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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
701

Flow-shop with time delays, linear modeling and exact solution approaches / Flow-shop avec temps de transport, modélisation linéaire et approches de résolution exacte

Mkadem, Mohamed Amine 07 December 2017 (has links)
Dans le cadre de cette thèse, nous traitons le problème de flow-shop à deux machines avec temps de transport où l’objectif consiste à minimiser le temps de complétion maximal. Dans un premier temps, nous nous sommes intéressés à la modélisation de ce problème. Nous avons proposé plusieurs programmes linéaires en nombres entiers. En particulier, nous avons introduit une formulation linéaire basée sur une généralisation non triviale du modèle d’affectation pour le cas où les durées des opérations sur une même machine sont identiques. Dans un deuxième temps, nous avons élargi la portée de ces formulations mathématiques pour développer plusieurs bornes inférieures et un algorithme exact basé sur la méthode de coupe et branchement (Branch-and-Cut). En effet, un ensemble d’inégalités valides a été considéré afin d’améliorer la relaxation linéaire de ces programmes et d’accélérer leur convergence. Ces inégalités sont basées sur la proposition de nouvelles règles de dominance et l’identification de sous-instances faciles à résoudre. L’identification de ces sous-instances revient à déterminer les cliques maximales dans un graphe d’intervalles. En plus des inégalités valides, la méthode exacte proposée inclut la considération d’une méthode heuristique et d’une procédure visant à élaguer les nœuds. Enfin, nous avons proposé un algorithme par séparation et évaluation (Branch-and-Bound) pour lequel, nous avons introduit des règles de dominance et une méthode heuristique basée sur la recherche locale. Nos expérimentations montrent l’efficacité de nos approches qui dominent celles de la littérature. Ces expérimentations ont été conduites sur plusieurs classes d’instances qui incluent celles de la littérature, ainsi que des nouvelles classes d’instances où les algorithmes de la littérature se sont montrés peu efficaces. / In this thesis, we study the two-machine flow-shop problem with time delays in order to minimize the makespan. First, we propose a set of Mixed Integer Programming (MIP) formulations for the problem. In particular, we introduce a new compact mathematical formulation for the case where operations are identical per machine. The proposed mathematical formulations are then used to develop lower bounds and a branch-and-cut method. A set of valid inequalities is proposed in order to improve the linear relaxation of the MIPs. These inequalities are based on proposing new dominance rules and computing optimal solutions of polynomial-time-solvable sub-instances. These sub-instances are extracted by computing all maximal cliques on a particular Interval graph. In addition to the valid inequalities, the branch-and-cut method includes the consideration of a heuristic method and a node pruning procedure. Finally, we propose a branch-and-bound method. For which, we introduce a local search-based heuristic and dominance rules. Experiments were conducted on a variety of classes of instances including both literature and new proposed ones. These experiments show the efficiency of our approaches that outperform the leading methods published in the research literature.
702

Meta-heurísticas Iterated Local Search, GRASP e Artificial Bee Colony aplicadas ao Job Shop Flexível para minimização do atraso total. / Meta-heuristics Iterated Local Search, GRASP and Artificial Bee Colony applied to Flexible Job Shop minimizing total tardiness.

