Estimating the Error of Numerical Solutions of Systems of Reaction-Diffusion Equations

Estimating the Error of Numerical Solutions of Systems of Reaction-Diffusion Equations PDF Author: Donald J. Estep
Publisher: American Mathematical Soc.
ISBN: 0821820729
Category : Mathematics
Languages : en
Pages : 125

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Book Description
This paper is concerned with the computational estimation of the error of numerical solutions of potentially degenerate reaction-diffusion equations. The underlying motivation is a desire to compute accurate estimates as opposed to deriving inaccurate analytic upper bounds. In this paper, we outline, analyze, and test an approach to obtain computational error estimates based on the introduction of the residual error of the numerical solution and in which the effects of the accumulation of errors are estimated computationally. We begin by deriving an a posteriori relationship between the error of a numerical solution and its residual error using a variational argument. This leads to the introduction of stability factors, which measure the sensitivity of solutions to various kinds of perturbations. Next, we perform some general analysis on the residual errors and stability factors to determine when they are defined and to bound their size. Then we describe the practical use of the theory to estimate the errors of numerical solutions computationally. Several key issues arise in the implementation that remain unresolved and we present partial results and numerical experiments about these points. We use this approach to estimate the error of numerical solutions of nine standard reaction-diffusion models and make a systematic comparison of the time scale over which accurate numerical solutions can be computed for these problems. We also perform a numerical test of the accuracy and reliability of the computational error estimate using the bistable equation. Finally, we apply the general theory to the class of problems that admit invariant regions for the solutions, which includes seven of the main examples. Under this additional stability assumption, we obtain a convergence result in the form of an upper bound on the error from the a posteriori error estimate. We conclude by discussing the preservation of invariant regions under discretization.

Estimating the Error of Numerical Solutions of Systems of Reaction-Diffusion Equations

Estimating the Error of Numerical Solutions of Systems of Reaction-Diffusion Equations PDF Author: Donald J. Estep
Publisher: American Mathematical Soc.
ISBN: 0821820729
Category : Mathematics
Languages : en
Pages : 125

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Book Description
This paper is concerned with the computational estimation of the error of numerical solutions of potentially degenerate reaction-diffusion equations. The underlying motivation is a desire to compute accurate estimates as opposed to deriving inaccurate analytic upper bounds. In this paper, we outline, analyze, and test an approach to obtain computational error estimates based on the introduction of the residual error of the numerical solution and in which the effects of the accumulation of errors are estimated computationally. We begin by deriving an a posteriori relationship between the error of a numerical solution and its residual error using a variational argument. This leads to the introduction of stability factors, which measure the sensitivity of solutions to various kinds of perturbations. Next, we perform some general analysis on the residual errors and stability factors to determine when they are defined and to bound their size. Then we describe the practical use of the theory to estimate the errors of numerical solutions computationally. Several key issues arise in the implementation that remain unresolved and we present partial results and numerical experiments about these points. We use this approach to estimate the error of numerical solutions of nine standard reaction-diffusion models and make a systematic comparison of the time scale over which accurate numerical solutions can be computed for these problems. We also perform a numerical test of the accuracy and reliability of the computational error estimate using the bistable equation. Finally, we apply the general theory to the class of problems that admit invariant regions for the solutions, which includes seven of the main examples. Under this additional stability assumption, we obtain a convergence result in the form of an upper bound on the error from the a posteriori error estimate. We conclude by discussing the preservation of invariant regions under discretization.

Error Estimation and Adaptive Discretization Methods in Computational Fluid Dynamics

Error Estimation and Adaptive Discretization Methods in Computational Fluid Dynamics PDF Author: Timothy J. Barth
Publisher: Springer Science & Business Media
ISBN: 3662051893
Category : Mathematics
Languages : en
Pages : 354

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Book Description
As computational fluid dynamics (CFD) is applied to ever more demanding fluid flow problems, the ability to compute numerical fluid flow solutions to a user specified tolerance as well as the ability to quantify the accuracy of an existing numerical solution are seen as essential ingredients in robust numerical simulation. Although the task of accurate error estimation for the nonlinear equations of CFD seems a daunting problem, considerable effort has centered on this challenge in recent years with notable progress being made by the use of advanced error estimation techniques and adaptive discretization methods. To address this important topic, a special course wasjointly organized by the NATO Research and Technology Office (RTO), the von Karman Insti tute for Fluid Dynamics, and the NASA Ames Research Center. The NATO RTO sponsored course entitled "Error Estimation and Solution Adaptive Discretization in CFD" was held September 10-14, 2002 at the NASA Ames Research Center and October 15-19, 2002 at the von Karman Institute in Belgium. During the special course, a series of comprehensive lectures by leading experts discussed recent advances and technical progress in the area of numerical error estimation and adaptive discretization methods with spe cific emphasis on computational fluid dynamics. The lecture notes provided in this volume are derived from the special course material. The volume con sists of 6 articles prepared by the special course lecturers.

