文档介绍：Fuzzy Description Logics and the Semantic Web
Umberto ia
ISTI - CNR, Pisa ITALY
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Bari 2006
“Calla is a very large, long white flower on thick stalks”
U. ia (ISTI - CNR) Fuzzy DLs Bari 2006 1 / 83
Outline
1 The Semantic Web and Ontologies
The Semantic Web Vision
Ontologies
2 Description Logics
DLs Basics
3 Fuzzy Description Logics
A clarification: Uncertainty . Imprecision
Examples of applications
Top-k retrieval in DLs
Propositional Fuzzy Logics Basics
Predicate Fuzzy Logics Basics
Fuzzy DLs Basics
Towards fuzzy OWL Lite and OWL DL
U. ia (ISTI - CNR) Fuzzy DLs Bari 2006 2 / 83
The Semantic Web and Ontologies (excerpt)
U. ia (ISTI - CNR) Fuzzy DLs Bari 2006 3 / 83
The Semantic Web Vision
The w it now
I 1st generation web mostly handwritten HTML pages
I 2nd generation (current) web often machine generated/active
I Both intended for direct human processing/interaction
In next generation web, resources should be more accessible to
automated processes
I To be achieved via semantic markup
I Metadata annotations that describe content/function
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Ontologies
Semantic markup must be meaningful to automated processes
Ontologies will play a key role
I Source of precisely defined terms (vocabulary)
I Can be shared across applications (and humans)
Ontology typically consists of:
I Hierarchical description of important concepts in domain
I Descriptions of properties of instances of each concept
Ontologies can be used, .
I To facilitate agent-munication in merce
I In semantic based search
I To provide richer service descriptions that can be more flexibly
interpreted by intelligent agents
U. ia (ISTI - CNR) Fuzzy DLs Bari 2006 5 / 83
Example Ontology
Vocabulary and meaning (“definitions”)
I Elephant is a concept whose members are a kind of animal
I Herbivore is a concept whose members are exactly those animals
who eat only plants or parts o