The World Wide Web is an infrastructure to publish and retrieve information through web resources. It evolved from a static Web 1.0 to a multimodal and interactive communication and information space which is used to collaboratively contribute and discuss web resources, which is better known as Web 2.0. The evolution into a Semantic Web (Web 3.0) proceeds. One of its remarkable advantages is the decentralized and interlinked data composition. Hence, in contrast to its data distribution, workflows and technologies for decentralized collaborative contribution are missing. In this paper we propose the Structured Feedback protocol as an interactive addition to the Web of Data. It offers support for users to contribute to the evolution of web resources, by providing structured data artifacts as patches for web resources, as well as simple plain text comments. Based on this approach it enables crowd-supported quality assessment and web data cleansing processes in an ad-hoc fashion most web users are familiar with.

Orientador: Frank José Affonso / Resumo: O cenário atual de desenvolvimento de software tem revelado um uso crescente de aplicações baseadas em serviços. Em um ambiente de computação distribuída, monitorar a qualidade de serviços para que essa aplicação não apresente algum tipo de anomalia ou interrupção pode ser considerada uma tarefa vital. Para isso, é necessário prover meios para o desenvolvimento de sistemas baseados em serviços capazes de observar seu estado interno de execução e/ou contexto ao qual estão inseridos e reagir diante de mudanças ou algum tipo de imprevisibilidade. Aplicações orientadas a serviços que permitem adaptação em tempo de execução podem ser classificadas como Self-Apps (do inglês, Self-adaptive Service-oriented Applications). Em função da complexidade intrínseca a esse tipo de aplicação, o uso de frameworks tem se mostrado uma alternativa viável por aliviar a carga cognitiva de desenvolvimento, a qual envolve o conhecimento de diversas áreas de pesquisa. Motivado por esse cenário, durante a realização deste trabalho foi conduzida uma revisão da literatura que engloba a condução de um mapeamento sistemático e consultas complementares em bases nacionais de teses e dissertações. Essa revisão permitiu obter um panorama detalhado referente ao estágio atual da pesquisa, seus desafios e as perspectivas futuras sobre frameworks para Self-Apps. Embasado nos resultados dessa revisão, o objetivo deste trabalho é o desenvolvimento do framework DynaMS (do inglês, Dynamic Deployment, QoS Metrics and S... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The current software development scenario has shown a crescent usage of service-based applications. In a distributed computing environment, the monitoring of the service’s quality is a relevant task because aims to assure that it does not present any anomaly or interruption. To do so, it is necessary to provide means to develop service-based systems that are capable to observe their internal execution state and/or the context in which they are inserted and to react in face of changes or unforeseen circumstances. Service-oriented applications that are able to perform adaptation in runtime can be classified as Self-Apps (i.e., Self-adaptive Service-oriented Applications). Given the complexity involved in this type of application, the use of frameworks has been shown as a viable alternative to reduce the cognitive development load regarding the knowledge from different research areas. Motivated by this scenario, we conducted a literature review as a part of this work. This review includes a systematic mapping and complementary searches to national thesis and dissertations’ databases. This review provided us a detailed panorama about the current stage of research, its challenges and the future perspectives regarding frameworks for Self-Apps. Based on the results from this review, the purpose of this Master’s project is to present a framework called DynaMS (Dynamic Deployment, QoS Metrics and Semantic Search) to support the development of this type of application. In short, this f... (Complete abstract click electronic access below) / Mestre

The need for modern enterprises and Web users to simply and rapidly develop and deliver platform-independent services to be accessed over the Web by the global community is growing. This is self-evident, when one considers the omnipresence of electronic services (e-services) on the Web. Accordingly, the Service-Oriented Architecture (SOA) is commonly considered as one of the de facto standards for the provisioning of heterogeneous business functionalities on the Web. As the basis for SOA, Web Services (WS) are commonly preferred, particularly because of their ability to facilitate the integration of heterogeneous systems. However, WS only focus on syntactic descriptions when describing the functional and behavioural aspects of services. This makes it a challenge for services to be automatically discovered, selected, composed, invoked, and executed – without any human intervention. Consequently, Semantic Web Services (SWS) are emerging to deal with such a challenge. SWS represent the convergence of Semantic Web (SW) and WS concepts, in order to enable Web services that can be automatically processed and understood by machines operating with limited or no user intervention. At present, research efforts within the SWS domain