- From: Ian Horrocks <ian.horrocks@comlab.ox.ac.uk>
- Date: Sat, 21 Feb 2009 09:49:49 +0000
- To: Ivan Herman <ivan@w3.org>
- Cc: Michael Schneider <schneid@fzi.de>, W3C OWL Working Group <public-owl-wg@w3.org>
I corrected a small typo (mean to means), but otherwise looks fine. Ship it! Thanks, Ian On 21 Feb 2009, at 08:13, Ivan Herman wrote: > We seem to have discussed this one to death:-)... anyway, I found the > discussion on the FS useful for me at least! > > I have modified the Wiki site with the draft answer. I did add a half > sentence, though, to answer to the question; the last sentence now > reads: > > [[[ > In the example you mentioned, for example, the "_:1" simply > represents a > blank node in the RDF graph, and this is indeed the only syntactic > mean > to define a blank node. > ]]] > > See you soon! > > Ivan > > Ian Horrocks wrote: >> I'm pretty sure that his main concern was w.r.t. backwards >> compatibility. I suggest that we simply try the answer below and see >> what he says. >> >> Ian >> >> On 20 Feb 2009, at 19:29, Ivan Herman wrote: >> >>> Hm, you made me uncertain:-( Re-reading his comments again I wonder >>> whether his question is not about AS but whether it is possible, in >>> the FS, to define anonymous nodes _without_ explicit naming. In >>> which >>> case the answer should be a 'no'... >>> >>> Ivan >>> >>> Ian Horrocks wrote: >>>> It wasn't obvious to me that Frank was concerned with the AS. >>>> When he >>>> said that "it's not clear from the doc. whether the OWL1 syntax is >>>> still allowed", I imagined that he was really concerned about >>>> the RDF >>>> syntax and the expressivity of the language. As I said in my email, >>>> the AS has changed in many ways, and it seemed odd that Frank would >>>> single out this one. >>>> Anyway, I don't suppose that it would hurt to put back the >>>> paragraph >>>> on AS, but I suggest putting it after the one about backwards >>>> compatibility of the RDF. The result would be: >>>> Dear Frank, >>>> Thank you for your comment >>>> <http://lists.w3.org/Archives/Public/public-owl-comments/2009Jan/ >>>> 0037.html> >>>> >>>> on the OWL 2 Web Ontology Language last call drafts. >>>> We also note the 'addendum' to your original comment in >>>> <http://lists.w3.org/Archives/Public/public-owl-comments/2009Feb/ >>>> 0014.html> >>>> >>>> And we thank you for helping us avoiding further confusion on this >>>> issue. >>>> It is important to note that nothing changed on the RDF side, >>>> and that >>>> the treatment of anonymous individuals in OWL 2 is fully backwards >>>> compatible with that in OWL 1. Even on the structural syntax >>>> side, there >>>> is no change in expressive power, but we restructured the syntax >>>> to be >>>> in closer correspondence with RDF graphs to make it clearer that >>>> anonymous individuals are in direct correspondence with blank >>>> nodes. In >>>> the example you mentioned, for example, the "_:1" simply >>>> represents a >>>> blank node in the RDF graph. >>>> Concerning the usability of AS in OWL 2: if used as an exchange >>>> syntax then, of course, OWL 1 ontologies written in AS may be input >>>> to OWL 2 tools and remain valid ontologies. But we must emphasize >>>> that this is an issue of the tool providers: the only _required_ >>>> exchange syntax for OWL 2 ontologies being RDF/XML, it is up to the >>>> tools to decide whether they would accept ontologies serialized >>>> in AS >>>> (or in FS, for that matter). >>>> We agree this isn't made very clear in the documents, and we >>>> will try to >>>> improve the presentation. For example, we plan to add some >>>> explanatory >>>> text into the New Features and Rationale document on the change of >>>> syntax. >>>> We hope this answers your concerns on this particular issue. >>>> On 20 Feb 2009, at 12:10, Ivan Herman wrote: >>>>> Ian, >>>>> >>>>> I do not mind using this text, but Frank explicitly asked >>>>> whether AS is >>>>> still usable. Why did you leave that part out? >>>>> >>>>> Ivan >>>>> >>>>> P.S. As an aside, although the text on FS/FOL came from an earlier >>>>> version of the draft, as written by Bijan, I must admit that this >>>>> argument seemed to be valid to me. The only way I can explain >>>>> myself >>>>> the >>>>> order of the various arguments and parameters in the language >>>>> is when I >>>>> look at the way the same formulae would be written in FOL. But >>>>> that may >>>>> be only me, I do not mind taking that out... >>>>> >>>>> Ian Horrocks wrote: >>>>>> Another issue with the proposed response is that I don't think it >>>>>> clearly answers Frank's main concern (as