Dissertations / Theses: 'Web services adaptation'

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Wong, Ka Wah. "Web services adaptation by using Web application wrapper /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?COMP%202004%20WONG.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.
Includes bibliographical references (leaves 68-70). Also available in electronic version. Access restricted to campus users.

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Iyer, Anand. "Evaluation and Adaptation of Web Services." Queensland University of Technology, 2003. http://eprints.qut.edu.au/15813/.

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One of the main aims of Component adaptation [Szy97] is to help application developers reuse components so that they can plug-in third party components into their application. This research concentrates on this type of adaptation but in the context of Web Services. Web Services are becoming increasingly popular. Web Services often ﬁt the requirements of being a component, and can be reused in a very similar manner. Hence there is a requirement for adaptation of Web Services just as there is the need for adaptation of software components. There are now quite a few adaptation techniques, but few of them have identiﬁed adaptation techniques for Web Services. This approach to adaptation allows for the modiﬁcation of data and behaviour of existing Web Services. The approach to adaptation uses eXtensible Stylesheet Language (XSL) transformation applied to the message passed between Web Services. These messages are commonly in XML format, hence XSL can be used to modify them. The application of the transformation is guided by a speciﬁcation written in XML. The adaptation is executed by a generic runtime system that uses these speciﬁcations which are referred to as Guiding Speciﬁcations. This has been demonstrated by way of a motivating real world example implemented on the .Net platform. It is shown how an adapter can be speciﬁed using a simplistic Guiding Speciﬁcation and related XSLT documents. This allows the implementation to work more efficiently than hand coding each adapter. It is the underlying generic runtime support that provides much of this beneﬁt. Component based software engineering (CBSE) constructs applications by assembling components together, CBSE has been of great help to application developers due to the very fact that tailor made components can be purchased from third party vendors and can be plugged-in to a system to form a working application. But in practice 'as-is' reuse is very unlikely to occur, and most components need to be changed in some way to match the requirements of the application architecture and other components. The process of changing thecomponent for use in a particular application is often referred to as Component Adaptation.

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Lawson, K. L. "Knowledge-based Web services for context adaptation." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1444447/.

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The need for higher value, reliable online services to promote new Internet-based business models is a requirement facing many technologists and business leaders. This need coupled with the trend towards greater mobility of networked devices and consumers creates significant challenges for current and future systems developers. The proliferation of mobile devices and the variability of their capabilities present an overwhelming number of options to systems designers and engineers who are tasked with the development of next generation context adaptive software services. Given the dynamic nature of this environment, implementing solutions for the current set of devices in the held makes an assumption that this deployment situation is somehow fixed this assumption does little to support the future and longer term needs within the marketplace. To add to the complexity, the timeframes necessary to develop robust and adaptive online software services can be long by comparison, so that the development projects and their resources are often behind on platform support before the first release is launched to the public. New approaches and methodologies for engineering dynamic and adaptive online services will be necessary and, as will be shown, are in fact mandated by the regulation imposed by service level guarantees. These new techniques and technology are commercially useless unless they can be used in engineering practice. New context adaptation processes and architectures must be capable of performing under strict service level agreements those that will undoubtedly govern future business relationships between online parties. This programme of engineering study and research investigates several key issues found in the emerging area of context adaptation services for online mobile networks. As a series of engineering investigations, the work described here involves a wider array of technical activity than found in traditional doctoral work and this is reflected throughout the dissertation. First, a clear definition of industrial motivation is stated to provide the engineering foundation. Next, the programme focuses on the nature of contextual adaptation through product development projects. The development process within these projects results in several issues with the commercial feasibility of the technology. From this point, the programme of study then progresses through the lifecycle of the engineering process, investigating at each stage the critical engineering challenges. Further analysis of the problems and possible solutions for deploying such adaptive solutions are reviewed and experiments are undertaken in the areas of systems component and performance analysis. System-wide architectural options are then evaluated with specific interest in using knowledge-base systems as one approach to solving some of the issues in context adaptation. The central hypothesis is that due to the dynamic nature of context parameters, the concept of a mobile device knowledge base as a necessary component of an architectural solution is presented and justified through prototyping efforts. The utility of web ontologies and other "soft computing" technologies on the nature of the solution are also examined through the review of relevant work and the engineering design of the demonstration system. These technology selections are supported directly by the industrial context and mission. In the final sections, the architecture is evaluated through the demonstration of promising techniques and methods in order to confirm understanding and to evaluate the use of knowledge-bases, AI and other technologies within the scope of the project. Through the implementation of a context adaptation architecture as a business process workflow, the impact of future trends of device reconfiguration are highlighted and discussed. To address the challenge of context adaptation in reconftgurable device architectures, an evolutionary computation approach is then presented as a means to provide an optimal baseline on which a service may execute. These last two techniques are discussed and new designs are proposed to specifically address the major issues uncovered in timely collection and evaluation of contextual parameters in a mobile service network. The programme summary and future work then brings together all the key results into a practitioner's reference guide for the creation of online context adaptive services with a greater degree of intelligence and maintainability while executing with the term of a service level agreement.

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Wang, Kenneth W. S. "Interface adaptation for conversational services." Queensland University of Technology, 2008. http://eprints.qut.edu.au/18465/.

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The proliferation of services on the web is leading to the formation of service ecosystems wherein services interact with one another in ways not foreseen during their development or deployment. This means that over its lifetime, a service is likely to be reused across multiple interactions, such that in each of them a different interface is required from it. Implementing, testing, deploying, and maintaining adapters to deal with this multiplicity of required interfaces can be costly and error-prone. The problem is compounded in the case of services that do not follow simple request-response interactions, but instead engage in conversations comprising arbitrary patterns of message exchanges. A key challenge in this setting is service mediation: the act of retrofitting existing services by intercepting, storing, transforming, and (re-)routing messages going into and out of these services so they can interact in ways not originally foreseen. This thesis addresses one aspect of service mediation, namely service interface adaptation. This problem arises when the interface that a service provides does not match the interface that it is expected to provide in a given interaction. Specifically, the thesis focuses on the reconciliation of mismatches between behavioural interfaces, that is, interfaces that capture ordering constraints between message exchanges. We develop three complementary proposals. Firstly, we propose a visual language for specifying adapters for conversational services. The language is based on a an algebra of operators that are composed to define links between provided-required interfaces. These expressions are fed into an execution engine that intercepts, buffers, transforms and forwards messages to enact the adapter specification. Secondly, we endow such adapter specifications with a formal semantics defined in terms of Petri nets. The formal semantics is used to statically check the correctness of adapter specifications. Finally, we propose an alternative approach to service interface adaptation that does not require hard-wired links between provided and required interfaces. This alternative approach is based on the definition of mapping rules between message types, and is embodied in an adaptation machine. The adaptation machine sits between pairs of services and manipulates the exchanged messages according to a repository of mapping rules. The adaptation machine is also able to detect deadlocks and information loss at runtime.

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Aschoff, Rafael Roque. "A proactive adaptation framework for composite web services." Thesis, City University London, 2014. http://openaccess.city.ac.uk/13548/.

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Service orientation is a design paradigm consisting of a set of principles governed by a service-oriented architecture (SOA) to support the creation of software systems as a composition of interoperable services. The ability to effectively compose services is not a trivial task due to the dynamic nature of the execution environment of service compositions. In this context, dynamic service selection and composition is a critical requirement and one of the major research challenges for service-based systems. This research investigates the identification, detection and prediction of the need for adaptation as well as ways to autonomously reconfigure the service composition during its execution time in order to improve service reliability and conformance with systems requirements and policies. We propose a framework for proactive adaptation of service compositions that extends current approaches for dynamic service composition by proactively and individually identifying the need for adaptation for each parallel running instance of service composition while avoiding unnecessary changes and distributing load request among different service operations when necessary. Our framework has been tested and validated using different prototypes implemented in both simulated and real environments. The results were favourable with the research objectives and indicates a major gain in the use of the proposed proactive techniques in the execution and adaptation of web service compositions.

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Baptista, Adérito Herculano Sarmento. "Dynamic adaptation of interaction models for stateful web services." Master's thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/12042.

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Dissertação para obtenção do Grau de Mestre em Engenharia Informática
Wireless Sensor Networks (WSNs) are accepted as one of the fundamental technologies for current and future science in all domains, where WSNs formed from either static or mobile sensor devices allow a low cost high-resolution sensing of the environment. Such opens the possibility of developing new kinds of crucial applications or providing more accurate data to more traditional ones. For instance, examples may range from large-scale WSNs deployed on oceans contributing to weather prediction simulations; to high number of diverse Sensor devices deployed over a geographical area at different heights from the ground for collecting more accurate data for cyclic wildfire spread simulations; or to networks of mobile phone devices contributing to urban traffic management via Participatory Sensing applications. In order to simplify data access, network parameterisation, and WSNs aggregation, WSNs have been integrated in Web environments, namely through high level standard interfaces like Web services. However, the typical interface access usually supports a restricted number of interaction models and the available mechanisms for their run-time adaptation are still scarce. Nevertheless, applications demand a richer and more flexible control on interface accesses – e.g. such accesses may depend on contextual information and, consequently, may evolve in time. Additionally, Web services have become increasingly popular in the latest years, and their usage led to the need of aggregating and coordinating them and also to represent state in between Web services invocations. Current standard composition languages for Web services (wsbpel,wsci,bpml) deal with the traditional forms of service aggregation and coordination, while WS-Resource framework (wsrf) deals with accessing services pertaining state concerns (relating both executing applications and the runtime environment). Subjacent to the notion of service coordination is the need to capture dependencies among them (through the workflow concept, for instance), reuse common interaction models, e.g. embodied in common behavioural Patterns like Client/Server, Publish/- Subscriber, Stream, and respond to dynamic events in the system (novel user requests, service failures, etc.). Dynamic adaptation, in particular, is a pressing requirement for current service-based systems due to the increasing trend on XaaS ("everything as a service") which promises to reduce costs on application development and infrastructure support, as is already apparent in the Cloud computing domain. Therefore, the self-adaptive (or dynamic/adaptive) systems present themselves as a solution to the above concerns. However, since they comprise a vast area, this thesis only focus on self-adaptive software. Concretely, we propose a novel model for dynamic interactions, in particular with Stateful Web Services, i.e. services interfacing continued activities. The solution consists on a middleware prototype based on pattern abstractions which may be able to provide (novel) richer interaction models and a few structured dynamic adaptation mechanisms, which are captured in the context of a "Session" abstraction. The middleware was implemented and uses a pre-existent framework supporting Web enabled access to WSNs, and some evaluation scenarios were tested in this setting. Namely, this area was chosen as the application domain that contextualizes this work as it contributes to the development of increasingly important applications needing highresolution and low cost sensing of environment. The result is a novel way to specify richer and dynamic modes of accessing and acquiring data generated by WSNs.
Este trabalho foi parcialmente financiado pelo Centro de Informática e Tecnologias da Informação (CITI), e pela Fundação para a Ciência e a Tecnologia (FCT / MCTES) em projectos de investigação

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Eslamichalandar, Maryam. "Web Service Composition Compatibility : adaptation in the presence of Business Protocol Evolution." Thesis, Paris, CNAM, 2013. http://www.theses.fr/2013CNAM0998/document.

