See also: IRC log
<phila_> trackbot, start meeting
<trackbot> Meeting: Spatial Data on the Web BP Sub Group Teleconference
<trackbot> Date: 15 February 2017
<scribe> scribe:billroberts
<phila> scribe: Bill
<AndreaPerego> chair: jtandy
<phila> scribeNick: billroberts
<jtandy> minutes of last meeting: https://www.w3.org/2017/02/01-sdwbp-minutes
<Linda_> +1
PROPOSED: approve minutes of last meeting
<jtandy> +1
<ClemensPortele> +1
<LarsG> +0 (wasn't there)
0 - wasn't there
<AndreaPerego> +1
<joshlieberman> +1
<byroncinnz> +0 wasn't there
RESOLUTION: Previous minutes approved
Patent call: no issues raised
<AndreaPerego> https://www.w3.org/2015/spatial/wiki/Patent_Call
<jtandy> sprint plan https://www.w3.org/2015/spatial/wiki/Detailed_planning_BP_document
Jeremy and Linda have prioritised work items for the next sprint: Feb to Mid March
scribe: ready to release a new iteration at the Delft face to face meeting
jtandy: has added some items into
the Mid March - end April sprint as well - mainly editorial
issues. This sprint is the last opportunity for substantive
change
... Coordinate Reference Systems work for the current sprint -
Byron is working on it
byroncinnz: I've put in a pull request a couple of days ago
jtandy: thanks! will review and include it in this sprint
byroncinnz: have kept the two BPs
separate and tried to make them more distinct. Have cleaned up
language around accuracy and precision
... a lot of the issues around datum rather than CRS.
... and took out some of the more general stuff on CRS from BP3
but left it in BP17.
... I suggest moving BP3 later in the document as less
important in general than BP17
jtandy: we want to move BP17 into
the 'body' of the document. It's currently sitting in the
'Other' section
... and we can recommend WGS84 for most simple/default
cases?
byroncinnz: yes
jtandy: other blocks of tasks in the sprint plan: Dataset metadata (BP1)
<phila> Draft new WG
phila: following on from previous DCAT discussions, now preparing a new working group which will probably involve updates to DCAT. The new working group is on content negotiation by profile
jtandy: notes that we shouldn't tie ourselves to a specific version of DCAT because new things are coming
<Zakim> AndreaPerego, you wanted to mention some work planned in OGC about GeoDCAT-AP
joshlieberman: there is work on DCAT in OGC Testbed-12 and will be in Testbed-13. So the recommendation on DCAT should probably say 'keep an eye on it'
AndreaPerego: notes the OGC work on DCAT. Also there was a meeting at JRC on metadata and DCAT and possible collaboration with W3C
phila: let's discuss this in Delft to get input into next working group plans. Also note the intention to continue collaborating between OGC and W3C
jtandy: we need to put the essence of these DCAT discussions into BP1
<AndreaPerego> I can contribute.
jtandy: volunteers to do that for
us?
... thanks Andrea. But I know you have work to do on BP8. Can
anyone take a lead on BP1, to work with Andrea?
joshlieberman: I can work on BP1 with Andrea
AndreaPerego: is there a risk that the new OGC working group and W3C group will overlap and possibly coming up with competing solutions? To avoid that we should make sure we coordinate
phila: to avoid that risk, we should have a liaison
joshlieberman: it needs to be a collaboration between the metadata and geosemantics groups of OGC and we can finalise that in Delft
<joshlieberman> Yes, as of last night...
<phila> ACTION: phila to talk to OGC, Andrea etc. about liaison wrt Data Exchange WG [recorded in http://www.w3.org/2017/02/15-sdwbp-minutes.html#action01]
<trackbot> Created ACTION-267 - Talk to ogc, andrea etc. about liaison wrt data exchange wg [on Phil Archer - due 2017-02-22].
jtandy: next section is Spatial
Data vocabularies and file formats
... Andrea is working on BP8 on different representations of
geometries
AndreaPerego: I'm preparing examples to go in BP8. And trying to revise BP8 text to provide more precise guidance. I have a structure based on usage patterns (see mailing list)
<AndreaPerego> http://lists.w3.org/Archives/Public/public-sdw-wg/2017Feb/0376.html
AndreaPerego: waiting for
feedback on that
... it might be too simple, but it's a starting point. What are
the main approaches we see in practice?
