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How to use RDF-STaX?

RDF stream type usage is often a subjective matter, so RDF-STaX provides facilities for making subjective assertions about RDF stream types. For example: I see this resource as an RDF graph stream, because (...), as opposed to strict, universal classification.

The assertions can be made by anyone, anywhere. You can use RDF-STaX to annotate published streams, datasets, research papers, software, and more.

Annotating RDF stream types

Making a statement about something's RDF stream type is very straightforward. For example, to say that <https://example.org/some-resource> is an RDF graph stream, you would use the stax:RdfStreamTypeUsage class:

@prefix stax: <https://w3id.org/stax/ontology#> .

_:usage a stax:RdfStreamTypeUsage ;
    stax:hasStreamType stax:graphStream ;
    stax:isUsageOf <https://example.org/some-resource> .

It is recommended (but not required) to have one stax:RdfStreamTypeUsage instance per annotated resource and per RDF stream type. This makes it easier to find all the annotations for a given resource or stream type.

You can also make the statement in reverse, by annotating the resource itself. This can be especially useful when annotating RDF streams on the Web or in a dataset. The following three examples illustrate combining RDF-STaX with other vocabularies for describing datasets and streams (VoCaLS, VoID, DCAT).

Example: VoCaLS RDFStream (click to expand)

To annotate a vocals:RDFStream from the VoCaLS Vocabulary:

@prefix stax: <https://w3id.org/stax/ontology#> .
@prefix vocals: <http://w3id.org/rsp/vocals#> .

_:stream a vocals:RDFStream ;
    # ... other properties of the stream ...
    stax:hasStreamTypeUsage [
        a stax:RdfStreamTypeUsage ;
        stax:hasStreamType stax:graphStream
    ] .
Example: VoID Dataset (click to expand)

To annotate a void:Dataset from the VoID Vocabulary:

@prefix stax: <https://w3id.org/stax/ontology#> .
@prefix void: <http://rdfs.org/ns/void#> .

_:dataset a void:Dataset ;
    # ... other properties of the dataset ...
    stax:hasStreamTypeUsage [
        a stax:RdfStreamTypeUsage ;
        stax:hasStreamType stax:flatTripleStream
    ] .

In VoID, void:Dataset refers to a set of triples, which can be viewed as a flat RDF triple stream.

Example: DCAT Distribution (click to expand)

In DCAT, a dataset may have multiple representations (dcat:Distribution). Thus, tou may want to annotate the distribution, not the dataset itself:

@prefix dcat: <http://www.w3.org/ns/dcat#> .
@prefix stax: <https://w3id.org/stax/ontology#> .

_:dataset a dcat:Dataset ;
    # ... other properties of the dataset ...
    dcat:distribution [
        a dcat:Distribution ;
        # ... other properties of the distribution ...
        stax:hasStreamTypeUsage [
            a stax:RdfStreamTypeUsage ;
            stax:hasStreamType stax:datasetStream
        ]
    ] .

Of course, annotating the dataset itself also makes sense, if you want to make a statement about the dataset as a whole.

Adding more information

The stax:RdfStreamTypeUsage instance is a good place to put additional information about the usage, such as a textual explanation, the source of the information, or the author of the statement. For example:

@prefix cito: <http://purl.org/spar/cito/> .
@prefix dcterms: <http://purl.org/dc/terms/> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix stax: <https://w3id.org/stax/ontology#> .

_:usage a stax:RdfStreamTypeUsage ;
    rdfs:comment "The authors state that for their proposed system, 'the streaming element (i.e. a single message) (...) is a set of triples'. Therefore, it uses an RDF graph stream."@en ;
    stax:hasStreamType stax:graphStream ;
    stax:isUsageOf <https://doi.org/10.1109/ICSTCC.2017.8107003> ;
    cito:citesAsEvidence <https://doi.org/10.1109/ICSTCC.2017.8107003> ;
    dcterms:creator <https://orcid.org/0000-0002-2543-9461> .

You can use whatever properties you like, however, the following are recommended:

  • CiTO ontology for typing the citations.
  • DCMI Metadata Terms for the statement author information.
  • rdfs:comment for the textual explanation.
  • For statement creators, we recommend using ORCID.
  • For research works, we recommend using DOI.

Making RDF stream type usage nanopublications

This subjective style of RDF-STaX meshes very well with the idea of nanopublications, small snippets of scientific knowledge. See the documentation page on nanopublications for more information on how to find, use, and create them.

See also