On ordinal sums of t-norms and t-conorms on bounded posets

This paper continues and generalizes the line of research on ordinal sum of t-norms and t-conorms on bounded lattices. We introduce a new ordinal sum construction on bounded posets based on interior and closure operators. Our proposed method provides a simple tool to introduce new classes of t-norms and t-conorms. Several necessary and sufficient conditions are presented for ensuring whether our generalized ordinal sum on a bounded posets of arbitrary t-norms is, in fact, a t-norm. We show that in this general setting the existence of our ordinal sum for t-norms requires that the respective interior operators are t-norm preserving.