Fuzzy division in fuzzy relational databases: an approach

نویسندگان

  • José Galindo
  • Juan Miguel Medina
  • M. Carmen Garrido
چکیده

An approach to calculate the relational division in fuzzy databases is presented, starting with the GEFRED model. The tuples of the division are obtained with a possibility degree that indicates the extent to which they comply with the relational division requisites. The results obtained are those expected a priori. Furthermore, in order to formalize this method of fuzzy relational division, two new operators are de5ned which may be useful in other operations: the quali5ed fuzzy intersection and the generalized fuzzy projection with group functions. Some examples are included in order to clarify the method proposed here and the de5ned operators. A comparison with other fuzzy division approaches that appear in the literature is included too. c © 2001 Elsevier Science B.V. All rights reserved.

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عنوان ژورنال:
  • Fuzzy Sets and Systems

دوره 121  شماره 

صفحات  -

تاریخ انتشار 2001