Web service composition validation via distributed compiler

This paper discusses a model for verifying service composition by building a distributed semi-compiler of service process. In this talk, we introduce a technique that solves the service composition problems such as infinite loops,deadlock and replicate use of the service. Specifically, the client needs to build a composite service by invoking other services but without knowing the exact design of these loosely coupled services. The proposed Distributed Global Service Compiler, by this article, results dynamically from the business process of each service. As a normal compiler cannot detect loops, we apply a graph theory algorithm, a Depth First Search, on the deduced result taken from business process files.

2005

Web Services are software platform-independent applications that export a description of their functionalities and make it available using standard network technologies. Such standards allow developers to access applications deployed over the network based on what they do, rather than on how they do it, or how they have been implemented. Thus, Web Services promise to give rise to new opportunities in developing and deploying distributed software applications.

Proceedings of the 6th international conference on Web engineering - ICWE '06, 2006

Web services provide a language-neutral, looselycoupled, and platform-independent way for linking applications within organizations or enterprises across the Internet. Web services communicate with each other via XML format messages. This paper presents a web service architecture model, Service-Oriented Software Architecture Model (SO-SAM), which is an extension of SAM (Software Architecture Model [15]) to the web service applications, as well as a validation of the model and a case study. SO-SAM is an executable architectural model incorporating the semantics of Predicate Transition Nets with the style and understandability of component-based concepts. SO-SAM describes each web service in terms of component and service composition in terms of connector separately. We believe that SO-SAM facilitates the verification and monitoring of web services integration since SO-SAM fits the distributed nature of modern composite web services. In order to validate the model against system properties, we translate the SO-SAM into the Maude programming language, a high level language and high performance executable specification with the componentized and objectoriented design. Finally, a case study of the validation of the model is demonstrated.

Lecture Notes in Computer Science, 2005

Most of the work on automated composition of web services has focused so far on the problem of composition at the functional level, i.e., composition of atomic services that can be executed in a single request-response step. In this paper, we address the problem of automated composition at the process level, i.e., a composition that takes into account that executing a web service requires interactions that may involve different sequential, conditional, and iterative steps. We define two kinds of process-level composition problems: on-the-fly compositions that satisfy one-shot user requests specified as composition goals, and a more general form, called once-for-all compositions, whose goal is to build a general composed web service that is able to interact directly with the users, receive requests from them, and propose suitable answers. We propose a solution to these two kinds of process-level compositions, and apply the solution to the case of web services described in OWL-S. As a result, we automatically generate process-level compositions as executable OWL-S process models. We show that, while executable on-the-fly compositions can be described as standard OWL-S process models, once-for-all compositions need OWL-S process models to be extended with receive and reply constructs.

Web services are utilized to illuminate some particular assignment. When a single web service cannot solve a given task, several web services are composed. Composition can be done either statically at design time or dynamically at runtime. Dynamic composition is more suitable for business applications where in business policies and user requirements frequently changes. Interleaved dynamic composition and execution of services is beneficial for adapting to changing user preferences. One of the main issues in such a scenario is that whether the component services that are composed operate according to the business rules specified. Safety, liveness and deadlock freedom properties of a composition depend on the behavior of individual services. Existing modeling techniques capture these properties and perform model checking only statically. Hence in this work, a two level model verification approach has been proposed to verify the correctness of dynamically composed services.

Proceedings of the 2010 Symposium on Information and Communication Technology - SoICT '10, 2010

Service composition is one of the primary tasks in developing service-oriented systems. However, there are currently some challenges to check its correction. In this paper, we propose a visual methodology and a tool for verifying business processes written in BPEL by using the SPIN model checker. We present algorithms to translate BPEL processes into PROMELA programs via labeled control flow graphs. The use of label control graphs in the tool will help regular users understand BPEL business processes and the verification process with a model checker more easily. Finally, the Spin model checker will verify important properties of the PROMELA program that represents a BPEL business process..

Resumen ENARM Urología

2004

PETER SCHANTZ är högskolelektor och leder den flervetenskapliga forskningsgruppen för rörelse, hälsa och miljö vid Åstrandlaboratoriet på Idrottshögskolan i Stockholm.

XVI Encontro Nacional de Pesquisadores em Serviço Social, 2018

Este artigo analisa a formação social brasileira, as expressões da “questão social” e reflete acerca das implicações para o exercício profissional do Serviço Social. A metodologia utilizada no ensaio teórico considerou a abordagem qualitativa, com caráter exploratório, utilizando transcrições de aulas e revisão de literatura. O objetivo geral é desvelar elementos que expliquem as consequências negativas da “questão social” na sociedade e os desafios ao Serviço Social brasileiro. Em tempos de estratégias neoconservadoras a agenda do projeto societal burguês tem ocasionado retrocessos no âmbito das políticas públicas e setoriais, agravando as expressões da “questão social”.

LIMA, N.F. , 2024

Fruto do colóquio "Textos Sagrados, Violência e Paz" (2023), do doutorado em Ciências da Religião da PUC Goiás, o texto se propõe a aprofundar o paradoxo de violência e paz na Sagrada Escritura, com ênfase nos "Profetas Maiores" (Isaías, Jeremias e Ezequiel). Propõe-se neste ensaio identificar os diferentes tipos de violência descritos na Bíblia para um melhor aclaramento da discussão e, em seguida, expor como os três grandes profetas a denunciam e propõem a paz individual e sistêmica como verdadeira vontade divina para o ser humano e a Criação. Considera, por fim, que a violência profética do período pós-exílico vai gradativa e conscientemente apelando para um novo processo de civilidade e direitos humanos, como alternativa ao terror de suas palavras naquele contexto sociopolítico e religioso.