- From: <andrea.perego@ec.europa.eu>
- Date: Sat, 1 Jul 2017 00:10:47 +0000
- To: <public-dxwg-wg@w3.org>
- CC: <phila@w3.org>
Dear colleagues,
I've been able to read the minutes only today, and I would like to contribute a few comments on the use case under discussion (which I submitted). Before that, my sincere apologies for not having been able to join the call.
1. I agree that the title ("Modeling temporal coverage") is too broad for the described use case, which deals only on how to specify a period with start/end dates. There are indeed different ways of specifying temporal coverage, as discussed during the call, that in many cases depend on the domain, and may be more or less fuzzy (as periods like the Middle Ages and geological eras). Actually, this issue has been one of the subjects of discussion in the SDW WG in relation to "time", and has brought requirements for the work on the OWL Time Ontology led by Simon. I have not included other scenarios in the use case just because I have no real-world examples at hand, whereas the start/end date issue is related to use cases widely implemented and which I'm familiar with. It makes sense to me that the existing alternatives are described in different use cases.
2. About the comment on the complexity of OWL Time, the point I was trying to make is not that it is not fit for specifying temporal coverage in general. Rather, the issue is that different ways of specifying temporal coverage (start/end date, periods, etc.) may require different ways of modelling it (e.g., a dct:Period + schema:startDate / schema:endDate, as in ADMS/DCAT-AP, or a more articulated representation, as done in OWL Time). I think that what would be beneficial for the community using DCAT is to provide harmonised patterns for the different use cases - not only to provide guidance, but also to facilitate interoperability.
3. What said in point (2) applies also to the use case related to "spatial" coverage [1]. There are different ways of specifying this information - the use case mentions 2 of them: geographical names, and geometries (spatial coordinates - as we may have temporal coordinates in temporal coverage). And we also have different levels of fuzziness. So, there's a relationship between the two that may be worth taking into account.
4. I see there was also a discussion on different "types" of dates, and Alejandra pointed to those supported by DataCite. On the mapping of DataCite to DCAT-AP we carried out a preliminary study at JRC, documented at [2]. As far as dates are concerned, the DataCite ones are basically those already defined in Dublin Core, with the only exception of "date collected". You can check the correspondences in the relevant mapping table, available at:
https://webgate.ec.europa.eu/CITnet/stash/projects/ODCKAN/repos/datacite-to-dcat-ap/browse/documentation/Mappings.md
Cheers,
Andrea
----
[1]https://www.w3.org/2017/dxwg/wiki/Use_Case_Working_Space#Modeling_spatial_coverage
[2]https://webgate.ec.europa.eu/CITnet/stash/projects/ODCKAN/repos/datacite-to-dcat-ap/
----
Andrea Perego, Ph.D.
Scientific / Technical Project Officer
European Commission DG JRC
Directorate B - Growth and Innovation
Unit B6 - Digital Economy
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.
________________________________________
From: Phil Archer [phila@w3.org]
Sent: 26 June 2017 17:15
To: public-dxwg-wg@w3.org
Subject: [Minutes] 2017 06 26
The minutes of today's minutes are at
https://www.w3.org/2017/06/26-dxwg-minutes with a snapshot below.
Thanks to Lars for scribing.
Dataset Exchange Working Group Teleconference
26 June 2017
[2]Agenda [3]IRC log
[2] https://www.w3.org/2017/dxwg/wiki/Meetings:Telecon2017.06.26
[3] http://www.w3.org/2017/06/26-dxwg-irc
Attendees
Present
achille_zappa, alejandra, annette_g, Caroline_,
Dave_Browning, Jaroslav_Pullmann, kcoyle, LarsG, Makx,
mathieu, MJ_Han, nandana, phila, RiccardoAlbertoni, Rob
Atkinson, SimonCox, Thomas
Regrets
Antoine, Colleen_Fallaw, Eric_Stephan, Luiz, Martin,
Newton, Peter_Winstanley, Ruben
Chair
Karen Coyle
Scribe
LarsG
Contents
* [4]Meeting Minutes
1. [5]Preliminaries
2. [6]Approve last week's meeting minutes
3. [7]new attendees?
