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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.
1

L'ambivalence juridique de l'humain : entre sacralité et disponibilité / The legal ambivalence of the human : between sacred and availability

Reynier, Mathieu 10 November 2010 (has links)
L'ambivalence entourant actuellement l'appréhension de l'humain confine parfois à l'ambiguïté. Telle est le constat auquel le chercheur se doit de faire face dès lors qu'il s'attache à étudier ce vaste sujet. Tiraillé entre deux mouvements opposés, l'humain semble osciller entre sacralité et disponibilité, entre protection et libéralisation. Il est soumis à un mouvement permanent d'appréciations contradictoires, rendant délicate, et peut être même illusoire, toute fixation d'une appréhension pérenne. Pourtant, paradoxalement, la nécessité de dégager un axiome durable destiné à guider les réflexions n'a jamais été aussi grande. Car, les développements scientifiques, la montée du libéralisme, mais également l'apparition d'un individualisme social projettent l'humain dans un mouvement utilitariste suscitant parfois l'inquiétude. L'outil juridique dans sa "rigidité" a en effet du mal à percevoir cette réalité particulière. Il n'a pas été originellement créé dans ce but. Il sait s'occuper des rapports pouvant exister entre les catégories qu'il a établies, mais rencontre quelques difficultés lorsqu'il s'agit d'appréhender une entité "hors-cadre". Dès lors, pour véritablement comprendre nous nous devons de nous installer dans une "schizophrénie" analytique. Nous devons accepter que l'humain ne représente pas en droit, une personne ou une chose, mais bien les deux à la fois. Qu'il ne peut être "sacralisé" ni rendu "disponible" complètement. Qu'il est un "tout" complexe et un "complexe" de tout, qu'il est une unicité "janusienne", une unicité à double visage. / The ambivalence surrounding at present the apprehension of the human sometimes borders on the ambiguity. Such is the report which the researcher owes face since he attempts to study this vast subject. Pulled between two opposite movements, human seems to oscillate between sacrality and availability, between protection and liberalization. It is subjected to a permanent movement of contradictory appreciations, making delicate, and can be even imaginary, any binding of a long-lasting apprehension. Nevertheless, paradoxically, the necessity of loosening a sustainable axiom intended to guide the reflections was never so big. Because, the scientific developments, the ascent of the liberalism, but also the appearance of a social individualism plan human in a movement utilitarian sometimes arousing the anxiety. The legal tool in its "rigidity" indeed has difficulty in perceiving this particular reality. It was not create originally in this purpose. He knows how to take care of connections which can exist between the categories that he established, but meets some difficulties when it is a question of dreading an entity "except frame". From then on, to understand really we owesettle down in an analytical "schizophrenia". We have to accept that human does not represent in law, a person or a thing, but both at once. That he cannot be "made sacred" nor made "available" completely. That it is a "quite" complex and a "complex" of everything, that it is a uniqueness "janusienne", a uniqueness with double face.
2

Reconfiguration dynamique des architectures orientées services

Fredj, Manel 10 December 2009 (has links) (PDF)
Reconfiguration dynamique des architectures orientées services
3

Ordonnancement de tâches et de périodes d’indisponibilité de durée variable / Scheduling problems of jobs and unavailability periods

Gara-Ali, Ahmed 19 July 2016 (has links)
Dans cette thèse, nous nous intéressons aux problèmes d'ordonnancement simultané de tâches et de périodes d'indisponibilité. Dans un premier temps, nous réalisons une revue de littérature sur la prise en compte des indisponibilités dans les problèmes d'ordonnancement.Ensuite, nous définissons un modèle général qui englobe des modèles existants de la littérature pour des ateliers à une machine et à machines parallèles. Une approche globale de résolution basée sur les problèmes d'affectation linéaire a été développée. Cette approche permet de résoudre le modèle général comme un simple problème d'affectation. Un grand nombre de critères d'optimisation et de modèles de maintenance peuvent être traités en utilisant cette approche, fournissant ainsi l'accès à tous les modèles qui ont souvent été étudiés séparément dans la littérature. Les résultats élaborés avec cette approche ont permis de résoudre des problèmes d'ordonnancement non traités avant et aussi de généraliser et améliorer des résultats antérieurs.Nous proposons, en dernier lieu, une étude d'un problème flow shop à deux machines en présence d'une période d'indisponibilité sur la deuxième machine. Une étude de complexité est menée sur le problème. Ensuite, nous définissons des propriétés d'optimalité. En se basant sur ces propriétés, trois méthodes de résolution exacte sont proposées; une méthode énumérative, un programme linéaire et une méthode basée sur l'approche de séparation et évaluation B&B. Une analyse expérimentale est présentée afin d'évaluer les performances de ces méthodes. / In classical scheduling problems, machines are assumed to be continuously available. However, in a real manufacturing system, machine may become unavailable during the scheduling period due to preventive maintenance. In this dissertation, we are interested in the problems of jointly scheduling jobs and unavailability periods.We start our study by introducing a general framework for scheduling problems and we present a review of the scheduling problems with unavailability periods.Then, we consider a general model for scheduling jobs on single-machine and unrelated parallel-machines with maintenance interventions. A unified approach is presented to solve this model as an assignment problem. A large number of performance criteria and maintenance models can be treated in this way, thus providing access to models that have often been studied separately in the published literature.Finally, we focus on the problem of a two-machine flow-shop makespan scheduling with the deteriorating maintenance period on the second machine. Then, we establish some conditions of the optimal schedule. In order to solve the problem, we proposed different exact methods: enumerative method, mixed-integer programming (MIP) model and a branch & bound algorithm. Numerical experiments are reported for all the proposed methods.
4

