1,507,774 research outputs found

    Numerical Methods of Multifractal Analysis in Information Communication Systems and Networks

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    In this chapter, the main principles of the theory of fractals and multifractals are stated. A singularity spectrum is introduced for the random telecommunication traffic, concepts of fractal dimensions and scaling functions, and methods used in their determination by means of Wavelet Transform Modulus Maxima (WTMM) are proposed. Algorithm development methods for estimating multifractal spectrum are presented. A method based on multifractal data analysis at network layer level by means of WTMM is proposed for the detection of traffic anomalies in computer and telecommunication networks. The chapter also introduces WTMM as the informative indicator to exploit the distinction of fractal dimen- sions on various parts of a given dataset. A novel approach based on the use of multifractal spectrum parameters is proposed for estimating queuing performance for the generalized multifractal traffic on the input of a buffering device. It is shown that the multifractal character of traffic has significant impact on queuing performance characteristics

    Fractional boundary value problems: Analysis and numerical methods

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    This is the author's PDF of an article published in Fractional calculus and applied analysis 2011. The original publication is available at www.springerlink.comThis journal article discusses nonlinear boundary value problems.Fundacao para a Ciencia e Tecnologi

    Fractional boundary value problems: Analysis and numerical methods

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    This is the author's PDF of an article published in Fractional calculus and applied analysis 2011. The original publication is available at www.springerlink.comThis journal article discusses nonlinear boundary value problems.Fundacao para a Ciencia e Tecnologi

    Combined creep and plastic analysis with numerical methods

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    The combination of plastic and creep analysis formulation are developed in this paper. The boundary element method and the finite element method are applied in plates in order to do the numerical analysis. This new approach is developed to combine the constitutive equation for time hardening creep and the constitutive equation for plasticity, which is based on the von Mises criterion and the Prandtl-Reuss flow. The implementation of creep strain in the formulation is achieved through domain integrals. The creep phenomenon takes place in the domain which is discretized into quadratic quadrilateral continuous and discontinuous cells. The creep analysis is applied to metals with a power law creep for the secondary creep stage. Results obtained for three models studied are compared to those published in the literature. The obtained results are in good agreement and evinced that the Boundary Element Method could be a suitable tool to deal with combined nonlinear problems

    Finite element methods for surface PDEs

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    In this article we consider finite element methods for approximating the solution of partial differential equations on surfaces. We focus on surface finite elements on triangulated surfaces, implicit surface methods using level set descriptions of the surface, unfitted finite element methods and diffuse interface methods. In order to formulate the methods we present the necessary geometric analysis and, in the context of evolving surfaces, the necessary transport formulae. A wide variety of equations and applications are covered. Some ideas of the numerical analysis are presented along with illustrative numerical examples

    VI Workshop on Computational Data Analysis and Numerical Methods: Book of Abstracts

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    The VI Workshop on Computational Data Analysis and Numerical Methods (WCDANM) is going to be held on June 27-29, 2019, in the Department of Mathematics of the University of Beira Interior (UBI), Covilhã, Portugal and it is a unique opportunity to disseminate scientific research related to the areas of Mathematics in general, with particular relevance to the areas of Computational Data Analysis and Numerical Methods in theoretical and/or practical field, using new techniques, giving especial emphasis to applications in Medicine, Biology, Biotechnology, Engineering, Industry, Environmental Sciences, Finance, Insurance, Management and Administration. The meeting will provide a forum for discussion and debate of ideas with interest to the scientific community in general. With this meeting new scientific collaborations among colleagues, namely new collaborations in Masters and PhD projects are expected. The event is open to the entire scientific community (with or without communication/poster)

    Numerical integration methods and error analysis

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    Numerická integrace je důležitá pro výpočet integrálů, které neumíme spočítat, ale můžeme nahradit integrovanou funkci jednodušší. V této práci nahrazujeme integrál konstantní, lineární a kvadratickou funkcí. Cílem práce je zvládnutí základních numerických metod výpočtu určitého integrálu funkce jedné reálné proměnné. Dále jsou odvozeny vzorce pro odhady chyb včetně jejich porovnání. Výsledkem této práce je porovnání chyb základních integračních numerických metod.Numerical integration is important for solving integrals that we can not calculate but we can replace integrated with simpler functions. In this thesis, we replace the integral with a constant, linear and quadratic function. The goal of the thesis is achieve the basis numerical methods of calculating a definite integral of the function of one real variable. Next step is inference formulas for error estimates including their comparison. The results of this thesis is the comparison of errors of basic integration numerical methods.470 - Katedra aplikované matematikyvelmi dobř
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