DC Architecture WG
meeting
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Wednesday 13.30 - 15.30
Seminar Room: 5205 (2nd Floor) |
Agenda
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Review of the Abstract Model and moving
forward
http://www.ukoln.ac.uk/metadata/dcmi/abstract-model/ |
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RDF resource vs. literal issue
http://www.ukoln.ac.uk/metadata/dcmi/rdf-values/ |
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XML schema issues
http://www.ukoln.ac.uk/metadata/dcmi/xmls-issues/ |
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Identifiers for historical versions of
metadata terms
http://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind0410&L=dc-architecture&T=0&O=D&P=3366 |
Review of the year
…but not that sleepy!
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Abstract Model document moved forward
(slowly) |
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“Expressing Dublin Core in HTML/XHTML
meta and link elements” issued as a DCMI Recommendation |
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discussion paper about assigning URIs
for metadata terms |
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something like 200 messages posted to
the dc-architecture mailing list |
Abstract Model
Major changes
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changed 'URI' to 'URI reference' at
appropriate points throughout |
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added 'description set' to the
description model to separate out the conceptual grouping of related
descriptions (a 'description set') from its instantiation in a particular
syntax (a 'record') |
Major changes (2)
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introduction of 'property/value pair'
into the resource model to separate abstract notion of a property from the
specific usage of a property to describe a particular resource |
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modified the definition of
'sub-property' in the resource model |
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Major changes (3)
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added of a note about needing to
indicate how 'resource URIs' and 'value URIs' are handled in encoding syntax
specifications |
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explicit indication that 'resource
URIs' and 'value URIs' are not supported by the current XML encoding
guidelines |
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explicit indication that 'resource
URIs' are not supported by the XHTML encoding syntax |
Model summary
Remaining issues
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possible need for further clarification
of how URIs are handled by the AM – in short, dcterms:URI is almost never
used and certainly not to indicate a ‘value URI’ |
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it would be better if we modelled
‘syntax encoding scheme URI’ and ‘vocabulary encoding scheme URI’ as separate
entities in the model |
Remaining issues (2)
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the AM currently restricts the number
of ‘parent’ properties that a sub-property can have to a maximum of one -
this is an error and will be made unlimited. |
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does the model get the definitions of
‘simple DC’ and ‘qualified DC’ right? |
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should the model support ordered lists
of values? |
RDF resource vs. literal
issue
The problem
Possible solutions
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Status quo |
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Align behaviour of consuming systems |
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Align behaviour of consuming and
generating systems |
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Attempt to influence the behaviour of
the wider Semantic Web community |
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Replicate existing DC property
semantics in new properties |
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XML schema issues
Identifiers for
historical versions of metadata terms
Slide 17
DC Architecture WG report
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agenda: |
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Abstract Model |
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encoding DC element values in RDF |
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XML schema issues |
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identifiers for DCMI term descriptions |
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21 attendees |
Wot we did last year…
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moved Abstract Model forward slowly |
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issued XHTML encoding guidelines as a
Recommendation |
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developed issues papers on identifiers |
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about 200 postings to the
dc-architecture mailing list |
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Abstract Model
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discussion around the meanings of
‘simple DC’ and ‘qualified DC’ |
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no consensus |
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agreed to remove definitions of these
terms from the Abstract Model |
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discussed possibility of adding support
for ‘ordered lists of values’ to the abstract model – little support for this
in the room |
DC values in RDF
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problem: some confusion in RDF
implementer community currently |
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solution (short-term): work item to
develop a short clarification document for RDF implementers |
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solution (long-term): work item to
develop a view of possible ‘encoding’ changes to remove confusion and carry
out impact analysis |
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undertaken by small ‘task force’ |
XML schemas
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agreed to provide a persistent URI to
the latest version of our XML schemes |
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agreed to provide two ‘container’
elements for DC descriptions, probably called <dcxml:description> and
<dcxml:descriptionSet> |
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work item: revise DC in XML Guidelines
to include explicit mechanism for value URIs |
Namespace policy
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work item: minimal update to the
namespace policy to align some of the terminology with current usage |
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consider ways of documenting how we
assign URIs to DCMI term descriptions |