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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.
31

Service composition in opportunistic networks / Composition de services dans des réseaux opportunistes

Baklouti, Fadhlallah 01 March 2019 (has links)
Cette thèse s’inscrit dans le domaine de l’informatique ambiante et del’Internet des objets, et considère des réseaux qui peuvent se formerspontanément et qui sont composés d’équipements fixes ou mobiles. Ceséquipements peuvent communiquer à travers une infrastructure, ou de gré-à-gré en mode ad hoc. Des ruptures de connectivité peuvent apparaître dans le réseau d’unemanière fréquente et imprévisible. Ces ruptures de connectivité peuvents’avérer problématiques dès lors que ces équipements souhaitent accéder àdes ressources offertes par d’autres équipements.L’informatique opportuniste étend le principe des communicationsopportunistes en proposant d’exposer les ressources à travers des serviceset d’accéder à ces services par des techniques et des protocoles decommunication opportunistes qui mettent en œuvre le principe du “store,carry and forward”.Dans cette thèse, nous nous intéressons à la composition de services afin depouvoir combiner les services élémentaires offerts par les équipementsprésents dans le réseau et ainsi proposer aux utilisateurs des services deplus haut niveau et plus riches. La composition de services représente unetâche complexe dans l’informatique opportuniste du fait des ruptures deconnexion.Dans cette thèse, nous proposons une solution pour composer les servicesen utilisant deux stratégies, à savoir la chorégraphie et l’orchestration. Cettesolution repose en outre sur une fonction d’utilité qui permet de sélectionnerles fournisseurs de services. Nous proposons également une versionaméliorée exploitant un cache distribué de données et un mécanismeproactif de composition de services exploitant les profils d’intérêt desutilisateurs. / This thesis is related to the domain of Ubiquitous computing and Internet ofThings (IoT), and focuses on networks that can be formed spontaneously bymobile or fixed devices. These devices can be connected using aninfrastructure, or in a peer-to-peer mode using ad hoc communications.Connection disruptions may occur in the network frequently andunpredictably. These connection disruptions can be problematic when a givendevice tries to access remote resources provided by other devices, or when ittries to offer its own resources to these ones.Opportunistic computing extends the paradigm of opportunistic networkingby abstracting local resources as services accessible remotely using theprotocols of opportunistic networking that implement the "store, carry andforward" principle.In this thesis, we focus on service composition in order to combineelementary services and offer new, rich and high level composite services tousers. Service composition can be a very difficult task to perform inopportunistic networks due to connection disruptions. In this thesis, we propose a solution to compose services using twostrategies: orchestration and choreography. This solution also relies on autility function that selects service providers. We also propose an optimizedversion of our solution that exploits a distributed cache of data and aproactive service composition mechanism based on the user interest profile.
32

Dynamic Composition of Service Specific Overlay Networks

Al Ridhawi, Yousif January 2013 (has links)
Content delivery through service overlay networks has gained popularity due to the overlays’ abilities to provide effective and reliable services. Inefficiencies of one-to-one matching of user requirements to a single service have given rise to service composition. Customized media delivery can be achieved through dynamic compositions of Service Specific Overlay Networks (SSONs). However, the presence of SSONs in dynamic environments raises the possibility of unexpected failures and quality degradations. Thus constructing, managing, and repairing corrupted service paths are challenging dilemmas. This thesis investigates the problem of autonomous SSON construction and management and identifies the drawbacks of current approaches. A novel multi-layered, autonomous, self-adaptive framework for constructing SSONs is presented. The framework includes a Hybrid Service Overlay Network layer (H-SON). The H-SON is a dynamic hybrid overlay dedicated to service composition for multimedia delivery in dynamic networks. Node placement in the overlay depends on the node’s stability, types and quality of provided services. Changes in stability and QoS of service nodes are reflected by dynamic re-organizations of the overlay. The H-SON permits fast and efficient searches for component services that meet client functional and quality expectations. Self-managed overlay nodes coordinate their behaviors to formulate a service composition path that meets the client’s requirements. Two approaches are presented in this work. The first illustrates how SSONs are established through dynamically adaptable MS-designed plans. The imprecise nature of nonfunctional service characteristics, such as QoS, is modeled using a fuzzy logic system. Moreover, semantic similarity evaluations enable us to include, in compositions, those services whose operations match, semantically, the requirements of the composition plan. Plan-based composition solutions restrict service discovery to defined abstract models. Our second composition approach introduces a semantic similarity and nearness SSON composition method. The objective is to free service nodes from the adherence to restrictive composition plans. The presented work illustrates a service composition solution that semantically advances service composition paths towards meeting users’ needs with each service hop while simultaneously guaranteeing user-acceptable QoS levels. Simulation results showcase the effectiveness of the presented work. Gathered results validate the success of our service composition methods while meeting user requirements.
33

