| With the rapid development of logistics and trade and the continuous improvement of transportation network in China,multimodal transportation,as an intensive and efficient form of transportation organization,has also been developed rapidly.At present,China has taken the development of multimodal transportation as an important way to build a modern integrated transportation system.China’s vast size and its accelerated comprehensive transportation network also provide good conditions for the development of multimodal transportation.Multimodal transportation is bound to become the main organization of medium and long-distance cargo transportation.In the actual organization process of multimodal transportation,decision-makers,such as shippers,carriers,and transportation managers,have different needs for transportation organization schemes based on their own expectations,which affects the choice of transportation paths and transportation methods.Therefore,comprehensively considering the goals of different decision-making subjects in the optimization of multimodal transportation routes is conducive to integrating social resources,improving the efficiency of multimodal transportation,and maximizing the overall social benefits.This paper considers the optimization of multimodal transportation routes from the perspectives of multiple stakeholders such as shippers,carriers,and transportation managers,and further supplements the problem research system,which mainly includes the following contents.(1)The relevant theories of generalized cost are sorted out,and the applicability of the principles of addition and multiplication in the process of constructing generalized cost model is discussed.Based on the transportation mode selection mechanism,the influencing factors of the generalized cost function including transportation cost,time,capacity,quality,reliability,and environmental protection are analyzed.(2)The decision-making psychology and goals of different decision-making subjects of multimodal transport are analyzed,and the relevant costs and indicators of the goals of different decision-making subjects from three aspects: road,railway and waterway are quantified.Based on the generalized cost model construction principle,a generalized multimodal transportation cost function was established including transportation cost,transportation time value cost,time deviation penalty cost,transportation external cost,transportation security and transportation reliability.(3)A multimodal transportation route optimization model with generalized cost optimization as the goal is constructed,and the optimization goal fully reflects the consideration of the needs of different decision-making subjects.In the model solution,the fuzzy demand variables and non-linear conditions are processed according to the characteristics of the model,and a practical example is designed.The ideal point method is used to solve the problem with LINGO software,and multiple sets of global optimums under different weight combinations are obtained.The solution provides a reference basis for different decision-making subjects.Based on this,the feasibility of promoting the development of multimodal transportation by increasing the speed of rail travel is demonstrated through the sensitivity analysis of the speed of rail travel. |
