To quote the VoCamp wiki:
VoCamp is a series of informal events where people can spend some dedicated time creating lightweight vocabularies/ontologies for the Semantic Web/Web of Data. The emphasis of the events is not on creating the perfect ontology in a particular domain, but on creating vocabs that are good enough for people to start using for publishing data on the Web.
I admit that I went into the event slightly unprepared, as I didn't have any firm ideas about any specific vocabulary I wanted to work on, but happy to join in with anyone who was working on anything of interest. Some of the outputs of the various groups are listed on the wiki page.
As well as work on specific vocabularies, the opening discussions highlighted an interest in a small set of more general issues, which included the expression of "structural constraints" and "validation"; broader questions of collecting and interpreting vocabulary usage; representing RDF data using JSON; and the features available in OWL 2. Friday morning was set aside for those topics, which meant I had an opportunity to talk a little bit about the work being done within the Dublin Core Metadata Initiative on "Description Set Profiles", which I've mentioned in some recent posts here. I did hastily knock up a few slides, mainly as an aide memoire to make sure I mentioned various bits and pieces:
There was a useful discussion around various different approaches for representing such patterns of constraints at the level of the RDF graph, either based on query patterns, or on the use of OWL (with a "closed-world" assumption that the "world" in question is the graph at hand). Some of the new features in OWL 2, such as capabilities for expressing restrictions on datatypes seem to make it quite an attractive candidate for this sort of task.
I was asked about whether we had considered the use of OWL in the DCMI context. IIRC, we decided against it mostly because we wanted an approach that built explicitly on the description model of the DCMI Abstract Model (i.e. talked in terms of "descriptions" and "statements" and patterns of use of those particular constructs), though I think the "open-world" considerations were also an issue (See this piece for a discussion of some of the "gotchas" that can arise).
Having said that, it would seem a good idea to explore to what extent the constraint types permitted by the DSP model might be mapped into other form(s) of expressing constraints which might be adopted.
All in all, it was a very enjoyable couple of days: a fairly low-key, thoughtful, gentle sort of gathering - no "pitches", no prizes, no "dragons" in their "dens", or other cod-"bizniz" memes :-) - just an opportunity for people to chat and work together on topics that interested them. Thank you to Tom & Damian & Libby for doing the organisation (and introducing me to a very nice Chinese restaurant in Bristol on the Thursday night!)