- From: Paul Tyson <phtyson@sbcglobal.net>
- Date: Fri, 24 Apr 2020 10:58:16 -0500
- To: Mikael Pesonen <mikael.pesonen@lingsoft.fi>
- Cc: Pascal Hitzler <phitzler@googlemail.com>, semantic-web@w3.org
> On Apr 24, 2020, at 09:12, Mikael Pesonen <mikael.pesonen@lingsoft.fi> wrote: > > > Thanks Pascal, saves lot's of time if this is not possible by normal OWL DL means. That PDF looks like worth atleast trying to understand. > > Followup question to forum: how does one continue usually when reasoning capabilities hit the wall? SWRL and SPARQL queries are the next steps? > In my experience, “reasoning” is not as useful for practical business problems as directly implementing relevant business rules. A path that worked well for me was: RIF -> SPARQL -> whatever Starting with RIF provided greater visibility for business rules and all the other benefits of an open exchange format: documentation, reuse, repurposing, .... Regards, —Paul > > >> On 24/04/2020 17.01, Pascal Hitzler wrote: >> You probably find more about these matter than you care about here: http://people.cs.ksu.edu/~hitzler/resources/publications/OWL-Rules-2011.pdf >> >> But let me break down your example. >> >> you want to say something like the following: >> >> A(x) AND p1(x,y) AND C(y) AND p2(y,z) AND B(z) AND p4(w,z) AND D(w) AND p3(x,w) --> E(x) >> >> And essentially you want to know whether there is anything in the class E. >> >> With the rolification technique in the above referenced paper, yo would come up with the following to express the axiom: >> >> A equiv exists R_A.Self >> B equiv exist R_B.Self >> C equiv exists R_C.Self >> D equiv exists R_D.Self >> R_A o p1 o R_C o p2 o R_B o p4- o R_D o p3- subPropertyOf R >> exists R.Self subClassOf E >> >> Now, these six axioms *syntactically* translated into first-order predicate logic do the trick. >> >> HOWEVER, you would use Self with a non-simple role, which is not allowed under OWL DL. >> >> So the short answer is: it doesn't look like it's possible. >> >> The above paper discusses a construct called nominal schemas, which is (very complex) syntactic sugar on top of OWL, an which allows you to express the rule above, provided that the variable x can bind only to individuals actually occurring in the knowledge base. >> >> Best Regards, >> >> Pascal. >> > > -- > Lingsoft - 30 years of Leading Language Management > > www.lingsoft.fi > > Speech Applications - Language Management - Translation - Reader's and Writer's Tools - Text Tools - E-books and M-books > > Mikael Pesonen > System Engineer > > e-mail: mikael.pesonen@lingsoft.fi > Tel. +358 2 279 3300 > > Time zone: GMT+2 > > Helsinki Office > Eteläranta 10 > FI-00130 Helsinki > FINLAND > > Turku Office > Kauppiaskatu 5 A > FI-20100 Turku > FINLAND > >
Received on Friday, 24 April 2020 15:58:34 UTC