Fuzzy modus tollens ( FMT ) is one of the most basic inference forms in fuzzy reasoning. As a premise of FMT, fuzzy negation plays a major role in inference. In this paper, based on the fuzzy propositional logic with contradictory negation, opposite negation and medium negation ( FLCOM ) , contradictory negation, opposite negation and medium negation are proved to be different fuzzy negations, and thus three kinds of fuzzy modus tollens, FMT1 , FMT2 and FMT3 , are proposed,which are different from FMT respectively based on contradictory negation, opposite negation and medium negation. Furthermore, based on the R-implication operator IR, a fuzzy NR-implication operator INR is defined which is associated with IR. The algorithms of FMT1, FMT2 and FMT3 are proposed according to the algorithm of FMT, and it is proved that algorithms of FMT1, FMT2 and FMT3 are reducible algorithms when I ≤INR.%模糊拒取式推理( FMT)是模糊推理中最基本的推理形式之一,FMT的一个前提———模糊否定在推理中较重要.文中基于区分矛盾否定、对立否定和中介否定的模糊命题逻辑形式系统(FLCOM),证明矛盾否定、对立否定和中介否定是3种不同的模糊否定,提出与FMT不同的,分别基于矛盾否定、对立否定和中介否定的3种模糊拒取式推理FMT1、FMT2和FMT3.此外,基于R-蕴涵算子IR 定义一种与IR 关联的NR-蕴涵算子INR,并依据FMT的算法给出FMT1、FMT2和FMT3的算法,证明FMT1、FMT2和FMT3的算法在I ≤INR条件下是还原算法.
展开▼
