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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

An integrated methodology for creating composed Web/grid services

Tan, Koon Leai Larry January 2009 (has links)
This thesis presents an approach to design, specify, validate, verify, implement, and evaluate composed web/grid services. Web and grid services can be composed to create new services with complex behaviours. The BPEL (Business Process Execution Language) standard was created to enable the orchestration of web services, but there have also been investigation of its use for grid services. BPEL specifies the implementation of service composition but has no formal semantics; implementations are in practice checked by testing. Formal methods are used in general to define an abstract model of system behaviour that allows simulation and reasoning about properties. The approach can detect and reduce potentially costly errors at design time. CRESS (Communication Representation Employing Systematic Specification) is a domainindependent, graphical, abstract notation, and integrated toolset for developing composite web service. The original version of CRESS had automated support for formal specification in LOTOS (Language Of Temporal Ordering Specification), executing formal validation with MUSTARD (Multiple-Use Scenario Testing and Refusal Description), and implementing in BPEL4WS as the early version of BPEL standard. This thesis work has extended CRESS and its integrated tools to design, specify, validate, verify, implement, and evaluate composed web/grid services. The work has extended the CRESS notation to support a wider range of service compositions, and has applied it to grid services as a new domain. The thesis presents two new tools, CLOVE (CRESS Language-Oriented Verification Environment) and MINT (MUSTARD Interpreter), to respectively support formal verification and implementation testing. New work has also extended CRESS to automate implementation of composed services using the more recent BPEL standard WS-BPEL 2.0.
72

Service composition in converged service environment

HUANG, Cuiting 02 May 2012 (has links) (PDF)
The goal of this thesis is to provide enhanced mechanisms to deploy competitive services in a rapid and cost-effective manner. To achieve this goal, we first propose an automatic service composition model relying on an IMS/Web converged environment. This service composition model is intended to be one in which even non-professional users can easily reuse existing services to create new services. To further improve the automatic service composition feature, three strategies including passive update, active update and hybrid update are proposed and analyzed. We then propose a centralized service exposure framework for a variey of services, including Telecom / Web / Device / user-generated services. This framework aims at enhancing the user-centric and convergence features, and providing the unified access to diverse services.Subsequently, two P2P based service information sharing models are designed to complement the centralized service exposure model : i) A hierarchical P2P based model, which reuses Chord for guaranteeing the service discovery efficiency, meanwhile adopts the concept of abstract service publication and discovery for enabling the ambiguous services searching. ii) A triplex P2P overlay based model, which mainly targets the devices offered services. In this model, we use the gateways to delegate the devices residing in them for the global service exposure, and use a triplex overlay based architecture, which includes an underlying unstructured P2P layer, a Semantic Overlay Network (SON) based overlay and a service dependency overlay, for the service information sharing and discovery
73

A framework for Automatic Web Service Composition based on service dependency analysis

Omer, Abrehet Mohammed 11 July 2011 (has links) (PDF)
The practice of composing web services has received an increasing interest with the emerging application development architecture called Service Oriented Architecture (SOA). A web service composition can be done either manually or (semi-) automatically. Doing composition (semi-) automatically minimizes runtime problems that arise due to dynamic nature of runtime environments. However, the implementation of (semi-) automatic composition demands for the automation of a process model or a composition plan generation process. In addition, creating a composite service or applications from component services, that are developed and meant to work independently, causes unavoidable dependencies among the services involved. Consequently, in a composite service development, understanding, analyzing and tracking of such dependencies becomes important. This thesis views the process model generation sub-task of a service composition as a service dependency identifification and analysis problem. In this thesis, we propose a dependency based automatic process model generation methods. For this purpose, the following issues are explored. First, a top layer architecture with a composition engine is developed. The architecture gives a complete picture of dependency based automatic service composition. Second, the process model generation sub-task is formulated as a service dependency identification and analysis problem. Third, a two-stepped method for automatic process model generation, given a set of candidate web service descriptions, is proposed. The first step of the proposed approach deals with the identifification of potential direct and indirect dependencies between abstract services. The direct dependency extraction is done by assuming a semantic I/O matching of service parameters. The extraction of indirect dependency from direct dependency is done using a recursive algorithm derived from the transitive closure property. Alternatively the Warshall algorithm is used. The second step of the proposed approach deals with analysis of dependency information and generation of process model (PM) automatically. To execute this step, we propose two approaches: matrix based and graph based approaches. The matrix based approach utilizes both direct and indirect dependencies. This approach represents dependencies using matrix and takes advantages of a sorting algorithm. The matrix representation facilitates a simplistic mathematical dependency analysis for generating important indicators during automatic process model creation. The process model is generated using a sorting algorithm that uses the analysis result obtained from the dependency matrix as sorting criterion. The graph based approach uses only direct dependency among candidate services. As its name indicates, in this approach the extracted I/O dependencies are represented using a directed graph. A modifified topological sorting algorithm is used for generating a process model that shows the execution order of candidate services. Both of the proposed approaches (matrix and graph based approaches) recognize the existence of cyclic dependencies and provide ways of dealing with them. The resulting process model or composition plan from both approaches has a sequential, concurrent and loop control flows. Finally, the performance of the proposed approaches is studied theoretically as well as experimentally. For the experimental validation and evaluation purpose, the approaches are implemented in a prototype that facilitates the validation and evaluation of the approaches at a larger scale. An extensive experimental performance evaluation is done fifirst on each proposed approach. The two approaches are then compared and their pros and cons under difffferent scenarios are assessed.
74

