W3C home > Mailing lists > Public > semantic-web@w3.org > October 2005

RE: Mustangs vs myMustang

From: Hans Teijgeler <hans.teijgeler@quicknet.nl>
Date: Thu, 20 Oct 2005 08:34:25 +0200
Message-Id: <200510200634.j9K6YQ0Y010729@vmx40.multikabel.net>
To: <jos.deroo@agfa.com>
Cc: "'West, Matthew'" <matthew.west@shell.com>, "'Paap, Onno'" <onno.paap@ezzysurf.com>, <semantic-web@w3c.org>, <semantic-web-request@w3.org>
Hi Jos,

 

As far as your point 2. is concerned please read my response to Dick
McCullough.

 

With all due respect (said the newbee to the guru) I have doubts about your
piece of RDF/XML code. It may be syntactically correct (which I cannot
judge), but to me it is as clear as the London fog.

 

In the RDF Primer I read: 

An rdf:parseType="Resource" attribute is used to indicate that the contents
of an element are to be interpreted as the description of a new (blank node)
resource, without actually having to write a nested rdf:Description element.

 

Your code does use rdf:Description despite that, and seems to describe a
blank node resource for rdf:type, where I would have expected that you
wanted to say something about the Property isManufacturerOf. Yet I may be
totally wrong and confused, but RDF and OWL aren't as easy to understand as
claimed by some.

 

All that leaves me with the uncertainty about the question whether my code
(below) is correct or not.

 

Please enlighten me.

Hans

 

================================================

 

-----Original Message-----
From: semantic-web-request@w3.org [mailto:semantic-web-request@w3.org] On
Behalf Of jos.deroo@agfa.com
Sent: Wednesday, October 19, 2005 10:31 PM
To: hans.teijgeler@quicknet.nl
Cc: West, Matthew; 'Paap, Onno'; semantic-web@w3c.org;
semantic-web-request@w3.org
Subject: RE: Mustangs vs myMustang

 

 

Hi, Hans

 

1/ For following piece of N3

 

@prefix owl: <http://www.w3.org/2002/07/owl#>.

@prefix : <http://www.example.org/library#>.

 

:FordCompany a [a owl:Restriction;

                 owl:onProperty :isManufacturerOf;

                 owl:someValuesFrom :Mustangs].

 

you have following piece of RDF/XML

 

<rdf:RDF xmlns="http://www.w3.org/2002/07/owl#"

    xmlns:owl="http://www.w3.org/2002/07/owl#"

    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">

 

    <rdf:Description rdf:about="http://www.example.org/library#FordCompany">

        <rdf:type rdf:parseType="Resource">

            <rdf:type
rdf:resource="http://www.w3.org/2002/07/owl#Restriction"/>

            <onProperty
rdf:resource="http://www.example.org/library#isManufacturerOf"/>

            <someValuesFrom
rdf:resource="http://www.example.org/library#Mustangs"/>

        </rdf:type>

    </rdf:Description>

</rdf:RDF>

 

2/ am actually not clear about your singleton class idea..

 

 

-- 

Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/

 

=====================================================

 

"Hans Teijgeler" <hans.teijgeler@quicknet.nl>

Sent by: semantic-web-request@w3.org

18/10/2005 11:22

 

 

        To:     Jos De_Roo/AMDUS/MOR/Agfa-NV/BE/BAYER@AGFA

        cc:     "'Paap, Onno'" <onno.paap@ezzysurf.com>,
<semantic-web@w3c.org>, "West, 

Matthew" <matthew.west@shell.com>

        Subject:        RE: Mustangs vs myMustang

 

Hi Jos and Geoff,

 

Forgive me my ignorance, but could you please translate:

 

:FordCompany rdf:type [a owl:Restriction;

                 owl:onProperty :isManufacturerOf;

                 owl:someValuesFrom :Mustangs].

 

into RDF/XML? As a newcomer RDF/XML is clearer to me than the above code 

(I am not one of the seemingly many RDF/XML bashers, probably because it was

the first I learned to use).

 

Not to seem lazy, I'll give it a try myself:

I first define the class:

 

    <owl:Class rdf:ID="MustangManufacturer">

        <rdfs:subClassOf rdf:resource="#CarManufacturer"/>

        <owl:Restriction> 

            <owl:onProperty rdf:resource="#isManufacturerOf" /> 

            <owl:someValuesFrom rdf:resource="#Mustang" /> 

        </owl:Restriction>

    </owl:Class>

 

and then the individual Ford Company that is typed with above anonymous

class:

 

   <owl:Thing rdf:ID="FordCompany"/> 

    <owl:Thing rdf:about="#FordCompany">

        <rdf:type rdf:resource="#MustangManufacturer"/> 

    </owl:Thing>

 

QUESTIONS:

1. is this code correct?