are mainly concentrated on semantic services automation aspects, such as discovery, matching, selection, composition, invocation, and execution. Moreover, extensive research has been conducted on the conceptual models and formal languages used in constructing semantic services. However, in terms of the engineering of semantic services, a number of challenges are still prevalent, as demonstrated by the lack of development and use of semantic services in real-world settings. The lack of development and use could be attributed to a number of challenges, such as complex semantic services enabling technologies, leading to a steep learning curve for service developers; lack of unified service platforms for guiding and supporting simple and rapid engineering of semantic services, and the limited integration of semantic technologies with mature service-oriented technologies. vi In addition, a combination of isolated software tools is normally used to engineer semantic services. This could, however, lead to undesirable consequences, such as prolonged service development times, high service development costs, lack of services re-use, and the lack of semantics interoperability, reliability, and re-usability. Furthermore, available software platforms do not support the creation of semantic services that are intelligent beyond the application of semantic descriptions, as envisaged for the next generation of services, where the connection of knowledge is of core importance. In addressing some of the challenges highlighted, this research study adopted a qualitative research approach with the main focus on conceptual modelling. The main contribution of this study is thus a framework called iSemServ to simplify and accelerate the process of engineering intelligent semantic services. The framework has been modelled and developed, based on the principles of simplicity, rapidity, and intelligence. The key contributions of the proposed framework are: (1) An end-to-end and unified approach of engineering intelligent semantic services, thereby enabling service engineers to use one platform to realize all the modules comprising such services; (2) proposal of a model-driven approach that enables the average and expert service engineers to focus on developing intelligent semantic services in a structured, extensible, and platform-independent manner. Thereby increasing developers’ productivity and minimizing development and maintenance costs; (3) complexity hiding through the exploitation of template and rule-based automatic code generators, supporting different service architectural styles and semantic models; and (4) intelligence wrapping of services at message and knowledge levels, for the purposes of automatically processing semantic service requests, responses and reasoning over domain ontologies and semantic descriptions by keeping user intervention at a minimum. The framework was designed by following a model-driven approach and implemented using the Eclipse platform. It was evaluated using practical use case scenarios, comparative analysis, and performance and scalability experiments. In conclusion, the iSemServ framework is considered appropriate for dealing with the complexities and restrictions involved in engineering intelligent semantic services, especially because the amount of time required to generate intelligent semantic vii services using the proposed framework is smaller compared with the time that the service engineer would need to manually generate all the different artefacts comprising an intelligent semantic service. Keywords: Intelligent semantic services, Web services, Ontologies, Intelligent agents, Service engineering, Model-driven techniques, iSemServ framework. / Computing / D. Phil. (Computer science)

The need for modern enterprises and Web users to simply and rapidly develop and deliver platform-independent services to be accessed over the Web by the global community is growing. This is self-evident, when one considers the omnipresence of electronic services (e-services) on the Web. Accordingly, the Service-Oriented Architecture (SOA) is commonly considered as one of the de facto standards for the provisioning of heterogeneous business functionalities on the Web. As the basis for SOA, Web Services (WS) are commonly preferred, particularly because of their ability to facilitate the integration of heterogeneous systems. However, WS only focus on syntactic descriptions when describing the functional and behavioural aspects of services. This makes it a challenge for services to be automatically discovered, selected, composed, invoked, and executed – without any human intervention. Consequently, Semantic Web Services (SWS) are emerging to deal with such a challenge. SWS represent the convergence of Semantic Web (SW) and WS concepts, in order to enable Web services that can be automatically processed and understood by machines operating with limited or no user intervention. At present, research efforts within the SWS domain are mainly concentrated on semantic services automation aspects, such as discovery, matching, selection, composition, invocation, and execution. Moreover, extensive research has been conducted on the conceptual models and formal languages used in constructing semantic services. However, in terms of the engineering of semantic services, a number of challenges are still prevalent, as demonstrated by the lack