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Re: [sdw] OGC Coordinate Reference System Standards Working Group comments on OWL-Time (#1114)

From: Simon Cox via GitHub <sysbot+gh@w3.org>
Date: Sun, 10 Feb 2019 21:40:40 +0000
To: public-sdwig@w3.org
Message-ID: <issue_comment.created-462176890-1549834839-sysbot+gh@w3.org>
Discussion on this comment has been taking place on email. Here is a copy of the relevant parts of the thread: 

** @dr-shorthair on 2019-02-07** 
Hello Roger – 

Thanks for these suggestions. In particular, thanks for making them very concrete and implementable! 

As mentioned by Scott, any changes to the document has to also respect the W3C process. 
‘Revision’ of a normative document (e.g. a W3C ‘Recommendation’) can only be done through a formal working group and would be a 2-3 year process. 
‘Errata’ can be processed more quickly, by consent of the SDWIG, and with the assistance of the W3C staff contact (Francois Daoust). 

Even though they are tiny and non-normative, your suggestions look more like the former than the latter. 
They are essentially to update the references to the OGC inputs to refer to definitions in a document that had not been published at the time that OWL-Time was prepared. 
Thus, while I see benefits in making the changes you propose, I am not sure I see a path to achieving them. 

Francois – do you see a pathway here? 

**Roger Lott on 2019-02-07**

In that case my view is that OGC should not adopt Time Ontology in OWL (OWL-Time) as an OGC standard, on the grounds that OGC Standards not should be inconsistent with OGC Abstract Specifications.

** @tidoust on 2019-02-08**
Note the word “revision” has a broader meaning for us, encompassing both normative and editorial changes. The IG can easily publish a revision of the Time Ontology that includes editorial errata. What it cannot do is publish a revision of the Time Ontology that includes normative changes.

That said, it may be possible to work around the definitions of “normative” and “editorial” if the changes to incorporate clarify but do not significantly alter the normative essence of the statements. If you believe the proposed updates are useful additions that essentially refine the definitions without notably changing their meaning, I can certainly push internally to have them published as errata.

** @chris-little on 2019-02-07**
 I am not averse to adding some of Roger's suggestions as an informative Annex to the OGC document, providing François can confirm that we could do likewise to the W3C document via a lightweight erratum process.
 
 But I am not enthusiastic. As Simon points out, it would be retro-fitting to a document not published at the time the Ontology was agreed in an open consensus.
 
 I am happy to have an informative annex in an OGC Best Practice for Time highlighting these issues.

** @ogcscotts on 2019-02-08**
I think that a discussion of Roger’s suggestions is a good idea. As we are asking for approval for a document that was created and published before the latest CRS work, it is fine (but not optimal) to be out-of-sync with the current Abstract Spec. If W3C does not have a lightweight erratum or addendum mechanism, seems that we save the edits for the next version of the standard and take you up on your offer to write a companion Best Practice.

** @dr-shorthair on 2019-02-08**
I appreciate that Roger has concerns. Can I just confirm what the main issue is? I think the short version goes like this - 

1. in OWL-Time we refer to "Temporal Coordinate System" - citing ISO 19108:2002 as the source 2. Subsequent work in OGC and ISO has better aligned the definitions of temporal and spatial reference systems, so the designation "Temporal Coordinate Reference System" is now preferred. 
3. There are new documents, not available when OWL-Time was prepared but soon to be part of the OGC baseline, which could be cited to support the view. 

Is the change of name from TCS to TCRS the primary issue? If this is the substantive issue, then I could see the case for an erratum amendment to mention the terminology variation.  

However, since the phrase 'temporal coordinate system' appears in seven places in the document, several of them accompanied by an explicit citation of ISO 19108:2002, cleaning all of these would involve multiple changes as well as introducing reference to one source published later than the cover date. As Roger notes, the OGC and ISO baseline materials available at the time of writing referred to ISO 19108 anyway themselves, so OWL-Time is fully consistent with what was the contemporary baseline. Re-writing body text to make reference to materials that were not available when the document was prepared (and are not yet formally published anyway) would definitely be out of scope for an erratum.

Note also that the internals of temporal reference systems are not addressed in OWL-Time. The primary focus of OWL-Time is interval relations. A brief discussion of temporal reference systems is included primarily to make the case that they are complex and varied, and that the previous assumption that the Gregorian Calendar / 24 hour clock is the only one that matters was not sufficient - see https://www.w3.org/TR/owl-time/#trs-clock-calendar . Beyond that, the treatment of time systems is delegated to more competent authorities. 

** Roger Lott on 2019-02-08**
In my view there are no normative changes in my suggestions.

** @dr-shorthair on 2019-02-08
Agreed. It is terminology/naming not formal semantics. 

There are 7 occurrences of 'temporal coordinate system' in the rec document, and 6 in the rdf document, several of them citing ISO 19108. Some are within normative text, though changing them would have no impact on users. But it would be messy to change them all. 

Are you proposing that adding your note to 4.1.18 would be sufficient to deal with all those mentions? That's probably OK (a 'Note:' is non-normative by definition). I would be less comfortable making changes a new references in a dozen other places.

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Received on Sunday, 10 February 2019 21:40:43 UTC

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