2. Could I, instead of the class MustangManufacturer also define a 

singleton

class FordCompany? (that wouldn't help in this case, because it is 

possible

that other companies manufacture Mustangs in licence). The advantage,

however, of defining that singleton would be that I can define everything

about FordCompany at OWL-level, and where necessary cross over to RDF 

later.

That singleton, if defined at some central server, could avoid using

hundreds of URIs for the same company (we call that a "reference

individual", also defined for geographical objects (e.g. London,UK) )

3. How do you define that a class is a singleton? 

 

Regards,

Hans

 

==================================================

 

-----Original Message-----

From: semantic-web-request@w3.org [mailto:semantic-web-request@w3.org] On

Behalf Of jos.deroo@agfa.com

Sent: Tuesday, October 18, 2005 2:36 AM

To: hans.teijgeler@quicknet.nl

Cc: 'Paap, Onno'; semantic-web@w3c.org

Subject: RE: Mustangs vs myMustang

 

 

There is nothing alarming about making a distinction between the thing and

its extension and allowing things to belong to (even their own) extension.

I really like that very much; still for your case my take would be

 

:isManufacturerOf rdfs:domain :Manufacturer; rdfs:range 

:ManufacturedGoods.

 

plus

 

:Mustangs rdfs:subClassOf :ManufacturedGoods.

:myMustang rdf:type :Mustangs.

:FordCompany :isManufacturerOf :myMustang.

 

and have Geoff's

 

:FordCompany rdf:type [a owl:Restriction;

                 owl:onProperty :isManufacturerOf;

                 owl:someValuesFrom :Mustangs].

 

 

-- 

Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/

 

 

 ===================================================

 

"Hans Teijgeler" <hans.teijgeler@quicknet.nl>

17/10/2005 07:59

 

 

        To:     Jos De_Roo/AMDUS/MOR/Agfa-NV/BE/BAYER@AGFA

        cc:     "'Paap, Onno'" <onno.paap@ezzysurf.com>,

<semantic-web@w3c.org>, 

<semantic-web-request@w3.org>

        Subject:        RE: Mustangs vs myMustang

 

 

Hi Jos,

 

Thanks!

 

Your last sentence: " That is indeed *possible* in RDF and OWL Full"  is

rather alarming to me as being seen by you as substandard. 

 

If this were to comply with the constraints of OWL DL, how should I model

it? (your assumption about the base URI was correct).

 

Regards,

Hans

 

============================================================

 

-----Original Message-----

From: jos.deroo@agfa.com [mailto:jos.deroo@agfa.com] 

Sent: Sunday, October 16, 2005 2:32 PM

To: hans.teijgeler@quicknet.nl

Cc: 'Hans Teijgeler'; 'Sullivan, Jan'; 'West, Matthew R SIPC-OFD/321'; 

Paap,

Onno; semantic-web@w3c.org; semantic-web-request@w3.org

Subject: RE: Mustangs vs myMustang

 

> From the beginning I have struggled with chapter 3.1.3 of the OWL Guide. 

 

 

So let me ask this question: If I have:

> 

>    <owl:Thing rdf:ID="Mustang"/> 

>    <owl:Thing rdf:about="#Mustang">

>        <rdf:type rdf:resource="http://www.example.org/library#Mustang"/> 

>    </owl:Thing>

> 

> then does this mean that I have here the class extension?

 

What is the base URI for that rdf:ID="Mustang"?

If it is http://www.example.org/library#

then

 

<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"

          xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"

          xmlns:owl="http://www.w3.org/2002/07/owl#"

          xml:base="http://www.example.org/library#">

 

    <owl:Thing rdf:ID="Mustang"/> 

    <owl:Thing rdf:about="#Mustang">

        <rdf:type rdf:resource="http://www.example.org/library#Mustang"/> 

    </owl:Thing>

 

</rdf:RDF>

 

 

is saying that

 

:Mustang rdf:type :Mustang.

 

or saying that :Mustang is in it's own extension

(and :myMustang is also in that extension)

That is indeed *possible* in RDF and OWL Full

 

 

 

-- 

Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/

 

 

 

 

 

 

 

 

 

 
Received on Thursday, 20 October 2005 06:34:52 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 19:47:06 UTC