中文摘要：

环境自适应的组合服务系统是未来软件系统的一个发展方向，不同于普通组合服务系统之处在于这种系统对系统运行的网络环境进行监测，并根据监测结果对组合服务进行合适的调整以保证软件系统的服务质量．由于通常的类别匹配式环境感知策略不满足系统中服务QoS连续性的需求，本文经过分析环境自适应的组合服务系统的运行原理，提出一个基于动态QoS计算的环境变化识别方法，实现了从环境监测到输出变化事件的系统的环境感知功能，给出了环境监测及变化识别策略，设计了整体的变化识别算法以及其中具体的变化识别阈值计算算法，并通过实验结果表明了变化识别方法可以良好并高效地完成系统的环境感知需求．

英文摘要：

Environmental adaptive composite service system is a future direction of software system. The difference from the common composite service systems is that this system monitors its network environment, and appropriately adjusts the composite services ac- cording to the monitoring results to ensure the QoS of software system. As the common strategy of environment awareness is mainly category-matching type, it cannot fulfill the requirement of service QoS continuity. This paper analyzes the running principle of the environmental adaptive composite service system~ proposes an environmental change identification method based on dynamic QoS cal- culation which can accomplish system~ function of environment awareness. The strategies of environment monitoring and change i- dentification are presented, also the algorithms for the whole change identification procedure and the calculation process of change i- dentification thresholds. A test proves the change identification method in this paper can complete environment awareness for system well and efficiently.