Web Service Composition Compatibility : adaptation in the presence of Business Protocol Evolution / Compatibilité de la composition de services Web : adaptation suite à l’évolution des protocoles métier

Eslamichalandar, Maryam 19 December 2013 (has links)
Avec l’utilisation croissante d’architectures logicielles indépendantes de la plate-forme et du langage dans le paradigme de l’architecture orientée services (SOA), la technologie de services web permet l’interopérabilité dynamique et flexible des processus métiers aussi bien au niveau intra qu’inter-organisationnel. Bien que la normalisation des services web permet de réduire l’hétérogénéité et rend plus facile leur interopérabilité, il y a toujours besoin de vérifier leur compatibilité en particulier dans le contexte inter-entreprises. Deux services sont compatibles si une collaboration entre eux est accomplie avec succès et que chacun puisse atteindre ses résultats attendus (états finaux). L’approche typique devant permettre à des services incompatibles d’interagir correctement est l’adaptation du service. L’adaptation consiste dans ce contexte à faire face principalement aux discordances relevées au niveau des interfaces de service (incompatibilités entre signatures de services) ainsi qu’aux discordances qui ont lieu au niveau des protocoles métiers (incompatibilité dans l’ordre des messages échangés entre services). On distingue deux principales techniques d’adaptation: modification de service ou synthèse d’un composant adaptateur. L’adaptation en termes de modification de service exige l’application de certaines mesures d’optimisation pour supporter les spécifications du service partenaire. Dans le cas où l’adaptation traite de la création d’un adaptateur, un composant autonome modère les interactions entre les deux services de sorte que l’interopérabilité soit obtenue. En d’autres termes, l’adaptateur compense les différences entre interfaces de services par conversion de données (c’est-à-dire par transformation de message) et celles entre protocoles métiers en réorganisant les échanges de messages ou en générant un message manquant.Nous nous concentrons ici sur le problème de la reconfiguration dynamique de l’adaptateur en presence d’évolution de protocols métiers. Après avoir traité de la vérification d’un adaptateur en exploitant des techniques structurelles existantes développées dans le cadre de la théorie des réseaux de Petri, nous établissons une identification des patrons de mise à jour d’adaptateurs ainsi que la mise en correspondance de ces patrons avec les différents types d’évolutions possibles au niveau des protocoles métiers des services web. Ce travail a abouti à la proposition d’un algorithme permettant, d’une part de détecter les patrons d’évolution adéquats suite à une évolution d’un des protocoles métier des services partenaires et, d’autre part et sous certaines conditions, la mise à jour à la volée de la specification du nouvel adaptateur obtenu ainsi que sa verification.Enfin, les expérimentations réalisées sur un prototype montrent les avantages en termes de temps et de coût de l'approche dynamique proposée par rapport aux méthodes statiques conduisant systématiquement à la regeneration complète de l’adaptateur. / The advent of Web service technologies in the paradigm of Service oriented architecture (SOA) enables dynamic and flexible interoperation of distributed business processes within and across organization boundaries. One of the challenges in working with heterogeneous and autonomous Web services is the need to ensure their interoperability and compatibility. The typical approach for enabling incompatible services to interact is service adaptation. The need for adaptation in Web services comes from the heterogeneity at the levels of service interface and business protocol. The service interface incompatibilities include service signature mismatches (e.g., message and operation name, number; the type of input/output message parameters of operations; and the parameter value constraint). The mismatches at the business protocol (or service behavior) level arise from the order constraints that services impose on messages exchanges (e.g., deadlock where both partner services are mutually waiting to receive some message from the other, and unspecified reception in which one service sends a message while the partner is not expecting it). In service interaction through adaptation, an adapter mediates the interactions between two services with potentially different interfaces and business protocols such that the interoperability is achieved, i.e., adapter compensates for the differences between their interfaces by data mappings, and between their business protocols by rearranging the messages exchanges or generating a missing message. In this dissertation, we focus on how to cope with the dynamic evolution of business protocol P of a given service (i.e., P is changed to P') that is adapted by an adapter in the context of service interaction. Web service specifications constantly evolve. For variety of reasons, service providers may change their business protocols. Therefore, it is important to understand the potential impacts of the changes arising from the evolution of service business protocol on the adapter.We present an approach to automatically detect the effects of business protocols evolution on the adapter and, if possible, to suggest fixes to update the specification of adapter on-the-fly. Besides, we propose a technique to verify the correctness of new adapter which is dynamically re-configured. Finally, we describe a prototype tool where experimentations show the benefits of proposed approach in terms of time and cost compared to the static methods aiming for complete regeneration of adapter or manual inspection and adaption of the adapter with respect to changes in the business protocols.
34

Gestion sensible au métier des processus à base de services / Business environment-aware management of service-based business processes

