Rinke Hoekstra

Yesterday I was playing around with Peter Mika’s BuRST to create an RSS 1.0 feed of the publications of the Leibniz Center. We already use bibtex2html to generate a weekly update of our publications page.
BuRST services are used, amongst others, by the openacademia.org project to generate RSS feeds of the documents in their RDF triple store. See also Ivan Herman’s blog post on this subject.

However, the RSS generated by BuRST is targeted at RDF-aware clients, and does not contain the Dublin Core metadata used by RSS viewers such as Thunderbird, Google Reader, Yahoo Pipes or Mail (Leopard) to show human readable information.

The BuRST service at openacademia.org uses a BibTex to RDF perl script by Michel Klein to generate a SWRC compliant RDF description of bibliographies stored using the BibTeX format. I have modified his script in such a way that it can now generate simple lightweight RSS representations of BibTeX files.

Voila: bib2rss.pl

You can download it, and use it at your choosing (Michel has GPL-ed the original).

Some examples:

Publications of the Leibniz Center, as RSS 1.0 feed
http://draco.leibnizcenter.org/cgi-bin/bib2rss.pl?url=http://svn.leibnizcenter.org/svn/LeibnizBib/trunk/leibniz.bib

Publications of the Leibniz Center, as RSS 1.0 feed with title and description
http://draco.leibnizcenter.org/cgi-bin/bib2rss.pl?url=http://svn.leibnizcenter.org/svn/LeibnizBib/trunk/leibniz.bib&title=LeibnizPubs&description=Publications%20of%20the%20Leibniz%20Center

Some issues:

• How to determine the dc:date of a publication RSS-item? Currently: all publications are dated on the first of January of every year. Dates in RSS are an issue anyway.
• Some RSS readers (Mail, Yahoo Pipes) do not show the dc:creator of RSS 1.0 items
• Apple Mail seems to disregard any dc:date in 2001 (weird!)
• bib2rss.pl depends on the Text::BibTeX module of the btOOL library.

Bijan Parsia introduced the ideas of a SPARQL-like language that uses DL constructs at the ESWC 2007 OWLED workshop. The guys at Clark&Parsia really got busy, and the first implementation of SPARQL-DL will be introduced as part of Pellet.

While reading the more recent post, about query optimization, I wondered whether it is foreseen that SPARQL-DL will support CONSTRUCT queries.

One of the bigger problems in OWL knowledge-base manipulation is that it is often necessary to assert new individuals or classes based on assertions already available in the KB, e.g. in computing the outcome of some process or change. This is where SPARQL-DL constructs would really come in handy, as we can then use variables to both match and construct OWL definitions. Regular SPARQL doesn’t really help, as it only allows you to query and construct an RDF graph.

Yesterday I gave a presentation at our monthly department meeting about the nuts ‘n bolts of the SemanticWeb. This was to give them a taste of its coolness.

If you’re interested, here it is: semweb-nuts-bolts.pdf