Ontology Learning Techniques

As I planned, finalizing my (quick) studies on ontology learning techniques. Ontologies play a key role in semantic web and technologies by defining concepts and relations between these concepts. Thus, there are significant studies on this subject and some useful techniques discussed in ontology learning:

Almost all of the techniques above require a good knowledge and infrastructure of NLP (Natural Language Processing) to obtain effective results. I though ontology learning from dictionary would be easy compared to other methods for Turkish language. However, it requires WordNet like dictionaries that what I don’t have. Sabancı University NLP group works on BalkanNet but I don’t think it is ready to use.

Also, I’m searching about ontology-based system designs and implementations.