JACIII Vol.3 No.1 pp. 3-12
doi: 10.20965/jaciii.1999.p0003


A Semantic-Ambiguity-Free Relational Model for Handling Imperfect Information1

Michinori Nakata

Department of Information Science, Chiba-Keizai College
4-3-30 Todoroki-cho, Inage-ku, Chiba 263-0021, Japan

June 22, 1998
September 18, 1998
February 20, 1999
Semantic ambiguity, Membership attributes, Fuzzy databases, Extended relational algebra, Extended relational models.
An extended relational model without semantic ambiguity, called a semantic-ambiguity-free relational model, is proposed using fuzzy sets and the theory of possibility. The model features every attribute having a membership attribute whose value consists of a pair of values based on necessity and possibility measures. The membership attribute value of an attribute in a base relation is the degree to which the attribute value is compatible with integrity constraints imposed on the base relation. This clarifies the source of the membership attribute value. The model has no semantic ambiguity for interpreting membership attribute values, unlike models consisting of relations with membership attribute values attached to tuple values. We show the formulation of 8 operations - union, intersection, difference, Cartesian product, projection, join, selection, and quotient - consisting of relational algebra proposed by Codd for query processing. This approach shows how to prevent users from misinterpreting tuples in databases allowing imperfect information.
Cite this article as:
M. Nakata, “A Semantic-Ambiguity-Free Relational Model for Handling Imperfect Information1,” J. Adv. Comput. Intell. Intell. Inform., Vol.3 No.1, pp. 3-12, 1999.
Data files:

*This site is desgined based on HTML5 and CSS3 for modern browsers, e.g. Chrome, Firefox, Safari, Edge, Opera.

Last updated on Jul. 19, 2024