Semantic Web Technologies: Principles and Practices

Steffen Staab Semantic (Web) Technologies – Principles and Practice 1Institute for Web Science and Technologies · University of Koblenz-Landau, GermanyWeb and Internet Science Group · ECS · University of Southampton, UK &

Semantic (Web) Technologies

Principles and Practices

Steffen Staab

Steffen Staab Semantic (Web) Technologies – Principles and Practice 2

Daten – Menschen

Meaning?


Traditional Information System

Business Logics

Structured DataUnstructured

Data

Presentation and Interaction

Characteristics:• Processes are

known• Data structures

are known• Meaning of data

primarily in schema and code


Today‘s Information Eco-systems

Examples:• Open Data• 10000 DBs/firm• Cloud(s)• Ad-hoc data

Characteristics:• Little structure• Semi-structured

data• Meaning of data of

primary importance!


Principles


Issue 1: Data ModelsData Models:• Relational• Tree (XML,...)• Document oriented• Stream• Array• Graph-DB

RDFGraph data model as common denominator


Dealing with issue 1: RDF as data model

RDFGraph data model as common denominator

knowsStaab Saric

56075

hasPLZ


Issue 2: Conceptual Models

Conceptual Models:• ER• UML• ...

RDFSOntology as common

denominator


Issue 2: RDFS as common conceptual meta model

RDFSfor explicit conceptual

description

knowsStaab Saric

56075

hasPLZ

Academic Industr.employee

typetype


Issue 3: System boundaries

IRIsfor globally unique

referencing

o:knowsko:Staab bi:Saric

56075

o:hasPLZ

o:Academic o:Industr.employee

rdf:typerdf:type

o = http://myonto.orgrdf = https://www.w3.org/2001/sw/


Information Systems

Traditional:• Closed world• Known processes• Carefully curated data• Data storage

expensive and limited

Data = Truth

Novel:• Open world• Ad-hoc processes• Error-prone data• Data storage cheap

and almost unlimited

Data = Signal

Reality in companies: Both! Not a contradiction!


Practices

Knowledge Graphs• Google• Hewlett-Packard• Microsoft• Samsung• Reuters

Open Knowledge Graphs• DBPedia• Wikidata• Yago

Rich Semantic Infrastructures• BBC• New York Times• Elsevier• British Museum

Semantic Thesauri• UN FAO• Deutsche Nationalbibliothek• Roche• ...


Practices 1: Data=Signal


Principles

http://de.slideshare.net/laroyo/lecture-6-32380702


Principles



Principles



Principles



Principles



Practices 2: Data = Truth


Information Architecture Elsevier Examples

All following slides covering Elsevier Example are courtesy by Paul Groth


INFORMATION ARCHITECTURE DEFINITIONS

• The combination of organization, labeling, and navigation schemes within an information system.

• The structural design of an information space to facilitate task completion and intuitive access to content.

• The art and science of structuring and classifying web sites and intranets to help people find and manage information.

• An emerging discipline and community of practice focusing on bringing principles of design and architecture to the digital landscape. Dillon, A. and Turnbull, D. (2006) Information

Architecture, Encyclopedia of Library and Information Science, Marcel-Dekker.


FOUR TASKS IN INFORMATION ARCHITECTURE

1. Creating Content Organization Systems

2. Creating Semantic Organization Systems

3. Creating Navigation Systems

4. Creating Interaction Designs


Lots of sources at Elsevier



Documents by subject area


ORGANIZING INFORMATION (TAXONOMIES)



CREATING NAVIGATION SYSTEMS


MOBILE REDESIGN



GLOBAL DIGITAL OBJECT IDENTIFIERS (DOI)


ORCID: GLOBAL IDENTIFIERS FOR PEOPLE


ARCHIVES





Linking BBC data

Matthew Woodhttp://de.slideshare.net/fantasticlife/semweb-at-the-bbc

Oliver Bartletthttp://www.bbc.co.uk/blogs/internet/entries/af6b613e-6935-3165-

93ca-9319e1887858


bbc.co.uk was incoherent…


Saturday Kitchen Episode Page Saturday Kitchen Recipe

About 10 years ago


Unless we link our data…• global visual language• common navigation patterns• technology refresh• page assembly layers• “common platforms”

…are all treating the symptoms, not the illness


ProgrammesMusic

Topics

Users

Events

News Food

Gardening

The BBC from 10,000 feet


What BBC has done:• Moved to MusicBrainz as music metadata supplier• Designed and built /programmes according to linked

data principles• Published the Programmes Ontology• Used the Music Ontology to publish RDF for /music• Experimented with pushing programme ontology

data over XMPP





What else?• RDF on /programmes• RDFa on /programmes and /music• Wikipedia/Dbpedia for topic aggregations on

/programmes• Using MusicBrainz <> Dbpedia linked data

equivalency to aggregate artist information at /music• /events as linked data


Practices 3: Data = Truth + Signal


Google for „Vincent van Gogh“

Screenshot by Kingsley Idehen


Van Gogh on Facebook


Facebook Data Object



Van Gogh on Wikipedia


DBPedia Data Object

Note: DBPedia harvests knowledge from Wikipedia



Freebase Data Object

Note: MetaWeb producing Freebase is a Semantic Web company bought by Google in 2010; Freebase is now donated to WikiData



Google Search with Google Knowledge Graph


Google knowledge graph API

1st API: Search2nd API: Knowledge Graph

....among thousands of APIs used in Google!

https://developers.google.com/knowledge-graph/

Schema.org typesJSON-LD Syntax

Usage: e.g. named entity spotting


Yet another challenge / opportunity:Open Practices


Semantics at Scale: Linked Open Data Cloud

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

Explicit meaning: Re-used ontologies

Implicit meaning:Linking of data

Meaning through social contexts


ProgrammesMusic

Topics

Users

Events

News Food

Gardening


Semantics at Scale: Linked Open Data Cloud

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

Explicit meaning: Re-used ontologies

Implicit meaning:Linking of data

Meaning through social contexts

Why should a for-profit (pharmaceutical) company think about opening data?• Not all data is competitive advantage, but all data implies costs• Sharing of – some (!) – data is inevitable


• Semantic Web Technologies – Simple ideas– Infrastructures supported by key players– More technologies to talk about:

• SPARQL, RDF-A, Schema.org, SKOS, PROVO, R2RML...

• Tim Berners-Lee:„Linked Data is 'the web done right.‘“http://www.zdnet.com/article/tim-berners-lee-talks-cranberry-sauce-and-linked-data-in-new-york-city/

• Watch 10 Minutes: https://www.youtube.com/watch?v=ga1aSJXCFe0

Conclusion

http://www.zdnet.com/article/tim-berners-lee-talks-cranberry-sauce-and-linked-data-in-new-york-city/

http://www.zdnet.com/article/tim-berners-lee-talks-cranberry-sauce-and-linked-data-in-new-york-city/

Steffen Staab Semantic (Web) Technologies – Principles and Practice 64Institute for Web Science and Technologies · University of Koblenz-Landau, GermanyWeb and Internet Science Group · ECS · University of Southampton, UK &

Thank you for your attention!

Semantic Web Technologies: Principles and Practices

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