First meeting of our group

Dear all,

Now that Dave offered to provide us a W3C git (thank you once again!), 
we should move on to the next point and identify the topics we want to 
work on. I set up a doodle to find the right time for a  first meeting. 
Based on your answers so far, I thought that 16:00 UCT was the best time 
for such a meeting but if you think differently just let me know and I 
will adapt the doodle:

https://doodle.com/poll/h7xrxhuwfvy8aqmu

The list of open topics we discovered so far was (note that is an open 
list, I just summarize here what I remember):

  * Provide a *formal semantics *for N3, open issues there:
      o *Implicit quantification:* scoping of universal variables and
        existential variables (blank nodes)
      o *Explicit quantification: *what is the scope of @forSome and
        @forAll? Do we want to allow any URI as variable?
      o *Meaning of built-in functions: *we need to agree on built-ins
        we want to see as part of N3 logic and formalise them.
      o *Meaning of cited formulas: *we need to agree on one
        formalisation for the meaning of cited formulas.
      o *Formalisation of a proof calculus *(but this can only be done
        after fixing the meaning of formulas).
      o *Lists: *lists are treated differently in RDF and N3 do we want
        to keep that? than we should clarify the relations of the standards.


  * To agree on formal semantics we really should focus on the expected
    *use cases* and here I would like to get some insights*. *We
    especially need to know:*
    *
      o *Which built-ins do we need?* Candidates are the ones which are
        already implemented for Cwm
        (https://www.w3.org/2000/10/swap/doc/CwmBuiltins), or the one
        identified by the RIF working group
        (https://www.w3.org/TR/rif-dtb/) or we could also look into the
        different functions which are available in SPARQL filters.
      o *How do want to use cited graphs: *There is a whole list how the
        related concept TriG could be understood
        (https://www.w3.org/TR/rdf11-datasets/). Behind these there are
        for sure applications which drove the definition*s *and I think
        it could help to understand what these were. But I also think
        that all of you have ideas how to use the concepts, so maybe we
        could create examples?*
        *
      o *How expressive does the rule reasoning need to be? *This will
        influence how we formalise the quantification, so I would like
        to know where you want to use N3 reasoning for.


  * We should also keep the *relation to other standards* close:
      o we should try to align with RDF where possible
      o do we need a JSON-LD specification?
      o what is the position towards TriG? Reification? RIF?


  * Together with the formalisation we should also discuss whether we
    provide a reference implementation together

I would like to add these topics to the git as soon as we have it, we 
can also all propose new issues, discuss them there and prioritize. I 
hope that we end up with a short list of things we all tackle together.

So, for a first step, please fill in the doodle till the end of the week.

Kind regards,
Doerthe


-- 
Dörthe Arndt
Researcher Semantic Web
imec - Ghent University - IDLab | Faculty of Engineering and Architecture | Department of Electronics and Information Systems
Technologiepark-Zwijnaarde 19, 9052 Ghent, Belgium
t: +32 9 331 49 59 | e: doerthe.arndt@ugent.be