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<!DOCTYPE html>
<html>
<head>
<title>Data Catalog Vocabulary (DCAT) - revised edition</title>
<meta content="text/html; charset=utf-8" http-equiv="content-type" />
<meta content="width=device-width,initial-scale=1" name="viewport" />
<script class="remove" src="https://www.w3.org/Tools/respec/respec-w3c-common"></script>
<script class="remove" src="config.js"></script>
</head>
<body>
<section id="abstract">
<p>DCAT is an RDF vocabulary designed to facilitate interoperability between data catalogs published on the Web. This document defines the schema and provides examples for its use.</p>
<p>By using DCAT to describe datasets in data catalogs, publishers are using a standard model and vocabulary that facilitates the consumption and aggregation of metadata from multiple catalogs,
and in doing so can increase the discoverability of datasets. It also makes it possible to have a decentralized approach to publishing data catalogs and makes federated search for datasets across catalogs in multiple sites possible using the same query mechanism and structure. Aggregated DCAT metadata can serve as a manifest file as part of the digital preservation process.</p>
<p style="text-align: center;">The namespace for DCAT terms is <code>http://www.w3.org/ns/dcat#</code></p>
<p style="text-align: center;">The suggested prefix for the DCAT namespace is <code>dcat</code></p>
<p style="text-align: center;">The (revised) DCAT vocabulary is available <a href="https://raw.githubusercontent.com/w3c/dxwg/gh-pages/dcat/rdf/dcat.ttl">here</a>.</p>
</section>
<section id="sotd">
<h3>DCAT Family of Documents</h3>
<p>
This document is part of the output of the Dataset Exchange Working Group (DXWG).
All documents from the group are listed here.
</p>
<h4>DCAT documents</h4>
<p>
The DCAT documents are about the revised Data Catalog Vocabulary.
</p>
<ul>
<li>[VOCAB-DCAT] (Recommendation) - this document, description of the DCAT RDF vocabulary</li>
</ul>
<h4>Profiling documents</h4>
<p>
These documents give guidance on profiling. Some of the documents are general while some are technology-specific.
Please consult the Profile Guidance [[PROF-GUIDE]] document for an overview of all profiling documents. It is the
recommended starting point.
</p>
<ul>
<li>[[PROF-GUIDE]] (Recommendation) - the top-level general profiling guidance document giving an overview of all other documents</li>
<li>[[PROF-CONNEG]] (Recommendation) - Specific guidance on how to negotiate for Internet resource content using profiles</li>
<li>[[PROF-IETF]] (<a href="http://www.ietf.org">IETF</a> <a href="http://www.ietf.org/standards/ids/">Internet-Draft</a>) - HTTP Headers for HTTP content negotiation by profile</li>
</ul>
<h3>DCAT history</h3>
<p>The original DCAT vocabulary (originally hosted at http://vocab.deri.ie/dcat) was developed at the Digital Enterprise Research Institute (DERI), refined by the <a href="http://www.w3.org/egov/">eGov Interest Group</a>, and then finally standardized in 2014 [[VOCAB-DCAT-20140116]] by the <a href="http://www.w3.org/2011/gld/">Government Linked Data (GLD)</a> Working Group.</p>
<p>This revised version of DCAT was developed by the <a href="https://www.w3.org/2017/dxwg/">Dataset Exchange Working Group</a> in response to a new set of Use Cases and Requirements [[DCAT-UCR]] submitted on the basis of experience with the DCAT vocabulary from the time of the original version, and new applications not originally considered.</p>
<h3>External terms</h3>
<p>DCAT incorporates terms from pre-existing vocabularies where stable terms with appropriate meanings could be found, such as foaf:homepage and dct:title. Informal summary definitions of the externally-defined terms are included here for convenience, while authoritative definitions are available in the normative references. Changes to definitions in the references, if any, supersede the summaries given in this specification. Note that conformance to DCAT (Section 4) concerns usage of only the terms in the DCAT namespace itself, so possible changes to the external definitions will not affect the conformance of DCAT implementations.</p>
<h3>Please send comments</h3>
</section>
<section id="introduction" class="informative">
<h2>Introduction</h2>
<p class="note">From DCAT 2014 [[!VOCAB-DCAT-20140116]]</p>
<p>Data can come in many formats, ranging from spreadsheets, through XML and RDF, to various speciality formats. DCAT does not make any assumptions about the serialisation format of the datasets described in a catalog. Other, complementary vocabularies <em title="MAY" class="rfc2119">MAY</em> be used together with DCAT to provide more detailed format-specific information. For example, properties from the VoID vocabulary [[VOID]] can be used to express various statistics about a DCAT-described dataset if that dataset is in RDF format.</p>
<p>This document does not prescribe any particular method of deploying data expressed in DCAT. DCAT is applicable in many contexts including RDF accessible via SPARQL endpoints, embedded in HTML pages as RDFa, or serialized as e.g. RDF/XML or Turtle. The examples in this document use Turtle simply because of Turtle's readability.</p>
</section>
<section id="motivation" class="informative"><h2>Motivation for change</h2>
<p>The original Recommendation [[VOCAB-DCAT-20140116]], published in January 2014, provided the basic framework for describing datasets. Importantly, it made the distinction between a dataset as an abstract idea and a distribution as a manifestation of the dataset. Although DCAT has been widely adopted, it has became clear that the original specification lacked a number of essential features that were added either through application profiles, such as the European Commission's DCAT-AP [[DCAT-AP]], or the development of larger vocabularies that, to a greater or lesser extent, built upon the base standard, such as the Healthcare and Life Sciences Community Profile [[HCLS-Dataset]], the Data Tag Suite [[DATS]] and more. This version of DCAT has been developed to address the specific shortcomings that have come to light through the experiences of different communities, the aim being, of course, to improve interoperability between the outputs of these larger vocabularies.</p>
</section>
<section id="namespaces-1">
<h2 >Namespaces</h2>
<p>The namespace for DCAT is <code>http://www.w3.org/ns/dcat#</code>.
However, it can be noted that DCAT makes extensive use of terms from other vocabularies, in particular Dublin Core [[DCTERMS]].
