Upload
conor
View
45
Download
0
Embed Size (px)
DESCRIPTION
GO-ESSP 2008, Seattle, September 2008. The NERC DataGrid Vocabulary Server: an operational system with distributed ontology potential. Roy Lowry British Oceanographic Data Centre. Presentation Summary. What we’ve got How to use it What’s wrong with it? What we’re doing about it - PowerPoint PPT Presentation
Citation preview
The NERC DataGrid Vocabulary Server: The NERC DataGrid Vocabulary Server: an operational system with distributed ontology potentialan operational system with distributed ontology potential
Roy Lowry
British Oceanographic Data Centre
GO-ESSP 2008, Seattle, September 2008GO-ESSP 2008, Seattle, September 2008
Presentation SummaryPresentation Summary
What we’ve got
How to use it
What’s wrong with it?
What we’re doing about it
What’s in it for CF?
What We’ve GotWhat We’ve Got Server Contents (2008-08-21)
112 public lists 122603 concepts 78123 mappings (RDF triples)
Server Usage 2008 (to 2008-08-21)
2233803 total hits (2000000 of these attributable to robots)
37462 vocabulary catalogue hits 50458 vocabulary list downloads 2085 vocabulary mapping queries
In summary a heavily populated, heavily used system
How to Use ItHow to Use ItThere are four ways to access
vocabulary content
Term and list URLs
HTTP-POX web service calls
SOAP web service calls
Interface clients
How to Use ItHow to Use It Term and list URLs
Any list may be accessed using a URL of the form http://vocab.ndg.nerc.ac.uk/list/list_id/list_version
Delivers the list, without mappings, as a SKOS XML document
Any term my be accessed using a URL of the form http://vocab.ndg.nerc.ac.uk/term/list_id/list_version/term_id
Delivers the term, including all mappings, as a SKOS XML document
How to Use ItHow to Use It<?xml version="1.0" ?>
- <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:skos="http://www.w3.org/2004/02/skos/core#" xmlns:dc="http://purl.org/dc/elements/1.1/">
- <skos:Concept rdf:about="http://vocab.ndg.nerc.ac.uk/term/P021/25/PHYC">
<skos:externalID>SDN:P021:25:PHYC</skos:externalID>
<skos:prefLabel>Phycobolin pigment concentrations in the water column</skos:prefLabel>
<skos:altLabel>WC_PhycobolPig</skos:altLabel>
<skos:definition>Concentration of phycobolin group pigments such as phycocyanin and phycoerythrin in the water column</skos:definition>
<dc:date>2008-03-11T11:56:27.531+0000</dc:date>
<skos:minorMatch rdf:resource="http://vocab.ndg.nerc.ac.uk/term/P041/4/G905" />
<skos:broadMatch rdf:resource="http://vocab.ndg.nerc.ac.uk/term/P031/8/B035" />
<skos:broadMatch rdf:resource="http://vocab.ndg.nerc.ac.uk/term/P041/4/G378" />
<skos:broadMatch rdf:resource="http://vocab.ndg.nerc.ac.uk/term/P051/0/002" />
<skos:broadMatch rdf:resource="http://vocab.ndg.nerc.ac.uk/term/P051/0/014" />
<skos:narrowMatch rdf:resource="http://vocab.ndg.nerc.ac.uk/term/P011/79/PHYCSPP4" />
</skos:Concept>
</rdf:RDF>
How to Use ItHow to Use It HTTP-POX service calls
Any API method may be invoked using an HTTP get call
Lists and terms specified in the get call parameters as URLs
Delivers an appropriate XML document (BODC-designed schema)
Documentation at http://www.bodc.ac.uk/products/web_services/vocab/methods.html
SOAP web service calls
WSDL may be found at http://vocab.ndg.nerc.ac.uk/ Same output and documentation as HTTP-POX
How to Use ItHow to Use ItInterface clients
Maris client set up for SeaDataNet at http://seadatanet.maris2.nl/v_bodc_vocab/welcome.aspx
BODC clients at http://vocab.ndg.nerc.ac.uk/ cover more vocabularies if interests extend beyond SeaDataNet
How to Use ItHow to Use ItTypical Maris client output
How to Use ItHow to Use It In SeaDataNet vocabulary terms are
included in data and metadata as URNs
These have the form:
SDN:list_id:list_version:term_id, e.g.
SDN:P021:23:TEMP SDN:P021::TEMP (for current version)
URNs resolve to URLs by simple string substitution (service to do this planned)
URLs may be used to obtain the term identifiers, labels and mappings in an XML document
What’s Wrong With It?What’s Wrong With It?
Historic version serving not implemented
Current version served whatever version is requested
Predicates (SKOS mappings) semantically limited
More suited to a thesaurus rather than an ontology
Richer set in the triple store, but cannot be served without WSDL changes
What’s Wrong With It?What’s Wrong With It?
Vocabularies not labelled with content governance authority
Mappings restricted to concepts within the server
If a vocabulary is to be included in a mapping then it must be loaded in the server
Not exactly Semantic Web!
What We’re Doing About ItWhat We’re Doing About It
Historic version serving not implemented
Necessary SQL now written so functionality will be incorporated into the next release
Predicates (SKOS mappings) semantically limited
Collaboration with Sean Bechhofer (Manchester Computer Science) to design better SKOS documents for server payload
What We’re Doing About ItWhat We’re Doing About It
Vocabularies not labelled with content governance authority
On the list of things to do for version 1.2
Mappings restricted to concepts within the server
Developing interoperable server in collaboration with ICES
Triple store structural redesign under consideration
What We’re Doing About ItWhat We’re Doing About It
In practice
V1.2 planned for the end of the year
Historic version serving
Vocabularies labelled with content governance
V2.0 date not yet fixed
Linkage to external resources
Improved SKOS document payload
What’s in it for CF?What’s in it for CF?
Currently serve Standard Names and Cell Methods
Synchronised with CF site (Alison provides update material)
Mappings maintained to SeaDataNet (BODC) and GCMD vocabularies
Support for representation of Standard Names as URLs that may be mapped and used as URNs
That’s All FolksThat’s All Folks
Thank you for your Attention
Any Questions?