W3C home > Mailing lists > Public > public-sdw-wg@w3.org > February 2017

RE: Non-dereferencable URIs (was Re: ACTION-255 - o&m alignment)

From: <Simon.Cox@csiro.au>
Date: Thu, 9 Feb 2017 00:52:57 +0000
To: <rob@metalinkage.com.au>, <armin.haller@anu.edu.au>, <jano@geog.ucsb.edu>, <phila@w3.org>
CC: <public-sdw-wg@w3.org>
Message-ID: <5f8ddf6675b94f8c843e0c158b90288c@exch1-mel.nexus.csiro.au>
PROPOSED: Alignment of SOSA/SSN with O&M shall denote classes and properties from the ISO 19156 O&M UML model using URIs which are defined in ISO 19150-2, and are currently visible in ontology files available from https://github.com/ISO-TC211/GOM/tree/master/isotc211_GOM_harmonizedOntology/19156/2011



From: Rob Atkinson [mailto:rob@metalinkage.com.au]
Sent: Thursday, 9 February, 2017 11:05
To: Armin Haller <armin.haller@anu.edu.au>; Rob Atkinson <rob@metalinkage.com.au>; Krzysztof Janowicz <jano@geog.ucsb.edu>; Phil Archer <phila@w3.org>
Cc: Cox, Simon (L&W, Clayton) <Simon.Cox@csiro.au>; SDW WG Public List <public-sdw-wg@w3.org>
Subject: Re: Non-dereferencable URIs (was Re: ACTION-255 - o&m alignment)

great,  can we attempt to have the proposers having the correct form of the proposal ready to vote on - we lose a lot of time trying to paraphrase a proposition into the proposal form in the meeting...


On Thu, 9 Feb 2017 at 10:32 Armin Haller <armin.haller@anu.edu.au<mailto:armin.haller@anu.edu.au>> wrote:
As mentioned in our last call, I will put Simon’s proposal for the use of the ISO TC211 URIs on the agenda for our next meeting. Also, Krzysztof’s proposal how to circumvent the non-existence of dereferencable URIs makes sense to me and is worth considering as a proposal in the call.

From: Rob Atkinson <rob@metalinkage.com.au<mailto:rob@metalinkage.com.au>>
Date: Wednesday, 8 February 2017 at 10:14 pm
To: Krzysztof Janowicz <jano@geog.ucsb.edu<mailto:jano@geog.ucsb.edu>>, Phil Archer <phila@w3.org<mailto:phila@w3.org>>
Cc: Simon Cox <Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au>>, SDW WG Public List <public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>>
Subject: Re: Non-dereferencable URIs (was Re: ACTION-255 - o&m alignment)
Resent-From: <public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>>
Resent-Date: Wednesday, 8 February 2017 at 10:15 pm

+1


On Wed, 8 Feb 2017 at 18:10 Krzysztof Janowicz <jano@geog.ucsb.edu<mailto:jano@geog.ucsb.edu>> wrote:
>I doubt this would be helpful but we could perhaps mint new ones that did dereference and assert >equivalence but that's only worth doing if it provides some functionality that's actually useful.
I had the same (or similar) idea but it was already past 2 pm and we closed the meeting. What we could do is to have an ontology that has dereferencable URIs for all the classes and properties and for each of them would also contain rdfs:isDefinedBy statements that point to the O&M/ISO URIs. rdfs:isDefinedBy explicitly does not put any constraints on such resources, they do not even have to be Web-available (https://www.w3.org/TR/rdf-schema/#ch_isdefinedby). As a final step, we would establish our mapping axioms in the form of subclass and equivalence class relations from SOSA/SSN to these dereferenceable class and property URLs.
Best,
Jano

On Tue, Feb 7, 2017 at 10:48 PM, Phil Archer <phila@w3.org<mailto:phila@w3.org>> wrote:
I'm sorry I wasn't able to speak about this on the call. By the time this topic came up I was being driven along the road and had insufficient bandwidth to un-mute myself although I could hear the conversation.

Of course dereferencable URIs are preferred over non-dereferencable ones. However, this should not be seen as an absolute requirement or diktat. If there are good reasons to use non-dereferencable URIs - and it sounded to me as if Simon was making a very strong case for their use - and if the non-dereferencable state causes no harm, then go ahead.

The question is, of course, can TC211 be encouraged to make things like http://def.isotc211.org/iso19156/2011/ dereferencable? If it helps, we'd happily host the relevant data to which those URIs could redirect (I'm sure OGC and others would too of course).

I doubt this would be helpful but we could perhaps mint new ones that did dereference and assert equivalence but that's only worth doing if it provides some functionality that's actually useful.

