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Re: Semantic E-mail

From: Danny Ayers <danny666@virgilio.it>
Date: Thu, 15 Jul 2004 11:34:16 +0200
Message-ID: <40F64F98.9010908@virgilio.it>
To: Laurian Gridinoc <laurian@gmail.com>
Cc: www-rdf-interest@w3.org, danny@dannyayers.com

Laurian Gridinoc wrote:

>On Thu, 15 Jul 2004 00:34:26 +0200, Danny Ayers <danny666@virgilio.it> wrote:
>  
>
>>Returning to your original example:
>>    
>>
>>><rdf:Property rdf:about="http://NEW/#messageid" rdfs:label="messageId"
>>>rdfs:comment="The unique Message-Id">
>>><rdfs:subPropertyOf rdf:resource="http://purl.org/dc/elements/1.1/identifier"/>
>>>
>>><rdfs:seeAlso rdf:resource="http://xmlns.filsa.org/xmlns.filsa.net/emir/0.2/#messageid"/>
>>><rdfs:seeAlso rdf:resource="http://www.openhealth.org/xmtp#Message-ID"/>
>>><rdfs:seeAlso rdf:resource="URN:ietf:params:rfc822:message-id"/>
>>></rdf:Property>
>>>      
>>>
>>Would I be right in thinking that
>>URN:ietf:params:rfc822:message-id
>>etc. are other ways of describing a message id? To be used as:
>>X hasMessageId Y
>>If so, although owl:equivalentProperty might be an option, I'd be wary of using it because the alternatives might not be /quite/ the same. How about:
>><owl:ObjectProperty rdf:about="http://NEW/#messageid" rdfs:label="messageId"
>>rdfs:comment="The unique Message-Id">
>><rdfs:subPropertyOf rdf:resource="http://purl.org/dc/elements/1.1/identifier"/>
>>
>><rdfs:subPropertyOf rdf:resource="http://xmlns.filsa.org/xmlns.filsa.net/emir/0.2/#messageid"/>
>><rdfs:subPropertyOf rdf:resource="http://www.openhealth.org/xmtp#Message-ID"/>
>><rdfs:subPropertyOf rdf:resource="URN:ietf:params:rfc822:message-id"/>
>></owl:ObjectProperty>
>>
>>In other words, http://NEW/#messageid shares characteristics of each of
>>these, but perhaps not all, is a specialization.
>>    
>>
>
>It is a specialization of dc:identifier, but I don't think it is ok to
>say that an identifier is a specialization of itself (more or less).
>  
>
>And I don't think it's ok to suggest "J sameAs K" using both "J
>subPropertyOf K" and "K subPropertyOf J"
>  
>

I'm not suggesting that - the new property doesn't appear as the object 
of any of the statements. In any case, if it did I believe the 
subsumption rules would result in J owl:equivalent K, which would be 
perfectly ok (but possibly not what you wanted).

If the other terms really are equivalent then you could use 
owl:equivalentProperty, but then why bother creating a new term when you 
could use an equivalent?

>>Again, if I'm reading the intention correctly, this is all working
>>within the property(/class) hierarchy, and should stay comfortably
>>within OWL DL, although I believe you will have to explictly type the
>>referenced properties, i.e. something like:
>>    
>>
> > <owl:ObjectProperty
>rdf:about="http://xmlns.filsa.org/xmlns.filsa.net/emir/0.2/#messageid"
>/>
>
>The intention is promote partial understanding within the vocabulary
>itself; not by using (mixing) volatile elements, but by referring
>several volatile elements, having a degree of redundancy.
>
>I thought that this was ment to be possible with RDF Schema, and from
>my understanding, seeAlso was created for this purpose.
>  
>

If you want to use these elements within the reasoning (to enable 
partial understanding) then you'll have to describe them in terms which 
can be reasoned with. All rdfs:seeAlso provides [1] for use in inference 
about the object is that it is an rdfs:Resource which is, as my 
grandmother use to say, neither use nor ornament.

It depends what specific kind of partial understanding you're after, but 
RDF(S) could certainly provide some in this case. You could stay with 
RDF(S) by substituting rdf:Property for owl:ObjectProperty in the 
listing above, and doing without the explicit typing of the referenced 
terms. But I got the impression from the thread that OWL DL was wanted, 
a would  require being more specific in the description of the terms to 
which you were referring.

The volatility issue is tricky - it's a common problem. OWL has 
versioning capability terms that could be used to manage this, though 
where individual terms may change independently OWL's per-schema 
versioning isn't really granular enough. The craftiest solution I've 
seen to this came recently from Alistair Miles and Chaals, using a 
separate little ontology for each term [2].


Cheers,
Danny.

[1]  http://www.w3.org/TR/rdf-mt/#RDFS_axiomatic_triples
[2] http://esw.w3.org/topic/SchemaChangeWithOwl

> 
>Thank you,
>Laur
>
>
>  
>


-- 

Raw
http://dannyayers.com
Received on Thursday, 15 July 2004 05:37:46 UTC

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