Multivalued dependencies in extended possibility-based fuzzy relational databases

A notion of semantic equivalence of fuzzy data is introduced. It is based on fuzzy relational databases, where fuzziness of data appears in attribute values in forms of possibility attributions, as well as proximity relations in attribute domain elements, called extended possibility-based fuzzy relational databases. Following this notion, the authors focus on the issues of fuzzy multivalued dependencies (FMVDs). A set of sound inference rules are proposed, which are similar to W.W. Armstrong´s axioms for classical cases, for fuzzy multivalued dependencies