Construction d'une ontologie de descripteurs UCD en astronomie

The Unified Content Descriptors (UCD) provides a formal vocabulary for astronom- ical data. A syntaxic standardisation of UCD has been set in order to control the vocabulary used for the description of astronomical measures, but no formal semantics has been defined for these descriptors. In this paper, we present a methodology for building an OWL ontology about these normalized UCD. This ontology is then exploited to retrieve the UCDs representing on the best way a description of an astronomical object given by a set of properties. An approximate 2-step classification is performed exploiting metadata describing links between lexical items used in the descriptions and objects properties used to define the UCD in the ontology. MOTS-CLES : Construction d'ontologie, classification approchee, classification progressive, OWL, logiques de descriptions, UCD