Research On Multi-commodity Pick-up And Delievery Vehicle Routing Problem With Split Loads

In the pickup and delivery vehicle routing problem,each customer has different requests for different product types(including pick-up requests and delivery requests).A product obtained at a customer who has a delivery request for a certain product may satisfy a plurality of customers who have a request for picking up the product.At the same time,customers who have a request for pick-up for a certain product can be satisfied by multiple customers with delivery requests.Such problems are widely used in real life,such as the problem of shared bicycle rebalancing,the rebalance of multi-warehousing,etc.,which has strong theoretical research significance and practical application value.An important research direction in the delivery problem has received more and more attention from scholars.This paper studies unpaired pickup and delivery vehicle routing problem from multiple angles,including multiple commodity types,different customer requests split mode,whether the vehicle can be restocked or unloaded in the middle of the vehicle,and the number of vehicles is fixed.The number of warehouses.,The details are as follows:1.The first problem is based on the optimization problem of multi-commodity and unpaired pick-up and delievery vehicle routing problem split and replenishment,considering single carpot and single depot and in the same location.the depot can provide all types of goods.Split mode is the type of pick-up request can be split,the number of each type of item can be split;The type of delivery request can be split,The quantity of each type of item cannot be split.The vehicle can go to the depot for loading or unloading while driving.The goal is to minimize travel costs and fixed vehicle costs.Combining the characteristics of the problem,the mathematical model is established,and the corresponding genetic algorithm is designed to solve the problem.The implementation process of the algorithm is elaborated,including coding method,determination of vehicle initial load,population initialization method,cross strategy,mutation strategy and repair strategy,local search strategy,etc.On this basis,explore solutions to problems at different angles.At the same time carry out related experiments.Including the impact of different fixed vehicle numbers on the problem.Study the import of another split mode,which is the type of pick-up request and delivery request can be split,the number of each type of goods can be split,on problems;The effect of vehicle does not go to the depot to load or unload on the way;The effect of carpot and depot not in the same location.By studying these problems,not only the feasibility and stability of the algorithm are verified,but also the problem is further explored and explored.2.The second question considers single carpot with multiple depot and they are not in the same location.This paper raises the issue of the compatibility of depot and commodities.The problem of multi-commodity and unpaired pick-up and delievery vehicle routing problem with split and replenishment under compatible conditions is studied,that is,the types of goods that different depot can provide are different.The type of goods that the vehicle can load in the depot depends on the type of goods that the depot can provide.The types of goods that the vehicle can unload in the depot are independent of the types of goods that the depot can provide.Incompatibility is the type of good that a vehicle can load and unload in a depot,depending on the type of good the depot can provide.Split mode and the objective function is the same as the first question,and the vehicle can be returned to the carpot halfway.Combining the characteristics of the problem,the mathematical model is established,A specific solution is given for the problem of depot selection and the problem of determining the initial vehicle load when the vehicle departs from the carpot in the case of warehouse and commodity compatibility and incompatibility.The corresponding genetic algorithm is designed to solve the problem.The implementation process of the algorithm is elaborated,including coding method,depot selection problem,determination of vehicle initial load,population initialization method,cross strategy,mutation strategy and repair strategy,local search strategy,etc.On this basis,explore solutions to problems at different angles.At the same time carry out related experiments.Including the impact of different fixed vehicle numbers on the problem.Study the import of another split mode,which is the type of pick-up request and delivery request can be split,the number of each type of goods can be split,on problems;The effect of vehicle does not go to the depot to load or unload on the way;By studying these problems,not only the feasibility and stability of the algorithm are verified,but also the problem is further explored and explored.