RE: OWL and Published Subjects

["Bernard Vatant" <bernard.vatant@mondeca.com>]

If you want to follow up with this thread, please don't hit "reply to all"
on the previous message ...
public-webont-comments-request@w3.org is *not* the address for OWL
comments. My mistake, sorry about that.

The valid address is public-webont-comments@w3.org, with archives at
http://lists.w3.org/Archives/Public/public-webont-comments/

This thread at
http://lists.w3.org/Archives/Public/public-webont-comments/2003May/0013.htm
l

Thanks



> -----Message d'origine-----
> De : Bernard Vatant [mailto:bernard.vatant@mondeca.com]
> Envoyé : mardi 6 mai 2003 17:10
> À : public-webont-comments-request@w3.org
> Cc : tm-pubsubj
> Objet : OWL and Published Subjects
>
>
>
> Please find below some comments about expected interoperability
> of OWL, Topic Maps in general and Published Subjects in particular.
>
> Disclaimer : Those comments are engaging only their author, and
> must not be considered as "official" feedback neither from the
> Topic Maps standard working group (namely ISO/IEC
> JTC1/SC34-WG3), nor from the OASIS Published Subjects TC that I
> happen to chair. Interoperability with OWL has not been put on
> the agenda of those groups so far. That is something I
> personally deplore, and that seems due to many reasons, among
> which: lack of task force, "not developed here" syndrom, and
> last but least lack of formal foundation for Topic Maps, making
> the whole TM community uneasy about the issue.
>
> Before going to the specific point of Published Subjects, I want
> to say that I have been working for some time now, on an OWL
> expression for Topic Maps, trying to consider them as some
> specific kind of ontology - which I think it should be, no more,
> no less. Although TM gurus have always claimed them to be
> ontology-neutral, this is IMO wrong, the only way to be
> ontology-neutral being to keep silent. And Topic Maps folks are
> known to be very talkative :)
> Difficulties that I meet to achieve that task seem to come, not
> from the lack of expressive power of OWL, but from the lack of
> consensus for what are the foundations of Topic Maps, default a
> consensus on their formal model. "What is a topic map?" is still
> an open issue it seems. A good reference for the state of
> reflection in TM community vs RDF and OWL is the paper from Lars
> Marius Garshol "Living with Topic Maps and RDF" that he will
> present this week at XML Europe:
> http://www.ontopia.net/topicmaps/materials/tmrdf.html.
>
> Concerning Published Subjects, I will show below that OWL
> documents could easily meet the Requirements and Recommendations
> for Published Subjects expressed in Deliverable 1 of OASIS
> PubSubj TC [1], about to be adopted as a TC specification
> (hopefully) in London next Friday:
> http://www.ontopia.net/tmp/pubsubj-gentle-intro.htm.
>
> - Requirement 1:
> "A Published Subject Identifier must be a URI."
>
> Sor far, so good. Any URI identifying an OWL class, property or
> individual can be used as a Subject Identifier.
>
> - Requirement 2:
> "A Published Subject Identifier must resolve to an
> human-interpretable Published Subject Indicator."
>
> Are OWL ontologies human-interpretable? Depending on humans, of
> course. But providing sensible use of labels and comments, an
> OWL element can be a very accurate Subject Indicator for the
> class, property, or individual it represents.
>
> - Requirement 3:
> "A Published Subject Indicator must explicitly state the unique
> URI that is to be used as its Published Subject Identifier."
>
> This is more tricky. Take for example
> http://www.mondeca.com/owl/univ1_0.xml#Employee
> Extracted from an attempt of re-writing a DAML university
> ontology in OWL)
>
> <owl:Class rdf:ID="Employee">
>   <owl:sameAs
> rdf:resource="http://www.mondeca.com/owl/general1_0.xml#Employee" />
> </owl:Class>
>
> Here both http://www.mondeca.com/owl/univ1_0.xml#Employee and
> http://www.mondeca.com/owl/general1_0.xml#Employee could be
> valid subject identifiers. So, to be conformant to Requirement
> 3, either a general rule should be set, or a specific explicit
> property should be set like psi:identifier, in the following way.
>
> <owl:Class rdf:ID="Employee">
>     <owl:sameAs
> rdf:resource="http://www.mondeca.com/owl/general1_0.xml#Employee" />
>     <psi:identifier
> rdf:resource="http://www.mondeca.com/owl/univ1_0.xml#Employee" />
> </owl:Class>
>
> This is to be discussed and settled, but the expressive power is
> here. Note that the "sameAs" declaration leads to the important
> notion of equivalent identifiers. A topic map application should
> be able to make sense of it by aggregating on a single topic
> node its various subject identifiers in various ontologies.
>
> - Recommendation 1:
> "A Published Subject Indicator should provide human-readable
> metadata about itself."
>
> This can be achieved by using specific DatatypeProperties,
> either at the element level or at the ontology level, like the
> dc elements that can be found in the above quoted ontology. Note
> that the TC has not decided yet what kind of metadata are
> relevant, but there again the expressive power of OWL can
> support a large variety of those.
>
> - Recommendation 2:
> "A Published Subject Indicator may provide machine-processable
> metadata about itself."
>
> No comment here. Metadata expressed in OWL are obviously
> machine-processable.
>
> - Recommendation 3:
> "Metadata defined in Recommendations 1 and 2 should be
> consistent, but need not necessarily be equivalent."
>
> I figure human-readable metadata here being only a transcription
> of OWL information in a more human-readable format than rdf.
>
> - Recommendation 4:
> "A Published Subject Indicator should indicate that it is
> intended to be used as a PSI."
>
> This can be specified in the ontology header.
>
> - Recommendation 5:
> A Published Subject Indicator should identify its publisher.
>
> There again this information can be included in the ontology header.
>
> In conclusion, I consider OWL as a very convenient format for
> expression of Published Subjects. Moreover, providing the few
> points quoted below are cleraly settled, it could be possible to
> have a recommendation for "PSI-in-OWL", approved both by OASIS
> PubSubj TC as conformant to its Requirements and
> Recommendations, and by OWL-WG as a recommended application of OWL.
>
> Again, I insist this is only so far a personal roadmap, I will
> put it on the OASIS PubSubj TC agenda and see what happens
> there, and it's up to OWL-WG to see if it also fits iis agenda.
>
> Thanks for your attention
>
> Bernard
>
> Bernard Vatant
> Senior Consultant
> Knowledge Engineering
> Mondeca - www.mondeca.com
> bernard.vatant@mondeca.com
>
> [1] Complete archives of PubSubj TC work are temporarily at
http://www.mondeca.com/pubsubj/
The official OASIS TC site is under reconstruction, due to CMS migration,
at:
http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=tm-pubsubj