Everton Luiz de Melo 07 February 2014 (has links)
O ambiente de produção abordado neste trabalho é o Job Shop Flexível (JSF), uma generalização do Job Shop (JS). O problema de programação de tarefas, ou jobs, no ambiente JS é classificado por Garey; Johnson e Sethi (1976) como NP-Difícil e o JSF é, no mínimo, tão difícil quanto o JS. O JSF é composto por um conjunto de jobs, cada qual constituído por operações. Cada operação deve ser processada individualmente, sem interrupção, em uma única máquina de um subconjunto de máquinas habilitadas. O principal critério de desempenho considerado é a minimização dos atrasos dos jobs. São apresentados modelos de Programação Linear Inteira Mista (PLIM) para minimizar o atraso total e o instante de término da última operação, o makespan. São propostas novas regras de prioridade dos jobs, além de adaptações de regras da literatura. Tais regras são utilizadas por heurísticas construtivas e são aliadas a estratégias cujo objetivo é explorar características específicas do JSF. Visando aprimorar as soluções inicialmente obtidas, são propostas buscas locais e outros mecanismos de melhoria utilizados no desenvolvimento de três meta-heurísticas de diferentes categorias. Essas meta-heurísticas são: Iterated Local Search (ILS), classificada como meta-heurística de trajetória; Greedy Randomized Adaptive Search (GRASP), meta-heurística construtiva; e Artificial Bee Colony (ABC), meta-heurística populacional recentemente proposta. Esses métodos foram selecionados por alcançarem bons resultados para diversos problemas de otimização da literatura. São realizados experimentos computacionais com 600 instâncias do JSF, permitindo comparações entre os métodos de resolução. Os resultados mostram que explorar as características do problema permite que uma das regras de prioridade propostas supere a melhor regra da literatura em 81% das instâncias. As meta-heurísticas ILS, GRASP e ABC chegam a conseguir mais de 31% de melhoria sobre as soluções iniciais e a obter atrasos, em média, somente 2,24% superiores aos das soluções ótimas. Também são propostas modificações nas meta-heurísticas que permitem obter melhorias ainda mais expressivas sem aumento do tempo de execução. Adicionalmente é estudada uma versão do JSF com operações de Montagem e Desmontagem (JSFMD) e os experimentos realizados com um conjunto de 150 instâncias também indicam o bom desempenho dos métodos desenvolvidos. / The production environment addressed herein is the Flexible Job Shop (FJS), a generalization of the Job Shop (JS). In the JS environment, the jobs scheduling problem is classified by Garey; Johnson and Sethi (1976) as NP-Hard and the FJS is at least as difficult as the JS. FJS is composed of a set of jobs, each consisting of operations. Each operation must be processed individually, without interruption, in a single machine of a subset of enabled machines. The main performance criterion is minimizing the jobs tardiness. Mixed Integer Linear Programming (MILP) models are presented. These models minimize the total tardiness and the completion time of the last operation, makespan. New priority rules of jobs are proposed, as well as adaptations of rules from the literature. These rules are used by constructive heuristics and are combined with strategies aimed at exploiting specific characteristics of FSJ. In order to improve the solutions initially obtained, local searches and other improvement mechanisms are proposed and used in the development of metaheuristics of three different categories. These metaheuristics are: Iterated Local Search (ILS), classified as trajectory metaheuristic; Greedy Randomized Adaptive Search (GRASP), constructive metaheuristic, and Artificial Bee Colony (ABC), recently proposed population metaheuristic. These methods were selected owing to their good results for various optimization problems in the literature. Computational experiments using 600 FJS instances are carried out to allow comparisons between the resolution methods. The results show that exploiting the characteristics of the problem allows one of the proposed priority rules to exceed the best literature rule in about 81% of instances. Metaheuristics ILS, GRASP and ABC achieve more than 31% improvement over the initial solutions and obtain an average tardiness only 2.24% higher than the optimal solutions. Modifications in metaheuristics are proposed to obtain even more significant improvements without increased execution time. Additionally, a version called Disassembly and Assembly FSJ (DAFJS) is studied and the experiments performed with a set of 150 instances also indicate good performance of the methods developed.
703

Le problème de job-shop avec transport : modélisation et optimisation / Job-shop with transport : its modelling and optimisation

