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

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“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

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Multiple search/browse/result interfacesGoogle-likeLocal viewMapGraph displayFacet browser

Split up data based on attribute-valuesMultiple criteria

Annotation InterfaceUse of semantic autocompletionExperts Laypeople?

http://e-culture.multimedian.nl/demo/session/search

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