Abstract: Based on the principles of Cloud Manufacturing(CM)and Cloud Service(CS), fundamental features of CS oriented to Numerical Control Machining(NMC)were summarized, and key problems of NC machining resources and capabilities for CS were analyzed. To deal with process-related problems in NMC, a three-tiered NMC platform which included service management, application integration and data base was designed with particular attention to application integration and knowledge management. Through service composition and service control, the NMC platform could coordinate the whole process from drawing to parts and support various CM application modes. As knowledge plays a crucial role throughout such a system, an ontology-based basic framework of NC machining knowledge base was constructed, which included concept Layer, domain Layer and rule Layer. The proposed framework was used to describe concepts, cases and reasoning rules respectively, thus NC machining service was represented effectively and intelligent behaviors of the related systems was supported.

Key words: cloud manufacturing, numerical controlled machining, cloud service platform, knowledge base, ontology

摘要： 根据云制造、云服务的原理总结了数控加工云服务的基本特征，分析了数控加工资源和能力的云服务化关键问题。为应对数控加工云服务中的工艺相关问题，设计了一个更加注重应用集成和知识管理的三层（服务管理层、应用集成层和基础数据层）云服务平台。通过服务组合和服务控制，该平台能协调从图纸到零件的整个过程，并支持多种应用方式。鉴于知识在这种服务系统的整体运行中的核心作用，基于本体技术构建了数控加工知识库的基本架构，包括概念层、领域层和规则层三个层次，分别描述概念、实例和推理规则，以有效表达数控加工服务并支持相关系统的智能行为。

关键词: 云制造, 数控加工, 云服务平台, 知识库