- From: Phil Archer <phila@w3.org>
- Date: Wed, 18 May 2016 16:08:00 +0100
- To: SDW WG Public List <public-sdw-wg@w3.org>
The minutes of today's Coverages Sub Group meeting are at
https://www.w3.org/2016/05/18-sdwcov-minutes with a text snapshot below.
ANU joins reading in being able to point to live demos, running code etc :-)
Spatial Data on the Web WG Coverages Sub Group
18 May 2016
[2]Agenda
[2]
https://www.w3.org/2015/spatial/wiki/Meetings:Coverage-Telecon20160518
See also: [3]IRC log
[3] http://www.w3.org/2016/05/18-sdwcov-irc
Attendees
Present
ByronCinNZ, billroberts, dmitrybrizhinev, duo, sam,
phila, Maik, Rob, Atkinson, jonblower, kerry
Regrets
ScottSimmons
Chair
billroberts
Scribe
kerry
Contents
* [4]Topics
1. [5]Brief recap of previous meeting
2. [6]Updates on example implementations: ANU
3. [7]University of Reading/CoverageJSON
4. [8]Requirements doc: presentation and review of draft
by Bill
* [9]Summary of Action Items
* [10]Summary of Resolutions
__________________________________________________________
<scribe> scribe: kerry
<billroberts> [11]https://www.w3.org/2016/05/04-sdwcov-minutes
[11] https://www.w3.org/2016/05/04-sdwcov-minutes
<scribe> scribeNick: kerry
<scribe> chair: billroberts
proposed: approve minutes
[12]https://www.w3.org/2016/05/04-sdwcov-minutes
[12] https://www.w3.org/2016/05/04-sdwcov-minutes
<phila> +1
<billroberts> +1
<Duo> +1
<Maik> +1
+1
RESOLUTION: approve minutes
<billroberts>
[13]https://www.w3.org/2015/spatial/wiki/Patent_Call
[13] https://www.w3.org/2015/spatial/wiki/Patent_Call
<billroberts>
[14]https://www.w3.org/2015/spatial/wiki/Meetings:Coverage-Tele
con20160518
[14]
https://www.w3.org/2015/spatial/wiki/Meetings:Coverage-Telecon20160518
Brief recap of previous meeting
<roba> thanks bill - will provide a very quick statement of
intent
billroberts: handy template for FPWD
Updates on example implementations: ANU
<Duo> [15]http://anu-linked-earth-data.github.io/#/
[15] http://anu-linked-earth-data.github.io/#/
Duo: basic demo at link
... very simple client app, have taken a small landsat subset
from agdc and loaded to jena and built client app to access
data as rdf
<Duo> [16]https://github.com/ANU-Linked-Earth-Data/ontology
[16] https://github.com/ANU-Linked-Earth-Data/ontology
Duo: data currently loaded dynamically as RDF datacube in Jena
... 2nd lin is ontology repository, shows datatime, resolution,
band etc
,,,client app does basic time-based search over tiny data, can
click on a particular area
scribe: also a link button to link to data itself, but now a
dummy
... looking for some more data and more complex queries and
multiple bands
jonblower: very nice, but didn't get is ontology describing
pixes or a big binary blob?
Duo: binary blobs becuase pixiels are too big -- we tested this
and discussed at an elalier meeting
<Maik> [17]Sample query
[17]
http://144.6.231.77/landsat/query?query=PREFIX%20xsd%3A%20%3Chttp%3A%2F%2Fwww.w3.org%2F2001%2FXMLSchema%23%3E%20PREFIX%20led%3A%20%3Chttp%3A%2F%2Fwww.example.org%2FANU-LED%23%3E%20SELECT%20%3Fsubject%20%3FgeoSparql%20%3FtimePeriod%20%3Fband%20%3Fimage%20%3Fresolution%20WHERE%20{%3Fsubject%20a%20%3Chttp%3A%2F%2Fpurl.org%2Flinked-data%2Fcube%23Observation%3E.%20%3Fsubject%20%3Chttp%3A%2F%2Fwww.example.org%2FANU-LED%23imageData%3E%20%3Fimage.%20%3Fsubject%20%3Chttp%3A%2F%2Fwww.example.org%2FANU-LED%23etmBand%3E%20%3Fband.%20%3Fsubject%20%3Chttp%3A%2F%2Fwww.example.org%2FANU-LED%23bounds%3E%20%3FgeoSparql.%20%3Fsubject%20%3Chttp%3A%2F%2Fwww.example.org%2FANU-LED%23time%3E%20%3FtimePeriod.%20%3Fsubject%20%3Chttp%3A%2F%2Fwww.example.org%2FANU-LED%23resolution%3E%20%3Fresolution.%20Filter%28%3FtimePeriod%20%3D%20%222012-02-10T23%3A50%3A47.650696%2B00%3A00%22^^xsd%3AdateTime%29}ORDER%20BY%20DESC%28%3FtimePeriod%29%20LIMIT%2025
billroberts: can we ss the rdf?
