URIs for languages

I've eventually given up trying representing hubjects at all, at least for the moment. I had a serious try at it at lingvoj.org. But after discussions in the Linking Open Data forum, I eventually surrendered and published the languages description in a way conformant to W3C recommandations for Semantic Web architecture, with content negociation, 303 redirects and the like. I've even suppressed the previous post here saying otherwise, which would be now full of dead links and would bring about confusion.

So we'll see how this flies. Feed your favourite tool with the URI http://www.lingvoj.org/lang/zh, and figure by yourself if it provides a useful description of the Chinese language, both for humans and machines.

As simple as possible ...

Those days Planet RDF is buzzing with a bunch of interesting responses to Danny Ayers' provocative question about alternatives to the Semantic Web (if possible simpler than the original stuff). Getting rid of artificial complexity gathered around the basically so-simple RDF model is of course the main preoccupation, and of course, the lack of canonical serialization in XML is seen as a major obstacle to adoption. At SemEmergence, Seth Ladd is crying for it:

Please, W3C, create a standard RDF serialization that elevates RDF as a first class citizen of XML. Everyone else has a schema, why can't we?

Having passed (too much) time those days struggling with the yet-another-serialization syndrom in the latest versions of SWOOP and Protégé, I could not agree more. But waiting for such a (most unlikely) W3C delivery, alternatives solutions pop up and are worth looking at.
Phil Jones pushes the notion of SynWeb, which he defines as a web which doesn't need "key identifiers".

The difference is that the knowledge needed to give semantics to the data resides in the programs which do the combining, rather than in a schema which has been prepared earlier.

No absolute meaning of data, no absolute identifiers, semantics in the application context? Certainly close to our current ramblings on perspectives and aspects.

The simplest and most radical alternative to-date is certainly Phil Dawes' tagtriples, a simple text format for triple statements. Forget URIs, namespaces, XML and the like. Identification is local to a graph (an ordered collection of statements), as indicated in the Tagtriples Model and Semantics (don't run away, that is really as simple as can be).

All occurances [sic] of a particular symbol in a graph must denote the same meaning. [...] The same symbol used in different graphs may or may not denote the same meaning - it is up to the consumer of the information to interpret how the symbol/meanings correspond.

Thinking about RDF and Topic Maps

Danny Ayers, in this blog entry, talks about issues related to representations in RDF that speak to issues I have thought about for a while now. I think that now is a good time to start a dialog between the RDF tribe and the Topic Maps tribe. It's a double-edged knife, one that cuts both ways, looking at the true nature of the inquiries of each tribe.

I like to think about it this way: the core of the topic maps inquiry is to
satisfy a couple of important use cases: finding and reminding. In
those two use cases lie two primitive notions: subject identity and
names for things. Those are the two primitives that topic maps place
front and center, whereas, it seems to me, OWL emphasizes inferencing in
subsumption hierarchies, relegating subject identity to "proper use of URIs". I like to think about subject identity in the same terms a lawyer might do so in a court case. There, properties of the subject, more so than some URI, become all important. A trial might turn on something as trivial as shoes worn on some particular day. As topic maps are evolving, particularly in the case of the TMRM (topic maps reference model), we are seeing more emphasis placed on comparable subject properties than on precise URIs, which, in many cases, do not (yet) exist. We are seeing the evolution of the ability to "confer" identity on a subject according to circumstances. I think this line of inquiry can map directly into rdf work.

Topic maps (indeed, "subject maps") add one important consideration
outside subject identity and names for things: a guarantee that any
proxy for any subject (aka Topic), is the one place you need to go (in
*this* map) to find all that is knowable about that subject.

The knife cutting in the other direction suggests that, at the implementation level, topic maps could evolve along lines suggested from rdf work. Indeed, some of my own work involves the use of Jena coupled with JDBM for a backside.

Ontology Definition Metamodel

Certainly a major step towards semantic interoperability of Topic Maps, RDF, OWL, UML, Common Logic ... Really worth downloading and reading at length.

RDF/Topic Maps Interoperability Task Force

In his today's deviant chronicle, Edd Dumbill is wondering if the Semantic Web dreamers could not turn out to be right after all:

The topics of XML-oriented programming languages and the Semantic Web have been targets of mockery in their time, so this week I'm asking whether the true believers might be right.

And further on:

The unthinkable rapprochement between topic maps and RDF has occurred, signified by the formation of the W3C RDF/Topic Maps Interoperability Task Force. The task force is part of the Semantic Web Best Practices and Deployment Working Group. The last time I was with the majority of the people listed as members of the task force, it was in a very pleasant drinking establishment in Amsterdam. It's nice to think that the bonhomie of that evening has persisted into forming the basis of the task force.

Concise Bounded Descriptions

Thanks to a post by Danny Ayers, I got a chance to look at Nokia's latest contribution to open source software, Uriqa. Here's the requisite quote. I hope to have more to say about this later.

This document defines a concise bounded description of a resource in terms of an RDF graph [5], as a general and broadly optimal unit of specific knowledge about that resource to be utilized by, and/or interchanged between, semantic web agents.

Given a particular node in a particular RDF graph, a concise bounded description is a subgraph consisting of those statements which together constitute a focused body of knowledge about the resource denoted by that particular node.