Construction Of Maritime Transport Network And Allocation Of Capacity Resources Based On The Theory Of Hub And Spoke

In recent decades,the container shipping industry has undergone consolidation and relationship restructuring through mergers,acquisitions,or bankruptcy.The complexity of the restructuring of shipping enterprises lies in how to reconfigure the maritime network and integrate shipping resources.Nowadays,the shipping market is in the recovery stage,the scale of container liner shipping market is expanding,and shipping enterprises have joined shipping alliances to form communities of interest,to jointly dispatch ships through sharing agreements,and to re-plan and reorganize shipping capacity on trunk and feeder transportation route networks.This paper studies the construction of shipping network and allocation of capacity resources after the restructuring of shipping assets,discusses the optimization of container shipping network under the competitive environment,reasonably determines the location of hub ports and the allocation of feeder ports,considers container transshipment and port loading and unloading operations,designs ship route transport paths and matches suitable ship types to achieve the minimization of total cost of shipping network optimization and ship deployment.The main research work in the full paper is as follows:1.In response to competition issues arising from the restructuring of shipping companies,the,firstly,the leader shipping alliance A constructs a p-hub median model with the objective of having the lowest cost of operating its own network.Subsequently,the follower shipping alliance B starts to lay out its maritime network and constructs a maximum market share model,aiming to compete with the leader for more market share at a lower cost.Secondly,the leader shipping alliance A realises the existence of competition and takes into account the possible reaction of the follower shipping alliance B before layout,building a bi-level planning model for pre-empting the market.Finally,based on the structural characteristics of the proposed bi-level model,it is linearised into a single-level model using the minimal great regret method,and a minimal great regret value model is proposed.The model is solved using CPLEX and the ALNS algorithm is proposed for the solution,which is tested by computing examples.The impact of discount factors and changes in the number of hubs on the optimal design of hub-and-spoke maritime networks in a competitive environment is analysed to guide shipping companies to capture more market share.A comparative study of static and dynamic competitive locational selection shows that when leaders are aware of the existence of competition in the maritime market,hub port layouts take into account the possible hub port decisions of followers beforehand and lay out key hub port locations in advance to capture more market share.2.To address the capacity allocation problem of container shipping network,container transshipment,route selection and port handling are considered comprehensively,with the objective of minimizing the total operating cost of shipping enterprises.Firstly,based on the segmental speed adjustment strategy,the liner route allocation problem of multiple vessel types on multiple routes is optimised and a mixed integer non-linear programming model is established.Secondly,the non-linear function is used to consider the influence of ship load and speed on the fuel consumption of container ships.According to the concavity of the function,the linear outer-approximation algorithm and the improved piecewise linear approximation algorithm are used to linearise the non-linear constraints respectively,and the mixed integer linear programming route allocation model is constructed.Finally,the model is solved by using CPLEX,and the study shows that the capacity of own ships and alliance partner ships is fully utilised to achieve the matching of volume and capacity and minimise the total operating cost of shipping enterprises.3.The three-stage optimization of container shipping network and ship deployment based on the hub-and-spoke theory is divided into four sub-problems: hub port location problem,feeder port allocation problem,route path planning problem and ship resource allocation problem,and the decision is made in stages according to the idea of divide and rule.Firstly,a three-stage optimisation model is constructed and solved using CPLEX.Secondly,a three-stage optimisation algorithm of "hub port location-route path optimisation-feeder port reallocation" is designed based on the phased optimisation strategy to solve the large-scale problem.In the first stage,the set of hub ports and the set of feeder port assignments are obtained through a variable neighbourhood search algorithm.In the second stage,the nearest neighbour algorithm is used to optimise the feeder route paths and allocate vessels to the feeder ports for vessels departing from each hub port.In the third stage,the feeder ports are reallocated and the nearest neighbour algorithm in the second stage is invoked to optimise the feeder route path and route allocation for a subset consisting of all feeder ports allocated to the same hub port.Finally,the analysis of the algorithm shows that through multiple iterations of the second and third phases,a solution with lower total cost of shipping network optimisation and vessel deployment is finally obtained.4.Integrated optimization of container shipping network and ship deployment based on hub-and-spoke theory.Firstly,the four sub-problems of hub port location,feeder port allocation,route path optimization and ship deployment are integrated to ensure the global optimality of the optimization study,and the integrated solution model of maritime network optimization and ship deployment system is established and solved by using CPLEX.Secondly,a bi-level intelligent algorithm cooperation model is designed,i.e.the upper-level algorithm is responsible for hub port location and feeder port allocation,while the lower-level algorithm is responsible for route path optimisation and route ship allocation optimisation,and a hybrid random key genetic algorithm is proposed through the division of labour between the upper and lower levels to form a hierarchical relationship.Finally,a hybrid local search algorithm is proposed for algorithm comparison study.The analysis shows that the Baltic case is able to obtain a lower total cost solution for shipping network optimisation and ship allocation decisions.In the West African case,due to the increase in the number of port nodes and the increase in the complexity of the solution,the three-stage optimisation also results in a lower total cost solution for shipping network optimisation and ship deployment,thus verifying the effectiveness and applicability of the three-stage optimisation and the integrated optimisation.The research in this paper provides a theoretical research basis and algorithm implementation for maritime network optimization and ship deployment based on the hub and spoke theory,bringing into play the economics of the hub and spoke network structure,providing theoretical and methodological guidance for shipping enterprises’ decisions on hub port location,route network design,ship calling port sequence and capacity resource allocation,and creating greater benefits for shipping enterprises.