DBpedia - A Crystallization Point

DBpedia - A Crystallization Point

for the Web of Data2011.10.05

Junghee - Han

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Outline

The DBpedia Project Understanding Linked Data The DBpedia Knowledge Extraction Framework The DBpedia Knowledge Base Accessing the DBpedia Knowledge Base Applications facilitated by DBpedia

DBpedia - A Crystallization Point for the Web of Data

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The DBpedia Project

DBpedia 위키피디아로부터 구조화된 정보를 추출하고 , 이를

웹에서 이용할 수 있도록 만들기 위한 커뮤니티

Dbpedia is a community effort to Extract structured information from Wikipedia Make this information available on the Web under an open licenseInterlink the DBpedia dataset with other open datasets on the Web


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DBpedia knowledge base Currently describes more than 2.6 million entities

- 198,000 persons - 328,000 places - 101,000 musical works - 34,000 films - 20,000 companies.

The knowledge base contains 3.1 million links to external web pages and 4.9 million RDF links into other Web data sources.


The DBpedia Project

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Linked Data

참고 :

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Linked Data

참고 :

WebBrowsers

SearchEngines

HTTP HTTP

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Linked Data

RDF stands for

Resource : URI 를 갖는 모든 것 ( 웹페이지 , 이미지 , 동영상등 ) Description : 자원 (Resource) 들의 속성 , 특성 , 관계기술

Framework : 위의 것들을 기술하기 위한 모델 , 언어 , 문법

RDF 는 Graph Model 을 갖고 있다 .

참고 : [KSWC2010] 데이터의 가치를 높이는 Linked Data

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Linked Data Graph Model 예시

RDF Syntax

Triple 형식표현


SPARQL(Simple Protocol and RDF Query Language) W3C 에서 만든 RDF 질의 언어

Linked Data

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1. Use URI(Uniform Resource Identifier)s as names for things2. Use HTTP URIs so that people can look up those names3. When someone looks up a URI, provide useful RDF Information4. Include RDF statements that link to other URIs so that they

can discover related things

Tim Berners-Lee 2007 http://www.w3.org/DesignIssues/LinkedData.html


Linked Data

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http://bibleontology.com/page/Bilhah

1. Use URIs as names for things



Linked Data

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2. Use HTTP URIs so that people can look up those names



Linked Data

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3. When someone looks up a URI, provide useful RDF Information


Linked Data

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http:// http://bibleontology.com/page/Bilhah

4. Include RDF statements that link to other URIs so that they can discover related things

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HongGilDong

Hong, Gil Dong 35

Seoul

SemanticWeb

[hasPhotoCollection]

http://dbpedia.org/resource/Semantic_Web

http://www4.wiwiss.fu-berlin.de/flickrwrappr/photos/Semantic_Web

[sameAs]

http://dbpedia.org/resource/Seoul

http://sws.geonames.org/1835848/

http://sws.geonames.org/1835848/nearby.rdf

[nearbyFeatures]

[residences]

[researches]

[name] [age]

Linked Data


http://www.flickr.com/

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SPARQL

Linked Data


SQL

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공간정보

여행정보

교통정보

부동산정보문화재정

보

문헌정보토지정보

환경정보

XXX 정보

상품정보

일자리정보

단절된 국가 공공정보

공간정보

여행정보

교통정보

부동산정보문화재정

보

문헌정보토지정보

환경정보

XXX 정보

상품정보

일자리정보

연결된 국가 공공정보

포털 및 언론 대학 기타

민간 정보

DBPedia BBC etc해외 정보

여행정보 공간정보 문헌정보 환경정보 XXX 정보국가 공공정보

Linked Data


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Wikipedia Content

Title

Description

Languages

Web Links

Categorization

Domain specificData

Images

Infoboxes


Until March 2010, the DBpedia project was using a PHP-based extraction framework to extract different kinds of structured information from Wikipedia. This framework has been superseded by the new Scala-based extraction framework and the old PHP framework is not maintained anymore

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The DBpedia Knowledge Extraction Framework(1/2)

Labels(title,rdfs:label)Abstracts(first paragraph,rdfs:comment)Interlanguage links. Images. Redirects. Disambiguation(depedia:disambiguates) External links(dbpedia:reference)Page links(dbpedia:wikilink)Homepages(foaf:homepage)Geo-coordinates. Person data. PND. SKOS categories. Page ID. Revision ID. Category label. Article categories. Mappings. Infobox.

Currently 19 extractors


http://wiki.dbpedia.org/Documentation

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The DBpedia Knowledge Extraction Framework(2/2)

Two Work-Flows Dump-based extraction

-The Wikimedia Foundation publishes SQL dumps of all Wikipedia editions on a monthly basis-The dump-based workflow uses the DatabaseWikipedia page collection as the source of article texts and the N-Triples serializer as the output destination.

Live extraction

Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH)


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Infobox Extraction

dbpedia:BBC p:network_name„British Broadcasting Corporation (BBC)“

dbpedia:BBC p:country dbpedia:United_Kingdom

dbpedia:BBC p:key_people dbpedia:Michael_Lyons dbpedia:Mark_Thompson


The DBpedia Knowledge Base

Identifying EntitiesResources are assigned a URI according to the pattern http://dbpedia.org/resource/Name (where Name is taken from the URL of the source Wikipedia article, which has the form http://en.wikipedia.org/wiki/Name)

Classifying EntitiesDBpedia entities are classified within four classification schemata in order to fulfill different application requirements.

- Wikipedia Categories - YAGO - UMBEL(Upper Mapping and Binding Exchange Layer) - DBpedia Ontology Describing Entities

Every DBpedia entity is described by a set of general properties

21DBpedia - A Crystallization Point for the Web of Data

Accessing the DBpedia Knowledge Base over the Web

Linked Data DBpedia resource identifiers(ex: http://dbpedia.org/resource/Berlin) SPARQL Endpoint

http://dbpedia.org/sparql

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RDF Dumps http://wiki.dbpedia.org/Downloads32

Lookup Index http://lookup.dbpedia.org/api/search.asmx


Interlinked Web Content


Currently contains 4.9 million outgoing RDF links

Applications facilitated by Dbpedia(1/3)

Browsing and Exploration DBpedia Mobile



Querying and Search DBpedia Query Builder

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http://querybuilder.dbpedia.orgDBpedia - A Crystallization Point for the Web of Data


Querying and Search Relationship Finder

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ConclusionThe resulting DBpedia knowledge base covers a wide range of different domains and connects entities across these domains.


Future WorkCross-language infobox knowledge fusion

- Derive an astonishingly detailed multi-domain knowledge baseWikipedia article augmentation

- Develop a MediaWiki extension that augments Wikipedia articles with additional information as well as media items (pictures, audio) from these sourcesWikipedia consistency checking

- Improve the overall quality of Wikipedia

Conclusions and Future Work

Documents

DBpedia - A Crystallization Point