Some of the exercises we did during a week-long class on "Publishing and Using Linked Open Data" at the University of Maryland Digital Humanities Winter Institute.

1. Digital Humanities Winter Institute
Publishing and Using Linked Open Data
January 7-11, 2013
http://mith.umd.edu/dhwiwiki/index.php/DHWI_Wiki:Publishing_and_Using_Linked_Open_Data
Syllabus with readings: http://lod4h.pbworks.com/w/page/58948790/DHWI_Syllabus
What I Did
Kindly note: This is all just practice and play. None of this is real.
Georgina Goodlander
@bathlander

2. Brought some sample museum data

3. Cleaned it up in Open Refine, assigned URIs
Split display names into first and last names, cleaned up dates, converted fractions to decimals,
split dimensions into separate columns then put them back together again, trimmed white
spaces.
GERL to combine columns for dimensions (very impressed that I wrote this):
if(isBlank(cells["Dimensions"].value), "0", cells["Dimensions"].value) + " x " +
if(isBlank(cells["Width in inches"].value), "0", cells["Width in inches"].value) + " x " +
if(isBlank(cells["Depth in inches"].value), "0", cells["Depth in inches"].value)

4. Assigned properties (foaf, dcterms, dc)

5. Exported as RDF/XML
<?xml version="1.0" encoding="UTF-8"?>
<rdf:RDF
xmlns:dc="http://purl.org/dc/elements/1.1/"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xmlns:foaf="http://xmlns.com/foaf/0.1/"
xmlns:owl="http://www.w3.org/2002/07/owl#"
xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:dcterms="http://purl.org/dc/terms/">
<rdf:Description rdf:about="http://americanart.si.edu/objects2011.25.2">
<foaf:name>Felrath Hines</foaf:name>
<foaf:givenName>Felrath</foaf:givenName>
<foaf:familyName>Hines</foaf:familyName>
<dcterms:identifier>2011.25.2</dcterms:identifier>
<dcterms:title>Abstract Landscape</dcterms:title>
<dcterms:medium>oil on linen</dcterms:medium>
<dc:date>1964</dc:date>
<dcterms:rights>Gift of Dorothy C. Fisher, wife of the artist</dcterms:rights>
<dcterms:extent>72 x 72 x 0.875</dcterms:extent>
</rdf:Description>

6. Imported into Sesame
At this point the data is published and link-able, but not yet linked to other data sets. It is also
important to publish under an open license, such as CC0.

7. Ran SPARQL Queries SELECT ?familyName
WHERE
{
?s foaf:familyName ?familyName .
Returns all family names in ascending order }
ORDER BY ASC(?familyName)
SELECT ?title
WHERE
{
Returns all titles for artworks that
?s dcterms:title ?title .
have “oil” in the medium
?s dcterms:medium ?medium .
FILTER (regex (?medium, "oil", "i"))
}
SELECT ?familyName ?objectid ?date
WHERE
{
Returns family names, object IDs, and ?s foaf:familyName ?familyName .
dates for works made after 1950 ?s dcterms:identifier ?objectid .
?s dc:date ?date .
FILTER (?date > "1950") .
}

8. Helpful Resources
Links from the Instructor, Richard Urban:
http://www.diigo.com/user/musebrarian/dhwi_example
Cool URIs: http://www.w3.org/TR/cooluris
RDF validator: http://rdfabout.com/demo/validator/
Semantic web stack: http://en.wikipedia.org/wiki/Semantic_Web_Stack
Protege Ontology Editor: http://protege.stanford.edu
Foaf: http://xmlns.com/foaf/spec/20100809.html
SKOS: www.w3.org/2004/02/skos/vocabs
Dublin Core: http://purl.org/dc/terms/
SPARQL Examples: http://MITH.umd.edu/dhwiwiki/index.php/SPARQL_Examples
More SPARQL: http://www.w3.org/TR/rdf-sparql-query/#tests
Even more SPARQL: http://www.w3.org/2009/Talks/0615-qbe/
SPARQL endpoint for Dbpedia: http://DBPedia.org/snorql
Using GERL functions: http://code.google.com/p/google-
refine/wiki/GRELStringFunctions
Publishing Linked Open Data (table): http://linkeddatabook.com/editions/1.0/#htoc61
Dbpedia ontologies mapping: http://mappings.dbpedia.org/server/ontology/classes/
Creative Commons 0: creativecommons.org/choose/zero
GLAM open data sets: http://datahub.io/group/open-glam