- From: Rouquette, Nicolas F (316A) <nicolas.f.rouquette@jpl.nasa.gov>
- Date: Sun, 6 Dec 2009 21:30:42 -0800
- To: "public-owl-comments@w3.org" <public-owl-comments@w3.org>
- Message-ID: <C741D302.EB2C%Nicolas.F.Rouquette@jpl.nasa.gov>
Below are three comments about 11.2 in http://www.w3.org/TR/2009/REC-owl2-syntax-20091027/#The_Restrictions_on_the_Axiom_Closure 1) Define the forest of anonymous individuals. Michael Schneider raised questions about this a few months ago: http://lists.w3.org/Archives/Public/public-owl-wg/2009May/0362.html Based on the description & example, I understand that, given a set of axioms Ax, F is a directed graph with vertices V and edges E such that: * V = the set of all anonymous individuals appearing in the syntactic definition of any of the axioms in Ax. * E = the set of all pairs (_:x, _:y) such that _:y is directly a child of _:x Please clarify: * what makes an anonymous individual a root of F? * what makes an anonymous individual _:y a child of another anonymous individual _:x? 2) Example on "Restrictions on Datatypes" Since the restriction involves a strict partial order, I suggest replacing the following: For example, it can be readily verified that the order < given below fulfills the above conditions. xsd:string < a:SSN < a:TIN < a:TaxNumber With this: For example, it can be readily verified that the partial order <1 given below fulfills the above conditions. xsd:string <1 a:SSN <1 a:TaxNumber xsd:string <1 a:TIN <1 a:TaxNumber The total order <2 given below fulfills the above conditions and is also consistent with the partial order <1 given above. xsd:string <2 a:SSN <2 a:TIN <2 a:TaxNumber 3) Restriction on Simple Roles The first and second examples would be clearer if you provided the strict partial order instead of a total order and indicated the provenance of the ordering constraints to the axioms. For the first example, I suggest replacing: For example, it can be readily verified that the order < given below fulfills the above conditions. a:hasFather < a:hasBrother < a:hasUncle < a:hasWife < a:hasAuntInLaw With: For example, it can be readily verified that the partial order <1 given below fulfills the above conditions. a:hasFather <1 a:hasUncle # 1st axiom a:hasBrother <1 a:hasUncle # 1st axiom a:hasUncle <1 a:hasAuntInLaw # 2nd axiom a:hasWife <1 a:hasAuntInLaw # 2nd axiom The total order <2 given below fulfills the above conditions and is consistent with the partial order <1 given above. a:hasFather <2 a:hasBrother <2 a:hasUncle <2 a:hasWife <2 a:hasAuntInLaw For the second example, since the axioms are symmetric, it is ambiguous which ordering constraints corresponds to which axiom. I suggest replacing: To verify this condition formally, note that, for < to satisfy the third subcondition of the third condition, we need a:hasUncle < a:hasBrother and a:hasBrother < a:hasUncle; ... with: To verify this condition formally, note that, for < to satisfy the third subcondition of the third condition, we need a:hasUncle < a:hasBrother (2nd axiom) and a:hasBrother < a:hasUncle (1st axiom); ... - Nicolas.
Received on Monday, 7 December 2009 05:31:27 UTC