semantic web
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Semantic Web. Applications Lecture XIV Dieter Fensel. Today’s lecture. Today‘s lecture. Applications for data integration (Piggy Bank, Nepomuk ) Applications for knowledge management (SWAML) Applications for Semantic Indexing and Semantic Portals (Watson) - PowerPoint PPT PresentationTRANSCRIPT
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Semantic WebApplications
Lecture XIV Dieter Fensel
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Today’s lecture
# Date Title
1 Introduction
2 Semantic Web Architecture
3 RDF and RDFs
4 Web of hypertext (RDFa, Microformats) and Web of data
5 Semantic Annotations
6 Repositories and SPARQL
7 OWL
8 RIF
9 Web-scale reasoning
10 Social Semantic Web
11 Ontologies and the Semantic Web
12 SWS
13 Tools
14 Applications
15 Exam
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Today‘s lecture
– Applications for data integration (Piggy Bank, Nepomuk )– Applications for knowledge management (SWAML)– Applications for Semantic Indexing and Semantic Portals
(Watson)– Applications for meta-data annotation and enrichment and
semantic content management (DBPedia)– Applications for description, discovery and selection (Search
Monkey)
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Applications for Data Integration
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Applications for Data Integration
• One of the main advantages of semantic technology is the interoperability of the used information
• That implies many different data sources• Applications for data integration allow the use of cross
source queries and merged view on the different information
• Example applications: – Piggy Bank– NEPOMUK the social Semantic desktop
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Piggy Bank - What is it?
• Firefox Extension• Transforms browser into
mashup platform• Allows to search and
exchange the collected information
• Developed as part of the Simile Project
• Current version: 3.1
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*)
*) Source: http://simile.mit.edu/wiki/Piggy_Bank
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Piggy Bank – How does it work?
• Piggy Bank uses RDF• If a Web page links to RDF,
information is simply retrieved• Otherwise, information is
extracted from the raw content• RDF information is stored
locally• Information can now be
searched, tagged, browsed, etc.
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Piggy Bank – Features at a glance
• Collect data (different plugins, so called Screen Scrapers for information retrieval available)
• Save data for further use• Tag data to add additional
information for more efficient use• Browse and search through
stored information • Share the collected data by
publishing it onto Semantic Bank
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Piggy Bank – Architecture overview
• Firefox 2.0 as application plattform
• Chrome additions, e.g. menu commands, toolbars etc.
• XPCOM components bridging the chrome part and the Java part
• Java Backend for managing the collected information
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NEPOMUK– What is it?
• Nepomuk, The Social Semantic Desktop
• Nepomuk is an acronym for Networked Environment for Personal Ontology-based Management of Unified Knowledge
• It is a set of methods, tools and data structures to extend the personal computer into
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*) Source: http://nepomuk.semanticdesktop.org/xwiki/bin/view/Main1/
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NEPOMUK - Aspects
• Desktop Aspect – tools for annotating and linking information on lokal desktop
• Social Aspect – tools for social relation building and knowledge exchange
• Community Uptake – build a community around the Social Semantic Desktop in order to use the full potential
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NEPOMUK – Projects on Top
• SemanticDesktop.org (developer and user community on the topics of a „Social Semantic Desktop“)
• NEPOMUK KDE (creating a semantic KDE environment)
• NEPOMUK Eclipse (enabling a semantic P2P Semantic Eclipse Workbench)
• NEPOMUK Mozilla (annotate Web data and emails)
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NEPOMUK – Ontologies used (excerpt)
• NAO – NEPOMUK Annotation Ontology for annotating resources
• NIE – NEPOMUK Information Element set of ontologies for describing information elements
– NFO – NEPOMUK File Ontology for describing files and other desktop resources
– NCO - NEPOMUK Conctact Ontology for describing contact information
– NMO – NEPOMUK Message Ontology for describing emails and instant messages
• PIMO – Personal Information Model Ontology for describing personal information
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Applications for Knowledge Management
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Applications for Knowledge Management
• Simply storing or organizing information is not enough to turn information into knowledge
• Knowledge is applied information• Unless people are able apply to a task information that knowledge is
useless• Frequently collective knowledge • Example application: SWAML
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SWAML – What is it?
• Mailinglist store vast knowledge capital
• Major drawbacks: hard to query, unstructured, difficult to work with
• SWAML generates RDF from mailing list archives, consequently
• Developed by CTIC Foundation and the WESO-RG at University of Oviedo
• Current version: 0.1.0
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SWAML – How does it work?
• mbox as data source• SWAML core produces RDF
data ; SIOC ontology used• Enrichment of stored data with
FOAF using Sindice (Semantic Web Index) as source of infromation
• Access and use stored semantic data via Buxon browser
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SWAML – The SIOC Ontology
• SIOC is an acronym for Semantically-Interlinked Online Communities
• Main objective: – to structure information of
community based sites– Link information of
community based sites• Consists of several classes
and properties to describe community sites (weblogs, message boards, etc.)
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*)
*) Source: http://rdfs.org/sioc/spec/
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Applications for Semantic Indexing and Semantic Portals
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Applications for Semantic Indexing and Semantic Portals
• Web already offers topic-specifigc portals and generic structured directories like Yahoo! or DMOZ
• With semantic technologies such portals could:– use deeper categorization and use ontologies– integrate indexed sources from many locations and communities– provide different structured views on the underlying information
• Example application: Watson
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Watson – What is it?
