Multi-point To Multi-point Multi-task Fourth Party Logistics Routing Problem Considering Tardiness Risk

The development of economic globalization has promoted the rapid development of the logistics industry and brought new opportunities and challenges to the logistics industry.Since the 21st century,the overall scale of China's logistics industry has been expanded,and the conditions and environment of the development have been greatly improved,which laid a solid foundation for the further development of logistics industry.Logistics is an important part of commodity trading.The development of logistics industry can help to speed up the cash flow and commodity circulation,reducing logistics costs,thereby enhancing the quality of the national economy.It can help to improve the proportion of the service industry and change the mode of economic development.It can help to ease traffic congestion and achieve harmonious development of social and economic.The Fourth Party Logistics(shorted for 4PL)service provider is a supply chain integrator,which provides customers with a set of optimal logistics supply chain solutions,reducing operation costs and improving the operation efficiency of the entire logistics supply chain.At the same time,it makes up for the Third Party Logistics(shorted for 3PL)service providers in the lack of management capacity.Transportation is an important part of the logistics process and the choice of path is related to the efficiency and cost.The Fourth Party Logistics Routing Problem(shorted for 4PLRP)chooses the 3PL and path meanwhile to satisfy the transportation request and reduce the transportation time and cost.In the past,the research on the tardiness risk is based on the single logistics task.But in actual situations,there are multiple logistics tasks in the same logistics network,and 4PL should serve multiple tasks at the same time.Based on multi-point to multi-point multi-task problem,the main work of this thesis is as follows:Firstly,according to the characteristics of multi-point to multi-point multi-task 4PLRP considering tardiness risk,the Value-at-Risk(VaR)is introduced to measure tardiness risk.On the one hand,some 3PL suppliers' transportation cost and time are relatively low.With a competitive advantage and strong capacity,they can transport many tasks at the same time.So the multi-point to multi-point multi-task reusable mathematical model is established.On the other hand,considering the internal administrative requirements for 3PL selection,each 3PL supplier can serve only one task.So the multi-point to multi-point multi-task non-reusable model is established.Two models are nonlinear and aim to minimize the maximum value of all tasks'tardiness risk.Secondly,due to the NP-hard characteristic of optimization problem,the hybrid ant colony algorithm based on the basic ant colony algorithm is designed.The dynamic adjustment strategy is introduced to guide ants to explore new paths and avoid local optimum.The max-min pheromone mechanism in the pheromone update strategy is also introduced,so the algorithm's design process is described in detail.Finally,aiming at seven nodes,fifteen nodes and thirty nodes problems,the thesis studies four aspects:algorithm parameter setting,comparison of different algorithms,setting of model parameters and comparison of different models:(1)based on the M-M-M 4PLRPTR reusable situation with seven nodes,the thesis introduces the parameters' adjustment process of hybrid ant colony algorithm,and finds the optimal parameters combination for three scale problems.(2)The basic ant colony algorithm and the hybrid ant colony algorithm are used to verify the advantages of hybrid ant colony algorithm for solving such problems.(3)The model parameters are studied.The influence of confidence level ? and delivery cost requirement C0 on the tardiness risk and route choice is analyzed.(4)Based on the different confidence level,the reusable model and non-reusable model for three scale problems are analyzed.The thesis draws relevant conclusions:the hybrid ant colony algorithm has obvious advantages in solving such problem;tardiness risk increases with the increase of confidence level beta;in a certain range,tardiness risk decreases with the increase of the total cost;under the same condition,compared to non-reusable situation,reusable situation can get smaller tardiness risk.These conclusions guide the decision-making process in different situations.