RE: SSN - term-by-term integration is finished

A few issues:


1.     In O&M resultTime is required. Since observation/actuation/sampling is now conceived of as an act or event, then it has a finish (and start time) by definition. I suggest that the cardinality constraint on sosa:resultTime should be ‘exactly 1’. (OWA means that it may be missing in a particular representation, but semantically it is known to exist.)

2.     Similar for phenomenonTime for Observations at least.

3.     Similar for hasResult – each of these acts is pointless without a result – I think we should indicate this with a ‘min 1’ restriction.

4.     Entailment of ‘min 0’ is a little unclear anyway, since that is the default cardinality. If you want to note that a property is associated with a class, better use a constraint like
     sosa:resultTime only xsd:dateTime
e.g.
     sosa:Observation  rdfs:subClassOf [
         a owl:Restriction ;
         owl:allValuesFrom xsd:dateTime ;
         owl:onProperty sosa:resultTime ; ] .

5.     Sampler needs to also be a subclass of

a.     ssn:System

b.     ssn:implements some sosa:Procedure

6.  Only one of these two restrictions on sosa:Procedure should be present:
      ssn:hasOutput only ssn:Output
   ssn:hasOutput some ssn:Output
Which one?

7.  Some combination of the following is required to bring sosa:Sampling into consistency:

a.  sosa:hasResultingSample rdfs:subPropertyOf sosa:hasResult

b.  sosa:hasResultingSample rdfs:range sosa:Sample

c.  sosa:Sample rdfs:subClassOf sosa:Result

8.  I’m generally pretty comfortable with global rdfs:range constraints on properties. Did we decide to not use them at all? It would halve the number of local restrictions/constraints on the classes.

I could implement some of these in a branch, but it all got bollixed up yesterday when I was trying to issue pull-request the same time as you other guys were editing, so you get them in an email today instead.

Simon

From: Maxime Lefrançois [mailto:maxime.lefrancois@emse.fr]
Sent: Saturday, 15 April, 2017 04:59
To: SDW WG Public List <public-sdw-wg@w3.org>
Subject: SSN - term-by-term integration is finished

Dear all,

Term-by-term integration is finalized, and a pull request has been issued:
https://github.com/w3c/sdw/pull/700/


Ontologies in the integrated folder have nearly the same content as the ontologies in the 'rdf' and 'ssn_separated' folders, except for:
 - dc:source which I didn't kept in the integrated folder (but can be added)
 - terms are organized in modules and introduced in the same order as in https://www.w3.org/2015/spatial/wiki/Terms


I have checked programmatically:
 - The syntax of the ontologies
 - There is no more mistake in sosa vs ssn prefixes (there were a few),
 - The ontologies are in OWL DL.

Last step will be to add some local restrictions to formalize the "domainIncludes" and "rangeIncludes" annotations

We can delete rdf/sosa.ttl and ssn_separated/ssn.ttl now, as the documents in the integrated folder are a lot easier to read (terms are introduced as in https://www.w3.org/2015/spatial/wiki/Terms), more consistent in terms of metadata (ssn only), have more ontology metadata, and less unused annotation properties.

Best,
Maxime