Copyright © 2014 Open Geospatial Consortium.
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f2n:52N_ConflationExecution20140305 prov:qualifiedUsage [ a prov:Usage ;
prov:entity ows10:distance1 ; prov:hadRole ows10:conflationThreshold
] .
7.5.3.4 Bundle
Everything was documented by Arne at 2014-03-05 10:22. In W3C PROV specification, a bundle is defined as a provenance of the provenance information.
8 Using W3C PROV into a Conflation WPS
Conflation is understood as the process of unifying two or more separate datasets, which share certain characteristics, into one integrated all-encompassing result.
In the OWS-10 interoperability experiments, WPSs were used to generate conflated objects under user demand. The response of the WPSs was a combination of the
conflated features instances and their property values encoded in GML and the provenance of the same features encoded in RDF triples. GML data was stored in WFS-T
services and RDF information stored in its transactional triple store databases.
In the developed scenarios, the conflation process is not completely automated, i.e. the results of the conflation WPS is no automatic uploaded to a WFS-T. Instead, the user gets
a chance to inspect the conflated result and decide whether to upload it or rerun the process with different parameters.
These are the components used in the architecture see Figure 15: Client PIXIS: Presents source 1, source 2, features result of the conflation and
provenance of the conflated features to the user. It also allows the user to request a new conflation of some objects to the WPS and it is responsible to send the
conflation result to the WFS-T and the SPARQL Server once visually inspected and validated by the user.
WFS Source1: Contains a feature collection from source 1. These are the features to be conflated. E.g. USGS
WFS Source2: Contains a feature collection from source 2. These are the features that will be identified as the same as some in Source 1 and they can be conflated.
E.g. OSM Conflation WPS: Conflation process that generates a new set of conflated
features. Responds back to the Client PYXIS SPARQL Server: Stores provenance information entities, activities and agents at
dataset level feature collection and at the individual feature and attribute level
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Copyright © 2014 Open Geospatial Consortium.
using the W3C PROV and RDF encoding. Individual feature provenance is linked to the features by id
WFS-T: Stores the resulting conflated features and their attributes encoded in GML
Figure 15 — Components involved in the conflation process
In the component diagram we see that the client is responsible for executing the WPS Conflation process but also to deal with the WPS result that contains both the GML and
the W3C PROV and to send the final GML features to the WFS conflated layer and the W3C PROV in the SPARQL server.
8.1 User assisted conflation process
In the user assisted conflation process scenario, several steps are required to complete the task of generating a conflated result. Figure 1 UML diagram explains the sequence of
steps that where implemented in this use case.
cmp Feature lev el Prov enance Components Diagram
Conflation WPS WFS Source1
WFS Source2 Client PIXIS
WFS Conflated SPARQL Serv er
Client
WFS
WFS WPS
SPARQL-T
WFS-T WFS
WFS
