Preface of the Special Issue of the Sixth French-Speaking Conference on Ontologies

The key role played by ontologies to solve interoperability issues is nowadays well established. They convey the necessary semantics which helps understanding, sharing and integrating heterogeneous information. The current issue of the Journal on Data Semantics publishes extended versions of selected papers from the 6th edition of the FrenchSpeaking Conference on Ontologies (JFO) held from 13 to 14th October 2016 in Bordeaux, France. All the extended papers went through an additional peer review process. As a result, three out of five selected papers have been accepted for publication in this issue. The first paper Harnessing the power of unified metadata in an ontology repository: the case of AgroPortal, by Clement Jonquet, Anne Toulet, Biswanath Dutta and Vincent Emonet, addresses the issue of describing knowledge resources included in ontology repositories and portals using metadata. The study reviews 23 existing standards and vocabularies to describe metadata for ontologies and suggests a simplified model of 127 properties for the description of ontologies. They have been implemented in the context of the ontology repository AgroPortal that is based on the NCBO technology.