Tony Gill wrote:
>
> On a related topic, I had some discussions with the Getty Information
> Institute (publishers of the Art & Architecture Thesaurus, the Union
> List of Artists Names and soon the Thesaurus of Geographic Names)
> recently, and they expressed an interest in producing an authoritative
> registry of their scheme names, descriptions, versions etc. for use with
> DC metadata.
>
> I hadn't previously considered the need to enter the 'namespace' of the
> authorities' facets themselves though... would these also need to be
> registered?
Earlier today, Charles wrote a(nother) mail explaining namespaces. It
hasn't yet appeared in the meta2 archive and I haven't received my copy --
maybe the Internet is clogged up just now or maybe it's got lost somewhere.
In case it does appear, I won't rehash his mail, but one of the things he
explains is that XML namespaces are used *instead* of registration.
The question boils down to: Are all terms within all the AAT Thesauri
unique and guaranteed to stay unique? If yes, we can ignore the facets
and write something like:
<?XML:namespace href="http://dublincore.org/elements" as="DC"?>
<?XML:namespace href="http://getty.org/aat" as="Getty"?>
<?XML:namespace href="http://ddc.org" as="Dewey"?>
<DC:Creator>
<DC:Name>Albert Einstein</DC:Name>
<DC:Role>
<Getty:AAT>Scientist</Getty:AAT>
</DC:Role>
</DC:Creator>
<DC:Subject>
<Getty:AAT>Physics</Getty:AAT>
<Dewey:DDC>1234</Dewey:DDC>
</DC:Subject>
If the terms are not guaranted to be unique, then we need to qualify them
using the facets (on the asumption that they are unique within a facet).
This might be done as follows:
<?XML:namespace href="http://dublincore.org/elements" as="DC"?>
<?XML:namespace href="http://getty.org/aat" as="AAT"?>
<?XML:namespace href="http://ddc.org" as="Dewey"?>
<DC:Creator>
<DC:Name>Albert Einstein</DC:Name>
<DC:Role>
<AAT:HG>Scientist</AAT:HG>
</DC:Role>
</DC:Creator>
<DC:Subject>
<AAT:KD>Physics</AAT:KD>
<Dewey:DDC>1234</Dewey:DDC>
</DC:Subject>
Some notes on the above:
1. David Bearman explained that:
> HG (People and Organizations, wherein are all roles)
> FL (Styles and Periods, wherein are all nationalities, a well as periods)
> KD (disciplines)
> ...
2. The reason I've put <Getty:AAT> rather than just <AAT> is that the
XML namespaces spec requires a name on each side of the colon.
Ditto for <Dewey:DDC>.
3. This is my view of how Schemes should be handled. There are other
approaches which treat the name of the Authority as pure data and so
do not allow the use of XML namespaces and provide no mechanism for
generating unique names.
---------------------------------------------------------------------------
Misha Wolf Email: [log in to unmask] 85 Fleet Street
Standards Manager Voice: +44 171 542 6722 London EC4P 4AJ
Reuters Limited Fax : +44 171 542 8314 UK
---------------------------------------------------------------------------
12th International Unicode Conference, 8-9 Apr 1998, Tokyo, www.unicode.org
7th World Wide Web Conference, 14-18 Apr 1998, Brisbane, www7.conf.au
---------------------------------------------------------------------------
------------------------------------------------------------------------
Any views expressed in this message are those of the individual sender,
except where the sender specifically states them to be the views of
Reuters Ltd.