DCAT itself defines a minimal set of classes and properties of its own.
A full set of namespaces and prefixes used in this document is shown in the table below.</p>
<table id="namespaces">
<thead><tr><th>Prefix</th><th>Namespace</th></tr></thead>
<tbody>
<tr><td>dcat</td><td>http://www.w3.org/ns/dcat#</td></tr>
<tr><td>dct</td><td>http://purl.org/dc/terms/</td></tr>
<tr><td>dctype</td><td>http://purl.org/dc/dcmitype/</td></tr>
<tr><td>dqv</td><td>http://www.w3.org/ns/dqv#</td></tr>
<tr><td>foaf</td><td>http://xmlns.com/foaf/0.1/</td></tr>
<tr><td>owl</td><td>http://www.w3.org/2002/07/owl#</td></tr>
<tr><td>prov</td><td>http://www.w3.org/ns/prov#</td></tr>
<tr><td>rdf</td><td>http://www.w3.org/1999/02/22-rdf-syntax-ns#</td></tr>
<tr><td>rdfs</td><td>http://www.w3.org/2000/01/rdf-schema#</td></tr>
<tr><td>skos</td><td>http://www.w3.org/2004/02/skos/core#</td></tr>
<tr><td>vcard</td><td>http://www.w3.org/2006/vcard/ns#</td></tr>
<tr><td>xsd</td><td>http://www.w3.org/2001/XMLSchema#</td></tr>
</tbody>
</table>
</section>
<section id="conformance">
<p class="note">Modified from DCAT 2014 [[VOCAB-DCAT-20140116]]</p>
<p>A data catalog conforms to DCAT if:</p>
<ul>
<li> Access to data is organized into datasets, distributions, and data-services. </li>
<li> An RDF description of the catalog itself and its datasets, distributions, and data-services is available (but the choice of
RDF syntaxes, access protocols, and access policies is not mandated by this specification).</li>
<li> The contents of all metadata fields that are held in the catalog, and that contain data about the catalog itself and its datasets, distributions, and data-services, are included in this RDF description, expressed using the appropriate classes and properties from DCAT, except where no such class or property exists.</li>
<li> All classes and properties defined in DCAT are used in a way consistent with the semantics declared in this specification.</li>
<li>DCAT-compliant catalogs <em title="MAY" class="rfc2119">MAY</em> include additional non-DCAT metadata fields and additional RDF data in the catalog's RDF description.</li>
</ul>
<p>
A <strong>DCAT profile</strong> is a specification for data catalogs that adds additional constraints to DCAT. A data catalog that conforms to the profile also conforms to DCAT. Additional constraints in a profile <em title="MAY" class="rfc2119">MAY</em> include:
</p>
<ul>
<li> Cardinality constraints, including a minimum set of required metadata fields </li>
<li> Sub-classes and sub-properties of the standard DCAT classes and properties</li>
<li> Classes and properties for additional metadata fields not covered in DCAT</li>
<li> Controlled vocabularies or URI sets as acceptable values for properties</li>
<li> Requirements for specific access mechanisms (RDF syntaxes, protocols) to the catalog's RDF description</li>
</ul>
</section>
<section id="vocabulary-overview" class="informative">
<h2>Vocabulary overview</h2>
<p class="note">From DCAT 2014 [[VOCAB-DCAT-20140116]] except as noted</p>
<p>DCAT is an RDF vocabulary well-suited to representing data catalogs such as <a href="https://www.data.gov/">data.gov</a> and <a href="http://data.gov.uk">data.gov.uk</a>. DCAT defines eight main classes:</p>
<ul>
<li> <code><a href="#Class:Catalog">dcat:Catalog</a></code> represents the catalog</li>
<li> <code><a href="#Class:Resource">dcat:Resource</a></code> represents an item in a catalog.</li>
<li> <code><a href="#Class:Dataset">dcat:Dataset</a></code> represents a dataset in a catalog.</li>
<li> <code><a href="#Class:Distribution">dcat:Distribution</a></code> represents an accessible form or representation of a dataset as for example a downloadable file.</li>
<li> <code><a href="#Class:Data_Service">dcat:DataService</a></code> represents a data service in a catalog.</li>
<li> <code><a href="#Class:Data_Distribution_Service">dcat:DataDistributionService</a></code> represents a service that provides access to distributions of datasets and extracts of datasets.</li>
<!-- <li> (<code><a href="#Class:DataTransformationService">dcat:DataTransformationService</a></code> represents a service that can transform a dataset, e.g. spatial coordinate transformation; interpolation or resampling of a dataset).</li> -->
<li> <code><a href="#Class:Discovery_Service">dcat:DiscoveryService</a></code> represents a service that supports discovery functions.</li>
<li> <code><a href="#Class:Catalog_Record">dcat:CatalogRecord</a></code> describes a dataset entry in the catalog, primarily concerning the registration information such as who added the item and when</li>
</ul>
<p>
A <b>dataset</b> in DCAT is defined as a "collection of data, published or curated by a single agent, and available for access or download in one or more formats".
A dataset is a conceptual entity, and can be represented by one or more <b>distributions</b> that serialize the dataset for transfer.
Distributions of a dataset can be provided via <b>data distribution services</b>.
Detailed properties for a data distribution service API are out of the scope of this version of DCAT. </p>
<p>Datasets and <b>data services</b>, and potentially other types of thing, <em title="MAY" class="rfc2119">MAY</em> be included in a <b>catalog</b>.
Types of data service that might be found in a catalog include data distribution services, <b>discovery services</b> such as portals and catalog services, <b>data transformation services</b> such as coordinate transformation services, re-sampling and interpolation services, and various <b>data processing services</b>.
</p>
<div class="note">
<p>
The scope of DCAT 2014 [[VOCAB-DCAT-20140116]] was limited to catalogs of datasets.
A number of use cases for the revision involve also having <b>data distribution services</b> as members of a catalog - see <a href="https://www.w3.org/TR/dcat-ucr/#ID6">DCAT Distribution to describe web services - ID6</a> and
<a href="https://www.w3.org/TR/dcat-ucr/#ID18">Modeling service-based data access - ID18</a>.