Desenvolvimento de aplicações usando composição de serviços dirigida pelo usuário

Guido, Alex Roberto 14 September 2016 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-01-16T10:24:44Z No. of bitstreams: 1 DissARG.pdf: 3218861 bytes, checksum: 52a9961c02ff8f02866be4a0e7c3462a (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2017-01-17T12:59:21Z (GMT) No. of bitstreams: 1 DissARG.pdf: 3218861 bytes, checksum: 52a9961c02ff8f02866be4a0e7c3462a (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2017-01-17T12:59:28Z (GMT) No. of bitstreams: 1 DissARG.pdf: 3218861 bytes, checksum: 52a9961c02ff8f02866be4a0e7c3462a (MD5) / Made available in DSpace on 2017-01-17T12:59:35Z (GMT). No. of bitstreams: 1 DissARG.pdf: 3218861 bytes, checksum: 52a9961c02ff8f02866be4a0e7c3462a (MD5) Previous issue date: 2016-09-14 / Não recebi financiamento / One of the Software Engineering challenges is the development of applications that can adapt to the heterogeneous needs of users. Technical Dynamic Composition of Services Driven by User is a solution for developing applications capable of overcoming these challenges. This type of application which will call User-Driven Service Composition Application (UDSCA) allows to compose services during its execution, thus meeting the needs of users. But the lack of guidance on how to develop UDCAs can make it difficult or even impossible to build these applications, because it may aggregate unknown solutions by developers. Looking supply this lack, this work presents an approach to guide developers during the development of this kind of application. To develop the approach, it has been defined which activities should be undertaken during the development as well as the concepts, techniques, artifacts, technologies and tools needed to perform these activities. To evaluate the approach one conducted a case study in which a UDSCA was developed in the field of building maintenance services. The resulting application of the approach was shown to be able to adapt to the heterogeneous needs of the user, also the approach provided artifacts that promoted reuse. In conclusion, the approach guides the developer during the UDSCAs development and provides artifacts that reduce efforts for development. / Um dos desafios da Engenharia de Software é o desenvolvimento de aplicações capazes de adaptar-se às diferentes necessidades dos usuários. A técnica de Composição Dinâmica de Serviços Dirigida pelo Usuário é uma solução para desenvolver aplicações capazes de superar esses desafios. Esse tipo de aplicação, a qual denominaremos User-Driven Service Composition Application (UDSCA), permite compor serviços durante sua execução, satisfazendo assim às necessidades dos usuários. Porém a falta de orientação em como desenvolver UDSCAs pode dificultar ou mesmo impossibilitar a construção dessas aplicações, pelo fato de agregar soluções que possam ser desconhecidas pelos desenvolvedores. Procurando suprir essa falta, este trabalho apresenta uma abordagem capaz de orientar os desenvolvedores durante o desenvolvimento deste tipo de aplicação. Na abordagem foram definidas quais as atividades devem ser realizadas durante o desenvolvimento deste tipo de aplicação, assim como os conceitos, técnicas, artefatos, tecnologias e ferramentas necessárias para realizar essas atividades. Para avaliar a abordagem foi realizado um estudo de caso que compreende o desenvolvimento de uma UDSCA no domínio de serviços urbanos. A aplicação resultante da abordagem mostrou-se capaz de adaptar-se às necessidades heterogêneas dos usuários. Além disso, a abordagem forneceu artefatos que promoveram o reuso. Concluiu-se assim que a abordagem orienta os desenvolvedores durante o desenvolvimento de UDSCAs e fornece artefatos que reduzem esforços durante esse desenvolvimento.
75

