[Voevent-core] Fwd: standard vocabulary

[Tony Linde]

Thanks for the explanation, Roy.

> between them. At the moment we are just building the nodes, 
> i.e. the controlled vocabulary.
> We could in the future build more structure.

But isn't something like 'process.variation.burst;em.X-ray' structured? Can
you also have burst.em.process? What is the difference between
process.variation.burst and process.burst.variation if there is any? If
there is a difference then it seems that there is some sort of semantic
meaning being invoked. No? or is it just that 'process.variation.burst' is
the term that has meaning, not the order of combination, and you have to
know that meaning to do anything with it?

T.

> -----Original Message-----
> From: roy at cacr.caltech.edu [mailto:roy at cacr.caltech.edu] 
> Sent: 17 May 2006 19:13
> To: Tony Linde
> Cc: semantics at ivoa.net
> Subject: RE: [Voevent-core] Fwd: standard vocabulary
> 
> Thank you for making this point Tony. There is a distinction 
> between UCD semantics (content description) and UCD syntax 
> (combination of word
> hierarchies) that should be made explicit.
> 
> > I've always seen UCDs as like data types. They are applied 
> to columns 
> > and describe what type of data is in the column - so they are data 
> > types. Much the same as 'float', which I guess you could call 
> > number.float;32bit
> 
> Yes. That is the right way yo think of UCD.
> 
> >  In which case GRB is not really relevant as a UCD, nor is 
> > process.variation.burst;em.X-ray.
> 
> We are trying to be careful to talk of "controlled 
> vocabulary" and "UCD syntax". Your example is not a datatype 
> or a UCD. Rather it is a piece of controlled vocabulary 
> expressed in a UCD-like syntax.
> 
> > So unless UCDs are now going to be turned into the new 
> astro thesaurus 
> > or a type of astro ontology, it doesn't seem to make sense 
> to have a 
> > UCD for GRBs.
> 
> Thesaurus and Ontology imply a set of nodes and relations 
> between them. At the moment we are just building the nodes, 
> i.e. the controlled vocabulary.
> We could in the future build more structure.
> 
> Roy
>