Semantic 3D City Database — An enabler for a dynamic geospatial knowledge graph

This paper presents a dynamic geospatial knowledge graph as part of The World Avatar project, with an underlying ontology based on CityGML 2.0 for three-dimensional geometrical city objects. We comprehensively evaluated, repaired and refined existing to produce improved version that could pass the necessary tests complete unit test development. A corresponding data transformation tool, originally designed work alongside CityGML, was extended. allowed original into form semantic triples. compared various scalable technologies this storage chose Blazegraph™ it provided required search functionality. also evaluated hardware solutions file systems using publicly available Charlottenburg in Berlin, Germany working example. structural isomorphism schemas OntoCityGML Tbox be transformed without loss information. Efficient algorithms us retrieve building from any point coordinates. use named graphs namespaces partitioning ensured system performance stayed well below its capacity limits. achieved by evaluating dedicated capable hosting expansible systems, which strengthened architectural foundations target system.