duo: see query and json result here
... maik has posted [what?]
billroberts: please post a link to the rdf
roba: looking at ontology on link .. has a lot of axes
concepts.. how does this realte to rdf datacube -- it is
different
dmitrybrizhinev: it inherits from rdf-datacube -- are you
looking at right link?
roba: maybe not
<phila> I think it's
[18]https://github.com/ANU-Linked-Earth-Data/ontology/blob/mast
er/ANU-LED.owl
[18]
https://github.com/ANU-Linked-Earth-Data/ontology/blob/master/ANU-LED.owl
<Maik> (my link works, just copy paste it in full, don't click
on it)
dmitrybrizhinev: you need to look at anuld
billroberts: will take a proper look afterwards
Duo: on top of that we had a chat with rob woodcock (AGDC)
about uses of link data and coverage, and a similar chat with
ed parsons
... Rob wants us to be smarter about queries e.g summer above
tropic of capricorn
... or every second month
... does not like resampling becuase sicentists don't like it
<roba> I have already captured these alternative use cases
here:
[19]https://www.w3.org/2015/spatial/wiki/Data_cube_for_coverage
[19] https://www.w3.org/2015/spatial/wiki/Data_cube_for_coverage
Duo: also meeting at ANU Fenner school wher eenvironmental data
on a map was broken into "meaningful" regions
... ed wants to see restful APIs over SPARQL, things that
startups can access
phila: wnat to use some of this for the Chinese project report
... if I were not an rdfhead what is the point?
duo: still early stages... describing data in a meaningful
way.. by having it here can be easier to access.. heading
towards resful approach without sparql
phila: i see a column with diagonal black stripes -- what is
this to a non-expert?
Duo: this is an artifact of lansat -- many people want this -
it is in the data
... if you don't want this this may not be what you want
phila: want to tell people this is a good way to stitch them
together
jonblower: what do users need is a good question? yes
scientists often want it close to original, but others want the
over visual
... good to bring these issues out
bill: creates rquirement for metadata
roba: i know believe that we may not want to turn all inot
rdfdatacube but this is a useful test of the competency of the
model
<phila> Kerry: There's a deeper question in there. The RDF QB
is only appropriate for moderately well developed imagery as
you're assuming it's laid out on a regular grid.
<roba> rdf-QB does not assume a grid. its agnostic about
dimensions
<phila> ... There's a slightly deeper problem, it's not juyst
about what has been done to the data. It's also about how far
we go in saying what the satellite image shows.
<phila> ... I'm happy with this though
<phila> ... What is an appropriate data model for represetning
coverage in general.
<phila> Kerry: Not all coverages map into easy data models
jonblower: convenient that AGDC is thinking about what level of
pre-processing to do
billroberts: we are going to have to deide if we need a suite
of alternative solutions for say unprocessed towads that has
been through a degree of processing
<Zakim> phila, you wanted to make a quick aside about
[20]https://www.w3.org/TR/2016/WD-dwbp-20160519/#EnrichData
[20] https://www.w3.org/TR/2016/WD-dwbp-20160519/#EnrichData
phila: discussion abouit various access to dat reminds me that
DWBP doc that will be last call tomorrow and asking for reviews
... there is a BP on "data enrichment" and you need to say
which value are processed and which are raw.