It has been decided to add an explicit class for Data Distribution Services in this revision of DCAT, and to enable these to be part of a Catalog.
Provision for other data services to also be part of a Catalog will also be made, as well as for Catalogs to be composed of other Catalogs.
See <a href="https://github.com/w3c/dxwg/issues/172">Issue #172</a>. </p>
<p>
The wiki page on <a href="https://github.com/w3c/dxwg/wiki/Cataloguing-data-services">Cataloguing data services</a> describes some proposals related to this requirement.
</p>
</div>
<p>A <b>CatalogRecord</b> describes an entry in the catalog. Notice that while <code>dcat:Resource</code> represents the dataset or service itself, <code>dcat:CatalogRecord</code> is the record that describes the registration of an item in the catalog. The use of <code>dcat:CatalogRecord</code> is considered optional. It is used to capture provenance information about entries in a catalog. If this distinction is not necessary then <code>dcat:CatalogRecord</code> can be safely ignored.</p>
<p class="note">
In DCAT 2014 [[VOCAB-DCAT-20140116]] <a href="#Class:Dataset">dcat:Dataset</a> was a sub-class of <a href="http://purl.org/dc/dcmitype/Dataset">dctype:Dataset</a>, which is a term of the <a href="http://dublincore.org/documents/dcmi-terms/#section-7">DCMI Types vocabulary</a> [[DCTERMS]].
This relationship has been removed in the revised DCAT vocabulary - see <a href="https://github.com/w3c/dxwg/issues/98">Issue #98</a>.
</p>
<figure id="fig1"><img alt="UML model of DCAT classes and properties" src="UML/DCAT-summary-all-attributes.png">
<figcaption>
Overview of DCAT model, showing the classes of resources that can be members of a Catalog and the relationships between them.
<br/>Along with the rest of the <a href="#vocabulary-overview">Vocabulary overview</a>, the diagram is <b>non-normative</b>.
Furthermore, while the diagram uses UML-style class notation, it should be interpreted following the usual RDF open-world assumptions around the presence/absence of properties, relationships, and their cardinality.
The properties shown in each class reflect those recommended in the descriptions of classes in the <a href="#vocabulary-specification">Vocabulary specification.
</a>Cardinalities are shown in a few places to reinforce expectations, but these are not axiomatized or enforced in any way by this recommendation.
</figcaption>
</figure>
<p id="blankNodes">RDF allows resources to have global identifiers (IRIs) or to be blank nodes. Blank nodes can be used to denote resources without explicitly naming them with an IRI. They can appear in the subject and object position of a triple [[rdf11-primer]].<br>
While blank nodes may offer flexibility for some use cases, in a Linked Data context, blank nodes limit our ability to collaboratively annotate data. A blank node resource cannot be the target of a link and it can't be annotated with new information from new sources. As one of the biggest benefits of the Linked Data approach is that "anyone can say anything anywhere", use of blank nodes undermines some of the advantages we can gain from wide adoption of the RDF model. Even within the closed world of a single application dataset, use of blank nodes can quickly become limiting when integrating new data [[LinkedDataPatterns]]. <br>
For these reasons, instances of the DCAT main classes <em title="SHOULD" class="rfc2119">SHOULD</em> have a global identifier, and use of blank nodes is generally discouraged when encoding DCAT in RDF.</p>
<p>All RDF examples in this document are written in Turtle syntax [[Turtle]].</p>
<section id="basic-example">
<h3>Basic Example</h3>
<p>This example provides a quick overview of how DCAT might be used to represent a government catalog and its datasets. </p>
<p>First, the catalog description:
</p>
<pre> :catalog
a dcat:Catalog ;
dct:title "Imaginary Catalog" ;
rdfs:label "Imaginary Catalog" ;
foaf:homepage <http://example.org/catalog> ;
dct:publisher :transparency-office ;
dct:language <http://id.loc.gov/vocabulary/iso639-1/en> ;
dcat:dataset :dataset-001 , :dataset-002 , :dataset-003 ;
.
</pre>
<p>The publisher of the catalog has the relative URI :transparency-office. Further description of the publisher can be provided as in the following example:
</p>
<pre> :transparency-office
a foaf:Organization ;
rdfs:label "Transparency Office" ;
.
</pre>
<p>The catalog lists each of its datasets via the dcat:dataset property. In the example above, an example dataset was mentioned with the relative URI :dataset-001. A possible description of it using DCAT is shown below:
</p>
<pre> :dataset-001
a dcat:Dataset ;
dct:title "Imaginary dataset" ;
dcat:keyword "accountability","transparency" ,"payments" ;
dct:creator :finance-employee-001 ;
dct:issued "2011-12-05"^^xsd:date ;
dct:modified "2011-12-05"^^xsd:date ;
dcat:contactPoint <http://example.org/transparency-office/contact> ;
dct:temporal <http://reference.data.gov.uk/id/quarter/2006-Q1> ;
dct:spatial <http://www.geonames.org/6695072> ;
dct:publisher :finance-ministry ;
dct:language <http://id.loc.gov/vocabulary/iso639-1/en> ;
dct:accrualPeriodicity <http://purl.org/linked-data/sdmx/2009/code#freq-W> ;
dcat:distribution :dataset-001-csv ;
.
</pre>
<p>In order to express the frequency of update in the example above, we chose to use an instance from the <a href="http://www.w3.org/TR/vocab-data-cube/#dsd-cog">Content-Oriented Guidelines</a> developed as part
of the <abbr title="World Wide Web Consortium">W3C</abbr> Data Cube Vocabulary [[VOCAB-DATA-CUBE]] efforts. Additionally, we chose to describe the spatial and temporal coverage of the example dataset using URIs from <a href="http://www.geonames.org/">Geonames</a> and the Interval dataset (originally available from http://reference.data.gov.uk/id/interval) from data.gov.uk, respectively. A contact point is also provided where comments and feedback about the dataset can be sent. Further details about the contact point, such as email address or telephone number, can be provided using vCard [[VCARD-RDF]].</p>
<p>The dataset distribution :dataset-001-csv can be downloaded as a 5Kb CSV file. This information is
represented via an RDF resource of type dcat:Distribution.
