Re: Agenda for Best Practice sub-group, 14:00UTC 1-June-2016

Many thanks for clarifying this point, Matt!

Andrea

On 08/06/2016 19:21, matthew perry wrote:
> Hi Andrea,
>
> In GeoSPARQL, :SpatialObject was more of an abstract class that served
> as the domain and range for topological relations. I don't think we
> considered :SpatialObjects that were neither :Features nor :Geometries.
>
> Thanks,
> Matt
>
>
> On 6/8/2016 5:56 AM, Andrea Perego wrote:
>> On 01/06/2016 14:43, matthew perry wrote:
>>> Hi everyone,
>>>
>>> The Feature subClassOf SpatialObject does seem a bit awkward in
>>> retrospect. The main idea was that for qualitative spatial reasoning, we
>>> don't need quantitative geometries. It should be possible to express
>>> topological relations between features directly (e.g., New York inside
>>> United States), so we defined SpatialObject as the class of things that
>>> can have topological relations, and Feature and Geometry are disjoint
>>> subClasses of SpatialObject.
>>
>> Thanks, Matt.
>>
>> Coming back to the comparison with ISO, does this mean then that, in
>> GeoSPARQL, :SpatialObject subsumes also the notion of "real-world
>> phaenomena", and not only features (GFI_Feature) and geometries
>> (GM_Object)?
>>
>> Andrea
>>
>>
>>> Thanks,
>>> Matt
>>>
>>>
>>> On 6/1/2016 4:58 AM, Clemens Portele wrote:
>>>> Hm, yes, good question. I did not remember that we made geo:Feature a
>>>> geo:SpatialObject in the GeoSPARQL development. I agree with you, from
>>>> the definitions this seems wrong. Perhaps that could be rediscussed,
>>>> if there is a GeoSPARQL revision.
>>>>
>>>> Clemens
>>>>
>>>> On 1. Juni 2016 at 10:38:24, Andrea Perego
>>>> (<mailto:andrea.perego@jrc.ec.europa.eu>andrea.perego@jrc.ec.europa.eu)
>>>> wrote:
>>>>
>>>>> Hi, Clemens.
>>>>>
>>>>> On 01/06/2016 8:26, Clemens Portele wrote:
>>>>> > If we use 19107 as the basis, a TP_Object is a SpatialObject, too.
>>>>> >
>>>>> > This is the definition of "topological object" (the TP_Object):
>>>>> > "spatial object representing spatial characteristics that are
>>>>> invariant
>>>>> > under continuous transformations".
>>>>> >
>>>>> > The definition of "geometric object" (the GM_Object) is: "spatial
>>>>> object
>>>>> > representing a geometric set" where geometric set is "a set of
>>>>> points".
>>>>> >
>>>>> > GeoSPARQL is consistent with this, geo:Geometry is a sub-class of
>>>>> > geo:SpatialObject. If we would define xyz:Topology it should be a
>>>>> > sub-class of geoSpatialObject, too.
>>>>>
>>>>> What is unclear to me is why, in GeoSPARQL, feature is made a subclass
>>>>> of spatial object.
>>>>>
>>>>> Putting together the relevant ISO definitions:
>>>>> - feature: "abstraction of real-world phenomena" (ISO 19101, 19107,
>>>>> 19109, 19156)
>>>>> - spatial object: "object used for representing a spatial
>>>>> characteristic
>>>>> of a feature" (ISO 19107)
>>>>> - geometry (geometric object): "spatial object representing a
>>>>> geometric
>>>>> set" (ISO 19107)
>>>>>
>>>>> Based on them, a feature is not a spatial object - or I'm missing
>>>>> something?
>>>>>
>>>>> Andrea
>>>>>
>>>>>
>>>>> > Clemens
>>>>> >
>>>>> >
>>>>> > On 1. Juni 2016 at 03:37:53, Joshua Lieberman
>>>>> > (jlieberman@tumblingwalls.com
>>>>> <mailto:jlieberman@tumblingwalls.com>) wrote:
>>>>> >
>>>>> >> Yes, a GM_object instance is generally a geometry, but there can be
>>>>> >> other spatial objects such as linear references, addresses,
>>>>> >> placenames, etc. I’m pondering now whether TP_Object should also
>>>>> be a
>>>>> >> subclass of SpatialObject, but I think it too is a form of spatial
>>>>> model.
>>>>> >>
>>>>> >> “Object” is vague, but possibly less confusing than “model” or
