A Multi-Objective Tri-Level Algorithm for Hub-and-Spoke Network in Short Sea Shipping Transportation

Hub-and-Spoke (H&S) network modeling is a form of transport topology optimization in which joins are connected through intermediate hub nodes. The Short Sea Shipping (SSS) problem aims to efficiently disperse passenger flows involving multiple vessel routes and intermediary hubs passengers transferred their final destination. contains elements the Travelling Salesman, with different levels among islands, making it more demanding than typical H&S one, as selection within nodes shortest islands internal goals. This work introduces multi-objective tri-level algorithm for General Network (GNSSS) reduce travel distances transportation costs while improving quality user satisfaction, mainly by minimizing hours spent on board. analysis performed at three decisions: (a) node assignment, (b) island-to-line (c) island service sequence each line. Due magnitude complexity problem, genetic employed implementation. performance has been tested evaluated several real simulated case studies sizes operational scenarios. results indicate that provides rational solutions accordance desired sub-objectives. consideration leads quite scattered solution space, indicating necessity employing formal methods. Typical Pareto diagrams present non-dominated varying range 30 percent terms total distance traveled 50 relation cumulative hours. Evaluation further satisfactory result stability (repeatability) computational time requirements. In conclusion, tool assisting operation planning decisions shipping companies directions cost reduction traveler upgrade. addition, model can be adapted other applications supply chain.