Amsterdam Museum as

Five-star Linked Data

Judith van Gent Victor de Boer

Collection Amsterdam Museum– More than 75.000 objects

paintings, drawings, prints, coins, statues, photos, glass, silver, furniture, ceramics, books, historic interiors, costumes, textiles, clocks, shoes, etc.

– Around 20% on show, rest in storage depots

Collection Amsterdam Museum– of the Amsterdam people– of international importance– sharing data/knowledge is policy

2010 AM entire collection online• digital depot • CC BY-SA• not all data optimal • public can react/contribute

collectie.ahm.nl

AM open data– Use and reuse!– Adlib database open

– Adlib API (XML output)– OAI-PMH (XML, Dublin Core)– Linked Open Data (VU EDM)

– Metadata / images– Spectrum, Dublin Core, Texts

– Persistent id i.o.– id.amsterdammuseum.nl/collection/123

• OAI protocol– Digitalecollectie.nl > Europeana– ED*IT– Oneindig NH

• Wikipedia• Adlib API

– iPhone app– Apps for Amsterdam

“Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. http://lod-cloud.net/”

Linked Data

Why linked data (1/2)

Slide stolen from Christophe Gueret

Why linked data (2/2)

Slide stolen from Christophe Gueret

Europeana• “Europeana enables people to explore the digital

resources of Europe's museums, libraries, archives and audio-visual collections.’’

www.europeana.eu

From portal… …to data aggregator.

AM metadata• Adlib database XML API

• Object metadata • 73.000 objects, 256MB • Nested XML

• Concept Thesaurus• 27.000, 9MB• Different types (geo,motif, event)

• Person ‘Thesaurus’• 67.000 persons, 10MB• Consolidated from object metadata fields• Creators, annotators, reproduction

creators, institutions,

<record priref="10541“ > <acquisition.date>1997</acquisition.date> <dimension> <dimension.type>hoogte</dimension.type> <dimension.unit>cm</dimension.unit> <dimension.value>6</dimension.value> </dimension> …</record>

<record priref="28024“ > <term>Kalverstraat 124</term> <broader_term>Kalverstraat</broader_term> <term.type>GEOKEYW </term.type> </record>

<record priref="6" > <biography>boekverkoper en uitgever van cartografie</biography> <birth.date.start>1659</birth.date.start> <death.date.start>1733</death.date.start> <name>Aa, Pieter van der</name> <nationality>Nederlands</nationality> <use>Aa, Pieter van der (I)</use> </record>

Four rules of 5-star Linked Data

1. Use URIs as names for things

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

3. When someone looks up a URI, provide useful information, using the standards (RDF*, SPARQL)

4. Include links to other URIs. so that they can discover more things.

http://www.w3.org/DesignIssues/LinkedData.html

Amsterdam Museum URIs• PURL basename: http://purl.org/collections/nl/am/

• Objects: Use “prirefs”, prefixed by “proxy-”– http://purl.org/collections/nl/am/proxy-63432

• Concepts & Persons: Use “prirefs”, prefixed by “p-”, or “t-” – http://purl.org/collections/nl/am/p-201

• Properties (schema): Use XML element name – http://purl.org/collections/nl/am/acquisition.date

PS: am:p-1234 is a shorthand for http://

purl.org/collections/nl/am/p-1234

Four rules of 5-star Linked Data

1. Use URIs as names for things

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

3. When someone looks up a URI, provide useful information, using the standards (RDF*, SPARQL)

4. Include links to other URIs. so that they can discover more things.

http://www.w3.org/DesignIssues/LinkedData.html

XMLRDF

• Modular setup 1. Start with XML (OAI-harvest)2. Syntactic transformation to RDF3. Rewrite raw RDF using simple rules4. Define mapping schema to EDM/other

RDF conversion (XMLRDF)<record priref="19319 “ > <date>1651</date> <maker>Rembrandt (1606-1669)</maker> <object.type>etsplaat</object.type> …</record>

am:Record_:bn1

“19319 ”

“1651”

priref

date

am:Personam:p-1234

skos:Conceptam:etsplaat

“1234”

“1606”

am:prirefam:birthdate

“etsplaat”

maker

object.type

“Rembrandt (1606-1669)”

“etsplaat”

am:Recordam:proxy-19319

“19319 ”

