--- a/microdata-rdf/index.html Sat Sep 08 18:26:23 2012 -0700
+++ b/microdata-rdf/index.html Tue Sep 11 11:45:35 2012 -0700
@@ -84,7 +84,7 @@
wgURI: "http://www.w3.org/2001/sw/interest/",
// name (with the @w3c.org) of the public mailing to which comments are due
- wgPublicList: "public-html-data-tf",
+ wgPublicList: "semantic-web",
// URI of the patent status for this WG, for Rec-track documents
// !!!! IMPORTANT !!!!
@@ -366,9 +366,15 @@
</tr>
<tr>
- <td>rdfs:</td>
+ <td>rdf:</td>
<td>
- http://www.w3.org/2000/01/rdf-schema#</td>
+ http://www.w3.org/1999/02/22-rdf-syntax-ns#</td>
+ </tr>
+
+ <tr>
+ <td>rdfa:</td>
+ <td>
+ http://www.w3.org/ns/rdfa#</td>
</tr>
<tr>
@@ -617,20 +623,20 @@
to choose the most useful representation. For example, consider the following:</p>
<pre class="example" data-transform="updateExample">
<!--
-<div itemscope="" itemtype="http://schema.org/MusicPlaylist">
+<div itemscope itemtype="http://schema.org/MusicPlaylist">
<span itemprop="name">Classic Rock Playlist</span>
<meta itemprop="numTracks" content="2"/>
<p>Including works by
<span itemprop="byArtist">Lynard Skynard</span> and
<span itemprop="byArtist">AC/DC</span></p>.
- <div itemprop="tracks" itemscope="" itemtype="http://schema.org/MusicRecording">
+ <div itemprop="tracks" itemscope itemtype="http://schema.org/MusicRecording">
1.<span itemprop="name">Sweet Home Alabama</span> -
<span itemprop="byArtist">Lynard Skynard</span>
<link href="sweet-home-alabama" itemprop="url" />
</div>
- <div itemprop="tracks" itemscope="" itemtype="http://schema.org/MusicRecording">
+ <div itemprop="tracks" itemscope itemtype="http://schema.org/MusicRecording">
2.<span itemprop="name">Shook you all Night Long</span> -
<span itemprop="byArtist">AC/DC</span>
<link href="shook-you-all-night-long" itemprop="url" />
@@ -643,14 +649,18 @@
<!--
@prefix md: <http://www.w3.org/ns/md#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfa: <http://www.w3.org/ns/rdfa#> .
@prefix schema: <http://schema.org/> .
-<> md:item [ a schema:MusicPlaylist;
- schema:name "Classic Rock Playlist";
- schema:byArtist ("Lynard Skynard" "AC/DC");
- schema:numTracks "2";
- schema:tracks _:track1, _:track2, (_:track1 _:track2)
-] .
+<> md:item [
+ a schema:MusicPlaylist;
+ schema:name "Classic Rock Playlist";
+ schema:byArtist ("Lynard Skynard" "AC/DC");
+ schema:numTracks "2";
+ schema:tracks _:track1, _:track2, (_:track1 _:track2)
+ ];
+ rdfa:usesVocabulary schema:
+ .
_:track1 a schema:MusicRecording;
schema:byArtist ("Lynard Skynard");
schema:name "Sweet Home Alabama";
@@ -722,10 +732,8 @@
<p>Microdata requires that all values of <a class="aref">itemtype</a> come from the same vocabulary. This
is required as <a class="aref">itemprop</a> values are resolved relative to that vocabulary. However,
it is often useful to define an <a>item</a> to have types from multiple different vocabularies.</p>
- <p>Vocabulary expansion relies on a very small
- sub-set of OWL entailment [[!OWL2-OVERVIEW]] to generate triples based on
- rules and property/class relationships described in the <a>registry</a> and
- in referenced vocabularies.
+ <p>Vocabulary expansion uses simple rules to generate additional triples based on
+ rules and property relationships described in the <a>registry</a>.
Within the <a>registry</a>, a property definition may have either <code>equivalentProperty</code>
or <code>subPropertyOf</code> keys having a IRI value (or array of IRI values)
of the associated property. Such an
@@ -733,8 +741,13 @@
property IRI with the target property IRI using either
<code>http://www.w3.org/2000/01/rdf-schema#subPropertyOf</code> or
<code>http://www.w3.org/2002/07/owl#equivalentProperty</code> predicates.</p>
+ <p>To allow [[RDFA-CORE]] processors to be used for microdata vocabulary expansion, microdata acts as if
+ there is an implicit <code>@vocab</code> attribute set to a detected vocabulary by emitting
+ a triple using the <code>rdfa:usesVocabulary</code> predicate.</p>
<p>Vocabulary expansion MAY be performed as
- part of a larger RDF toolset including, for example, an OWL 2 RL reasoner.