PEWS-RT, um sistema de tempo de execu??o para a linguagem PEWS / Web services. Service composition. PEWS. Runtime systems

Medeiros, Handerson Bezerra 17 July 2013 (has links)
Made available in DSpace on 2015-03-03T15:47:47Z (GMT). No. of bitstreams: 1 HandersonBM_DISSERT.pdf: 2503077 bytes, checksum: f08293a045825a9e00bb41506f0ef6e5 (MD5) Previous issue date: 2013-07-17 / Web services are loosely coupled applications that use XML documents as a way of integrating distinct systems on the internet. Such documents are used by in standards such as SOAP, WSDL and UDDI which establish, respectively, integrated patterns for the representation of messages, description, and publication of services, thus facilitating the interoperability between heterogeneous systems. Often one single service does not meet the users needs, therefore new systems can be designed from the composition of two or more services. This which is the design goal behind the of the Service Oriented Architecture. Parallel to this scenario, we have the PEWS (Predicate Path-Expressions for Web Services) language, which speci es behavioural speci cations of composite web service interfaces.. The development of the PEWS language is divided into two parts: front-end and back-end. From a PEWS program, the front-end performs the lexical analysis, syntactic and semantic compositions and nally generate XML code. The function of the back-end is to execute the composition PEWS. This master's dissertation work aims to: (i) reformulate the proposed architecture for the runtime system of the language, (ii) Implement the back-end for PEWS by using .NET Framework tools to execute PEWS programs using the Windows Work ow Foundation / Servi?os web s?o aplica??es de baixo acoplamento que utilizam documentos XML como forma de integra??o de sistemas heterog?neos. Tais documentos s?o usados em especi fica??es como SOAP, WSDL e UDDI que estabelecem, respectivamente, padr?es integrados para a representa??o de mensagens, descri??o e publica??o de servi?os, facilitando assim, a interoperabilidade de sistemas heterog?neos. Muitas vezes um s? servi?o n?o atende ?s necessidades dos usu?rios, portanto, novos sistemas podem ser concebidos a partir da composi??o de dois ou mais servi?os, motivando o desenvolvimento da SOA - arquitetura orientada a servi?os.Paralelo a esse cen?rio, tem-se a linguagem PEWS (Predicate path-Expres-sions for Web Services), que especifi ca o comportamento de como opera??es de servi?os web s?o executadas em uma composi??o de servi?os. O desenvolvimento da linguagem PEWS ? dividido em duas partes: front-end e back-end. A partir de um programa PEWS, o front-end realiza a an?lise l?xica, sint?tica e sem?ntica das composi??es e por m gera c?digo XML. O backend tem como fun??o executar a composi??o PEWS. Este trabalho visa: (i) Implementar o back-end de PEWS mediante o uso de ferramentas do .Net Framework para executar programas PEWS usando a tecnologia Windows Work ow Foundation (ii) reformular a arquitetura proposta para o sistema de tempo de execu??o da linguagem.
76

Composing DaaS web services : application to eHealth / Composition des services web DaaS : application à l'eSanté

