子句型缺省理论的推理算法

Algorithms of Clausal Default Theory

1 引言 缺省理论自1980年Reiter提出之后,已成为非单调推理的热点.在缺省逻辑中,扩张的概念至为重要.Reiter对特殊的缺省理论--正规缺省理论做了许多研究,并得出了一些漂亮的结果[1].Etherington给出了生成任意有穷有序半正规缺省理论的扩张的程序[7].张明义提出缺省的一种子类--自相容缺省理论,给出了相容缺省理论和自相容缺省理论的特征,并给出了一般缺省理论的扩张及主要推理问题的算法[3].

On the basis of Reiter's default theory and Zhang Mingyi's auto-compatible default theory, we make research into the characteristic of clausal default theory .especially the closed auto-compatible default theory. Firstly ,the equivalent theorem of Logic Deduce and Consistence of closed formulas set is attained. Then we propose the theorem of monotonicity with the number of extension. The relationship of auto-compatible default theory and ordered default theory is proposed. Also some useful algorithms are presented.