Phil



On 07/02/2017 22:26, Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au> wrote:
I've dropped it into a Wiki page here (formatting not yet complete).

https://www.w3.org/2015/spatial/wiki/Alignment_to_O%26M


This should help with your namespace and prefix questions Laurent.

From: Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au> [mailto:Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au>]
Sent: Wednesday, 8 February, 2017 08:35
To: public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>
Subject: [ExternalEmail] RE: ACTION-255 - o&m alignment

If you are unable to see the section in the HTML in the branch, here is the proposed text:

-----------------------

8. Alignment to Observations and Measurements

This section introduces the alignment of SOSA/SSN to OGC Observations and Measurements [OandM] (also known as ISO 19156:2011).

O&M is specified as a UML model, following the patterns specified in ISO 19109 Geographic Information - Rules for Application Schema [ISO-19109]. This means that the classes represent concepts from the application domain, so can be approximately equated with classes in an ontology.

Two OWL implementations of O&M have been described:

an explicit translation of the UML following the rules specified in [ISO-19150-2] - see [OM-Heavy]; and
a handcrafted version in more idiomatic OWL [OM-Lite].
The following sections provide two mappings or alignments between SOSA/SSN and O&M: the first with the official ISO/OGC UML conceptual model, and the second with the lightweight OWL implementation.

8.1 Alignment to Observations and Measurements UML model

This section is non-normative.

The explicit translation generates an RDF entity for every class, class attribute, and association-role from the original O&M UML model. It comes at a cost of a large set of dependencies on similar OWL translations of other UML models from the ISO 19100 series. Nevertheless, the URI for each RDF entity is a convenient identifier to elements of the UML model. These can be used to identify the elements of O&M in a formal RDF/OWL alignment.

Rules for generating the URIs are provided in [ISO-19150-2], and appear in the official OWL implementation of ISO 19156 (O&M) maintained by the ISO/TC 211 Group on Ontology Management.

The following namespace prefixes are used in the alignment to SOSA.

Prefix   Namespace
sosa:    http://www.w3.org/ns/sosa/

sosa-om:          http://www.w3.org/ns/sosa-om#<http://www.w3.org/ns/sosa-om>
iso19156-gfi:   http://def.isotc211.org/iso19156/2011/GeneralFeatureInstance#<http://def.isotc211.org/iso19156/2011/GeneralFeatureInstance>
iso19156-om:  http://def.isotc211.org/iso19156/2011/Observation#<http://def.isotc211.org/iso19156/2011/Observation>
iso19156-sf:     http://def.isotc211.org/iso19156/2011/SamplingFeature#<http://def.isotc211.org/iso19156/2011/SamplingFeature>
iso19156-sfs:   http://def.isotc211.org/iso19156/2011/SpatialSamplingFeature#<http://def.isotc211.org/iso19156/2011/SpatialSamplingFeature>
iso19156-sp:    http://def.isotc211.org/iso19156/2011/Specimen#<http://def.isotc211.org/iso19156/2011/Specimen>
Utility classes

Five utiity classes are defined locally to support the formalization of the alignment.

1. Three disjoint subclasses of sosa:Procedure:

sosa-om:ActuationProcedure Actuation procedures or recipes
sosa-om:ObservationProcedure         Observation procedures or recipes
sosa-om:SamplingProcedure  Sampling, sample preparation or processing procedures or recipes
2. Two classes related to sampling, which complement SOSA classes related to actuation and observation:

sosa-om:SamplingDevice        Sampling, sample preparation or processing devices, comparable to sosa:Actuator and sosa:Sensor
sosa-om:SamplingEvent          Sampling, sample preparation or processing event or act, comparable to sosa:Actuation and sosa:Observation
Class alignments

The primary classes from [OandM] have direct equivalents in SOSA classes supplemented by the utility classes described above, as follows:

iso19156-om:OM_Observation          equivalent class          sosa:Observation
iso19156-om:OM_Process      equivalent class          sosa:Sensor or sosa-om:ObservationProcedure
iso19156_sf:SF_SamplingFeature       equivalent class          sosa:Sample
iso19156-sf:SF_Process           equivalent class          sosa-om:SamplingDevice or sosa-om:SamplingProcedure
Additional alignments from SOSA/SSN classes to O&M classes are as follows.

sosa:FeatureOfInterest           subclass of       iso19156_gfi:GFI_DomainFeature
where iso19156_gfi:GFI_DomainFeature has the definition:

The class GFI_DomainFeature represents 'real-world' features which are the ultimate subject of an observation campaign, i.e. the features from an application domain that are not artefacts of the observation process (sampling features).
sosa:Actuator  subclass of       iso19156_gfi:GFI_Feature
sosa:Platform  subclass of       iso19156_gfi:GFI_Feature
where iso19156_gfi:GFI_Feature has the definition

