Re: Wiki-page on EL++ and ISSUE-79

> The existing Fragments document provides an overview of various
> interesting fragments and pointers into the literature. I don't think
> that it would make sense to add a much more detailed description of
> any one fragment, at least not until we make strategic decisions on
> fragments in general. It may make sense for Bernardo to make
> editorial fixes to the existing document in response to the points
> made by Carsten below.

Yes, I think what makes sense is to make the editorial changes Ian is
proposing to the existing document, according to the issues reported by
Carsten. I will try to do so asap.

Bernardo

>
> Ian
>
>
> >
> > Thanks,
> > Alan
> >
> > On Dec 12, 2007, at 9:07 AM, Carsten Lutz wrote:
> >
> >>
> >> Dear all,
> >>
> >> as proposed by Jim, I have set up a Wiki page with details on the
> >> EL++
> >> tractable fragment of OWL 1.1 DL. You can find it at
> >>
> >> 	http://www.w3.org/2007/OWL/wiki/EL
> >>
> >> The version of EL++ given there is, in my opinion, the natural
> >> version
> >> of EL++ that comes up as a fragment of OWL 1.1 DL. It differs from
> >> the
> >> one given in Bernardo's "tractable fragments" document in a number of
> >> (mostly minor) ways. Notably,
> >>
> >> - some additional expressive power is added, such as reflexive
> >> properties,
> >>   facts, and datatypes
> >>
> >> - a nonstructural restriction is adopted to achieve tractability (the
> >>   fragment reported in Bernardo's document doesn't have it, and turns
> >>   out to be at least PSpace-hard).
> >>
> >>> From my perspective, this settles ISSUE-79 (raised by myself),
> >>> which asks
> >> for the appropriate version of EL++ that we should consider within
> >> this
> >> group.
> >>
> >> As an aside: note that my wiki page is quite long. If EL++ should
> >> become part of the standard, I feel that the document should be even
> >> more detailed. This indicates that standardizing a larger number of
> >> tractable fragments will be quite a bit of work, and produce quite
> >> long documents.
> >>
> >> greetings,
> >> 		Carsten
> >>
> >> PS: Bernardo, if you want to integrate all or some of this in your
> >>     document, please go ahead.
> >>
> >> --
> >> *      Carsten Lutz, Institut f"ur Theoretische Informatik, TU
> >> Dresden       *
> >> *     Office phone:++49 351 46339171   mailto:lutz@tcs.inf.tu-
> >> dresden.de     *
> >>
> >
> >
>
>
>


***********************************
Dr. Bernardo Cuenca Grau
Research Fellow
Information Management Group
School Of Computer Science
University of Manchester, UK
http://www.cs.man.ac.uk/~bcg
************************************

Received on Wednesday, 12 December 2007 18:08:22 UTC