methodological guidelines for publishing linked...

Methodological Guidelines for Publishing

Linked Data

Boris Villazón-Terrazas bvillazon@isoco.com

@boricles Slides available at: http://www.slideshare.net/boricles/

Acknowledgements: OEG

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Main References

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Wood, David (Ed) Linking Government Data - 2011!

Methodological Guidelines for Publishing Government Linked Data!

Boris Villazón-Terrazas, Luis M. Vilches, Oscar Corcho, Asunción Gómez-Pérez!

Best Practices for Publishing Linked Data!

W3C Editor’s Draft – Government Linked Data Working Group!

Bernadette Hyland, Boris Villazón-Terrazas, Ghislain Atemezing!

https://dvcs.w3.org/hg/gld/raw-file/default/bp/index.html!

Cookbook for Open Government Linked Data!

W3C Editor’s Draft – Government Linked Data Working Group!

Bernadette Hyland, Boris Villazón-Terrazas!

http://www.w3.org/2011/gld/wiki/Linked_Data_Cookbook!

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ToC »  Introduction

» Guidelines for Publishing Linked Data

» Uses Cases

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Publishing Linked Data

?

Process that involves a high number of steps, design decisions and technologies.

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Iterative and Incremental Linked Data Life Cycle

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Iterative and Incremental Linked Data Life Cycle

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Specification

§  Identification and analysis of the data sources

§  URI design

§  Definition of the license

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Specification Identification and analysis of the data sources

After we have identified and selected the government data sources

§  Search and compile all the available data and

documentation about those resources

§  Identify the schema of those resources including conceptual components and their relationships

§  Identify the items in the domain, i.e., things whose properties and relations are described in the data sources

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Specification URI Design

§  Use meaningful URIs, instead of opaque URIs, when possible

§  Separate TBox (ontology model) from ABox (instances) URIs.

-  Base URI http://data.gov.bo/ http://health.data.gov.bo/

-  TBox URIs http://data.gov.bo/ontology/{class|property}

-  ABox URIs http://data.gov.bo/resource/ http://data.gov.bo/resource/province/Tiraque

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Iterative and Incremental Linked Data Life Cycle

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Modelling Reuse available vocabularies

Search for suitable vocabularies

Linked Open Vocabularies

are there suitable

vocabularies?

Build the vocabulary by reusing available

vocabularies

Yes

No

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Modelling Reuse available non-ontological resources

Search for suitable non-ontological resources

Highly reliable Web Sites

Domain-related sites

Government Catalogs

are there suitable

resources?

Build the vocabulary by transforming available

resources

Yes

No

Build the vocabulary from scratch

Boris Villazón-Terrazas, A Method for Reusing and Re-Engineering Non-Ontological Resources for Building Ontologies. IOS Press 2012

*

…

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Iterative and Incremental Linked Data Life Cycle

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Generation

§  Transformation

§  Data cleansing / curation

§  Linking

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Generation Transformation

§  Take the data sources selected in the specification activity and transform them to RDF according to the vocabulary created in the modelling activity

§  Some tools -  CSV and spreadsheets

•  RDF extension of Google Refine, XLWrap, RDF123, NOR2O

-  RDB •  D2R Server, ODEMapster, W3C RDB2RDF WG – R2RML

-  XML •  GRDDL, ReDeFer

http://www.w3.org/wiki/ConverterToRdf

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Generation Transformation – RDB2RDF

§  A majority of dynamic Web content is backed by relational databases (RDB), and so are many enterprise systems.