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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

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Motahari, Nezhad Hamid Reza Computer Science &amp Engineering Faculty of Engineering UNSW. "Discovery and adaptation of process views." Publisher:University of New South Wales. Computer Science & Engineering, 2008. http://handle.unsw.edu.au/1959.4/41026.

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Business process analysis and integration are key endeavours for today's enterprises. Recently, Web services have been widely adopted for the implementation and integration of business processes within and across enterprises. In this dissertation, we investigate the problem of enabling the analysis of service interactions, in today's enterprises, in the context of business process executions, and that of service integration. Our study shows that only fraction of interactions in the enterprise are supported by process-aware systems. However, enabling above-mentioned analyses requires: (i) a model of the underlying business process to be used as a reference for the analysis, and (ii) the ability to correlate events generated during service interactions into process instances. We refer to a process model and the corresponding process instances as a "process view". We propose the concept of process space to refer to all process related information sources in the enterprise, over which various process views are defined. We propose the design and development of a system called "process space discovery system" (PSDS) for discovering process views in a process space. We introduce novel approaches for the correlation of events into process instances, focusing on the public processes of Web services (business protocols), and also for the discovery of the business protocol models from the process instances of a process view. Analysis of service integration approaches shows that while standardisation in Web services simplifies the integration in the communication level, at the higher levels of abstractions (e.g., services interfaces and protocol models) services are still open to heterogeneities. We characterise the mismatches between service interfaces and protocol specifications and introduce "mismatch patterns" to represent them. A mismatch pattern also includes an adapter template that aims at the resolution of the captured mismatch. We also propose semi-automated approaches for identifying the mismatches between interface and protocol specifications of two services. The proposed approaches have been implemented in prototype tools, and experimentally validated on synthetic and real-world datasets. The discovered process views, using PSDS, can be used to perform various analyses in an enterprise, and the proposed adaptation approach facilitates the adoption of Web services in business process integration.

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Kazi, Aoul Zakia Aoul. "Une archietecture orientée services pour la fourniture de documents multimédia composés adaptables." Phd thesis, Télécom ParisTech, 2008. http://pastel.archives-ouvertes.fr/pastel-00004172.

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L'échange de documents multimédia composés de plusieurs médias élémentaires tels que des vidéos, des images ou du texte, est l'une des applications les plus populaires d'Internet. Idéalement, tout usager d'Internet devrait pouvoir accéder à ces contenus et les recevoir dans un format adapté au contexte dans lequel il travaille. Un contexte utilisateur peut être défini par les caractéristiques personnelles de l'utilisateur (ex : sa langue parlée, son handicap et ses centres d'intérêt), ses préférences de présentation des contenus multimédia (ex : son lecteur multimédia préféré ou la taille d'image souhaitée), les capacités de son terminal (ex : la taille de l'écran du terminal ou les lecteurs multimédia présents) et les caractéristiques de son réseau d'accès (ex : la bande passante). Compte tenu de la combinatoire des éléments de contexte, il n'est pas envisageable de fournir autant de versions des documents multimédia que de contextes possibles : l'adaptation des contenus est donc nécessaire. L'accroissement des utilisateurs des terminaux à capacités réduites tels que les assistants personnels (par ex. PDA) exclut une adaptation côté client (ou utilisateur final). L'adaptation, côté source du document multimédia, nécessite l'implémentation de modules supplémentaires qui n'est pas toujours possible et qui peut créer une charge supplémentaire indésirable. L'adaptation par un ou plusieurs intermédiaires répond le mieux aux besoins de passage à l'échelle et d'extensibilité. Une machine intermédiaire est un nœud inséré entre le client et le serveur et dédié, par exemple, à la découverte ou à l'adaptation de services (ex : réduction de la taille d'une image ou traduction et insertion de sous-titres au sein d'une vidéo). L'intermédiation ainsi réalisée apporte une valeur ajoutée en évitant de charger l'utilisateur final et la source du document de tâches spécifiques consommatrices de ressources sans rapport direct avec le service final offert. Cette approche est celle qui est prise dans la plupart des solutions existantes. Celles-ci utilisent des intermédiaires dédiés. Il en résulte une configuration d'adaptation figée ne garantissant pas la gestion de nouvelles techniques d'adaptation (ex : les adaptations relatives à l'handicap) et ne passant pas à l'échelle. Certaines solutions, basées sur ce même modèle, intègrent l'adaptation distribuée en répartissant la charge entre les intermédiaires qui réalisent l'adaptation. Elles ne traitent cependant pas la gestion dynamique des adaptateurs qui consiste à aller chercher des adaptateurs dans le réseau, les composer et les recomposer dynamiquement en cas de disparition. Elles ne traitent pas non plus l'adaptation des documents multimédia composés qui demande un effort supplémentaire d'analyse du document et de synchronisation des médias élémentaires le composant. La première contribution de cette thèse est la conception d'une architecture appelée PAAM (pour Architecture for the Provision of AdAptable Multimedia composed documents) qui a pour but d'adapter des documents multimédia composés au contexte des usagers. L'une des originalités de cette architecture est de mettre en place une adaptation distribuée sur différents nœuds du réseau en évitant de confier l'adaptation à un serveur ou à un intermédiaire dédié. La plate-forme d'adaptation de PAAM intègre aussi bien des fournisseurs de services d'adaptation que des particuliers qui se porteraient volontaires pour exécuter des fonctions d'adaptation en donnant un peu de leurs ressources matérielles et logicielles. Les principaux éléments fonctionnels de PAAM sont : le gestionnaire du contexte utilisateur, le gestionnaire des documents multimédia composés, le planificateur et le gestionnaire d'adaptation. Le gestionnaire du contexte utilisateur et le gestionnaire des documents multimédia composés récupèrent, analysent et agrégent respectivement les informations contextuelles de l'utilisateur et les informations descriptives des documents multimédia. Le planificateur implémente un algorithme de prise de décision reposant sur des politiques d'adaptation. Ce planificateur produit un graphe d'adaptation, c'est-à-dire un ensemble d'adaptateurs organisés en parallèle ou en séquence. Ce graphe est utilisé en entrée du gestionnaire d'adaptation qui recherche ces adaptateurs là où ils se trouvent, les instancie, les compose, si nécessaire, et les recompose si un ou plusieurs adaptateurs disparaissent. Nous avons choisi d'utiliser les services Web pour implémenter PAAM afin qu'elle soit distribué, extensible, modulable, tolérante aux fautes et passant à l'échelle, répondant ainsi aux limitations des autres architectures d'adaptation. Cette solution technologique permet à PAAM de décrire des ressources d'adaptation, de les publier, de les rechercher et les instancier. Dans le cadre de la composition et de l'orchestration des services Web, nous présentons BPEL (Business Process Execution Language) et son éventuelle intégration au sein d'un gestionnaire d'adaptation pour gérer l'exécution d'un graphe d'adaptation. La seconde contribution de cette thèse est la gestion des adaptateurs (description, recherche et instanciation). Nous proposons, pour cela, une nomenclature incluant un grand nombre d'adaptateurs. Nous proposons aussi une description d'adaptateurs qui étend WSDL, et qui facilite la recherche, l'instanciation et la composition de ces ressources d'adaptation. Nous exposons par la suite le protocole de négociation et d'acceptation établi entre un gestionnaire d'adaptation et un adaptateur permettant de déterminer si cet adaptateur peut réaliser l'adaptation ou non. PAAM gérant l'adaptation distribuée sur différents nœuds du réseau, susceptibles de se déconnecter à chaque instant, nous proposons des solutions pour gérer les déconnexions dans PAAM afin de lui procurer un aspect dynamique. Afin de démontrer la faisabilité de notre architecture, nous implémentons une chaîne d'adaptation complète incluant les principales fonctionnalités de PAAM : le gestionnaire du contexte utilisateur, le gestionnaire des documents multimédia composés, le planificateur et le gestionnaire d'adaptation. Nous présentons, par la suite, une étude des coûts induits par notre implémentation de PAAM et des tests de performances qui montrent que l'utilisation des services Web n'introduit pas de surcoûts significatifs par rapport au gain obtenu en distribuant l'adaptation sur différents nœuds. Pour conclure, parce qu'elle permet de gérer une grande variété d'adaptateurs de manière distribuée, l'architecture PAAM répond bien aux limitations des architectures d'adaptation basées sur une configuration client/serveur. L'intérêt de cette approche est la possibilité d'étendre et d'enrichir le système d'adaptation et de le déployer à large échelle tout en garantissant sa robustesse.

