Metadata for the VO: The Case of UCDs
Abstract
The UCDs (Unified Content Descriptors) were first developed in the ESO/CDS data mining project, to describe precisely the contents of the individual fields (columns) of tables available from a data center. They have been used to describe the content of the 105 columns available in the different VizieR tables.
Owing to the wide diversity and high heterogeneity of table contents, UCDs constitute an excellent starting point for a hierarchical description of astronomy, for general data mining purposes. We present different applications of UCDs: selection of catalogues, based on their content; identification of catalogues having similar fields; automated data conversion allowing direct comparison of data in cross-identifications. The compatibility of UCDs with semantic descriptions developed in other contexts (data models for space-time coordinates or image datasets) will also be addressed.- Publication:
-
Astronomical Data Analysis Software and Systems XII
- Pub Date:
- 2003
- Bibcode:
- 2003ASPC..295...69D