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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.
1

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.
2

Certifica??o de composi??es de servi?os web sem?nticos

Pessini, Evando Carlos 29 July 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-20T20:41:23Z No. of bitstreams: 1 EvandoCarlosPessini_TESE.pdf: 1797248 bytes, checksum: e3b1bb46971f452029930068e9f8babf (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-21T18:18:20Z (GMT) No. of bitstreams: 1 EvandoCarlosPessini_TESE.pdf: 1797248 bytes, checksum: e3b1bb46971f452029930068e9f8babf (MD5) / Made available in DSpace on 2016-01-21T18:18:20Z (GMT). No. of bitstreams: 1 EvandoCarlosPessini_TESE.pdf: 1797248 bytes, checksum: e3b1bb46971f452029930068e9f8babf (MD5) Previous issue date: 2014-07-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Esta tese apresenta um m?todo de certifica??o de composi??es de servi?os web sem?nticos, o qual visa assegurar estaticamente sua corre??o funcional. O m?todo de certifica??o consiste em duas dimens?es de verifica??o, denominadas base e funcional. A dimens?o base ? centrada na verifica??o da correta aplica??o dos servi?os web sem?nticos na composi??o, i.e., visa certificar que as invoca??es de servi?o especificadas na composi??o est?o em conformidade com as respectivas defini??es dos servi?os. A certifica??o desta dimens?o explora a compatibilidade sem?ntica entre os argumentos dados na invoca??o e os par?metros formais do servi?o web sem?ntico. A dimens?o funcional visa certificar que a composi??o cumpre uma dada especifica??o expressa na forma de pr? e p?s-condi??es. Esta dimens?o ? formalizada atrav?s de um c?lculo baseado na l?gica de Hoare. Especifica??es de corre??o parciais envolvendo composi??es de servi?os web sem?nticos podem ser derivadas a partir do sistema dedutivo proposto. Este trabalho caracteriza-se tamb?m por explorar o emprego de um fragmento da l?gica descritiva, i.e., ALC, para expressar as especifica??es de corre??o parciais. Como forma de operacionalizar o m?todo de certifica??o, foi desenvolvido um ambiente de suporte para a defini??o das composi??es de servi?os web sem?nticos, assim como os mecanismos necess?rios para realizar a certifica??o. O m?todo de certifica??o foi avaliado experimentalmente atrav?s da aplica??o em tr?s provas de conceito diferentes. As provas de conceito desenvolvidas possibilitaram avaliar de forma ampla o m?todo de certifica??o proposto / This thesis presents a certification method for semantic web services compositions which aims to statically ensure its functional correctness. Certification method encompasses two dimensions of verification, termed base and functional dimensions. Base dimension concerns with the verification of application correctness of the semantic web service in the composition, i.e., to ensure that each service invocation given in the composition comply with its respective service definition. The certification of this dimension exploits the semantic compatibility between the invocation arguments and formal parameters of the semantic web service. Functional dimension aims to ensure that the composition satisfies a given specification expressed in the form of preconditions and postconditions. This dimension is formalized by a Hoare logic based calculus. Partial correctness specifications involving compositions of semantic web services can be derived from the deductive system proposed. Our work is also characterized by exploiting the use of a fragment of description logic, i.e., ALC, to express the partial correctness specifications. In order to operationalize the proposed certification method, we developed a supporting environment for defining the semantic web services compositions as well as to conduct the certification process. The certification method were experimentally evaluated by applying it in three different proof concepts. These proof concepts enabled to broadly evaluate the method certification
3

Cloud Stratus: uma plataforma de middleware para desenvolvimento de aplica??es em nuvem / Cloud Stratus: a middleware platform for development of cloud applications