... hoping someone will look at this
roba: my undertanding that rdf datacuibe does not require
regular dimensions..i am looking at gridded things
billroberts: yes, may be one-dimansional eg all the towns in
australia
jonblower: th3e other thing about users is that they can go
from one type to the other but they need an entry point to
start low and help people to ramp up
... by linking between representations and processing steps
University of Reading/CoverageJSON
<Maik>
[21]https://lists.w3.org/Archives/Public/public-ceo-ld/2016May/
0000.html
[21]
https://lists.w3.org/Archives/Public/public-ceo-ld/2016May/0000.html
Maik: as on the CEO-Ld mailing list have added how to derive
new data from existing data
... also how you can tile things over any dimension in our
format
<Maik>
[22]https://github.com/Reading-eScience-Centre/coveragejson/iss
ues/29#issuecomment-219984916
[22]
https://github.com/Reading-eScience-Centre/coveragejson/issues/29#issuecomment-219984916
Maik: and how to define static subsets based on axis indices
like the cube indices
not finished yet
<billroberts> Rob's wiki page:
[23]https://www.w3.org/2015/spatial/wiki/Data_cube_for_coverage
[23] https://www.w3.org/2015/spatial/wiki/Data_cube_for_coverage
roba: joined OGC Europe on cisizen science observatories
... problem that cuts across SDW BP
... and a need to share resources
... developing a methodology for describing interoperability
profiles, wanting to test and promote SDW BPs
... particularly want datacube descriptions to model large
numbers of related datasets that realte spatially and
temporally for citizen sciences to use
... want to test ideas coming from the group
<phila> Kerry: We seem to have forgotten the linking issue
<phila> ... It seems to have gone down in the list of things we
need to deal with.
<phila> ... Are we making this up and we don't need it, or is
it really critical - which I think it is
<phila> billroberts: I think it's important
<phila> Kerry: I'm not hearing it in the discussion today
<phila> billroberts: When I was working through the reqs, it
does certainly come up in a lot of places
<phila> ... Metadata bout Coverage datasets, you need a
mechanism to add metadata
<phila> roba: That's the basis of what we'll be demonstrating.
using metadata to drive dynamic linking
<phila> ... Finding all the slices and dices through the
coverage which we see as a linking use case
roba: want to use metadata to drive dynamic linking e.g. findin
all slices and dices
<phila> Kerry: Sounds like a discovery use case to me
<phila> roba: That's a valid use of links
jonblower: but the melodies reasons are data annotation and
linking to vocabularies that describe properties
billroberts: "omn the web" is important and sometimes its a
simple as linked into a web page
<billroberts>
[24]https://www.w3.org/2015/spatial/wiki/Coverage_draft_require
ments
[24] https://www.w3.org/2015/spatial/wiki/Coverage_draft_requirements
Requirements doc: presentation and review of draft by Bill
billroberts: worked through UCR document and also BP document
... worked through those high level requirements\
... particularly coverage extracts in a web frinedly way
... some things are clearer and some are not
... q+
... will continue to tidy up and give me your thoughts...
and work through one issue at a time...
scribe: classification of requirements, started with
coverage-related and some that should be
... plus ones we brought up in meetings so far...
billroberts: ... some things we might want to pick up on
... one thing is "discovery" e.g landsat archives
... not well solved at present for non-expert community
... another issues is identifiers for coverage extracts -- is
such an identifier an aip spec for generating an extract
... or is it a thing?
... not possible to enumerate pre-prepared all possible
exptracts, so you need some kind of api,
<jonblower> got a lot of half-baked thoughts on this that we
probably don't have time to go into today...
billroberts: we also want to make sure we have a good
connection to ssn strand of work
<jonblower> (I mean I have, I wasn't minuting Bill's thoughts!)
billroberts: seveal places we see that time is of equal status
to spatial dimension
... some additional requirements not mentioned in UCR section
... also deciding what our target user groups are
... what is easy for some person is not so good for others
... planing to schedule a few of these per discussion
<phila> Kerry: I had a look at the doc and had some ideas for
little bits here and there.
<phila> ... Can I suggest that you invite people to commnet on
the doc in situ?
<phila> ... I think it's better that people edit the wiki and
attach their names/comment
<phila> ... That might work better than e-mails with bits and
pieces flying around.
<phila> billroberts: +1
billroberts: yes, please edit wiki directly, and use the "this
is a minor edit" to not send emails if appropriate
<phila> Wiki pages have a history tab so you can see who has
done what
billroberts: this is good for a frequent save strategy
... please stick you name on your comments
... BP meeting next
... any further comments?
... good stuff being done, thanks!
<billroberts> bye
Summary of Action Items
Summary of Resolutions
1. [25]approve minutes
[End of minutes]
__________________________________________________________
Received on Wednesday, 18 May 2016 15:08:38 UTC