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Lopez-Velasco, Céline. "Sélection et composition de services Web pour la génération d'applications adaptées au contexte d'utilisation." Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00388991.

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Ce travail se situe dans le domaine de la conception des applications à base d'architecture orientée services adaptées au contexte d'utilisation. Ce type d'architecture permet les échanges entre les fournisseurs de services et les clients qui conçoivent de telles applications. Afin que les clients trouvent le service correspondant aux mieux à leurs besoins, les services doivent être décrits par leur fournisseur selon un processus standard. Ceci permet à ces services d'être réutilisés, découverts et composés. La combinaison de ces services doit apporter un résultat adapté au contexte d'utilisation (l'utilisateur, la localisation, le temps, et le dispositif utilisé). Nous proposons dans ce travail une solution qui englobe les processus de description, de recherche, et de composition de services, en ajoutant de manière transversale l'adaptation au contexte d'utilisation.
Le standard de description de services Web WSDL ne permet qu'une représentation des aspects fonctionnels des services (méthode, paramètres échangés, et protocole d'accès). Afin de faciliter les étapes de recherche et de sélection effectuées par les clients, la représentation de services doit être enrichie des aspects liés au domaine d'application auquel les services sont dédiés, les aspects non fonctionnels (tels que la description du fournisseur et des contraintes d'exécution) et le contexte d'utilisation auquel les services s'adaptent. Le modèle de représentation de services Web proposé, appelé WSR-Model, fournit l'ensemble de ces catégories d'informations afin que les fournisseurs publient leurs services et que les clients réalisent les étapes de recherche et de sélection. Ce modèle est opérationnalisé via le système de représentation de connaissances par objets AROM qui implémente le registre de services Web, que nous nommons WSR.
La composition de services Web repose sur une description de la planification des services et sur l'exécution de cette planification. À ce jour, les solutions existantes ne prennent pas en compte l'évolutivité de la composition et la prise en compte de l'adaptation au contexte d'utilisation lors des phases de description et d'exécution de la composition. Nous proposons un modèle de composition de services Web, appelé ProbCWS, qui s'appuie sur les méthodes de résolution de problèmes à base de modèle de tâches. La définition de la composition est définie comme un problème à résoudre, dont les tâches de résolution de plus faible granularité sont des services Web. La plate-forme de génération d'applications adaptées, nommée GenAWS et intégrant ProbCWS, fournit aux clients un moyen de composer à la volée des applications adaptées. La mise en oeuvre de GenAWS est réalisée, entre autres, par le langage de résolution de problèmes AROMTasks, sous-jacent au système AROM.

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Soukkarieh, Bouchra. "Technique de l'internet et ses langages : vers un système d'information web restituant des services web sensibles au contexte." Toulouse 3, 2010. http://thesesups.ups-tlse.fr/978/.

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Un des grands besoins liés aux Systèmes d'Information orientés-Web est l'adaptation au contexte. Ce besoin vise à délivrer à l'utilisateur des Services Web pertinents non seulement par rapport à sa requête mais aussi par rapport à son contexte. Quand l'utilisateur se connecte à un Système d'Information Web, il lance d'abord sa requête cherchant les Services Web pertinents par rapport à cette requête, puis il choisit un de ces services et il commence l'interaction avec le service choisi. L'adaptation au contexte doit donc être prise en compte dans deux phases de l'architecture d'un tel système : la phase de recherche des Services Web et la phase d'interaction avec un Service Web. La plupart des travaux intéressés à ces deux problèmes ont une utilisation limitée de la notion de contexte. De plus, l'adaptation au contexte dans la phase d'interaction avec un Service Web est basée sur la sauvegarde de plusieurs versions des données du service afin de choisir la version adaptée au contexte, ce qui conduit à une surcharge du serveur. Pour répondre à ces besoins et pallier les manques des travaux, nous avons proposé une plateforme CA-WIS (Context Adaptation of Web Information Système). Par cette plateforme, nous avons présenté une démarche plus générale pour concevoir des Systèmes d'Information Web fournissant des Services Web sensibles au contexte. Nous avons intégré un modèle générique du contexte dans les deux phases de l'architecture de cette plateforme pour permettre à un utilisateur de recevoir d'une part des Services Web pertinents par rapport à son contexte, et d'autre part d'interagir avec un service sensible au contexte. Ce modèle générique concerne non seulement le contexte de l'utilisateur mais aussi le contexte du service. Afin d'assurer la généricité de contexte de l'utilisateur, nous avons proposé un algorithme de filtrage. Cet algorithme permet de ne garder que les préférences de l'utilisateur satisfaites avec les caractéristiques de son contexte. La réalisation du processus d'adaptation au contexte dans la phase de recherche des Services Web est basée sur les processus de filtrage et ré-ordonnancement des Services Web pour restituer à l'utilisateur une liste ordonnée des Services Web pertinents par rapport à son contexte. Afin de réaliser l'adaptation au contexte dans la phase d'interaction avec un service, nous nous somme basés sur une nouvelle méthodologie de modélisation des données. .
One of needs related to Web Information Systems is context adaptation. This need aims to deliver the user with Web services that are not relevant to his query but also to his context. In the classical architecture of the existing Web Information Systems, a user first launches his query and as a response, the system retrieves the Web Services relevant to this query, then he chooses one of these services and begins the interaction with the selected service. Therefore, context adaptation must be taken into account in two phases within these systems: at the Web Services querying phase and at the interaction phase with a Web Service. Most of the works interested in these two problems have limited the use of the context notion. Furthermore, the context adaptation during the interaction phase with a Web Service is based on saving several versions of the service data in order to choose a version that is appropriate to the context; this solution leads to overload the server. In order to meet these needs, we proposed a CA- WIS (Context Adaptation Web Information System) platform. Using this platform, we have presented a generic approach to design Web Information Systems providing context-aware Web Services. We integrated a generic context model in two phases of the architecture of this platform in order to allow a user to receive on one hand Web Services that are relevant to his context, and on the other hand to be able to interact with a context-aware Web Service. This generic model takes into consideration not only the user's context but also the service context. To ensure that the user context is generic, we have proposed a filtering algorithm. This algorithm allows keeping only the user's preferences satisfied with the characteristics of his context. The realization of the context adaptation process in the research phase of Web Services is based on the filtering and re-ordering of Web Services to return to the user a ranked list of the Web services that is relevant to his context. To achieve the context adaptation in the phase where users interact with a service, we have used a new data modeling methodology. The main advantage of using this methodology is to save the data only once with several structures, which can reduce the server overload. We have validated the CA-WIS platform through two prototypes. .

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Kongdenfha, Woralak Computer Science &amp Engineering Faculty of Engineering UNSW. "Pattern-based data and application integration in service oriented architectures." Awarded By:University of New South Wales. Computer Science & Engineering, 2009. http://handle.unsw.edu.au/1959.4/42600.

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The success of Web services comes from the benefits that it brings in reducing the cost and the time needed to develop data and applications by reusing them, and simplifying their integrations through standardization. However, standardization in Web services does not remove the need for adapters due to possible heterogeneity among service interface and protocol definitions. Moreover, the current service APIs are targeted toward professional programmers, but not accessible to a wider class of users without programming expertise, but would never the less like to build their own integrated applications. In this dissertation, we propose methods and tools to support both service developers and non-expert users in their data and application integration tasks. To support service developers, we propose a framework that enables rapid development of Web service adapters. We investigate particularly the problem of service adaptation focusing on business interface and protocol layers. Our study shows that many differences between business interfaces and protocols are recurring. We introduce mismatch patterns to capture these recurring differences and provide solutions to resolve them. We present the notion of adaptation aspects, which is based on the aspect-oriented programming paradigm, to enable rapid development and deployment of service adapters. We also present a comparative study between standalone and aspect-oriented adapters development. The study shows that the aspect-oriented approach is preferable in many cases, especially when adapters need to access internal states of services. The proposed approach is implemented in a prototype tool, which is used to illustrate how it simplifies adapters development through a case study. To support users without programming expertise, we propose a spreadsheet-based Web mashups development framework, which enables users to develop mashups in the popular spreadsheet environment. First, we provide a mechanism that makes structured data first class values of spreadsheet cells. Second, we propose a new component model that can be used to develop fairly sophisticated mashups, involving joining data sources and keeping spreadsheet data up to date. Third, to simplify mashup development, we provide a collection of spreadsheet-based mashup patterns that captures common Web data access and spreadsheet presentation functionalities. Users can reuse and customize these patterns to build spreadsheet-based Web mashups instead of developing them from scratch. Fourth, we enable users to manipulate structured data presented on spreadsheet in a drag-and-drop fashion. Finally, we have developed and tested a prototype tool to demonstrate the utility of the proposed framework.

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Balegh, Walid. "Communication and Adaptation in a Ubiquitous Environment." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-76624.

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Context awareness means sending the right information to the right user at the righttime. Context is our environment, which can be anything around us such as location,lights, noises etc. To make the context interact with our mobile devices or sensors,there must be protocols for communication and data formats for the “sent” or “received”contextual information so we can give very specific context information tothe user. Since this communication and adaptive part is not well understood, in thispaper we are interested in investigating the technology used for adaptation. We willalso explain how this technology works to adapt itself to changes in the environment.

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Billet, Yves-Gaël. "Adaptation dynamique d'applications multimédia à leur contexte d'exécution dans les réseaux du futur." Phd thesis, Université Jean Monnet - Saint-Etienne, 2012. http://tel.archives-ouvertes.fr/tel-00955366.

