Knowledge Representation Part VII Protg / RDFS / OWL / ++ Much of - - PowerPoint PPT Presentation
Knowledge Representation Part VII Protg / RDFS / OWL / ++ Much of the content of this presentation has been copied from: A Practical Guide To Building OWL Ontologies Using Protg 4 and CO-ODE Tools Edition 1.3, Matthew Horridge Jan
1
Jan Pettersen Nytun, UiA Much of the content of this presentation has been copied from: A Practical Guide To Building OWL Ontologies Using Protégé 4 and CO-ODE Tools Edition 1.3, Matthew Horridge
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 2
S O
P
types of properties:
– Object properties. – Datatype properties.
Annotation properties can be used to add metadata (data about data).
Knowledge Representation Part II, JPN, UiA
3
S O
P
Knowledge Representation Part III, JPN, UiA
4
S O
P
B then its inverse property will link individual B
to individual A.
inverse property we can infer that Jean hasChild Matthew.
Knowledge Representation Part III, JPN, UiA
5
S O
P
literal to a subject.
Knowledge Representation Part III, JPN, UiA
6
E.g., it is only possible to have one birth mother
S O
P
Mapping functional property to UML: It is possible to define an association as functional by specifying the upper multiplicity of the navigable end as being 0..1
Knowledge Representation Part III, JPN, UiA
7
Person Female
hasBirthMother isBirthMotherTo 0..1 *
S O
P
that the inverse property is functional.
Knowledge Representation Part III, JPN, UiA
8
S O
P
Functional / Inverse Functional Properties
JPN, UiA
9
Person Female
hasBirthMother isBirthMotherTo 0..1 *
Inverse Functional Property Functional Property
Inverse functional properties are similar, but in the reverse direction.
S O
P
Functional / Inverse Functional Properties continues …
declared as "functional“ but only object properties
can be decleared to be “functional inverse”.
10
S O
P
If a property is transitive, and the property relates individual a to individual b, and also individual b to individual c, then we can infer that individual a is related to individual c via property P. E.g., subRegionOf
JPN, UiA
11
S O
P
If a property P is symmetric, and the property relates individual a to individual b then individual b is also related to individual a via property P. E.g., hasSibling
JPN, UiA
12
S O
P
More Property Characteristics
If a property P is asymmetric, and the property relates individual a to individual b then individual b cannot be related to individual a via property P. E.g., isMotherTo
JPN, UiA
13
S O
P
A property P is said to be reflexive when the property must relate individual to itself. E.g., hasRelative (everybody has himself as a relative).
This does not necessarily mean that every two individuals which are related by a reflexive property are identical.
JPN, UiA
14
S O
P
Irreflexive, meaning that no individual can be related to itself by such a role. E.g., hasParent
Knowledge Representation Part III, JPN, UiA
15
parentOf
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 16
S O
P
[4]: In OWL classes are built up of descriptions that specify the conditions that must be satisfied by an individual for it to be a member of the class.
Jan Pettersen Nytun, UiA, page 17
S O
P
– Quantifier Restrictions
– Cardinality Restrictions – hasValue Restrictions
Jan Pettersen Nytun, UiA, Ontologies, page 18
S O
P
based on the relationships that members of the class participate in.
Jan Pettersen Nytun, UiA, Ontologies, page 19
S O
P
– Existential restrictions – some Describe classes of individuals that participate in at least one relationship along a specified property to individuals that are members of a specified class. – Universal restrictions – only Describe classes of individuals that for a given property only have relationships along this property to individuals that are members of a specified class.
Jan Pettersen Nytun, UiA, Ontologies, page 20
S O
P
New version of Protégé calls it “Subclass of”
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 22
A restriction containing an
describes a class of all individuals for which at least one value of the property concerned is an instance of the class description or a data value in the data range.
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 23
Cardinality in dialog window should be ignored (it is 1..*)
S O
P
pizza:Pizza rdf:type owl:Class ; rdfs:label "Pizza"@en ; rdfs:subClassOf [ rdf:type owl:Restriction ;
] ; …
Jan Pettersen Nytun, UiA, page 24
At least one pizza base!
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 25
S O
Ppizza:Margherita rdf:type owl:Class ;
rdfs:label "Margherita"@pt ; rdfs:subClassOf pizza:NamedPizza , [ rdf:type owl:Restriction ;
pizza:TomatoTopping ) ] ] , … Only = owl:allValuesFrom
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 27
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 28
There is no “+” for adding; conditions comes from superclass!
S O
P
Jan Pettersen Nytun, UiA, Ontologies, page 29
:Pizza rdf:type owl:Class ; rdfs:subClassOf [ rdf:type owl:Restriction ;
] , [ rdf:type owl:Restriction ;
] .
S O
P
Jan Pettersen Nytun, UiA, Propositional Calculus, page 30
[1] Book: David Poole and Alan Mackworth, Artificial Intelligence: Foundations of Computational Agents, Cambridge University Press, 2010, http://artint.info/ [2] http://www.w3.org/TR/swbp-n-aryRelations/ [3] RDF 1.1 Primer, W3C Working Group Note, 24 June 2014 [4] A Practical Guide To Building OWL Ontologies Using Protégé 4 and CO-ODE Tools Edition 1.3, Matthew Horridge [5] http://www.w3.org/TR/2009/REC-owl2-syntax-20091027/