</p>
<pre> :dataset-001-csv
a dcat:Distribution ;
dcat:downloadURL <http://www.example.org/files/001.csv> ;
dct:title "CSV distribution of imaginary dataset 001" ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/csv> ;
dcat:byteSize "5120"^^xsd:decimal ;
.
</pre>
</section>
<section id="classifying-datasets">
<h3>Classifying datasets thematically</h3>
<p>The catalog classifies its datasets according to a set of domains represented by the relative URI :themes. SKOS can be used to describe the domains used:
</p>
<pre> :catalog dcat:themeTaxonomy :themes .
</pre>
<pre> :themes
a skos:ConceptScheme ;
skos:prefLabel "A set of domains to classify documents" ;
.
</pre>
<pre> :dataset-001 dcat:theme :accountability .
</pre>
<p>Notice that this dataset is classified under the domain represented by the relative URI :accountability.
It is recommended to define the concept as part of the concepts scheme identified by the URI :themes that was used to describe the catalog domains. An example SKOS description:
</p>
<pre> :accountability
a skos:Concept ;
skos:inScheme :themes ;
skos:prefLabel "Accountability" ;
.
</pre>
</section>
<section id="classifying-dataset-types">
<h3>Classifying dataset types</h3>
<p>
The type or genre of a dataset <em title="MAY" class="rfc2119">MAY</em> be indicated using the <a href="http://purl.org/dc/terms/type">dct:type</a> property.
The value of the property <em title="SHOULD" class="rfc2119">SHOULD</em> be taken from a well governed and broadly recognised set of resource types, such as the <a href="http://dublincore.org/documents/dcmi-terms/#section-7">DCMI Type Vocabulary</a>, the <a href="https://id.loc.gov/vocabulary/marcgt.html">MARC Genre/Terms Scheme</a>, the <a href="https://schema.datacite.org/meta/kernel-4.1/include/datacite-resourceType-v4.1.xsd">DataCite resource types</a> or the PARSE.Insight content-types from Re3data [[re3data-schema]].
</p>
<p>
In the following examples a (notional) dataset is classified separately using a values from different vocabularies.
</p>
<pre>
:dataset-001
rdf:type dcat:Dataset ;
dct:type <http://purl.org/dc/dcmitype/Text> ;
.
:dataset-001
rdf:type dcat:Dataset ;
dct:type <http://id.loc.gov/vocabulary/marcgt/man> ;
.
</pre>
<p>
It is also possible for multiple classifications to be present in a single description.
</p>
<pre>
:dataset-001
rdf:type dcat:Dataset ;
dct:type <http://purl.org/dc/dcmitype/Text> ;
dct:type <http://id.loc.gov/vocabulary/marcgt/man> ;
dct:type <http://registry.it.csiro.au/def/datacite/resourceType/Text> ;
dct:type <http://registry.it.csiro.au/def/re3data/contentType/doc> ;
.
<http://registry.it.csiro.au/def/datacite/resourceType/Text>
rdfs:label "Text" ;
dct:source "DataCite resource types" ;
.
<http://registry.it.csiro.au/def/re3data/contentType/doc>
rdfs:label "Standard office documents" ;
dct:source "Re3data content types" ;
.
</pre>
</section>
<section id="describing-catalog-records-metadata">
<h3>Describing catalog records metadata</h3>
<p>If the catalog publisher decides to keep metadata
describing its records (i.e. the records containing metadata
describing the datasets), dcat:CatalogRecord can be used. For example,
while :dataset-001 was issued on 2011-12-05, its description on Imaginary Catalog was added on 2011-12-11. This can be represented by DCAT as in the following:
</p>
<pre> :catalog dcat:record :record-001 .
</pre>
<pre> :record-001
a dcat:CatalogRecord ;
foaf:primaryTopic :dataset-001 ;
dct:issued "2011-12-11"^^xsd:date ;
.
</pre>
</section>
<section id="example-landing-page">
<h3>Dataset available only behind some Web page</h3>
<p>:dataset-002 is available as a CSV file. However :dataset-002 can only be obtained through some Web page
where the user needs to follow some links, provide some information and check some boxes
before accessing the data</p>
<pre> :dataset-002
a dcat:Dataset ;
dcat:landingPage <http://example.org/dataset-002.html> ;
dcat:distribution :dataset-002-csv ;
.
:dataset-002-csv
a dcat:Distribution ;
dcat:accessURL <http://example.org/dataset-002.html> ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/csv> ;
.
</pre>
Notice the use of a dcat:landingPage and the definition of the dcat:Distribution instance.
</section>
<section id="a-dataset-available-as-download-and-behind-some-web-page">
<h3>A dataset available as a download and behind some Web page</h3>
<p>On the other hand, :dataset-003 can be obtained through some landing page but also can be downloaded from a known URL.
</p>
<pre> :dataset-003
a dcat:Dataset ;
dcat:landingPage <http://example.org/dataset-003.html> ;
dcat:distribution :dataset-003-csv ;
.
:dataset-003-csv
a dcat:Distribution ;
dcat:downloadURL <http://example.org/dataset-003.csv> ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/csv> ;
.
</pre>
Notice that we used dcat:downloadURL with the downloadable distribution and that the other distribution accessible through the landing page
does not have to be defined as a separate dcat:Distribution instance.
</section>
<section id="bag-of-files">
<h3>Loosely structured catalog</h3>
<p>
In many legacy catalogues and repositories (e.g. CKAN), ‘datasets’ are ‘just a bag of files’. There is no distinction made between part/whole, distribution (representation), and other kinds of relationship (e.g. documentation, schema, supporting documents) from the dataset to each of the files.
</p>
<p>
If the nature of the relationships between a dataset and component resources in a catalogue, repository, or elsewhere are not known, <b>dct:relation</b> can be used:
</p>
<pre>
:d33937
dct:description "A set of RDF graphs representing the International [Chrono]stratigraphic Chart, ..." ;
dct:identifier "https://doi.org/10.25919/5b4d2b83cbf2d"^^xsd:anyURI ;
dct:creator <https://orcid.org/0000-0002-3884-3420>;
dct:relation <https://vocabs.ands.org.au/viewById/196> ;
dct:relation :ChronostratChart2017-02.pdf ;
dct:relation :ChronostratChart2017-02.jpg ;
dct:relation :timescale.zip ;
dct:relation :isc2017.jsonld ;
dct:relation :isc2017.nt ;
dct:relation :isc2017.rdf ;
dct:relation :isc2017.ttl ;
.
