GitLab upgrade completed. Current version is 17.10.3. We now benefit from the enhancements of 17.9 and 17.10 releases. Among other improvements, it is now possible to set the automatic deletion of continuous integration pipelines. You can help us reduce storage usage by setting an expiry date for your pipelines.
<p>Representing ontology alignments is the general purpose of this vocabulary. Particularly, it extends the ontology <ahref="format.html">alignment format</a> in order to enable the representation of complex correspondences.</p>
<p>Representing ontology alignments is the general purpose of this vocabulary. Particularly, it extends the ontology <ahref="format.html">alignment format</a> in order to enable the representation of complex correspondences.</p>
<p>This format can be used for cases where expressing equivalence or subsumption between terms is not sufficient, when more precise relations need to be expressed. While term equivalence or subsumption might be enough for exchanging documents, more precise relations are needed to exchange and integrate data.</p>
<p>This format can be used for cases where expressing equivalence or subsumption between terms is not sufficient, when more precise relations need to be expressed. While term equivalence or subsumption might be enough for exchanging documents, more precise relations are needed to exchange and integrate data.</p>
...
@@ -46,11 +48,17 @@ the <a href="format.html">alignment format</a>.</p>
...
@@ -46,11 +48,17 @@ the <a href="format.html">alignment format</a>.</p>
<p>This vocabulary was originally designed with the goal of representing patterns of correspondence between ontologies. It was since then both simplified and extended to obtain a minimal vocabulary on top of the alignment format, able to express all possible kinds of ontology alignments.</p>
<p>This vocabulary was originally designed with the goal of representing patterns of correspondence between ontologies. It was since then both simplified and extended to obtain a minimal vocabulary on top of the alignment format, able to express all possible kinds of ontology alignments.</p>
<h2id="sec:features">Features</h2>
<h2id="sec:features">Features</h2>
The alignment vocabulary has the following features:
The alignment vocabulary has the following features:
<ul>
<ul>
<li><b>Construction</b> of entities from other entities can be expressed through
algebraic operators. Constructed entities allows to supply the
shallowness of some ontologies.</li>
<li><b>Restrictions</b> can be expressed on entities in order to narrow their scope. Narrowing the scope of an entity makes possible to better align this entity with the one corresponding in the other ontology.</li>
<li><b>Restrictions</b> can be expressed on entities in order to narrow their scope. Narrowing the scope of an entity makes possible to better align this entity with the one corresponding in the other ontology.</li>
<li><b>Transformations</b> of property values can be specified. Property values using different encoding or units can be aligned using transformations.</li>
<li><b>Transformations</b> of property values can be
<li><b>Properties composition</b> can be expressed to target values through a path of properties.</li>
specified. Property values using different encoding or units can be
aligned using transformations. The current version of Edoal only
supports a limited kind of transformations. This will be improved soon.</li>
</ul>
</ul>
<h2id="sec:vocabulary">Vocabulary</h2>
<h2id="sec:vocabulary">Vocabulary</h2>
...
@@ -65,7 +73,7 @@ The diagram below shows the vocabulary classes ???
...
@@ -65,7 +73,7 @@ The diagram below shows the vocabulary classes ???
</p>
</p>
<p>
<p>
While <i>Alignment</i> and <i>Cell</i> are described by the alignment format, we will focus here on the remaining classes.</p>
While <i>Alignment</i> and <i>Cell</i> are described by the <ahref="format.html">alignment format</a>, we will focus here on the remaining classes.</p>
<h3id="ssec:headers">Headers</h3>
<h3id="ssec:headers">Headers</h3>
...
@@ -76,7 +84,7 @@ still <tt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#</tt>
...
@@ -76,7 +84,7 @@ still <tt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#</tt>
(usual prefix: align).
(usual prefix: align).