§  W3C RDB2RDF Working Group R2RML: RDB to RDF Mapping Language - http://www.w3.org/TR/r2rml/ Direct Mapping - http://www.w3.org/TR/rdb-direct-mapping/ R2RML and Direct Mapping Test Cases - http://www.w3.org/2001/sw/rdb2rdf/test-cases/ RDB2RDF Implementation Report - http://www.w3.org/TR/rdb2rdf-test-cases/

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transformation description

transformation engine

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Generation Transformation – Spreadsheets to RDF

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Industry Production Index

Province

Year

NOR2O  

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Generation

§  Tool for generating RDF from geospatial information

§  The geometry could be available in GML or WKT

https://github.com/boricles/geometry2rdf

Transformation – Geospatial to RDF

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Generation Transformation – MARC21 to RDF

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§  A MARC Mappings and RDF generator

MARiMbA  

Classification

Annotation

Mapping templates

Relationships

MARiMbA  

Domain experts

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Generation Linking

Identify suitable data sets as linking targets

Look for similar datasets in http://thedatahub.org/

Discover relationships between data items

Silk Framework LIMES

Validate the relationships discovered

http://aksw.org/Projects/limes http://www4.wiwiss.fu-berlin.de/bizer/silk/

Look for our resources in tools like sig.ma

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Iterative and Incremental Linked Data Life Cycle

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Publication

§  Dataset publication

§  Metadata publication

§  Dataset discovery

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Publication Dataset publication

§  Tools for storing RDF/SPARQL endpoint/Linked Data frontend

-  Virtuoso Universal Server, Jena, Sesame, 4Store, YARS, OWLIM, Talis Platform, Fuseki, Pubby, Linked Data API

§  Store the RDF data in different graphs -  http://example.com/graph/ontology -  http://example.com/graph/dataset -  http://example.com/graph/links

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Publication Metadata Publication

§  VoID allows to express metadata about RDF datasets

§  The PROV Ontology

http://www.w3.org/TR/void/ http://www.w3.org/TR/prov-o/

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Publication Dataset discovery

§  Register the dataset into CKAN Registry, thedatahub.org

§  Generate sitemap files for your dataset, by using sitemap4rdf

§  Submit the sitemap location to Google and Sindice

http://www.w3.org/wiki/TaskForces/CommunityProjects/LinkingOpenData/DataSets/CKANmetainformation http://lab.linkeddata.deri.ie/2010/sitemap4rdf/

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Publication Dataset discovery - Example

http://www.w3.org/wiki/TaskForces/CommunityProjects/LinkingOpenData/DataSets/CKANmetainformation http://lab.linkeddata.deri.ie/2010/sitemap4rdf/

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Iterative and Incremental Linked Data Life Cycle

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Exploitation

Streaming resources

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Exploitation

•  Faceted browser interface.

•  Geospatial visualization using Google Maps and Open Street Maps.

•  Visualization of geometries (LineStrings, Polygons, etc) when using the GeoLinkedData data model.

•  Visualization of statistical data using SCOVO / RDF Data Cube.

map4rdf

https://github.com/boricles/linked-data-visualization-tools

SPARQL

Triplestore

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ToC »  Introduction

» Guidelines for Publishing Linked Data

» Uses Cases

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http://geo.linkeddata.es

1. Specification 2. Modelling

3. Generation 4. Publication & Exploitation

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http://aemet.linkeddata.es/browser_en.html

1. Specification 2. Modelling

3. Generation 4. Publication & Exploitation

Python scritps

250 weather stations (pressure, humidity, etc)

Data from the stations in CSV files in a FTP server

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http://bne.linkeddata.es/graphvis/ http://datos.bne.es/

1. Specification 2. Modelling

3. Generation 4. Publication &

Exploitation

MARC 21 XML records

MARiMbA  

Classification

Annotation

Mapping templates

Relationships

MARiMbA  

Domain experts

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http://webenemasuno.linkeddata.es

1. Specification 2. Modelling

3. Generation 4. Publication & Exploitation

Scenario in the context of tourism and travelling, where the content is aggregated from different platforms. Heterogeneous content (images, travel guides, posts,

videos, news)

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Methodological Guidelines for Publishing Linked Data

Boris Villazón-Terrazas bvillazon@isoco.com

@boricles Slides available at: http://www.slideshare.net/boricles/

Acknowledgements: OEG