A Type-2 Fuzzy Relational Database Model

Nguyen Hoa


This paper introduces a type-2 fuzzy relational database model (T-2FRDB) as an extension of type-1 fuzzy relational database models with a full set of basic fuzzy relational algebraic operations that can represent and query uncertain and imprecise information in real world applications. In this model, the membership degree of tuples in a fuzzy relation is represented by fuzzy numbers on [0,1], and fuzzy relational algebraic operations are defined by using the extension principle for computing minimum and maximum values of such fuzzy numbers. Some properties of the type-2 fuzzy relational algebraic operations in T-2FRDB are also formulated and proven as extensions of their counterpart in the type-1 fuzzy relational database models.

DOI: 10.32913/rd-ict.vol3.no14.352


Fuzzy set, fuzzy relation, type-2 fuzzy relational database, type-2 fuzzy relational algebraic operation.


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