+ part of a larger RDF toolset including, for example,
+ an <cite><a href="http://www.w3.org/TR/2009/REC-owl2-profiles-20091027/#OWL_2_RL">OWL 2 RL</a></cite> reasoner
+ (see [[OWL2-PROFILES]]).
Alternatively, expansion MAY
also be done using a separate and dedicated (e.g., rule based) reasoner
after the triples have been generated, or as the last
@@ -765,6 +778,7 @@
<pre class="example" data-transform="updateExample">
<!--
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfa: <http://www.w3.org/ns/rdfa#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix schema: <http://schema.org/> .
@@ -772,25 +786,27 @@
[ a schema:Product;
schema:additionalType <http://www.productontology.org/id/Laser_printer> .
schema:name "Laser Printer"]
-) .
+ );
+ rdfa:usesVocabulary schema: .
schema:additionalProperty rdfs:subPropertyOf rdf:type .
-->
</pre>
- <p>After performing OWL2 entailment, an additional <code>rdf:type</code> triple is generated:</p>
+ <p>After performing vocabulary entailment, an additional <code>rdf:type</code> triple is generated:</p>
<pre class="example" data-transform="updateExample">
<!--
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix schema: <http://schema.org/> .
-\
+
<> md:item (
[ a schema:Product, <http://www.productontology.org/id/Laser_printer>;
schema:additionalType <http://www.productontology.org/id/Laser_printer> .
schema:name "Laser Printer"]
-) .
+ )
+ rdfa:usesVocabulary schema: .
schema:additionalProperty rdfs:subPropertyOf rdf:type .
-->
@@ -799,8 +815,8 @@
<section>
<h2>Vocabulary Entailment</h2>
<p> For the purpose of vocabulary processing, microdata uses a very
- restricted subset of the OWL vocabulary and is based on the RDF-Based
- Semantics of OWL [[!OWL2-RDF-BASED-SEMANTICS]].
+ restricted subset of the OWL2 vocabulary and is based on the RDF-Based
+ Semantics of OWL2 [[!OWL2-RDF-BASED-SEMANTICS]].
Vocabulary Entailment uses the following terms: </p>
<ul>
<li><code>rdfs:subPropertyOf</code></li>
@@ -826,9 +842,9 @@
<p>The entailment described in this section is the <em>minimum</em>
useful level for microdata. Processors may, of course, choose to follow
more powerful entailment regimes, e.g., include full RDFS [[!RDF-MT]]
- or OWL [[!OWL2-OVERVIEW]] entailments. Using those entailments
+ or OWL2 [[!OWL2-OVERVIEW]] entailments. Using those entailments
applications may perform datatype validation by checking <code>rdfs:range</code>
- of a property, or use the advanced facilities offered by, e.g., OWL’s
+ of a property, or use the advanced facilities offered by, e.g., OWL2’s
property chains to interlink vocabularies further.</p>
<p class="note">[[RDFA-CORE]] implements a more complete form of vocabulary entailement,
including retrieving the vocabulary URI to find additional class and property expansion
@@ -841,11 +857,11 @@
<section>
<h2>Vocabulary Expansion Control of Microdata Processors</h2>
<p>Conforming processors MUST perform vocabulary expansion.</p>
- <p>If vocabulary expansion is performed using [[RDFA-CORE]] voabulary expansion, MUST NOT
- include the vocabulary dereferencing steps unless the <code>vocab_expansion</code>
- option is passed to the microdata processor.</p>
+ <p>If vocabulary expansion is performed using [[RDFA-CORE]] voabulary expansion, and the
+ <code>vocab_expansion</code> option is passed to the microdata processor,
+ the expansion MUST be performed.</p>
<p class="note"> Although vocabulary expansion is described in terms of
- OWL entailment rules, processors
+ OWL2 entailment rules, processors
are free to use any process which obtains equivalent results.</p>
</section>
</section>
@@ -1337,8 +1353,7 @@
<p>If the value is an array, generate a triple for each value of that array.</p>
</li>
<li>If the <a>registry</a> entry for <a>propertyURI</a>
- has an <code>subPropertyOf</code> key, and such a triple has not
- already been generated, generate the following triple using the
+ has an <code>subPropertyOf</code> key, generate the following triple using the
<em>value</em> of that key:
<dl class="triple">
<dt>subject</dt>
@@ -1508,8 +1523,10 @@
@prefix dc: <http://purl.org/dc/terms/> .
@prefix md: <http://www.w3.org/ns/md#> .
@prefix frbr: <http://purl.org/vocab/frbr/core#> .
+@prefix rdfa: <http://www.w3.org/ns/rdfa#> .
-<> md:item (<http://books.example.com/works/45U8QJGZSQKDH8N>) .
+<> md:item (<http://books.example.com/works/45U8QJGZSQKDH8N>) ;
+ rdfa:usesVocabulary frbr: .
