1. NewRail Simulation Modelling for Analysing Rail Freight Operations Dr Marin Marinov Clare Woroniuk September 2012

2. Outline Systems Approach; Decomposition Approach; Analytical Modelling; Simulation Modelling; Education.

3. Systems Approach Formulation – To detect and formulate the problem; Modelling – To better understand the behaviour of the system under study, its bottlenecks in particular; Evaluation – To analyse the system behaviour through quantitative MOP and find alternative ways to operate the system; Decision – To select the best alternative according to system goals.

4. Decomposition Approach Reduces complexity; Divides the system under study into its components; Studies the systems components in greater detail; Allows modellers to develop a detailed model of the bottlenecks in the system under study; Allows analysts to study in greater detail those components of the system, which malfunction; Corrects the behaviour of the malfunctioning system; Captures the global impact of operations in a network.

5. Analytical Modelling Deterministic Models; Queueing Systems such as: – M/M/m; M/G/m. Queueing Networks such as: – Parallel, in series; open or closed circuit networks.

6. Deterministic Models J. Pachl, where - minimum number of tracks; - average dwell time in minutes per train; - average traffic flow, trains per period.

7. Queueing Systems Expected freight trains in queue (G/G/m queue)

8. Queueing Networks I

9. Queueing Networks II The parameter α j is λ 0 * q 0j, where λ 0 is arrivals from outside with probability q 0j ; The required λ i are obtained by linear equations written for λ j, as follows:

10. Simulation Modelling I SIMUL 8 attributes: Work Entry Points – generate freight trains; Work Centres – replicate where operations with trains are executed; Storage Areas – replicate the limited number of tracks; Work Exit Points – indicate where the freight trains leave the yard; Floating Resources – replicate the yard personnel behaviour.

11. Simulation Modelling II

12. SIMUL 8 attributes: n, Work Entry Points – generate freight trains; n, Work Centres – replicate where operations with trains are executed; n, Storage Areas – replicate the limited number of tracks; n, Work Exit Points – indicate where the freight trains leave the yard; n, Floating Resources – replicate the yard personnel behaviour. Simulation Modelling III

13. Simulation Modelling IV

14. Simulation Modelling V Arena Attributes Freight Trains are represented by entities Flow of the entities through the system can be captured Entities are created by a create module Process Module Decide Module Dispose Module Model Reports

15. Simulation Modelling VI

16. Simulation Modelling VII

17. Simulation Modelling VIII

18. Thank you for your attention Dr Marin Marinov marin.marinov@ncl.ac.uk Clare Woroniuk clare.woroniuk@ncl.ac.uk