- From: Frans (Geodan) <frans.knibbe@geodan.nl>
- Date: Sun, 22 Feb 2015 15:39:13 +0100
- To: Simon.Cox@csiro.au, public-sdw-wg@w3.org
- Message-ID: <54E9EA11.2020107@geodan.nl>
On 2015-02-19 21:47, Simon.Cox@csiro.au wrote: > > Ø… 'Feature': “..equivalent to GFI_Feature defined in ISO 19156:2011”. > Unfortunately GFI_Feature as defined in ISO 19156:2011 is not a web > resource and ISO 19156:2011 is not an open standard (because you have > to pay for it). But it's a start... > > ISO 19156:2011 is jointly published by OGC as Topic 20 of their > Abstract Spec, and available freely here: > http://www.opengeospatial.org/standards/om or directly from > www.opengis.net/doc/om <http://www.opengis.net/doc/om> > Thank you Simon, this document can be valuable input if we want to work on clarifying our basic concepts. The definition of 'feature' in paragraph 4.6 caught my eye. A feature is an 'abstraction of real world phenomena'. Could we say that the OGC feature equals the W3C information resource? Is a collection of data about Greater London a feature and Greater London itself not? Paragraph D.1 seems very useful in shedding light on the basic concepts that we will work with (features, coverages, observations). > (Side question: does payment=”not open”? On that basis almost the > entire academic literature is “closed”, since you can only read it if > you have a subscription! Ditto most books. I agree that the ISO > business model is tedious, and does not meet modern expectations for > web standards, but an argument can easily be made that ISO standards > are indeed “open” as there is no limitation on access to the document > other than buying it, and then there is no limitation on use. ) > Well, in my book payment for a standard means it is not open. But of course opinions can differ. This wikipedia article <http://en.wikipedia.org/wiki/Open_standard> has an overview of some definitions of what constitutes an open standard. In Spanish and Danish law for example, an Open Standard really should be free of charge, so the article says. To me it is just strange to publish a standard that should help the world in getting things done and restrict access to it at the same time. Payment is a barrier that blocks access. For some it is tedious (I think I could get the money but it would take me some bureaucratic effort) but I imagine the payment makes the standard unreachable for others (thinking of a lone web developer in Bangladesh). Besides that, when you do have access to a single standard document in most cases reading it will show that you need some other standards as well (ISO 19156:2011 has twelve references to other ISO standards documents, for example). But I think it is modern OGC policy to publish OGC versions of the ISO 191** standards for free? That is a good thing. Is it easy to translate references to ISO 191** documents to equivalent OGC documents? Greetings, Frans > *From:*Frans (Geodan) [mailto:frans.knibbe@geodan.nl] > *Sent:* Friday, 20 February 2015 12:14 AM > *To:* public-sdw-wg@w3.org > *Subject:* Re: Spatial context > > I think that the question whether data are spatial data largely > depends on the data publisher. The designation “Greater London” could > be published as a text label, in which case it is not spatial data. It > could also be published as a toponym, in which it is spatial data. > > This discussion seems to point at an important requirement for our > work, which may or may not be derived from use cases, but still is > important: We need clear and universal semantics. > > What makes a thing spatial? Does it have to have geometry? Does it > have to have three dimensions? Does it need to be a terrestial object? > Does it need to be non-fictional? All these things are debatable, but > rather than debate them it would be good to have agreed upon semantics. > > At the moment, there are some definitions out there on the semantic > web. For example, the Location Core Vocabulary > <http://www.w3.org/ns/locn> defines the concept 'location'. > Unfortunately the definition is self-referencing: “any location, > irrespective of size or other restriction”. In other words, it is very > open to interpretation. Is “Paris” a location (knowing that there are > multiple locations with that name)? Is Atlantis (fictional) a > location? Is Olympus Mons (on Mars) a location? > > GeoSPARQL <%28http:/www.opengis.net/ont/geosparql> has definitions for > the concept 'SpatialObject': “..everything that can have a spatial > representation” (unfortunately the 'spatial representation' part is > undefined) and 'Feature': “..equivalent to GFI_Feature defined in ISO > 19156:2011”. Unfortunately GFI_Feature as defined in ISO 19156:2011 is > not a web resource and ISO 19156:2011 is not an open standard (because > you have to pay for it). But it's a start... > > Greetings, > Frans > > On 2015-02-19 11:50, Ed Parsons wrote: > > This is a great discussion and I think it is central to the > potentially difficult overlap between the two community perspectives. > > I'm sure Josh will chip in but I do think we need to recognise > that we need to include spatial information for which it is not > possible to define a geometry or have linked to as an attribute - > This I think is what Josh means by context, I am writing this > email from a location within "Central London" although there is > not a canonical geometry that represents the shape of central London. > > This is an example of what Mike Goodchild calls a Platial Problem ! > > This must be in scope, does the current wording around spatial > information accommodate it ? > > Ed > > On Thu Feb 19 2015 at 10:26:55 Andrea Perego > <andrea.perego@jrc.ec.europa.eu > <mailto:andrea.perego@jrc.ec.europa.eu>> wrote: > > Andreas's mail gives me the opportunity to explain the objection I > raised during the call [1] about the proposal of adding "spatial > context" into scope question #1 [2]. > > My main concern is that the use of "spatial context" in the > scoping > question may be confusing, and probably unnecessary. > > In my understanding, spatial context is specified through > spatial data > - i.e., it denotes one of their possible uses. So, "spatial data" > should be inclusive enough - it would cover spatial data as a > whole, > irrespective of their use. > > Thanks! > > Andrea > > ---- > [1]http://www.w3.org/2015/02/18-sdw-minutes.html > [2]http://www.w3.org/2015/spatial/wiki/Scope_questions_and_Requirements > > On Wed, Feb 18, 2015 at 10:10 PM, Andreas Harth <harth@kit.edu > <mailto:harth@kit.edu>> wrote: > > Hi, > > > > the issue I had with the term "spatial context" is that I > did not know > > what the "context" part was supposed to mean. > > > > If I understood Josh correctly, he mentioned that a geometry, > > a place description or a spatial feature should be referenceable > > in data. > > > > If "spatial context" does mean that, I'm fine with the > phrasing of > > the scoping question. > > > > Cheers, > > Andreas. > > > > > > -- > 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. > > > > ------------------------------------------------------------------------ > > <http://www.avast.com/> > > > > Dit e-mailbericht bevat geen virussen en malware omdat avast! > Antivirus <http://www.avast.com/> actief is. > --- Dit e-mailbericht bevat geen virussen en malware omdat avast! Antivirus-bescherming actief is. http://www.avast.com
Received on Sunday, 22 February 2015 14:39:46 UTC