Barhamgi, Mahmoud 08 October 2010 (has links)
Dans cette thèse, nous intéressons à l'automatisation de la composition de service Web d'accès aux données (i.e. DaaS Data-gs-g-S..ervice Web services) pour les besoins de partage de données dans les environnements distribués. La composition de service Web permet de répondre aux besoins d'un utilisateur ne pouvant être satisfaits par un seul Web service, alors qu'une intégration de plusieurs le permettrait. La motivation principale de notre travail est que les méthodes de composition, telles qu'elles sont appliquées aux services Web traditionnels (i.e. AaaS Application-as-a-Service Web services), ne permettent pas de prendre en compte la relation sémantique entre les entrées/sorties d'un service Web d'accès aux données, et en conséquence, elles ne sont pas adaptées pour composer les services Web d'accès aux données. Dans ce travail de thèse, nous proposons d'exploiter les principes de base des systèmes d'intégration des données pour composer les services Web d'accès aux données. Plus précisément, nous modélisons les services Web d'accès aux données comme des vues sur des ontologies de domaine. Cela permet de représenter la sémantique d'un service d'une manière déclarative en se basant sur des concepts et des relations dont les sémantiques sont formellement définies dans l'ontologie de domaine. Ensuite, nous utilisons les techniques de réécriture des requêtes pour sélectionner et composer automatiquement les services pour répondre aux requêtes des utilisateurs. Comme les services Web d'accès aux données peuvent être utilisés pour accéder à des données sensibles et privées, nous proposons également un mécanisme basé sur la modification des requêtes pour préserver la confidentialité des données. Ce mécanisme modifie les requêtes en se basant sur des politiques de confidentialité avant leur résolution par 1' algorithme de composition, et il prend en considération les préférences des utilisateurs quant à la divulgation de leurs données privées. Le principal domaine d'application de notre approche est le domaine d'e-santé, où les services Web d'accès aux données sont utilisés pour partager les dossiers médicaux des patients. / In this dissertation, we propose a novel approach for the automatic composition of DaaS Web services (DaaS Data-gs-g-S.ervice Web services). Automatic DaaS Web service composition requires dealing with three major research thrusts: (i) describing the semantics of DaaS Web services, (ii) selecting and combining relevant DaaS Web services, and (iii) generating composite service descriptions (i.e. the compositions' plans). We first propose to model DaaS Web services as RDF views over domain ontologies. An RDF view allows capturing the semantics of the associated DaaS Web service in a "declarative" way based on concepts and relationships whose semantics are formally defined in domain ontologies. The service description files (i.e. WSDL files) are annotated with the defined RDF views using the extensibility feature of the WSDL standard. We then propose to use query rewriting techniques for selecting and composing DaaS Web services. Specifically, we devised an efficient RDF-oriented query rewriting algorithm that selects relevant services based ontheir defined RDF views and combines them to ans~wer a posed query. It also generates an execution plan for the obtained composition/s. Our algorithm takes into account the RDFS semantic constraints (i.e. "subClassOf", "subPropertyOf", "Domain" and "Range") and is able to address both specifie and parameterized queries. Since DaaS Web services may be used to access sensitive and private data; we also extended our DaaS service composition approach to handle data privacy concems. Posed queries are modified to accommodate pertaining privacy conditions from data privacy policies before their resolution by the core composition algorithm. Our proposed privacy preservation model takes user' s privacy preferences into account.
77

COMPOSIÇÃO DINÂMICA DE SERVIÇOS WEB SEMÂNTICOS UTILIZANDO ABORDAGENS DA ENGENHARIA DIRIGIDA POR MODELOS / DYNAMIC COMPOSITION OF SEMANTIC WEB SERVICES USING APPROACHES OF ENGINEERING DIRECTED BY MODELS