>>>>> >> “representation”. The confusion may be a fundamental property of
>>>>> the
>>>>> >> GFM, because one first models the worlds as features, then
>>>>> models the
>>>>> >> features in turn as spatial objects. Making both feature and
>>>>> geometry
>>>>> >> disjoint subclasses of spatial object in GeoSPARQL means, I think,
>>>>> >> that SpatialObject really can’t mean anything except a step of
>>>>> removal
>>>>> >> from owl:Thing.
>>>>> >>
>>>>> >> Josh
>>>>> >>
>>>>> >>> On May 31, 2016, at 9:11 PM, Rob Atkinson <rob@metalinkage.com.au
>>>>> >>> <mailto:rob@metalinkage.com.au>> wrote:
>>>>> >>>
>>>>> >>> it all depends what you mean :-)
>>>>> >>>
>>>>> >>> I though a GM_object was specifically a geometry. As such it is
>>>>> >>> independent of any real world thing - but it can be used as a
>>>>> >>> property of a real world thing to define a spatial characteristic.
>>>>> >>>
>>>>> >>> as such I would say GM_Object and (real world thing) are disjoint.
>>>>> >>>
>>>>> >>> What I dont really understand is what a Spatial Object is,
>>>>> except it
>>>>> >>> seems to declare that Egenhofer and other spatial operations
>>>>> can be
>>>>> >>> supported on either GM_Object or GF_Feature.{geomproperty}. One
>>>>> >>> wonders if a more elegant way of declaring this was possible
>>>>> without
>>>>> >>> introducing a very strange abstract notion (and the confusion
>>>>> here I
>>>>> >>> think is the evidence for the strangeness)
>>>>> >>>
>>>>> >>> OTOH running with the geoSPARQL as-is makes sense unless its
>>>>> provably
>>>>> >>> broken in terms of the inferences it allows, so I'll just get
>>>>> over my
>>>>> >>> distaste of incompatible naming vs. intent.
>>>>> >>>
>>>>> >>> Rob
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>> On Wed, 1 Jun 2016 at 09:58 Joshua Lieberman
>>>>> >>> <jlieberman@tumblingwalls.com
>>>>> <mailto:jlieberman@tumblingwalls.com>>
>>>>> >>> wrote:
>>>>> >>>
>>>>> >>> I’m questioning whether that is a good idea.
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>>> On May 31, 2016, at 7:43 PM, simon.cox@csiro.au
>>>>> >>>> <mailto:simon.cox@csiro.au> wrote:
>>>>> >>>>
>>>>> >>>> In GeoSPARQL SpatialObject is superclass of geometry and spatial
>>>>> >>>> feature.
>>>>> >>>>
>>>>> >>>> -----Original Message-----
>>>>> >>>> From: Joshua Lieberman [mailto:jlieberman@tumblingwalls.com]
>>>>> >>>> Sent: Wednesday, 1 June 2016 9:39 AM
>>>>> >>>> To: Cox, Simon (L&W, Clayton) <Simon.Cox@csiro.au
>>>>> >>>> <mailto:Simon.Cox@csiro.au>>
>>>>> >>>> Cc: andrea.perego@jrc.ec.europa.eu
>>>>> >>>> <mailto:andrea.perego@jrc.ec.europa.eu>;
>>>>> >>>> l.vandenbrink@geonovum.nl <mailto:l.vandenbrink@geonovum.nl>;
>>>>> >>>> frans.knibbe@geodan.nl <mailto:frans.knibbe@geodan.nl>;
>>>>> >>>> public-sdw-wg@w3.org <mailto:public-sdw-wg@w3.org>
>>>>> >>>> Subject: Re: Agenda for Best Practice sub-group, 14:00UTC
>>>>> >>>> 1-June-2016
>>>>> >>>>
>>>>> >>>> Can't SpatialObject be disjoint from GF_Feature? Maybe it's
>>>>> >>>> really SpatialRepresentation. Unless we want to call it
>>>>> >>>> TransfinitePointSet.
>>>>> >>>>
>>>>> >>>>> On May 31, 2016, at 6:20 PM, simon.cox@csiro.au
>>>>> >>>>> <mailto:simon.cox@csiro.au> wrote:
>>>>> >>>>>
>>>>> >>>>> That preserves the 'thing is not a subclass of geometry' axiom,
>>>>> >>>>> but misses 'geometry is not a subclass of real-world-thing'.
>>>>> >>>>> I don't see how to do that without a subclass of owl:Thing
>>>>> >>>>> which is disjoint from GM_Object.
>>>>> >>>>>
>>>>> >>>>> Simon J D Cox
>>>>> >>>>> Research Scientist
>>>>> >>>>> Land and Water
>>>>> >>>>> CSIRO
>>>>> >>>>> E simon.cox@csiro.au <mailto:simon.cox@csiro.au> T +61 3 9545
