Download or read book R solution exacte d un probl me d optimisation combinatoire NP difficile sur grilles de calcul written by Abdelaziz Djerrah and published by . This book was released on 2006 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ces dernières années, de nombreuses avancées dans la résolution exacte de problèmes d'optimisation difficiles ont été enregistrées. Le premier facteur de ces succès est le développement de nouvelles techniques de calcul de bornes inférieures pour ces problèmes et le deuxième facteur est sans aucun doute la progression de la puissance de calcul des machines parallèles en utilisant des grilles de calcul.Le QAP est l'un des problèmes d'Optimisation Combinatoire les plus difficiles.Bien qu'il soit ancien, ce problème suscite encore aujourd'hui beaucoup d'intérêt. A cela, deux raison principales: d'une part, beaucoup de problèmes du monde industriel sont modélisés par cette application; d'autre part, de nombreux autres problèmes d'Optimisation Combinatoire, comme le problème du voyageur de commerce (TSP), ou encore des problèmes de la théorie de graphe tel le problème de clique maximal et problème de partitionnement de graphe s'expriment comme des cas particuliers du QAP.Le travail présenté dans ce mémoire porte sur l'étude de la parallélisation de la méthode Branch-and-Bound. Le modèle de parallélisation est implémenté dans la librairie d'aide à la programmation Bob++ et un algorithme Branch-and-Bound parallèle est proposée pour le QAP. L'algorithme, basé sur une nouvelle technique de cacul de borne inférieur, est développé pour s'exécuter, avec un minimum de changements, sur une large gamme de machines séquentielles et/ou parallèles y compris les larges systèmes distribués comme les grilles de calcul. Les résultats obtenus montrent l'efficacité et extensibilité de l'algorithme
Download or read book Approximation de probl mes de couverture et de partitionnement de graphes written by Laurent Alfandari and published by . This book was released on 1999 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: PARMI LES PROBLEMES D'OPTIMISATION, LES PROBLEMES NP-DIFFICILES SONT TELS QUE LES SEULES METHODES CONNUES DE RESOLUTION EXACTE SONT DES ALGORITHMES DE COMPLEXITE EXPONENTIELLE, INDUISANT DES TEMPS DE CALCUL SOUVENT PROHIBITIFS POUR DES PROBLEMES DE TRES GRANDE TAILLE. LA THEORIE DE L'APPROXIMATION POLYNOMIALE, QUI EST LE CADRE D'ETUDE DE CETTE THESE, CHERCHE A CONCEVOIR POUR CES PROBLEMES DES ALGORITHMES APPROCHES, DE COMPLEXITE POLYNOMIALE, AVEC GARANTIE DE PERFORMANCE, I.E. FOURNISSANT UNE SOLUTION NON TOUJOURS OPTIMALE MAIS DONT ON SOUHAITE POUVOIR BORNER A PRIORI LA VALEUR RELATIVEMENT A L'OPTIMUM. NOUS TRAITONS PARTICULIEREMENT DES PROBLEMES D'OPTIMISATION COMBINATOIRE DANS DES GRAPHES, CONSISTANT A COUVRIR OU PARTITIONNER LES SOMMETS OU LES ARETES D'UN GRAPHE PAR DES SOUS-GRAPHES. NOUS DEFINISSONS AINSI LA CLASSE MST DES PROBLEMES MAITRE-ESCLAVE APPROXIMABLES, DONT NOUS MONTRONS QU'ILS SE REDUISENT AU PROBLEME CLASSIQUE DE SET COVERING PAR UNE NOUVELLE FORME DE REDUCTION PRESERVANT L'APPROXIMATION APPELEE PSEUDO-REDUCTION. NOUS EN DEDUISONS L'INCLUSION DE LA CLASSE MST DANS LA CLASSE APX LOGN DES PROBLEMES APPROXIMABLES A RAPPORT LOGARITHMIQUE. NOUS ETENDONS L'UTILISATION DE CETTE APPROCHE ET DE NOTRE PSEUDO-REDUCTION A L'APPROXIMATION DE PROBLEMES DE PACKING DE GRAPHES. NOUS MONTRONS QUE L'APPROCHE MAITRE-ESCLAVE S'APPLIQUE A DE NOMBREUX PROBLEMES D'OPTIMISATION, TELS QUE LE PROBLEME DE LA FORET RECOUVRANTE MINIMUM DE DIAMETRE BORNE, UN PROBLEME DE COUVERTURE DES ARETES PAR DES ARBRES, CERTAINES RESTRICTIONS DU PROBLEME DE CONSTRUCTION DE ROTATIONS, AINSI QUE LE PROBLEME DE L'ARBRE RECOUVRANT DE POIDS MINIMUM DE PROFONDEUR 2, POUR LEQUEL NOUS FOURNISSONS DIVERS RESULTATS D'APPROXIMATION DEPASSANT LE CADRE DE LA CLASSE MST. FINALEMENT, NOUS NOUS INTERESSONS A LA FORMULATION LOGIQUE DES PROBLEMES DE COUVERTURE ET DE PARTITIONNEMENT DANS LE CADRE DE L'APPROXIMATION POLYNOMIALE, ET CONCLUONS SUR UNE NOUVELLE HIERARCHIE DE CLASSES A L'INTERIEUR DE LA CLASSE APX LOGN.