</pre>
<p>
If it is clear that any of these related resources is a proper <i>representation</i> of the dataset, dcat:distribution should be used.
</p>
<pre>
:d33937
rdf:type dcat:Dataset ;
dct:description "A set of RDF graphs representing the International [Chrono]stratigraphic Chart, ..." ;
dct:identifier "https://doi.org/10.25919/5b4d2b83cbf2d"^^xsd:anyURI ;
dct:relation <https://vocabs.ands.org.au/viewById/196> ;
dct:relation :ChronostratChart2017-02.pdf ;
dct:relation :ChronostratChart2017-02.jpg ;
dct:relation :timescale.zip ;
dcat:distribution :d33937-jsonld ;
dcat:distribution :d33937-nt ;
dcat:distribution :d33937-rdf ;
dcat:distribution :d33937-ttl ;
.
:d33937-jsonld rdf:type dcat:Distribution ;
dcat:downloadURL :isc2017.jsonld ;
dcat:byteSize "698039"^^xsd:decimal ;
dcat:mediaType <https://www.iana.org/assignments/media-types/application/ld+json> ;
.
:d33937-nt rdf:type dcat:Distribution ;
dcat:downloadURL :isc2017.nt ;
dcat:byteSize "2047874"^^xsd:decimal ;
dcat:mediaType <https://www.iana.org/assignments/media-types/application/n-triples> ;
.
:d33937-rdf rdf:type dcat:Distribution ;
dcat:downloadURL :isc2017.rdf ;
dcat:byteSize "1600569"^^xsd:decimal ;
dcat:mediaType <https://www.iana.org/assignments/media-types/application/rdf+xml> ;
.
:d33937-ttl rdf:type dcat:Distribution ;
dcat:downloadURL :isc2017.ttl ;
dcat:byteSize "531703"^^xsd:decimal ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/turtle> ;
.
</pre>
</section>
<section id="examples-dataset-provenance">
<h3>Dataset provenance</h3>
<p>
The provenance or business context of a dataset can be described using elements from the W3C Provenance Ontology [[!PROV-O]].
</p>
<p>
For example, a simple link from a dataset description to the project that generated the dataset can be formalized as follows (other details elided for clarity):
</p>
<pre>
dap:atnf-P366-2003SEPT
rdf:type dcat:Dataset ;
dct:bibliographicCitation "Burgay, M; McLaughlin, M; Kramer, M; Lyne, A; Joshi, B; Pearce, G; D'Amico, N; Possenti, A; Manchester, R; Camilo, F (2017): Parkes observations for project P366 semester 2003SEPT. v1. CSIRO. Data Collection. https://doi.org/10.4225/08/598dc08d07bb7" ;
dct:title "Parkes observations for project P366 semester 2003SEPT" ;
dcat:landingPage <https://data.csiro.au/dap/landingpage?pid=csiro:P366-2003SEPT> ;
prov:wasGeneratedBy dap:P366 ;
.
dap:P366
rdf:type prov:Activity ;
dct:type "Observation" ;
prov:startedAtTime "2000-11-01"^^xsd:date ;
prov:used dap:Parkes-radio-telescope ;
prov:wasInformedBy dap:ATNF ;
rdfs:label "P366 - Parkes multibeam high-latitude pulsar survey" ;
rdfs:seeAlso <https://doi.org/10.1111/j.1365-2966.2006.10100.x> ;
.
</pre>
<p>
Several properties capture provenance information, including within the citation and title, but the primary link to a formal description of the project is through <a href="#Property:dataset_wasgeneratedby">prov:wasGeneratedBy</a>.
A terse description of the project is shown as a <a href="http://www.w3.org/ns/prov#Activity">prov:Activity</a>, though this would not necessarily be part of the same catalog.
Note that as the project is ongoing, the activity has no end date.
</p>
<p>
Further provenance information might be provided using the other <i>starting point properties</i> from PROV, in particular <a href="http://www.w3.org/TR/prov-o/#wasAttributedTo">prov:wasAttributedTo</a> (to link to an agent associated with the dataset production) and <a href="http://www.w3.org/TR/prov-o/#Property:wasDerivedFrom">prov:wasDerivedFrom</a> (to link to a predecessor dataset). Both of these complement Dublin Core properties already used in DCAT, as follows:
</p>
<ul>
<li>
<b>prov:wasAttributedTo</b> provides a general link to all kinds of associated agents, such as project sponsors, managers, dataset owners, etc which are not correctly characterized using <b>dct:creator</b>, <b>dct:contributor</b> or <b>dct:publisher</b>.
</li>
<li>
<b>prov:wasDerivedFrom</b> supports a more specific relationship to an input or predecessor dataset compared with <b>dct:source</b>, which is not necessarily a previous dataset.
</li>
</ul>
<p>
For a more detailed discussion of the use of PROV for dataset provenance, including recommendations on the use of <i>qualified properties</i>, see the chapter on <a href="#prov-patterns">Provenance Patterns</a> below.
</p>
</section>
<section id="more-examples-needed">
<h3>More examples needed</h3>
<p class="note">
Need to add examples showing data distribution services and their relationship to datasets and distributions.
</p>
<p class="note">
Need to add examples showing other data services.
</p>
</section>
</section>
<section id="vocabulary-specification">
<h2>Vocabulary specification</h2>
<section id="RDF-representation">
<h3>RDF representation</h3>
<p class="note">
The DCAT RDF representation is modularized into several files or graphs to help users access a version of DCAT with just the alignments that they need. This mechanism can also be used to capture different levels of axiomatization, though the status of such proposals has not been finalized. See <a href="https://github.com/w3c/dxwg/issues/134">Issue #134</a> and the issues enumerated below.
