Keyphrases
- conceptual graphs
- semantic representation
- natural language
- knowledge structures
- domain ontology
- formal representation
- conceptual structures
- partial order
- enron email
- text mining
- spam filtering
- artificial intelligence
- natural language queries
- retrieval engine
- instant messaging
- high level
- semantic web
- general purpose
- natural language processing
- email messages
- databases
- ontology reasoning