Download or read book Une approche efficace pour le passage sur grilles de calcul de m thodes d optimisation combinatoire written by Mohand Mezmaz and published by . This book was released on 2007 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: La résolution exacte de problèmes d'optimisation combinatoire de grande taille constitue un défi pour les grilles. En effet, il est nécessaire de repenser les algorithmes de résolution pour prendre en compte les caractéristiques de tels environnements. notamment leur grande échelle. l'hétérogénéité et la disponibilité dynamique de leurs ressources. et leur nature multi-domaine d'administration. Dans cette thèse, nous avons proposé une nouvelle approche de passage sur grilles des méthodes exactes de type Branch-and-Bound appelée B&B@Grid. Cette approche est basée sur un codage des unités de travail sous forme d'intervalles permettant de minimiser le coût des communications induites par les opérations de régulation de charge, de tolérance aux pannes et de détection de la terminaison. Cette approche. environ 100 fois plus performante en terme de coût de communication que la meilleure approche connue. a permis la résolution optimale sur la grille nationale Grid5000 d'une instance standard du problème du Flow-Shop restée non résolue depuis une quinzaine d'années. Pour accélérer la résolution. nous avons également étudié la coopération sur la grille de la méthode exacte avec une méta-heuristique parallèle hybride. Deux modes de coopération ont été considérés : le mode relais où la méta-heuristique est exécutée avant la méthode exacte, le mode co-évolutionnaire où les deux méthodes sont exécutées en parallèle. La mise en oeuvre d'une telle coopération sur la grille nous a amené il proposer une extension du modèle de coopération Linda.
Download or read book Using OpenMP written by Barbara Chapman and published by MIT Press. This book was released on 2007-10-12 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive overview of OpenMP, the standard application programming interface for shared memory parallel computing—a reference for students and professionals. "I hope that readers will learn to use the full expressibility and power of OpenMP. This book should provide an excellent introduction to beginners, and the performance section should help those with some experience who want to push OpenMP to its limits." —from the foreword by David J. Kuck, Intel Fellow, Software and Solutions Group, and Director, Parallel and Distributed Solutions, Intel Corporation OpenMP, a portable programming interface for shared memory parallel computers, was adopted as an informal standard in 1997 by computer scientists who wanted a unified model on which to base programs for shared memory systems. OpenMP is now used by many software developers; it offers significant advantages over both hand-threading and MPI. Using OpenMP offers a comprehensive introduction to parallel programming concepts and a detailed overview of OpenMP. Using OpenMP discusses hardware developments, describes where OpenMP is applicable, and compares OpenMP to other programming interfaces for shared and distributed memory parallel architectures. It introduces the individual features of OpenMP, provides many source code examples that demonstrate the use and functionality of the language constructs, and offers tips on writing an efficient OpenMP program. It describes how to use OpenMP in full-scale applications to achieve high performance on large-scale architectures, discussing several case studies in detail, and offers in-depth troubleshooting advice. It explains how OpenMP is translated into explicitly multithreaded code, providing a valuable behind-the-scenes account of OpenMP program performance. Finally, Using OpenMP considers trends likely to influence OpenMP development, offering a glimpse of the possibilities of a future OpenMP 3.0 from the vantage point of the current OpenMP 2.5. With multicore computer use increasing, the need for a comprehensive introduction and overview of the standard interface is clear. Using OpenMP provides an essential reference not only for students at both undergraduate and graduate levels but also for professionals who intend to parallelize existing codes or develop new parallel programs for shared memory computer architectures.
