RE: BP editors draft ready for review

As to point "c", I think the focus on DCAT is correct.  DCAT is not a another domain standard like ISO 19115. Rather it offers an "exoskeleton" that wraps around domain standards like 19115, MARC, SDMX and other domain metadata standards to support common query capability without altering the original domain specific format.  Thus it aids interoperability while preserving the added domain specific metadata that these standards are designed to capture and preserve.  That sounds like a sensible best practice to me.  Schema.org is not really up to preforming this task well IMHO.

Cheers,
Byron
________________________________________
From: Clemens Portele [portele@interactive-instruments.de]
Sent: Friday, December 16, 2016 12:38 AM
To: Linda van den Brink; public-sdw-wg@w3.org
Subject: Re: BP editors draft ready for review

Dear all,

on my way to London I have been reading the new draft. Good work!

I have made some edits in a branch (that I will publish later) and list some comments for discussion (in London or in 2017) below. I can add GitHub issues, if this is preferred.

a - General: The scope states "this document provides advice on: the choice of ontology and data format to be used when encoding spatial data; …". Since many application schemas exist that use types defined by the ISO 19100 standards and GML data compliant to these application schemas are made accessible in SDIs, what would be the advice regarding mapping the types in the ISO schemas to other representations, in particular RDF and JSON? For RDF probably the work on the ontologies (sensors, time, coverages) will help, but should we provide more explicit guidance somewhere to be consistent with the scope? 13.5 is not complete at the moment.

b - BP1: Chapter 9 states as the first reason why SDIs are not enough that the SDI catalog services are insufficient for the general web (which I agree with). But then the first (!) BP is to provide metadata in the dataset metadata in these catalog services (or similar services for DCAT). Seems a bit inconsistent to me.

c - BP1: The approach to implementation is heavy on DCAT, but does not mention, for example, schema.org<http://schema.org> or other ways to represent such metadata. Isn’t DCAT mainly the ontology used by a certain community just like ISO 19115 is the ontology typically used by the geo-community?

d - BP2: It would help, if there would be more specific advice how to represent the UoM of a quantity value. Will the SOSA work provide this for RDF representations?

e - BP3: As axis order has been and is a common issue, maybe mention it somewhere and include a reference to the OGC Axis Order policy?

f - BP4: I could add ldproxy.net<http://ldproxy.net> as another example and address issue 447 based on our experiences.

g - BP4: Currently this is mainly about the spatial things, but the dataset metadata should also be indexed.

h - BP4: Sitemaps only work for small datasets.

i - BP7: The paragraphs in "Possible Approach to Implementation" are confusing. First the reuse of authoritative identifiers is promoted in the first paragraph and then it is explained why this is in general not a good idea. Why not mainly promote the "mint your own URI and reference the other source" approach and maybe mention the reuse for special cases where it makes sense (whatever these are)?

j - 13.5: Why only list RDF vocabs in the note not also other vocabs like 19107, WKT, GML, GeoJSON, etc?

k - BP8: Referring to "WGS 84" as a CRS is a bit dangerous. Many CRSs in the EPSG register either have "WGS 84" as name or as part of the name. Maybe clarify up-front that in the document, when talking about "WGS 84" as a CRS, it actually means http://www.opengis.net/def/crs/EPSG/0/4326 (or which other variant, lat/long/height, long/lat, x/y/z, etc).

l - BP10: The "Possible Approach to Implementation" is very RDF oriented (see comment j above).

m - BP13: "protocol independent"? HTTP is a protocol, too!

Best regards,
Clemens


On 13 Dec 2016, at 21:09, Linda van den Brink <L.vandenBrink@geonovum.nl<mailto:L.vandenBrink@geonovum.nl>> wrote:

Hi all,

The BP editors draft[1] is ready to be reviewed. As you know we've planned a vote to release a new WD, this Friday.

You should re-read BP4, 6, 7 and 11. These have been significantly updated.

Minor changes include the addition to section 9 of a list of most important BPs when starting from an existing SDI, change of a few BP titles to include the word spatial

For all changes since the last WD see [2] (changes after October are new).

[1]: http://w3c.github.io/sdw/bp/

[2]: https://github.com/w3c/sdw/commits/gh-pages/bp

Linda



This message contains information, which may be in confidence and may be subject to legal privilege. If you are not the intended recipient, you must not peruse, use, disseminate, distribute or copy this message. If you have received this message in error, please notify us immediately (Phone 0800 665 463 or info@linz.govt.nz) and destroy the original message. LINZ accepts no responsibility for changes to this email, or for any attachments, after its transmission from LINZ. Thank You.

Received on Friday, 16 December 2016 01:39:26 UTC