Douglas said:
> 1. "A description is made up of... zero or one resource URI"
> - I would think it would be valid for a single resource to
> have multiple identifiers, especially for physical resources?
>
> 2. "A statement... is made up of... zero or one value URI" -
> Similiarly for values there could be multiple URIs,
> especially since the model states a value may be a member of
> more than one vocabulary (and so is very likely to have
> multiple URIs)?
The DCAM does not rule out a single resource being identified by
multiple URIs.
The description model allows a maximum of one "described resource URI"
in a description (to refer to the "described resource") and a maximum of
one "value URI" in a statement (to refer to a "value").
So the description model itself does not say anything about how to
specify that two URIs identify the same resource: it leaves it up to the
metadata creator to construct statements using a suitable property e.g.
the OWL sameAs property
http://www.w3.org/TR/owl-ref/#sameAs-def
See also
http://www.w3.org/TR/webarch/#future-comparison
(Incidentally, I don't think the dc:identifier property is sufficient
for this, because the definition contains the "within a given context"
caveat.)
In theory, yes, it would be possible to change the DC description model
to allow multiple resource URIs per description and multiple value URIs
per statement, but
(a) that seems to increase the complexity of the description model
further (and my own feeling is that the description model is already
bordering on the over-complex)
(b) I don't think DC metadata has ever had that capability "built-in":
it has always been necessary to construct some statement to express that
the resources identified by two URIs are the same resource
Pete
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