</p>
<div class="issue" data-number="65">
<p>
Guidance on the use DCAT in a weakly-axiomatized environment, such as schema.org, has been identified as a requirement to be satisfied in this revision of DCAT.
</p>
<p>
An <a href="https://github.com/w3c/dxwg/blob/gh-pages/dcat/rdf/schema.ttl">RDF graph containing a proposed alignment of DCAT with schema.org</a> is available. Comments on this alignment are invited.
</p>
</div>
<p class="issue" data-number="105">
The use of guarded constraints (existence, cardinality, range-type) to control the use of the recommended properties in the context of a class is being considered as part of the revision of DCAT.
</p>
<p class="issue" data-number="110">
The axiomatization of DCAT 2014 used global domain and range constraints for many of the properties defined in the DCAT namespace [[VOCAB-DCAT-20140116]]. This makes quite strong ontological commitments, some of which are now being reconsidered - see individual issues noted inline below.
</p>
<p>The (revised) DCAT vocabulary is <a href="https://raw.githubusercontent.com/w3c/dxwg/gh-pages/dcat/rdf/">available in RDF</a>.
The primary artefact <a href="https://raw.githubusercontent.com/w3c/dxwg/gh-pages/dcat/rdf/dcat.ttl">dcat.ttl</a> is a serialization of the core DCAT vocabulary.
Alongside it are a set of other RDF files that provide additional information, including:</p>
<ol>
<li>
alignments to other vocabularies
</li>
<li>
additional axioms, which can be useful in some contexts
</li>
<li>
some profiles of DCAT, including a profile that corresponds to the 2014 version of DCAT [[VOCAB-DCAT-20140116]]
</li>
</ol>
<p class="issue" data-number="144">
The implementation of a DCAT 2014 profile of the revised DCAT is being considered.
</p>
</section>
<section id="dependencies">
<h3>Dependencies</h3>
<p>
The definitions (including domain and range) of terms outside the DCAT namespace are provided here only for convenience and <em title="MUST NOT" class="rfc2119">MUST NOT</em> be considered normative. The authoritative definitions of these terms are in the corresponding specifications: [[!DC11]], [[!DCTERMS]], [[!FOAF]], [[!RDF-SCHEMA]], [[!SKOS-REFERENCE]], [[!XMLSCHEMA11-2]] and [[!VCARD-RDF]].
</p>
<p class="note">Description of DCAT vocabulary elements from DCAT 2014 [[VOCAB-DCAT-20140116]] except where indicated.</p>
</section>
<section id="Class:Catalog">
<h3>Class: Catalog</h3>
<p>The following properties are recommended for use on this class:
<a href="#Property:catalog_catalog_record">catalog record</a>,
<a href="#Property:catalog_hasPart">hasPart</a>,
<a href="#Property:catalog_dataset">dataset</a>,
<a href="#Property:catalog_service">service</a>,
<a href="#Property:catalog_catalog">catalog</a>,
<a href="#Property:catalog_description">description</a>,
<a href="#Property:catalog_homepage">homepage</a>,
<a href="#Property:catalog_language">language</a>,
<a href="#Property:catalog_license">license</a>,
<a href="#Property:catalog_publisher">publisher</a>,
<a href="#Property:catalog_release_date">release date</a>,
<a href="#Property:catalog_rights">rights</a>,
<a href="#Property:catalog_spatial">spatial/geographical</a>,
<a href="#Property:catalog_themes">themes</a>,
<a href="#Property:catalog_title">title</a>,
<a href="#Property:catalog_update_date">update/modification date</a>
</p>
<div class="note">
<p>
The scope of DCAT 2014 was limited to catalogs of datasets [[VOCAB-DCAT-20140116]].
A number of use cases for the revision involve also having <b>data distribution services</b> as members of a catalog - see <a href="https://www.w3.org/TR/dcat-ucr/#ID6">DCAT Distribution to describe web services - ID6</a> and
<a href="https://www.w3.org/TR/dcat-ucr/#ID18">Modeling service-based data access - ID18</a>.
It has been decided to add an explicit class for Data Distribution Services in this revision of DCAT, and to enable these to be part of a Catalog.
Provision for other services to also be part of a Catalog will also be made, as well as for Catalogs to be composed of other Catalogs.
See <a href="https://github.com/w3c/dxwg/issues/172">Issue #172</a> and <a href="https://github.com/w3c/dxwg/issues/116">Issue #116</a>. </p>
</div>
<table class="definition">
<thead><tr><th>RDF Class:</th><th><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></th></tr></thead>
<tbody>
<tr><td class="prop">Sub-class of:</td><td><a href="#Class:Dataset">Dataset</a></td></tr>
<tr><td class="prop">Definition:</td><td>A curated collection of metadata about datasets and data services</td></tr>
<tr><td class="prop">Usage note:</td><td>A web-based data catalog is typically represented as a single instance of this class.</td></tr>
<tr><td class="prop">See also:</td><td> <a href="#Class:Catalog_Record">Catalog record</a>, <a href="#Class:Dataset">Dataset</a></td></tr>
</tbody>
</table>
<section id="Property:catalog_title">
<h4>Property: title</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/title">dct:title</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A name given to the catalog.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_description">
<h4>Property: description</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/description">dct:description</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A free-text account of the catalog.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_release_date">
<h4>Property: release date</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/issued">dct:issued</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Date of formal issuance (e.g., publication) of the catalog.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a>
encoded using the relevant ISO 8601 Date and Time compliant string [[!DATETIME]] and typed using the appropriate XML Schema datatype [[XMLSCHEMA11-2]]
</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Property:resource_release_date" title=""> resource release date</a>, <a href="#Property:record_listing_date" title=""> catalog record listing date</a> and <a href="#Property:distribution_release_date" title=""> distribution release date</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_update_date">
<h4>Property: update/modification date</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/modified">dct:modified</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Most recent date on which the catalog was changed, updated or modified.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a>
encoded using the relevant ISO 8601 Date and Time compliant string [[!DATETIME]] and typed using the appropriate XML Schema datatype [[XMLSCHEMA11-2]]
</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Property:resource_update_date" title=""> resource modification date</a>, <a href="#Property:record_update_date" title=""> catalog record modification date</a> and <a href="#Property:distribution_update_date" title=""> distribution modification date</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_language">
<h4>Property: language</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/language">dct:language</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A language of the catalog. This refers to the language used in the textual metadata describing titles, descriptions, etc. of the resources (i.e. datasets and services) in the catalog.</td></tr>
<tr><td class="prop">Range:</td><td>
<a href="http://purl.org/dc/terms/LinguisticSystem">dct:LinguisticSystem</a>
<br>
Resources defined by the Library of Congress (<a href="http://id.loc.gov/vocabulary/iso639-1.html">1</a>,
<a href="http://id.loc.gov/vocabulary/iso639-2.html">2</a>) <em title="SHOULD" class="rfc2119">SHOULD</em> be used.
