The document discusses ontologies and how they can be used to represent knowledge. It provides examples of representing students and universities using XML, RDF, and OWL. The key steps for developing ontologies are also outlined, including determining the domain and scope, reusing existing ontologies, defining classes and properties. Examples are given of querying ontologies using SPARQL and developing agent systems that utilize ontologies.

1. Ontologias
Sérgio Santos
Inteligência Artificial
Novembro 2009
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2. <rdf:RDF
xmlns:rdf="http://www.w3.org/TR/WD-rdf-syntax#"
xmlns="http://dei.uc.pt/works-syntax">
<rdf:Description about="http://dei.uc.pt/works#1337"/>
<Title>
Ontologias
</Title>
Sérgio Santos </Author>
<Author>
<Subject> Inteligência Artificial </Subject>
<PublishDate> Novembro 2009 </PublishDate>
</rdf:RDF>
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4. Como representar
conhecimento?
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5. <?xml version="1.0" encoding="utf-8" ?>
<university name="Universidade de Coimbra" id="504">
<students>
<student name="Sérgio Santos" id="2006125508">
<address>Espinheiro, Penela</address>
<course id="123">
Mestrado em Engenharia Informática
</course>
</student>
...
</students>
</university>
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6. university
student student student
address course
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7. […]
xmlns:uc="http://uc.pt/syntax#"
[…]
<rdf:Description about="http://uc.pt">
<uc:name>Universidade de Coimbra</uc:name>
</rdf:Description>
<rdf:Description about="http://dei.uc.pt/~sdsantos">
<uc:name>Sérgio Santos</uc:name>
<uc:num>2006125508</uc:num>
<uc:attendsCourse rdf:resource="http://dei.uc.pt/~MEI" />
<uc:attendsUniversity rdf:resource="http://uc.pt" />
</rdf:Description>
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8. http://dei.uc.pt/~sdsantos
student
attendsUniversity attendsCourse
university course
http://uc.pt http://dei.uc.pt/~MEI
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9. http://uc.pt/syntax
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#">
<rdfs:Class rdf:ID="student"/>
<rdfs:Class rdf:ID="university"/>
<rdfs:Class rdf:ID="course"/>
</rdf:RDF>
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xmlns="http://uc.pt/syntax#"
[…]
<university rdf:id="UC">
<name>Universidade de Coimbra</name>
</university>
<student rdf:id="sdsantos">
<name>Sérgio Santos</name>
<num>2006125508</num>
<attendsCourse rdf:resource="#MEI" />
<attendsUniversity rdf:resource="#UC" />
</student>
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12. <owl:Ontology rdf:about="">
<rdfs:comment>Example ontology.</rdfs:comment>
</owl:Ontology>
<owl:Class rdf:ID="Person">
<rdfs:subClassOf rdf:resource="http://www.w3.org/2002/07/owl#Thing"/>
</owl:Class>
<owl:Class rdf:ID="Student">
<rdfs:subClassOf rdf:resource="#Person"/>
</owl:Class>
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20. Trabalhar com
ontologias
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21. 1. Determinar o domínio e abrangência da ontologia
2. Considerar a reutilização de ontologias existentes
3. Enumerar os termos importantes na ontologia
4. Definir as classes e a sua hierarquia
5. Definir as propriedades das classes
6. Definir os tipos de propriedades
7. Criar os indivíduos
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26. String personURI = "http://somewhere/JohnSmith";
String givenName = "John";
String familyName = "Smith";
String fullName = givenName + " " + familyName;
Model model = ModelFactory.createDefaultModel();
Resource johnSmith = model.createResource(personURI)
.addProperty(VCARD.FN, fullName)
.addProperty(VCARD.N, model.createResource()
.addProperty(VCARD.Given, givenName)
.addProperty(VCARD.Family, familyName));
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27. public class SomeClientAgent extends Agent
implements SomeVocabulary
{
private Codec codec = new SLCodec();
private Ontology ontology = SomeOntology.getInstance();
protected void setup() {
// Register language and ontology
getContentManager().registerLanguage(codec);
getContentManager().registerOntology(ontology);
...
}
...
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29. PREFIX uc: <http://uc.pt/syntax#>
SELECT ?aluno
FROM <studentsDB.rdf>
WHERE {
?aluno uc:attendsUniversity "#UC" .
?aluno uc:attendsCourse "#MEI" .
}
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31. Knowledge
Portals
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37. ^
Referencias
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