Intro to Knowledge Engineering_VG
-
Upload
arman-azmi -
Category
Documents
-
view
218 -
download
0
Transcript of Intro to Knowledge Engineering_VG
-
8/13/2019 Intro to Knowledge Engineering_VG
1/11
Introduction to KnowledgeEngineering
Ontology , Knowledge Base
GMU IT344 Fall 2013Prof. Vera Goodacre
-
8/13/2019 Intro to Knowledge Engineering_VG
2/11
What is Ontology ?
Philosophical senseWhat is existence?What are the meanings of being ?Into what categories can we divide existingthings ?
Computer science
Computational models that enable certain kind ofautomated reasoning
IT344 Vera Goodacre 2
-
8/13/2019 Intro to Knowledge Engineering_VG
3/11
IT344 Vera Goodacre 3
Database versus Knowledge base
Databasedefines data andvia conceptual schema relations on dataData is expressible in ground atomic facts
Ontology (Knowledge base)Defines terms with which to represent knowledge
Ontology defines its vocabulary and builds on itKnowledge can be expressed with logicalsentences and variables
-
8/13/2019 Intro to Knowledge Engineering_VG
4/11
Ontology / Knowledge Base
IT344 Vera Goodacre 4
Property types for the relation type Employment(employed-by)
From Helsinki University of Technology TAI research center
-
8/13/2019 Intro to Knowledge Engineering_VG
5/11
Ontology / Knowledge Base
IT344 Vera Goodacre 5
Knowledge is presented as instances of concepts From HUT TAI research center
-
8/13/2019 Intro to Knowledge Engineering_VG
6/11
IT344 Vera Goodacre 6
Ontology / Knowledge Base
Ontology isSpecification of a representational vocabulary for aspecific domain
Study of category of things that may exist in somedomainKey challenge
How to share knowledge between domains
Attempts to formalize approach to building ontologies :KIF Knowledge Interface FormatLisp like notation
-
8/13/2019 Intro to Knowledge Engineering_VG
7/11
Example : Vehicle ontology
IT344 Vera Goodacre 7
From Basic Ontology Processes
-
8/13/2019 Intro to Knowledge Engineering_VG
8/11
Ontology processes
How to process knowledge in the ontologyElaboration
Uses inheritance (upward search to get
information)ElicitationDownward search to get information for aspecific node
Information RetrievalLocate a node and information from itsneighborhood
IT344 Vera Goodacre 8
-
8/13/2019 Intro to Knowledge Engineering_VG
9/11
Ontology processes
IT344 Vera Goodacre 9
From Basic Ontology Processes
-
8/13/2019 Intro to Knowledge Engineering_VG
10/11
Advanced Ontology processes
Dynamic IntegrationPropagates the new information via several nodes
Classification , generalization
Ontology based inferencesThe ultimate goal of field of automated reasoningis to model and emulate human thinking processes.The basis for any inference process is a formal
system, ontology provides such example - used inKnowledge Acquisition systems
IT344 Vera Goodacre 10
-
8/13/2019 Intro to Knowledge Engineering_VG
11/11