4. [8]Reports from sub-groups
5. [9]Research Data
* [10]Summary of Resolutions
Meeting Minutes
Approve last week's meeting minutes
Resolved: approved last weeks minutes (NOTUC)
new attendees?
No new attendees
Reports from sub-groups
No reports from sub-groups
kcoyle: wants to know if DCAT group has met
alejandra: DCAT has exchanged a few emails but hasn't met yet.
… will keep us posted
kcoyle: so far we have approved three use cases
… today we discuss are modelling temporal coverage,
… modelling spatial coverage
… and data access restrictions.
<kcoyle> [11]https://www.w3.org/2017/dxwg/wiki/
Use_Case_Working_Space#Modeling_temporal_coverage
[11]
https://www.w3.org/2017/dxwg/wiki/Use_Case_Working_Space#Modeling_temporal_coverage
temporal coverage submitted by Andrea (who isn't here)
<SimonCox> Make sure to use [12]https://www.w3.org/TR/owl-time/
:-)
[12] https://www.w3.org/TR/owl-time/
... DCAT say to use dct:temporal
... SimonCox proposes owl-time
<alejandra> Can we add to the links the following ones:
[13]http://github.com/biocaddie/WG3-MetadataSpecifications
[13] http://github.com/biocaddie/WG3-MetadataSpecifications
<alejandra> and [14]https://developers.google.com/search/docs/
data-types/datasets
[14] https://developers.google.com/search/docs/data-types/datasets
<SimonCox> [15]https://www.w3.org/TR/owl-time/#time:hasEnd etc
[15] https://www.w3.org/TR/owl-time/#time:hasEnd
<alejandra> where also temporal coverage have been considered
kcoyle: If people have more links, they can add that to the
wiki page
Makx: reacting to Andrea ADMS and DCAT-AP use schema:start and
schema:end since owl-time looked too complicated
… many European data portals use that, too
<roba_> * online for next 30 mins
alejandra: Question about process: When I have comments or
links
… can I modify the UC directly in the Wiki or should it go
through the UC editors?
<mathieu> owl-time seems complicated but there can be more
complex things to represent than just start and end dates
<roba_> +1 to put to working use cases document.
Present__Ixchel: If it's something that hasn't been discussed
yet, just add it so that it's there for the meeting. Otherwise
send an email to the editors
<Jaroslav_Pullmann> thanks!
Present__Ixchel: and they'll add it
alejandra: Agrees with that process.
kcoyle: From XXX there is a link to the working space
kcoyle: there is no way to see which UCs we have discussed just
by looking at the list
Roba: plans to put a link to the consolidate use case
… status is more complicated
… some things may be solved, others not
… e. g. profile might be discussed but discovery of profiles
not
kcoyle: You can split the UCs to have more atomic parts.
… important for people to see what is resolved
<alejandra> I think that is good
<alejandra> to add things to use cases that have not been
discussed
Makx: has put something in alejandra's UC. Has marked with his
name but wants to know if that's OK
Present__Ixchel: Good idea.
<alejandra> I agree on pinging the original author
Present__Ixchel: If you want the orig author to look at it
again, send a mail to the author
… and the list
Jaroslav_Pullmann: Finds Makx's approach a good idea.
… People can use the comment section
… Status intended to be used as a progress indicator
… has started to create a mind map for the UC (has lost
overview)
… prepares a graphical view of the UCs
… will share the URL
<kcoyle> ack
kcoyle: should we mark this UC as good, can we vote?