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L'objectif de cette thèse est d'apporter une réponse à la problématique d'adaptation automatique et dynamique des services numériques au sein des réseaux du futur (NGN). Pour cela, notre contribution s'articule autour d'un intergiciel qui prend en charge les fonctions de gestion du contexte pour les services numériques ; ceci pour permettre l'émergence de services numériques sensibles au contexte dans les réseaux du futur. L'originalité de ces travaux dans les NGN se situe dans le modèle de conception pour des services numériques sensibles au contexte où l'on découple la logique métier du service numérique de la logique de gestion du contexte. Plus spécifiquement nous définissons la notion de signature de contexte, propre à chaque service numérique, qui permet d'identifier les situations d'usage du service numérique et accompagne l'intergiciel dans le choix de la modalité d'exécution la plus performante. Elle est liée au service numérique sensible au contexte dès sa conception. Lors du déploiement du service dans le serveur d'applications, la signature de contexte est désolidarisée de la logique métier et se voit insérée dans la base de connaissance de l'intergiciel. La signature fait ainsi le lien entre l'intergiciel et le service numérique. Elle permet d'activer l'ensemble des fonctions de traitement du contexte que nous avons modélisées sous la forme d'une chaîne de traitement du contexte. Cette approche assure une séparation des deux logiques qui composent un service numérique sensible au contexte. Les concepteurs de tels services peuvent alors se concentrer sur le développement de la logique métier sans se soucier des fonctions de gestion du contexte

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Hussein, Ali Dina. "A social Internet of Things application architecture : applying semantic web technologies for achieving interoperability and automation between the cyber, physical and social worlds." Thesis, Evry, Institut national des télécommunications, 2015. http://www.theses.fr/2015TELE0024/document.

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Récemment, l'intégration entre les environnements informatiques et de réseautage a été largement promu pour fournir des services intelligents à des utilisateurs finaux ainsi que l'utilisation efficace des ressources. Cette convergence a ouvert la voie à l'émergence de l'internet des objets (IdO). Le paradigme de l'IdO repose principalement sur la fabrication d'objets, appelés les choses, disparaître et se tissent dans le tissu de notre vie de tous les jours pour nous soutenir dans l'accomplissement des activités quotidiennes. L'évolutivité et l'hétérogénéité sont parmi les principaux défis qui entravent la réalisation à grande échelle de services de l'IdO dans la vie quotidienne des utilisateurs. Afin de relever les défis de l'IdO, un nouveau volet de recherche est venu en avant dans la littérature comme une classe paradigmatique des Cyber-physiques systèmes sociaux (CSPR), qui est connu comme l'Internet social des choses (Siot). Le SIOT se fonde sur la notion soulignée par phénomène petite-monde où la structure sociale permettant relation sociale fondée sur la confiance entre les personnes et les objets, d'une manière qui ressemble à des services de réseaux sociaux traditionnels (SNS) est suggérée de relever les défis de l'IdO. Cependant, depuis SIOT hérite des caractéristiques de différents informatiques et de réseautage environnements (par exemple, l'IdO et SNS) cela, en fait, augmente la quantité et la variété des données contextuelles qui doit être manipulé pour Adaptive fourniture de services dans Siot, qui agit comme le principal défi adressé dans cette thèse. Autrement dit, dans cette thèse, nous proposons la notion de contexte cognitif lorsque, dans certaine situation spatio-temporelle, le raisonnement sur les aspects objectifs du cadre, ce qui représente l'environnement physique, avec le contexte subjective, qui représente les aspects comportementaux et sociaux, est considéré comme l'amélioration des services SIOT intelligence et la capacité d'adaptation aux besoins conjoncturels des utilisateurs. Nous envisageons technologies du Web sémantique pour déployer notre contexte cognitif proposé dans deux domaines d'application; sensible au contexte recommandation des tâches quotidiennes dans les maisons intelligentes et structure sociale dépendant de la situation des choses. Un prototype de preuve de concept a été développé pour chaque domaine d'application, dans le but de démontrer l'intégration harmonieuse des objets sur le Web pour la réalisation de certaines applications. Nos résultats empiriques montrent un niveau de service amélioré l'adaptabilité et la complexité en temps de fonctionner lors de l'application de notre contexte cognitif suggéré
The paradigm of the Social Internet of Things (SIoT) is being promoted in the literature to boost a new trend wherein the benefits of social network services are exhibited within the network of connected objects i.e., the Internet of Things (IoT). The novel user-friendly interaction framework of the SIoT opens the doors for enhancing the intelligence required to stimulate a shift in the IoT from a heterogeneous network of independently connected objects towards a manageable network of everything. In practice, achieving scalability within the large-scale and the heterogeneous paradigm of the IoT while maintaining on top of its user-friendly and intuitive services to bridge human-to-machine perceptions and encourage the technology’s adaptation is a major challenge which is hindering the realization and deployment of the IoT technologies and applications into people’s daily live. For the goal of handling IoT challenges, as well as improve the level of smart services adaptability to users’ situational needs, in this thesis, novel SIoT-based application architecture is provided. That is, Semantic Web Technologies are envisaged as a means to develop automated, value-added services for SIoT. While, interoperability and automation are essential requirement to seamlessly integrate such services into user life, Ontologies are used to semantically describe Web services with the aim of enabling the automatic invocation and composition of these services as well as support interactions across the cyber, physical and social worlds. On the other hand, handling the variety of contextual data in SIoT for intelligent decision making is another big challenge which is still in very early stages of research. In this thesis we propose a cognitive reasoning approach taking into consideration achieving situational-awareness (SA) in SIoT. This reasoning approach is deployed within two application domains where results show an improved level of services adaptability compared to location-aware services which are previously proposed in the literature

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Forte, Marcos. "Especificação de perfis e regras, baseada em ontologias, para adaptação de conteúdo na internet." Universidade Federal de São Carlos, 2006. https://repositorio.ufscar.br/handle/ufscar/335.

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Made available in DSpace on 2016-06-02T19:05:22Z (GMT). No. of bitstreams: 1 DissMF.pdf: 2025508 bytes, checksum: f2e422deb152e992fd87b135fec6cd65 (MD5) Previous issue date: 2006-08-21
The last decade was scenery of big transformations, among them the social revolution caused by Internet stand out, changing the way that people find information, communicate and buy products and services. Moreover, the convergence of telephony, informatics and consume electronic, supplies more and more mobile devices equipped with Internet access through wireless network. This changing caused a big problem to the Internet content available at Web: how the same content should be adjusted to different kinds of users witch have particular preferences, and be presented in mobile devices featured with a big diversity of functionalities? To solve this problem, many research proposals are been developed at content adaptation area. One challenge of this area is define, from a user request, witch adaptation services are necessary and these execute sequence. In order to have the best decision, delivery context and the available services have to be acknowledged. This information are described at profiles and rules, considering that nowadays the majority of proposed solutions are based in proprietary models and not compatibles among each other. As well, the discovery of services generally is strongly based on syntactic matching, what weak the discovery and composition of services. Intending to contribute with content adaptation area, this dissertation defines an ontology-based set of profiles and reused. Furthermore, shows how the rules have to be integrated with services profiles, providing a rules and profiles independent solution. Also are presented the benefits use of semantics at match and composition of services in an open environment such as the Web. The implementation and the case study of this proposition were based at a component-based content adaptation framework. With the purpose of extend its functionality, in order to support ontology, and others necessary functions, components were reused, adapted or created. This extensions made possible achieve the case study and the validation of proposed solution.
Esta última década foi cenário de grandes transformações, dentre estas destaca-se a revolução social que a Internet está promovendo, alterando a forma como as pessoas encontram informações, comunicam-se e compram produtos e serviços. Além disso, a convergência da telefonia, computação e eletrônica de consumo, está disponibilizando cada vez mais dispositivos móveis de acesso a Internet que se comunicam via redes sem fio. Essas mudanças causaram um grande problema para o conteúdo disponível na Web: como um mesmo conteúdo pode se adequar a diferentes tipos de usuário, que possuem suas próprias preferências, e ser apresentado em dispositivos móveis compostos por uma grande diversidade de características funcionais? Para resolver este problema, muitas pesquisas estão sendo realizadas no campo da adaptação de conteúdo. Um dos desafios nesse campo é definir, a partir de uma requisição do usuário, quais serviços de adaptação serão necessários e em que ordem estes serão executados. Para que essa decisão seja tomada corretamente são necessárias informações sobre o contexto de entrega e os serviços de adaptação disponíveis. Essas informações são descritas por meio de perfis e regras, sendo que no momento a maioria das soluções propostas se baseia em modelos proprietários e incompatíveis entre si. Além disso, a descoberta de serviços geralmente é amplamente baseada em comparações sintáticas, o que compromete a descoberta e composição de serviços. Com o objetivo de contribuir para a área de adaptação de conteúdo, esta dissertação define um conjunto de perfis e regras baseado em ontologias. Além disso, demonstra como as regras devem ser integradas aos perfis de serviços, proporcionando uma solução que seja independente de novos tipos de serviços e regras. Também são apresentados os benefícios que a descoberta e composição de serviços obtêm com o uso de semântica em um ambiente aberto como a Web. A implementação e o estudo de caso dessas propostas foi baseado num framework para adaptação de conteúdo baseado em componentes. Para estender a sua funcionalidade com o propósito de suportar ontologias, e outras funções necessárias, componentes foram reusados, adaptados e criados. Essa extensão viabilizou a realização do estudo de caso e a validar a solução proposta.

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LINS, Fernando Antonio Aires. "Composição adaptativa de Web services." Universidade Federal de Pernambuco, 2007. https://repositorio.ufpe.br/handle/123456789/2708.