The class GFI_Feature represents the set of all classes which are feature types. In an implementation this abstract class shall be substituted by a concrete class representing a feature type from an application schema associated with a domain of discourse (ISO 19109, ISO 19101).
Property alignments

The following properties from [OandM] have direct equivalents in SOSA properties:

iso19156-om:OM_Observation.featureOfInterest     equivalent property    sosa:hasFeatureOfInterest
iso19156-om:OM_Observation.observedProperty    equivalent property    sosa:observedProperty
iso19156-om:OM_Observation.phenomenonTime    equivalent property    sosa:phenomenonTime
iso19156-sf:SF_SamplingFeature.sampledFeature    equivalent property    sosa:isSampleOf
Additional alignments from O&M properties to SOSA are as follows.

iso19156-om:OM_Observation.procedure    sub-property of           sosa:usedProcedure
iso19156-sp:SF_Specimen.samplingMethod  sub-property of           sosa:usedProcedure
These alignments are modeled as sub-properties because sosa:usedProcedure applies to actuation, observation or sampling activities.

iso19156-om:OM_Observation.result            sub-property of           sosa:hasResult
iso19156-om:OM_Observation.resultTime    sub-property of           sosa:resultTime
iso19156-sp:SF_Specimen.samplingTime       sub-property of           sosa:resultTime
iso19156-sp:PreparationStep.time     sub-property of           sosa:resultTime
These alignments are modeled as sub-properties because sosa:hasResult and sosa:resultTime applies to actuation, observation or sampling activities.

iso19156-sfs:SF_SpatialSamplingFeature.hostedProcedure   sub-property of           sosa:hosts
These alignments are modeled as a sub-property because the domain of iso19156-sfs:SF_SpatialSamplingFeature.hostedProcedure is a spatial sampling feature, such as a station, rather than a more general platform.

An RDF file containing a graph corresponding to this alignment is available.

8.2 Alignment to om-lite implementation of Observations and Measurements

This section is non-normative.

An idiomatic OWL implementation of O&M (including Sampling Features) is described in [OM-Lite].

The following namespace prefixes are used in the alignment to SOSA.

Prefix   Namespace
sosa:    http://www.w3.org/ns/sosa/

sosa-oml:         http://www.w3.org/ns/sosa-oml#<http://www.w3.org/ns/sosa-oml>
oml:     http://def.seegrid.csiro.au/ontology/om/om-lite#<http://def.seegrid.csiro.au/ontology/om/om-lite>
samfl:  http://def.seegrid.csiro.au/ontology/om/sam-lite#<http://def.seegrid.csiro.au/ontology/om/sam-lite>
Utility classes

Five utiity classes are defined locally to support the formalization of the alignment.

1. Three disjoint subclasses of sosa:Procedure:

sosa-oml:ActuationProcedure Actuation procedures or recipes
sosa-oml:ObservationProcedure        Observation procedures or recipes
sosa-oml:SamplingProcedure Sampling, sample preparation or processing procedures or recipes
2. Two classes related to sampling, which complement SOSA classes related to actuation and observation:

sosa-oml:SamplingDevice       Sampling, sample preparation or processing devices, comparable to sosa:Actuator and sosa:Sensor
sosa-oml:SamplingEvent         Sampling, sample preparation or processing event or act, comparable to sosa:Actuation and sosa:Observation
Class alignments

The primary classes from [OM-Lite] have direct equivalents in SOSA classes supplemented by the utility classes described above, as follows:

oml:Observation         equivalent class          sosa:Observation
oml:Process     equivalent class          sosa:Sensor or sosa-om:ObservationProcedure
samfl:SamplingFeature           equivalent class          sosa:Sample
samfl:Process  equivalent class          sosa-om:SamplingDevice or sosa-om:SamplingProcedure
Property alignments

The following properties from [OM-Lite] have direct equivalents in SOSA properties:

oml:featureOfInterest equivalent property    sosa:hasFeatureOfInterest
oml:observedProperty            equivalent property    sosa:observedProperty
oml:phenomenonTime           equivalent property    sosa:phenomenonTime
samfl:sampledFeature            equivalent property    sosa:isSampleOf
Additional alignments from [OM-Lite] properties to SOSA are as follows.

oml:procedure            sub-property of           sosa:usedProcedure
samfl:samplingMethod           sub-property of           sosa:usedProcedure
These alignments are modeled as sub-properties because sosa:usedProcedure applies to actuation, observation or sampling activities.

oml:result        sub-property of           sosa:hasResult
oml:resultTime           sub-property of           sosa:resultTime
samfl:samplingTime   sub-property of           sosa:resultTime
These alignments are modeled as sub-properties because sosa:hasResult and sosa:resultTime applies to actuation, observation or sampling activities.

samfl:hostedProcedure           sub-property of           sosa:hosts
These alignments are modeled as a sub-property because the domain of iso19156-sfs:SF_SpatialSamplingFeature.hostedProcedure is a spatial sampling feature, such as a station, rather than a more general platform.

