- From: Jeremy Tandy <jeremy.tandy@gmail.com>
- Date: Thu, 01 Sep 2016 16:28:11 +0000
- To: Simon.Cox@csiro.au, jlieberman@tumblingwalls.com
- Cc: eparsons@google.com, public-sdw-wg@w3.org
- Message-ID: <CADtUq_3Db7BKnLy_SsVi0v8T37Bo-tdSWp0AysQd3eCtJSiyRA@mail.gmail.com>
@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 Thursday, 1 September 2016 16:28:55 UTC