dcat vocabulary resources & examples

Abstract

dcat is an RDF vocabulary for the exchange of data catalogs. Its primary purpose is the expression of government data catalogs, such as data.gov or data.gov.uk, in RDF. This is an ongoing work. We welcome feedback and discussion.

Introduction and Overview

Specification available at http://vocab.deri.ie/dcat

The following slideset on dcat was used in a presentation to the W3C e-Government Interest Group.

Prototype: Integrating four data catalogs

RDF data representation of data.gov, data.gov.uk, data.australia.gov.au, and datasf.org is available at
http://lab.linkeddata.deri.ie/govcat/. The data is published using D2R Server.

The following SPARQL query finds all datasets published by a subagency of the U.S. Department of Homeland Security:

SELECT ?title ?subagencyLabel
WHERE{
    ?dataset a dcat:Dataset;
             dct:title ?title;
             dct:publisher ?subagency.
    ?agency a foaf:Organization;
            dct:hasPart ?subagency;
            owl:sameAs  .
    ?subagency rdfs:label ?subagencyLabel.
}

Live response

Examples

  1. Representing a dataset (from data.gov)

     
      
    @prefix dcat:    <http://vocab.deri.ie/dcat#> .
    @prefix foaf:    <http://xmlns.com/foaf/0.1/> .
    @prefix dct:     <http://purl.org/dc/terms/> .
    @prefix owl:     <http://www.w3.org/2002/07/owl#> .
    @prefix xsd:     <http://www.w3.org/2001/XMLSchema#> .
    @prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
    @prefix skos:    <http://www.w3.org/2004/02/skos/core#> .
    
    :data.gov/dataset/1043
          a       dcat:Dataset ;
          rdfs:comment "The Facility Registry System (FRS) identifies facilities, sites, or places subject to environmental regulation or of environmental interest to EPA programs or delegated ..." ;
          rdfs:label "EPA FRS Facilities Combined File CSV Download for the State of Louisiana" ;
          :data_gov_catalog_data_gov_data_category_type     "Raw Data Catalog" ;
          :data_gov_catalog_specialized_data_category_designation      "Administrative" ;
          dct:accrualPeriodicity  "Continuous, updated as facility information is updated, added and changed." ;
          dct:created  "28-Sep-2009" ;
          dct:description    "The Facility Registry System (FRS) identifies facilities, sites, or places subject to environmental regulation or of environmental  interest to EPA programs or delegated state..." ;
          dct:modified "28-Sep-2009" ;
          dct:publisher :data.gov/agency/Environmental_Protection_Agency ;
          dct:spatial "Louisiana" ;
          dct:temporal "Facilities or sites currently regulated  or of interest to multiple EPA programs" ;
          dct:title "EPA FRS Facilities Combined File CSV Download for the State of Louisiana" ;
          dcat:dataDictionary <http://www.epa.gov/enviro/html/frs_demo/geospatial_data/FacilityStateFileDocumentation.pdf> ;
          dcat:dataQuality "Yes" ;
          dcat:distribution :data.gov/1043/download/2351 ;
          dcat:granularity "Coordinate Pair (latitude/longitude)" , "Facility" ;
          dcat:keyword  "facilities" , "rfs" , "rmp" , "tsd" , "aqs" , "facility registry identifier" , "npl" , "nces" , "air minor" , "major discharger" ;
          dct:references  <http://www.epa.gov/enviro/html/frs_demo/geospatial_data/FacilityStateFileDocumentation.pdf>;
          dcat:theme :data.gov/category/geography_and_environment ;
          skos:prefLabel "EPA FRS Facilities Combined File CSV Download for the State of Louisiana" ;
          foaf:homepage <http://www.data.gov/details/1043>.
    
    :data.gov/1043/download/2351
          a       dcat:Download ;
          rdfs:label "text/plain downloadable distribution of EPA FRS Facilities Combined File CSV Download for the State of Louisiana " ;
          dct:format "text/plain" ;
          dcat:accessURL <http://www.epa.gov/enviro/html/frs_demo/geospatial_data/state_files/state_combined_la.zip> ;
          dcat:size [
    	rdfs:label "8.674725 MB";
    	dcat:bytes "9096108"^^xsd:integer
          ].
      
    
  2. Representing a dataset (from data.london.gov.uk) having a direct CSV distribution

     
    
    @prefix rdfs:    <http://www.w3.org/2000/01/rdf-schema#> .
    @prefix dcat:    <http://vocab.deri.ie/dcat#> .
    @prefix foaf:    <http://xmlns.com/foaf/0.1/> .
    @prefix dct:     <http://purl.org/dc/terms/> .
    @prefix owl:     <http://www.w3.org/2002/07/owl#> .
    @prefix xsd:     <http://www.w3.org/2001/XMLSchema#> .
    @prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
    @prefix skos:    <http://www.w3.org/2004/02/skos/core#> .
    
    :data.london.gov.uk/dataset/Abandoned_Vehicles
          a       dcat:Dataset ;
          rdfs:label "Abandoned Vehicles" ;
          dct:accrualPeriodicity
                  "Annual" ;
          dct:description "Number of abandoned vehicles.To estimate missing data, the supplied data for 2007/08 has been used if at least three quarterly periods have been supplied for 2007/08.  If fewer than three quarterly periods have been supplied for 2007/08 then data from 2006/07 has been used and the average percentage increase/decrease for that region has been applied to the 2006/07 data to estimate the 2007/08 figure. This is the estimation method used for previous years' data. Ealing's 2007/08 figure is the number of abandoned vehicles of which the authority has disposed.  Previous figures for Ealing are the number of abandoned vehicles reported to the authority." ;
          dct:issued "06/05/2009" ;
          dct:references <http://www.defra.gov.uk/evidence/statistics/environment/waste/wrabanvehicles.htm> ;
          dct:spatial "Greater London" ;
          dct:title "Abandoned Vehicles" ;
          dcat:granularity "Local Authority" ;
          dcat:distribution
                  :data.london.gov.uk/dataset/Abandoned_Vehicles/csv ;
          skos:prefLabel "Abandoned Vehicles" ;
          foaf:homepage <http://data.london.gov.uk/datastore/package/abandoned-vehicles> .
    
    
    :data.london.gov.uk/dataset/Abandoned_Vehicles/csv
          a       dcat:Download ;
          rdfs:label "CSV distribution of: Abandoned Vehicles" ;
          dct:format "text/plain" ;
          dct:title "CSV distribution of: Abandoned Vehicles" ;
          dcat:accessURL <http://data.london.gov.uk/datafiles/environment/abandoned-vehicles-borough.csv> .
    
    

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