Rough semigroups and rough fuzzy semigroups based on fuzzy ideals
The authors of this article study some properties of rough subsemigroups and rough fuzzy subsemigroups of semigroups. They construct the \(t\)-level relation \(U(\mu, t)\) of a fuzzy ideal \(\mu\) of semigroups, and prove that \(U(\mu, t)\) is a congruence relation. The authors also consider the notions of lower and upper approximations based on a fuzzy ideal in semigroups, obtaining several interesting results.
scientific article; zbMATH DE number 6675362
scientific article