带否定的DATALOG的语义的不动点特性

THE FIXPOINT CHARACTERISTIC OF SEMANTICS OF DATALOG WITH NEGATION

带否定子目标的ＤＡＴＡＬＯＧ（称为ＤＡＴＡＬＯＧ）是ＤＡＴＡＬＯＧ的一种扩充。本文研究ＤＡＴＡＬＯＧ语义的良基模型的不动点特性。首先，重新考察了稳定性变换，定义了新算子及其不动点。在此基础上，定义了振荡不动点模型论语义，然后，本文证明了振荡不动点模型和良基模型是等同的，说明前者可以看和是后者的构造性定义。

Datalog with negation(called Datalog￣ )is an extension of Datalog.The fixpoint characteristic of well -founded model semantics of Datalog￣ is discussed in this paper.At first,the stability transformation is revisited, and a new operator OP and its fixpoint are defined.Based on this,the oscillating fixpoint model semantics is defined.Then,it is shown that for any datalog￣ program the oscillating fixpoint model is identical to its well-founded model,and so,the former can be viewed as a constructive definition of the latter.