Ordonnancement de tâches parallèles dans les environnements fortement perturbés / Scheduling parallel tasks in very disturted environments

Safi, Adel 15 October 2012 (has links)
La démocratisation des nouvelles plateformes d'exécution parallèles et distribuées, notamment les grilles de calcul, a engendré l'émergence de nouvelles d'architectures constituées en grande partie par des ressources fournies par des personnes/organisations volontaires. Ces machines ne sont pas disponibles tout le temps. Elles sont sujettes à des perturbations liées aux incertitudes sur les dates de début et de fin de disponibilités. Pour générer des ordonnancements adaptés à ces plateformes, nous cherchons à optimiser, en plus des fonctions objectifs classiques, un nouveau critère qui caractérise l'aptitude de l'ordonnancement à absorber l'effet des perturbations (la stabilité). Nous nous sommes intéressés dans le cadre de ce travail au problème de l'ordonnancement avec contraintes d'indisponibilité de ressources et d'incertitudes sur les dates d'occurrence des évènements. Nous commençons par étudier le cas préliminaire de ce problème où une seule indisponibilité est possible par machine et où l'incertitude porte sur la durée de l'indisponibilité. Nous généralisons ensuite cette étude pour le cas où plusieurs indisponibilités peuvent être envisagées sur les machines et où l'incertitude porte sur les dates d'occurrences des évènements. Pour l'ensemble de ces problèmes, nous utilisons une technique de tampon pour fournir une famille d'ordonnancements qui optimisent simultanément la performance et la stabilité des ordonnancements générés. Une vaste campagne de simulation des heuristiques proposées conduit à la sélection de configurations qui aboutissent à des résultats satisfaisants en terme de compromis. Mots clés : Parallélisme, ordonnancement, incertitude, disponibilité, stabilité / New platforms for parallel and distributed computing, such grids, are emergent structure build by collecting resources provided by volunteers individuals or organisations. These resources are not always available. They are in fact subject to disturbances related to uncertainty on start and end availability time. In order to design schedules adapted to these platforms we aim to optimise, in addition to the classic objective function, a new criteria that characterise the ability of the schedule to absorb the effect of the perturbation (stability). In this work, we study the problem of scheduling under availability resource constraints and uncertainty on the events occurrence dates. We initially study the elementary case where only one unavailability is allowed per machine and where the duration of the availability is uncertain. We then generalize to the general case when multiple unavailabilities are allowed by machine and where uncertainties are related on the events occurrence dates. For all these problems, we design schedules based on the slack technique, and that optimise both performance and stability. A wide simulation campaign of the designed heuristics lead to the identification of configurations that produces satisfactory results.
5

Implantação de melhorias na gestão da manutenção de subestações elétricas em empresa do ramo de bebidas

