IRC log of webont on 2002-04-09

Timestamps are in UTC.

07:46:46 [RRSAgent]
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jhendler has changed the topic to: Web Ontology WG - f2f: - log -
07:47:11 [JosD]
syntax discussion...
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07:48:20 [jhendler]
RRSAgent listen
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RRSAgent, listen
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RRSAgent, bookmark
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07:49:04 [jhendler]
jhendler has changed the topic to: Web Ontology WG - f2f: - log -
07:50:04 [JosD]
pfps: if we keep RDF/XML syntax be careful not to fall inthe RDF pitfall
07:52:41 [JosD]
jimH: don't confuse syntactical and semantical pieces of the language
07:54:09 [JosD]
jeremy: decided yesterday that the base syntax is the graph syntax, *base* syntax (not presentation)
07:54:28 [JosD]
frankvh: RDFCore will tell us how to do
07:54:51 [JosD]
Path: a way of conveying a graph over the wire, that's all
07:55:25 [JosD]
massimo: RDF/XML transport syntax
07:55:55 [JosD]
jeremy: presentation syntax is out of order in this mornings's discussion
07:57:15 [jono]
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07:57:55 [JosD]
(peter proposed) decisions: syntax - RDF graph; expressive power - D + O
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07:58:08 [JosD]
peter continues his talk ...
08:00:14 [JosD]
08:01:03 [JosD]
frankvh: proposes the term (Pat corrects) --> serialization syntax
08:02:18 [JosD]
frankvh also proposes ``presentation'' syntax, normative? Jeremy doesn't care-- StevenB does care
08:03:03 [JosD]
... the issue is roundtrip
08:03:38 [JosD]
PatH: the term roundtrip has 2 meanings (interrupted by JimH)
08:04:32 [JosD]
JimH: we will return to this point today (after the coffee break)
08:04:49 [JosD]
Peter continues again... RDF compatibility\
08:05:18 [JosD]
08:06:16 [JosD]
(further proposed decisions) RDF MT; Inferences (what follows from what)
08:07:25 [JosD]
Jeremy: entailment to clarify the meaning
08:08:51 [JosD]
jonathanB: concerned about violation of intuitions...
08:16:42 [JosD]
Peter & Pat believe there is a way to go...
08:17:07 [JosD]
there is a diagonal line asserted / darh
08:17:36 [JosD]
i.e. John loves Mary / D + O syntax
08:18:21 [JosD]
i.e. constrain interptretaions / mentions like D + O syntax
08:22:16 [JosD]
PatH: RDF is a vocabulary defining toolkit
08:24:21 [JosD]
frankvh: 2 things: *language* conformance level 0 versus vocabulary defining toolkit
08:26:07 [JosD]
Ian: the whole trouble is that it is doing these 2 things
08:27:23 [JosD]
JimH is again interrupting the discussion
08:28:15 [JosD]
JimH takes ACTION (for CG) : relationship with RDFS has to become very clear
08:29:06 [JosD]
Jimh: RDF(S) has to mean the same thing...
08:30:07 [JosD]
Guus: identify the part of RDFS that may act as conformance level 0
08:30:57 [JosD]
PatH: yes we can (it's not vocabulary, but certain combination patterns (if I understood that well???))
08:32:12 [JosD]
PatH: maybe, maybe (Peter: be lord and master of the universe.......)
08:32:59 [JosD]
Peter continues... how to make the distinction (betweeen asserted and unasserted)
08:34:29 [JosD]
one syntactical way: XML -- RDF document (asserted ) / XML Schema -- OWL document (unasserted)
08:34:55 [JosD]
is it nice???
08:37:37 [JosD]
all the definition stuff goes in the unasserted side
08:38:08 [JosD]
they are dard for RDF but they have a meaning
08:39:20 [JosD]
Jeremy wonders about his proposal (the sollipsitic one)
08:40:46 [JosD]
Jeremy: you have to *assert* the existence of the class
08:43:40 [JosD]
Peter: ontologies *refer* to other ontologies, or you merge them
08:45:15 [JosD]
Guus: conclusions: issue is RDFS clarification
08:46:38 [JosD]
2. the proposed dark triple proposal is *not* affecting RDF core (question)
08:48:38 [JosD]
PatH: 1. WebOnt definitely needs dark triples
08:49:42 [JosD]
PatH 2. several proposals are possible, some are affecting RDFCore
08:51:13 [JosD]
e.g. Jonathan's proposal recursive rdf:RDF elements to represent contexts
08:54:12 [JosD]
Guus: there is an urgent timing issue involved!!!
08:55:54 [JosD]
Jeremy is showing what current parsers do...
