Méthodes multiniveau algébriques pour les éléments d'arête PDF Download

Author: Ronan Perrussel
Publisher:
ISBN:
Category :
Languages : fr
Pages : 119

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Book Description
Le calcul numérique du champ électrique ou magnétique intervient aussi bien dans la mise au point d'outils de communication performants que dans les problèmes de compatibilité électromagnétique des systèmes électriques ou de modélisation de l'interaction champ-vivant. Ce calcul est fréquemment fondé sur la discrétisation des équations de Maxwell par la méthode des éléments finis d'arête. Il conduit alors à la résolution d'un système linéaire creux mais généralement de grande taille. L'objectif de ce travail est de proposer une méthode multiniveau algébrique pour la résolution des systèmes linéaires issus d'une discrétisation par la méthode des éléments finis d'arête. En effet, les méthodes itératives multiniveau construisent des algorithmes qui s'avèrent être les plus performants pour certaines classes d'équations aux dérivées partielles. Ces méthodes s'appuient, dans leur version géométrique, sur une hiérarchie de maillages emboîtés. Cependant pour des applications réalistes cette hiérarchie ne peut pas toujours être construite et il faut définir algébriquement les différents niveaux. La stratégie algébrique de définition des niveaux grossiers que nous proposons repose sur la construction de fonctions grossières nodales et d'arête vérifiant une contrainte de compatibilité. En outre, les fonctions grossières d'arête doivent minimiser une fonctionnelle d'énergie. Ce problème de minimisation avec contrainte est résolu par deux techniques : l'une utilise les multiplicateurs de Lagrange, l'autre s'appuie sur la résolution d'une suite de problèmes de flot dans un graphe. Des expériences numériques illustrent les performances de différentes versions de notre méthode.

Author:
Publisher: Lulu.com
ISBN: 1430318678
Category : Reference
Languages : en
Pages : 385

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Book Description
This volume presents a catalogue of over 2000 doctoral theses by Africans in all fields of mathematics, including applied mathematics, mathematics education and history of mathematics. The introduction contains information about distribution by country, institutions, period, and by gender, about mathematical density, and mobility of mathematicians. Several appendices are included (female doctorate holders, doctorates in mathematics education, doctorates awarded by African universities to non-Africans, doctoral theses by non-Africans about mathematics in Africa, activities of African mathematicians at the service of their communities). Paulus Gerdes compiled the information in his capacity of Chairman of the African Mathematical Union Commission for the History of Mathematics in Africa (AMUCHMA). The book contains a preface by Mohamed Hassan, President of the African Academy of Sciences (AAS) and Executive Director of the Academy of Sciences for the Developing World (TWAS). (383 pp.)

Author: Youping Chen
Publisher: Springer Science & Business Media
ISBN: 0387333681
Category : Science
Languages : en
Pages : 211

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Book Description
This book covers the fundamentals of continuum mechanics, the integral formulation methods of continuum problems, the basic concepts of finite element methods, and the methodologies, formulations, procedures, and applications of various meshless methods. It also provides general and detailed procedures of meshless analysis on elastostatics, elastodynamics, non-local continuum mechanics and plasticity with a large number of numerical examples. Some basic and important mathematical methods are included in the Appendixes. For readers who want to gain knowledge through hands-on experience, the meshless programs for elastostatics and elastodynamics are provided on an included disc.

Author: Walter D. Pilkey
Publisher: John Wiley & Sons
ISBN: 1119532523
Category : Technology & Engineering
Languages : en
Pages : 816

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Book Description
The bible of stress concentration factors—updated to reflect today's advances in stress analysis This book establishes and maintains a system of data classification for all the applications of stress and strain analysis, and expedites their synthesis into CAD applications. Filled with all of the latest developments in stress and strain analysis, this Fourth Edition presents stress concentration factors both graphically and with formulas, and the illustrated index allows readers to identify structures and shapes of interest based on the geometry and loading of the location of a stress concentration factor. Peterson's Stress Concentration Factors, Fourth Edition includes a thorough introduction of the theory and methods for static and fatigue design, quantification of stress and strain, research on stress concentration factors for weld joints and composite materials, and a new introduction to the systematic stress analysis approach using Finite Element Analysis (FEA). From notches and grooves to shoulder fillets and holes, readers will learn everything they need to know about stress concentration in one single volume. Peterson's is the practitioner's go-to stress concentration factors reference Includes completely revised introductory chapters on fundamentals of stress analysis; miscellaneous design elements; finite element analysis (FEA) for stress analysis Features new research on stress concentration factors related to weld joints and composite materials Takes a deep dive into the theory and methods for material characterization, quantification and analysis methods of stress and strain, and static and fatigue design Peterson's Stress Concentration Factors is an excellent book for all mechanical, civil, and structural engineers, and for all engineering students and researchers.