Roberto Rennó Sinohara da Silva Sousa 02 August 2014 (has links)
Nesta dissertação é apresentada a análise, desenvolvimento e aplicação de ferramentas para melhoria no sistema de gestão da manutenção de subestações do sistema elétrico de uma empresa do ramo de bebidas composta por algumas dezenas de plantas que trabalham em regime ininterrupto. O sistema de gestão da manutenção aplicado nesta empresa é condizente com o que sugere a literatura e apresenta resultados satisfatórios em vários setores. No entanto, pode-se constatar algumas dificuldades e fatores negativos na gestão do sistema elétrico da empresa, que funciona em três turnos. As limitações impostas ao sistema de gestão da manutenção comprometem sua eficiência gerando um nível indesejado de indisponibilidade por energia elétrica. A manutenção preventiva é realizada em paradas de fabricas de tempo reduzido. A localização geográfica bem como a extensão do sistema elétrico das plantas impõe que sejam contratadas diversas empresas para realizar estas manutenções. Esta diversidade traz grande dificuldade no tratamento dos dados de ensaios e de anomalias detectadas e apresentados nos relatórios de manutenção. O objetivo principal desta dissertação é apresentar uma análise crítica do sistema atual de gestão da manutenção das subestações do setor elétrico e uma proposta para melhorar este sistema de gestão quanto à sua aplicação no setor elétrico. Esta proposta se baseia na correção das distorções no índice de indisponibilidade e em uma ferramenta para aperfeiçoar o tratamento das informações resultantes da manutenção preventiva para sua utilização tanto no monitoramento do sistema quanto para embasar o processo decisório de priorização das manutenções corretivas e de investimento. O trabalho apresenta ainda o emprego dos conceitos que fundamentam a ferramenta proposta antes da aplicação da mesma e os impactos em indisponibilidade resultantes da aplicação destes conceitos. / This work presents the analysis, development and application of tools to improve the electrical substations maintenance management system of a beverage company composed of dozens of plants working continuously. The maintenance management system used in this company is consistent with what the literature suggests and provides satisfactory results in various sectors. However, we can notice some difficulties and negative factors in managing the electrical system of the company, which operates in three shifts. The limitations imposed on the maintenance management system compromise their efficiency generating an undesirable level of electrical power unavailability. Preventive maintenance is carried out in short time factory interruptions. The geographical location and the extent of the electrical system of the plants requires several companies to be hired to perform these maintenances. This diversity brings great difficulty in the treatment of tests and deficiencies data presented in the reports. The main objective of this dissertation is to present a critical analysis of the current substations maintenance management system in the electrical sector and a proposal to improve the management system in its application in the electrical sector. This proposal is based on correcting the distortions in the unavailability index and a tool to enhance the processing of information resulting from preventive maintenance to be used both for monitoring the system and to support the decision making process of prioritization of corrective maintenance and investment. The paper also describes the use of the concepts on which the proposed tool is based before implementation and impact on unavailability resulting from the application of these concepts.
6

[en] RAIN UNAVAILABILITY PREDICTION ON VSAT NETWORKS IN BRAZIL / [pt] PREDIÇÃO DA INDISPONIBILIDADE POR CHUVAS EM REDES VSAT NO BRASIL

LUIS EDUARDO MENEZES FELIX 21 September 2004 (has links)
[pt] Em comunicações Via-Satélite, o regime de chuvas brasileiro se apresenta como fator limitante na análise da viabilidade de redes VSAT (Very Small Aperture Terminal) nas bandas Ka e Ku. O objetivo do trabalho é analisar a indisponibilidade por chuvas de redes VSAT com topologia em estrela usadas no Brasil para determinados serviços, tais como telefonia e transmissão de dados e TV, utilizando-se cenários hipotéticos em termos da localização das estações terminais, de satélites com transponders nas bandas Ka e Ku e das características reais dos equipamentos e sistemas. Um dos objetivos dentro deste tema foi a análise da influência do modelo de atenuação. Para tal foram utilizadas as duas últimas versões de modelo de atenuação por chuvas que tem sido recomendado pela UIT-R para aplicações em Engenharia. Complementando este objetivo, analisou-se também a influência de dados de taxas de precipitação para o Brasil utilizado nestes modelos, tendo sido utilizadas duas fontes: a Recomendação P.837 do UIT-R e medidas regionais realizadas pelo CETUC. Outro objetivo foi à comparação entre os valores estimados de indisponibilidade com limites máximos recomendados o que permite obter conclusões sobre a viabilidade destes sistemas no Brasil. Complementado o estudo acima descrito, um segundo caso foi analisado correspondendo a um sistema DVBS. O cenário é composto de outro satélite (PAS-9), porém com as mesmas configuração (rede VSAT e topologia em estrela) e estações terrenas com mesmas localizações. A diferença em relação ao primeiro caso reside principalmente na maior taxa de transmissão e por ter sido utilizado na análise da indisponibilidade um modelo de atenuação por chuvas regional, desenvolvido pelo CETUC com base em dados de medidas no Brasil. Uma análise similar foi feita considerando o modelo atual da UIT-R para fins comparativos. / [en] In satellite communication, the Brazilians rains distributions are presented like limited factor in the viability analyze of VSAT networks (Very Small Aperture Terminal) in the bands Ka and Ku. The aim of the work is analyze the unavailable caused by VSAT rains with star topology used in Brazil to some kinds of service, like telephone and data transmission and TV, using conjectural scenes on the satellite s terminal stations with transponders in the bands Ka and Ku and the real characteristics of the equipments and systems. One of the objectives is analyze the influence of the attenuation system. For it were used the last two versions models rainy attenuation that has been recommended by UIT-R for applications in engineering. Completing this objective, were also analyzed the influence precipitation taxes data for Brazil using this models, have been used two fonts: the recommendation P.837 from UIT-R and regional measured realized by CETUC. Other objective was the comparison between unavailable esteem values with maxim limits recommended what allows having conclusions about the viability of these systems in Brazil. Concluding the study, a second case was analyzed corresponding a system. The scene is composed by from other satellite (PAS-9), by the way, with the same localizations. The difference between both are: the first one has a bigger tax of transmission for being used analyze of the unavailable one model of attenuation for regional rains, made by CETUC based on measure data from Brazil. One similar analyze was made considering an actual model of UTI-R for final comparisons.
7

