- From: Frans Knibbe | Geodan <frans.knibbe@geodan.nl>
- Date: Tue, 17 Mar 2015 21:12:34 +0100
- To: public-sdw-wg@w3.org
- Message-ID: <55088AB2.9070305@geodan.nl>
On 2015-03-17 14:49, Joshua Lieberman wrote: > >> >> >> But more importantly, I think we will have to decide not to view a >> requirement like 'there should be a best practice for minting URIs of >> spatial phenomena' as something we should busy ourselves with. I can >> think of no reason to see the URI minting problem as something that >> is inherently spatial, temporal or spatiotemporal. Besides that, >> there already are some good guidelines on minting URIs out there. > > It isn’t necessarily a critical for a useful URI, but space-time is a > domain and that suggests some value in organizing the URI’s that > explicitly reference features in it. Otherwise multiple unrelated > URI’s are created that resolve to the same location or feature with > resultant overhead to assert their relationships. This is especially > related to the use case for authoritative framework data. I am not sure I understand what you mean. Could you please give an example (real or imaginary)? > >> >>> 1.8 The OGC URI scheme includes common CRS. Tryhttp://www.opengis.net/def/crs/EPSG/0/4326 for example. I trust that one of the OGC people in the meeting mentioned this? >> >> I am fairly sure that this was mentioned, and if not it is good to >> see it mentioned here. Two things came up that indicate that we might >> want to go a step further: Firstly, the OGC reference systems do have >> URIs, but they are not dereferencable to data describing the >> reference systems. Secondly, it would be good to have some best >> practice for the description of reference systems in general, not >> just earth-based reference systems. > > Did you try clicking on the link above? It goes to an (XML) document > defining the CRS. No, I did not click the link. Sorry. But I did now. If I recall correctly, a while ago the link did not return data. But now it does. It is good to see this kind of progress! > >> >> I noticed an interesting parallel for time and space there: In both >> cases the regular reference systems are fairly well covered by >> standards (earth based reference systems for space, Gregorian >> calendar for time), but less common reference systems are not easy to >> use in a standardized way. > > Generally the “less common” ones are complicated because they cover a > wide range of complicated situations, such as the SEDRIS SRM ( > > ISO/IEC 18026:2006). They are standardized, but used mostly when they > can’t be avoided. > There are reference systems that are simple (such as 2D cartesian), but are uncommon because of an uncommon (unique) point of origin. For example, I could state that I see a White-rumped sandpiper at ten o'clock (in which case my present position and orientation is the origin). Or I could say that Ed's keys are in his bedroom. Also a Building Information Model (BIM) could have simple but unique reference system because it has its own point of origin (the corner of a particular land parcel for example). I think that in the domain of time similar (simple but in some way unique) reference systems can be used. I understand that it is a common practice to date archaeological finds in Egypt using the list of kings. That list by itself is simple, it is a list of king names (the related Gregorian dates could change as scientific knowledge progresses). But a find somewhere in the middle east could be dated by another king list (Sumerian kings, Assyrian kings,....). Greetings, Frans > >> >> Regards, >> Frans >> >>> Simon >>> >>> -----Original Message----- >>> From: Andrea Perego [mailto:andrea.perego@jrc.ec.europa.eu] >>> Sent: Monday, 16 March 2015 5:03 PM >>> To: SDW WG >>> Subject: Working list of BP requirements identified during the SDW WG f2f >>> >>> Dear all, >>> >>> I've extracted from the minutes of the BP deliverable group a preliminary list of requirements, concerning the discussed use cases (1-24). >>> >>> You can find it on the wiki: >>> >>> https://www.w3.org/2015/spatial/wiki/BP_Requirements >>> >>> Please have a look, and modify / extend it as you see fit. >>> >>> Cheers, >>> >>> Andrea >>> >>> -- >>> Andrea Perego, Ph.D. >>> Scientific / Technical Project Officer >>> European Commission DG JRC >>> Institute for Environment & Sustainability Unit H06 - Digital Earth & Reference Data Via E. Fermi, 2749 - TP 262 >>> 21027 Ispra VA, Italy >>> >>> https://ec.europa.eu/jrc/ >>> >>> ---- >>> The views expressed are purely those of the writer and may not in any circumstances be regarded as stating an official position of the European Commission. >>> >>> >> >> >> ------------------------------------------------------------------------ >> Frans Knibbe >> Geodan >> President Kennedylaan 1 >> 1079 MB Amsterdam (NL) >> >> T +31 (0)20 - 5711 347 >> E frans.knibbe@geodan.nl <mailto:frans.knibbe@geodan.nl> >> www.geodan.nl <http://www.geodan.nl/> | disclaimer >> <http://www.geodan.nl/disclaimer> >> ------------------------------------------------------------------------ >
Received on Tuesday, 17 March 2015 20:13:10 UTC