1. School of Sciences, Zhejiang Sci-Tech University, Hangzhou 310018, China
2. School of
Mathematics and Statistics, Qinghai Nationalities university, Xining 810000, China
Abstract In this paper, the extensions of uninorms are studied. In bounded lattices, the concepts of retract, $(r, s)$-sublattice, retraction, and $e$-operator are introduced, the extensions of uninorms via retractions and $e$-operator on bounded lattices are presented, respectively. Also, the most properties of original uninorms are preserved by the extensions. Furthermore, the relationships between conjugate of uninorms and the extensions of uninorms are discussed.
