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UML Notations for Ontology Elements

3.3.1 Ontology Document

Semantic mapping requires one or more ontology documents that describe vocabularies [OWL Overview] of a specific domain. This ontology document notation distinguishes the ownership of the ontology elements.

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 Package::ownedMember classifier - represents an ontology document and a vocabulary that is described in the document.

 First part of the classifier separated by a double colon (‘::’) - represents the name of the ontology document.

Graphical Representation

Package::ownedMember classifier in the name field of UML::Class and UML::Association is used to represent an ontology document. Fig. 3-6 shows the UML notations that represent ‘Device’, ‘Cable’, and ‘hasInterface’ ontology vocabularies, which are described in ‘Network’ ontology document.

Figure 3-6 UML notation example for ontology document

3.3.2 Ontology Class

Ontology class defines a group of individuals that belong together because they share some properties [OWL Overview]. For example, ‘femtocell1’ and ‘femtocell2’ are both members of the class ‘Femto’. Ontology vocabularies can be aligned into a collection of triples, i.e. RDF statement [RDF Concepts], each consisting of a subject, a predicate and an object. An ontology class can be a subject or an object in the statement.

UML Notation

 UML::Class - represents an ontology class.

 Second part of the classifier in the name field of UML::Class separated by a double colon (‘::’) - represents the name of the ontology class.

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UML::Class is used to represent an ontology class. Fig. 3-7 shows the UML notation that represents the ontology class ‘Femto’.

Figure 3-7 UML notation example for ontology class

Fig. 3-8 shows the UML notations which each notation corresponds to each node in RDF statement, i.e. Subject (Femto) - Predicate (hasNPM) - Object (NPM).

Figure 3-8 UML notation example for RDF statement

3.3.3 Ontology Individual

An individual is an instance of a class, and properties may be used to relate one individual to another [OWL Overview]. For example, an individual named ‘femtocell1’ may be described as an instance of the class ‘Femto’ and the property ‘hasNPM’ may be used to relate the individual ‘femtocell1’ to the individual ‘networkdata1’. An ontology individual can be a subject or an object in a RDF statement.

UML Notation

 UML::InstanceSpecification - represents an ontology individual.

 First part of the classifier in the name field of UML::InstanceSpecification separated by a colon (‘:’) - represents the name of the individual.

 Second part of the classifier in the name field of UML::InstanceSpecification separated by a colon (‘:’) - represents the ontology document and class name

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of the individual that has this class extension. The individuals in the class extension are called the instances of the class.

Graphical Representation

UML::InstanceSpecification is used to represent an ontology individual. Fig. 3-9 shows the UML notation that represents the ontology individual ‘femtocell1’ of the ontology class ‘Femto’.

Figure 3-9 UML notation example for ontology individual

Fig. 3-10 shows the UML notations which each notation corresponds to each node in a RDF statement, i.e. Subject (femtocell1) - Predicate (hasNPM) - Object (networkdata1).

Figure 3-10 UML notation example for RDF statement

3.3.4 Ontology Object Property

Ontology object property can be used to state relationships between instances of two classes [OWL Guide]. For example, the object property ‘hasInterface’ can be used to relate an instance of the class ‘Device’ to an instance of the class ‘Cable’. An ontology object property can be a predicate in a RDF statement, and there should be classes or individuals as a subject and an object.

UML Notation

 UML::Association - represents an ontology object property. The property links from a subject to an object with unidirectional navigation.

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 Second part of the classifier in the name field of UML::Association separated by a double colon (‘::’) - represents the name of the ontology object property. Graphical Representation

UML::Association is used to represent an ontology object property. Fig. 3-11 shows the UML notation that represents the ontology object property ‘hasInterface’.

Figure 3-11 UML notation example for ontology object property

Fig. 3-12 shows the UML notations which each notation corresponds to each node in a RDF statement, i.e. Subject (router1) - Predicate (hasInterface) - Object (rj45).

Figure 3-12 UML notation example for RDF statement

3.3.5 Ontology Datatype Property

Ontology datatype property can be used to state relationships between instances of classes and RDF literals and XML schema data types [XML Datatype][OWL Guide]. For example, the datatype property ‘successRate’ can be used to relate an instance of the class ‘Femto’ to a value of the data type ‘double’. An ontology datatype property can be a predicate in RDF statement, and there should be a RDF literal or XML Schema data type as an object.

UML Notation

 UML::Property - represents an ontology datatype property.

 Second part of the classifier in the property name separated by a double colon (‘::’) - represents the name of the ontology datatype property.

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UML::Property is used to represent an ontology datatype property. Fig. 3-13 shows the UML notation that represents the ontology datatype property ‘successRate’.

Figure 3-13 UML notation example for ontology datatype property

Fig. 3-14 shows the UML notation which each element: Instance name, Property name and Property value, corresponds to each node in a RDF statement, i.e. Subject (femtocell1) - Predicate (successRate) - Value (90.0)

Figure 3-14 UML notation example for RDF statement

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