Vehicle Routing Problem With Integrated Pickup-and-Delivery Goods

In the past few decades,the fast fashion brand has developed rapidly,which has inspired the research on supply chain management and its related problems.Reliable supply chain management requires the implementation of zero inventory management,and "zero inventory" is a business strategy and inventory management measures that enterprises want to have little or no inventory.The specific meaning of "zero inventory" is that the related products or materials exist in the way of turnover throughout the supply chain.Therefore,considering "zero inventory" in vehicle path problem,the problem can be transformed into inventory allocation.Through the support of existing inventory data and commodity sales forecast,inventory allocation can also be regarded as the problem of vehicle path optimization,that is,reasonable and efficient arrangement of vehicles to transport related products or materials between warehouses.The vehicle routing problem studied in this paper is inspired by the challenge of product allocation faced by a fast consumer retailer in Singapore,which has multiple stores and a warehouse in the city to sell a variety of fast fashion products.Each weekend the retailer forecasts the demand of each product for the next week.To ensure the inventory level equal to the forecast,the retailer schedules a fleet of vehicles to pick up or deliver products from/to each store at the beginning of each week.Shipping products from a store in surplus to another store in shortage is encouraged.For products that cannot be balanced among the stores,they are either picked up or delivered from/to the warehouse,which incurs a handling cost for each unit.The objective is to minimize the total travel distance as well as the total handling cost at the warehouse.This paper first summarizes the research background and significance of the problem,as well as the research on the problem and related problems at home and abroad.Then we established the mathematical model of multi-commodity fetching and delivery problem,and determined the tabu search algorithm as the solution of this model,and designed the neighborhood search method suitable for solving the multi-commodity pickup and delivery problem model.Finally,practical instances and common instances in the corresponding papers are used to carry out experiments.