Smeconceptsusedinknowledgebasemaintenace,suchassequence,newlaw,user'srejectionandreconstructionsofaknowledgebase,arefirstintroduced,andthenaframeworkforextendedlogicprogramming(ELP)isgiven,whereanextendedlogicprogramisequivalenttoaknowledgebase.AtransitionsystemcalledR-calculusforELPisprovided.Foragivenknowledgebaseandauser'srejection,theR-calculusforELPwilldeducebestrevisionsofthebase.ThesoundnessandthecompletenessoftheR-calculusforELPareproved,andtheR-calculusforELPisimplementedinProlog.Inaddition,theresearchiscomparedwithotherrelevantwork.