BEZERRA, Eduardo Devidson Costa 29 July 2011 (has links)
Made available in DSpace on 2016-08-17T14:53:18Z (GMT). No. of bitstreams: 1 Eduardo Devidson Costa Bezerra.pdf: 6161794 bytes, checksum: 61fa31f8c5757b2b771df924fa5e9483 (MD5) Previous issue date: 2011-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of the Internet as a way to publish new applications and deliver new functionalities has consolidated the use of web services technology. Once web services technology enables a high degree of autonomy and interoperability, it provides a basic infrastructure for the development and composition of new services, which has benefited the business process management providing the agility required by enterprises to meet the need of rapidly changing business environment. Recently, new paradigms are being developed to deal with the increasing complexity in the development, maintenance and evolution of software systems. Among the new paradigms, Model Driven Engineering (MDE) and the Ontology stands out as the most promising for handling complex software systems. This work presents an approach to perform the dynamic composition of web services using techniques of match models (metamodels) that represent services. Models representing services must include semantic and structural aspects of the web service achieved through approaches to ontologies. Thus, we conjecture to establish matchings and measure the degree of similarity between models and investing in research about Ontologies and MDE in order to generate a tool that can assist in a Dynamic Composition of Web Services. A case study is presented to illustrate this approach. / A utilização da internet como forma de publicar novas aplicações e disponibilizar novas funcionalidades tem consolidado o uso da tecnologia de serviços web. Uma vez que essa tecnologia viabiliza um alto grau de interoperabilidade e autonomia, a tecnologia de serviços web fornece uma infra-estrutura básica para o desenvolvimento e a composição de novos serviços, o que tem beneficiado à gerência de processos de negócio oferecendo assim, a agilidade necessária e requerida pelos empreendimentos frente à necessidade de rápidas mudanças no ambiente de negócios. Recentemente, novos paradigmas vêm sendo desenvolvidos para fazerem face à complexidade cada vez mais crescente no desenvolvimento, manutenção e evolução de softwares. Dentre eles a Engenharia Dirigida por Modelos (MDE Model Driven Engineering) e as Ontologias se destacam como os mais promissores. Neste trabalho, apresenta-se uma abordagem para realizar a composição dinâmica de um novo serviço web utilizando técnicas de Matching de modelos (ou metamodelos) que representem serviços. Tal representação deverá conter aspectos semânticos e estruturais do serviço web conseguidos através de abordagens de Ontologias. Sendo assim, vislumbra-se estabelecer correspondências e medir o grau de similaridade entre modelos investindo na pesquisa de MDE e Ontologias com o intuito de gerar uma ferramenta que possa auxiliar na Composição Dinâmica de um Serviço. Para validar a abordagem, um estudo de caso será apresentado.
78

Pervasive service computing: community coordinated multimedia, context awareness, and service composition