An RDF file containing a graph corresponding to this alignment is available.


From: Cox, Simon (L&W, Clayton)
Sent: Tuesday, 7 February, 2017 15:58
To: 'Simon.Cox@csiro.au' <Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au>>>; public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org><mailto:public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>>
Subject: RE: ACTION-255 - o&m alignment

Note that this mapping is only from SOSA to O&M (and om-lite).

I also intend to look at the mapping from 'SSN' (i.e. the vertical axiomatization/extension) of SOSA for observations and sensing through to O&M. Much of the intended alignment was captured in annotations in the original ontology, but the discussions in the last week suggest that some local-names might change else SOSA classes and properties used in place of old SSN equivalents. When this has settled down a comprehensive mapping should be formulated.

Probably the key question arising from the work mentioned below is whether the proposal to use the URIs that are specified in the translation of the UML model to OWL, following the ISO 19150-2 rules, is acceptable.

Pro:

-          It allows us to express the alignment formally within the idiom we are working in (OWL)
Cons:

-          The OWL version of O&M is not in itself published as a 'standard' and the URIs are not directly resolvable (yet, anyway)

o   However, as pointed out in the document, the URIs are persistent identifiers in the view of ISO, and the fact that ISO's process does not require a separate document for the OWL implementation should be OK for us

-          UML and OWL are so different in their assumptions that it is a fallacy to use the OWL implementation as representing the UML model

I'm sure there are other arguments. My feeling is that the proposed approach balances formality and pragmatism OK.

Simon

From: Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au>> [mailto:Simon.Cox@csiro.au<mailto:Simon.Cox@csiro.au>]
Sent: Saturday, 28 January, 2017 21:33
To: public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org><mailto:public-sdw-wg@w3.org<mailto:public-sdw-wg@w3.org>>
Subject: [ExternalEmail] ACTION-255 - o&m alignment

In response to my ACTION-255 from last week's meeting, I have generated two RDF files containing formal alignments between SOSA and O&M.

-          sosa-om-mapping.ttl relates to the O&M UML model, and uses the Official ISO URIs from the OWL implementation prepared by the ISO/TC 211 Group on Ontology Management following the rules from ISO 19150-2

-          sosa-oml-mapping.ttl relates to the om-lite and sam-lite OWL implementation recently published in Semantic Web Journal

I have also prepared text for the SSN document describing these mappings - for chapter 8 in the spec.
So far the mappings only concern SOSA.

I've pushed all this into a branch in GitHub https://github.com/w3c/sdw/tree/simon-ssn-O%26M-alignments/ssn

and issued a pull-request https://github.com/w3c/sdw/pull/516


Simon

Simon J D Cox
Research Scientist
Environmental Informatics
CSIRO Land and Water<http://www.csiro.au/Research/LWF>

E simon.cox@csiro.au<mailto:simon.cox@csiro.au<mailto:simon.cox@csiro.au>> T +61 3 9545 2365<tel:%2B61%203%209545%202365> M +61 403 302 672<tel:%2B61%20403%20302%20672>
   Mail: Private Bag 10, Clayton South, Vic 3169
   Visit: Central Reception, Research Way, Clayton, Vic 3168
   Deliver: Gate 3, Normanby Road, Clayton, Vic 3168
people.csiro.au/Simon-Cox<http://people.csiro.au/Simon-Cox><http://people.csiro.au/Simon-Cox>
orcid.org/0000-0002-3884-3420<http://orcid.org/0000-0002-3884-3420><http://orcid.org/0000-0002-3884-3420>
researchgate.net/profile/Simon_Cox3<http://researchgate.net/profile/Simon_Cox3><https://www.researchgate.net/profile/Simon_Cox3>
github.com/dr-shorthair<http://github.com/dr-shorthair><https://github.com/dr-shorthair>

PLEASE NOTE
The information contained in this email may be confidential or privileged. Any unauthorised use or disclosure is prohibited. If you have received this email in error, please delete it immediately and notify the sender by return email. Thank you. To the extent permitted by law, CSIRO does not represent, warrant and/or guarantee that the integrity of this communication has been maintained or that the communication is free of errors, virus, interception or interference.

Please consider the environment before printing this email.


--


Phil Archer
Data Strategist, W3C
http://www.w3.org/


http://philarcher.org

+44 (0)7887 767755<tel:%2B44%20%280%297887%20767755>
@philarcher1

Received on Thursday, 9 February 2017 00:54:35 UTC

This archive was generated by hypermail 2.4.0 : Thursday, 24 March 2022 20:31:29 UTC