Utypes and SIAP evolution

[Francois Bonnarel]

Dear Dal and DM members
This mail is to be replied on DAL ONLY, to
avoid cross posting inflation.

      The two notes I edited in April:
"Data Model serialisation in VOTable (M.Louys, F.bonnarel)"
and
"Proposal for an evolution of the SIA protocol (T.Boch et al)"
are now available since Friday as "official" IVOA Notes
http://www.ivoa.net/Documents/Notes/DMVOTSer/DMVOTSer.html
and
http://www.ivoa.net/Documents/Notes/SIAPEvol/SIAPEvol.html
The example in the second of these notes has been upgraded since April with
a tentative ivoa:observation utype flagging.
This takes into accounts JMcDowell proposal : "Utypes for SIAP"
and the IVOA Observation data model working draft and diagrams,
which contain "draft" attributes.

In some cases we looked for alternative utypes from STC or Quantity
Data models. We do not see it as a drawback to have several utypes    
(actually a multipart single utype) for the same field in our VOTable.

In the context of this SIAP evolution proposal, where we describe 
Observations in a structured VOTable, what do we expect from the
utypes: 
     Provide an accurate IVOA/admitted definition for our fields.
And therefore allow any kind of software reading and interpreting this
VOTable to take appropriate decisions.

    In conclusion: the structure of our VOTable maps an "intermediate"
data model, ie between proprietary data model and IVOA data model (in our
example it is the IDHA one, but it could be any other of this type).
The utype gives the"official"  link(s) to the IVOA DM(s)


Regards
François

=====================================================================
Francois   Bonnarel               Observatoire Astronomique de Strasbourg
CDS (Centre de donnees          11, rue de l'Universite
astronomiques de Strasbourg)    F--67000 Strasbourg (France)

Tel: +33-(0)3 90 24 24 11       WWW: http://cdsweb.u-strasbg.fr/people/fb.html
Fax: +33-(0)3 90 24 24 25       E-mail: bonnarel at astro.u-strasbg.fr
---------------------------------------------------------------------