Design And Optimization Of The Hub-and-spoke-based Road-rail Intermodal Transportation Network Under Uncertain Conditions

Due to the advantages of cost-saving,high reliability and low-carbon properties,road-rail intermodal transport system,which provides the overall process of freight transportation,has become an important direction for the development of moderm logistics.Developing rail-road intermodal transport system can enhance the efficiency while reducing the cost of logistic networks,motivate the carbon reducing process of freight transport and improve the modernization of intermodal transport systems.Typically,hub-and-spoke is a type of high-efficient network structures.Optimizing the road-rail transport system under hub-and-spoke structure can evidently improve the efficiency and act as a fundamental role in of road-rail transport systems.In the thesis,we construct a novel framework by combining hub-and-spoke structure and road-rail networks.Based on this framework,we address the macroscopic optimization of hub location and commodity routes for road-rail transport systems by synchronously considering the uncertain factors involving benefits,time and reliability,which will provide solid theoretical foundation for multimodal transport systems in the future.Specifically,the main contributions and conclusions are summarized as follows.(1)Hub-and-spoke-based rail-road network design model with uncertain reliability.By using graph theory,we propose a reliability-based optimization approaches based on fuzzy reliability theory,where the transport routes are modeled as arcs,the cities in the network are modeled as nodes and the problem is formulated into a location-routing problem.A hub-and-spoke-based rail-road network design model with uncertain reliability is constructed to maximize the network reliability.By analyzing the mathematical properties,the model is then transferred into an equivalent mixed-integer linear programming model.Further,an improved Tabu search(TS)algorithms is particularly developed according to the specific structures of these models.Finally,numerical experiments based on the data from OR-LIBRARY platform are conducted to verify the correctness and effectiveness of the proposed models and algorithms.(2)Hub-and-spoke-based rail-road network design models with uncertain transport cost,time and demand.Considering the uncertainty of transport cost,transfer cost,hub investment cost,transport time,transfer time and transport demand,we build a mathematical model for the hub-and-spoke-based rail-road network design with uncertain cost-time-demand,which is a bi-objective model for minimizing the expected value of transport cost and the longest transport time between two nodes in the hub-and-spoke-based rail-road network based on techniques of expected values and critical values.Based on the mathematical properties of the models,we design a memetic algorithm(MA)to enhance the computational efficiency to obtain the optimal(near-optimal)solution for the designed transport network.Finally,numerical experiments based on the data from OR-LIBRARY platform are conducted to verify the effectiveness of models and algorithms.