He is also a senior software developer at Aduna, a company that produces software for querying, searching and navigation of large information spaces, and is one of the lead designers of the Sesame RDF framework. He is also involved in the Data Access Working Group of the W3C. Jeen received his PhD at the Vrije Universiteit Amsterdam, on the topic of storage, querying and inferencing for Semantic Web Languages. His current research is on software components and languages for the Semantic Web, such as RDF, RDF Schema, OWL and SPARQL. Link: Jeen´s Homepage