规则集的化简及相关性质的判定

Simplifing Set of Rules and Judging Relative Properties

摘要: 任给一个规则集，确定其等价的最简规则集，此理论问题的解决对实际构建专家系统的核心组成部分规则库有重要意义。本文运用逻辑代数的基本理论和方法，将给定规则集对应于一个逻辑函数，化简得到最简逻辑函数，其对应所求的最简规则集，其中每条规则具有独立性。通过查找化简过程保留的所有质蕴含中的特定项，还能直接判断规则集的完备性和矛盾性。这种方法无需利用规则进行推理，可以统一运用于检测规则库的其它多种问题。

Abstract: Determining an equivalent minimal form for a given set of rules is important to build a rule base that consists of the key part of an expert system. Using logic algebra for solving the problem, this paper first transforms the given set of rules into a logic function, then simplifies the logic function by the means of logic algebra and finally convert the result function into a desired simplest set of rules in which each rule is independent. Through looking up special items in all prime implicates obtained in the above procedure, the completeness and contradictoriness of a set of rules can be judged out directly. This method can also be used to detect other problems in rule base without rule-based reasoning.