Download or read book Graph Colouring and the Probabilistic Method written by Michael Molloy and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, many major advances have been made in the field of graph coloring via the probabilistic method. This monograph, by two of the best on the topic, provides an accessible and unified treatment of these results, using tools such as the Lovasz Local Lemma and Talagrand's concentration inequality.
Download or read book Analysis and Optimization of Systems written by Alain Bensoussan and published by . This book was released on 1986 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Integrated Project Management and Control written by Mario Vanhoucke and published by Springer. This book was released on 2014-07-08 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an integrated approach to monitoring projects in progress using Earned Value and Earned Schedule Management combined with Schedule Risk Analysis. Monitoring and controlling projects involves processes for identifying potential problems in a timely manner. When necessary, corrective actions can be taken to exploit project opportunities or to get faltering projects back on track. The prerequisite is that project performance is observed and measured regularly to identify variances from the project baseline schedule. Therefore, monitoring the performance of projects in progress requires a set of tools and techniques that should ideally be combined into a single integrated system. The book offers a valuable resource for anyone who wants to understand the theory first and then to use it in practice with software tools. It is intended for students, professionals and academics with an interest and/or experience in running projects as well as for newcomers in the area of project control with a basic grasp of the Earned Value, Earned Schedule and Schedule Risk Analysis concepts.
Download or read book Handbook on Semidefinite Conic and Polynomial Optimization written by Miguel F. Anjos and published by Springer Science & Business Media. This book was released on 2011-11-19 with total page 955 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semidefinite and conic optimization is a major and thriving research area within the optimization community. Although semidefinite optimization has been studied (under different names) since at least the 1940s, its importance grew immensely during the 1990s after polynomial-time interior-point methods for linear optimization were extended to solve semidefinite optimization problems. Since the beginning of the 21st century, not only has research into semidefinite and conic optimization continued unabated, but also a fruitful interaction has developed with algebraic geometry through the close connections between semidefinite matrices and polynomial optimization. This has brought about important new results and led to an even higher level of research activity. This Handbook on Semidefinite, Conic and Polynomial Optimization provides the reader with a snapshot of the state-of-the-art in the growing and mutually enriching areas of semidefinite optimization, conic optimization, and polynomial optimization. It contains a compendium of the recent research activity that has taken place in these thrilling areas, and will appeal to doctoral students, young graduates, and experienced researchers alike. The Handbook’s thirty-one chapters are organized into four parts: Theory, covering significant theoretical developments as well as the interactions between conic optimization and polynomial optimization; Algorithms, documenting the directions of current algorithmic development; Software, providing an overview of the state-of-the-art; Applications, dealing with the application areas where semidefinite and conic optimization has made a significant impact in recent years.
Download or read book CIKM 13 written by CIKM 13 Conference Committee and published by . This book was released on 2013-10-27 with total page 938 pages. Available in PDF, EPUB and Kindle. Book excerpt: CIKM'13: 22nd ACM International Conference on Information and Knowledge Management Oct 27, 2013-Nov 01, 2013 San Francisco, USA. You can view more information about this proceeding and all of ACM�s other published conference proceedings from the ACM Digital Library: http://www.acm.org/dl.
