Re: new characterization schema: STC Concerns and Proposal

When I asked yesterday why Characterisation wasn't using higher-level structures from STC, I was actually serious and even more so after Anita's presentation and some of the concerns that Igor voiced. I realized that the Characterisation schema is going through the same issues now, that I went through in the development of the STC schema, in terms of required axes, elements, and references. It seems unnecessary to have to rehash all of that again. In particular, by rebuilding the STC-related elements from lower level STC components the integrity of the coordinate metadata in the related axes is lost and it will be a major effort to regain it. The thing is that all of the axis-related stuff in Characterisation is contained in the ObsDataLocation element in STC, with the exception of sensitivity. It would be a rather simple thing to add the sensitivity concept to stc:AstroCoordArea. When that is done you would have a complete implementation of the axis-related characterisation in stc:ObsDataLocation, complete with all the proper structure and added value in a fully implemented referencing mechanism. It is easy to see that Anita's example would be completely represented in this - I'll provide an example of it next week.

I am not proposing any change in the Characterisation _model_, only in the XML schema implementation by simply plugging in ObsDataLocation which is a ready, complete, and tested element. Note that this same ObsDataLocation element is also used in the VOEvent schema.

I know that the organization of the information is different - the matrix is transposed, so to speak. But that was done to facilitate an easier implementation of the related coordinates. And it is only a matter of code: it should not be harder to present the information in a transposed view.

And I don't think it would delay the process, either. As I said, the model (and hence the WD) is not affected, while the schema development will be easier since all coordinate concerns are taken care of. I promise to add the sensitivity components right away to STC since it does not seem like that will be difficult since I should be able to take it from the current Characterisation schema.

Cheers,

• Arnold

Francois Bonnarel wrote:
[ Charset ISO-8859-1 unsupported, converting... ]
>
> Hi all,
> Version 0.95 of the characterization xml schema (axis first) is available
> following this link :
> http://Model/Characterisation/schema/characterisation.0.95.xsd
> It has been properly validated, importing stc1.3 schema and using
> xmlspy. So it could be possible to use it to develop validated examples.
>
> Best regards
> Fran?ois
>
> =====================================================================
> 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
> ---------------------------------------------------------------------
>

Arnold H. Rots                                Chandra X-ray Science Center
Smithsonian Astrophysical Observatory                tel:  +1 617 496 7701
60 Garden Street, MS 67                              fax:  +1 617 495 7356
Cambridge, MA 02138                             arots-at-head.cfa.harvard.edu
USA                                     http://hea-www.harvard.edu/~arots/
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