Larabi, Mohand 15 December 2010 (has links)
Dans cette thèse nous nous sommes intéressés à l’extension du problème job-shop en ajoutant la contrainte du transport des jobs entre les différentes machines. Dans cette étude nous avons retenu l’existence de deux types de robots, les robots de capacité de chargement unitaire (capacité=1 veut dire qu’un robot ne peut transporter qu’un seul job à la fois) et les robots de capacité de chargement non unitaire (capacité>1 veut dire qu’un robot peut transporter plusieurs job à la fois). Nous avons traité cette extension en deux étapes. Ainsi, la première étape est consacrée au problème du job-shop avec plusieurs robots de capacité de chargement unitaire et en seconde étape en ajoutant la capacité de chargement non unitaire aux robots. Pour les deux problèmes étudiés nous avons proposé :• Une modélisation linéaire ;• Une modélisation sous forme de graphe disjonctif ;• Plusieurs heuristiques de construction de solutions ;• Plusieurs recherches locales qui améliorent les solutions obtenues ;• Utilisation des algorithmes génétiques / mémétiques comme schéma global d’optimisation ;• De nouveaux benchmarks, des résultats de test de nos approches sur nos benchmarks et ceux de la littérature et ces résultats sont commentés et comparés à ceux de la littérature. Les résultats obtenus montrent la pertinence de notre modélisation ainsi que sa qualité. / In this thesis we are interested in the extension of the job-shop problem by adding the constraint of transport of jobs between different machines. In this study we used two types of robots, robots with unary loading capacity (capacity =1 means that each robot can carry only one job at a time,) and robots with non unary loading capacities (robot with capacity >1 can carry more than one job at time). Thus, the first step is devoted to the problem of job-shop with several robots with unary loading capacity. In the second step we extend the problem by adding the non-unary loading capacities to the robots. For both problems studied we have proposed :• A linear modeling ;• A Disjunctive graph Model ;• Several constructive heuristics ;• Several local searches methods that improve the obtained solutions ;• Use of genetic / memetic algorithms as a global optimization schema ;• New benchmarks, test results of our approaches on our benchmarks and those present in the literature and these results are commented and compared with those of literature. The results show the relevance of our model and its quality.
704

Internetový obchod / E-shop

Žák, David January 2009 (has links)
The work deals with internet commerce. It includes analysis and design their own e-shop. The aim was to bring the marketing plan for market entry, assess the achievements and propose a procedure to other years. It can be familiar with basic knowledge about internet marketing, internet business analysis in comparison with the stone business. These general theoretical and practical knowledge is given to about half the work. In the second half is giving its own Internet business, the introduction of the marketing and promotion.
705

Polyfunkční dům ve Frýdku-Místku / Multifunkcional building in Frýdek-Místek

Suchý, Petr January 2015 (has links)
The subject of this thesis is the preparation of project documentation multifunctional building. It is a five-storey building with a basement. The roof structure is designed as a single-layer, flat roof. The building is divided into three working parts. Prví part is used for housing. It consists of 18 housing units, one of which is designed for wheelchair use. The second part of the building is intended for the public. This area retail sales. Includes store books, toys shop, newsagent and a hairdressing salon. The last part of it is public garage. It is intended for users of residential units.
706

Informační systém realitní kanceláře / Information System for Estate Agency

Dudík, Michal January 2008 (has links)
This work deals with the requirements analysis of the online content management system of real estate agency. The aim of the work is to suggest and implement this system. The emphasis is mainly on the possibility of data synchronization with Czech real estate servers. On the basis of the appreciation of several different methods used for the data exchange there are illustrated their benefits and disadvantages. Ascertained matter will be used for the proposal of the method of synchronization among real estate systems. System is built by using PHP 5 and MySQL, XML, XSLT, XHTML, CSS, JavaScript, XML-RPC technologies.
707

