OWL ontology for identity on the web

This paper by Valentina Presutti and Aldo Gangemi at SWAP2006 begins with a clear introduction to the issue of resource identity, and the ambiguity of the term resource itself. Then it goes on with a very smart OWL model attempting to articulate the various aspects of this concept. Maybe too smart and conceptual to become really popular, but interestingly enough, it goes against the popular Semantic Web assumption that URI can actually identify "non-addressable things", and is rather in the line of letting the referent entities outside of the identification framework.

The definitions of resource that can be found in literature show ambiguity, making the issue of handling the identification of a web resource very problematic.

Our approach restricts the nature of the web resource to that of a computational object. This choice is motivated by the fact that a resource is something that has to be addressable, and things like cars and people are not addressable for their nature. Hence, it is wrong in principle to use the same mechanism of addressing for entities that have such different sorts.

Migration to new Blogger version

I took the opportunity of this migration to change the layout template. The new one seems more readable, and anyway I was fed up with all those dots. I like this little architecture piece on the top left corner. Actually I think it's a lighthouse, since the template is called "Harbor", but it also looks to me like an observatory platform opening on the sky, "useful by its opening and central emptiness" ... well in the spirit of univers immedia.

The list of contributors does not show anymore, they have to do something about their Blogger account to be able to post again.

A couple of things I've been about lately

I've been silent here for over two months now, my blogging time devoted to the Mondeca blog in French Leçons de Choses. But there is a couple of things I've been working on, worth mentioning.

I've exchanged with Michel Biezunski on his Data Projection Model , and found out that its genericity and simplicity made it easy and straightforward to express the structure of Mondeca ITM, without the borderline hacking needed when using either OWL-RDF or XTM for the same task. Now open questions: What will happen with that model? Who will see the benefits over languages already in this space, and singularly over RDF? Who will build tools supporting it?

Been wondering if a semiotic approach could shed some light on our thoughts on referents, and came out with a RDF semiotic triangle. The URI is the signifier, the RDF description is the formalisation of the signified concept associated with the URI. The referent is out of the language and signs realm, and should stay there. In this approach, attempting to achieve a representation of the referent, even using tricks as blank resources or hubjects of any kind, is therefore a recursive trap and actually a non-sense. So any declaration of same-ness or identity of referents should be avoided. Only concepts bear identity, not their referents. From that point on, came to the idea that linking different concepts/signs (URI + RDF description) which humans consider to have more or less similar referent will take the form of processing rules, more than declarative semantics.

Thanks to Jakob Voss for this post in a long thread on public-esw-thes list, which really triggered a kind of illumination about this. As an example, trying to say that my SKOS concept a:Restaurant has the same referent as your OWL class b:Restaurant through any RDF declarative relation between those two resources shoud be avoided. But I can set in my system a functional rule expressing that any document of which subject is an instance of your b:Restaurant class will be indexed against my a:Restaurant concept. The referent is represented nowhere, but it is acting at the core of this rule.

Actually we have this very indexing rule mechanism working in some Mondeca applications, and I have submitted a paper to XTech 2007 about it. More to come if ever the paper is selected.

Lately, got interested again in triggering some process to have languages available not only as tags to use in XML, but as proper RDF resources. This is an old story tracking back to OASIS Published Subjects Technical Committees, and singularly PSI for languages. Track this topic on ESW Wiki, and see here for ongoing thread and more explanations. There again, my proposal is to forget absolute identification of a language by a URI. Concepts identified by URI are the properties and property values than can be declared for a language, and let applications decide on which properties are useful to them. No absolute rule saying that two descriptions refer to the same language.

Leçons de Choses

My blog activity lately has been dedicated to launch the new Mondeca Blog - yes it's in French. Sorry about that.

Geonames enters the Semantic Web

I'm quite happy of this. The collaboration with Marc at geonames started as a simple deal : provide the ontology, said he, and I'll provide the Web Service. So did I, and so did he. This is a fantastic Web 2.0 place to play in. It already had Web Services and wiki using Google Maps, and now he has the SW interface ...

Back to Earth

I've been quite silent here lately. Put more focus on actually working stuff than theoretical musing, and singularly on various geo-unameit technologies such as geocoding, geotagging, geo microformat, and the collaborative databases using them like geonames, wikimapia ...
Places are the most fascinating use cases when it comes to identification and description, and all those technologies and their ability to interface with each other tend to prove that information about some place can be aggregated without any consensus or explicit declaration of what this place (or a place, in general) actually is, but by providing hubs between data, and interfaces putting together data somehow relevant to this place (such as Google Earth, Google Maps API and the like). Geonames web services provide a good example of this.

In defence of 404

Following the announce on the Semantic Web list of the publication of RDF geographical codes by french INSEE, a lively debate with Dan Connolly about access vs description.