I understand it), >>>>>> which is >>>>>> backwards compatibility of the RDF syntax. I also wonder why >>>>>> you talk >>>>>> about the FS being closer to FOL syntax -- I don't recall this >>>>>> being a >>>>>> motivation and I doubt that it is relevant to Frank or to (m)any >>>>>> other >>>>>> people. Finally, w.r.t. the structural syntax, this has been >>>>>> changed in >>>>>> *many* respects, so I doubt that compatibility of the structural >>>>>> syntax >>>>>> is particularly relevant here. >>>>>> >>>>>> I therefore suggest the following response: >>>>>> >>>>>> >>>>>> Dear Frank, >>>>>> >>>>>> Thank you for your comment >>>>>> >>>>>> <http://lists.w3.org/Archives/Public/public-owl-comments/ >>>>>> 2009Jan/0037.html> >>>>>> >>>>>> on the OWL 2 Web Ontology Language last call drafts. >>>>>> >>>>>> We also note the 'addendum' to your original comment in >>>>>> >>>>>> <http://lists.w3.org/Archives/Public/public-owl-comments/ >>>>>> 2009Feb/0014.html> >>>>>> >>>>>> >>>>>> And we thank you for helping us avoiding further confusion on >>>>>> this >>>>>> issue. >>>>>> >>>>>> It is important to note that nothing changed on the RDF side, >>>>>> and that >>>>>> the treatment of anonymous individuals in OWL 2 is fully >>>>>> backwards >>>>>> compatible with that in OWL 1. Even on the structural syntax >>>>>> side, >>>>>> there >>>>>> is no change in expressive power, but we restructured the >>>>>> syntax to be >>>>>> in closer correspondence with RDF graphs to make it clearer that >>>>>> anonymous individuals are in direct correspondence with blank >>>>>> nodes. In >>>>>> the example you mentioned, for example, the "_:1" simply >>>>>> represents a >>>>>> blank node in the RDF graph. >>>>>> >>>>>> We agree this isn't made very clear in the documents, and we will >>>>>> try to >>>>>> improve the presentation. For example, we plan to add some >>>>>> explanatory >>>>>> text into the New Features and Rationale document on the >>>>>> change of >>>>>> syntax. >>>>>> >>>>>> We hope this answers your concerns on this particular issue. >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On 20 Feb 2009, at 11:08, Michael Schneider wrote: >>>>>> >>>>>>> Ivan wrote: >>>>>>> >>>>>>>> For example, one can refer to anonymous/blank nodes from >>>>>>>> more than one place, hence a larger class of RDF graphs can be >>>>>>>> expressed >>>>>>>> in FS. >>>>>>> >>>>>>> I would like to see an example for something that can now be >>>>>>> written >>>>>>> in the Functional Syntax, for which there was no >>>>>>> corresponding way to >>>>>>> express it in the old Abstract Syntax. The global syntactic >>>>>>> restrictions in Section 11.2 of the Structural Spec are pretty >>>>>>> restrictive, AFAICT. >>>>>>> >>>>>>> Michael >>>>>>> >>>>>>> -- >>>>>>> Dipl.-Inform. Michael Schneider >>>>>>> Research Scientist, Dept. Information Process Engineering (IPE) >>>>>>> Tel : +49-721-9654-726 >>>>>>> Fax : +49-721-9654-727 >>>>>>> Email: schneid@fzi.de >>>>>>> WWW : http://www.fzi.de/ipe/eng/mitarbeiter.php?id=555 >>>>>>> >>>>>>> ================================================================ >>>>>>> ============== >>>>>>> >>>>>>> >>>>>>> >>>>>>> FZI Forschungszentrum Informatik an der Universität Karlsruhe >>>>>>> Haid-und-Neu-Str. 10-14, D-76131 Karlsruhe >>>>>>> Tel.: +49-721-9654-0, Fax: +49-721-9654-959 >>>>>>> Stiftung des bürgerlichen Rechts >>>>>>> Stiftung Az: 14-0563.1 Regierungspräsidium Karlsruhe >>>>>>> Vorstand: Prof. Dr.-Ing. Rüdiger Dillmann, Dipl. Wi.-Ing. >>>>>>> Michael >>>>>>> Flor, >>>>>>> Prof. Dr. rer. nat. Dr. h.c. Wolffried Stucky, Prof. Dr. rer. >>>>>>> nat. >>>>>>> Rudi Studer >>>>>>> Vorsitzender des Kuratoriums: Ministerialdirigent Günther >>>>>>> Leßnerkraus >>>>>>> >>>>>>> ================================================================ >>>>>>> ============== >>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>> >>>>> -- >>>>> >>>>> Ivan Herman, W3C Semantic Web Activity Lead >>>>> Home: http://www.w3.org/People/Ivan/ >>>>> mobile: +31-641044153 >>>>> PGP Key: http://www.ivan-herman.net/pgpkey.html >>>>> FOAF: http://www.ivan-herman.net/foaf.rdf >>>>> >>> >>> -- >>> >>> Ivan Herman, W3C Semantic Web Activity Lead >>> Home: http://www.w3.org/People/Ivan/ >>> mobile: +31-641044153 >>> PGP Key: http://www.ivan-herman.net/pgpkey.html >>> FOAF: http://www.ivan-herman.net/foaf.rdf >>> >> > > -- > > Ivan Herman, W3C Semantic Web Activity Lead > Home: http://www.w3.org/People/Ivan/ > mobile: +31-641044153 > PGP Key: http://www.ivan-herman.net/pgpkey.html > FOAF: http://www.ivan-herman.net/foaf.rdf >
Received on Saturday, 21 February 2009 09:50:27 UTC