of development and use of semantic services in real-world settings. The lack of development and use could be attributed to a number of challenges, such as complex semantic services enabling technologies, leading to a steep learning curve for service developers; lack of unified service platforms for guiding and supporting simple and rapid engineering of semantic services, and the limited integration of semantic technologies with mature service-oriented technologies. vi In addition, a combination of isolated software tools is normally used to engineer semantic services. This could, however, lead to undesirable consequences, such as prolonged service development times, high service development costs, lack of services re-use, and the lack of semantics interoperability, reliability, and re-usability. Furthermore, available software platforms do not support the creation of semantic services that are intelligent beyond the application of semantic descriptions, as envisaged for the next generation of services, where the connection of knowledge is of core importance. In addressing some of the challenges highlighted, this research study adopted a qualitative research approach with the main focus on conceptual modelling. The main contribution of this study is thus a framework called iSemServ to simplify and accelerate the process of engineering intelligent semantic services. The framework has been modelled and developed, based on the principles of simplicity, rapidity, and intelligence. The key contributions of the proposed framework are: (1) An end-to-end and unified approach of engineering intelligent semantic services, thereby enabling service engineers to use one platform to realize all the modules comprising such services; (2) proposal of a model-driven approach that enables the average and expert service engineers to focus on developing intelligent semantic services in a structured, extensible, and platform-independent manner. Thereby increasing developers’ productivity and minimizing development and maintenance costs; (3) complexity hiding through the exploitation of template and rule-based automatic code generators, supporting different service architectural styles and semantic models; and (4) intelligence wrapping of services at message and knowledge levels, for the purposes of automatically processing semantic service requests, responses and reasoning over domain ontologies and semantic descriptions by keeping user intervention at a minimum. The framework was designed by following a model-driven approach and implemented using the Eclipse platform. It was evaluated using practical use case scenarios, comparative analysis, and performance and scalability experiments. In conclusion, the iSemServ framework is considered appropriate for dealing with the complexities and restrictions involved in engineering intelligent semantic services, especially because the amount of time required to generate intelligent semantic vii services using the proposed framework is smaller compared with the time that the service engineer would need to manually generate all the different artefacts comprising an intelligent semantic service. Keywords: Intelligent semantic services, Web services, Ontologies, Intelligent agents, Service engineering, Model-driven techniques, iSemServ framework. / Computing / D. Phil. (Computer science)

Made available in DSpace on 2014-07-29T14:57:49Z (GMT). No. of bitstreams: 1 Dissertacao Otavio C Xavier.pdf: 2295906 bytes, checksum: f43ea2a633498324e92187e3bd263ab4 (MD5) Previous issue date: 2011-09-26 / The researches on Semantic Web Services are aimed, mostly, the SOAP architecture. This architecture is rarely used in Web 2.0 and therefore in Online Social Networks. This dissertation presents an approach for practical implementation of semantic descriptions in RESTfulWeb Services. It is a simplified architecture that gained much focus onWeb 2.0, increasingly replacing the SOAP architecture. The development of the tool, presented here, will fill a gap in the process of implanting the Semantic Web. Existing solutions expose a theoretical view and have no practical implementations. The solution proposed in this paper, relates existing standards and technologies to develop an integrated and free tool. From which, services of a popular Online Social Network are described. Finally, the automatic discovery, composition and invocation of such services are made. / As pesquisas acerca de Serviços Web Semânticos são voltadas, em sua grande maioria, à arquitetura SOAP. Esta arquitetura é pouco utilizada na Web 2.0 e, logo, em Redes Sociais Online. Este trabalho apresenta uma abordagem para implementação prática de descrição semântica em Serviços Web, baseados na arquitetura REST. Trata-se de uma arquitetura simplificada e que ganhou muito enfoque na Web 2.0, substituindo cada vez mais a arquitetura SOAP. O desenvolvimento da ferramenta, apresentada aqui, poderá preencher uma lacuna no processo de implantação da Web Semântica. As soluções existentes expõem uma visão teórica do assunto e não possuem implementações práticas. A solução proposta neste trabalho, relaciona padrões e tecnologias já existentes para o desenvolvimento de uma ferramenta livre e integrada. A partir dela, serviços de uma Rede Social Online popular são descritos. Por fim, é mostrado como realizar a descoberta, composição e invocação automatizada de tais serviços.