Intelligent Agent and Semantic Web

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Intelligent Agent and Semantic Web
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Intelligent Agents

• Concept

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Intelligent Agents

• Intelligent agent is a software that is
• Autonomous
• Operates without direct intervention
• Proactive self-starting behavior
• Reactive sense and act on environment
• Intelligent
• Adapt to users and environments
• Learn from experience
• Inference using knowledge
• Social
• Cooperate with human and other software agents
• Ability to communicate

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Agent Applications

• Information retrieval/filtering
• Web search - collecting and indexing Web pages
• information gathering meta search, adaptive to
  a user by learning
• Information filtering - filter news/email,
  automatic categorization
• Electronic commerce
• Trading - autonomous bidding agents
• Comparison comparing costs of items from
  multiple shopping sites
• Recommendation identify customer interests and
  recommend items
• Intelligent user interface
• OS agents automatic system management,
  proactive help
• Application agents - automation of complex tasks

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Semantic Web

• Basic concept
• 1999 by W3C
• Provide semantics to information on Web so that
  it can be easily interpreted by computer
• Definitions on the relationship between data
• Automated and integrated information sharing
• RDF/RDFS, DAMLOIL, OWL, RuleML,

Human readable
Machine readable
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HTML (HyperText Markup Language)

• About how to display information
• Not useful for machine search
• Is Introduction to AI a book?
• Who is the author of the Introduction to AI?
• What is the price of the Introduction to AI?

lthtmlgt ltbodygt lth1gtIntroduction to AI lt/h1gt By
ltbgt Juntae Kim lt/bgt - 100.00 lt/bodygt lt/htmlgt
Introduction to AI By Juntae Kim - 100.00
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XML(eXtensible Markup Language)

• About what a data is (structure)
• Help machine to identify data
• W3C recommendation
• Semantic problems
• What is the textbook written by Prof. Juntae Kim
  ?
• Is textbook book ?
• What written by means?
• Is author a person?

lt?XML version1.0?gt ltbookgt
lttitlegtIntroduction to AIlt/titlegt
ltauthorgtJuntae Kimlt/authorgt ltpricegt100.00lt/pri
cegt lt/bookgt
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RDF(Resource Description Framework)

• About describing resources on the Web
• Describe relations between resources (connect
  resources)
• Help machine to understand data (meaning)
• Written in XML, part of Semantic Web activity
• RDF data model
• Resources an object we describe (URI)
• Properties relations between resources
• Statements Resources Properties Values
  (resources or literals)

author
http//www.my.store/book/AI
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RDF(Resource Description Framework)

• Supports labelled directed graphs

author
http//www.my.store/book/AI
ltrdfRDFxmlnsrdf"http//www.w3.org/1999/02/22-r
df-syntax-ns"xmlnsmy"http//www.my.store/my-ns"
gtltrdfDescription rdfabout"http//www.my.store
/AI"gt  ltmyauthorgtJuntae Kimlt/myauthorgt lt/rdfDe
scriptiongtlt/rdfRDFgt
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RDF(Resource Description Framework)

• Defining and linking resources

author
http//www.my.store/book/AI
631010
name
phone
1234-5678
ltrdfDescription rdfID631010gt 
ltmynamegtJuntae Kimlt/mynamegt
ltmyphonegt1234-5678lt/myphonegt lt/rdfDescriptiongt
ltrdfDescription rdfabouthttp//www.my.store/A
Igt  ltmyauthor rdfresource631010/gt lt/rdfDe
scriptiongt
resource
resource
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RDFS(RDF Schema)

• Provides basic ontological primitives
• Define application-specific classes and
  properties
• Class (and property) hierarchy

RDFS
RDF
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RDFS(RDF Schema)
ltrdfsClass rdfIDpersongt ltrdfssubClassOf
rdfresourcehttp//www.w3.org/1999/02/22-rdf-syn
tax-nsResource/gt lt/rdfsClassgt ltrdfsClass
rdfIDprofessorgt ltrdfssubClassOf
rdfresourceperson/gt lt/rdfsClassgt
... ltrdfProperty rdfIDauthorgt
ltrdfsdomain rdfresourcebook/gt
ltrdfsrange rdfresourceperson/gt
lt/rdfPropertygt ... ltrdfDescription
rdfID631010gt ltrdftype rdfresourceprofesso
r  ltmynamegtJuntae Kimlt/mynamegt
ltmyphonegt1234-5678lt/myphonegt lt/rdfDescriptiongt
ltrdfDescription rdfabouthttp//www.my.store/A
Igt  ltmyauthor rdfresource631010/gt lt/rdfDe
scriptiongt
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OWL(The Web Ontology Language)

• Ontology
• Formal, explicit specification of a shared
  conceptualization
• Defines the concepts and relationships used to
  describe and represent an area of knowledge
• Dublin Core (ontology for documents), FOAF
  (friend of a friend), Gene Ontology, Business
  Model Ontology,

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OWL(The Web Ontology Language)

• OWL extends RDF and RDFS
• Bring expressive and reasoning power of logic to
  Semantic Web
• Exgt Specifies property of classes, property of
  properties,

ltowlOntology rdfaboutgt ltowlClass
rdfIDprofessorgt ltrdfssubClassOf
rdfresourceperson/gt ltrdfssubClassOfgt
ltowlRestrictiongt ltowlonProperty
rdfresourceteach/gt
ltowlsomeValueFrom rdfresourcecourse/gt
lt/owlRestrictiongt lt/rdfssubClassOfgt
lt/owlClassgt ... ltowlObjectProperty
rdfIDwritesgt ltowlinverseOf
rdfresourceauthor/gt lt/owlObjectPropertygt lt/o
wlOntologygt
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Applications of Semantic Web

• Intelligent e-commerce
• Intelligent information retrieval
• Automated Web service
• Knowledge management

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LOD(Linking Open Data) Project

• Goal
• Expose open datasets in RDF
• Set RDF links among the data items from different
  datasets
• Altogether billions of triples, millions of
  links
• Exgt DBpedia is a community effort to
• Extract structured information from Wikipedia
• Provide a query endpoint to the dataset
• Interlink the DBpedia dataset with other datasets
  on the Web

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The LOD cloud, 2008/03
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The LOD cloud, 2008/09
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The LOD cloud, 2009/03