Keyphrases
- ontology languages
- semantic web
- description logics
- data complexity
- formal semantics
- conceptual modeling
- data types
- query answering
- owl dl
- modular ontologies
- owl ontologies
- conceptual models
- information integration
- expressive power
- answering queries
- semantic annotation
- query evaluation
- knowledge acquisition
- query language
- np complete
- expert systems
- database