- From: Frans Knibbe | Geodan <frans.knibbe@geodan.nl>
- Date: Wed, 18 Mar 2015 12:30:18 +0100
- To: public-sdw-wg@w3.org, Simon Cox <Simon.Cox@csiro.au>
- Message-ID: <550961CA.2020700@geodan.nl>
On 2015-03-17 21:40, Simon.Cox@csiro.au wrote: > > >>> Firstly, the OGC reference systems do have URIs, but they are not > dereferencable to data describing the 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! > > It has been running fine for about 3 years now. It is unfortunate to > read untested, incorrect assertions made about availability of > resources, and the stability of the services that OGC provides to the > community, particularly on this forum. > It is unfortunate indeed, and I feel very ashamed at the moment. I hindsight, I confused two things: I have looked up OGC URIs before and I noticed they did not return RDF data. Somehow I had remembered this incorrectly, and 'no RDF data' became 'no data'. Two very different things, so I was very sloppy in writing what I did. I see how my carelessness could have reflected badly on the OGC or CSIRO, and I very much regret this. I thank Simon for pointing out the severity of my hasty comments. Please accept my apologies. I for one have learned an important lesson: /do/ perform checks when making factual statements. Greetings, Frans > > *From:*Frans Knibbe | Geodan [mailto:frans.knibbe@geodan.nl] > *Sent:* Wednesday, 18 March 2015 7:13 AM > *To:* public-sdw-wg@w3.org > *Subject:* Re: Working list of BP requirements identified during the > SDW WG f2f > > 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> > > ------------------------------------------------------------------------ > ------------------------------------------------------------------------ Frans Knibbe Geodan President Kennedylaan 1 1079 MB Amsterdam (NL) T +31 (0)20 - 5711 347 E frans.knibbe@geodan.nl www.geodan.nl <http://www.geodan.nl> | disclaimer <http://www.geodan.nl/disclaimer> ------------------------------------------------------------------------
Received on Wednesday, 18 March 2015 11:30:57 UTC