Linked Open Data and Applications
-
Upload
victor-de-boer -
Category
Education
-
view
258 -
download
6
description
Transcript of Linked Open Data and Applications
Linked Open Data and Applications
Victor de BoerIntelligent Web Applications
24/2/2014
With slides from Rinke Hoekstra
Victor de BoerAssistant professor at VU University Amsterdam
Domain-driven Semantic Technologies, Linked Data
Cultural HeritageDigital History
Linked Data for Development
Today
• What is LOD?– What’s in it for me (the developer)?
• What can I do with LOD– Examples
• My LOD projects and applications
• Pointers, examples, inspiration
What is Linked Open Data?
Open Datais about licenses to allow reuse
Linked Datais about technology for interoperability
★ Available on the web (whatever format), but with an open license
★★Available as machine-readable structured data (e.g. excel instead of image scan of a table)
★★★ as (2) plus non-proprietary format (e.g. CSV instead of excel)
★★★★
All the above plus, Use open standards from W3C (RDF and SPARQL) to identify things, so that people can point at your stuff
★★★★★All the above, plus: Link your data to other people’s data to provide context
www.w3.org/designissues/linkeddata.html
Linked Data five star system
“Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. http://lod-cloud.net/”
Where can I get it?• http://datahub.io/• http://datadryad.org/• https://easy.dans.knaw.nl• http://datacatalogs.org/• http://www.openstreetmap.org/• http://www.w3.org/wiki/DataSetRDFDumps• http://www.freebase.com/• https://data.overheid.nl/• http://data.gov.uk/• http://www.data.gov/• http://publicdata.eu/• http://doc.metalex.eu
• http://linkeddata.few.vu.nl/ Rinke Hoekstra
What can I do with it?
Web of Documents (WWW)Linked Documents
Web of DataLinked Data
Slide stolen from Christophe Gueret
Without…
Slide stolen from Christophe Gueret
With Linked Data
So how do I do it?
Three main ways of accessing remote Linked Data
1. Through HTTP request on the resource URI
2. Through SPARQL queries
3. Get a copy of a dataset
(Linked Data Platform, Linked Data API)
1. Through HTTP request on the resource URI
• HTTP GET on resource, parse, follow links– Simple HTTP requests and RDF parsing– One request per resource: may require many
requests
• Local caching can be done• Crawling
2. Through SPARQL queries
• Full-blown query language
• Needs SPARQL endpoint
$query = "SELECT distinct ?title ?description WHERE {?x <http://data.open.ac.uk/podcast/ontology/relatesToCourse> <http://data.open.ac.uk/course/t209>.?x <http://purl.org/dc/terms/title> ?title.?x <http://www.w3.org/TR/2010/WD-mediaont-10-20100608/description> ?description } LIMIT 10";
$requestURL = 'http://data.open.ac.uk/query?query='.urlencode($query);$response = request($requestURL);
SPARQL in PHP example http://www.greenhughes.com/content/approach-consuming-linked-data-php
3. Get a local copy of a dataset
• through SPARQL CONSTRUCT,• crawling or• direct file download
• Save in triple store – or convert to something else
RDF Libraries
Redland: http://www.librdf.org/ Perl, Python, PHP, Ruby, C#, Objective-C
Jena: http://jena.sourceforge.net/ Java
RDFLib: http://www.rdflib.net/ Python
ARC2: http://arc2.semsol.net/ PHP
ActiveRDF: http://www.activerdf.org/ Ruby
What can I do with it?
Examples: Linked Data BrowsersAllow you to browse remote linked data, clicking
through linked resources and visualising images etc.
TimBL's Tabulatorhttp://dig.csail.mit.edu/2005/ajar/ajaw/tab.html
DiscoMarblesOpenLink data browser
Explore more!• http://sig.ma• http://mspace.fm/• http://www.google.com/publicdata• http://datamarket.com/• http://www.wolframalpha.com/
OpenPhacts explorer
http://www.openphacts.org/
Fancy mashups
www.bbc.co.uk/music
Intelligent Web Apps!
• http://mashupbreakdown.com/• http://conflicthistory.com/• http://traintimes.org.uk/map/tube/• http://bikes.oobrien.com/• http://www.nomenest.info/• http://www.sandbag.org.uk/maps/offsetmap/• http://www.sandbag.org.uk/maps/emissionsmap/
• http://www.data-art.net/locus/
• http://wheredoesmymoneygo.org/• http://openspending.org/• http://energy.publicdata.eu/• http://www.fearsquare.com• http://energielabelapp.nl/• http://register.ocistimo.si/• http://epdb.eu/eulegislation/• http://www.travelschecklist.com/
Rinke Hoekstra
Enough about me, let’s talk about me.
Multimedia E-culture Demonstrator
MultimediaN E-Culture project
• Museums have increasingly nice websites • But: most of them are driven by stand-alone collection
databases
• Data is isolated, both syntactically and semantically
• If users can do cross-collection search, the individual collections become more valuable!
• Semantic Search
MultimediaN E-Culture
2003-2008: UvA, VU, CWI, DEN, ICN
“Use Semantic Web techniques to facilitate interoperability between cultural heritage institutes”
29
Semantic search
30
• Search for via annotations with concepts (semantic links)
• Use the type of semantic link to provide meaningful presentation of the search results
Paris
Montmartre
PartOf
Query“Paris”
vocabulary alignment
31
“Tokugawa”
SVCN period Edo
SVCN is local in-house ethnology thesaurus
AAT style/period Edo (Japanese period) Tokugawa
AAT is Getty’s Art & Architecture Thesaurus
Search, Show and Annotate
32
Multiple search/browse/result interfacesGoogle-likeLocal viewMapGraph displayFacet browser
Split up data based on attribute-valuesMultiple criteria
Annotation InterfaceUse of semantic autocompletionExperts Laypeople?
