Generalizing possibility-distribution-fuzzy-relational-models
نویسنده
چکیده
A genemlized possibility-distribution-fuzzy-relationalmodel is proposed considering semantic ambiguity for membership attribute values and ambiguity contained in them. And then the extended relational algebra is shown. In order to eliminate the semantic ambiguity, a membership attribute is attached to each attribute. This clarifies the origin of membership attribute values. What a membership attribute value means depends on the property of the attribute. In order to eliminate ambiguity contained an membership attribute values, those values are expressed b y possibility distributions. This clarifies what effects an imprecise attribute value has on its membership attribute value. Therefore, there is no semantic ambiguity for the membership attribute values and no ambiguity in them in the extended relational model.
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