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Web services têm desempenhado um importante papel no desenvolvimento de aplicações distribuídas. Em particular, a possibilidade de composição de serviços já implementados com o intuito de prover uma nova funcionalidade se constitui uma abordagem interessante para a construção de sistemas distribuídos e de processos de negócios (business processes), na medida em que diminui o tempo total de desenvolvimento e promove a reusabilidade de serviços já testados e utilizados. A possibilidade de realizar a composição de web services de forma dinâmica, em tempo de execução, aparece nesse contexto com uma elevada importância. A composição dinâmica permite que mudanças sejam percebidas pelo sistema durante a sua execução, sem a necessidade de reinicialização de sistemas, o que poderia levar a indisponibilidade do serviço e a possível perda de clientes. Algumas propostas têm surgido para composição dinâmica de web services, mas elas não adotam especificações já estáveis e notadamente difundidas, como WS-BPEL. Ao mesmo tempo, estas propostas usualmente implicam em modificações nas regras da especificação dos processos de negócios, dificultando ainda mais a implementação do sistema. Este trabalho propõe uma nova abordagem para possibilitar a adaptabilidade na composição de web services através de modificações na semântica da primitiva de invocação de serviços, mantendo a sintaxe do principal padrão existente para este fim (WS-BPEL) inalterada. A partir das modificações propostas, programadores podem definir composições dinâmicas de web services sem alterar o código fonte da aplicação. Como implementar a adaptação passa a ser tarefa do ambiente e não do programador, o que torna esta tarefa mais transparente para o mesmo. Por fim, a adaptabilidade surgiria como mais uma possibilidade no projeto, mantendo todas as outras características da composição inalteradas

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Loukil, Mehdi. "Gestion de contexte pour l'optimisation de l'accès et l'adaptation des services sur des environnements hétérogènes." Phd thesis, Institut National des Télécommunications, 2012. http://tel.archives-ouvertes.fr/tel-00843598.

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Dans le domaine des TIC, les services de demain seront certainement basés sur des systèmes ubiquitaires, omniprésents et pervasifs. Ces systèmes devront prendre en considération différents paramètres provenant de l'environnement de l'utilisateur, c'est à dire son contexte. Le contexte de l'utilisateur peut être composé d'informations statiques ou dynamiques, objectives ou subjectives, quantitatives ou qualitatives. Il peut inclure des données telles que la localisation géographique, les caractéristiques du terminal utilisé, la température ambiante, l'humeur de l'utilisateur. Afin d'améliorer la QoS et la QoE, les services et les systèmes doivent être adaptés aux changements du contexte des utilisateurs. Le contexte doit donc être collecté et interprété et les règles d'adaptation du système doivent être définies. Sur les systèmes étendus, riches, dynamiques et hétérogènes, tels que ceux considéré dans le cadre de cette thèse, ces opérations doivent être automatisées. Vu la quantité et la complexité des données contextuelles à considérer, l'utilisation de la sémantique dans la gestion de contexte peut faciliter cette automatisation et ouvrir la porte au raisonnement et à l'adaptation automatiques. Aujourd'hui, peu de solutions viables existent pour cette problématique. Nous proposons alors d'utiliser et d'adapter des mécanismes et technologies provenant du web sémantique pour décrire et manipuler les informations de contexte. Dans un premier temps, nous avons proposé une méthodologie de conception qui nous permit de proposer " Ubiquity-Ont " : une ontologie générique au domaine des TIC, flexible et extensible. Les données de contexte ont alors été décrites sous forme de concepts et d'instances, reliés par des relations sémantiques. Nous avons ensuite proposé une architecture overlay, composée de deux niveaux de vitalisation et permettant d'intégrer un gestionnaire de contexte, basé sur la sémantique, sur des environnements réseaux et services. Cette solution overlay permet de (a) masquer l'hétérogénéité des composants du système et (b) d'augmenter virtuellement les entités du système existant par les capacités nécessaires à la manipulation et au raisonnement sur les données sémantiques du contexte. Nos propositions ont étés implémentées et testées sur une plateforme réelle et appliquées à deux cas d'études : Gestion de la mobilité sur des environnements de réseaux d'accès hétérogènes et Optimisation de la consommation d'énergie dans les terminaux mobiles

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Ramakrishnan, Lavanya. "Multi-level adaptation for performability in dynamic web service workflows." [Bloomington, Ind.] : Indiana University, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3378395.

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Thesis (Ph.D.)--Indiana University, Dept. of Computer Science, 2009.
Title from PDF t.p. (viewed on Jul 12, 2010). Source: Dissertation Abstracts International, Volume: 70-10, Section: B, page: 6353. Adviser: Dennis Gannon.

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Gschwind, Benoît. "Composition automatique et adaptative de services web pour la météorologie." Phd thesis, École Nationale Supérieure des Mines de Paris, 2009. http://tel.archives-ouvertes.fr/tel-00460604.

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Les données et les observations sont des éléments fondamentaux dans les progrès de la science. Leur accès et leur partage sont cruciaux pour les chercheurs. Ces derniers se sont appuyés sur Internet et les services Web ces dernières années, mais cette solution n'est pas entièrement satisfaisante. Il y a en particulier en météorologie un décalage entre les besoins et les informations disponibles qui peut se résoudre en développant des outils permettant de composer les services Web entre eux. Cette composition permet d'accomplir des tâches qu'un service seul n'aurait pas pu réaliser. Pour répondre aux besoins exprimés, une méthode de composition doit être automatique et adaptative, signifiant qu'une composition ne doit pas nécessiter l'intervention de l'homme et qu'elle doit prendre en compte la disponibilité et le résultat de l'exécution des services Web. Pour combler ce décalage, mes objectifs sont de proposer, formaliser et développer une telle méthode. La première contribution est une formalisation des besoins spécifiques de la météorologie pour la composition de services Web. Cette thèse met en évidence les différences entre les services Web utilisés dans le domaine de la météorologie vis-à-vis des services Web habituellement rencontrés comme ceux de e-Commerce. Ma thèse propose également une nouvelle méthode de composition de services Web permettant la concaténation de données et proposant un moyen d'évaluer la qualité de ces compositions. Enfin, elle propose une méthode pour évaluer les méthodes de composition, qui répond aux besoins en météorologie.

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Cavalcante, Everton Ranielly de Sousa. "Cloud Integrator: uma plataforma para composi??o de servi?os em ambientes de computa??o em nuvem." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18065.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
With the advance of the Cloud Computing paradigm, a single service offered by a cloud platform may not be enough to meet all the application requirements. To fulfill such requirements, it may be necessary, instead of a single service, a composition of services that aggregates services provided by different cloud platforms. In order to generate aggregated value for the user, this composition of services provided by several Cloud Computing platforms requires a solution in terms of platforms integration, which encompasses the manipulation of a wide number of noninteroperable APIs and protocols from different platform vendors. In this scenario, this work presents Cloud Integrator, a middleware platform for composing services provided by different Cloud Computing platforms. Besides providing an environment that facilitates the development and execution of applications that use such services, Cloud Integrator works as a mediator by providing mechanisms for building applications through composition and selection of semantic Web services that take into account metadata about the services, such as QoS (Quality of Service), prices, etc. Moreover, the proposed middleware platform provides an adaptation mechanism that can be triggered in case of failure or quality degradation of one or more services used by the running application in order to ensure its quality and availability. In this work, through a case study that consists of an application that use services provided by different cloud platforms, Cloud Integrator is evaluated in terms of the efficiency of the performed service composition, selection and adaptation processes, as well as the potential of using this middleware in heterogeneous computational clouds scenarios
Com o avan?o do paradigma de Computa??o em Nuvem, um ?nico servi?o oferecido por uma plataforma de nuvem pode n?o ser suficiente para satisfazer todos os requisitos da aplica??o. Para satisfazer tais requisitos, ao inv?s de um ?nico servi?o, pode ser necess?ria uma composi??o que agrega servi?os providos por diferentes plataformas de nuvem. A fim de gerar valor agregado para o usu?rio, essa composi??o de servi?os providos por diferentes plataformas de Computa??o em Nuvem requer uma solu??o em termos de integra??o de plataformas, envolvendo a manipula??o de um vasto n?mero de APIs e protocolos n?o interoper?veis de diferentes provedores. Nesse cen?rio, este trabalho apresenta o Cloud Integrator, uma plataforma de middleware para composi??o de servi?os providos por diferentes plataformas de Computa??o em Nuvem. Al?m de prover um ambiente que facilita o desenvolvimento e a execu??o de aplica??es que utilizam tais servi?os, o Cloud Integrator funciona como um mediador provendo mecanismos para a constru??o de aplica??es atrav?s da composi??o e sele??o de servi?os Web sem?nticos que consideram metadados acerca dos servi?os, como QoS (Quality of Service), pre?os etc. Adicionalmente, a plataforma de middleware proposta prov? um mecanismo de adapta??o que pode ser disparado em caso de falha ou degrada??o da qualidade de um ou mais servi?os utilizados pela aplica??o em quest?o, a fim de garantir sua a qualidade e disponibilidade. Neste trabalho, atrav?s de um estudo de caso que consiste de uma aplica??o que utiliza servi?os providos por diferentes plataformas de nuvem, o Cloud Integrator ? avaliado em termos da efici?ncia dos processos de composi??o de servi?os, sele??o e adapta??o realizados, bem como da potencialidade do seu uso em cen?rios de nuvens computacionais heterog?neas

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Abdeldjelil, Hanane. "Une approche adaptative basée sur la diversité pour la gestion des fautes dans les services Web." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10212/document.

