The Optimization Study Of Railway Express Freight Pick-up & Delivery Process

Pick-up and delivery is an indispensable link in the transportation of railway express freight,then,it is urgent and necessary to do a good job in accessing this key link to improve the efficiency of pick-up and delivery service if railways developed a full logistics services in order to fight for freight market share.Therefore,it is of great practical significance to study how to improve the efficiency and service quality of pick-up and delivery service and how to attract a large number of customers to choose railway as a safe,fast and Grand Canal way of transporting goods.For railway express freight transportation,previous studies have focused on express freight pricing,optimization of express freight transportation networks,organization of express freight transportation,express freight markets and development of express freight products.There is also a corresponding study for pick-up and delivery of railway express freight(i.e.the station-to-door and door-to-station transportation of railway express freight),however,only considering the optimization of the weight of goods is obviously biased.On the basic of previous description,this paper makes a corresponding exploration and research focus on the service of pick-up and delivery optimization at the same time.Based on the analysis of the organization factors affecting the pick-up and delivery of express freight,this paper conducts analyze study and optimization of the railway express freight pick-up and delivery process from the perspective of express freight regional division,smart logistics and the business processes of pick-up & delivery.The perspective of regional division mainly focuses on the fixed customers and the characteristics of the freight being transported have great similarities,the customer's goods can be mixed or require refrigeration or cold chain processing.The perspective of smart logistics lies in the use of advanced information technologies to achieve information sharing,reduce manual operations,and improve customer service levels.The business process perspective is a combination of pick-up and delivery,using popular Petri net modeling optimization techniques to optimize,reduce unnecessary business processes and operational links,improve pick-up & delivery efficiency.At last,based on vehicle path optimization perspective,analysis of the influencing factors of service vehicles,customer service order,express freight weight and volume,the load and volume of the vehicle and other constraints,on the basic of the presupposition,an integrated0-1 integer programming optimization model for pick-up & delivery vehicle routing is established.To solve the model,combining the heuristic algorithm and artificial bee colony algorithm,which is a group of intelligent optimization algorithms,a taboo search-hybrid discrete artificial bee colony algorithm for solving the model is designed.In order to prevent duplicate search of solutions that have been accessed,two corresponding taboo list is introduced,one tabu list is used to store solutions that have been visited,another taboo list isused to store solutions that have not been updated for a limited number of visits.To prevent premature convergence of the algorithm,a roulette reverse selection mechanism is introduced.Then combine the actual situation,select an application example that there are 21 customer nodes to be served and 1 pick-up & delivery service center(railway freight station)in a reference,through MATLAB programming software solving the example,get the best driving route for service vehicles and the order of customers served,gives access to specific service plans for pick-up & delivery vehicles simultaneously.From the results of the solution,the minimum number of vehicles used to pick-up and delivery service is 4 vehicles and the order of customers on each service route cannot be changed,the minimum total travel distance of the vehicle is 169.76 km,this distance is 4.26 km shorter than the shortest distance in the literature.Shows the rationality of the model established in this paper and the effectiveness of the designed algorithm.According to the analysis of the solution results,the maximum load utilization rate can reach 98.33% and the volume utilization rate can reach 81.05% at the beginning of the delivery,after the completion of the pick-up,that is,after each vehicle has served its customers on its own path,the maximum load utilization rate is up to 80.00%,and the maximum capacity utilization rate is up to 98.42%.After a comparative analysis,in the case of pick-up & delivery integrated operations,both the load and the volume of the vehicle have been fully utilized,reduce extra costs due to empty vehicles,save operating costs for pick-up & delivery transportation company.