Natural dualities for varieties of distributive lattices with a quantifier
Let be a lattice. In this paper, corresponding to a given congruence relation of , a congruence relation on is defined and it is proved that 1. is isomorphic to ; 2. and are in the same equational class; 3. if is representable in , then so is in .
In this note, we point out that Theorem 3.1 as well as Theorem 3.5 in G. D. Çaylı and F. Karaçal (Kybernetika 53 (2017), 394-417) contains a superfluous condition. We have also generalized them by using closure (interior, resp.) operators.
In the study, we introduce the definition of a locally internal uninorm on an arbitrary bounded lattice . We examine some properties of an idempotent and locally internal uninorm on an arbitrary bounded latice , and investigate relationship between these operators. Moreover, some illustrative examples are added to show the connection between idempotent and locally internal uninorm.