IVOA Thesaurus

[Frederic V. Hessman]

Alasdair Gray noted:

> First of all I would like to talk about top level concepts. I found  
> that there were 2,646 top level concepts. I feel this very high,  
> particularly as there are only about 2,850 concepts in total. This  
> is also particularly bothersome if you analyse the IAU Thesaurus  
> which only has 516 top level concepts.
Strange, my python script claims that there are 2972 tokens in the  
newest version (which now includes all the elements and so had to  
grow a little bit!) and only 968 top concepts.  The script simply  
looks for BT's and NT's, which we know are not yet internally  
consistent, so maybe this is a good time to clean up the ontological  
connections.  Alasdair undoubtably used some smarter tools than my  
python script and the RDF hasTopConcept list should be taken with a  
grain of salt...

Latest changes:

	- Alasdair's latest corrections have been implemented (mostly typos)

	- all elements, their official symbols as aliases plus their links  
to appropriate other tokens; "mercury_manganese_stars" makes more  
sense when you know there is something called "element_mercury" (as  
opposed to the token "Mercury") and "manganese".

	- a few solar terms needed by the solar VOEvent community

The new documentation is a bit easier to use - just one top-level  
page at

		http://www.astro.physik.uni-goettingen.de/~hessman/rdf/IVOAT/

with links to the introduction, dictionary, and lists of tokens,  
labels, and aliases.   The alphabetic link buttons at the bottom  
aren't perfect but should enable you to browse more conveniently (the  
direct links between the list items and the dictionary are now broken  
- next thing to be fixed).



A more formal question:  I've been shoving UF's into aliases (a  
process which has not been completed, since I'm mostly doing this  
myself on spare time), but SKOS doesn't seem to have a means of  
expressing U's?

Rick