Multi-Warehouse Heterogeneous Fleet Vehicle Routing Problem With Considering Central Warehouse

The modern logistics industry is an important component of the modern economic system.In recent years,the expenditure of the logistics industry in the total social expenditure has improved,but the overall situation is still not idea.enterprise competitiveness has been reduced because of the high transportation costs and the continuously increasing storage costs.As the market competition becomes more and more intense,enterprises pay more and more attention to reducing logistics costs and rapid decision-making,the research of vehicle routing problem and the development of the solution application programs have become a practical strategy for this problem.The development of informatization and logistics globalization has made the characteristics of the international logistics companies' central warehouse more prominent.And the same-city/cross-city freight of third-party logistics has gradually become the main park of cargo transportation too.Therefore,the paper study the multi-warehouses heterogeneous vehicle routing problem with considering the central warehouse and the same-city/cross-city multi-model vehicles,and the following work has been completed:First of all,this paper constructed a new mathematical model.By merging the multi-warehouse VRP and the two-echelon VRP,the mathematical model studies the priority of the central warehouse in the multi-warehouse pickup.Then,this paper studies the same-city/cross-city freight of third-party logistics.The vehicle's loading volume and weight,loading category and usage cost vary with the vehicle model.By defining the vehicle travel cost of the same city/cross-city freight and the cost accounting method of the secondary warehouse transfer center warehouse,the vehicle travel cost and the storage and transfer costs of the goods are set in the objective function.In addition,the constraints for the loading of vehicles and cargoes of various models are also set.Therefore,the model studied the priority delivery of the central warehouse and the heterogeneous fleets of same-city/cross-city freight of third-party logistics,to minimize the objective function of the total cost of delivery.Secondly,this paper improves and designs the solving algorithm.Combining the advantages of the deep search of the variable neighborhood search algorithm and the global optimization of the genetic algorithm,this paper designs a hybrid variable neighborhood genetic algorithm.In the algorithm design,in order to enable the population to present better individuals in the early stage,the scanning algorithm is combined when initializing the population.The 2-opt * and Cross-Exchange neighborhood strategies between routes can better exchange line terminal warehouses,which has the advantage of quickly obtaining the optimal solution for the central warehouse MDHFVRP model proposed in this paper.Then,the problem scale is divided into three scales of 15,40,and 60,and numerical experiment analysis is performed.The experimental results show that the hybrid variable neighborhood genetic algorithm is superior to the traditional algorithm.And as the problem size increases,the improvement of the algorithm increases.Finally,an example application analysis is carried out in combination with a large international logistics company.Thirdly,this paper designs and develops a solution application for central warehouse MDHFVRP.Through the needs analysis of business process and system performance,the presentation layer,business logic layer and database of the application program are designed,and then the view module,Gaode API solution engine and output result module are implemented.In summary,this paper solves the problem of multi-warehouse heterogeneous fleet vehicle routing problem with considering the central warehouse.The research results and conclusions will be able to provide the necessary theoretical support and decision support for the logistics improvement of related logistics companies.Completed the vehicle routing problem solving application program that input order data and output the car dispatching results.