Numerical Solution of Time-Dependent Advection-Diffusion-Reaction Equations

Numerical Solution of Time-Dependent Advection-Diffusion-Reaction Equations PDF Author: Willem Hundsdorfer
Publisher: Springer Science & Business Media
ISBN: 3662090171
Category : Technology & Engineering
Languages : en
Pages : 479

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Book Description
Unique book on Reaction-Advection-Diffusion problems

SIAM Journal on Scientific Computing

SIAM Journal on Scientific Computing PDF Author:
Publisher:
ISBN:
Category : Mathematical statistics
Languages : en
Pages : 920

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Book Description


Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 376

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Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Cellular Automata

Cellular Automata PDF Author: Hiroshi Umeo
Publisher: Springer
ISBN: 3540799923
Category : Computers
Languages : en
Pages : 593

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Book Description
This book constitutes the refereed proceedings of the 8th International Conference on Cellular Automata for Research and Industry, ACRI 2008, held in Yokohama, Japan, in September 2008. The 43 revised full papers and 22 revised poster papers presented together with 4 invited lectures were carefully reviewed and selected from 78 submissions. The papers focus on challenging problems and new research not only in theoretical but application aspects of cellular automata, including cellular automata tools and computational sciences. The volume also contains 11 extended abstracts dealing with crowds and cellular automata, which were presented during the workshop C&CA 2008. The papers are organized in topical sections on CA theory and implementation, computational theory, physical modeling, urban, environmental and social modeling, pedestrian and traffic flow modeling, crypto and security, system biology, CA-based hardware, as well as crowds and cellular automata.

Adaptive Multilevel Solution of Nonlinear Parabolic PDE Systems

Adaptive Multilevel Solution of Nonlinear Parabolic PDE Systems PDF Author: Jens Lang
Publisher: Springer Science & Business Media
ISBN: 3662044846
Category : Computers
Languages : en
Pages : 161

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Book Description
Nowadays there is an increasing emphasis on all aspects of adaptively gener ating a grid that evolves with the solution of a PDE. Another challenge is to develop efficient higher-order one-step integration methods which can handle very stiff equations and which allow us to accommodate a spatial grid in each time step without any specific difficulties. In this monograph a combination of both error-controlled grid refinement and one-step methods of Rosenbrock-type is presented. It is my intention to impart the beauty and complexity found in the theoretical investigation of the adaptive algorithm proposed here, in its realization and in solving non-trivial complex problems. I hope that this method will find many more interesting applications. Berlin-Dahlem, May 2000 Jens Lang Acknowledgements I have looked forward to writing this section since it is a pleasure for me to thank all friends who made this work possible and provided valuable input. I would like to express my gratitude to Peter Deuflhard for giving me the oppor tunity to work in the field of Scientific Computing. I have benefited immensly from his help to get the right perspectives, and from his continuous encourage ment and support over several years. He certainly will forgive me the use of Rosenbrock methods rather than extrapolation methods to integrate in time.

Trends in Nonlinear Analysis

Trends in Nonlinear Analysis PDF Author: Markus Kirkilionis
Publisher: Springer Science & Business Media
ISBN: 9783540441984
Category : Mathematics
Languages : en
Pages : 446

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Book Description
Applied mathematics is a central connecting link between scientific observations and their theoretical interpretation. Nonlinear analysis has surely contributed major developments which nowadays shape the face of applied mathematics. At the beginning of the millennium, all sciences are expanding at increased speed. Technological, ecological, economical and medical problem solving is a central issue of every modern society. Mathematical models help to expose fundamental structures hidden in these problems and serve as unifying tools to deepen our understanding. What are the new challenges applied mathematics has to face with the increased diversity of scientific problems? In which direction should the classical tools of nonlinear analysis be developed further? How do new available technologies influence the development of the field? How can problems be solved which have been beyond reach in former times? It is the aim of this book to explore new developments in the field by way of discussion of selected topics from nonlinear analysis.

Numerical Mathematics and Advanced Applications 2009

Numerical Mathematics and Advanced Applications 2009 PDF Author: Gunilla Kreiss
Publisher: Springer Science & Business Media
ISBN: 3642117953
Category : Mathematics
Languages : en
Pages : 900

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Book Description
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Splitting Methods in Communication, Imaging, Science, and Engineering

Splitting Methods in Communication, Imaging, Science, and Engineering PDF Author: Roland Glowinski
Publisher: Springer
ISBN: 3319415891
Category : Mathematics
Languages : en
Pages : 822

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Book Description
This book is about computational methods based on operator splitting. It consists of twenty-three chapters written by recognized splitting method contributors and practitioners, and covers a vast spectrum of topics and application areas, including computational mechanics, computational physics, image processing, wireless communication, nonlinear optics, and finance. Therefore, the book presents very versatile aspects of splitting methods and their applications, motivating the cross-fertilization of ideas.