</p>
</p>
<p>
<p>
EDOAL's own namespace is <tt>http://ns.inria.org/edoal/</tt> (usual
EDOAL's own namespace is <tt>http://ns.inria.org/edoal/1.0/</tt> (usual
<p>As specified by the alignment format, an alignment contains a set of correspondences (cells). Each cell can be linked to an alignment using the <i>map</i> property. The alignment moreover specifies the two aligned ontologies, and as exemplified in the code below.</p>
<p>As specified by the alignment format, an alignment contains a set of correspondences (cells). Each cell can be linked to an alignment using the <i>map</i> property. The alignment moreover specifies the two aligned ontologies, and as exemplified in the code below.</p>
<p>Details on each property are available on the <ahref="format.html">alignment format</a> page.</p>
<p>Details on each property are available on the <ahref="format.html">alignment format</a> page.</p>
...
@@ -116,9 +141,43 @@ not</i>.<ul>
...
@@ -116,9 +141,43 @@ not</i>.<ul>
A class can be defined using its URI or a restriction. Restrictions are defined by giving an <i>attribute</i> (relation or property), a <i>comparator</i> defining the relation to a <i>value</i>.</p>
A class can be defined using its URI or a restriction. Restrictions are defined by giving an <i>attribute</i> (relation or property), a <i>comparator</i> defining the relation to a <i>value</i>.</p>
<p>Transformations are of two kinds, either XPath transformation functions can be used, or other transformation services can be invoked, for example for dynamic transformations like currency conversions (see <ahref="#sec:examples">examples</a>).</p>
<p>Transformations are of two kinds, either XPath transformation functions can be used, or other transformation services can be invoked, for example for dynamic transformations like currency conversions (see <ahref="#sec:examples">examples</a>).</p>
<h4id="ssec:relations">Relations</h4>
<h4id="ssec:relations">Relations</h4>
<p>Relations correspond to object properties in OWL. Relation entities can be constructed using the operators <i>and, or,
<p>Relations correspond to object properties in OWL. Relation entities can be constructed using the operators <i>and, or,
not</i>, but also <i>inverse, transitive, reflexive,</i> and <i>symmetric</i>. Like properties they can also be composed in a path of relations using <i>first</i> and <i>next</i>. Relations <i>domain</i> and <i>range</i> can be restricted.</p>
not, compose</i>, but also <i>inverse, transitive, reflexive,</i> and <i>symmetric</i>. Like properties they can also be composed in a path of relations using <i>first</i> and <i>next</i>. Relations <i>domain</i> and <i>range</i> can be restricted.</p>
<p>Variables are useful to represent alignment patterns. (see <ahref="#ssec:ex4">Example 4</a>) A variable can be linked to an identifier string, and can be bounded to an entity.</p>
<divclass="fragment"><pre>
variable ::= <Variable>
<var_id>string</var_id>
<var_binding rdf:resource="uri"/>
</Variable>
</pre></div>
</pre></div>
<h2id="sec:examples">Examples</h2>
<h2id="sec:examples">Examples</h2>
<p>The following exmples illustrate various kids of usage of the vocabulary.</p>
<p>The following exmples illustrate various kids of usage of the vocabulary.</p>
<h3id="ssec:ex1">Class partition</h3>
<h3id="ssec:ex1">Class partition</h3>
<p>This example shows how to express a correspondence between a classes in one ontology corresponding to a set of classes in the other ontology. In order to graps the precise correspondence, the one class is partitioned according to the value of one of its attributes. In this example one ontology has a class LED which has a property color, while the other ontology has three classes RedLED, BlueLED, and GreenLED. The LED class is aligned with the three corresponding classes by specifying a restriction of its scope to the corresponding value of the <i>color</i> attribute.</p>
<p>This example shows how to express a correspondence between a classes in one ontology corresponding to a set of classes in the other ontology. In order to graps the precise correspondence, the one class is partitioned according to the value of one of its attributes. In this example one ontology has a class LED which has a property color, while the other ontology has three classes RedLED, BlueLED, and GreenLED. The LED class is aligned with the three corresponding classes by specifying a restriction of its scope to the corresponding value of the <i>color</i> attribute.</p>
<!--The following figure illustrates the alignment:</p>
<!--The following figure illustrates the alignment:</p>
...
@@ -236,54 +321,56 @@ variable ::= <Variable>
...
