Multivariate Skew-Normal Data With Missing Responses, M. Khounsiavash, M. Ganjali, T. Baghfalaki Dec 2011

A Stochastic Version Of The Em Algorithm To Analyze Multivariate Skew-Normal Data With Missing Responses, M. Khounsiavash, M. Ganjali, T. Baghfalaki

Applications and Applied Mathematics: An International Journal (AAM)

In this paper an algorithm called SEM, which is a stochastic version of the EM algorithm, is used to analyze multivariate skew-normal data with intermittent missing values. Also, a multivariate selection model framework for modeling of both missing and response mechanisms is formulated. By the SEM algorithm missing values of responses are inputed by the conditional distribution of missing values given observed data and then the log-likelihood of the pseudocomplete data is maximized. The algorithm is iterated until convergence of parameter estimates. Results of an application are also reported where a Bootstrap approach is used to compute the standard error …


Peristaltic Induced Flow Of A Two-Layered Suspension In Non-Uniform Channel, Amit Medhavi, Dharmendra Singh, Ajay S. Yadav, Ramesh S. Gautam Dec 2011

Peristaltic Induced Flow Of A Two-Layered Suspension In Non-Uniform Channel, Amit Medhavi, Dharmendra Singh, Ajay S. Yadav, Ramesh S. Gautam

Applications and Applied Mathematics: An International Journal (AAM)

Peristaltic transport of a two-layered particulate suspension in a non-uniform channel has been investigated. The coupled differential equations for both the fluid and the particle phases in the central as well as in the peripheral layers have been solved and the expression for the flow rate, the pressure rise and the friction force has been derived. The results obtained are discussed both qualitatively and quantitatively in brief. The significance of the particle concentration as well as the peripheral layer has been well explained.


The Power Series Solution Of Fingering Phenomenon Arising In Fluid Flow Through Homogeneous Porous Media, Kinjal Patel, M. N. Mehta, Twinkle R. Patel Dec 2011

The Power Series Solution Of Fingering Phenomenon Arising In Fluid Flow Through Homogeneous Porous Media, Kinjal Patel, M. N. Mehta, Twinkle R. Patel

Applications and Applied Mathematics: An International Journal (AAM)

The present paper deals with the approximate solution of the fingering phenomenon occurring when water is pushed into oil in homogeneous porous media with capillary mean pressure. The phenomenon is formulated mathematically as a water-oil double phase flow problem. The solution of the nonlinear partial differential equation of fingering phenomenon has been discussed in terms of the power series using appropriate boundary conditions for any timeT>0 . The solution is in ascending power series which represents saturation of injected fluid in fingering phenomenon & its graphical and numerical presentation is given in MATLAB coding.


A Group Acceptance Sampling Plans For Lifetimes Following A Marshall-Olkin Extended Exponential Distribution, G. S. Rao Dec 2011

A Group Acceptance Sampling Plans For Lifetimes Following A Marshall-Olkin Extended Exponential Distribution, G. S. Rao

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, a group acceptance sampling plan is developed for a truncated life test when the lifetime of an item follows the Marshall-Olkin extended exponential distribution. The minimum number of groups required for a given group size and the acceptance number is determined when the consumer’s risk and the test termination time are specified. The operating characteristic values, according to various quality levels, are found and the minimum ratios of the true average life to the specified life at the specified producer’s risk are obtained. The results are explained with examples.