Name: Jim Jones Making the Web of Data Available via Web Feature Services Jim Jones, Werner Kuhn, Carsten Keßler and Simon Scheider 17th AGILE Conference 2014, Castellón, Spain

Name: Jim Jones Making the Web of Data Available via Web Feature Services 2

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

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

Name: Jim Jones 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) WFS Issues We propose an LOD based solution called LOD4WFS!

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

Name: Jim Jones 7 Linked Open Data Making the Web of Data Available via Web Feature Services

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

Name: Jim Jones. LOD Cloud Geometry Table of Contents

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

Name: Jim Jones 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? Making the Web of Data Available via Web Feature Services

Name: Jim Jones 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. Making the Web of Data Available via Web Feature Services

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

Name: Jim Jones GIS Client LOD Cloud From this...

Name: Jim Jones Making the Web of Data Available via Web Feature Services 15 Data Access and Format Standard Data Access Federated Data Access

Name: Jim Jones Making the Web of Data Available via Web Feature Services 16 Standard Data Access Triple Store LOD4WFS Adapter SPARQL

Name: Jim Jones Making the Web of Data Available via Web Feature Services 17 Standard Data Access Data Structure (Including Meta-Data) Named Graph TitleDescriptionFeatures GeometriesAttributes (TOC)...

Name: Jim Jones Making the Web of Data Available via Web Feature Services 18 Standard Data Access Data Structure 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 " "^^xsd:integer ; dc:description "Recife"^^xsd:string ; geo:hasGeometry my:GEOMETRY_RECIFE. my:GEOMETRY_RECIFE a geo:Geometry ; geo:asWKT " POLYGON (( , , ))"^^sf:wktLiteral.

Name: Jim Jones Making the Web of Data Available via Web Feature Services 19 Federated Data Access LOD Cloud LOD4WFS Adapter Customized SPARQL

Name: Jim Jones Making the Web of Data Available via Web Feature Services 20

Name: Jim Jones Making the Web of Data Available via Web Feature Services 21 DBpediaOrdnance Survey

Name: Jim Jones Making the Web of Data Available via Web Feature Services 22

Name: Jim Jones Making the Web of Data Available via Web Feature Services 23

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

Name: Jim Jones 25 Making the Web of Data Available via Web Feature Services Test Datasets Test ScenarioSHP Size DB Size DB RecordsTurtle fileTriples 1 – Brazilian Cities11.2 MB16 MB MB – Amazon Rivers45 MB55 MB MB – Amazon Vegetation MB183 MB MB Source: Brazilian Institute of Geography and Statistics

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

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

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

Name: Jim Jones Conclusions 29 Making the Web of Data Available via Web Feature Services

Name: Jim Jones Future Work (Potential for growth!) 30 - Implement spatial queries (GeoSPARQL) - Implement WFS-T (Insert, Update, Delete). - Publish WFS contents as LOD! 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 Making the Web of Data Available via Web Feature Services

Name: Jim Jones 31 Obrigado! Making the Web of Data Available via Web Feature Services