JOURNAL OF INEQUALITIES AND APPLICATIONS, 2013 (SCI-Expanded)
In this study, by means of the T-partial order defined in Karacal and Kesicioglu (Kybernetika 47:300-314, 2011), an equivalence relation on the class of t-norms on ([0, 1],<=, 0, 1) is defined. Then, it is showed that the equivalence class of the weakest t-norm T-D on [0, 1] contains a t-norm which is different from T-D. Finally, defining the sets of some incomparable elements with any x is an element of (0, 1) according to <=(T), these sets are studied.