Meso Network Representation

Network Representation

Mesoscopic simulation uses a representation of the network based on a nodes and sections representation, where the network is translated to a directed graph. In the following example a piece of a network is depicted together with the node and section representation.

There are four geometric elements:

• Nodes: are the nodes and in the mesoscopic representation they are treated as node servers where vehicles are transferred from a section to a turn and then to their next section.

• Turns: are the connections that vehicles use in their path. Turn connections can be defined and refined using the Advanced editor. The turn speed as well as the turn length are used to calculate the turn travel time. All vehicles are assumed to travel without any restriction at a free flow speed in turns. Inside the turn the turn connections can be edited using the advanced editor.

• Sections: Sections are the connectors between nodes. Each section has information about its geometry, number of lanes, speed limits and jam density. The vehicle reaction time for each section can be changed using the reaction time factor in the Section Editor. Solid lane lines and pedestrian crossings are not considered. On/off-ramps are considered. Internally the section is cut in order to have different segments with different number of lanes.

• Centroids: are the source of vehicles. They are used to generate vehicles in the simulation.