Title: Description Logics Description Logics
نویسندگان
چکیده
KR: knowledge representation. DLs: Description Logics; a family of logic-based KR languages for representing knowledge through assertions about concepts, individuals and relationships among them. (Logic-based) Semantics: a way to interpret any statement in a language; logic-based semantics interprets such a statement using operations in mathematical logic. Interpretation: a mathematical structure realizing the semantics of a language, typically consisting of an underlying set (domain of interest) and a mapping from the statements in the language to the set or mathematical operations on it. Model: an interpretation that interprets logical statements in non-contradictory way. Individual: an element of the domain of interest. Individual names are atomic statements in a DL corresponding to such elements. Concept: a statement in a DL corresponding to sets of individuals. Role: a statement in a DL corresponding to a binary relation between individuals. Axiom: a statement in a DL that asserts certain constraints that have to be satisfied by some concepts, roles and individuals. TBox: a set of axioms constraining concepts. ABox: a set of axioms constraining particular individuals. RBox: a set of axioms constraining roles. KB: knowledge base; a set of axioms of any kind. Reasoning: a process in which implicit knowledge/facts are inferred from explicit knowledge given through a set of axioms. Open-world Assumption: a meta-level semantical assumption in which a statement is considered false only when the KB forces it so. This means a lack of knowledge does not imply falsity.
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