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09:31:31 [JosD]
Guus: propose synthesis discussion
09:32:20 [JosD]
RDFCore provides us a serialization syntax
09:33:04 [JosD]
let's use RDF/XML
09:34:38 [JosD]
(the term used by RDFCore)
09:35:12 [JosD]
... and use that to serialize OWL level1 and OWL level 2
09:37:25 [JosD]
RDFCore: RDF serialization syntax -> RDF graph
09:38:20 [JosD]
WebOnt requirements -- 2 issues 1) LIST 2) DARK TRIPLES
09:42:12 [JosD]
JimH: proposed action: PeterPS + FrankVH + JeremyC write down a paragraph for RDFCore w.r.t. these issues
09:42:42 [JosD]
(will happen today)
09:43:33 [JosD]
JimH: if we have a preference, we should say that
09:44:26 [JosD]
other side if Guus's picture: OWL presentation syntax
09:50:18 [JosD]
issues: 1) readablility 2) level of roundtripping (same presentation syntax/ other PS) 3) preferred one (normative?)
09:52:30 [JosD]
(discuss again the trick to keep a pointer to the original RDF/XML document)
09:53:32 [JosD]
Jeremy: roudtripping argument is spurious, issue is keeping the original presentation syntax
09:54:51 [JosD]
jb: in general rt in not solvable, so keep original...
09:56:40 [JosD]
Enrico: good requirement would be to give back a piece which is semantically equivalent
10:02:48 [JosD]
StephenB: you can't have a requirement of rt (e.g. for something that came in as serialization syntax)
10:04:19 [JosD]
frankvh: giving example of Protege tool (presentation syntax), but it doesn't work across tools...
10:05:47 [JosD]
JimH: all of us are interoperating if we don't have a strong presentation syntax
10:06:20 [JosD]
... dozens of different ways to do this
10:08:18 [JosD]
Ora: what are the characteristics we are interested in to be preserved?
10:09:14 [JosD]
FrankVH is really concerned about usability
10:10:40 [JosD]
Guus: group definitions + editable in something like emacs
10:11:39 [JosD]
Enrico: requrement is slightly more readable syntax
10:12:21 [JosD]
MikeD: worry is wether tools should export both
10:12:53 [JosD]
StephenB: not mandate, keep as local thing
10:13:41 [JosD]
Jeremy remarks that there is no common agreed format for word processors
10:15:15 [JosD]
JimH: what GUIDE can do is work out this stuff in N3, UML etc
10:16:20 [JosD]
... don't give it the level the AC (advisory commitee) has to approved
10:19:51 [JosD]
Ora: write down an ontology for the description of the things to be preserved
10:21:47 [JosD]
Guus: 2 forms: readable text form (e.g. N3) and graphical form (e.g. UML)
10:23:15 [JosD]
Enrico: user want 1 syntax which is easy to understand
10:24:40 [JosD]
MikeD: finds the graph notation very useful (even to explain derivations)
10:28:00 [JosD]
JimH: being able to interoperate is crucial but it's fine to have several ps's in the nn appendices
10:29:41 [JosD]
(ps == presentation syntax; nn == non normative)
10:32:28 [JosD]
jb: nn because of all syntactical guarantees; not part of the formal language definition
10:34:03 [JosD]
StephenB: explains what it means to be NN using MathML example
10:34:54 [JosD]
Massimo: explains further along the lines of the W3C process
10:35:38 [JosD]
... it is completely optional, it *might* become a de facto practice
10:37:30 [JosD]
--------------------------------- END Of SESSION / LUNCH BREAK
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11:58:45 [JosD]
discussing entailment testcase :Peter a :Student, :Employee . |= :Peter a [ owl:intersectionOf ( :Student :Employee ) ] .
11:59:39 [jhendler]
question raised: does a user (of OWL) need to know this exists?
12:00:46 [JosD]
Jeremy would have to add [ owl:intersectionOf ( :Student :Employee ) ] . at LHS
12:00:56 [jhendler]
that is - for dark triples would the rdf/xml need to include dark - answer, yes.
12:01:58 [jhendler]
if you do it via "solipsistic" logic, the user doesn't need to know
12:02:07 [jhendler]
however, there may be other problems.
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12:23:10 [JosD]
strawpoll: 12 people support dark triple proposal; 3 support solipsistic proposal; 6 abstain
12:25:35 [JosD]
finding agreement on the proposed paragraphs...