<br>
If a ISO 639-1 (two-letter) code is defined for language, then its corresponding IRI <em title="SHOULD" class="rfc2119">SHOULD</em> be used; if no ISO 639-1 code is defined, then IRI corresponding to the ISO 639-2 (three-letter) code <em title="SHOULD" class="rfc2119">SHOULD</em> be used.</td></tr>
<tr><td class="prop">Usage note:</td><td>Multiple values can be used. The publisher might also choose to describe the language on the resource (e.g. dataset, or service) level (see <a href="#Property:resource_language">dataset language</a>).</td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_homepage">
<h4>Property: homepage</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://xmlns.com/foaf/0.1/homepage">foaf:homepage</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A homepage of the catalog (a public web document usually available in HTML).</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://xmlns.com/foaf/0.1/Document">foaf:Document</a></td></tr>
<tr><td class="prop">Usage note:</td><td><a href="http://xmlns.com/foaf/0.1/homepage">foaf:homepage</a> is an inverse functional property (IFP) which means that it <em title="SHOULD" class="rfc2119">SHOULD</em> be unique and precisely identify the catalog. This allows smushing various descriptions of the catalog when different URIs are used.</td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_publisher">
<h4>Property: publisher</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/publisher">dct:publisher</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>The entity responsible for making the catalog available.</td></tr>
<tr><td class="prop">Usage note:</td><td>Resources of type <a href="http://xmlns.com/foaf/0.1/Agent">foaf:Agent</a>
are recommended as values for this property.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Class:Organization_Person">Class: Organization/Person</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_spatial">
<h4>Property: spatial/geographic </h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/spatial">dct:spatial</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>The geographical area covered by the catalog.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://purl.org/dc/terms/Location">dct:Location</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_themes">
<h4>Property: themes</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#themeTaxonomy">dcat:themeTaxonomy</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A knowledge organization system (KOS) used to classify catalog's datasets and services.</td></tr>
<tr><td class="prop">Domain:</td><td><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2004/02/skos/core#ConceptScheme">skos:ConceptScheme</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_license">
<h4>Property: license</h4>
<p class="issue" data-number="114">
Models for the kind of license or rights representation indicated by the dct:license property are being considered as part of the revision of DCAT.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/license">dct:license</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A legal document under which the <strong>catalog</strong>
is made available and <strong>not the datasets or services</strong></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://purl.org/dc/terms/LicenseDocument">dct:LicenseDocument</a></td></tr>
<tr><td class="prop">Usage note:</td><td>If the license of the catalog applies to all of its
datasets and distributions, it <em title="SHOULD" class="rfc2119">SHOULD</em> also be replicated on each distribution.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Property:catalog_rights">catalog rights</a>,
<a href="#Property:distribution_license">distribution license</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_rights">
<h4>Property: rights</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/rights">dct:rights</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Information about the rights under which the <strong>catalog</strong>
can be used/reused, but <strong>not the datasets or services</strong> listed.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://purl.org/dc/terms/RightsStatement">dct:RightsStatement</a></td></tr>
<tr><td class="prop">Usage note:</td><td>If the rights associated with the catalog applies to all of its
datasets and distributions, it <em title="SHOULD" class="rfc2119">SHOULD</em> also be replicated on each distribution.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Property:catalog_license">catalog license</a>,
<a href="#Property:distribution_rights">distribution rights</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_hasPart">
<h4>Property: hasPart</h4>
<p class="note">
Explicit use of this property added in this revision of DCAT.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/hasPart">dct:hasPart</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>An item that is listed in the catalog.</td></tr>
<tr><td class="prop">Domain:</td><td><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/ns/dcat#Resource">dcat:Resource</a></td></tr>
<tr><td class="prop">Usage note:</td><td>This is the most general predicate for membership of a catalog. Use of a more specific sub-property is recommended when available. </td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_dataset">
<h4>Property: dataset</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#dataset">dcat:dataset</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A collection of data that is listed in the catalog.</td></tr>
<tr><td class="prop">Sub property of:</td><td><a href="http://purl.org/dc/terms/hasPart">dct:hasPart</a></td></tr>
<tr><td class="prop">Domain:</td><td><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/ns/dcat#Dataset">dcat:Dataset</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_service">
<h4>Property: service</h4>
<p class="note">
Property added in this revision of DCAT.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#service">dcat:service</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A site or end-point that is listed in the catalog.</td></tr>
<tr><td class="prop">Sub property of:</td><td><a href="http://purl.org/dc/terms/hasPart">dct:hasPart</a></td></tr>
<tr><td class="prop">Domain:</td><td><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/ns/dcat#Dataset">dcat:DataService</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_catalog">
<h4>Property: catalog</h4>
<p class="note">
Property added in this revision of DCAT.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#catalog">dcat:catalog</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A catalog whose contents are of interest in the context of this catalog</td></tr>
<tr><td class="prop">Sub property of:</td><td><a href="http://purl.org/dc/terms/hasPart">dct:dataset</a></td></tr>
<tr><td class="prop">Domain:</td><td><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/ns/dcat#Dataset">dcat:Catalog</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_catalog_record">
<h4>Property: catalog record</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#record">dcat:record</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A record describing the registration of a single dataset or dataservice that is part of the catalog.</td></tr>
<tr><td class="prop">Domain:</td><td><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/ns/dcat#CatalogRecord">dcat:CatalogRecord</a></td></tr>
</tbody>
</table>
</section>
</section> <!-- end Class:Catalog -->
<section id="Class:Resource">
<h3>Class: Catalogued Resource</h3>
<p>The following properties are recommended for use on this class:
