RDF-based calendaring

Jim Whitehead ejw@cse.ucsc.edu
Wed, 20 Jun 2001 15:02:09 -0700


Michael Arick, a Masters student of mine, is working closely with Libby
Miller (ILRT, Bristol Univ., UK) on an RDF schema for representing
calendaring and scheduling information. They're using the iCal data model as
a starting point, then re-casting it in RDF.

While the work is ongoing, there are some interesting intermediate results:

* The iCalendar data model as a UML diagram:
http://www.cse.ucsc.edu/~marick/iCalendarUML.html

* The RDF schema for calendaring and scheduling data:
http://www.cse.ucsc.edu/~marick/HybridCal/index.html

* Here's an SVG diagram of the schema (you'll need an SVG viewer --
http://www.adobe.com/svg/viewer/install/main.html) :
http://www.cse.ucsc.edu/~marick/HybridCal/SirpacGenerated.svg

A couple things I'm finding interesting:

* The resulting RDF schema is quite large. It is probably among the largest
RDF schema produced by anyone so far.

* Looking at the graph diagram, some kind of modularization of the
visualization is really needed. It's hard to understand what is going on
here.

* While the iCal specification has a reputation for being hard to read and
understand in full, it's not obvious that an equivalent RDF schema
specification is any clearer.

Since calendaring and scheduling is a non-trivial schema, it strikes me as
being a good testbed for Semantic Web scaling. If the SW is to achieve its
goals, it'll need to handle many different schema of similar or greater
complexity. Modularization of RDF schema would appear to be critical for
achieving large scale.  It may be possible to modularize the current schema
by splitting it into multiple chunks, each with its own namespace... more
research needed.

- Jim