# Presentation: 215433

## The NERC DataGrid Vocabulary Server: an operational system with distributed ontology potential

**Roy Lowry**
**British Oceanographic Data Centre**

**GO-ESSP 2008, Seattle, September 2008**

## Presentation 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 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 It

**There 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 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 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 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://](http://www.bodc.ac.uk/products/web_services/vocab/methods.html)__[www.bodc.ac.uk/products/web_services/vocab/methods.html](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/](http://vocab.ndg.nerc.ac.uk/)**_
**Same output and documentation as HTTP-POX **

## How to Use It

**Interface clients**
**Maris client set up for SeaDataNet at **_**[http://seadatanet.maris2.nl/v_bodc_vocab/welcome.aspx](http://seadatanet.maris2.nl/v_bodc_vocab/welcome.aspx)**_
**BODC clients at **_**[http://vocab.ndg.nerc.ac.uk/](http://vocab.ndg.nerc.ac.uk/)**_** cover more vocabularies if interests extend beyond SeaDataNet**

## How to Use It

**Typical Maris client output **

## How 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?

**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?

**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 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 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 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?

**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 Folks

**Thank you for your Attention**
**Any Questions?**