开放逻辑中基于一优先序的R-重构

R\|RECONSTRUCTIONS BASED ON A PRIORITY RELATION

在开放逻辑中，Ｒ－重构作为一知识库或信念集修正的结果并不唯一，有时甚至太多而难于明确计算和表示．为此，文中给出了基于一优先序的Ｒ－重构的概念．基于一优先序的Ｒ－重构往往要比Ｒ－重构少得多，不存在上述Ｒ－重构的问题，在用户给出的关于一知识库中知识的优先序时，基于该优先序的Ｒ－重构可以用来刻画对该知识库的合理维护．文中从开放逻辑中的模型论概念——事实反驳出发，给出了基于优先序的重构的定义，刻画了这类重构的一系列重要性质，如可靠性，存在性，相对于优先序关系的单调性，以及连续性等．

In open logic the notion of R\|reconstruction plays an essential role. However, R\|reconstructions can be too numerous to compute and to list out. Based on a priority relation a new notion of R\|reconstruction is proposed, which does not have the problem mentioned above. Moreover, the notion is reasonable in characterizing the update of a knowledge base when some priority relation among the pieces of the knowledge base is given. Starting by the model\|theoretic notion of rejection by fact in open logic, the definition of R\|reconstruction is given based on priority relation. Then proved are a series of important properties about this kind of R\|reconstructions, including soundness, existence, monotonicity, and continuity.