Category Archives: OWL

Visit Revisited

A few days ago, Norman Walsh was kind enough to let me know that there was something wrong with the way I had put together the visit vocabulary.

It turned out that I had mixed together some URIs while surfing around the DAML vocabularies, and the URIs I used to identify each of the states were wrong — the right ontology is

The visit vocabulary has been updated to reflect this, and the WordPress plugin Semantic Visits has been fixed, you should upgrade if at all possible.

In addition to the fixes, it has been clarified that the right ISO 3166 country code for the United Kingdom is “GB”. This warranted a fix (or more precisely an addition) in the image generation code at MyWorld66, and Douwe Osinga was quick to respond — it now accepts “GB” as well as “UK” (for backwards compatibility reasons only, use “GB” from now on), thanks!

While I was twiddling, I added support for Canadian provinces — also supported by MyWorld66’s Visited Canadian Provinces and a DAML ontology for Canadian States and Teritories, for those that have had the privilege of visiting those parts of the world.

This last part turned out to be a little harder than expected, as the Canadian regions are divided into states and territories, and that required some investigations into OWL — I think I got it right, but if not you’ll likely see yet another correction soon…

Also, it turned out that there was an issue with the terms used to indicate the code, name, and other state properties — the terms are defined in the general DAML State Ontology as e.g., but in the DAML US Region and State Ontology and the DAML ontology for Canadian States and Teritories they are used as e.g.

I’m still not sure whether the error is because of a typo with regards to the default namespace declaration, or if it’s a misunderstanding of the semantics of owl:imports (actually daml:imports). In any case, I have decided not to propagate the error, so the WordPress Plugin and the vocabulary documentation uses the properties that are defined — but not used until now.