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Re: Spatial relations - was RE: Request for help: BP 9 "How to describe relative positions"

From: Jeremy Tandy <jeremy.tandy@gmail.com>
Date: Fri, 02 Sep 2016 06:27:17 +0000
Message-ID: <CADtUq_3uJeeTvP4QtAUTBfa3oVAd0jyy=V4L37LcywDzXY2d9w@mail.gmail.com>
To: Simon.Cox@csiro.au, jlieberman@tumblingwalls.com
Cc: eparsons@google.com, public-sdw-wg@w3.org
Given they're defined in the Owl-time deliverable it would make sense to
add the necessary hooks there for the IANA registry to refer to - per
@phila's email [1].

Next: same discussion for spatial relations!

Jeremy

[1]: http://lists.w3.org/Archives/Public/public-sdw-wg/2016Aug/0234.html
On Fri, 2 Sep 2016 at 02:28, <Simon.Cox@csiro.au> wrote:

> Yes – that would be very helpful.
>
>
>
> *From:* Jeremy Tandy [mailto:jeremy.tandy@gmail.com]
> *Sent:* Friday, 2 September 2016 2:28 AM
> *To:* Cox, Simon (L&W, Clayton) <Simon.Cox@csiro.au>;
> jlieberman@tumblingwalls.com
> *Cc:* eparsons@google.com; public-sdw-wg@w3.org
> *Subject:* Re: Spatial relations - was RE: Request for help: BP 9 "How to
> describe relative positions"
>
>
>
> @simon - that's perfect. Do you agree that it would be a good idea to get
> these registered as Link Relation types on the IANA registry?
>
>
>
> I think the definitions are also in your document [1] for input into the
> registry ...
>
>
>
> Jeremy
>
>
>
> [1]: https://www.w3.org/TR/owl-time/#vocabulary
>
>
>
> On Thu, 1 Sep 2016 at 08:56 <Simon.Cox@csiro.au> wrote:
>
> For temporal relations, I re-drafted a diagram from one of Allen’s papers:
>
> https://www.w3.org/TR/owl-time/images/IntervalRelations.png
>
>
>
> *From:* Jeremy Tandy [mailto:jeremy.tandy@gmail.com]
> *Sent:* Wednesday, 31 August 2016 9:43 PM
> *To:* Joshua Lieberman <jlieberman@tumblingwalls.com>; Cox, Simon (L&W,
> Clayton) <Simon.Cox@csiro.au>
> *Cc:* eparsons@google.com; public-sdw-wg@w3.org
> *Subject:* Re: Request for help: BP 9 "How to describe relative positions"
>
>
>
> *[…]*
> Finally, I also note that I still need help on the "spatial relations"
> topic that was second in my original email. More help required please.
>
>
> Jeremy
>
>
>
> *[…]*
>
> On Wed, 31 Aug 2016 at 10:26 Jeremy Tandy <jeremy.tandy@gmail.com> wrote:
>
> Hi-
>
>
>
> BP doc section § 10.5.1 "Describing location" [1] is where we intend to
> provide all the guidance that explains how you should encode location
> information in a web-friendly way.
>
>
>
> This includes BP 8 "Provide geometries on the Web in a usable way" [2] and
> BP 9 "How to describe relative positions" [3].
>
>
>
> (I think it's likely that we will also need a BP to help people choose the
> right CRS too ...)
>
>
>
> We editors envisage BP 9 covering:
>
>
>
> (1) Linear referencing
>
> (2) Use of spatial relations [4]
>
>
>
> ...
>
>
>
> *[…]*
>
>
>
> (2)
>
> We also want to demonstrate how spatial relations are used. There are
> obvious examples of topological relationships such as "this administrative
> unit _touches_ that administrative unit" (or contains etc.).
>
>
>
> I recall that we were going to get the set of topological relationships
> added to the IANA Link Relations registry [7]. I am not even sure which set
> of topological relations we should be recommending? GeoSPARQL has me
> somewhat confused with "Simple Features Relation", "Egenhofer Relation" and
> "RCC8 Relation". Then there's D9-EIM too ...
>
>
>
> Can someone provide me some worked examples using the preferred set of
> topological relationships?
>
>
>
> We also need to illustrate use of _directional_ (e.g. "left", "in front
> of" and "astern") and _distance_ relations (e.g. "at", "nearby" and "far
> away"). I don't know of any formalised vocabulary for expressing these
> things. If there is one, should we be seeking to add these to the IANA Link
> Relations registry too?
>
>
>
> Again, worked examples requested! If you can related them to an urban
> environment / flooding scenario all the better. (e.g. someone might assert
> "the flooding is near my house")
>
>
>
> Finally, we also need to show people how to express "fuzzy" spatial
> things. Examples we have elsewhere in the BP doc are "the American West"
> and "Renaissance Italy". These are spatial things were there is not general
> agreement about the exact geographic extent, so it is not possible to use a
> geometry to describe it. What is the best way to describe things like this?
> Should we use spatial relations e.g. "downtown" _contains_ city districts
> A, C, D, and G (because "everyone" agrees this) - but we're not saying it's
> exact geometry because it's a colloquial term used by citizens of our
> fictional Nieuwhaven.
>
>
>
> Again, I'd like to see a worked example.
>
>
>
> ...
>
>
>
> There's a lot of questions wrapped up in this email. I'm looking for help
> to resolve them ... preferably with someone in the WG taking the lead to
> coordinate a response.
>
>
>
> I'm also aware that we need to avoid an RDF bias, so it would be good to
> have examples in other formats too.
>
>
>
> Volunteers, please step forward!
>
>
>
> Thanks in advance. Jeremy
>
>
>
> [1]: http://w3c.github.io/sdw/bp/#bp-expr-geo
>
> [2]: http://w3c.github.io/sdw/bp/#describe-geometry
>
> [3]: http://w3c.github.io/sdw/bp/#relative-position
>
> [4]: http://w3c.github.io/sdw/bp/#spatial-relations
>
> [5]: https://github.com/ISO-TC211/HMMG
>
> [6]:
> http://inspire.ec.europa.eu/documents/Data_Specifications/INSPIRE_DataSpecification_TN_v3.2.pdf
>
>
> [7]: http://www.iana.org/assignments/link-relations/link-relations.xhtml
>
>
> --
>
> *Ed Parsons *FRGS
> Geospatial Technologist, Google
>
> Google Voice +44 (0)20 7881 4501
> www.edparsons.com @edparsons
>
>
Received on Friday, 2 September 2016 06:28:29 UTC

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