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Re: ACTION-251: (ISSUE-88) write up how an ssn:platform and a sosa:platform are essentially the same, with an example (Spatial Data on the Web Working Group)

From: Krzysztof Janowicz <janowicz@ucsb.edu>
Date: Tue, 24 Jan 2017 10:19:51 -0800
To: Joshua Lieberman <jlieberman@tumblingwalls.com>, Raphaël Troncy <raphael.troncy@eurecom.fr>
Cc: Kerry Taylor <kerry.taylor@anu.edu.au>, Rob Atkinson <rob@metalinkage.com.au>, Raúl García Castro <rgarcia@fi.upm.es>, "public-sdw-wg@w3.org" <public-sdw-wg@w3.org>, "Cox, Simon (CESRE, Kensington)" <Simon.Cox@csiro.au>, Armin Haller <armin.haller@anu.edu.au>
Message-ID: <4e7bea43-9f08-4161-46cf-7a89c5b46bc5@ucsb.edu>
Hi Josh,

yes, exactly.  Due to the order of imports in our draft and the design 
goals of the lightweight SOSA, we have two possible approaches that we 
can take and have to decide by case: (i) if a SOSA class and an SSN 
class point to the same (in the OWL equivalentClass sense) concept then 
we can either simply use the SOSA class in SSN as SSN imports SOSA or we 
have an equivalentClass between both (this is why OWL has an 
equivalentClass predicate); or (ii) we can decide that the SSN class 
adds additional axioms (and this will typically be the case) and thus 
define the SSN class to be a subclass of the SOSA class. Btw, this is 
not all that new but done by ontologies over and over again and also the 
technical foundation of ontology alignment.

Best,
Jano

On 01/24/2017 10:03 AM, Joshua Lieberman wrote:
> If I understand correctly, the effect of introducing additional axioms in SSN is to make ssn:some_class members a subset, and therefore the class a subclass of sosa:some_class. So the subclass relationship should express clearly the relationship between the two concepts. If it is true that no additional axiomatization is being applied in ssn, then reusing the sosa:some_class in ssn also makes sense, but that will be rare I should think.
>
> It certainly has not been clear up until now, though, what the best rdf/owl engineering practice should be to realize this sort of modularization, so clear, well documented examples and explanations would really help establish the options.
>
> —Josh
>
>> On Jan 24, 2017, at 12:54 PM, Raphaël Troncy <raphael.troncy@eurecom.fr> wrote
>> Hi Krzysztof,
>>
>> You're arguing about any sosa/ssn classes in general while I'm discussing specific classes on which there seem to be an agreement to get rid of most of the axioms. I don't see why sosa could not re-use specific ssn classes on which there is little or no axiomatization, and even worse, define a new class with exactly the same annotation properties ... this is the fastest road to confuse developers.
>>
>>   Raphaël
>>
>> -- 
>> Raphaël Troncy
>> EURECOM, Campus SophiaTech
>> Data Science Department
>> 450 route des Chappes, 06410 Biot, France.
>> e-mail: raphael.troncy@eurecom.fr & raphael.troncy@gmail.com
>> Tel: +33 (0)4 - 9300 8242
>> Fax: +33 (0)4 - 9000 8200
>> Web: http://www.eurecom.fr/~troncy/
>>
>>


-- 
Krzysztof Janowicz

Geography Department, University of California, Santa Barbara
4830 Ellison Hall, Santa Barbara, CA 93106-4060

Email: jano@geog.ucsb.edu
Webpage: http://geog.ucsb.edu/~jano/
Semantic Web Journal: http://www.semantic-web-journal.net
Received on Tuesday, 24 January 2017 18:20:28 UTC

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