@@ -236,54 +321,56 @@ variable ::= <Variable>
<p>The alignment expressed in RDF/N3 is the following:</p>
<p>The alignment expressed in RDF/N3 is the following:</p>
<h3id="ssec:ex2">Property value transformation (XPath function)</h3>
<h3id="ssec:ex2">Property value transformation (XPath function)</h3>
<p>This exemple shows how to use a transformation between property values. Two cases can be considered: static transformations such as unit conversion, and transformations which vary over time such as currency conversions. This example illustrates a static conversion from pounds to kilograms using a XPath function.</p>
<p>This exemple shows how to use a transformation between property values. Two cases can be considered: static transformations such as unit conversion, and transformations which vary over time such as currency conversions. This example illustrates a static conversion from pounds to kilograms using a XPath function.</p>
<divclass="detail"id="ex2n3"><pre>
<divclass="detail"id="ex2n3"><pre>
01:hasWeight a align:Property.
01:hasWeight a edoal:Property.
O2:weight a align:Property.
O2:weight a edoal:Property.
:cell a align:Cell;
:cell a align:Cell;
align:entity1 O1:hasWeight;
align:entity1 O1:hasWeight;
align:entity2 [
align:entity2 [
...
@@ -296,22 +383,25 @@ O2:weight a align:Property.
...
@@ -296,22 +383,25 @@ O2:weight a align:Property.
].
].
</pre></div>
</pre></div>
<p>The corresponding graph:</p>
<p>The corresponding graph:</p>
<center>
<!--<img src="graph-property-value-xpath-transformation-small.png" border="0" alt="RDF graph of a property value transformation using a XPath function">-->
<!--<img src="graph-property-value-xpath-transformation-small.png" border="0" alt="RDF graph of a property value transformation using a XPath function">-->
<h3id="ssec:ex4">Class with attribute value restriction</h3>
<h3id="ssec:ex4">Class with attribute value restriction</h3>
<p>This alignment pattern makes use of three variables. Var3 is a property variable representing a property having in its domain the class of the class variable Var1. Morover, the property Var3 has an interger value. This pattern thus captures all correspondences between two classes, the scope of one class being restricted to only those instances having a specific value (not specified by the pattern) for one of its property whith datatype "integer".</p>
<p>This alignment pattern makes use of three variables. Var3 is a property variable representing a property having in its domain the class of the class variable Var1. Morover, the property Var3 has an interger value. This pattern thus captures all correspondences between two classes, the scope of one class being restricted to only those instances having a specific value (not specified by the pattern) for one of its property whith datatype "integer".</p>
EDOAL also contains a pattern language with allows for expressing
generalised correspondences in which entities can be abstract. This
language is not very different from EDOAL (beside its introduction of
variables).
</p>
<p>
It will be released at a later stage. Ask François Scharffe
for a more complete description of the EDOAL Pattern language.
</p>
<!--h3 id="ssec:variables">Variables</h3>
<p>Variables are useful to represent alignment patterns. (see <a href="#ssec:ex4">Example 4</a>) A variable can be linked to an identifier string, and can be bounded to an entity.</p>
<div class="fragment"><pre>
variable ::= <Variable>
<var_id>string</var_id>
<var_binding rdf:resource="uri"/>
</Variable>
</pre></div-->
<h2>History</h2>
<p>
This language has been first designed by François Scharffe as
the SEKT Mapping language.
</p>
<p>
It then became the <ahref="http://www.omwg.org/TR/d7/rdf-xml-syntax/">OMWG Ontology Mapping language</a> developed under the
Sourceforge mappingapi project
(<ahref="http://sourceforge.net/projects/mediation/">http://sourceforge.net/projects/mediation/</a>). This
language was further described by François Scharffe,
Jérôme Euzenat and Antoine Zimmermann
in <ahref="ftp://ftp.inrialpes.fr/pub/exmo/reports/kweb-2210.pdf">Knowledge
web deliverable 2.2.10</a>, in particular through the semantics of
the language. Its implementation was also reengineered as an extension
of the <ahref="format.html">alignment format</a> so that it could be
manipulated through the Alignment API tools (starting version 3.1).
</p>
<p>
It has now been redesigned and reimplemented under the name of
EDOAL. It is a plain component of the Alignment API and is maintained