WebLang: A Prototype Modelling Language for Web Applications : A Meta Attack Language based Domain Specific Language for web applications / WebLang: Ett Prototypmodelleringsspråk för Web Applikationer : Ett Meta Attack Language baserat Domän Specifikt Språk för Web Applikationer

af Rolén, Mille, Rahmani, Niloofar January 2023 (has links)
This project explores how a Meta Attack Language based Domain Specific Language for web applications can be used to threat model web applications in order to evaluate and improve web application security. Organizations and individuals are targeted by cyberattacks every day where malicious actors could gain access to sensitive information. These malicious actors are also developing new and innovative ways to exploit the many different components of web applications. Web applications are becoming more and more complex and the increasingly complex architecture gives malicious actors more components to target with exploits. In order to develop a secure web application, developers have to know the ins and outs of web application components and web application security. The Meta Attack Language, a framework for developing domain specific languages, was recently developed and has been used to create languages for domains such as Amazon Web Services and smart cars but no language previously existed for web applications. This project presents a prototype web application language delimited to the first vulnerability in the top ten list provided by Open Worldwide Application Security Project (OWASP), which is broken access control, and tests it against the OWASP juice shop, which is an insecure web application developed by OWASP to test new tools. Based on the results it is concluded that the prototype can be used to model web application vulnerabilities but more work needs to be done in order for the language to work on any given web application and vulnerability. / Detta projekt utforskar hur ett Meta Attack Language baserat Domän Specifikt Språk för webbapplikationer kan användas för att hotmodellera samt undersöka och förbättra webbapplikationssäkerhet. Organisationer och individer utsätts dagligen för cyberattacker där en hackare kan få tillgång till känslig information. Dessa hackare utverklar nya och innovativa sätt att utnyttja dem många olika komponenterna som finns i webbapplikationer. Webbapplikationer blir mer och mer komplexa och denna ökande komplexa arkitekturen leder till att det finns mer mål för en hackare att utnyttja. För att utveckla en säker webbapplikation måste utvecklare veta allt som finns om webbapplikations komponenter och webbapplikations säkerhet. Meta Attack Language är ett ramverk för att utveckla nya språk för domäner som till exempel Amazon Web Services och smarta fordon men innan detta existerade inget språk för webbapplikationer. Detta projekt presenterar en webbapplikations språk prototyp som är avgränsad till den första sårbarheten i top tio listan av Open Worldwide Application Security Project (OWASP) vilket är broken access control, och testar den mot OWASP juice shop, vilket är en sårbar webapplikation som utveckalts av OWASP för att testa nya verktyg. Baserat på resultaten dras slutsatsen att prototypen kan användas för att modellera webbapplikations sårbarheter men att det behövs mer arbete för att språket ska fungera på vilken webbapplikation och sårbarhet som helst.
708

Patent ownership : rights to employee inventions

McBride, Vanessa Ann 11 1900 (has links)
A patent is an intellectual property right granted as a reward for the labours of the inventor so as to commercially exploit the invention in return for disclosure of the invention. The benefits of the patent system find perfect expression in the employment situation since the employer is better equipped to exploit the invention through provision of resources and capital whereas the employee is provided with an opportunity to develop his technical know-how. A comparative study of the laws pertaining to employee inventions in the United Kingdom, Federal Republic of Germany and the United States of America reveals a variety of approaches to the subject of employee inventions. The approach of the South African law on the subject is inadequate and legal reform is a necessity. The recommendations for such reform encapsulates a blend of the best features of each of the three national approaches to employee inventions. / Mercentile Law / LL. M. (Law)
709

Le problème de job-shop avec transport : modélisation et optimisation

Larabi, Mohand 15 December 2010 (has links) (PDF)
Dans cette thèse nous nous sommes intéressés à l'extension du problème job-shop en ajoutant la contrainte du transport des jobs entre les différentes machines. Dans cette étude nous avons retenu l'existence de deux types de robots, les robots de capacité de chargement unitaire (capacité=1 veut dire qu'un robot ne peut transporter qu'un seul job à la fois) et les robots de capacité de chargement non unitaire (capacité>1 veut dire qu'un robot peut transporter plusieurs job à la fois). Nous avons traité cette extension en deux étapes. Ainsi, la première étape est consacrée au problème du job-shop avec plusieurs robots de capacité de chargement unitaire et en seconde étape en ajoutant la capacité de chargement non unitaire aux robots. Pour les deux problèmes étudiés nous avons proposé :* Une modélisation linéaire ;* Une modélisation sous forme de graphe disjonctif ;* Plusieurs heuristiques de construction de solutions ;* Plusieurs recherches locales qui améliorent les solutions obtenues ;* Utilisation des algorithmes génétiques / mémétiques comme schéma global d'optimisation ;* De nouveaux benchmarks, des résultats de test de nos approches sur nos benchmarks et ceux de la littérature et ces résultats sont commentés et comparés à ceux de la littérature. Les résultats obtenus montrent la pertinence de notre modélisation ainsi que sa qualité.
710