Author: Barna Szabó
Publisher: John Wiley & Sons
ISBN: 9780471502739
Category : Technology & Engineering
Languages : en
Pages : 408

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Book Description
Covers the fundamentals of linear theory of finite elements, from both mathematical and physical points of view. Major focus is on error estimation and adaptive methods used to increase the reliability of results. Incorporates recent advances not covered by other books.

Author: Donald A. Drew
Publisher: Springer Science & Business Media
ISBN: 1468471090
Category : Mathematics
Languages : en
Pages : 155

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Book Description
This IMA Volume in Mathematics and its Applications PARTICULATE FLOWS: PROCESSING AND RHEOLOGY is based on the proceedings of a very successful one-week workshop with the same title, which was an integral part of the 1995-1996 IMA program on "Mathematical Methods in Materials Science." We would like to thank Donald A. Drew, Daniel D. Joseph, and Stephen L. Passman for their excellent work as organizers of the meeting. We also take this opportunity to thank the National Science Foun dation (NSF), the Army Research Office (ARO) and the Office of Naval Research (ONR), whose financial support made the workshop possible. A vner Friedman Robert Gulliver v PREFACE The workshop on Particulate Flows: Processing and Rheology was held January 8-12, 1996 at the Institute for Mathematics and its Applications on the University of Minnesota Twin Cities campus as part of the 1995- 96 Program on Mathematical Methods in Materials Science. There were about forty participants, and some lively discussions, in spite of the fact that bad weather on the east coast kept some participants from attending, and caused scheduling changes throughout the workshop. Heterogeneous materials can behave strangely, even in simple flow sit uations. For example, a mixture of solid particles in a liquid can exhibit behavior that seems solid-like or fluid-like, and attempting to measure the "viscosity" of such a mixture leads to contradictions and "unrepeatable" experiments. Even so, such materials are commonly used in manufacturing and processing.

Author: Eric Jerome Dickey
Publisher: Penguin
ISBN: 0451201027
Category : Fiction
Languages : en
Pages : 418

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Book Description
Hailed as one of “the most successful Black authors of the last quarter-century” (The New York Times), Eric Jerome Dickey captures the humor and heartache of modern love in this sexy, soulful tale. Attraction can be instant. So can the consequences. Just ask Leonard, Debra, Tyrel, and Shelby. Four friends with so much in common: They’re good-hearted, loyal, and vulnerable to the complicated state of relations between men and women. They’re all searching for love—or at least unqualified affection. Either way, their lives are about to change…. A witty, honest portrait of the choices we make in the search for happy ever after, Friends and Lovers chronicles the lives of four young Black people through the joy, laughter, and pain of not-so-everyday life.

Author: Mats G. Larson
Publisher: Springer Science & Business Media
ISBN: 3642332870
Category : Computers
Languages : en
Pages : 403

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Book Description
This book gives an introduction to the finite element method as a general computational method for solving partial differential equations approximately. Our approach is mathematical in nature with a strong focus on the underlying mathematical principles, such as approximation properties of piecewise polynomial spaces, and variational formulations of partial differential equations, but with a minimum level of advanced mathematical machinery from functional analysis and partial differential equations. In principle, the material should be accessible to students with only knowledge of calculus of several variables, basic partial differential equations, and linear algebra, as the necessary concepts from more advanced analysis are introduced when needed. Throughout the text we emphasize implementation of the involved algorithms, and have therefore mixed mathematical theory with concrete computer code using the numerical software MATLAB is and its PDE-Toolbox. We have also had the ambition to cover some of the most important applications of finite elements and the basic finite element methods developed for those applications, including diffusion and transport phenomena, solid and fluid mechanics, and also electromagnetics.​