Bouchaala Charfeddine, Olfa 30 September 2016 (has links)
Face à un environnement métier très dynamique, les entreprises expriment un grand besoin de gestion de leurs processus métiers de point de vue métier. Il existe trois types d’approche de gestion sensible aux changements de l’environnement métier : à savoir les approches impératives, déclaratives et hybrides. Les approches déclaratives sont très flexibles. Cependant, elles sont très couteuses en termes de temps. En contre partie, les approches impératives sont très efficaces mais trop rigide. Les approches hybrides, à leur tour, essaient de concilier entre les approches impératives et déclaratives afin d’augmenter le niveau concurrentiel des entreprises. Néanmoins, elles nécessitent un effort d’alignement entre la logique métier et la logique du processus. En outre, nous constatons que certaines approches ne sont pas faisables en pratique puisqu’ils n’utilisent pas les standards des processus.De plus, l’efficacité et la flexibilité sont antagonistes. Par conséquent, dans cette thèse, nous nous intéressons à la gestion sensible au métier visant à : (1) concilier les techniques déclaratives et les techniques impératives en une approche hybride pour tirer profit de leurs avantages, (2) préserver les standards des processus, et (3) minimiser l'effort des concepteurs. Nous avons ainsi proposé une nouvelle approche hybride pour la gestion des processus métiers. Nous avons modélisé la gestion d’un processus métier par un processus de gestion connecté au premier qui permet de le superviser et le configurer. Ce processus de gestion est généré grâce à une modélisation sémantique des relations entre les processus métiers, les services et l’environnement métier. Nous avons également implémenté cette approche et l'évaluer en comparaison avec les approches existantes de gestion sensible aux changements de l'environnement métier / Continuous business environment changes urge companies to adapt their processes from a business environment point of view. Indeed, companies struggle to find a balance between adapting their processes and keeping competitiveness. While the imperative nature of business processes is too rigid to adapt them at run-time, the declarative one of the purely rule based business processes is, however, very time consuming. Hybrid approaches in turn try to reconcile between these approaches aiming to reach the market requirements. Nevertheless, they also need an effort for aligning business logic and process logic. Therefore, in this thesis, we focus on business environment-aware management of service-based business processes aiming at conciliating imperative and declarative approaches. Our challenge is to develop a hybrid management approach that preserves industry standards to describe and to manage SBPs as well as minimizes designers’ efforts. Based on a semantic modeling of business environment, business processes as well as their relationships, and a control dependency analysis of business processes, we are able to synthesize a controller, itself modeled as a process, connected to the business process to be monitored and configured at run-time. We also validated the feasibility of our management approach by implementing the framework Business Environment-Aware Management for Service-based Business processes (BEAM4SBP). Experimentations show the efficiency of our approach with respect to other BEAM approaches
35

User-Centered Design of Translation Systems / 翻訳システムのユーザー中心設計

Shi, Chunqi 24 September 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第17921号 / 情博第503号 / 新制||情||89(附属図書館) / 30741 / 京都大学大学院情報学研究科社会情報学専攻 / (主査)教授 石田 亨, 教授 田中 克己, 教授 黒橋 禎夫 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
36

Policy-Aware Parallel Execution of Composite Services / 複合サービスのポリシーアウェアな並列実行

Mai, Xuan Trang 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第19855号 / 情博第606号 / 新制||情||105(附属図書館) / 32891 / 京都大学大学院情報学研究科社会情報学専攻 / (主査)教授 石田 亨, 教授 吉川 正俊, 教授 岡部 寿男 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
37

Exploring Service Composition and Financing Among Rural LHDs

Meit, Michael, Beatty, Kate E., Heffernan, Megan 09 May 2018 (has links)
No description available.
38

Exploring Differences between Urban and Rural LHDs: Service Composition and Financing

Meit, Michael, Beatty, Kate E., Heffernan, Megan 10 July 2018 (has links)
No description available.
39

Trust-Based Service Management for Service-Oriented Mobile Ad Hoc Networks and Its Application to Service Composition and Task Assignment with Multi-Objective Optimization Goals

