The meeting began with a brief check on progress towards our next outreach meeting. Invitations have been sent out, the agenda
is evolving and all but one speaker has confirmed attendance. At the time of writing, there is likely to be space for a few more guests.
The group then turned its attention to the new POWDER model that was discussed at the recent Athens face to face (see Jeremy Carroll's summary
and previous entries on this blog).
Some questions and answers:
Is attribution element mandatory? Group resolved yes.
Is maker element within attribution mandatory. Group resolved yes (which, as an aside, retains POWDER's dependence on the FOAF vocabulary)
Why is the attribution element outside the DRs now? Because it's the only way to make statements about triples without using either reification or named graphs, both of which are unsafe for various reasons.
So how can you have DRs with different attribution? By having multiple POWDER documents (and it's worth noting that one POWDER package may link to DRs in other POWDER documents).
What about the human-readable text and/or icon - they need to be associated with a DR, not the document. True!
Are descriptors RDF predicates and objects or XML attributes and values? Both. Literal values can be encoded either way, but where the object is a URI it must be encoded using the rdf:resource="..." attribute. It's probably better and less ambiguous to use RDF/XML notation for the descriptors. Actually, only the URISet is constrained - this must not include any element from any namespace other than POWDER. Development of the XML Schema for POWDER will be influential here.
The conversation then moved on to look at the problem of 'switchable DRs' or cascading DRs. One solution was proposed and found wanting. We're still looking at how to enable a resource to include a link to a DR that describes, perhaps overriding a description already in cache.
There was a brief discussion of the group's timeline: the expectation is of new draft documents being published very soon and the hope of reaching Last Call at Easter. Note - the WG includes several Greek members - so Easter may be according to the Orthodox calendar! We will need to seek a charter extension.
Finally, e-mails received
on the public list were acknowledged.