... 3 options listed in the mail linked above
... Option 1 is probably best for web developers. (geometries
as literals in the data) - as long as the geometry is not too
big
... Option 2 (use HTTP URI for the geometry) is fine for LD
people, maybe less so for web developers - allows geometry to
be managed separately from other data, so more flexible
... Option 3 is often used by LD people but may be complicated
in practice. Geometry is less re-usable
... will review the pros and cons of each of those options
jtandy: please provide feedback on Andrea's idea via the mailing list
<joshlieberman_> Option 2 is best for multiple geometry options, for a choice of geometry roles or scales.
ClemensPortele: need to clarify
the context. eg GeoJSON often falls in category 3.
... and note that we agreed we would not only take an RDF
perspective. Will provide more detail via mailing list
joshlieberman_: there is a
distinction between having a geometry as a literal and having
coordinate positions as a literal
... often people represent the position as a literal but
provide other information about the geometry in a non-literal
way
... so we should make a distinction between geometry and
coordinate positions
jtandy: BP10 is another high
priority activity
... choice of vocabulary for describing spatial data
... We should provide advice people on how to make a choice of
vocab
<joshlieberman_> could we use vocabulary, encoding, serialization? file format is a blunt instrument.
jtandy: this could be a big piece
of work
... Bill, can you take ownership of BP10?
yes
jtandy: note that Bill will need assistance
<AndreaPerego> I can help - considering the relationship with BP8
jtandy: BP9
... Josh had an action to talk to Christine about the augmented
reality community
... we should start a discussion on whether to merge BP9 and
BP10
joshlieberman_: relative positioning is often about a reference system, so a bit different to spatial relationships
jtandy: so maybe closer to the CRS work that Byron has been doing?
joshlieberman_: it's about describing a position relative to another object or to a human perspective
jtandy: I know you are working on BP1 too, but could I ask you to lead BP9 as well?
joshlieberman_: yes
jtandy: I'll start a discussion
thread for whether we need a 'samePlaceAs' property
... BP14 depends on vocabulary choices. Depends to some extent
on BP10. Lars said he'd check with German colleagues about the
Beacon format
LarsG: yes, it looks like it should work fine
jtandy: I'll take the lead on
BP14
... BP16 is vague and partly covered by DWBP so I suggest
deleting and moving anything useful to BP10
... any objections to that?
<Zakim> AndreaPerego, you wanted to say that this is partially included also in BP8 - geometry complexity
AndreaPerego: I see a relation
between BP16 and BP8
... so good idea to delete
jtandy: Section 11 on how to use
the BPs will be easier once the individual BPs are more
advanced
... next block is Spatial data access and APIs
...BP11: 'convenience APIs'
... since we started the WG, a lot of what we wanted to say has
been added to DWBP
... so we need to think about how we tie things back to DWBP
and what is special about spatial data with respect to
APIs
... Can anyone on the call take the lead on moving BP11
along?
ClemensPortele volunteers to work on BP11
jtandy: Bart's work is relevant to BP11 - coordinate with Clemens on this
AndreaPerego: I can add another
example for BP11 around the CSW API
... many of our examples are more about Spatial Things than
geometries
joshlieberman: OGC APIs serve
Features rather than Geometries
... there is an aspiration to extend that but not yet an
established practice
jtandy: can we add a placeholder
for this before the Delft meeting (as no substantive changes
after that)
... minor work to do on BP12 and BP13. Could move those to next
sprint if necessary
<joshlieberman> That said, OGC services are used to reference features with geometries, that are then linked to by objects representing other feature properties (e.g. demographic info linked to population units).
jtandy: properties that change
over time. BP6 nearly complete. Linda asking Geonovum
colleagues for examples
... Editorial questions. BP2 - long discussion on mailing list
about units of measure
... suggest removing this BP unless we can identify something
specifically spatial
AndreaPerego: there is an example
of units of measures in the examples, copied from DWBP, about
spatial resolution
... example 15 is taken from Data Quality Vocabulary
... and we need to make sure we don't provide conflicting
recommendations
jtandy: will start new discussion
thread around deleting BP2
... we need to review public comments
<Zakim> phila, you wanted to ask for clarity on a couple of points in the new publiction
<phila> https://www.w3.org/TR/2017/NOTE-sdw-bp-20170216/#sotd
phila: I need help on the Status of this Document section.
jtandy: item 3 still pending. Item 4 will be done this time. Still want feedback on BP7
<joshlieberman> bye
jtandy: thanks to folks who agreed to own secions of the document
<AndreaPerego> Thanks, and bye!
thanks and bye
<ClemensPortele> thanks, bye
<BartvanLeeuwen> thx