The document discusses the Data Catalog (DCAT) vocabulary, which is being developed by the W3C Government Linked Data Working Group to facilitate interoperability between data catalogs published on the web. It provides examples of how DCAT can be used to enable advanced queries across multiple catalogs and describes implementations of DCAT by several government organizations to publish metadata about their datasets.

1. Digital Enterprise Research Institute www.deri.ie
Dcat
Machine Accessible Catalogue
Fadi Maali
Copyright 2011 Digital Enterprise Research Institute. All rights reserved.
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2. Dataset
Digital Enterprise Research Institute www.deri.ie
http://www.dublinked.ie/datastore/index.php
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3. Machine Accessible
Digital Enterprise Research Institute www.deri.ie
https://scraperwiki.com/scrapers/dublinked_datasets/
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4. Eg1 – Federated Catalog
Digital Enterprise Research Institute www.deri.ie
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5. Eg2 - Advanced queries
against/across catalogs
Digital Enterprise Research Institute www.deri.ie
 All CSV datasets that is published by the city council and
was updated in the last week
 All XML datasets that are about education and published
by a local authority
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6. Dcat
Digital Enterprise Research Institute www.deri.ie
http://dvcs.w3.org/hg/gld/raw-file/default/dcat/index.html
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7. Status of dcat
Digital Enterprise Research Institute www.deri.ie
 Being worked on at the W3C Government Linked Data
Working Group
 Will (hopefully) be put on the W3C standardization track
 Goal: when someone wants to publish catalogue data in
RDF, dcat will be his choice  more adoption  more
usefulness  more adoption  more usefulness …
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8. Who is using dcat?
Digital Enterprise Research Institute www.deri.ie
 data.gov.uk (RDFa)
http://data.gov.uk/dataset/financial-transactions-data-the-
pennine-acute-hosiptals-nhs-trust-0
 semantic.ckan.net (SPARQL endpoint)
http://semantic.ckan.net/snorql/
 Publicdata.eu (RDFa, SPARQL)
http://publicdata.eu/dataset/02-bve-onderwijspersoneel-
in-fte--ministerie-van-ocw
 Barcelona, Gijón, Catalonia, Balearic Islands, Saragossa
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9. Dcat as RDFa (1/2)
Digital Enterprise Research Institute www.deri.ie
<div class=“metadata”
<div class=“metadata” >
about="http://www.dublinked.ie/dataset/126" typeof="dcat:Dataset" >
<div class="metadata-line">
<div class="metadata-line">
<div class="metadata-tag">Title</div>
<div class="metadata-tag">Title</div>
<div class="metadata-content">Objective_A1</div>
</div> class="metadata-content“ property="dct:title">Objective_A1</div>
<div
</div>
</div>
</div>
http://www.dublinked.ie/datastore/metadata031.php
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10. Dcat as RDFa (2/2)
Digital Enterprise Research Institute www.deri.ie
<div class="metadata-line">
<div class="metadata-tag">Download Links</div>
<div class="metadata-line">
<div class="metadata-content“ rel="dcat:distribution" >
<div typeof="dcat:Distribution" rel="dcat:accessURL"
<a class="metadata-tag">Download Links</div>
<divproperty="dct:format" content=“shx"
class="metadata-content“>
<ahref="http://www.dublinked.ie/...filename...1246.shx"></a>
href="http://www.dublinked.ie/...filename...1246.shx"></a>
</div>
</div>
</div>
</div>
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11. Distilling
Digital Enterprise Research Institute www.deri.ie
http://www.w3.org/2007/08/pyRdfa/
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