Wang, Yating 11 May 2016 (has links)
With the proliferation of fairly powerful mobile devices and ubiquitous wireless technology, traditional mobile ad hoc networks (MANETs) now migrate into a new era of service-oriented MANETs wherein a node can provide and receive service from other nodes it encounters and interacts with. This dissertation research concerns trust management and its applications for service-oriented MANETs to answer the challenges of MANET environments, including no centralized authority, dynamically changing topology, limited bandwidth and battery power, limited observations, unreliable communication, and the presence of malicious nodes who act to break the system functionality as well as selfish nodes who act to maximize their own gain. We propose a context-aware trust management model called CATrust for service-oriented ad hoc networks. The novelty of our design lies in the use of logit regression to dynamically estimate trustworthiness of a service provider based on its service behavior patterns in a context environment, treating channel conditions, node status, service payoff, and social disposition as 'context' information. We develop a recommendation filtering mechanism to effectively screen out false recommendations even in extremely hostile environments in which the majority recommenders are malicious. We demonstrate desirable convergence, accuracy, and resiliency properties of CATrust. We also demonstrate that CATrust outperforms contemporary peer-to-peer and Internet of Things trust models in terms of service trust prediction accuracy against collusion recommendation attacks. We validate the design of trust-based service management based on CATrust with a node-to-service composition and binding MANET application and a node-to-task assignment MANET application with multi-objective optimization (MOO) requirements. For either application, we propose a trust-based algorithm to effectively filter out malicious nodes exhibiting various attack behaviors by penalizing them with trust loss, which ultimately leads to high user satisfaction. Our trust-based algorithm is efficient with polynomial runtime complexity while achieving a close-to-optimal solution. We demonstrate that our trust-based algorithm built on CATrust outperforms a non-trust-based counterpart using blacklisting techniques and trust-based counterparts built on contemporary peer-to-peer trust protocols. We also develop a dynamic table-lookup method to apply the best trust model parameter settings upon detection of rapid MANET environment changes to maximize MOO performance. / Ph. D.
40

Composição de serviços em ambientes pervasivos: um modelo de referência. / Services composition in pervasive environments: a reference model.

Zuñiga Torres, Juan Carlos 17 June 2013 (has links)
Ambientes Pervasivos são ambientes povoados por diversos dispositivos (sensores, atuadores, etc.) e aplicações de software (locais ou distribuídas) incorporadas nestes ambientes físicos de forma transparente para o usuário. Ambientes deste tipo devem ser capazes de interagir e satisfazer as requisições do usuário de forma autônoma e transparente. Nesse sentido, um dos maiores desafios de pesquisa em ambientes pervasivos é a de estabelecer mecanismos automáticos para compor, de forma dinâmica, funcionalidades que satisfaçam as requisições dos usuários. Nesse sentido, nós partimos da hipótese que mecanismos automáticos de interação entre ambientes e usuários podem ser abordados como um problema de composição automática de serviços em ambientes pervasivos. Portanto, nossa proposta é desenvolver um modelo referência, a partir do qual podem ser implementados sistemas que permitam ao ambiente pervasivo interagir com o usuário de forma natural, automática e dinâmica. Desta forma, o sistema de composição de serviços gerencia e automatiza o processo de resolução de requisições feitas pelo usuário (de forma implícita e/ou explicita) através das funcionalidades (serviços) disponíveis no ambiente ou através de novas funcionalidades criadas pelo processo de composição. Para tal fim, este trabalho apresenta um Modelo de Referência que permita projetar, implementar e avaliar sistemas de composição de serviços que gerenciem e automatizem o processo de interação em diversos tipos de ambientes pervasivos. Nossa proposta traz vantagens como: o baixo acoplamento e a interoperabilidade, isto porque é possível selecionar, integrar e reutilizar de forma eficiente e efetiva serviços heterogêneos provenientes de diversos tipos de dispositivos e/ou aplicações. Além disso, o modelo ontológico WSMO (Web Services Modelling Ontology) nos permite descrever semanticamente as capacidades dos serviços como também as informações contextuais presentes no ambiente, o que torna nosso sistema mais perto de um ambiente pervasivo real como o idealizado por Mark Weiser. / Pervasive environments are populated by several devices (sensors, actuators, etc.) and software applications (local or distributed) incorporated these physical environments transparently to the user. Environments of this type should be able to interact and process user requests autonomously and transparently. In this sense, one of the biggest research challenges in pervasive environments is to establish automatic mechanisms to compose dynamically, features that meet the user requirements. In this sense, we set the hypothesis that automatic mechanisms of interaction between users and environments can be addressed as a problem of automatic composition of services in pervasive environments. Therefore, our proposal is to develop a reference model, from which systems can be implemented to enable the pervasive environment interact with the user in a natural, automatic and dynamic. Thus, the system service composition management and automates the process of resolving requests made by the user (implicitly and / or explicitly) through the functionality (services) available in the environment or through new features created by the process of composition. To this end, this paper presents a Reference Model that allows to design, implement and evaluate systems of composition of services that manage and automate the interaction process in different types of pervasive environments. Our proposal brings benefits such as loose coupling and interoperability, because it is possible to select, integrate and reuse in an efficient and effective heterogeneous services from different types of devices and / or applications. Furthermore, the ontological model WSMO (Web Services Modeling Ontology) allows us to semantically describe the capabilities of the services as well as contextual information in the environment, which makes our system closer to a real pervasive environment as conceived by Mark Weiser.

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