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

運用語義網本體論來描述網路服務，實現網路服務的自動發現、調用和組合已經被證實是有效的。人工智慧規劃技術就是運用此技術描述網路服務來達到自動化網路服務組合。OWL-S支援使用OWL來描述網路服務的前提與效果，而在OWL的規則描述語言方面，則可以使用SWRL。本論文是以OntoComposer規劃工具為基礎，發展一套前置處理器來簡化其使用，讓使用者不需具備人工智慧規劃描述語言及語義網路服務描述等知識，只要尋找到符合需求之網路服務後，就可以自動轉換成支持條件分支圖規劃器之輸入文件，並在設定目標後進行規劃組合，最後讓組合之複合網路能夠在執行引擎上正確執行。 / Using Semantic Web ontologies to describe Web Services has proven to be effective for automatic service discovery, invokcation and composition. AI planning techniques have been employed to automate the composition of Web Services in this way. OWL-S supports the description of the preconditions and effects of a web service using OWL statements, and SWRL is the language for expressing OWL Rules. OntoComposer is an AI planning based tool for Combining-GraphPlan, an extension for GraphPlan so that supports condition branching. This thesis presents a preprocessor for OntoComposer to simplify its input task so that the user does not have to learn the AI Planning description language and knowledge of the semantic web service description. Just look to meet the demand of web services, our preprocessor will translate them to support branch planning for the input file. After setting the targets the OntoComposer will compose some component web services to a complex web service. Finally, let the composition of web services on the execution engine the correct execution.

De nos jours, nous assistons à l’émigration du Web de données vers le Web orienté services. L’amélioration des capacités et fonctionnalités des moteurs actuels de recherche sur le Web, par des techniques efficaces de recherche et de sélection de services, devient de plus en plus importante. Dans cette thèse, dans un premier temps, nous proposons un cadre de composition de services Web en tenant compte des préférences utilisateurs. Le modèle fondé sur la théorie des ensembles flous est utilisé pour représenter les préférences. L’approche proposée est basée sur une version étendue du principe d’optimalité de Pareto. Ainsi, la notion des top-k compositions est introduite pour répondre à des requêtes utilisateurs de nature complexe. Afin d’améliorer la qualité de l’ensemble des compositions retournées, un second filtre est appliqué à cet ensemble en utilisant le critère de diversité. Dans un second temps, nous avons considéré le problème de la sélection des services Web en présence de préférences émanant de plusieurs utilisateurs. Une nouvelle variante, appelée Skyline de services à majorité, du Skyline de services traditionnel est défini. Ce qui permet aux utilisateurs de prendre une décision « démocratique » conduisant aux services les plus appropriés. Un autre type de Skyline de services est également discuté dans cette thèse. Il s’agit d’un Skyline de Services de nature graduelle et se fonde sur une relation de dominance floue. Comme résultat, les services Web présentant un meilleur compromis entre les paramètres QoS sont retenus, alors que les services Web ayant un mauvais compromis entre les QoS sont exclus. Finalement, nous avons aussi absorbé le cas où les QoS décrivant les services Web sont entachés d’incertitude. La théorie des possibilités est utilisée comme modèle de l’incertain. Ainsi, un Skyline de Services possibilité est proposé pour permettre à l’utilisateur de sélectionner les services Web désirés en présence de QoS incertains. De riches expérimentations ont été conduites afin d’évaluer et de valider toutes les approches proposées dans cette thèse / As we move from a Web of data to a Web of services, enhancing the capabilities of the current Web search engines with effective and efficient techniques for Web services retrieval and selection becomes an important issue. In this dissertation, we present a framework that identifies the top-k Web service compositions according to the user fuzzy preferences based on a fuzzification of the Pareto dominance relationship. We also provide a method to improve the diversity of the top-k compositions. An efficient algorithm is proposed for each method. We evaluate our approach through a set of thorough experiments. After that, we consider the problem of Web service selection under multiple users preferences. We introduce a novel concept called majority service skyline for this problem based on the majority rule. This allows users to make a “democratic” decision on which Web services are the most appropriate. We develop a suitable algorithm for computing the majority service skyline. We conduct a set of thorough experiments to evaluate the effectiveness of the majority service skyline and the efficiency of our algorithm. We then propose the notion of α-dominant service skyline based on a fuzzification of Pareto dominance relationship, which allows the inclusion of Web services with a good compromise between QoS parameters, and the exclusion ofWeb services with a bad compromise between QoS parameters. We develop an efficient algorithm based on R-Tree index structure for computing efficiently the α-dominant service skyline. We evaluate the effectiveness of the α-dominant service skyline and the efficiency of the algorithm through a set of experiments. Finally, we consider the uncertainty of the QoS delivered by Web services. We model each uncertain QoS attribute using a possibility distribution, and we introduce the notion of pos-dominant service skyline and the notion of nec-dominant service skyline that facilitates users to select their desired Web services with the presence of uncertainty in their QoS. We then developappropriate algorithms to efficiently compute both the pos-dominant service skyline and nec-dominant service skyline. We conduct extensive sets of experiments to evaluate the proposed service skyline extensions and algorithms

