Keyphrases
- query language
- rdf data
- data model
- semantic web
- topic maps
- expressive power
- rule language
- linked data
- sparql queries
- semantically annotated
- complex objects
- object oriented
- relational algebra
- ontology languages
- ontology learning
- query evaluation
- legal information retrieval
- conjunctive queries
- transitive closure
- metadata
- knowledge base
- conceptual model
- database
- regular expressions
- recursive queries
- knowledge representation
- semantic web technologies
- query interface
- rdf graphs
- data sources
- owl ontologies
- knowledge organization
- semantic web data
- linked open data
- data model and query language
- data complexity
- xml data
- xml documents
- natural language
- artificial intelligence
- information retrieval
- neural network
- databases