|
Hi Bob,
I would be glad if you could do that (introduce me to your colleagues). That is the main reason I decided to contact this group before defining things on my own. My main goal is to actually leverage on what the community has already done with respect to linking data, and more specifically, to "Government Linked Data".
Thanks, Rommel
-- Dr. Rommel N. Carvalho
Postdoctoral Research Associate
2012/3/15 Bob Schloss <rschloss@xxxxxxxxxx>
Hi Rommel,
There is a working
group at the World Wide Web Consortium working on "Government Linked
Data". If you want to understand more about what they are currently
working on, I would be happy to introduce you to some colleagues who are
participating. I think their draft specifications will start to be
circulated in a few months (but I'm not certain about their timeline).
There are also a
lot of grass-roots efforts, some pushed by groups like Civic Commons ,
some collaborative works by universities, governments and the IT community
(one that I happen to know about is http://DubLinked.ie
for the governments around Dublin Ireland) , so you may be able to levarage
practical solutions that have started to emerge around the world in the
last few years.
Regards,
Bob Schloss
STSM; Smarter Planet Sustainability: Scalable Information Infrastructure
IBM Thomas J Watson Research Center
From:
Rommel Carvalho <rommel.carvalho@xxxxxxxxx>
To:
Ontology Summit 2012
discussion <ontology-summit@xxxxxxxxxxxxxxxx>
Date:
03/15/2012 12:59 PM
Subject:
Re: [ontology-summit]
Standard way to define URIs in ontologies for the SW
Sent by:
ontology-summit-bounces@xxxxxxxxxxxxxxxx
Thanks, Simon! This was exactly what I was looking for!
It helps a lot! :-)
Best,
Rommel
--
Dr. Rommel N. Carvalho
Postdoctoral Research Associate
C4I Center / GMU
http://mason.gmu.edu/~rcarvalh
2012/3/15 Simon Spero <sesuncedu@xxxxxxxxx>
On Thu, Mar 15, 2012 at 10:57 AM, Rommel Carvalho <rommel.carvalho@xxxxxxxxx>
wrote:
One of the things we will address in these
documents is how to define the URI for the different ontologies we will
be creating. I was hoping you could point me to the right direction on
where I can find information on best practices to define URIs for ontologies
in the Semantic Web. Is there some kind of standard for this?
The following W3 publication offesr some relevant guide-lines:
Best
Practice Recipes for Publishing RDF Vocabularies (http://www.w3.org/TR/2008/NOTE-swbp-vocab-pub-20080828/
- W3 NOTE)
There are also some rules of thumb - http://www.w3.org/wiki/User:Rcygania2/RulesOfThumb#Namespace_URIs
There are a few choices to be made that depend on technical
and administrative factors.
1) The hostname part of the URI: Do you want to
use PURLs (purl.org),
do you wish to use existing domain names, or do you want to create a new
domain to host the vocabularies? Do you want to have a central site
hosting all vocabularies; do you want to have a central site that redirects
to hosts managed by individual departments/agencies, etc?
2) The path name for the vocabulary: There are a
couple of conventions:
Note
that in both of the examples, the namespace contains what at first glance
appears to be timestamp or version information; however in both of these
cases, the ontology version has changed a great deal, but the namespace
has remained constant. The FOAF spec notes:
Much of FOAF now is considered stable. Each release of
this specification document has an incrementally increased version number,
even while the technical namespace ID remains fixed and includes the original
value of "0.1". It long ago became impractical to update the
namespace URI without causing huge disruption to both producers and consumers
of FOAF data. We are left with the digits "0.1" in our URI. This
stands as a warning to all those who might embed metadata in their vocabulary
identifiers.
This approach requires the semantics of existing terms
in the namespace to remain downwards compatible. If the meaning of
a term changes in a way that is not downwards compatible with extant usage
then a new namespace is needed. This roughly corresponds to a new
major version in a software API.
Just chatting now with Dan, he now favours only
adding a version id if a second version is needed. This seems reasonable
enough, though from a human factors point of view, there is a danger of
accidentally referring to the older version due to accidentally omitting
the version part of the namespace.
If a new namespace is needed, then terms that are (absolute
LL) identical can be declared 'sameas' and 'equivalent<Foo>'
in the new namespace, allowing for partial backwards compatibility.
3) Hash or Slash.
If the vocabulary is small, then the namespace can be
declared using a '#' after the ontology name, making term names relative.
This allows the whole document to be fetched in a single transaction, and
verified with a single cache check. SKOS uses a # namespace.
If the vocabulary is very large, then a '/' namespace
is better; only terms that are needed will be fetched, and only modified
terms need to be invalidated in a cache. Since vocabulary items can be
defined in documents other than those directly matching the namespace URI,
you can include closely associated term definitions in individual documents
to reduce network latency.
It is possible to mix and match the approaches.
Hope this helps
Simon
_________________________________________________________________
Msg Archives: http://ontolog.cim3.net/forum/ontology-summit/
Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontology-summit/
Unsubscribe: mailto:ontology-summit-leave@xxxxxxxxxxxxxxxx
Community Files: http://ontolog.cim3.net/file/work/OntologySummit2012/
Community Wiki: http://ontolog.cim3.net/cgi-bin/wiki.pl?OntologySummit2012
Community Portal: http://ontolog.cim3.net/wiki/
_________________________________________________________________
Msg Archives: http://ontolog.cim3.net/forum/ontology-summit/
Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontology-summit/
Unsubscribe: mailto:ontology-summit-leave@xxxxxxxxxxxxxxxx
Community Files: http://ontolog.cim3.net/file/work/OntologySummit2012/
Community Wiki: http://ontolog.cim3.net/cgi-bin/wiki.pl?OntologySummit2012
Community Portal: http://ontolog.cim3.net/wiki/
_________________________________________________________________
Msg Archives: http://ontolog.cim3.net/forum/ontology-summit/
Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontology-summit/
Unsubscribe: mailto:ontology-summit-leave@xxxxxxxxxxxxxxxx
Community Files: http://ontolog.cim3.net/file/work/OntologySummit2012/
Community Wiki: http://ontolog.cim3.net/cgi-bin/wiki.pl?OntologySummit2012
Community Portal: http://ontolog.cim3.net/wiki/ (01)
|