<phila> -> [16]https://www.w3.org/2017/dxwg/wiki/
Use_Case_Working_Space#Modeling_temporal_coverage
[16]
https://www.w3.org/2017/dxwg/wiki/Use_Case_Working_Space#Modeling_temporal_coverage
<phila> [17]Modelling Temporal Coverage
[17]
https://www.w3.org/2017/dxwg/wiki/Use_Case_Working_Space#Modeling_temporal_coverage
<kcoyle> [18]https://www.w3.org/2017/dxwg/wiki/
Use_Case_Working_Space#Modeling_temporal_coverage
[18]
https://www.w3.org/2017/dxwg/wiki/Use_Case_Working_Space#Modeling_temporal_coverage
kcoyle: question is: Is it a valid UC that reflects
requirements?
annette_g: There are more complicated cases
… they should be expanded through discussion
alejandra: Edge cases not so important
SimonCox: Title is wrong. More about serialisation (how to
serialise beginning and end)
<roba_> modelling is covered by scope of [19]http://
w3c.github.io/sdw/qb4st/
[19] http://w3c.github.io/sdw/qb4st/
SimonCox: the description points out that in DCAT a URI is used
to describe the time. That is considered cumbersome
… it's about the representation, not the content
… per se
… that is an old problem, when the issue is about modelling and
when about syntax/representation
kcoyle: Suggests to change the title
roba_: It's neither syntax nor modelling, but more about a
summary: DCAT proposes simplified view. Author might
… be simple, but provenance more deeply modelled
… spatio-temporal extent can be done through QB4ST as begun in
SDW
Jaroslav_Pullmann: agrees. This is more about representation
(date format) and might break down into simple properties
… part of an overall modelling context
… and that way put into a bigger relation
Present__Ixchel: speaking from the user perspective. It's about
understanding the different kind of temporal coverage. E. g.
start and end of
… data acquisition. It's about bringing data together using
their temporal contexts
alejandra: Agrees. We also need to discuss the capabilities of
DCAT. Obvious cases are dataset creation and modification. But
also acceptance on DataCite.
<phila> +1 to alejandra I was going to same something similar
alejandra: We need a very flexible way to handle different
kinds of dates
Makx: Wonders if it's useful to change the scope of a UC. The
UC builds on a real need and is a simple requirement.
… There are also a wider issue of modelling temporal aspects
… but not in this UC
<Thomas> Agreed, Makx
Jaroslav_Pullmann: relevance of the data is also important when
searching for data in a catalogue.
… Some dates are fixed (distribution etc.).
… DCAT already has the catalogue record element for such
things.
… Makx's focus is the temporal data itself, not of the dataset
kcoyle: Do we need another UC?
<SimonCox> types of dates - will it be a closed list?
Jaroslav_Pullmann: Yes, maybe a meta-UC
kcoyle: There is a problem putting too much into a single UC
… better to have simple specific UCs
… Who can do that?
alejandra: DataCite has specific types of dates.
… that's an existing approach we can follow
… E. g. when the data was collected. That goes into processes
<Makx> keep this one as it is, please
roba_: This UC is about what we want to put into simple
properties in DCAT. Should have a simple model.
… We probably don't need another UC for that
… but should have one simple UC (as a meta-UC) and one more
deeply into modelling
… We can add another UC to the working space and map that to
the existing
<riccardoAlbertoni> +1 to kcoyle "adding further use cases on
time issues" and keep this uc simple.
Jaroslav_Pullmann: Would this be a UC like "temporal aspects in
DCAT"?
… and then bring everything temporal into that
kcoyle: we shouldn't be too abstract
<Makx> +1 to keeping things practical
kcoyle: when we look at UCs at a high level they have much in
common
… but we need to keep it practical
Jaroslav_Pullmann: thought we could have one for all temporal
dimensions in DCAT (API availability) all rooted in one meta-UC
kcoyle: Jaroslav_Pullmann shouldn't hesitate to create one if
needed
<Makx> I vote for keeping it
kcoyle: shall we edit the UC first or can we vote directly?
<annette_g> +1 for keeping it but adding what's missing
Jaroslav_Pullmann: agrees with Makx that we should edit the UC
first
<Makx> what is missing?
<roba_> agree with keeping it but rename it - its not
modelling..
<kcoyle> PROPOSE: accept ID29 and edit it to be specifically
about start and end dates; and modify title to remove modeling
SimonCox: does that mean start and end date of the data set
(the record)?