Alves, Gustavo Nogueira 28 January 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-26T17:46:31Z No. of bitstreams: 1 GustavoNogueiraAlves_DISSERT.pdf: 7390589 bytes, checksum: 622ffc2952552ee8688415a6acdb97f1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-28T17:44:43Z (GMT) No. of bitstreams: 1 GustavoNogueiraAlves_DISSERT.pdf: 7390589 bytes, checksum: 622ffc2952552ee8688415a6acdb97f1 (MD5) / Made available in DSpace on 2016-01-28T17:44:43Z (GMT). No. of bitstreams: 1 GustavoNogueiraAlves_DISSERT.pdf: 7390589 bytes, checksum: 622ffc2952552ee8688415a6acdb97f1 (MD5) Previous issue date: 2015-01-28 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Computa??o em Nuvem ? um paradigma computacional que possibilita o acesso de forma simples e pervasiva, via rede, a recursos compartilhados e configur?veis de computa??o. Tais recursos s?o oferecidos sob demanda para o usu?rio atrav?s de um modelo de uso em que s? se paga pelo uso do recurso. Com o avan?o desse paradigma, um ?nico servi?o oferecido por uma plataforma de nuvem pode n?o ser suficiente para prover todos os requisitos dos clientes, sendo necess?rio uma composi??o de servi?os providos por diferentes plataformas de nuvem. No entanto, as plataformas de nuvem atuais n?o s?o implementadas usando padr?es comuns, cada uma possui sua pr?pria API e ferramenta de desenvolvimento, o que dificulta a cria??o da composi??o. Para facilitar a cria??o de composi??es existe o Cloud Integrator, uma plataforma de middleware orientada a servi?os que prov? um ambiente que facilita o desenvolvimento e a execu??o de aplica??es. Essas aplica??es s?o composi??es de servi?os de diferentes plataformas de nuvem e representadas atrav?s de workflows abstratos. No entanto, o Cloud Integrator possui algumas limita??es: (i) as aplica??es criadas s?o executadas localmente; (ii) usu?rios n?o podem especificar a aplica??o apenas pelas suas entradas e sa?das, e; (iii) os usu?rios n?o podem selecionar diretamente qual os servi?os que v?o executar as atividades do workflow. A fim de tratar essas limita??es, esse trabalho prop?e o Cloud Stratus, uma plataforma de middleware que estende o Cloud Integrator e oferece diferentes formas de especificar aplica??es, permitindo se definir um workflow abstrato ou fluxo de execu??o completo ou parcial. A plataforma possibilita a implanta??o da aplica??o em m?quinas virtuais na nuvem, de forma que v?rios usu?rios podem acess?-la atrav?s da Internet. O Cloud Stratus ainda realiza o acesso e gerenciamento de m?quinas virtuais de diferentes plataformas de nuvem e fornece mecanismos para monitoramento de servi?os e aferi??o de par?metros de QoS. A valida??o do Cloud Stratus ? realizada atrav?s de um estudo de caso que consiste de uma aplica??o que utiliza diversos servi?os de nuvem providos por diferentes plataformas de nuvem. O Cloud Stratus ainda ? avaliado atrav?s de experimentos computacionais que analisam o desempenho de seus processos. / Cloud Computing is a paradigm that enables the access, in a simple and pervasive way, through the network, to shared and configurable computing resources. Such resources can be offered on demand to users in a pay-per-use model. With the advance of this paradigm, a single service offered by a cloud platform might not be enough to meet all the requirements of clients. Ergo, it is needed to compose services provided by different cloud platforms. However, current cloud platforms are not implemented using common standards, each one has its own APIs and development tools, which is a barrier for composing different services. In this context, the Cloud Integrator, a service-oriented middleware platform, provides an environment to facilitate the development and execution of multi-cloud applications. The applications are compositions of services, from different cloud platforms and, represented by abstract workflows. However, Cloud Integrator has some limitations, such as: (i) applications are locally executed; (ii) users cannot specify the application in terms of its inputs and outputs, and; (iii) experienced users cannot directly determine the concrete Web services that will perform the workflow. In order to deal with such limitations, this work proposes Cloud Stratus, a middleware platform that extends Cloud Integrator and offers different ways to specify an application: as an abstract workflow or a complete/partial execution flow. The platform enables the application deployment in cloud virtual machines, so that several users can access it through the Internet. It also supports the access and management of virtual machines in different cloud platforms and provides services monitoring mechanisms and assessment of QoS parameters. Cloud Stratus was validated through a case study that consists of an application that uses different services provided by different cloud platforms. Cloud Stratus was also evaluated through computing experiments that analyze the performance of its processes.
4

Uma m?quina de redu??o de grafos extens?vel para a implementa??o de fluxos de trabalho / An extensible graph reduction machine for workflow implementation

Mac?do, M?rcio Alves de 26 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-22T21:43:01Z No. of bitstreams: 1 MarcioAlvesDeMacedo_DISSERT.pdf: 2923226 bytes, checksum: e6a66719b01ddee0f70ac0a7f964923e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-23T23:10:23Z (GMT) No. of bitstreams: 1 MarcioAlvesDeMacedo_DISSERT.pdf: 2923226 bytes, checksum: e6a66719b01ddee0f70ac0a7f964923e (MD5) / Made available in DSpace on 2016-02-23T23:10:23Z (GMT). No. of bitstreams: 1 MarcioAlvesDeMacedo_DISSERT.pdf: 2923226 bytes, checksum: e6a66719b01ddee0f70ac0a7f964923e (MD5) Previous issue date: 2015-02-26 / M?quinas de redu??o de grafos, s?o tradicionalmente utilizadas na implementa??o de linguagens de programa??o. Elas permitem executar programas (representados como grafos), atrav?s da aplica??o sucessiva de regras de redu??o. A composi??o de servi?os web permite a cria??o de novos servi?os web a partir de servi?os web j? existentes. BPEL ? a linguagem padr?o para criar composi??es de servi?os web como fluxos de trabalho. No entanto, o uso de BPEL para definir composi??es que usem outras tecnologias, al?m dos servi?os web n?o ? imediato. Na maioria dos casos, quando opera??es que n?o fazem parte do dom?nio dos servi?os web precisam ser executadas nas regras de neg?cio de uma empresa, parte do trabalho ? realizado de forma ad-hoc. Permitir que opera??es oriundas de diferentes tecnologias possam fazer parte de um mesmo fluxo de trabalho auxilia a cria??o de fluxos de trabalho mais adequados ?s necessidades das organiza??es. Esta disserta??o define uma variante da linguagem BPEL para a cria??o de composi??es com opera??es de servi?os web, tarefas de big data ou opera??es definidas pelo usu?rio. O suporte a esta linguagem ? dado mediante a defini??o de uma m?quina de redu??o de grafos extens?vel, a qual permite a execu??o de programas definidos na linguagem proposta. Esta m?quina ? implementada como prova de conceito. A proposta deste trabalho ? avaliada mediante a apresenta??o de resultados experimentais. / Graph Reduction Machines, are a traditional technique for implementing functional programming languages. They allow to run programs by transforming graphs by the successive application of reduction rules. Web service composition enables the creation of new web services from existing ones. BPEL is a workflow-based language for creating web service compositions. It is also the industrial and academic standard for this kind of languages. As it is designed to compose web services, the use of BPEL in a scenario where multiple technologies need to be used is problematic: when operations other than web services need to be performed to implement the business logic of a company, part of the work is done on an ad hoc basis. To allow heterogeneous operations to be part of the same workflow, may help to improve the implementation of business processes in a principled way. This work uses a simple variation of the BPEL language for creating compositions containing not only web service operations but also big data tasks or user-defined operations. We define an extensible graph reduction machine that allows the evaluation of BPEL programs and implement this machine as proof of concept. We present some experimental results.
5