Disengagement, Defection, Abandonment - Why? : A qualitative case study on reasons of disengagement from the Fridays For Future Movement in Västerås, Sweden

Lejdström, Corinne January 2022 (has links)
This study explores a little researched question by the scholars of social movements - why activists disengage before the movement’s goals have been attained. Based on interviews with former and current activists of the Fridays For Future movement in Västerås, this study argues that disengagement occurs due to four reasons, either combined or separately. These are biographical unavailability as a result of other commitments in life, perceived collective inefficacy, emotions of hopelessness either in relation to the movement or climate change, and psychological pressure as a consequence of participation. The results are important as the reasons for disengagement also could illustrate the obstacles for the movement to reach its goals. Without activists who can or want to mobilize, the future of the FFF movement runs the risk of losing the ability to put pressure. On a general notion, the result is also of importance as it manifests the difficulties for all citizens to participate in constitutionally protected political actions as only certain citizens have the opportunity to exercise their freedom of expression.
8

Consumer response to product unavailability

Min, Kyeong Sam 15 October 2003 (has links)
No description available.
9

Resource Allocation in Network Function Virtualization with Workload-Dependent Unavailability / 負荷依存の不可用性を伴うネットワーク機能仮想化における資源割り当て

朱, 梦菲 23 May 2024 (has links)
京都大学 / 新制・課程博士 / 博士(情報学) / 甲第25511号 / 情博第884号 / 新制||情||148(附属図書館) / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 大木 英司, 教授 原田 博司, 教授 山下 信雄 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
10

Evolutionary algorithms for solving job-shop scheduling problems in the presence of process interruptions

Hasan, S. M. Kamrul, Engineering & Information Technology, Australian Defence Force Academy, UNSW January 2009 (has links)
In this thesis, the Job Shop Scheduling Problem (JSSP) is the problem of interest. The classical JSSP is well-known as an NP-hard problem. Although with current computational capabilities, the small problems are solvable using deterministic methods, it is out of reach when they are larger in size. The complexity of JSSP is further increased when process interruptions, such as machine breakdown and/or machine unavailability, are introduced. Over the last few decades, several stochastic algorithms have been proposed to solve JSSPs. However, none of them are suitable for all kinds of problems. Genetic and Memetic algorithms have proved their effectiveness in these regards, because of their diverse searching behavior. In this thesis, we have developed one genetic algorithm and three different Memetic Algorithms (MAs) for solving JSSPs. Three priority rules are designed, namely partial re-ordering, gap reduction and restricted swapping, and these have been used as local search techniques in designing our MAs. We have solved 40 well-known benchmark problems and compared the results obtained with some of the established algorithms available in the literature. Our algorithm clearly outperforms those established algorithms. For better justification of the superiority of MAs over GA, we have performed statistical significance testing (Student's t-test). The experimental results show that MA, as compared to GA, not only significantly improves the quality of solutions, but also reduces the overall computation. We have extended our work by proposing an improved local search technique, shifted gap-reduction (SGR), which improves the performance of MAs when tested with the relatively difficult test problems. We have also modified the new algorithm to accommodate JSSPs with machine unavailability and also developed a new reactive scheduling technique to re-optimize the schedule after machine breakdowns. We have considered two scenarios of machine unavailability. Firstly, where the unavailability information is available in advance (predictive), and secondly, where the information is known after a real breakdown (reactive). We show that the revised schedule is mostly able to recover if the interruptions occur during the early stages of the schedules. We also confirm that the effect of a single continuous breakdown has more impact compared to short multiple breakdowns, even if the total durations of the breakdowns are the same. Finally, for convenience of implementation, we have developed a decision support system (DSS). In the DSS, we have built a graphical user interface (GUI) for user friendly data inputs, model choices, and output generation. This DSS tool will help users in solving JSSPs without understanding the complexity of the problem and solution approaches, as well as will contribute in reducing the computational and operational costs.

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