One approach to this problem (Hong et al (2001)) is to replace the t-norm min(a,b) with the t-norm Tw(a,b) = a, if b=1; b, if a=1; 0, otherwise. Since T(a,b) is a shape preserving
operation under multiplication, it resolves the problem. This approach is used in Koissi
and Shapiro (2005).