12:29:50 [JosD]
1 paragraph is request; other paragraphs are suggestions
12:37:08 [JosD]
volunteers from this group to join conversation with RDFCore: Jeremy, Pat, Peter, Jos, Massimo
12:37:29 [JosD]
+ Jonathan (Borden)
12:38:57 [JosD]
unanimous agreement to send message to RDFCore
12:40:23 [JosD]
Action to the chairs Jim and Guus to report this issue to the SWCG
12:42:26 [JosD]
======= Ora and "Thoughts about the Guide"
12:43:53 [JosD]
(this is a summary of their break-out session)
12:54:38 [JosD]
======= discussing (again) D+O Appendix: Index of all language elements
12:55:39 [jhendler]
12:56:26 [jhendler]
12:56:45 [JosD]
? * cardinality
12:57:58 [JosD]
actually should be ? * cardinality
12:59:05 [JosD]
oops 1/2 * cardinality
13:00:00 [JosD]
decided taking out all the ...Q things
13:01:23 [JosD]
R == rdf(s) 1 == level 1 2 == level 2
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13:03:48 [JosD]
DatatypeProperty, DatatypeRestriction, Datatype value are in 1
13:04:58 [JosD]
Disjoint is in 1
13:07:18 [JosD]
disjointWith is X (i.e. gone)
13:08:10 [JosD]
arrow is, it goes to the issue list, cardinality, Class, equivalentTo
13:09:44 [JosD]
hasClass, hasValue level 1
13:10:49 [JosD]
imports is an X
13:12:04 [JosD]
oops, imports is an -> (issue list)
13:13:22 [JosD]
intersectionOf, inverseOf also issues
13:16:13 [JosD]
ObjectClass, ObjctProperty, ObjectRestriction are in 1 (however there is the issue Datatype disjoint from Class)
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13:16:46 [JosD]
oneOf, onProperty, Ontology are in 1
13:17:46 [JosD]
Property, range, subClassOf, subPropertyOf fall in R(DF)
13:19:00 [JosD]
UnambiguousProperty (new proposed name UniqueIdentifyingProperty) level 1
13:20:57 [JosD]
UniqueProperty (new proposed name SinglevaluedProperty) level 1
13:22:05 [JosD]
version level 1
13:25:41 [JosD]
---------------------------------------time for a break....
13:29:33 [JosD]
remarkable thing: UnionOf is the only level 2
13:29:57 [JosD]
let's talk about that during the coffee break (10 min)
13:44:06 [JosD]
rdf issue list
13:45:42 [JosD]
similar Issues list in DAML:
13:45:55 [JosD]
-> 1/2 cardinality
13:46:09 [JosD]
-> R Class
13:46:22 [JosD]
-> ? equivalentTo
13:46:33 [JosD]
-> 1 imports
13:46:47 [JosD]
-> * intersectionOf
13:47:01 [JosD]
-> * inverseOf
13:47:16 [JosD]
-> 2 unionOf
13:47:30 [JosD]
-> 1 UniqueProperty
13:47:51 [JosD]
Where does Defined Class go?
13:48:23 [JosD]
Where do complementOf, UnionOf, etc. go?
13:49:10 [JosD]
Guus: propose to move all constructs using unnamed classes to go to level 2
13:52:33 [JosD]
PatH: existential quantifiers are already in RDF
13:54:50 [JosD]
Guus: make (some) people familiar with notion of implicit class names
13:55:36 [JosD]
PatH: not understanding the distinction
13:58:23 [JosD]
Jeremy drawing a graph of the example :John a _:1 . _:1 a rdfs:Class; owl:intersectionOf ( :Student :Employee ) .
14:00:05 [JosD]
JimH: group seems to be in favor of 1/2, but go back to drawing board to draw the borderline
14:03:57 [JosD]
Jeremy: keep 1/2 and ask LANG new proposal ==> 12 people
14:04:32 [JosD]
... versus 1 language ==> 6 people
14:08:19 [JosD]
ACTION: revisit new level 1/2 proposal by MikeD, EnricoM, ZivH, RaphaelV, IanH and FrankVH
14:09:48 [JosD]
(Jim's pinguin example...)
14:14:14 [JosD]
RESOLUTIONS: The meaning of an OWL document is conveyed in the RDF graph ==> ALL in favour, NO opposed
14:25:22 [JosD]
RESOLUTION: All RDF/XML documents that are equivalent under the RDF REC are equivalent OWL exchange documents ==> 14 in favor -- 3 opposed
14:33:05 [JosD]
RESOLUTION: The exchange language for OWL is RDF/XML ==> 16 in favour
14:41:56 [JosD]
RESOLUTION: We intend to produce non-normative presentation syntaxes and their mapping to the exchange syntax ==> 16 in favour -- 1 opposed
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14:48:39 [DeborahMc]
good morning
14:50:51 [JosD]
RESOLUTION: The preference of the WG is to produce at least one XML and one frame presentation syntax ==> 11 in favour -- 2 opposed
14:51:52 [JosD]
logs are at
14:52:28 [JosD]
the last part is about the resolutions
14:53:23 [JosD]
======= how to move forward till next f2f
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14:55:55 [heflin]
I just joined the telecon. Sorry I'm late.
14:56:29 [JosD]
FrankVH gives some explanation about these resolutions
14:59:05 [JosD]
JimH: a set of issues will be collected, then ask the group, then go to REAL issue list
15:00:29 [JosD]
JimH: issue drive process -- ACTION chairs + MikeS
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15:02:34 [JosD]
DebMG will join the "revisit new level 1/2 proposal" group
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15:06:33 [JosD]
discussion about "what should be preserved?"
15:09:16 [JosD]
e.g. order, grouping, etc. (within and between presentation syntaxes)
15:11:53 [JosD]
NickG: matter of toolbuilders + JimH: to allow some metadata format to describe that
15:17:31 [JosD]
discussion about the proposed schedule: 5 in favor -- 0 abstain
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15:19:24 [jhendler]
Meeting is officially ended w/respect to rsolutions - conversation continures
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