<Makx> this is the data itself
<Makx> no this is not want the UC is about
<roba_> record is overloaded term.. be careful
Jaroslav_Pullmann: it's about the adding to the catalogue (the
record) not the contents of the data set.
<roba_> i think we are talking about the temporal coverage of
the data - but we need to narrow down the semantics -
observation time or phenomemon time
SimonCox: the date of an observation is not always the same as
what we are interested in (e. g. geological discovery vs.
geological event)
… there are properties for that
<kcoyle> acvk SimonCox
<kcoyle> PROPOSED: accept ID29 and edit it to be specifically
about start and end dates of the dataset; and modify title to
remove modeling
<alejandra> +1
Makx: wants to clarify: it's about the year the (budget) data
applies to, not about when the dataset was created
Jaroslav_Pullmann: So it's about the temporal context of the
data (phenomenon time), not about observation time
SimonCox: Yes
annette_g: Thought this would be more about deep thoughts about
start and end dates. We shouldn't remove those from the UC or
the discussion
<Makx> disagree with extending use cases too much
alejandra: the UC talks about start and end date. But when you
work with time series you want intermediate points, too. That's
also part of temporal coverage
<Makx> intermittent periods is covered because dct:coverage is
repeatable
alejandra: similar things in other UCs
kcoyle: we need more UCs on that topic
SimonCox: we need to be more clear about specific requirements
vs cross-domain reqs
… [other WG had 13 different kinds of dates]
… that was a very specialised application (weather forecasting)
… and there might be scientific cases in the future
… which leaves us with the dilemma that DCAT is
… general purpose which needs to be applicable in several
… domains but also needs to be applied to specific communities'
needs
… We need to find the right balance
Thomas: doesn't think we can capture all semantics in one
simple model
… the dataset describer needs to use what works for them
… In specialist datasets there are dates that care for
phenomenon time
annette_g: we shouldn't try to make DCAT work for all
scientific communities, but it should be easier to use if for
the scientific community (uptake has been slow)
<kcoyle> PROPOSED: accept ID27 and edit it to be specifically
about start and end dates of the dataset; and modify title to
remove modeling
<Makx> +1
<roba_> +1
<SimonCox> +1
<annette_g> +1
<Caroline_> +1
<Thomas> +1
<mathieu> +1
<Jaroslav_Pullmann> +1
<achille_zappa> +1
<riccardoAlbertoni> +1
<phila> +1
<Dave_Browning> +1
<nandana> +1
+1
<Present__Ixchel> it's ID27
<MJ_Han> +1
<Present__Ixchel> +1
alejandra: if we remove modelling, does that mean that we only
talk about start and end dates?
<alejandra> +1
<roba_> Can we review UC1 to see if it covers general modelling
of aspects, including time and suggest improvements please
kcoyle: we can add modelling back again if necessary, but for
now, yes
<roba_> review offline
<MJ_Han> In Requirements, spatial should be temporal.
kcoyle: yes, roba_ , we can do that on the list or at the
Oxford F2F
Research Data
phila: Talked to WG chairs of RDA and then with people at
CODATA (umbrella body for science unions)
… much potential interest in this WG but also in the general
… idea of research data as shared information on the web
… phila plans to continue with this
… RDA und CODATA watch this WG in order to make the web
… a large information space
<annette_g> +1 exciting stuff!
<SimonCox> As phila mentioned, I'm involved with RDA and CODATA
so will keep links intact
kcoyle: next week we'll discuss more UCs
phila: If we discuss the outputs of this group in a subgroup,
keep the mailing list in the loop to have it public
<Caroline_> +1 to discuss in public :)
<Caroline_> bye! thank you!
<roba_> bye all
<annette_g> bye!
<riccardoAlbertoni> bye...
<SimonCox> good night
<Dave_Browning> bye
<Present__Ixchel> bye
<kcoyle> Thanks Lars for scribing!!
Summary of Resolutions
1. [20]approved last weeks minutes (NOTUC)
Received on Saturday, 1 July 2017 00:11:20 UTC