根据模糊蕴涵算子θ(a,b)关于后件变量b的单调性,将文献中的400多个蕴涵算子分为三类,即后件单增(减)和后件非单调模糊蕴涵算子。进一步,给出了不同类型的蕴涵算子构造的模糊系统的数学表达式。结果表明:若后件单增蕴涵算子θ(a,b)满足θ(a,1)=φ(a)或后件单减蕴涵算子θ(a,b)满足θ(a,0)=φ(a)(其中φ(a)为关于a的函数,且当0〈a〈1时,0〈φ(a)〈1),则由其构造的模糊系统的输出函数可为插值函数或拟合函数;若将蕴涵算子θ(a,b)视为后件变量b的一元函数时,θ(a,b)的最大值是与a无关的任意常量,则由该蕴涵算子构造的模糊系统的输出函数为阶跃函数,故这类模糊系统在实际应用中无太大意义。
Firstly,concepts of monotone increasing(decreasing) fuzzy implication operators with respect to consequent variables are proposed,and monotonicity of more than 400 fuzzy implication operators θ(a,b) with respect to consequent variable b is verified.Furthermore,fuzzy systems constructed by different implication operators are discussed,and their mathematical expressions are given.The conclusions show that if a monotone increasing implication operator θ(a,b) satisfies θ(a,1)=φ(a) or a monotone decreasing implication operator satisfies θ(a,0)=φ(a),in which φ(a) is a function with respect to a that satisfies 0〈φ(a)〈1 for a∈(0,1),the output function of the corresponding fuzzy system is an interpolation function or a fitting function;if the maximum of θ(a,b) is a constant,the corresponding fuzzy system has step output,so the fuzzy system isn't practical.