First Approach of Type-2 Fuzzy Sets via Fusion Operators.

In this work we introduce the concept of a fusion operator for type-2 fuzzy sets as a mapping that takes m functions from [0, 1] to [0, 1] and brings back a new function of the same type. We study in depth the properties of pointwise fusion operators and representable fusion operators. Finally, we study the union and intersection of type-2 fuzzy sets and we analyze when these functions are pointwise and representable fusion operators.