With my students, we have designed and implemented the following (open source) systems:
- GeoTriples. GeoTriples is a tool for transforming geospatial data from their original formats (e.g., shapefiles or spatially-enabled relational databases) into RDF.
- Strabon. This is a fully implemented semantic geospatial database system that can be used to store linked geospatial data expressed in RDF and query them using an extension of SPARQL.
- Ontop-spatial. Do you want to get the most of your relational data combining them with linked geospatial data without converting them to RDF? No problem. Ontop-spatial can create virtual geospatial RDF graphs on top of your geospatial databases.
- Silk. Silk is an open source framework for integrating heterogeneous data sources. We have extended the tool to allow the discovery of spatial and temporal links among datasets. This extra functionality is now part of the default distribution.
- Sextant. This is a Web-based system for the visualization and exploration of time-evolving linked geospatial data and the creation, sharing, and collaborative editing of "temporally-enriched" thematic maps.
- FoXtrot. This is an XML filtering system developed in the Ph.D. thesis of Iris Miliaraki. See our ACM TWEB paper.
- Atlas is a P2P Query Processing system for RDF(S).
- P2P-DIET has been developed by my ex-student Stratos Idreos, who is now a professor at Harvard. The original web site for P2P-DIET is http://www.intelligence.tuc.gr/p2pdiet/.