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Re: Linking Systems and Features of Interest

From: Maxime Lefrançois <maxime.lefrancois@emse.fr>
Date: Fri, 28 Apr 2017 17:58:06 +0000
Message-ID: <CALsPASUqz+2gVotDhyHD9n8h0ceNS0b5b6x=Pa05Mxv5BAFVeg@mail.gmail.com>
To: Raúl García Castro <rgarcia@fi.upm.es>, SDW WG Public List <public-sdw-wg@w3.org>
Hi Raul,

I agree that being able to answer:

"what are the sensors that observe that specific feature of interest?"

seems quite important. Before argumenting further,  I'd like to share my
concerns about way you use class ObservableProperty in your examples:

You use instance ns:Occupancy as the observable property of two different
features of interest, yet this is not correct with respect to the
definition of ObservableProperty: "An observable quality (property,
characteristic) of a FeatureOfInterest.".
ssn:Property further adds: "A quality of an entity. An aspect of an entity
that is intrinsic to and cannot exist without the entity."

So ns:Occupancy should either be the quality of ns:RoomX, or ns:BuildingX.
But not both.

We already discussed about "what is an instance of ssn:Property" in March:
- see wiki page section
https://www.w3.org/2015/spatial/wiki/Link_between_FeatureOfInterest_and_xxxProperty#What_is_an_instances_of_ssn:Property_.3F

- and thread starting with this mail:
https://lists.w3.org/Archives/Public/public-sdw-wg/2017Feb/0478.html


So if we accept to conform to the old (and the new) definition, your
examples could be rewritten as follows:

ns:mySensor a sosa:Sensor ;
   sosa:observes ns:RoomXOccupancy .
 ns:RoomXOccupancy a sosa:ObservableProperty ;
   ssn:isPropertyOf ns:RoomX .
 ns:RoomX a sosa:FeatureOfInterest .

ns:anotherSensor a sosa:Sensor ;
   sosa:observes ns:BuildingXOccupancy .
 ns:BuildingXOccupancy a sosa:ObservableProperty ;
   ssn:isPropertyOf ns:BuildingX .
 ns:BuildingX a sosa:FeatureOfInterest .

and it is actually easy to ask: "what are the sensors that observe feature
of interest ns:RoomX ?" as follows:

SELECT ?sensor WHERE {
  ?sensor sosa:observes ?property .
  ?property sosa/ssn:isPropertyOf ns:RoomX .
}

On the other hand:

1. This is true in SSN, but hasProperty/isPropertyOf must be moved to sosa
so that it becomes true in SOSA.
2. Even then, this would only be true for sensors, (because there is no
property parallel to sosa:observes for actuators)


Last point I would like to make is:
During last call, some of the group members were afraid that moving
hasProperty/isPropertyOf to SOSA would require that we also move Property
to SOSA, which would in turn require to use the rdfs:subClassOf axiom.

I think I managed to explain why I think this is not true during the call:

we just move hasProperty/isProperty as follows:

  ssn:hasProperty a owl:ObjectProperty ;
    rdfs:label "has property"@en ;
    skos:definition "Relation between an entity and a Property of that
entity."@en ;
    rdfs:comment "Relation between an entity and a Property of that
entity."@en ;
    owl:inverseOf ssn:isPropertyOf ;
    rdfs:domainIncludes sosa:FeatureOfInterest ;
    rdfs:rangeIncludes sosa:ObservableProperty ;
    rdfs:rangeIncludes sosa:ActuatableProperty ;
    rdfs:isDefinedBy sosa: .

  ssn:isPropertyOf a owl:ObjectProperty ;
    rdfs:label "is property of"@en ;
    skos:definition "Relation between a Property and the entity it belongs
to."@en ;
    rdfs:comment "Relation between a Property and the entity it belongs
to."@en ;
    rdfs:domainIncludes sosa:ObservableProperty ;
    rdfs:domainIncludes sosa:ActuatableProperty ;
    rdfs:rangeIncludes sosa:FeatureOfInterest ;
    owl:inverseOf ssn:hasProperty ;
    rdfs:isDefinedBy ssn: .


and the SSN only contains:

ssn:hasProperty  a owl:InverseFunctionalProperty  ;
    rdfs:isDefinedBy sosa: .

ssn:isPropertyOf  a owl:FunctionalProperty  ;
    rdfs:isDefinedBy sosa: .


Do you believe that could be a sufficiently good proposal ?

Best,
Maxime



Le ven. 28 avr. 2017 à 19:03, Raúl García Castro <rgarcia@fi.upm.es> a
écrit :

> Dear all,
>
> I've been thinking on the issue of moving the ssn:isPropertyOf and
> ssn:hasProperty properties to sosa. I still think that we need something
> more in sosa, but I have realised that those properties are not the
> solution.
>
> The short summary is that I see the need for having in sosa a new
> property that links systems to features.
>
> The long discussion and proposal (with figures) is documented in the wiki:
>
> https://www.w3.org/2015/spatial/wiki/Linking_Systems_and_Features_of_Interest
>
> Kind regards,
>
> --
>
> Dr. Raúl García Castro
> http://www.garcia-castro.com/
>
> Ontology Engineering Group
> Departamento de Inteligencia Artificial
> Escuela Técnica Superior de Ingenieros Informáticos
> Universidad Politécnica de Madrid
> Campus de Montegancedo, s/n - Boadilla del Monte - 28660 Madrid
> Phone: +34 91 336 65 96 <+34%20913%2036%2065%2096> - Fax: +34 91 352 48 19
> <+34%20913%2052%2048%2019>
>
>
Received on Friday, 28 April 2017 17:58:54 UTC

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