<http://books.example.com/works/45U8QJGZSQKDH8N> a frbr:Work ;
dc:creator "Wil Wheaton"@en ;
@@ -1532,19 +1549,19 @@
<!--
<p>
Both
- <span itemscope="" itemtype="http://microformats.org/profile/hcard" itemref="home">
+ <span itemscope itemtype="http://microformats.org/profile/hcard" itemref="home">
<span itemprop="fn"
- ><span itemprop="n" itemscope=""
+ ><span itemprop="n" itemscope
><span itemprop="given-name">Princeton</span></span></span>
</span>
and
- <span itemscope="" itemtype="http://microformats.org/profile/hcard" itemref="home">
+ <span itemscope itemtype="http://microformats.org/profile/hcard" itemref="home">
<span itemprop="fn"
- ><span itemprop="n" itemscope=""
+ ><span itemprop="n" itemscope
><span itemprop="given-name">Trekkie</span></span></span>
</span>
live at
- <span id="home" itemprop="adr" itemscope="">
+ <span id="home" itemprop="adr" itemscope>
<span itemprop="street-address">Avenue Q</span>.
</span>
</p>
@@ -1559,6 +1576,7 @@
<!--
@prefix md: <http://www.w3.org/ns/md#> .
@prefix hcard: <http://microformats.org/profile/hcard#> .
+@prefix rdfa: <http://www.w3.org/ns/rdfa#> .
<> md:item (
[ a <http://microformats.org/profile/hcard>;
@@ -1570,30 +1588,34 @@
hcard:fn "Trekkie";
hcard:n [ hcard:given-name "Trekkie" ];
hcard:adr _:a
- ]) .
+ ]) ;
+ rdfa:usesVocabulary <http://microformats.org/profile/hcard> .
_:a hcard:street-address "Avenue Q" .
-->
</pre>
<p>The following snippet of HTML has microdata for a playlist, and illustrates overriding a property
- to place elements in an RDF Collection:</p>
+ to place elements in an RDF Collection. This also illustrates the use of the <code>schema:additionalType</code>
+ property to relate recordings to the <cite><a href="http://musicontology.com/">Music Ontology</a></cite>:</p>
<pre class="example" data-transform="updateExample">
<!--
-<div itemscope="" itemtype="http://schema.org/MusicPlaylist">
+<div itemscope itemtype="http://schema.org/MusicPlaylist">
<span itemprop="name">Classic Rock Playlist</span>
<meta itemprop="numTracks" content="2"/>
<p>Including works by
<span itemprop="byArtist">Lynard Skynard</span> and
<span itemprop="byArtist">AC/DC</span></p>.
- <div itemprop="tracks" itemscope="" itemtype="http://schema.org/MusicRecording">
+ <div itemprop="tracks" itemscope itemtype="http://schema.org/MusicRecording">
+ <link itemprop="additionalType" href="http://purl.org/ontology/mo/MusicalManifestation"/>
1.<span itemprop="name">Sweet Home Alabama</span> -
<span itemprop="byArtist">Lynard Skynard</span>
<link href="sweet-home-alabama" itemprop="url" />
</div>
- <div itemprop="tracks" itemscope="" itemtype="http://schema.org/MusicRecording">
+ <div itemprop="tracks" itemscope itemtype="http://schema.org/MusicRecording">
+ <link itemprop="additionalType" href="http://purl.org/ontology/mo/MusicalManifestation"/>
2.<span itemprop="name">Shook you all Night Long</span> -
<span itemprop="byArtist">AC/DC</span>
<link href="shook-you-all-night-long" itemprop="url" />
@@ -1611,7 +1633,9 @@
<pre class="example" data-transform="updateExample">
<!--
@prefix md: <http://www.w3.org/ns/md#> .
+@prefix mo: <http://purl.org/ontology/mo/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfa: <http://www.w3.org/ns/rdfa#> .
@prefix schema: <http://schema.org/> .
<> md:item ([ a schema:MusicPlaylist;
@@ -1619,15 +1643,18 @@
schema:byArtist ("Lynard Skynard" "AC/DC");
schema:numTracks "2";
schema:tracks (
- [ a schema:MusicRecording;
+ [ a schema:MusicRecording, mo:MusicalManifestation;
schema:byArtist ("Lynard Skynard");;
schema:name "Sweet Home Alabama";
schema:url <sweet-home-alabama>]
- [ a schema:MusicRecording;
+ [ a schema:MusicRecording, mo:MusicalManifestation;
schema:byArtist ("AC/DC");;
schema:name "Shook you all Night Long";
schema:url <shook-you-all-night-long>]
- )]); .
+ )]);
+ rdfa:usesVocabulary schema: .
+
+schema:additionalType rdfs:subPropertyOf rdf:type .
-->
</pre>