Small is Again Beautiful in Description Logics Franz Baader TU Dresden, Germany
Semantic networks Animal Frog Green Kermit Leaf Tree [Quillian, 1967] one of the origins of DLs Semantic networks [Quillian, 1967] Animal IS-A has-color Frog Green IS-A IS-A has-color has-part Kermit Leaf Tree sits-on
Problems with Semantic Networks
Ambiguities in Semantic Networks Animal IS-A color Frog Green
Ambiguities resolved in DLs Animal IS-A color Frog Green
Description logic system structure
Complexity of reasoning tractability barrier
Ways out of this dilemma expressive DL sound, but incomplete tractable algorithms expressive DL sound and complete intractable algorithms inexpressive DL sound and complete tractable algorithms approach followed by main-stream DL research in the last 15 years
Ways out of this dilemma expressive DL sound, but incomplete tractable algorithms expressive DL sound and complete intractable algorithms inexpressive DL sound and complete tractable algorithms
Description Logics research of the last 20 years
Light-weight DLs subsumption and classification tractable sufficient expressive power for life-science ontologies
Value restrictions vs existential restrictions in DLs
Formal semantics
Subsumption
Complexity of subsumption
Extension
Extension
Extension
CEL
Light-weight DLs query answering using relational database systems sufficient expressive power to capture conceptual modelling formalisms
Conjunctive query
Query answering
Query answering
Query answering
Questions?