Simulation of merge junctions in a dynamically entrained automated guideway transit system
Merge junctions and intersections are the principal capacity limiters and sources of delay in automated guideway transit (AGT) networks. The capacity and delay performance of the merge junctions must be thoroughly understood before an AGT network can be designed. This paper describes the modeling and event-structured Monte Carlo simulation of a single merge junction, having two input lanes and one output lane, operating in a quasi-synchronous network. The simulation described here differs from previous merging models by permitting slots to be of variable length to accommodate trains of different lengths, and allowing unlimited maneuvering of trains (if needed). It has the unique ability to represent the operation of a special, newly devised concatenating merge, which permits trains arriving on separate input lanes to combine themselves into a longer train at the merge.
 The simulation logic which is used to represent special features of merge performance (flow compressibility, upstream propagation of disturbances, etc.) is explained, and the implementation using GASP IIA is described. The statistical considerations underlying the experimental design are discussed and some sample diagnostic outputs displayed.