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Les services Web tolérants aux fautes sont des composants avec une grande résilience aux défaillances qui résultent de différentes fautes imprévues, par exemple des bugs logiciels ou crash de machine. Comme il est impossible de prévoir l'apparition d'éventuelles fautes, de nombreuses stratégies consistent à dupliquer, d'une manière passive ou active, les composants critiques (eg. services Web) qui interagissent durant une exécution d'application distribuée (eg. composition). La capacité d'une application à continuer l exécution en présence de défaillances de composants référé a la Tolérance aux Fautes (TF). La duplication est la solution largement utilisée pour rendre les composants tolérants aux fautes. La TF peut être assurée à travers la réplication ou la diversité. Nous nous intéressons particulièrement dans cette thèse à la diversité, et nous montrons comment un ensemble de services Web sémantiquement équivalents qui fournissent la même fonctionnalité (eg. prévisions météo), mais qui l'implémentent différemment, collaborent pour rendre un service Web TF. Nous illustrons les limites de la réplication (présence de fautes répliquées), et proposons la diversité comme une solution alternative. En effet, la littérature a révélé un intérêt limité dans l'utilisation de la diversité pour rendre les services Web tolérants aux fautes
Fault Tolerant Web services are components with higher resilience to failures that result out of various unexpected faults for instance software bugs and machine crashes. Since it is impractical to predict the potential occurrence of a fault, a widely used strategy consists of duplicating, in a passive or active way, critical components (e.g., Web services) that interact during a distributed application execution (e.g., composition). The ability of this application to continue operation despite component failures is referred to as Fault Tolerance (FT). Duplication is usually put forward as a solution to make these components fault tolerant. It is achieved through either replication or diversity. In this thesis, we are particularly interested in diversity, and we show how semantically similar Web services, i.e., offer same functionality (e.g., Weather Forecast) but implement this functionality differently in terms of business logic and technical resources, collaborate together to make web services fault tolerant. We illustrate the limitations of replication (e.g., presence of replicated faults) and suggests diversity as an alternative solution. Our literature review revealed a limited interest in diversity for FT Web services

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Fleischmann, Ana Marilza Pernas. "Sensibilidade à situação em sistemas educacionais na web." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/56845.

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Adaptação e sensibilidade ao contexto andam juntos em diferentes tipos de aplicações. A sensibilidade ao contexto não necessariamente implica em adaptação, mas para que um sistema sensível ao contexto possa guiar uma adaptação efetiva, precisa acompanhar a ocorrência de determinados eventos no sistema e reagir de forma adequada a estes eventos. Este caráter adaptativo tem sido buscado em sistemas Web, de forma a se comportarem de maneira personalizada em atendimento às necessidades particulares do usuário. Dentre uma diversidade de sistemas Web que se propõem a apresentar como diferencial caráter sensível ao contexto do usuário, este trabalho estuda um domínio de aplicação específico: os sistemas de educação adaptativos baseados na Web. Este domínio se mostra crítico, pois necessita ser personalizado tendo em vista um usuário não comum e com uma série de particularidades que devem ser levadas em conta: o aluno. O objetivo principal deste trabalho é apresentar uma solução para o problema da adaptação de ações sensíveis às situações vivenciadas por alunos em um sistema de educação adaptativo baseado na Web. Este problema engloba diversas questões que são atualmente foco de pesquisa em áreas relacionadas à sensibilidade ao contexto, entre elas: (i) as formas de obtenção dos dados relativos ao contexto do aluno; (ii) a análise dos diferentes grupos e modelos de contexto que descrevem a situação em si, vivenciada pelo aluno no momento atual; (iii) as formas de avaliação e relacionamento dos dados de contexto do aluno, de forma a permitir inferência de sua situação atual. Para este fim, foi desenvolvida uma solução capaz de auxiliar o funcionamento de sistemas de educação adaptativos, de forma a apresentarem caráter reativo à situação vivenciada pelo aluno. A solução desenvolvida consiste de um módulo de sensibilidade à situação, construído com o objetivo de analisar as diversas particularidades existentes no cotidiano atual do aluno, se mantendo útil a ele independentemente do seu local atual, do dispositivo computacional utilizado e da tarefa em curso, respeitando as características individuais do aluno. De acordo com a situação detectada, ações de adaptação são fornecidas à mídia adaptativa, com intuito de prover uma experiência educacional voltada às necessidades reais do aluno. Ao final, o funcionamento da solução proposta foi simulado em conjunto a um ambiente de ensino real, de forma a verificar sua aplicabilidade prática.
Adaptation and context awareness walk together in different kinds of applications. Context awareness doesn’t imply necessarily in adaptation, but an adaptive system in order to guide an effective adaptation need to be aware about the occurrence of specific events and properly react to them. This adaptive character has been looked in web systems, in order to behave in a personalized way in attending the particular needs of the user. Among a variety of web systems that propose to present a context aware character, this work presents a case study in a specific application domain: web-based adaptive educational systems. This area is critical because the system needs to be customized in order to attend a not common user, with a variety of particularities that should be taken into account: the student. The main objective of this work is to present a solution to the problem of adaptation of situation-aware actions lived by students in a web-based adaptive educational system. This problem involves several issues that are currently focus of research in areas related with context-awareness, like: (i) the ways of obtaining student’s context data, which often lead to uncertain and ambiguous analysis (ii) the analysis of different groups and context models that describe the situation itself, experienced by the student at the present time, (iii) the ways of evaluating and correlating student’s context data, to allow the inference of their current situation. To this end, we developed a solution capable to assist the functioning of adaptive educational systems; in order to present a reactive character to the situations lived by the student. The solution consists on situation-aware module which aiming at evaluating the several particularities of the student’s actual routine to remain useful to him, regardless of his current location, the computing device used, day of week and the ongoing task, respecting the individual characteristics of the student. According to the detected situation, adaptive actions are presented to the adaptive hypermedia, aiming at providing a better educational experience to the student. At the end of this work, the solution developed is tested with a real e-learning environment to verify its practical appliance.

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Salman, Mohammed Daoud. "Systèmes d'expérimentation à distance via internet : rôle de la simulation et adaptation de la qualité de service." Evry-Val d'Essonne, 2004. http://www.theses.fr/2004EVRY0002.

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Les systèmes d'expérimentation à distance représentent un nouveau concept de systèmes de téléoperation basé sur l'Internet(internet-based teleoperation systems). Il permet à des utilisateurs éloignés de contrôler un système placé à distance. Cette thèse propose des technologies et outils essentiels pour le fonctionnement propre de ces systèmes d'expérimentation à distance. En premier lieu, elle présente une implémentation d'une architecture de processus de simulation basé sur le web qui pourrait être intégrée dans des systèmes d'expérimentation à distances en utilisant les fonctionnalités du world wide web (www), des java-servlet et de matlab. Par la suite, nous proposons une approche de l'évaluation de la perte des paquets courante sur Internet et nous utilisons ce facteur comme un indicateur de l'état de congestion du réseau. A partir de cette indication nous proposons un mécanisme ad hoc pour l'adaptation de la qualité des services (QoS) au niveau des applications. Finalement, en prenant en considération toutes les perspectives proposées, un démonstrateur est présenté. Ce prototype est développé dans notre laboratoire dans la perspective de développer un système de surveillance à distance pour des personnes atteintes, entre autre, par des pathologies cardiaques. Ce travail est une partie de projet MediVille qui a pour vocation de proposer de nouveaux services dans le domaine de la santé en milieu urbain. Ce projet, financé dans le cadre de l'appel d'offre ACI-Ville utilise les nouvelles technologies d'information et de la télécommunication comme un support à l'Hospitalisation à Domicile (HAD)
Remote-Experimentation is a new concept of Internet Based Teleoperation Systems (IBTS). It enables remote users to manipulate a controlled system from a distance locations. This thesis proposes different technologies and tools needed for the proper function of Remote-Experimentation systems. First, it implements an architecture of a Web-based simulation process which could be integrated within Remote-Experimentation systems using the functionalities of World Wide Web (WWW), Java-Servlet, and Matlab. Second, it provides an insight into the loss behaviour (packet losses) indicated in the Internet and uses this factor as a congestion state indicator of the network. Based on this indication, it proposes a proper mechanism for QoS-adaptation at the application level. Finally, taking into account all the proposed perspectives, a prototype of a demonstrator in the domain of remote surveillance of a patient in the cardiac pathologies is shown. It is developed in our Laboratory. This work is a part of ACI-Ville project. This project proposes new urban services in the domain of health. It uses the new technologies of informatics and communication as a support to Home Hospitalisation

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Alférez, Salinas Germán Harvey. "Achieving Autonomic Web Service Compositions with Models at Runtime." Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/34672.

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Over the last years, Web services have become increasingly popular. It is because they allow businesses to share data and business process (BP) logic through a programmatic interface across networks. In order to reach the full potential of Web services, they can be combined to achieve specifi c functionalities. Web services run in complex contexts where arising events may compromise the quality of the system (e.g. a sudden security attack). As a result, it is desirable to count on mechanisms to adapt Web service compositions (or simply called service compositions) according to problematic events in the context. Since critical systems may require prompt responses, manual adaptations are unfeasible in large and intricate service compositions. Thus, it is suitable to have autonomic mechanisms to guide their self-adaptation. One way to achieve this is by implementing variability constructs at the language level. However, this approach may become tedious, difficult to manage, and error-prone as the number of con figurations for the service composition grows. The goal of this thesis is to provide a model-driven framework to guide autonomic adjustments of context-aware service compositions. This framework spans over design time and runtime to face arising known and unknown context events (i.e., foreseen and unforeseen at design time) in the close and open worlds respectively. At design time, we propose a methodology for creating the models that guide autonomic changes. Since Service-Oriented Architecture (SOA) lacks support for systematic reuse of service operations, we represent service operations as Software Product Line (SPL) features in a variability model. As a result, our approach can support the construction of service composition families in mass production-environments. In order to reach optimum adaptations, the variability model and its possible con figurations are verifi ed at design time using Constraint Programming (CP). At runtime, when problematic events arise in the context, the variability model is leveraged for guiding autonomic changes of the service composition. The activation and deactivation of features in the variability model result in changes in a composition model that abstracts the underlying service composition. Changes in the variability model are refl ected into the service composition by adding or removing fragments of Business Process Execution Language (WS-BPEL) code, which are deployed at runtime. Model-driven strategies guide the safe migration of running service composition instances. Under the closed-world assumption, the possible context events are fully known at design time. These events will eventually trigger the dynamic adaptation of the service composition. Nevertheless, it is diffi cult to foresee all the possible situations arising in uncertain contexts where service compositions run. Therefore, we extend our framework to cover the dynamic evolution of service compositions to deal with unexpected events in the open world. If model adaptations cannot solve uncertainty, the supporting models self-evolve according to abstract tactics that preserve expected requirements.
Alférez Salinas, GH. (2013). Achieving Autonomic Web Service Compositions with Models at Runtime [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34672
TESIS

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Semprebom, Tiago. "Diferenciação de serviços em servidores web baseada em escalonamento adaptativo e controle de admissão." Florianópolis, SC, 2007. http://repositorio.ufsc.br/xmlui/handle/123456789/90498.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica
Made available in DSpace on 2012-10-23T11:32:50Z (GMT). No. of bitstreams: 1 239807.pdf: 18187149 bytes, checksum: 88af1f523d5e0f43d2768d9bd593768c (MD5)
Com o paradigma de melhor esforço (best-effort) oferecido pela Internet atual, clientes de novos tipos de aplicações (VoIP e IPTV) têm que conviver com aplicações tradicionais da Internet como: e-mail e simples web sites. Contudo, verifica-se que nem todos os tipos de tráfego têm os mesmos requisitos de confiabilidade, segurança e urgência. Considerando-se a infra-estrutura de rede, existem algumas propostas nesse sentido, elaboradas sob a coordenação da IETF (Internet Engineering Task Force). Entretanto, em nível de aplicação os esforços ainda são limitados, não sendo encontrados na grande maioria dos servidores web.