Zhou, J. (Jiehan) 22 November 2011 (has links)
Abstract This thesis introduces a novel Web service-centric solution to pervasive computing, called Service-oriented Pervasive Computing (also called Pervasive Service Computing), which enables computer systems to deal with context in the user’s environment, to dynamically discover and compose existing services, and to develop Internet-scale multimedia applications that support users’ activities. First, this thesis introduces the concept of Pervasive Service Computing and its relation to community coordinated multimedia, context awareness, and service-oriented computing. It then investigates the state of the art, the practices, and techniques which have been developed to support such services. Building on these tools, this study adopts a service-oriented methodology to design a reference model for Pervasive Service Computing, for accommodating specified technical requirements. This model can serve as a guide for research and development towards Pervasive Service Computing. Second, the thesis examines the nature of community coordinated multimedia, and develops the concept of Community Coordinated Multimedia (CCM). To discover the potentials of discoverability and composability of multimedia applications, the thesis introduces a model for Service-oriented Community Coordinated Multimedia (SCCM), and demonstrates the idea of “multimedia application as a service.” Furthermore, the thesis presents a content annotation service and evaluates its feasibility as an end-user prototype. Third, the thesis investigates the nature of context awareness in Pervasive Service Computing, to broaden the definition of context and context-awareness. This research introduces context-aware pervasive service composition (CAPSC) applications, and specifies three-levels of context awareness. Building on this framework, the context-aware service composition prototype is implemented. Fourth, the author examines the overall potential of service composition in Pervasive Service Computing, distinguishes its two main functions as service collaboration, and service coordination, and then develops an ODPSC (Ontology-Driven Pervasive Service Composition) ontology. To address the availability and scalability of service composition, the thesis introduces options for dynamic service composition in the Cloud, and develops an accelerated Cloud architecture for service composition in the Cloud (namely CM4SC middleware). Last, the CM4SC middleware as a service prototype is implemented. / Tiivistelmä Tässä työssä käsitellään uutta jokapaikan tietotekniikan Web-palvelukeskeistä ratkaisua, palveluorientoitunutta jokapaikan tietotekniikkaa (Pervasive Service Computing). Tämän avulla tietokonejärjestelmät voivat ottaa huomioon käyttäjän ympäristön tilanteen, löytää ja koota palveluja dynaamisesti, ja näin voidaan kehittää Internetin laajuisia käyttäjän toimintoja tukevia multimediasovelluksia. Ensiksi työssä esitellään jokapaikan tietotekniikan palvelujen käsite sekä tällaisten palveluiden suhde yhteisöllisesti koordinoituun multimediaan, tilannetietoisuuten ja palveluorientoituneeseen tietotekniikkaan. Tieteen nykytila sekä tällaisia palveluja tukemaan kehitetyt käytännöt ja tekniikat esitellään. Näihin työkaluihin pohjautuen työssä omaksutaan palveluorientoitunut metodiikka, kun jokapaikan tietotekniikan palveluille suunnitellaan referenssimalli, jonka avulla voidaan määritellä teknisiä vaatimuksia ja joka voi muutenkin toimia ohjenuorana jokapaikan tietotekniikan palvelujen tutkimukselle ja tuotekehitykselle. Toiseksi työssä tutkitaan yhteisöllisesti koordinoidun multimedian ominaispiirteitä ja määritellään yhteisöllisesti koordinoidun multimedian (Community Coordinated Multimedia, CCM) käsite. Multimediasovellusten löydettävyyden ja kokoamisen mahdollisuuksien kartoittamiseen luodaan palveluorientoitunut CCM-malli (Service-oriented Community Coordinated Multimedia, SCCM). Työssä esitellään ”multimediasovellus palveluna” -idea, jonka käyttökelpoisuutta arvioidaan sisältöpohjaisen annotoinnin prototyyppiratkaisun avulla. Kolmanneksi työssä tutkitaan jokapaikan tietotekniikan palvelujen tilannetietoisuutta laajentamalla tilanteen ja tilannetietoisuuden määritelmiä. Tutkimus esittelee tilannetietoiseen jokapaikan tietotekniikan palvelujen kokoamiseen (Context-Aware Pervasive Service Composition, CAPSC) perustuvia sovelluksia ja määrittelee kolme tasoa tilannetietoisuudelle. Tämän viitekehyksen avulla toteutetaan tilannetietoinen palvelujen kokoamisen prototyyppi. Neljänneksi työssä arvioidaan jokapaikan tietotekniikan palvelujen kokoamisen mahdollisuuksia, tunnistetaan sen kaksi keskeistä toiminnallisuutta, palvelujen yhteistoiminnallisuus (service collaboration) ja palvelujen koordinointi (service coordination), sekä kehitetään ODPSC (Ontology-Driven Pervasive Service Composition) -ontologia. Työssä esitetään saavutettavuuden ja laajennettavuuden haasteisiin ratkaisuksi dynaaminen palvelujen kokoaminen pilvipalveluna. Työssä kehitetään kiihdytetty pilviarkkitehtuuri (CM4SC-välikerrosohjelmisto) palvelujen kokoamiseen pilvessä. Lopuksi työssä toteutetaan CM4SC-välikerrosohjelmiston palveluprototyyppi.
79

Une approche ontologique pour l'interopérabilité et la composition automatique de services Web : application en astrophysique / An ontologial approach for interoperability and automatic composition of Web services : application to astrophysics

