中文摘要：

为了保证web服务事务获得正确的执行和一致的结果，对Web服务事务处理的形式化研究是很重要的．现有研究集中在事务的建模和协议验证上，对事务特性仍缺乏深入研究．已有的事务建模方法主要采用增加额外的操作算子来描述事务补偿语义，而过于复杂的语法和迁移规则不利于对事务特性的进一步分析．在不增加新的操作算子的前提下，引入事务膜的位置概念来表示事务作用域，将进程的交互动作与消息相对事务膜的传递过程相关联，对π-演算进行扩充．结合进程行为的事务依赖性，提出了一种弱事务性开互模拟，来刻画可见事务行为的等价关系，利用互模拟等价理论分析了弱事务性等价关系的基本性质，为研究Web服务的事务特性提供了理论基础．

英文摘要：

As Web service transactions have been firmly established and widely adopted, it is important to adopt a suitable formal method to specify transaction processing in Web services. However, current research has focused on the modeling for transaction and validating of standards, the study of Web service transactional properties is still lacking. There exists a formal method of transaction processing which appends some operators and makes the syntax and reduction rules so complex that it is hard to analyze further the transactional properties. Aimed at this problem, without introducing any action operator, an extended n-calculus is proposed based on the connection between the process interactives and the transmission process of message relative to the transaction scope. And the membrane activities are defined. This biological membrane structure naturally characterizes the exception handling and compensation transactions in the multi scopes for Web services. The syntax, structural congruence and reduction rules of the extended n-calculus are given successively. According to the transactional dependency, a new weak transactional open bisimulation relationship is also presented to characterize the equivalent relationship in visible transactional action. Based on the bisimulation, its equivalency analysis is explored. All of the results can help to lay a substantial foundation for a further analysis of transactional properties for Web services.