>>>>> >>>>> 2365 M +61 403 302 672
>>>>> >>>>> Physical: Reception Central, Bayview Avenue, Clayton, Vic 3168
>>>>> >>>>> Deliveries: Gate 3, Normanby Road, Clayton, Vic 3168
>>>>> >>>>> Postal: Private Bag 10, Clayton South, Vic 3169
>>>>> >>>>> people.csiro.au/C/S/Simon-Cox
>>>>> >>>>> <http://people.csiro.au/C/S/Simon-Cox>
>>>>> >>>>> orcid.org/0000-0002-3884-3420
>>>>> >>>>> <http://orcid.org/0000-0002-3884-3420>
>>>>> >>>>> researchgate.net/profile/Simon_Cox3
>>>>> >>>>> <http://researchgate.net/profile/Simon_Cox3>
>>>>> >>>>>
>>>>> >>>>> ________________________________________
>>>>> >>>>> From: Joshua Lieberman <jlieberman@tumblingwalls.com
>>>>> >>>>> <mailto:jlieberman@tumblingwalls.com>>
>>>>> >>>>> Sent: Wednesday, 1 June 2016 7:12 AM
>>>>> >>>>> To: Andrea Perego
>>>>> >>>>> Cc: Linda van den Brink; Frans Knibbe; SDW WG
>>>>> >>>>> (public-sdw-wg@w3.org <mailto:public-sdw-wg@w3.org>)
>>>>> >>>>> Subject: Re: Agenda for Best Practice sub-group, 14:00UTC
>>>>> >>>>> 1-June-2016
>>>>> >>>>>
>>>>> >>>>>> On May 31, 2016, at 10:01 AM, Andrea Perego
>>>>> >>>>>> <andrea.perego@jrc.ec.europa.eu
>>>>> >>>>>> <mailto:andrea.perego@jrc.ec.europa.eu>> wrote:
>>>>> >>>>>>
>>>>> >>>>>> Dear Linda, dear Frans, dear Josh,
>>>>> >>>>>>
>>>>> >>>>>> About the agenda item on "spatial ontology", I wonder whether
>>>>> >>>>>> we can include here a clarification on the notions of spatial
>>>>> >>>>>> object, feature and geometry in GeoSPARQL - in relation to
>>>>> >>>>>> ISO, and to our discussion on real-world / spatial things.
>>>>> >>>>>>
>>>>> >>>>>> In particular:
>>>>> >>>>>>
>>>>> >>>>>> 1. In GeoSPARQL, feature and geometry are explicitly mapped to
>>>>> >>>>>> the corresponding notions in the relevant ISO standards.
>>>>> >>>>>> However, the definition of spatial object in GeoSPARQL doesn't
>>>>> >>>>>> seem to match to the ISO one ("object used for representing a
>>>>> >>>>>> spatial characteristic of a feature" - ISO 19107).
>>>>> >>>>>
>>>>> >>>>> Yes, it's questionable whether GF_Feature should be considered
>>>>> >>>>> a "Spatial Object". In ISO 19109, it's a real-world target of
>>>>> >>>>> discourse, that can have properties, including one or more
>>>>> >>>>> geometric model representations. I'm tending towards making
>>>>> >>>>> GF_Feature an owl:Thing, and leaving GM_Object as a
>>>>> SpatialObject.
>>>>> >>>>>>
>>>>> >>>>>> 2. What in GeoSPARQL corresponds to real-world / spatial
>>>>> things?
>>>>> >>>>>>
>>>>> >>>>>> Thanks
>>>>> >>>>>>
>>>>> >>>>>> Andrea
>>>>> >>>>>>
>>>>> >>>>>>
>>>>> >>>>>> On 30/05/2016 10:22, Linda van den Brink wrote:
>>>>> >>>>>>> Hi all,
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>> The Best Practice sub-group telecon agenda is at
>>>>> >>>>>>>
>>>>> https://www.w3.org/2015/spatial/wiki/Meetings:BP-Telecon20160601.
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>> Main agenda:
>>>>> >>>>>>>
>>>>> >>>>>>> * Progress of BP Narrative 2
>>>>> >>>>>>>
>>>>> >>>>>>> * Spatial ontology
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>> See you all on Wednesday! (else please advise any regrets).
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>>
>>>>> >>>>>>> Linda
>>>>> >>>>>>>
>>>>> >>>>>>
>>>>> >>>>>> --
>>>>> >>>>>> 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/
>>>>> >>>>>>
>>>>> >>>>>>
>>>>> >>>>>
>>>>> >>>>>
>>>>> >>>>>
>>>>> >>>>
>>>>> >>>>
>>>>> >>>>
>>>>> >>>>
>>>>> >>>
>>>>> >>> <SpatialObject.png><SpatialObject.png>
>>>>> >>
>>>>>
>>>>> --
>>>>> 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/
>>>
>>
>
>

-- 
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/

Received on Wednesday, 8 June 2016 22:36:42 UTC