Query Answering over Fact Bases for Fuzzy Interval Ontologies
نویسندگان
چکیده
Temporal ontologies contain events that are concepts and roles with references to temporal intervals. Therefore, a temporal ontology induces the interval ontology. We consider fuzzy interval ontologies written in a fuzzy Boolean extension of Allen’s interval logic. Syntactically, the extended logic ELA is the set of all Boolean combinations of propositional variables and sentences of Allen’s interval logic. Semantics of ELA is defined using fuzzy interpretations of propositional variables and atomic sentences of Allen’s logic. An interval ontology in ELA is a finite set ELA sentences (formulas). A fact is an estimate of a formula i.e. an expression of the form r ≤ φ ≤ s where φ is a ELA formula and 0 ≤ r ≤ s ≤ 1. A fact base for an interval ontology is a finite set of facts with formulas from the ontology. We present a method of finding answers to queries addressed to fact bases for fuzzy interval ontologies. The method uses analytical tableaux.
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