Composição de serviços é um tópico que tem atraído cada vez mais o interesse por parte de pesquisadores na área de sistemas distribuídos. Além disso, o interesse por ambientes baseados em nuvem tem crescido significativamente conforme o seu uso aumenta e se firma como um importante modelo de negócios. Coreografias são formas de composições de serviços em que não há pontos centrais de falha; a responsabilidade da sua execução é distribuída entre os vários serviços componentes. Devido à natureza distribuída do fluxo de informações e dados de controle, o cumprimento de \\textit{Service Level Agreements} (SLAs) depende estritamente do monitoramento da Qualidade de Serviços (QoS), recursos virtuais da nuvem e mecanismos de reconfiguração dinâmica, capazes de automaticamente adaptar composições a mudanças de estado no sistema. Nesta dissertação, abordamos o estudo do gerenciamento de QoS em coreografias de serviços. Para isso desenvolvemos um sistema de middleware capaz de implantar e gerenciar o QoS de composições. Este teve seu desempenho avaliado utilizando o serviço Amazon EC2. Os resultados da avaliação mostram que com pouco esforço por parte dos desenvolvedores de composições, é possível cumprir o SLA de composições dentro do esperado utilizando escalabilidade horizontal ou vertical provida pelo middleware automaticamente. Adicionalmente, a nossa proposta traz economias em relação ao custo de implantação pois diminui a quantidade de recursos subutilizados. / Service composition has been a hot topic that has attracted the interesting of researchers in the distributed system area. Moreover, the interesting in cloud computing based environment has grown significantly. Its use has grown and it became to be a important business model. Choreographies are an specific kind of service composition that has no single point of failure; the responsibility of execution is distributed among the services. Due to the distributed nature of the these systems, the fulfilment of Service Level Agreements (SLAs) depends strictly on and automatic way to monitoring Quality of Service (QoS) and virtual computional resources as well as dinamic reconfiguration mechanisms, to be capable of automatically adapting compositions to changing environment. In this work, we studied QoS management in service choreographies. In order, we devised a middleware system capable of deploy service compositions and manage QoS of them. The middleware was evaluated using the Amazon EC2 cloud provider. The results shows that with less effort from the composition providers, it is possible to fulfil SLAs using horizontal or vertical scalability provided by the middleware automatically. Additionaly, our proposal brings up a cost reduction of deploy by decreasing the amount of underused resources.

L'informatique pervasive (ou ubiquitaire) est un support pour des environnements contenant denombreux objets (ou dispositifs) disséminés, équipés d'électronique et interconnectés. Ces dispositifsfournissent un accès distant à une multitude de fonctionnalités qui nous aident dans notre vie quotidienne.Les Architectures Orientées Services sont adaptées à la conception de logiciels pervasifs. En effet,chaque dispositif fournit son propre ensemble de fonctionnalités sous la forme de services. Ainsi, enl'absence de mécanisme complémentaire, les utilisateurs se trouvent limités à utiliser les servicesisolément alors que leurs besoins correspondent à des scénarios qui impliquent une composition demultiples services offerts par plusieurs appareils.Dans cette thèse, nous défendons qu'un système pervasif doit : d'une part, permettre aux utilisateursd'exprimer facilement leurs besoins en créant des scénarios et d'autre part, proposer à ses utilisateursune représentation et des moyens de gestion de leur contexte afin qu'ils puissent tirer le meilleur parti deleur environnement et de ses changements. De plus, la présence de plusieurs utilisateurs implique lanécessité de collaborer. Par ailleurs, l'exécution de scénarios doit être résiliente aux changementsenvironnementaux et aux actions des utilisateurs. Elle doit ainsi s'adapter dynamiquement et, si possible,tirer profit du contexte et des changements de l'environnement.Notre contribution, nommée SaS (Scenarios as Services), répond à ces objectifs. Elle propose uneapproche interopérable capable de s'adapter à l'environnement. Elle fournit une représentation persistanteet personnalisable du contexte et inclut un langage de description de scénarios destiné aux utilisateurs.Ces scénarios sont facilement contrôlables, personnalisables et réutilisables. Elle planifie l'exécution pasà pas des scénarios, afin de s'adapter aux changements de l'environnement et de bénéficier desavantages de la mobilité des utilisateurs (exécution d'un scénario, dans la durée, sur plusieurs lieux).Enfin, elle inclut le partage de scénarios qui permet aux utilisateurs de collaborer. Un prototype de SaS,basé sur des normes industrielles (telle qu'OSGi), prouve la faisabilité de notre contribution et nouspermet de l'évaluer sur un cas d'étude simple. / Pervasive (or ubiquitous) computing is a paradigm for environments containing distributedinterconnected devices that embed electronics. These devices provide a remote access to numerousfunctionalities that assist us in our daily life. Service-Oriented Architectures are suitable to design softwarefor pervasive environments. Indeed, each device provides its own set of functionalities as services.Without any extra mechanism, users can only use a single service at a time. Nevertheless, their needsusually correspond to scenarios which involve a composition of multiple services, provided by multipledevices.In this thesis, we advocate that a pervasive system must, on the one hand, enable users to easily expresstheir needs through scenario creation and, on the other hand, propose to users a representation of theircontext so that they can benefit from both their environment and its changes. In addition, the presence ofseveral users implies that users must be able to collaborate.Our contribution, named SaS (Scenarios as Services), fulfils these requirements. It proposes aninteroperable approach that adapts to its environment. It provides users with a customizable andpersistent representation of their context and includes a scenario description language targeted to users.Scenarios are easy to control, customize and reuse. SaS schedules the step-by-step execution ofscenarios to adapt to environmental changes and benefit from user mobility (scenario execution split over time on successive distinct sites). Finally, SaS includes scenario sharing mechanisms which are abasis for collaboration. A prototype of SaS, based on industrial standards (e.g., OSGi), proves thefeasibility of our contribution and serves for its evaluation on a simple use case.

