Rail-bound Transport Research Articles

The blocking job shop with rail-bound transportation

The blocking job shop with rail-bound transportation (BJS-RT) considered here is a version of the job shop scheduling problem characterized by the absence of buffers and the use of a rail-bound transportation system. The jobs are processed on machines and are transported from one machine to the next by mobile devices (called robots) that move on a single rail. The robots cannot pass each other, must maintain a minimum distance from each other, but can also "move out of the way". The objective of the BJS-RT is to determine for each machining operation its starting time and for each transport operation its assigned robot and starting time, as well as the trajectory of each robot, in order to minimize the makespan. Building on previous work of the authors on the flexible blocking job shop and an analysis of the feasible trajectory problem, a formulation of the BJS-RT in a disjunctive graph is derived. Based on the framework of job insertion in this graph, a local search heuristic generating consistently feasible neighbor solutions is proposed. Computational results are presented, supporting the value of the approach.

Applications of real‐time speed control in rail‐bound public transportation systems

This study gives an overview on applications of speed optimisation as one control measure for intelligent traffic management in rail-bound public transportation systems. The concept of operational target points and target windows is introduced. Speed and dwell time control are used to reach these targets, thereby improve throughput through system-related bottlenecks and reduce energy consumption. Different rail-bound transportation systems are compared and requirements for the application of speed control are derived. Case studies for three different rail-bound passenger transportation systems are presented that demonstrate the potential effects of these control methods on energy consumption and timetable deviation. These control strategies can be implemented using driver advisory systems (DAS) or fully automatic train operation (ATO).