Copyright © 2011 Open Geospatial Consortium.
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7.1 Component Implementations
Participants of the CCI thread provided the following components in order to implement the CCI architecture:
Web GUI Clients provided by Compusult and ESRI CSW Services provided by Compusult
CSW-ebRIM Portrayal Registry provided by Carmenta FPS provided by Carmenta
WFS USGS provided by CubeWerx WFS NGA provided by Interactive Instruments GmbH
Semantic mediator provided by Luciad Knowledge Base and SPARQL server provided by Envitia Ltd.
8 Semantic Mediation Approach
As illustrated in the architecture diagram, there are at least two source datasets and each dataset has an ontology associated with its data model. The semantic mediator uses a
common model to mediate between the two or more source models. The following approaches were identified as candidate formulae for defining the common model:
Option 1: Create a new common model A new RMM would be created as the intersection of the NGA and USGS models
NGA model would map to the RMM. USGS model would map to the RMM.
Option 2: Use NGA Model as the Common Model The common model for this thread would be the NGA model, since it has portrayal
symbols and rules already defined for some feature types The USGS model would be mapped to the common model, i.e. the NGA model in
this case. Two WFS services would be available from the semantic mediator services
o WFS based on NGA model serving NGA data
o WFS based on NGA model serving USGS data
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Copyright © 2011 Open Geospatial Consortium.
Option 3: Use NGA Model as starting point for the Common Model augmented as needed from USGS model.
The common model for this thread, referred to as the Surrogate RMM RMM-S, would be based on the TDS model
Mapping to be done are as follows: o
TNM - RMM-S o
TDS - RMM-S o
RMM-S - TNM o
RMM-S- TDS Four WFS services would be available:
1. WFS based on NGA TDS model serving NGA data - provided directly by NGA 2. WFS based on NGA TDS model serving USGS data - provided by semantic
mediator 3. WFS based on USGS TNM model serving NGA data - provided by semantic
mediator 4. WFS based on USGS TNM model serving USGS data - provided directly by
USGS
The CCI thread selected Option 3, which defines a common model as the NGA TDS model augmented by that subset of the USGS TNM model that is not covered by the TDS.
8.1 Semantic Description of Data Models
Kategori