RE: Mustangs vs myMustang

Hi Valentin and Dick,

 

I came with this question because in our ISO 15926 modelling team we have
been puzzled by this for some time. Ford Company and myMustang are
individuals in space-time, the Class "Mustangs" isn't. 

 

If I have understood RDF and OWL well, Ford Company and myMustang are in
defined in RDF, and the Class "Mustangs" is defined in OWL (as a subClassOf
Car). That creates a kind of "cross-over" Property isManufacturerOf  between
the RDF domain (Ford) and the OWL domain (Mustangs) that is not allowed.

 

So, we create an owl:Thing "Mustangs" that is typed with the owl:Class
"Mustangs", and is the "extent" of that Class. Right? Now we need to create
the owl:Property isManufacturerOf, as Dick has illustrated below. However,
defining an intersection in RDF is not allowed.  myMustang isn't a Class.

 

How do we untie this knot?

 

Regards,

Hans

 

PS to Dick: CarBrand is different from what I meant with Mustangs.

 

-----Original Message-----
From: semantic-web-request@w3.org [mailto:semantic-web-request@w3.org] On
Behalf Of sauerkrautragout.13358628@bloglines.com
Sent: Saturday, October 15, 2005 2:07 AM
To: rhm@cdepot.net
Cc: semantic-web@w3c.org
Subject: Re: Mustangs vs myMustang

 

--- Richard H. McCullough" <rhm@cdepot.net wrote:

 

[...]

 

> But the real question is: can a property have two different kinds of
ranges as these declarations do.

 

Yes, but the meaning is not what you are expecting.

 

 

> I'll see if I can validate these statements.

> #       Ford Company   isManufacturerOf   Mustangs

> #       Ford Company   isManufacturerOf   myMustang

> 

> <owl:Property rdf:ID="isManufacturerOf">

>         <rdf:domain rdf:resource="#Company"/>

>         <rdf:range rdf:resource="#CarBrand"/>

>         <rdf:range rdf:resource="#Car"/>

> </owl:Property>

 

"Multiple domains mean that the domain of the property

is the intersection of the identified classes (and similarly for range)."[1]

 

So imho you created a property whose range consists of things that are of

type CarBrand AND of type Car. 

 

[...]

 

> <FordCompany> <isManufacturerOf> <Mustangs/>

> <FordCompany> <isManufacturerOf> <myMustang/>

 

This implies

that both Mustangs and myMustang are of type Car and of type CarBrand. 

 

The easiest solution in this case is propably to specifiy the range of
isManufacturerOf

as some common superclass of both car and carBrand. 

 

[1]: (http://www.w3.org/TR/owl-guide#DefiningProperties)

 

cu

 

valentin

 

http://www.fzi.de/ipe/eng/

http://vzach.blogspot.com