Louge, Thierry 05 July 2017 (has links)
Dans le but d’exploiter au mieux les grandes masses de données hétérogènes produites par les instruments scientifiques modernes de l’astrophysique, les scientifiques ont développé le concept d’Observatoire Virtuel (OV). Il s’agit d’une architecture orientée services, qui a pour objectif de faciliter l’identification et l’interopérabilité des données astrophysiques. Malgré le développement et les avancées permises par l’OV dans l’exploitation de ces données, certains objectifs sont partiellement atteints notamment l’interopérabilité, la sélection de services et l’identification de services connexes, etc. Par ailleurs, l’ergonomie des outils à la disposition de l’utilisateur final reste perfectible. De même l’utilisation actuelle des ressources de l’OV, s’appuyant sur des compétences humaines, gagnerait à être automatisée. Les services de données astrophysiques n’étant pas tous inscrits dans l’OV, il serait aussi souhaitable pour permettre une utilisation plus large de ces outils, qu’ils s’appuient également sur des services disponibles en-dehors de l’OV. En vue d’automatiser l’utilisation des ressources en ligne, les sciences de l’information travaillent depuis 2001 à l’élaboration du Web sémantique. Cette évolution apporte au Web des capacités de raisonnement automatiques, basées sur des algorithmes utilisant une nouvelle forme de description des contenus. Cette nouvelle forme de description sémantique se trouve exprimée dans des représentations informatiques appelées ontologies. Malheureusement, les méthodes actuelles d’élaboration du Web sémantique ne sont pas complètement compatibles avec les services OV qui utilisent des modèles de données, des formats et des protocoles d’accès aux services qui s’éloignent de ceux rencontrés habituellement dans les sciences de l’information. Dans ce contexte, cette thèse décrit une méthodologie générique de composition de services sans état, basée sur la description des services par une ontologie dont la définition est proposée dans ce document. Cette ontologie représente aussi bien des services Web que des services non accessibles par le Web. Elle prend en compte certaines spécificités qui peuvent être rencontrées dans les infrastructures de services préexistantes. L’enrichissement de l’ontologie par des concepts issus de domaines d’application spécifiques pour lesquels il n’existe que peu de représentations ontologiques est également pris en compte. La population de cette ontologie, par des services éventuellement éloignés des standards utilisés habituellement dans les sciences de l’information, est aussi traitée. La méthodologie a été appliquée avec succès dans le cadre de l’astrophysique, et a permis de développer une application Web permettant la composition automatique de services utilisable par un public non averti. / Scientists have developed the Virtual Observatory (VO) concept in order to make the most of the large masses of heterogeneous data produced by the modern scientific instruments of astrophysics. It is a service-oriented architecture, aiming to facilitate the identification and interoperability of astrophysical data. Despite the development and advances made by VO in the exploitation of these data, some objectives are partially such as interoperability, service selection and identification of related services, etc. In addition, the ergonomics of the tools available to the end user can be improved. Similarly, the current use of VO resources, based on human skills, would benefit from being automated. As not all the astrophysical data services are included in the VO, it would also be desirable to allow a wider use of these tools, as they also rely on services available outside the VO. In order to automate the use of online resources, information sciences have been working since 2001 on the development of the Semantic Web. This evolution provides the Web with automatic reasoning abilities, based on algorithms using a new form of content description. This new form of semantic description is expressed in computer representations called ontologies. Unfortunately, the current semantic Web development methods are not fully compatible with VO services that use data models, formats and protocols for accessing services that differ from those typically encountered in information sciences. In this context, this thesis describes a generic methodology for the composition of stateless services, based on the description of services by a global ontology, the definition of which is proposed in this document. This ontology represents both Web services and services that are not accessible via the Web. It takes into account certain specificities that may be encountered in preexisting service infrastructures. The enrichment of the ontology by concepts derived from specific fields of application for which there are only a few ontological representations is also taken into account. The population of this ontology, by services possibly distant from the standards usually used in the information sciences, is also treated. The methodology was applied successfully in the framework of astrophysics, and allowed to develop a Web application allowing the automatic composition of services usable by an uninformed public.
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Využití systému SAP v kompozici business služeb / Using of SAP System in Business Services Composition

Simetinger, František January 2011 (has links)
This thesis is focused on service in frame of enterprise computing and composition of these services. This brings a number of issues in large spectra of perspectives and this thesis has the ambition these issues resolve. The goal of this thesis is considering the principles application of service oriented architecure and standard methodologies in composition of internally managed by process complex business service, which composes services in SAP information system and which use resources of IBM WebSphere Process Server and IBM WebSphere ESB Server. The basic presumption to goal achieve is precise identification and definition of service. Also important is the notion of composition. So what are especially logical links between services. Based on this service identification it is going to be clarified the options of its composition and it is going to be specified the importance of service definition and composition in enterprise computing area. After defining the services in computing context the thesis is going to be focused on composite business services. Composite business services are going to be analyzed from three perspectives: Engineering, Management and Governance. The benefit of thesis is answer to question if it is possible in specific environment with specific conditions to compose business services, which respect the criterions of three perspectives: Engineering, Management and Governance. If the composition of those business services will respect generally respected standards and recommendations in a defined environment. Thesis in its structure passes from general knowledge about services to knowledge about services in frame of enterprise computing. This knowledge is based on analysis and recommendations of methodologies which are focused on service oriented IT management. Knowledge of this analysis are became basis for definition of three perspectives. Principles defined in three perspectives are going to be verified in real experiment.

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