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Charton, Romaric. "Des agents intelligents dans un environnement de communication multimédia : vers la conception de services adaptatifs." Nancy 1, 2003. http://www.theses.fr/2003NAN10174.

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Cette thèse présente nos travaux sur les stratégies d'interaction dans les systèmes multi-agents hétérogènes (hSMA), où l'humain est placé dans le système, et leur application pour fournir des services de communication multimédia. Pour pallier l'hétérogénéité des agents, notre solution consiste à introduire un médiateur et à définir une modélisation où les agents endossent des rôles permettant de construire des classes de service. Un service résulte alors d'une collaboration donnant satisfaction à un sous-ensemble d'agents. Pour définir le comportement des agents, nous avons envisagé divers types de planification, puis l'apprentissage par renforcement dans les Processus de Décision Markoviens (MDP). Nous avons également étudié la modélisation des utilisateurs et le suivi de l'interaction pour l'adaptation aux autres agents et aux aléas d'exécution. La thèse décrit la spécification d'un médiateur capable d'aider un utilisateur dans sa recherche d'informations. Elle présente également une architecture à quatre niveaux d'abstraction et une bibliothèque logicielle utilisés pour concevoir et exécuter des services adaptatifs
This thesis describes our works on interaction policies for heterogeneous multiagent systems (hMAS), where human beings are placed in the system, and their application for providing multimedia communication services adaptation. To deal with agent heterogeneity, our solution proposes to insert a mediator in the system. We have defined a model where agents assume generic roles that can be assembled to build service classes. A service arises from a collaboration that satisfies a subset of agents. In order to define the behavior of the agents, we have considered different kinds of planning and chosen to use reinforcement learning in Markov Decision Processes (MDP). We have also studied user modeling and interaction monitoring for the adaptation to other agents and to execution hazards. The thesis details the specification of a mediator that is able to help a user in an information retrieval service. It also presents our architecture with four abstraction levels and a software library that we have implemented to build and execute adaptive services

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Leite, Marco Antonio Aparecido. "Proposta de uma arquitetura (framework) tecnológica que apóia o desenvolvimento do aprendizado individual e adaptativa em instituições de ensino." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18140/tde-31072017-114317/.

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A maioria das instituições educacionais prioriza o desenvolvimento de sistemas informacionais com foco operacional ou administrativo em seu primeiro momento postergando o desenvolvimento de sistemas que controlam o treinamento e aprendizado. A arquitetura proposta visa adaptar-se aos sistemas existentes, suportando a utilização de tecnologias que ajudam a evolução do treinamento e aprendizado de forma individual e não apenas utilizar tecnologia como um veículo distribuidor de informação, característica presente na maioria das apresentações multimídia. Apresenta uma revisão bibliográfica sobre a importância do aprendizado individual, identificando como as avaliações empregadas de forma presencial podem ter um formato mais dinâmico no ambiente virtual. Também são avaliadas tecnologias que fornecem subsídios para a criação da arquitetura, suprimindo algumas deficiências de fragmentação e de isolamento do aprendizado do aluno, melhorando o desempenho do conhecimento individual. É apresentado no final um modelo de estrutura que irá permitir a integração das tecnologias abordadas que apóia o desenvolvimento do aprendizado individual e adaptativa a sistemas de informações existentes em instituições de ensino.
The majority of educational institutions prioritize the development of informational systems with an operational or administrative focus at first, depreciating the development of systems that control training and learning. The proposed architecture aims to adapt itself to existing systems, supporting the application of technologies that help the evolution of training and learning in an individual way and not only using technology as a vehicle that distributes information, characteristic which is present in most of the multimedia presentations. The paper presents a review of the literature on the importance of individual learning, identifying how the evaluations employed in a present way may have a more dynamic format in the virtual environment. Technologies which supply subsides for the creation of the architecture are also evaluated, suppressing some deficiencies of fragmentation and isolation of the student\'s learning, improving the performance of the individual learning. It is presented at the end a model of structure that will allow the integration of the approached technologies which support the development of the individual learning and which can be adapted to existing information systems effective in teaching institutions.

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Papageorgiou, Apostolos [Verfasser], Ralf [Akademischer Betreuer] Steinmetz, and Claudia [Akademischer Betreuer] Linnhoff-Popien. "Service-Oriented Computing with Wireless Participants - Adaptation Mechanisms and Decision Support for Lightweight Web Service Consumption / Apostolos Papageorgiou. Betreuer: Ralf Steinmetz ; Claudia Linnhoff-Popien." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2012. http://d-nb.info/1106116054/34.

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Ye, Zakaria. "Analyse de Performance des Services de Vidéo Streaming Adaptatif dans les Réseaux Mobiles." Thesis, Avignon, 2017. http://www.theses.fr/2017AVIG0219/document.

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Le trafic vidéo a subi une augmentation fulgurante sur Internet ces dernières années. Pour pallier à cette importante demande de contenu vidéo, la technologie du streaming adaptatif sur HTTP est utilisée. Elle est devenue par ailleurs très populaire car elle a été adoptée par les différents acteurs du domaine de la vidéo streaming. C’est une technologie moins couteuse qui permet aux fournisseurs de contenu, la réutilisation des serveurs web et des caches déjà déployés. En plus, elle est exempt de tout blocage car elle traverse facilement les pare-feux et les translations d’adresses sur Internet. Dans cette thèse, nous proposons une nouvelle méthode de vidéo streaming adaptatif appelé “Backward-Shifted Coding (BSC)”. Il se veut être une solution complémentaire au standard DASH, le streaming adaptatif et dynamique utilisant le protocole HTTP. Nous allons d’abord décrire ce qu’est la technologie BSC qui se base sur le codec (encodeur décodeur) à multi couches SVC, un algorithme de compression extensible ou évolutif. Nous détaillons aussi l’implémentation de BSC dans un environnement DASH. Ensuite,nous réalisons une évaluation analytique de BSC en utilisant des résultats standards de la théorie des files d’attente. Les résultats de cette analyse mathématique montrent que le protocole BSC permet de réduire considérablement le risque d’interruption de la vidéo pendant la lecture, ce dernier étant très pénalisant pour les utilisateurs. Ces résultats vont nous permettre de concevoir des algorithmes d’adaptation de qualité à la bande passante en vue d’améliorer l’expérience utilisateur. Ces algorithmes permettent d’améliorer la qualité de la vidéo même étant dans un environnement où le débit utilisateur est très instable.La dernière étape de la thèse consiste à la conception de stratégies de caching pour optimiser la transmission de contenu vidéo utilisant le codec SVC. En effet, dans le réseau, des serveurs de cache sont déployés dans le but de rapprocher le contenu vidéo auprès des utilisateurs pour réduire les délais de transmission et améliorer la qualité de la vidéo. Nous utilisons la programmation linéaire pour obtenir la solution optimale de caching afin de le comparer avec nos algorithmes proposés. Nous montrons que ces algorithmes augmentent la performance du système tout en permettant de décharger les liens de transmission du réseau cœur
Due to the growth of video traffic over the Internet in recent years, HTTP AdaptiveStreaming (HAS) solution becomes the most popular streaming technology because ithas been succesfully adopted by the different actors in Internet video ecosystem. Itallows the service providers to use traditional stateless web servers and mobile edgecaches for streaming videos. Further, it allows users to access media content frombehind Firewalls and NATs.In this thesis we focus on the design of a novel video streaming delivery solutioncalled Backward-Shifted Coding (BSC), a complementary solution to Dynamic AdaptiveStreaming over HTTP (DASH), the standard version of HAS. We first describe theBackward-Shifted Coding scheme architecture based on the multi-layer Scalable VideoCoding (SVC). We also discuss the implementation of BSC protocol in DASH environment.Then, we perform the analytical evaluation of the Backward-Sihifted Codingusing results from queueing theory. The analytical results show that BSC considerablydecreases the video playback interruption which is the worst event that users can experienceduring the video session. Therefore, we design bitrate adaptation algorithms inorder to enhance the Quality of Experience (QoE) of the users in DASH/BSC system.The results of the proposed adaptation algorithms show that the flexibility of BSC allowsus to improve both the video quality and the variations of the quality during thestreaming session.Finally, we propose new caching policies to be used with video contents encodedusing SVC. Indeed, in DASH/BSC system, cache servers are deployed to make contentsclosed to the users in order to reduce network latency and improve user-perceived experience.We use Linear Programming to obtain optimal static cache composition tocompare with the results of our proposed algorithms. We show that these algorithmsincrease the system overall hit ratio and offload the backhaul links by decreasing thefetched content from the origin web servers

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Qiao, Ming. "Automatic quality of service adaptation for composite web services." Thesis, 2009. http://spectrum.library.concordia.ca/976224/1/MR63228.pdf.

