***Sci-Board-3
Dear all,
I think it is time to remind you what the goal of the Sci-Board on a short
time-scale is:
we (eg: IVOA project and people) urgently need a stabilized version of the
UCD vocabulary.
Adds-on are possible in this phase, but in the short term (<1 month) the main job is to get a basic ?kernel? of ?stable? words that can be immediately used by data providers. The starting point is the list of words already available as an IVOA-WD.
If the present version of the list is too much ?table/catalogue?-like for somebody's tastes, I remind that at CDS (just to quote one of the data centers) about 150.000 columns wait for a ?stable? ucd-vocabulary in order to be treated (e.g.: to have an ucd assigned to them), their number growing at the rate of 1000 per month.
What I mean is: they are already there. This is why at the joint UCD-VOEvent session we decided to postpone the discussion on <UCDs and the VOEvent vocabulary> (to be precise, on the <hypothesis> schema only, because actual UCDs are usable in other Event contexts/schemas) : to gather a real working vocabulary on events and associated hypothesis.
The situation is not very simple : on one hand we have now a <standard> way (a <precise> way) to define <fuzzy>-enough UCDs, on the other hand we need to have within the IVOA community (DM, Theory, VOEvent, ..) the possibility to express the same concepts using the same words. And, why not, using the same syntax already used for the UCDs.
A way out is to be rigorous and <open> at the same time.
I remind you that in the actual version of UCDs we do have <objects>: in the sense that we do (we can) distinguish between the temperature of a star (its effective temperature) and that of a detector or instrument. We do distinguish between the name/identifier of an astronomical object and that of a telescope, instrument, or even a fov. In all these cases we use ucd-words describing <objects> as <qualifiers>.
While today an UCD like : src.galaxies.S0 would be meaningless, meta.id;src.galaxies.S0 would not. In the UCD context src.galaxies.S0 is only a secondary word, but in another context it could be used as primary.
We can (I would say: we have to) work in this direction.
I totally agree with Rick's final statement on ontologies: we need standards NOW, not in 30-40 man-years time!
Best regards
Andrea
Andrea Preite Martinez andrea-at-rm.iasf.cnr.it Istituto di Astrofisica Spaziale Tel.:+39.06.4993.4641 Area di Ricerca di Tor Vergata Fax.:+39.06.2066.0188 Via del Fosso del Cavaliere 100 Cell:+39.339.381735500133 Roma