Verrijkt Koninkrijk
History of German occupied Dutch society (1940-1945)
Published between 1969 and 1991 in 14 volumes, 30 parts, 18.000 pages
1. Digitization, 2. Open Data, 3. Enriched access with Linked Open Data
Het Koninkrijk der Nederlanden in de Tweede Wereldoorlog
country, collection, doc-type, volume, chapter, section, sub-section, paragraph
SKOS vocabularies as stepping stones
Back-of-the-book index (SKOS)
15.234 Concepts121.525 references
Named Entities (SKOS)
88.249 Concepts364,924 references
niod:Blitzkrieg
niod:oai_wo2_niod_nl_rec_102045 dct:subjec
t
http://resolver.verrijktkoninkrijk.nl/nl.vk.d.reg.4.1386
botb:Blitzkrieg
skos:exactMatch
skos:exactMatch
skos:exactMatch
http://semanticweb.cs.vu.nl/verrijktkoninkrijk/
http://purl.org/collections/nl/niod/V-wapens.rdfDereferenceable URIs!
SELECT * WHERE{ ?s skos:prefLabel ?pl.?s skos:closeMatch ?geo.?geo gn:parentADM1 ?prov.?prov gn:name ?provname.?s niod:pageRef ?pref. }
0
2000
4000
6000
8000
10000
12000NE indexBotB index
Geographical analysis using background knowledge from
GeoNames
SPARQL for Rhttp://linkedscience.org/tools/sparql-package-for-r/
Results are links to paragraphs
National-Socialist29%
Social-Democrat21%
Protestant13%
Liberal12%
R-Catholic12%
Com
munist8%
Jewish5%
Pillar1 Pillar2 CoLiber. Protestant 0.29Protestant R-Cath. 0.22Liber. R-Cath. 0.21Comm Soc-dem 0.20Liber. Soc-dem 0.15
Quick analysis, inspiring researchers
Hackathon
Dutch Ships and Sailors
Dutch Ships and Sailors
VOC Opvarenden
Dutch Asiatic Shipping
Generale Zeemonsterrollen
Noordelijke Monsterrollen
KB Newspapers
gz:Mercuur
1782
gz:Buijksloot
gz:Batavia
gz:Claas Roem
voc:Claas Roem
voc:Buijksloot
1752das:Mercuur
das:Departure
das:Roem, Klaas
19-12-1780 das:Texel
das:Arrival
20-7-1781 das:Batavia
das:Voyage1
Web of Data
Example web application?
VOC Opvarenden
Dutch Asiatic Shipping
Generale Zeemonsterrollen
Noordelijke Monsterrollen
KB Newspapers
http://semanticweb.cs.vu.nl/dsshttp://dutchshipsandsailors.nl/
Linked Data 4 DevelopmentDevelopment
Linked Data for International Aid Transparency Initiative
Msc. Thesis by Kasper Brandt Victor de Boer
Introduction - IATI
“IATI is a voluntary, multi-stakeholder initiative that seeks to improve the transparency of aid in order to increase its effectiveness in tackling poverty.”
-- http://www.aidtransparency.net/
IATI datamodelActivities Organisations
Aid TypeCountryCurrencyGeographical precisionLanguageLocation typeOrganisation rolePolicy markerRegionSectorTransaction type
Vocabularies
Model and links based on requirements elicitated from experts
Iterative Requirements Engineering Process Model by Loucopoulos and Karakostas
Linking datasets and Applications User questions
1. In total, how much does a given country receive in aid?
2. A comparative index of aid versus the Human Development Index.
3. What is the geographic location of a project? How much aid went to a given province, constituency or village?o Is the aid spent in places where the need is
highest? Is it well distributed across the country?
o Can we attribute sub-national breakdowns for aid so we can see how much goes to different parts of recipient countries?
4. How does violent conflict in recipient countries affect aid activities?
5. How does aid spending as registered in the IATI standard compare to World Bank indicators?
IATI 2 LOD application
http://iati2lod.appspot.com/applications
http://iati2lod.appspot.com/1. In total, how much does a given country receive in aid?
2. A comparative index of aid versus the Human Development Index.
http://iati2lod.appspot.com/
http://iati2lod.appspot.com/4. How does violent conflict in recipient countries affect aid activities?5. How does aid spending as registered in the IATI standard compare to World
Bank indicators?
Talking to Linked Data
Local market data
Communiqué
GSM/Voice interface
Web Interface Text-To-Speech
Community radio
RadioMarché
Sahel Eco operativeBuyers
EcoMash
[M.Sc. thesis by Henk Kroon]
Linked Data for Development (LD4D)
Web applications
<VoiceXML> to SPARQL*
Voice browserTel: +31208080855
Skype: +990009369996162208
RadioMarché Linked market data
‘Allo, Linked Data?
DBpediaGeoNames
Agrovoc
Linked Open Data…
…should make it easier for developers to develop IWAs
… from distributed datasources
… with heterogeneous data
Go build stuff!
Links to datasets and applications
• http://semanticweb.cs.vu.nl/verrijktkoninkrijk• http://semanticweb.cs.vu.nl/dss• http://semanticweb.cs.vu.nl/radiomarche• http://semanticweb.cs.vu.nl/iati• http://eculture.multimedian.nl/demo
• http://iati2lod.appspot.com/• http://eculture.multimedian.nl
• http://Worldwidesemanticweb.org
/sparql/query=/user/query/yasgui/index.html