中文摘要：

针对云制造环境下，因忽略制造过程层次化特性导致组合服务路径存在服务质量瓶颈及整体服务质量计算偏差的问题，建立了新的问题模型并提出了求解算法。首先通过分析制造任务的层次化特性，构建了层次化的云制造服务组合模型。继而使用模拟退火算法求解该模型，为提高算法的效率利用子路径的服务质量约束设计了提前剪枝策略。仿真实验证明了模型的正确性和算法的有效性。

英文摘要：

To cope with the quality of service（QoS） bottleneck and evaluation deviation ot compos- ite services path in cloud manufacturing（CMfg） system due to ignoring the hierarchical characteristics of the manufacturing processes, a mathematical model and a solution algorithm were proposed and studied. Initially, the hierarchical manufacturing cloud services composition（H-MCSC） model was formula- ted based on the hierarchical manufacturing implementation processes. Then,a simulated annealing algorithm was developed based on the analysis and properties of the H-MCSC model. Within the algorithm, a pruning strategy based on sub-paths QoS constraints was designed to improve the efficiency of the algorithm. Simula- tion experimental results prove the validity of the model and algorithm.