1 / 31

Making the Web of Data Available via Web Feature Services

Discover the LOD4WFS solution for efficient data access, storage, and analysis. Learn about Linked Open Data and the merge between GIS and LOD technologies. Explore performance and interoperability issues resolved by LOD4WFS.

pbenjamin
Download Presentation

Making the Web of Data Available via Web Feature Services

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Making the Web of Data Available via Web Feature Services 17th AGILE Conference 2014, Castellón, Spain Jim Jones, Werner Kuhn, Carsten Keßler and Simon Scheider jim.jones@uni-muenster.de

  2. 2 Making the Web of Data Available via Web Feature Services

  3. Shapefile Database 3 Making the Web of Data Available via Web Feature Services Web Feature Service (WFS) GIS Client WFS Server KVP XML (GML) - Data Analysis - Spatial Operations - Generate New Maps ...

  4. Making the Web of Data Available via Web Feature Services 4 Number of hospitals in the cities around the flooding area Where to get this information?

  5. WFS Issues Low Interoperability Data stored in silos (e.g. databases, shapefiles) and external sources can't be used in one query. inefficient maintenance Table of Contents not easily updated (e.g. add new data means add new database fields, which has to done by a GIS expert / DBA) We propose an LOD based solution called LOD4WFS!

  6. 6 Making the Web of Data Available via Web Feature Services Outline WFS and LOD LOD4WFS Adapter Solution Evaluation Conclusion and Future Work

  7. Making the Web of Data Available via Web Feature Services 7 Linked Open Data

  8. Making the Web of Data Available via Web Feature Services 8 Linked Open Data Raw data, now! “linked open data describes a method of publishing structured data so that it can be interlinked and become more useful.” Tim Berners-Lee

  9. . Table of Contents Geometry LOD Cloud

  10. Making the Web of Data Available via Web Feature Services 10 Research Question GIS Client LOD Cloud How to efficiently make geographic LOD datasets discoverabele by current GIS?

  11. Making the Web of Data Available via Web Feature Services 11 Related Issues How to read geographic LOD without modifying the current GIS? How to develop a solution that is both platform and GIS independent? Is performance an issue when querying geographic LOD datasets?

  12. Making the Web of Data Available via Web Feature Services 12 Proposed Solution GIS Client LOD Cloud LOD4WFS Adapter Creates an intermediate WFS layer “on top” of the LOD cloud Provides LOD datasets in a format understood by GIS based on OGC Standards.

  13. LOD4WFS overview in 6 Steps... Making the Web of Data Available via Web Feature Services 13 2. Adapter translates GIS request to SPARQL and performs query. 3. Triple Store processes SPARQL query. 1. Client sends request KVP SPARQL RDF XML (GML) LOD4WFS Adapter Triple Store GIS Client 6. GIS gets the WFS document. 5. Adapter translates result set and delivers WFS document to the GIS. 4. Triple Store returns SPARQL result set.

  14. From this... GIS Client LOD Cloud

  15. 15 Making the Web of Data Available via Web Feature Services Data Access and Format Federated Data Access Standard Data Access

  16. 16 Making the Web of Data Available via Web Feature Services Standard Data Access SPARQL LOD4WFS Adapter Triple Store

  17. 17 Making the Web of Data Available via Web Feature Services Standard Data Access Data Structure (Including Meta-Data) Named Graph Features Title Description ... Geometries Attributes (TOC)

  18. 18 Making the Web of Data Available via Web Feature Services Standard Data Access Data Structure <http://ifgi.lod4wfs.de/graph/municipalities> dct:title "Brazilian Municipalities"^^xsd:string ; dct:abstract "Municipalities of the Brazilian Federal States."^^xsd:string ; dct:subject "municipalities boundaries"^^xsd:string . my:FEATURE_RECIFE a geo:Feature ; rdf:ID "2611606"^^xsd:integer ; dc:description "Recife"^^xsd:string ; geo:hasGeometry my:GEOMETRY_RECIFE . my:GEOMETRY_RECIFE a geo:Geometry ; geo:asWKT "<http://www.opengis.net/def/crs/EPSG/ 0/4326> POLYGON ((-35.0148559599999984 -8.0564907399999992, -34.9939074400000010 -8.0493884799999993,... -35.0148559599999984 -8.0564907399999992))"^^sf:wktLiteral .

  19. 19 Making the Web of Data Available via Web Feature Services Federated Data Access Customized SPARQL LOD4WFS Adapter LOD Cloud

  20. 20 Making the Web of Data Available via Web Feature Services

  21. 21 Making the Web of Data Available via Web Feature Services DBpedia Ordnance Survey

  22. 22 Making the Web of Data Available via Web Feature Services

  23. 23 Making the Web of Data Available via Web Feature Services

  24. Shapefiles PostGIS Solution Evaluation (preliminary results) Making the Web of Data Available via Web Feature Services 24 Vocabularies: GeoSPARQL and Dublin Core Geometry Encoding: Well Known Text (WKT) Ubuntu Server 12.04 LTS Linux 3.2.0-58-generic (amd64) Intel(R) Xeon(R), CPU E5530 @ 2.40GHz, Dual Core 8GB RAM shp2rdf.R Geoserver (WFS) Parliament Fuseki OWLIM Lite

  25. Making the Web of Data Available via Web Feature Services 25 Test Datasets Source: Brazilian Institute of Geography and Statistics http://www.ibge.gov.br

  26. PostGIS cURL GetFeature Request – Scenario 1 (Brazilian Cities – 86988 Triples) Geoserver ~38.2 sec. ~38.85 sec. OWLIM Lite ~38.87 sec. ~38.7 sec. LOD4WFS Parliament Fuseki

  27. PostGIS cURL GetFeature Request – Scenario 2 (Amazon Rivers – 359206 Triples) Geoserver ~2:36.2 min. ~2:38.0 min. OWLIM Lite ~2:38.15 min. ~2:38.11 min. LOD4WFS Parliament Fuseki

  28. PostGIS cURL GetFeature Request – Scenario 3 (Amazon Vegetation – 703497 Triples) Geoserver ~8:35.6 min. ~8:39:0 min. OWLIM Lite ~8:44:7 min. ~8:44:0 min. LOD4WFS Parliament Fuseki

  29. Making the Web of Data Available via Web Feature Services 29 Conclusions

  30. Making the Web of Data Available via Web Feature Services 30 Usage of LOD in GIS is perfectly feasible - LOD4WFS provides a suitable platform for bridging GIS and LOD and querying distributed sources. - The proposed approach enables thematic queries to compose the geometries' table of contents. - Preliminary tests showed that current triple stores provide competitive speed compared to databases Future Work (Potential for growth!) - Implement spatial queries (GeoSPARQL) - Implement WFS-T (Insert, Update, Delete). - Publish WFS contents as LOD!

  31. Making the Web of Data Available via Web Feature Services 31 Obrigado! https://github.com/lodum/lod4wfs

More Related