new characterization schema: STC Concerns and Proposal

[Arnold Rots]

The question about encapsulating elements really is: at what level?
ObsDataLocation obviously can be regarded as a public class, but some
of the low-level elements are really private classes since they lose
some of their functionality when taken out of context.
I guess I was suggesting to let ObsDataLocation be the XML schema
implementation of Characterisation, in which case the indirection is
not required anymore.
But see what you can work out.

  - Arnold

louys at alinda.u-strasbg.fr wrote:
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> 
> 
> Dear Arnold,
> 
> My first impression is that your suggestion would impose an overhead in 
> the characterisation strucure , because each characterisation item , at 
> the 1-2 levels will have to point to the ObservationLocation structure 
> which means one added level of indirection.
> I would really prefer to use the STC structures in an object oriented 
> way , that is encapsulating STC elements.
> 
> we 'll work out examples on instance documents, to check for the 
> feasibility of your approach in our context.
> 
> cheers, Mireille
> 
> Quoting Arnold Rots <arots at head.cfa.harvard.edu>:
> 
> > 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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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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