1.1 RTSKG Ontology RTSKG Ontology The RTSKG ontology is the unified schema of the Rail Transit Station Knowledge Graph (RTSKG), a dataset that explicitly models the spatial and semantic interactions among different kinds of urban entities. It defines ten classes and nineteen relations. Shutong Zhu Tianxing Wu Runfeng Liu Yuang Gu Xuan He Yuan Zhu Southeast University 2025-11 2026-06 This ontology is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License (CC BY-SA 4.0). rtskg https://w3id.org/rtskg/ontology/ poi_locates_at_station_area Models the location relation between a POI and a station area. poi_locates_at_block Models the location relation between a POI and a block. station_area_locates_at_borough Models the location relation between a station area and a borough. station_area_locates_at_functional_area Models the location relation between a station area and a functional area. block_locates_at_borough Models the location relation between a block and a borough. block_locates_at_functional_area Models the location relation between a block and a functional area. functional_area_locates_at_borough Models the location relation between a functional area and a borough. borough_is_adjacent_to_borough Models the adjacency between two boroughs. functional_area_is_adjacent_to_functional_area Models the adjacency between two functional areas. road_intersects_borough Models the intersection between a road and a borough. road_intersects_functional_area Models the intersection between a road and a functional area. road_intersects_station_area Models the intersection between a road and a station area. station_area_intersects_block Models the intersection between a station area and a block. station_area_intersects_station_area Models the intersection between two station areas. block_intersects_station_area Models the intersection between a block and a station area. station_area_belongs_to_station Models the non-geographic relation in which a station area belongs to a station. station_belongs_to_line Models the non-geographic relation in which a station belongs to a rail transit line. poi_has_poi_category Models the non-geographic relation in which a POI has a POI category. road_has_road_category Models the non-geographic relation in which a road has a road category. geometry The geometry of a feature, encoded as an OGC Well-Known Text (WKT) literal in the WGS84 coordinate reference system. walking_time_minutes The walking time, in minutes, used to construct the station area as the region reachable from a station within this time (e.g., 5 or 10 minutes). Borough An administrative borough describing high-level administrative boundaries of a city. Functional Area A functional area representing the subdivision of a city according to its function (e.g., residential areas). Station The rail transit station, which serves as a transport hub for passengers to board or alight from the rail transit vehicles like subway train. Rail Transit Station Station Area The region accessible from a rail transit station within a specified walking time. Line The rail transit line, which is a sequence of connected stations. Rail Transit Line Road The road segment in a city. Block The urban block, which is a fine-grained spatial unit that constitutes the fundamental element of the physical structure of urban areas. POI A point of interest (POI), which represents the basic functional units in a city. Point of Interest POI Category The category of a POI, which characterizes the function of the POI. Point of Interest Category Road Category The category determined by the hierarchy or function of the road.