• Watson is a gateway for the semantic web
• Provides efficient access point to the online ontologies and semantic data
• Is developed at the Knoledge Media Institute of the Open Universit in Milton Keynes, UK
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*) Source: http://watson.kmi.open.ac.uk/Overview.html
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Watson – How does it work?
• Watson collects available semantic content on the Web
• Analyzes it to exstract useful metadata and indexes it
• Implements efficient query facilities to acess the data
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*) Source: http://watson.kmi.open.ac.uk/Overview.html
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Watson – Features at a Glance
• Attempt to provide high quality semantic data by ranking available data
• Efficient exploration of implicit and explicit relations between ontologies
• Selecting only relevant ontology modules by extraciting it from the whole ontology
• Different interfaces for querying and navigation as well as different levels of formalization
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Watson – An example
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Search for movie and directorSearch for movie and director Resulting ontologiesResulting ontologies
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Applications for meta-data annotation and enrichment and semantic content management
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Applications for meta-data annotation and enrichment and semantic content management
• Applications that focus on adding, generating and managing meta-data of existing information
• Often collaborative applications like Wikis with semantic capabilities
• Example applications: SemanticMediaWiki, DBpedia
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DBpedia – What is it?
• Approach to extract structured information from Wikipedia
• Huge knowledge database consisting of more than 274 million RDF triples
• Allows advanced queries against the stored information
• Is maintained by Freie Universität Berlin and Universität Leipzig
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*) Source: http://wiki.dbpedia.org/About
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Dbpedia – How does it work?
• Wikipedia contains structured information like infoboxes, categorizations, etc.
• DBpedia extracts this kinds of structured information and transforms it into RDF-statements . This is done by the Dbpedia Information Extraction Framework
• Provides a SPARQL-endpoint to access and query the data
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The DBpedia Ontology
• DBpedia Ontology is used to extract data from infoboxes
• Consists of more than 170 classes and 940 properties
• Manual mappings from infobox to the Ontology define fine-granular rules how to parse infobox-values
• Does not cover all Wikipedia infobox and infobox properties
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DBpedia – A query example
• SPARQL Query that finds people who were born in Innsbruck before 1900
• Search with regular search mechanism virtually impossible
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Applications for description, discovery and selection
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Applications for description, discovery and selection
• Category of applications the are closely related to semantic indexing and knowledge management
• Applications mainly for helping users to locate a resource, product or service meeting their needs
• Example application: SearchMonkey
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SearchMonkey – What is it?
• Search monkey is a framework for creating small applications that enhance Yahoo! Search results
• Additional data, structure, images and links may be added to search results
• Yahoo provides meta-data
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*) Source: http://developer.yahoo.com/searchmonkey/smguide/index.html
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SearchMonkey – An example application
• IMDB Infobar• Enhance searches for
imdb.com/name and imdb.com/title
• Adds information about the searched movie and links to the search result
• May be added individually to enhance once search results
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SearchMonkey – How does it work?
• Applications use two types of data services: custom ones and ones provided by Yahoo!
• Yahoo! Data services include:
– Indexed Web Data
– Indexed Semantic Web Data
– Cached 3rd party data feeds
• Custom data services provide additional, individual data
• SearchMonkey application processes the provided data and presents it
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*) Source http://developer.yahoo.com/searchmonkey/smguide/data.html
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SearchMonkey – Ontologies used
• Common vocabularies used: Friend of a Friend( foaf), Dublin Core (dc), VCard(vcard), VCalendar(vcal), etc.
• SearchMonkey specific:– searchmonkey-action.owl: for performing actions as e.g. comparing prices of items– searchmonkey- commerce.owl: for displaying various information collected about
businesses– searchmonkey-feed.owl: for displaying information from a feed– searchmonkey-job.owl: for displaying information found in job descriptions or
recruitment postings– searchmonkey-media.owl: for displaying information about different media types– searchmonkey-product.owl: for displaying information about products or
manufacturers– searchmonkey-resume.owl: for displaying information from a CV
• SearchMonkey does not support reasoning of OWL data
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References
• http://www.w3.org/2001/sw/Europe/reports/chosen_demos_rationale_report/hp-applications-selection.html
• http://dbpedia.org/About• http://watson.kmi.open.ac.uk/Overview.html• http://semanticweb.org/wiki/Main_Page• http://simile.mit.edu/wiki/Piggy_Bank• http://swaml.berlios.de/• http://developer.berlios.de/projects/swaml/• http://rdfs.org/sioc/spec/• http://watson.kmi.open.ac.uk/Overview.html• http://developer.yahoo.com/searchmonkey/
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Next Lecture
# Date Title
1 Introduction
2 Semantic Web Architecture
3 RDF and RDFs
4 Web of hypertext (RDFa, Microformats) and Web of data
5 Semantic Annotations
6 Repositories and SPARQL
7 OWL
8 RIF
9 Web-scale reasoning
10 Social Semantic Web
11 Ontologies and the Semantic Web
12 SWS
13 Tools
14 Applications
15 Exam
www.sti-innsbruck.at © Copyright 2008 STI INNSBRUCK www.sti-innsbruck.at
Questions?
Lecture XIV Dieter Fensel