<a href="#Property:resource_conformsto">conformsTo</a>,
<a href="#Property:resource_contact_point">contact point</a>,
<a href="#Property:resource_description">description</a>,
<a href="#Property:resource_identifier">identifier</a>,
<a href="#Property:resource_keyword">keyword/tag</a>,
<a href="#Property:resource_landing_page">landing page</a>,
<a href="#Property:resource_language">resource language</a>,
<a href="#Property:resource_relation">relation</a>,
<a href="#Property:resource_publisher">publisher</a>,
<a href="#Property:resource_release_date">release date</a>,
<a href="#Property:resource_theme">theme/category</a>,
<a href="#Property:resource_title">title</a>,
<a href="#Property:resource_type">type/genre</a>,
<a href="#Property:resource_update_date">update/modification date</a>,
</p>
<p class="issue" data-number="62">
The possible association of items with zero or multiple catalogs has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
<p class="issue" data-number="66">
The need to be able to link a catalogued resource with the source of funding that supported its production has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
<p class="issue" data-number="71">
The need to be able to describe the business or project context related to production of a catalogued resource has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
<!--
-- this issue already closed - prov:wasGeneratedBy added to dcat:Dataset (but not to dcat:Resource) --
<p class="issue" data-number="77">
The need to be able to link a catalogued resource with the business or project context of its production has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
-->
<table class="definition">
<thead><tr><th>RDF Class:</th><th><a href="http://www.w3.org/ns/dcat#Resource">dcat:Resource</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Resource published or curated by a single agent.</td></tr>
<tr><td class="prop">Usage note:</td><td>The class of all catalogued resources, the superclass of
<a href="#Class:Dataset">dcat:Dataset</a>, <a href="#Class:Data_Service">dcat:DataService</a>, <a href="#Class:Catalog">dcat:Catalog</a> and any other member of a <a href="#Class:Catalog">dcat:Catalog</a>.
This class carries properties common to all catalogued resources, including datasets and data services.
It is strongly recommended to use a more specific sub-class when available.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Class:Catalog_Record" title="">Catalog record</a></td></tr>
</tbody>
</table>
<p class="note">
The class <a href="#Class:Resource">dcat:Resource</a> has been added to the DCAT vocabulary in this revision.
</p>
<section id="Property:resource_title">
<h4>Property: title</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/title">dct:title</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A name given to the item.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_description">
<h4>Property: description</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/description">dct:description</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>free-text account of the item.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_release_date">
<h4>Property: release date</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/issued">dct:issued</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Date of formal issuance (e.g., publication) of the item.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a>
encoded using the relevant ISO 8601 Date and Time compliant string [[!DATETIME]] and typed using the appropriate XML Schema datatype [[XMLSCHEMA11-2]]
</td></tr>
<tr><td class="prop">Usage note:</td><td>This property <em title="SHOULD" class="rfc2119">SHOULD</em> be set using the first known date of issuance.</td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_update_date">
<h4>Property: update/modification date</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/modified">dct:modified</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Most recent date on which the item was changed, updated or modified.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal">rdfs:Literal</a>
encoded using the relevant ISO 8601 Date and Time compliant string [[!DATETIME]] and typed using the appropriate XML Schema datatype [[XMLSCHEMA11-2]]
</td></tr>
<tr><td class="prop">Usage note:</td><td>The value of this property indicates a change to the actual item, not a change to the catalog record. An absent value <em title="MAY" class="rfc2119">MAY</em> indicate that the item has never changed after its initial publication, or that the date of last modification is not known, or that the item is continuously updated.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Property:dataset_frequency">dataset frequency</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_language">
<h4>Property: language</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/language">dct:language</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>The language of the item.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://purl.org/dc/terms/LinguisticSystem">dct:LinguisticSystem</a>
<br>
Resources defined by the Library of Congress (<a href="http://id.loc.gov/vocabulary/iso639-1.html">1</a>,
<a href="http://id.loc.gov/vocabulary/iso639-2.html">2</a>) <em title="SHOULD" class="rfc2119">SHOULD</em> be used.
<br>
If a ISO 639-1 (two-letter) code is defined for language, then its corresponding IRI <em title="SHOULD" class="rfc2119">SHOULD</em> be used; if no ISO 639-1 code is defined, then IRI corresponding to the ISO 639-2 (three-letter) code <em title="SHOULD" class="rfc2119">SHOULD</em> be used.</td></tr>
<tr><td class="prop">Usage note:</td><td>This overrides the value of the <a href="#Property:catalog_language">catalog language</a> in case of conflict.
If the item is available in multiple languages, use multiple values for this property. If each language is available separately for a dataset, define an instance of dcat:Distribution for each language and describe the specific language of each distribution using dct:language (i.e. the dataset will have multiple dct:language values and each distribution will have one of these languages as value of its dct:language property).</td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_publisher">
<h4>Property: publisher</h4>
<p class="issue" data-number="80">
The desire to have qualified forms of properties (as done in [[PROV-O]]) has been raised. If dcat:Dataset is a prov:Entity (not decided yet) then `publisher` could be a qualified prov:Entity -> prov:Agent relationship.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/publisher">dct:publisher</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>The entity responsible for making the item available.</td></tr>
<tr><td class="prop">Usage note:</td><td>Resources of type <a href="http://xmlns.com/foaf/0.1/Agent">foaf:Agent</a>
are recommended as values for this property.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Class:Organization_Person">Class: Organization/Person</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_identifier">
<h4>Property: identifier</h4>
<p class="issue" data-number="53">
The desirability of dereferenceable identifiers has been raised as an item for consideration in the revision of DCAT. dct:identifier has limited expressivity for this. It has been suggested that ADMS identifier, or a property from another ontology might be recruited to help DCAT in this area.
</p>
<p class="issue" data-number="67">
The need to clearly distinguish between primary and legacy identifiers for a dataset has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
<p class="issue" data-number="68">