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"RDF syntax is based on a mathematical abstraction: an RDF graph is defined However ... Note that the Aggregation is not a Named Graph, it's a subclass I agree that a metadata record is a reasonable (summary) representation of So, in order to talk about the description in RDF it needs a URI too, URI-R, Does that help? Rob On Fri, Aug 15, 2008 at 1:49 AM, Jeff Young <jyoung.o...@gmail.com> wrote: It's not the AWWW that says this, but the fine print in the Named Graph
> I can believe that AWWW recognizes the possibility of resources
> without bitstreams, but I will be surprised if it dictates that an RDF
> graph is such a resource. It's difficult to imagine why a set of
> triples can't be a content-negotiable resource.
specification:
as a set of
triples. These graphs are represented by documents which can be retrieved
from URIs
on the Web. Often these URIs are also used as a name for the graph, for
example with
an owl:imports. _____To avoid confusion between these two usages we
distinguish between
Named Graphs and the RDF graph that the Named Graph encodes or
represents._____
A Named Graph is an entity with two functions name and rdfgraph defined on
it which
determine respectively its name, which is a URI , and the RDF graph that it
encodes
or represents. These functions assign a unique name and RDF graph to each
Named
Graph, but Named Graphs may have other properties; and named graphs may be
concrete
resources rather than set-theoretic abstractions." [ __ emphasis added]
of dcmitypes:Collection.
The Named Graph is the Resource Map.
an object, however that's not the model that the AWWW (sometimes rather
clumsily) gives us. Instead, we have a Collection of Resources (the
Aggregation) which needs an identifier. We then currently describe that
Collection using a Named Graph called a Resource Map, but there's no reason
that other people couldn't re-use the Aggregation identifier and describe it
with another format. It would be outside the scope of ORE, but a perfectly
valid re-use of the URI coined for the aggregation. When we assert
statements about the aggregation, it's the abstract 'work' if you like, not
the specific set of triples which we currently use to describe it.
which is what makes it a Named Graph rather than just a bunch of triples.
And where better to get a representation of that graph than from its URI!
Thus we have the redirection mechanism, as per AWWW in order to get from the
Aggregation (Collection, Work, Abstract Item of Interest) to the Resource
Map (Description, Named Graph, Concrete Representation)