The maintenance sequences of a knowledge base and their limits are intro-duced. Some concepts used in knowledge base maintenance, such as new laws,user's rejections, and reconstructions of a knowledge base are def...The maintenance sequences of a knowledge base and their limits are intro-duced. Some concepts used in knowledge base maintenance, such as new laws,user's rejections, and reconstructions of a knowledge base are defined; the re-lated theorems are proved. A procedure is defined using transition systems; itgenerates maintenance sequences for a given user's model and a knowledge base.It is proved that all sequences produced by the procedure are convergent, andtheir limit is the set of true sentences of the model. Some computational aspectsof reconstructions are studied. An Rcalculus is given to deduce a reconstruc-tion when a knowledge base meets a user's rejection. The work is comparedwith AGM's theory of belief revision.展开更多
文摘The maintenance sequences of a knowledge base and their limits are intro-duced. Some concepts used in knowledge base maintenance, such as new laws,user's rejections, and reconstructions of a knowledge base are defined; the re-lated theorems are proved. A procedure is defined using transition systems; itgenerates maintenance sequences for a given user's model and a knowledge base.It is proved that all sequences produced by the procedure are convergent, andtheir limit is the set of true sentences of the model. Some computational aspectsof reconstructions are studied. An Rcalculus is given to deduce a reconstruc-tion when a knowledge base meets a user's rejection. The work is comparedwith AGM's theory of belief revision.
