Interoperable-data
commented
3 weeks ago
the era:elementPartOf property allows the implementation of several topological layers. It has the domain and the range defined as era:TopologicalObject to allow composition at different levels and for different types of subclasses. With this approach you can even say that a era:LinearElement is a era:elementPartOf an era:LinearElementLink. Previous sentence can be read as: a track is part of an operational point.
The technical characteristics of any of the railway elements are not defined as properties of era:TopologicalObject class and its subclasses, but on the era:InfrastructureObject which is the functional/implementation part of the model.
Most of the geometry attributes (gradients, cants, curves), positioning of the infrastructure objects (signals, balises, etc.) make sense only at microscopic level of the topology graph (LinearElements). Other abstraction levels represent aggregations, so the mentioned information can be assigned to them, but as "average, max/min etc" values = as different objectProperties. As a metapher: we can assign objectProperty "temperature" to a microscopic element (patient) and to a macroscopic (hospital). But they mean totally different aspects.
To allow precise assignment (only to dedicated LinearElements at micro-level) of precise information (with mm-precision) we would need a dedicated class e.g. MicroLinearElement as a subClassOf LinearElement. In CCS/TMS this class is called TrackEdge.