La physique des réacteurs nucléaires est le premier ouvrage français conçu pour aborder de façon progressive et détaillée la complexité théorique du comportement des neutrons, en situation sûre ou accidentelle. Fruit de l’expérience pédagogique de l’auteur et de son expertise internationale reconnue en sûreté nucléaire, il est rapidement devenu un ouvrage de référence au sein de la communauté nucléaire française. Après des rappels de physique nucléaire replaçant les notions théoriques dans leur contexte historique, l’auteur expose les théories mathématico-physiques les plus récentes concernant : • le ralentissement des neutrons dans la matière ; • les particules chargées et les rayonnements électromagnétiques ; • les phases de calcul, en soulignant les hypothèses simplificatrices ; • le concept de criticité, lorsque se développe et s’entretient une réaction nucléaire en chaîne ; • le calcul théorique des réacteurs homogènes et hétérogènes ; • les problèmes d’autoprotection ; • les méthodes numériques des 2 approches historiques du traitement des neutrons (transport neutronique et diffusion). Cette 2e édition, revue et augmentée, approfondit certaines notions, notamment le spectre théorique de fission, l’effet des liaisons cristallines, l’effet de l’hétérogénéité du champ de température, l’effet Dancoff, les équations du transport en géométrie dimensionnelle, le calcul du facteur anti-trappe, la méthode des neutrons pulsés, l’effet d’ombre de l’intégrale de résonance, la méthode Feynman-a, le traitement des instrumentations de l’EPR… Complété par plus de 400 références bibliographiques, dont de nombreuses commentées et une annexe replaçant les travaux d’EDF dans le contexte national du développement de l’énergie nucléaire, cet ensemble constitue la référence théorique la plus complète en neutronique. Cet ouvrage est conforme aux enseignements de l’Institut de transfert de technologie d’EDF et sert de référentiel aux enseignements de l’École nationale supérieure d’ingénieurs de Bourges (INSA-Centre Val de Loire). Il a été conçu pour les ingénieurs et techniciens sur sites souhaitant enrichir leur propre expertise, pour les étudiants de 3e cycle et les élèves ingénieurs en sciences énergétiques.

This introduction to the theory of Sobolev spaces and Hilbert space methods in partial differential equations is geared toward readers of modest mathematical backgrounds. It offers coherent, accessible demonstrations of the use of these techniques in developing the foundations of the theory of finite element approximations. J. T. Oden is Director of the Institute for Computational Engineering & Sciences (ICES) at the University of Texas at Austin, and J. N. Reddy is a Professor of Engineering at Texas A&M University. They developed this essentially self-contained text from their seminars and courses for students with diverse educational backgrounds. Their effective presentation begins with introductory accounts of the theory of distributions, Sobolev spaces, intermediate spaces and duality, the theory of elliptic equations, and variational boundary value problems. The second half of the text explores the theory of finite element interpolation, finite element methods for elliptic equations, and finite element methods for initial boundary value problems. Detailed proofs of the major theorems appear throughout the text, in addition to numerous examples.

Topics in Numerical Analysis II contains in complete form, the papers given by the invited speakers to the Conference on Numerical Analysis held under the auspices of the National Committee for Mathematics of the Royal Irish Academy at University College, Dublin from 29th July to 2nd August, 1974. In addition, the titles of the contributed papers are listed together with the names and addresses of the authors who presented them at the conference. This book is divided into 20 chapters that present the papers in their entirety. They discuss such topics as applications of approximation theory to numerical analysis; interior regularity and local convergence of Galerkin finite element approximations for elliptic equations; and numerical estimates for the error of Gauss-Jacobi quadrature formulae. Some remarks on the unified treatment of elementary functions by microprogramming; application of finite difference methods to exploration seismology; and variable coefficient multistep methods for ordinary differential equations applied to parabolic partial differential equations are also presented. Other chapters cover realistic estimates for generic constants in multivariate pointwise approximation; matching of essential boundary conditions in the finite element method; and collocation, difference equations, and stitched function representations. This book will be of interest to practitioners in the fields of mathematics and computer science.

When Herb Keller suggested, more than two years ago, that we update our lectures held at the Tata Institute of Fundamental Research in 1977, and then have it published in the collection Springer Series in Computational Physics, we thought, at first, that it would be an easy task. Actually, we realized very quickly that it would be more complicated than what it seemed at first glance, for several reasons: 1. The first version of Numerical Methods for Nonlinear Variational Problems was, in fact, part of a set of monographs on numerical mat- matics published, in a short span of time, by the Tata Institute of Fun- mental Research in its well-known series Lectures on Mathematics and Physics; as might be expected, the first version systematically used the material of the above monographs, this being particularly true for Lectures on the Finite Element Method by P. G. Ciarlet and Lectures on Optimization—Theory and Algorithms by J. Cea. This second version had to be more self-contained. This necessity led to some minor additions in Chapters I-IV of the original version, and to the introduction of a chapter (namely, Chapter Y of this book) on relaxation methods, since these methods play an important role in various parts of this book.

This text presenting the mathematical theory of finite elements is organized into three main sections. The first part develops the theoretical basis for the finite element methods, emphasizing inf-sup conditions over the more conventional Lax-Milgrim paradigm. The second and third parts address various applications and practical implementations of the method, respectively. It contains numerous examples and exercises.

Undoubtedly, the Navier-Stokes equations are of basic importance within the context of modern theory of partial differential equations. Although the range of their applicability to concrete problems has now been clearly recognised to be limited, as my dear friend and bright colleague K.R. Ra jagopal has showed me by several examples during the past six years, the mathematical questions that remain open are of such a fascinating and challenging nature that analysts and applied mathematicians cannot help being attracted by them and trying to contribute to their resolution. Thus, it is not a coincidence that over the past ten years more than seventy sig nificant research papers have appeared concerning the well-posedness of boundary and initial-boundary value problems. In this monograph I shall perform a systematic and up-to-date investiga tion of the fundamental properties of the Navier-Stokes equations, including existence, uniqueness, and regularity of solutions and, whenever the region of flow is unbounded, of their spatial asymptotic behavior. I shall omit other relevant topics like boundary layer theory, stability, bifurcation, de tailed analysis of the behavior for large times, and free-boundary problems, which are to be considered "advanced" ones. In this sense the present work should be regarded as "introductory" to the matter.