What concerns me about these new XML coding ideas is how - and whether - they'll be used in practice. I think there is a real danger of putting people off following a recommended DC-in-XML serialisation. So they'll just continue to use the old 'fuzzy' form with their own additions.
I'm currently thinking about an XML serialisation of an application profile for a community that I suspect knows little about XML or about DC (at the abstract model level). I was debating with myself whether I could include, and explain the reason for:
<dc:title>
<dcx:ValueString>My Document</dcx:ValueString>
</dc:title>
rather than:
<dc:title>My Document</dc:title>
I suspect not. So I think
<dcx:statement dcx:propertyURI="http://purl.org/dc/elements/1.1/title">My Document</dcx:statement>
is probably a non-starter, though at least it doesn't go to a second level. I would have thought that people who wanted that sort of precision in modelling would use RDF anyway.
A problem with the first construct above - as well as having to explain what the 'ValueString' part is for - is that it goes down a level in the XML document, making life harder for a consuming application.
Is there an option of including an abbreviated form, with the 'valuestring' level implicit, for simple cases? Ie. <dc:title>My Document</dc:title> is shorthand for and implies <dc:title><dcx:ValueString>My Document</dcx:ValueString></dc:title>
I guess the serialisation I'm working on will have to be based on the old schemas anyway, because the new schemas are not yet decided.
Ann
-------------------------------------------------
Ann Apps. IT Specialist (Research & Development), MIMAS,
The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
Tel: +44 (0) 161 275 6039 Fax: +44 (0) 161 275 6040
Email: [log in to unmask] WWW: http://epub.mimas.ac.uk/ann.html
--------------------------------------------------
> -----Original Message-----
> From: DCMI Architecture Group [mailto:[log in to unmask]]
> On Behalf Of Andy Powell
> Sent: Friday, September 08, 2006 8:47 AM
> To: [log in to unmask]
> Subject: Re: [DC-ARCHITECTURE] Schemas and validation
>
> I'm worried that my phrase "change our ways and move to using..." below
> might have unnecessarily raised some alarm bells for people -
> particularly as to whether DCMI is likely to depricate in any sense the
> current way in which simple DC metadata is encoded in the OAI-PMH.
>
> In short, no, I don't expect the current mechanism for encoding simple
> DC in OAI-PMH is going to change. The oai_dc format will remain a
> useful way of encoding simple DC in XML.
>
> Any XML encoding of DC metadata is essentially a two-way mapping between
> constructs in the DCMI Abstract Model and constructs in the particular
> XML format. In the past, I guess I have been hopeful that there would
> be only one such mapping - but I now think that is unlikely to be the
> case. So whilst it may well be the case that DCMI will recommend one
> mapping, I think we will have to acknowledge that communities of
> practice may choose to use a different mapping to suit there particular
> needs and preferences. The important thing is that the mapping between
> the XML format and the DCMI Abstract Model is clear and unambiguous in
> each case.
>
> So it may be that the DCMI recommended way of encoding DC in XML moves
> away from how it is currently done in the OAI-PMH. But DCMI will
> continue to recognise the OAI-PMH way of doing things as a perfectly
> valid (though slightly fuzzy) mapping of a subset of the DCAM to XML -
> and one that has proved to be very useful for the OAI-PMH community.
>
> Andy
> --
> Head of Development, Eduserv Foundation
> http://www.eduserv.org.uk/foundation/
> [log in to unmask]
> +44 (0)1225 474319
>
> > -----Original Message-----
> > From: DCMI Architecture Group
> > [mailto:[log in to unmask]] On Behalf Of Andy Powell
> > Sent: 07 September 2006 17:38
> > To: [log in to unmask]
> > Subject: FW: Schemas and validation
> >
> > The message below was written by Pete as part of an off-list
> > discussion about the level of support that might be required
> > from DCMI in order to maintain XML Schemas associated with
> > the DC-XML recommendation. Issues like "do the schemas have
> > to be updated every time a new term is created?", "what is
> > the relationship between DCMI-maintained XML schemas and
> > application profile XML schemas?", etc.
> >
> > I thought that Pete's answer would be of interest here.
> >
> > Of course, in essence the answer is 'it depends'. But one of
> > the major things it depends on is whether we choose to move
> > forward with XML encoding guidelines that are broadly similar
> > to what we have done in the past, i.e. where we instantiate
> > properties using XML elements as in
> >
> > <dc:title> ... </dc:title>
> >
> > or whether we change our ways and move to using a construct like
> >
> > <dcx:statement
> > dcx:propertyURI="http://purl.org/dc/elements/1.1/title"> ...
> > </dcx:statement>
> >
> > The first form was proposed in the DC-XML document that went
> > out for public comment:
> >
> > http://dublincore.org/documents/2006/05/29/dc-xml/
> >
> > The second form in a subsequent revised proposal from Pete:
> >
> > http://dublincore.org/architecturewiki/DCXMLRevision/DCXMLGuid
> > elines/200
> > 6-07-04
> >
> > (reference [6] below).
> >
> > As far as I recall, there has been relatively little
> > discussion about these alternatives, yet this feels like it
> > should be a pretty contentious issue!??
> >
> > I tend to lean towards the second form on the grounds that it
> > reflects the abstract model more cleanly, it treats URIs in a
> > more uniform way and it leaves us with much simpler XML schemas.
> >
> > Some of the arguments around this are presented in Pete's
> > longer message below.
> >
> > But I'd be interested in others' views...
> >
> > Andy
> > --
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