Changes between Version 54 and Version 55 of rdfstore


Ignore:
Timestamp:
10/29/12 22:08:29 (12 years ago)
Author:
simonp
Comment:

--

Legend:

Unmodified
Added
Removed
Modified

  • rdfstore

    v54 v55  
    3434 * '''RDF at Wikipedia''': http://en.wikipedia.org/wiki/Resource_Description_Framework
    3535 * '''RDF/XML W3C Document''': http://www.w3.org/TR/rdf-syntax-grammar/
     36 * '''RDF at W3C Schools''': http://www.w3schools.com/rdf
    3637 * '''Mappings from ISO metadata standards to RDF''':  http://def.seegrid.csiro.au/isotc211/iso19115/2003/ (mapping from ISO19115 to RDF), http://def.seegrid.csiro.au/isotc211/iso19119/2005/ (mapping from ISO19119 to RDF)
    3738 * '''GIT Repository of GeoNetwork Branch developed by UWA Developers''': https://github.com/cipherj/core-geonetwork.git (rdf-store branch)
    … …  
    5051=== RDF, RDFS and OWL ===
    5152
    52 RDF (Resource Description Framework) is a general method to decompose knowledge into simple facts consisting of entity-attribute-value (a triple known as subject-predicate-object in RDF terms). As an example in the metadata context, an RDF triple representing a fact from a metadata record could be:
     53RDF (Resource Description Framework) is a general method to decompose knowledge into simple facts consisting of entity-attribute-value (a triple confusingly rebadged as subject-predicate-object in RDF!). As an example in the metadata context, an RDF triple representing a fact from a metadata record could be:
    5354
    5455{{{
    55  dataset:2d41a526-a595-4c57-a144-23ce4a922437-title-'A Vegetation Map Of Tasmania'
     56 urn:metadata:2d41a526-a595-4c57-a144-23ce4a922437-title-'A Vegetation Map Of Tasmania'
    5657}}}
    5758
    58 where the entity/subject is dataset:2d41a526-a595-4c57-a144-23ce4a922437, the attribute/predicate is title and the value/object is the literal: 'A Vegetation Map Of Tasmania'. Basically, the subject/entity and the value/object are 'things' and the attribute is the relationship between them.
     59where the entity/subject is urn:metadata:2d41a526-a595-4c57-a144-23ce4a922437, the attribute/predicate is title and the value/object is: 'A Vegetation Map Of Tasmania'. Basically, the subject/entity and the value/object are 'things' and the attribute is the relationship between them or in english: "The title of urn:metadata:2d41a526-a595-4c57-a144-23ce4a922437 is 'A Vegetation Map of Tasmania'"
    5960
    6061RDF has an XML implementation (see http://www.w3.org/TR/rdf-syntax-grammar). This triple encoded in RDF/XML might look like:
    … …  
    6263{{{
    6364<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    64          xmlns:dc="http://purl.org/dc/">
    65         <rdf:Description rdf:about="urn:dataset:2d41a526-a595-4c57-a144-23ce4a922437">
    66              <dc:title>A Vegetation Map Of Tasmania</dc:title>
     65         xmlns:my="http://mynamespace.org.au">
     66        <rdf:Description rdf:about="urn:metadata:2d41a526-a595-4c57-a144-23ce4a922437">
     67             <my:title>A Vegetation Map Of Tasmania</my:title>
    6768        </rdf:Description>
    6869</rdf:RDF>
    6970}}}
    7071
    71 RDFS (or RDF Schema) adds the concept that each triplet may be a class and defines the rules governing classes (eg. specialization) - so we can now represent classes of 'things' and the different types of relationships between these 'things' as an RDF triple. So for example, we might define the following triple:
     72We have introduced a namespace (prefix my) to distinguish our title element from those elements provided by the RDF framework (they have namespace prefix rdf). To avoid reinventing new elements, the RDF/XML standard has introduced the dublin
     73
     74RDFS (or RDF Schema) adds the concept that each triplet may be a class and defines the rules governing classes (eg. specialization) - so we can now represent classes of 'things' and the different types of relationships between these 'things' as an RDF triple. So for example, we might define the following triples:
    7275
    7376{{{
     77 dataset:2d41a526-a595-4c57-a144-23ce4a922437-my:citation-citation1
     78 dataset:2d41a526-a595-4c57-a144-23ce4a922437-dc:title-'A Vegetation Map Of Tasmania'
     79 
     80}}} 
    7481
    75 }}} 
     82where the entity/subject is dataset:2d41a526-a595-4c57-a144-23ce4a922437
    7683
    7784OWL (Web Ontology Language) adds inference rules to RDF/RDFS.