“1651”am:priref

am:date

am:maker

am:object.type

“Rembrandt”rda:name

skos:prefLabel

Mapping schema

am:proxy_22093

1770

1790

am:productiondateStart

am:productiondateEnd

rdfs:subPropertyOf

dcterms:created

Cliopatria

RDF(s) storage

HTTP server

SPARQL

Prolog

Web interface

SPARQL-app Browser

Logic

Purl.org redirect

http://semanticweb.cs.vu.nl/

6.000.000 RDF triples

text/html

<?xml version='1.0' encoding='UTF-8'?> <!DOCTYPE rdf:RDF [ <!ENTITY am 'http://purl.org/collections/nl/am/'> <!ENTITY rdf 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'> <!ENTITY skos 'http://www.w3.org/2004/02/skos/core#'> ]>

<rdf:RDF xmlns:am="&am;" xmlns:rdf="&rdf;" xmlns:skos="&skos;" > <skos:ConceptScheme rdf:about="&am;AM_ConceptScheme"/> <skos:Concept rdf:about="&am;t-1" am:priref="1"> <am:termType rdf:resource="&am;t-termtypeGEOKEYW"/> <am:termType rdf:resource="&am;t-termtypePLACE"/> <skos:broader rdf:resource="&am;t-2688"/> <skos:inScheme rdf:resource="&am;AM_ConceptScheme"/> <skos:prefLabel xml:lang="nl">Wassenaar</skos:prefLabel> </skos:Concept>

<skos:Concept rdf:about="&am;t-10" am:priref="10"> <am:termType rdf:resource="&am;t-termtypeGEOKEYW"/> <am:termType rdf:resource="&am;t-termtypePLACE"/> <skos:broader rdf:resource="&am;t-12"/> <skos:inScheme rdf:resource="&am;AM_ConceptScheme"/> <skos:prefLabel xml:lang="nl">Driebergen</skos:prefLabel> </skos:Concept>

<skos:Concept rdf:about="&am;t-100" am:priref="100"> <am:termType rdf:resource="&am;t-termtypeGEOKEYW"/> <am:termType rdf:resource="&am;t-termtypePLACE"/> <skos:broader rdf:resource="&am;t-12"/> <skos:inScheme rdf:resource="&am;AM_ConceptScheme"/> <skos:narrower rdf:resource="&am;t-31297"/> <skos:prefLabel xml:lang="nl">Naarden</skos:prefLabel> </skos:Concept> <skos:Concept rdf:about="&am;t-1000" am:priref="1000"> <am:termType rdf:resource="&am;t-termtypePLACE"/> <skos:inScheme rdf:resource="&am;AM_ConceptScheme"/> <skos:prefLabel xml:lang="nl">Clos-Lucé</skos:prefLabel> </skos:Concept>

application/rdf+xml

http://semanticweb.cs.vu.nl/europeana/user/query

SPARQL

Again, the rules of Linked Data

1. Use URIs as names for things 2. Use HTTP URIs so that people can look up

those names. 3. When someone looks up a URI, provide

useful information, using the standards (RDF*, SPARQL)

4. Include links to other URIs. so that they can discover more things.

http://www.w3.org/DesignIssues/LinkedData.html

Link to other sources

am:Personam:p-1234

“1234”

“1606”

am:prirefam:birthdateam:Record

am:proxy-19319

“19319 ”

“1651”am:priref

am:date

am:maker

“Rembrandt”rda:name

Viaf:PersonViaf:RebrandtvanRijn

“Dutch”Viaf:nationality

rdfs:label

“Rembrandt Harmensz. Van Rijn”

owl:sameAs (?)

Amalgame alignment platform

• Semi-automatic linking– Simple automatic techniques, – chained together by hand

• 3500+ links put in RDF– 143 places linked to

GeoNames– 1076 persons linked to ULAN

(VIAF)– 34 persons linked to DBPedia– 2498 concepts AATNed.

CKAN Data Hub

http://thedatahub.org/dataset/amsterdam-museum-as-edm-lod

And now applications!…right??

Plaatsen van BetekenisLocal Linked Data (Amsterdam)

endv.de.boer@vu.nl

j.vangent@amsterdammuseum.nl

amsterdammuseum.nlhttp://collectie.ahm.nl/

http://amdata.adlibsoft.com/wwwopac.ashx

http://semanticweb.cs.vu.nl/lod/am/

EDM

What kind of RDF?

• Europeana Data Model (EDM)– Keep original metadata intact– Use sem web (LD) principles: RDF

• Re-use of standard models– Dublin Core for metadata representation

• creator, date, title etc.

– SKOS for vocabularies• preferredLabel, hasBroader, etc.

– OAI-ORE to allow for aggregations etc.

EDM voorbeeld

proxyobject

metadataAggregation

Provenance +web

views/plaatjes

Physical Objectgeen

metadata