Um ambiente para especifica??o e execu??o AD-HOC de processos de neg?cio baseados em servi?os Web

Mendes J?nior, Jos? Reginaldo de Sousa 29 August 2008 (has links)
Made available in DSpace on 2014-12-17T15:47:50Z (GMT). No. of bitstreams: 1 JoseRSMJ.pdf: 1414617 bytes, checksum: 1d2d0cfcaa6654701268463c98f3c2e9 (MD5) Previous issue date: 2008-08-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Recently the focus given to Web Services and Semantic Web technologies has provided the development of several research projects in different ways to addressing the Web services composition issue. Meanwhile, the challenge of creating an environment that provides the specification of an abstract business process and that it is automatically implemented by a composite service in a dynamic way is considered a currently open problem. WSDL and BPEL provided by industry support only manual service composition because they lack needed semantics so that Web services are discovered, selected and combined by software agents. Services ontology provided by Semantic Web enriches the syntactic descriptions of Web services to facilitate the automation of tasks, such as discovery and composition. This work presents an environment for specifying and ad-hoc executing Web services-based business processes, named WebFlowAH. The WebFlowAH employs common domain ontology to describe both Web services and business processes. It allows processes specification in terms of users goals or desires that are expressed based on the concepts of such common domain ontology. This approach allows processes to be specified in an abstract high level way, unburdening the user from the underline details needed to effectively run the process workflow / O enfoque dado ultimamente ?s tecnologias de Servi?os Web e da Web Sem?ntica tem proporcionado o desenvolvimento de v?rios projetos de pesquisa abordando, de diferentes maneiras, o tema da composi??o de servi?os Web. Entretanto, o desafio de criar um ambiente que favore?a a especifica??o de um processo de neg?cio abstrato e que seja implementado automaticamente por servi?os compostos de forma din?mica ? considerado atualmente um problema em aberto. Os padr?es WSDL e BPEL providos pela a ind?stria de software suportam apenas a composi??o manual de servi?os, pois falta a eles a sem?ntica necess?ria para que os servi?os Web sejam descobertos, selecionados e combinados por agentes de software. As ontologias de servi?o providas pela Web Sem?ntica enriquecem as descri??es sint?ticas dos servi?os Web de modo a facilitar a automa??o de tarefas, como a descoberta e a composi??o. Este trabalho prop?e um ambiente para a especifica??o e execu??o ad-hoc de processos de neg?cio baseados em servi?os Web chamado WebFlowAH. Este ambiente emprega uma ontologia de dom?nio comum para descrever tanto os servi?os Web e quanto os processos de neg?cio. Ele permite a especifica??o de processos em termos de desejos ou objetivos do usu?rio que s?o expressos por conceitos da ontologia de dom?nio comum. Tal abordagem permite que processos de neg?cio sejam especificados de maneira abstrata e de alto n?vel, liberando o usu?rio de detalhes necess?rios para executar eficazmente o workflow do processo
6

Cloud Integrator: uma plataforma para composi??o de servi?os em ambientes de computa??o em nuvem / Cloud Integrator: a platform for composition of services in cloud computing environments

Cavalcante, Everton Ranielly de Sousa 31 January 2013 (has links)
Made available in DSpace on 2014-12-17T15:48:05Z (GMT). No. of bitstreams: 1 EvertonRSC_DISSERT.pdf: 4653595 bytes, checksum: 83e897be68464555082a55505fd406ea (MD5) Previous issue date: 2013-01-31 / 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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