Download or read book Large Scale Network Centric Distributed Systems written by Hamid Sarbazi-Azad and published by John Wiley & Sons. This book was released on 2013-10-10 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: A highly accessible reference offering a broad range of topics and insights on large scale network-centric distributed systems Evolving from the fields of high-performance computing and networking, large scale network-centric distributed systems continues to grow as one of the most important topics in computing and communication and many interdisciplinary areas. Dealing with both wired and wireless networks, this book focuses on the design and performance issues of such systems. Large Scale Network-Centric Distributed Systems provides in-depth coverage ranging from ground-level hardware issues (such as buffer organization, router delay, and flow control) to the high-level issues immediately concerning application or system users (including parallel programming, middleware, and OS support for such computing systems). Arranged in five parts, it explains and analyzes complex topics to an unprecedented degree: Part 1: Multicore and Many-Core (Mc) Systems-on-Chip Part 2: Pervasive/Ubiquitous Computing and Peer-to-Peer Systems Part 3: Wireless/Mobile Networks Part 4: Grid and Cloud Computing Part 5: Other Topics Related to Network-Centric Computing and Its Applications Large Scale Network-Centric Distributed Systems is an incredibly useful resource for practitioners, postgraduate students, postdocs, and researchers.
Download or read book Biomimicry written by Janine M. Benyus and published by Harper Collins. This book was released on 2009-08-11 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Repackaged with a new afterword, this "valuable and entertaining" (New York Times Book Review) book explores how scientists are adapting nature's best ideas to solve tough 21st century problems. Biomimicry is rapidly transforming life on earth. Biomimics study nature's most successful ideas over the past 3.5 million years, and adapt them for human use. The results are revolutionizing how materials are invented and how we compute, heal ourselves, repair the environment, and feed the world. Janine Benyus takes readers into the lab and in the field with maverick thinkers as they: discover miracle drugs by watching what chimps eat when they're sick; learn how to create by watching spiders weave fibers; harness energy by examining how a leaf converts sunlight into fuel in trillionths of a second; and many more examples. Composed of stories of vision and invention, personalities and pipe dreams, Biomimicry is must reading for anyone interested in the shape of our future.
Download or read book Sampling in Combinatorial and Geometric Set Systems written by Nabil H. Mustafa and published by American Mathematical Society. This book was released on 2022-01-14 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the behavior of basic sampling techniques and intrinsic geometric attributes of data is an invaluable skill that is in high demand for both graduate students and researchers in mathematics, machine learning, and theoretical computer science. The last ten years have seen significant progress in this area, with many open problems having been resolved during this time. These include optimal lower bounds for epsilon-nets for many geometric set systems, the use of shallow-cell complexity to unify proofs, simpler and more efficient algorithms, and the use of epsilon-approximations for construction of coresets, to name a few. This book presents a thorough treatment of these probabilistic, combinatorial, and geometric methods, as well as their combinatorial and algorithmic applications. It also revisits classical results, but with new and more elegant proofs. While mathematical maturity will certainly help in appreciating the ideas presented here, only a basic familiarity with discrete mathematics, probability, and combinatorics is required to understand the material.
Download or read book Optimal Shape Design for Elliptic Systems written by O. Pironneau and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of optimal shape design can be arrived at by asking the following question: "What is the best shape for a physical system?" This book is an applications-oriented study of such physical systems; in particular, those which can be described by an elliptic partial differential equation and where the shape is found by the minimum of a single criterion function. There are many problems of this type in high-technology industries. In fact, most numerical simulations of physical systems are solved not to gain better understanding of the phenomena but to obtain better control and design. Problems of this type are described in Chapter 2. Traditionally, optimal shape design has been treated as a branch of the calculus of variations and more specifically of optimal control. This subject interfaces with no less than four fields: optimization, optimal control, partial differential equations (PDEs), and their numerical solutions-this is the most difficult aspect of the subject. Each of these fields is reviewed briefly: PDEs (Chapter 1), optimization (Chapter 4), optimal control (Chapter 5), and numerical methods (Chapters 1 and 4).
Download or read book Nondifferentiable Optimization written by Philip Wolfe and published by . This book was released on 1975 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optimization of Distributed Parameter Structures written by Edward J. Haug and published by Kluwer Academic Publishers. This book was released on 1981 with total page 796 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ultra Wide Band Antennas written by Xavier Begaud and published by John Wiley & Sons. This book was released on 2013-03-04 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recognized studies.
Download or read book Random Trees written by Michael Drmota and published by Springer Science & Business Media. This book was released on 2009-04-16 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to provide a thorough introduction to various aspects of trees in random settings and a systematic treatment of the mathematical analysis techniques involved. It should serve as a reference book as well as a basis for future research.
