中文摘要：

改模知识存在描述不规范的问题，并需要从大量改模数据中推理出改模知识。在分析改模知识的基础上，提出了一种基于本体的多层知识表达与推理模型。借鉴现有的本体构建方法，定义了本体的概念、属性、关系、实例；建立了基于单层的改模知识推理规则和多层之间的改模知识推理规则，并设计了相应的推理算法。通过一个基于“批锋”缺陷的改模问题验证了基于本体的改模知识多层知识模型及其规则的正确性与可行性。

英文摘要：

There were the description problems which were not standardized in the mould--repair knowledge. Knowledge reasoning was necessary to use knowledge effectively in making injection mould repair schemes. According to the analysis of injection mould repair knowledge, a multi--layer knowledge representation and reasoning model based on ontology for mould repair knowledge was put forward herein. The features of the mould--repair knowledge were analized, and the model of the knowledge expression was established. The concepts, attributes, relations, and instants of the ontol- ogy were defined with the ontology design methodology. The reasoning rules and algorithm for single layer and multi--layer ontology--based mould repair knowledge were designed. At last the example about the defect of ＂flashing＂ was representated and reasoned by the knowledge model to demostrate the validity and the feasibility.