Managing dynamic ontologies that can't be allowed to change
UK Ontology Network
Aston University
24 April 2014
Persistence at W3C
Pledge (1/2)
- The hosts will ensure that persistent resources continue to be
available throughout the life of the Consortium;
- Where a persistent resource is modified, a change history will be
archived though the archive will not necessarily be available
publicly;
- Should the W3C be disbanded, then any Web site will be granted the
right to make a copy (at a different URI) of all public persistent
resources so long as they are not modified and are preserved in their
entirety and made available free of charge, and provided the same
persistence policy is applied to these "historical mirrors." In such
event, the original http://www.w3.org web site will be handed over for
management to another organization only if that organization pledges to
this policy or one considered more persistent.
Persistence at W3C
Pledge (2/2)
As of this note, persistent resources include:
- The home page "http://www.w3.org/";
- Those which start "http://www.w3.org/" immediately followed by four
decimal digits;
- Those which start "http://www.w3.org/TR/" immediately followed by four
decimal digits;
- Those which start with "http://www.w3.org/ns/".
Written by TimBL in 1999 and unchanged since, see http://www.w3.org/Consortium/Persistence.html.
The 10 DOs and DON'Ts for persistent URIs
Do
- Follow the pattern
- e.g. http://{domain}/{type}/{concept}/{reference}
- Re-use existing identifiers
- e.g. http://education.data.gov.uk/id/school/123457
- Link multiple representations
- e.g. http://data.example.org/doc/foo/bar.rdf
- e.g. http://data.example.org/doc/foo/bar.html
- Implement 303 redirects for real-world objects
- e.g. http://www.example.com/id/alice_brown
- e.g. http://www.example.com/doc/alice_brown
- Use a dedicated service
- i.e. independent of the data originator
10 rules
for persistent URIs
Don't
- Avoid stating ownership
- e.g. http://education.data.gov.uk/ministryofeducation/id/school/123456
- Avoid version numbers
- e.g. http://education.data.gov.uk/doc/school/v01/123456
- Avoid using auto-increment
- e.g. http://education.data.gov.uk/id/school/123456
- e.g. http://education.data.gov.uk/id/school/123457
- Avoid query strings
- e.g. http://education.data.gov.uk/doc/school?id=123456
- Avoid file extensions
- http://education.data.gov.uk/doc/schools/123456.csv
See the Study on Persistent URIs.
Persistent Terms
Once published:
- terms must not be deleted;
- must not be redfined.
But
- they may be deprecated;
- their definitions may be clarified;
- usage notes may be added;
- their labels and definitions may be localised.
Persistent Standards
Small Vocabularies in static files
Hosted on w3.org
Hosted elsewhere
schema.org (large with custom infrastructure)
Terms are all http://schema.org/Foo, e.g. http://schema.org/Person
Every terms resolves to an individual HTML page
Deprecated terms
…
dcat:bytes a rdf:Property, owl:DatatypeProperty;
rdfs:isDefinedBy dcat:;
rdfs:label "size in bytes (Deprecated)";
rdfs:comment "describe size of resource in bytes. This term has been deprecated";
rdfs:domain dcat:Distribution;
owl:deprecated true ;
rdfs:range xsd:integer .
Management vehicle
W3C Community Groups
- Anyone can join (although employees of W3C member companies will need management approval)
- Open forum for discussion
- Easy to ask for a w3.org/ns namespace
- Open to ideas on tooling
See http://www.w3.org/community/
Now, soon and quite possibly later
Now, soon and quite possibly later
The W3C Data Activity now
Soon and quite possibly later
- Ontology development tools - room for a lot more
- RDF Data Shapes
- Geospatial Data on the Web (with OGC)
- Sharing starting conditions, analysis algorithms, and outcomes??
Basic question
How can we help more?
Basic question
How can we help more?
