Algorithm for the Transportation Network Nodes Aggregation Using Fuzzy Logic

In many situations, the model of the transportation network contains a very large number of nodes, so the algorithms operating on such a model may be too time-consuming. Therefore there is a need to simplify the model by reducing the number of nodes. The simplest approach using the physical neighbourhood of the nodes and then aggregation of nearby nodes may be insufficient, because it does not take into account the different roles played by the nodes subject to the merger. Some of them have local significance and can be aggregated without disturbing the traffic flows across the whole network. For other nodes traffic flows associated with geographically distant nodes can be much larger than the local flows. Nodes of this kind should not be aggregated with their neighbours. This paper presents an algorithm for grouping the transportation network nodes using fuzzy logic, which processes the qualitative characteristics of nodes.