Distributed Smart Camera (DSC) networks are power constrained real-time distributed embedded systems that perform computer vision using multiple cameras. Providing data aggregation techniques that is criti-cal for running complex image processing algorithms on DSCs is a challenging task due to complexity of video and image data. Providing highly desirable SQL APIs for sophisticated query processing in DSC networks is also challenging for similar reasons. Research on DSCs to date have not addressed the above two problems. In this thesis, we develop a novel SOA based middleware framework on a DSC network that uses Distributed OSGi to expose DSC network services as web services. We also develop a novel web service composition scheme that aid in data aggregation and a SQL query interface for DSC net-works that allow sophisticated query processing. We validate our service orchestration concept for data aggregation by providing query primitive for face detection in smart camera network.

In the context of building software systems, Service-oriented Systems (SOS) have become one of the major research topics in the past few years. In SOS, services are basic functional units that can be created, invoked, composed, and if needed deleted on-the-fly. Since these software systems are composed of different services there is no easy way to assure the Quality of Service (QoS), therefore, formal specification of both functional and extra-functional system behaviour, compatibility, and interoperability between different services have become important issues. As a way to address this issues, resource-aware timing behavioural language REMES was chosen to be extended towards service-oriented paradigm with service specific information, such as type, capacity, time-to-serve, etc., as well as Boolean predicate constraints on control flow guarantees. In this thesis we present a design framework that provides a graphical user interface for behaviour modelling of services based on REMES language. NetBeans Visual Library API is used to display editable service diagrams with support for graph-oriented models. A textual dynamic service composition language was implemented, together with means to automatically verify service composition correctness. We ensure also an automated traceability between service specification interfaces, where both modelling levels are combined in an efficient tool for designing SOS.

The Web turns out to be a collection of services that interoperate through the Internet. As the number of services increase, it is getting more and more diffucult for users to find, filter and integrate these services depending on their requirements. Automatic techniques are being developed to fulfill these tasks. The first step toward automatic composition is the discovery of services needed. UDDI which is one of the accepted web standards, provides a registry of web services. However representation capabilities of UDDI are insufficient to search for services on the basis of what they provide. Semantic web initiatives like OWL and OWL-S are promising for locating exact services based on their capabilities. In this thesis, a new semantic service discovery mechanism is implemented based on OWL-S service profiles. The service profiles of an advertisement and a request are matched based on OWL ontologies describing them. In contrast to previous work on the subject, the ontologies of the advertisement and the request are not assumed to be same. In case they are different, schema matching algorithms are applied. Schema matching algorithms find the mappings between the given schema models. A hybrid combination of semantic, syntactic and structural schema matching algorithms are applied to match ontologies

Web service composition is an inevitable aspect of web services technology, which solves complex problems by combining available basic services and ordering them to best suit the problem requirements. Automatic composition gives us flexibility of selecting best candidate services at composition time, this would require the user to define the resource allocation constraints for selecting and composing candidate web services. Resource allocation constraints define restrictions on how to allocate resources, and scheduling under resource allocation constraints to provide proper resource allocation to tasks. In this work, web service composition system named as CWSF (Composite Web Service Framework) constructed for users to define a workflow system in which a rich set of constraints can be defined on web services. On the contrary many technologies and studies, CWSF provides a user-friendly environment for modeling web service composition system. The output of the framework is the scheduling of web service composition in which how and when web services are executed are defined. With this work, a language, CWSL is defined to describe workflow, resource allocation constraints, selection and discovery rules of web services and associated semantic information. An important property of CWSF system is converting web service composition problem into a constraint satisfaction problem to find the best solution that meet the all criteria defined by user. Furthermore, CWSF has ability to display other possible solutions to provides users flexibility. This study also includes semantic matching and mapping facilities for service discovery.

In Web service composition, service discovery and combining suitable services through determination of interoperability among different services are important operations. Utilizing semantics improves the quality and facilitates automation of these operations. There are several previous approaches for semantic service discovery and service matching. In this work, we exploit and extend these semantic approaches in order to make Web service composition process more facilitated, less error prone and more automated. This work includes a service discovery and service interoperability checking technique which extends the previous semantic matching approaches. In addition to this, as a guidance system for the user, a new semantic domain model is proposed that captures semantic relations between concepts in various ontologies.