Good timing. I'm working on a registry driven by SKOS  that will feature resolvable URIs for values (or Concept labels, as I call them) commonly found in existing LC schemas, such as PREMIS, MODS and MARCXML. MARC too, of course. One of the goals is to then allow new values to be placed into the registry for possible inclusion into any relevant schemas. In theory these schemas could be then dynamically generated at request time with the relevant values that exist in the registry, but that has yet to be decided by those here in the NetDev office or the various boards that guide our schemas. It will be possible to register values in the registry but not have the affect the XML Schema outputs, though.
The registry will also have numerous other outputs for each value, including MADS, many flavors of RDF, etc. I'll likely have some query endpoints up for it too, for SPARQLs and XQueries.
You're right, that then in a MODS instance, you'll need a convention to get at the values in the registry. The values will either be built into the schema, or you'll have to use something like @xlink:href to process the URI, and an XInclude/XPointer/XQuery or the like to generate the proper text node for your <genre>. Also, in theory, the @authority values could use the URI for the SKOS ConceptScheme that contains the Concept label of interest.
e.g. (these won't resolve for another couple of weeks):
<genre authority="http://www.loc.gov/standards/registry/vocabulary/graphicMaterials" xlink:href="http://www.loc.gov/standards/registry/vocabulary/graphicMaterials/tgm000008" xlink:title="A la poupeč prints"><!-- Your XML tools should generate "A la poupeč prints from TGMII id#tgm000006 --></genre>
>>> Laura Akerman <[log in to unmask]> 07/16/08 6:15 PM >>>
I'm looking at how to set up one or more local (and idiosyncratic)
vocabularies that could be high-level subject or "genre" (best element
that fits) vocabularies, to describe special groupings we would want
(some guessed at examples, "yellow-back collection" "pamphlets by
African American authors" "art history web resources"). These might be
for internal use or public (e.g. website naviation of collections).
We'd like to be able to identify which local vocabularies we're using in
our MODS and MARC records. In MARC, the specification says to use a
term from the MARC Code list in subfield 2; the only one available to us
is "local". The MODS guidelines for authority attribute for both
subject and genre suggest using the MARC Code lists but don't prescribe it.
We'd like to go beyond "local" so we can code more than one local
Am thinking about inventing a convention, something like , e.g.,
<mods:genre authority="local GEU projectvocab"> to assign our own
abbreviation or label for a local vocabulary.
Has anyone else felt the need to do something like this, or tried it...
do you think this strategy would work, see any problems with it, or have
suggestions for an alternative strategy?
Beyond my immediate need: would a change in either the conventions for
use of the MARC codes for genre or subject, or the data structure to
permit identifying institution and local vocabulary code, be a good thing?
Thanks in advance for advice,
Laura Akerman, Technology and Metadata Librarian
Robert W. Woodruff Library, Room 128
Atlanta, Ga. 30322
ph: (404) 727-6888 / email: [log in to unmask]