Influence des structures commerciales de types lifestyle centers sur la centralité de leurs régions périphériques : le cas du Quartier DIX30 à Brossard

Luis, William 11 1900 (has links)
Le commerce a connu à travers le temps de nombreuses évolutions, tant dans sa forme que dans son implantation, passant de grands magasins prestigieux dans le cœur des villes au début du XXe siècle à de grands centres commerciaux à la jonction d’autoroute dans les années 2000. Le lifestyle center est la forme commerciale la plus aboutie, concept américain existant depuis les années 80, il est apparu pour la première fois au Québec en 2006 à Brossard sur la Rive-Sud de Montréal. Ses caractéristiques hors du commun ; une surface de vente de près de 2 000 000 pi² faisant de lui un centre d’envergure supra régional, son agencement de boutiques en plein air regroupé autour d’une rue piétonne ainsi qu’un mix commercial extrêmement varié rompt avec les traditionnels centres commerciaux existants. Ainsi en s’implantant à Brossard le Quartier DIX30 est venu modifier profondément la structure commerciale de la Rive-Sud en s’imposant comme un contre poids de taille par rapport à la domination du pôle des Promenades Saint-Bruno. Cependant, le Quartier DIX30 ne va pas seulement modifier cette structure commerciale, mais plus globalement la centralité urbaine de la Rive-Sud en s’imposant comme un pôle central majeur. Le Quartier DIX30 grâce à sa mixité d’activité et son concept favorisant les interactions sociales est en train d’insuffler un mouvement de concentration d’activité commerciale et tertiaire. Ainsi aujourd’hui se développe au pourtour du Quartier DIX30 de nombreux locaux à bureaux. Cependant, cette nouvelle centralité créée par le Quartier DIX30 soulève des interrogations notamment vis-à-vis de la privatisation d’un espace s’imposant de plus en plus comme un des pôles principaux de croissance de la Rive-Sud. Ainsi, une question légitime se pose, ne sommes-nous pas en train d’assister à une privatisation d’un centre-ville en devenir ? / Over the time, trade has knew numerous changes in term of location and form, passing from prestigious department stores in the heart of cities in the early twentieth century to large shopping centers at the junction of highways in the years 2000. The lifestyle center is the most accomplished commercial form, the American concept exists since the years 1980 and it appeared for the first time in Quebec in 2006 in Brossard on the South Shore of Montreal. Its unusual features: a sales area of almost 2 000 000 square feet (making it a center of supra-regional scale), a mix of shops clustered around a pedestrian street and numerous other activities, breaks with the traditional agencement of the existing shopping malls. Thus, by becoming established in Brossard, the Quartier DIX30 modifies profoundly the commercial structure of the South Shore of Montréal. The Quartier DIX30 imposes itself as a major commercial pole against the domination of the Promenades Saint Bruno. The Quartier DIX30 will not only change the commercial structure of the South Shore, but more generally the urban centrality of the South Shore established itself as a major center pole. Due to the variety of activities and its concept of mix of shops clustered around a pedestrian street permitting social interaction, the Quartier DIX30 creates a commercial and office concentration. Thus, today develops around the Quartier DIX30 many building with offices. However, this new centrality created by the Quartier DIX30 raises interrogations in particular with respect to the privatization of a space imposing itself more and more like one of the principal poles of growth of the South Shore. Thus, a question legitimate is posed, does we aren't attending a privatization of a downtown area in becoming?

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