status report - formal layer

I didn't make much progress on Friday over and above what I've already 
pointed to.

http://www.w3.org/2007/OWL/wiki/POWDER

I need to do other work, and hope to work on the powder stuff again 
either Thursday or Friday this week.

On the validity issue, my current thought is as follows.

- Each DR should be in its own document (at least notionally: i.e. there 
is a URL that if you do a get you get the DR - that's not to exclude the 
case where mutliple DRs are listed together in a single file, in 
addition to the individual files).
- The validity refers to the validity of the file (and hence of the 
individual DR).
- The subclass relationship corresponding to a DR  necessarily follows, 
even if the DR is invalid (But invalid DRs may or may not be true).
- To work out the formal meaning of a set of powder files, the first 
step is to take the RDF merge of the valid files, and then take the RDF 
semantics for that merge.

This follows the named graphs paradigm, in leaving 'difficult' stuff 
(e.g. time) outside the formal treatment, but providing a pragmatic 
treatment (ignore invalid files).

I still need to think through the relationship with packages.
Unless the discussion indicates that the above approach is misguided, 
I'll write it up, as part of the proposed formal treatment, and include 
it in the wiki page.

Jeremy

Received on Monday, 14 January 2008 14:22:23 UTC