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Quality of Services (QoS) management has become an important issue for Web services. Indeed, QoS is becoming a crucial and a distinguishing criterion among functionally equivalent Web services. QoS Management consists of two complementary tasks: monitoring and adaptation. Both are very challenging because of the unpredictable and dynamic nature of Web service composition. We are motivated to solve the QoS problem by taking advantage of some characteristics of composite Web services, such as their similarity to traditional workflows. In this thesis, we propose a broker based architecture that enables dynamic QoS monitoring and adaptation for composite Web services. Our approach consists of dynamically changing the execution paths of composed Web services by instrumenting the BPEL process. A new construct flexPath is introduced for supporting alternate execution paths definition in BPEL. We developed a BPEL compiler allowing automatic instrumentation for BPEL definition files. The BPEL process is deployed using the instrumented definition files in order to interact with the QoS broker during execution. The QoS broker is a key component in our architecture and is responsible of monitoring the QoS and managing the adaptation. We propose a broker that enables runtime monitoring of QoS, prediction of potential QoS violation, and the selection of the best execution path of the process in order to improve QoS when needed. We developed a prototype to evaluate our proposed architecture. A case study is also presented through an example BPEL process and a number of partner Web services. The performance of the QoS adaptation has been analyzed and the results showed that the QoS of the BPEL process has been considerably adapted and improved comparing to the original one. In addition, we analyzed the major factors that affect the performance of our prototype tool.

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Syu, Jyun-Yang. "An Ontology-Based Approach to Automatic Adaptation of Web Services." 2004. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-3007200403240600.

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Syu, Jyun-Yang, and 許均揚. "An Ontology-Based Approach to Automatic Adaptation of Web Services." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/15399760853131573924.

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碩士
國立臺灣大學
資訊管理研究所
92
With XML-based standards for interface description and message exchange, Web services have become a widely accepted solution to the interoperatability problem between heterogenous and incompatible systems over the Internet. As Web Services become more and more popular, there may be more than one service providers that provide a similar service, and the user may want to find the best fit for him. Many researches use criteria such as QoS or desired contents to determine the Web Services that the requester actually needs. Most of these researches assume that all operations doing the same thing will use the same operation name and the same input and output parameters in the same order. This is not true in practice. The goal of Web service adaptation is to adapt the inputs and outputs of one operation to the inputs and outputs of another automatically at runtime. In this thesis, we provide an approach to Web service adaptation with the help of ontology definition languages such as OWL and OWL-S. We assume there exists a shared ontology between Web services in the same industry, and the input and output parameters have their types come from this shared ontology. With OWL-S and some extension added to annotate the Web services, we can adapt one operation to another automati- cally. Our research group have implemented a prototype system to help customer make a trip plan, where our Web service adaptation acts as one part of this system.

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LEMLOUMA, Tayeb. "Architecture de Négociation et d'Adaptation de Services Multimédia dans des Environnements Hétérogènes." Phd thesis, 2004. http://tel.archives-ouvertes.fr/tel-00006253.

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Les progrès technologiques récents ont permis l'apparition d'une grande variété de nouveaux moyens pour accéder et utiliser l'information multimédia du Web en tout lieu et à tout moment. L'hétérogénéité des appareils d'accès s'est accompagné une évolution importante de l'information disponible sur le réseau. Aujourd'hui, on trouve une multitude de formats complexes avec de nouvelles fonctionnalités, telles que la vidéo interactive, les animations 3D et le dessin vectoriel. Ces formats s'appuient sur de nouveaux modèles de documents qui intègrent une structure logique, spatiale, temporelle et une dimension hypermédia.

Face à cette évolution, il est nécessaire de concevoir des systèmes qui permettent l'accès et l'utilisation de l'information sous une forme qui corresponde aux contraintes imposées par l'environnement. Cette thèse a pour objectif de contribuer à l'adaptation et à la négociation des contenus en considérant les limitations des utilisateurs et les contraintes de leur environnement. Nous présentons une architecture flexible appelée NAC qui permet de définir les composants qui interviennent dans la négociation et l'adaptation de contenu, et qui décrit comment ces composants sont organisés.

NAC permet plusieurs types d'adaptation : une adaptation structurelle, une adaptation sémantique et une adaptation des ressources médias. Ces types d'adaptation sont basés sur les différents contextes des clients (caractéristiques des terminaux, préférences des utilisateurs, etc.). Nous proposons également un modèle de description de contextes UPS (schémas universels pour la description des profils), un protocole de négociation et un ensemble de techniques d'adaptation. Les concepts de l'architecture NAC ont contribué aux travaux de standardisation du consortium W3C, en particulier au cadre de travail CC/PP et aux travaux sur l'indépendance des terminaux. Cette étude est complétée par une évaluation de performances qui démontre que le système proposé est exploitable dans la pratique.

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Papageorgiou, Apostolos. "Service-Oriented Computing with Wireless Participants - Adaptation Mechanisms and Decision Support for Lightweight Web Service Consumption." Phd thesis, 2012. https://tuprints.ulb.tu-darmstadt.de/3012/1/Apo_Dissertation.pdf.

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At the crossroads of two hot trends of modern computer science, namely service-orientation and mobile computing, great potentials arise together with tough challenges. The list of advantages of combining these technologies is long and compelling: Outsourcing of data- and processing-intensive software tasks from mobile devices to more capable systems, quick mobile application development through the use of existing software services that are otherwise difficult to implement on mobile devices from scratch, and the list goes on. However, service-oriented messaging and description technologies are characterized by a verbose, self-descriptive nature, in order to achieve interoperability and platform-independence. This renders them often heavyweight and thus not always a good match for the resource-constrained nature of mobile, wireless devices. In the face of the fact that very different devices will coexist in future service-oriented systems, researchers are diligently trying to tackle the aforementioned challenges by developing adaptation mechanisms. These are meant to allow the systems to dynamically and seamlessly switch to configurations that suit each particular participant. When it comes to one of the most important service-oriented technologies, namely Web services, adaptation for resource-constrained devices usually translates to an attempt to use lightweight ways of communication that are dictated by the system context. The striving for enhancements in the field of Web service adaptation mechanisms for wireless participants starts with three simple questions: Which specific adaptation mechanisms can be used and what are their characteristics? Can the development of new adaptation mechanisms contribute to the currently existing possibilities? Which adaptation mechanisms should be used under which wireless system contexts? The systematic and scientific examination of these questions leads to the three corresponding main contributions of this thesis. First, the conducted survey and comparison of Web service adaptation mechanisms is the first work examining the conditions of the wireless system context under which the adaptation mechanisms achieve significant benefits. Thus, the survey results can be used as a basis for examining the two further issues. Second, a new, caching-based Web service adaptation mechanism is presented. The developed mechanism is the first to enable the use of cached responses of external, i.e., third-party, Web services with guaranteed 100% freshness in an automated and generic manner. The freshness of cached objects refers to their probability of being up-to-date. The evaluation proves that the approach can lead to performance enhancements of mobile Web service invocations compared to other approaches that achieve absolute freshness. Third, provided that no single adaptation mechanism is the best-performing under all possible system contexts, the thesis offers insights with regard to the issue of corresponding decision support. Decision support algorithms that are based on the obtained survey results are developed and evaluated with focus on an important, yet uninvestigated aspect, namely the existence of missing system context data. The respective work reveals which data imputation approaches are best suited to the examined scenario. By discussing the above issues within a well-defined future scenario of mediated Web service usage, the thesis provides further contributions, such as architectural solutions, engineering approaches, and problem formulations. All in all, its findings should be interesting for any work in the research area of mobile services.

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Freitas, Marco António Guerreiro de. "Microservices applied to Web and mobile applications internship." Master's thesis, 2018. http://hdl.handle.net/10400.1/12368.

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Microservices is a software architecture that has seen an increase in popularity and use in recent years. Due to its simplicity and ease of implementation it is nowadays the standard reference for web services. This report focuses on the general concepts of microservices and their real-world application. The report was divided into three main points: (a) general concepts of microservices, (b) facial and emotion recognition applied to an adaptive user interface using microservices and (c) restructure an existing web application following a microservices architecture. The first point, (a) general concepts of microservices, introduces the definition of a microservice and what are the main traits that a microservice should have. The second point, (b) describes the implementation of a mobile application with an adaptive user interface that uses microservices for facial and emotional recognition. In this point it is possible to understand how to consume microservices developed by third parties. The third point, (c) describes the restructuring of an existing web application, through a microservices architecture, exemplifying the concepts mentioned in point (a) and small excerpts of code from an open-source project to demonstrate its real-world code usage.
Micro serviços é uma arquitetura de software que cresceu em popularidade e utilização nos anos mais recentes. Devido à sua simplicidade e facilidade de implementação é hoje em dia o padrão referência para serviços web. Este relatório foca os conceitos gerais de micro serviços e a sua aplicação num âmbito profissional. O relatório foi dividido em 3 pontos principais: (a) conceitos gerais de micro serviços, (b) reconhecimento facial e de emoções aplicado a uma interface adaptativa de utilizador utilizando micro serviços e (c) reestruturar uma aplicação web existente seguindo uma arquitetura de micro serviços. O primeiro ponto, o (a) conceitos gerais de micro serviços, introduz a definição de um micro serviço e quais as principais características que um micro serviço deve obedecer. No segundo ponto, (b) descreve-se a implementação de uma aplicação mobile com uma interface adaptativa de utilizador recorrendo a micro serviços para reconhecimento facial e de emoções. Neste ponto é possível compreender como consumir micro serviços desenvolvidos por terceiros. No terceiro ponto, (c) descreve-se a reestruturação de uma aplicação web existente, através de uma arquitetura de micro serviços, exemplificando os conceitos mencionados no ponto (a) e pequenos excertos de código de um projecto open-source para demonstrar a sua utilização.

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Dissertations / Theses on the topic 'Web services adaptation'

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