关键词: 变精度粗糙集, 分层递阶表达, 改模知识归纳, 知识获取, 模具

Abstract: Rule sets could be obtained by knowledge induction for injection mould repairs based on rough sets theory, but the rule sets were in large-scale and with poor usability. Aiming at these problems, a new method of knowledge hierarchical induction based on variable precision rough sets was proposed. Firstly, hierarchical representation model of injection mould repair knowledge was set up and decision table sets were generated by the process of specification, completion and hierarchy to feature value. Secondly, classification quality/error matrix was introduced into the process of knowledge induction. The core features sets satisfied classification quality requirements from different engineers were acquired by feature hierarchical reduction based on variable precision rough sets. Then, the rule sets were obtained according to rules hierarchical reduction and knowledge acquisition. Finally, a case study was provided to illustrate the feasibility and effectiveness of the proposed method.

Key words: variable precision rough sets, hierarchical representation, mould repair knowledge induction, knowledge acquisition, mould