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Web服务组合是面向服务的计算模式下应用构造的主要方式,而现有的组合方法与实施框架缺乏有效的验证机制,从而产生大量无效的组合结果.针对这一问题,提出一种具有正确性分析与验证功能的Web服务自动组合系统框架.其核心是利用有色Petri网对基于OWL-S的服务组合系统进行形式化建模,通过对组合模型的模拟执行及对其动态性能的全面分析,预测组合服务的执行结果,从而提高组合的可靠性.另外,该框架采用智能Agent技术,可有效实现组合过程的自动化.“,”Web services composition is a promising way to build an application in service-oriented computing (SOC) environments. Current approaches for service composition may return back lots of invalid results due to lacking effective verification mechanism. To address this issue, an automatic composition framework for semantic Web services with correctness guarantees was proposed. The framework exploits Colored Petri Nets (CPNs) to formally model achieved composition and then to verify its correctness based on simulation and analysis of the constructed model. By means of the proposed validation approach, certain composition errors can be detected in advance and dynamic properties of a composite service can be predicted, thus preventing it from runtime failure. Moreover, software agents are developed together with OWL-S specification in the framework to effectively enable automation in the process of composing Web services.