Research On The Disruption Management For VRPSDP With The Change Of Customer Demand And Time Window

Logistics distribution is an important business of the logistics system.As a service link directly to customers,its status is very important.With the rapid development of The Times,people's pace of life faster and faster,the uncertainty of logistics distribution is becoming higher and higher.The changes in customer demand and time window studied in this paper occur from time to time,which may result in the failure to accept the services of logistics distribution enterprises within the agreed time window.Therefore,relevant researchers and enterprise staff are constantly looking for ways to deal with changes in customer demand and time window to minimize the impact of these disturbance factors on the overall logistics system.Disruption management is a methodology to rapidly deal with uncertain incidents.It aims at minimizing the disturbance degree on original distribution system made by randomly occurring uncertain incidents to the original logistics distribution system.Based on the theory of disruption management,this paper carries out a research focusing on the Vehicle Routing Problem with Simultaneously and Pickup(VRPSDP)with the change of customer demand and time window.The main content is divided into the following parts:(1)This paper makes a judgment whether the changes have caused influence to current logistics service plan.The mathematical formula is used to describe the conditions for generating interference from two aspects:demand and time window changes.The disturbance degree of demand and time window changes is clarified from the two aspects of cost deviation and time deviation.The degree of disturbance of demand and time window changes is explained from two aspects of logistics cost deviation and time deviation.The reasonable disturbance measurement is carried out respectively,which provides the quantitative analysis basis for the vehicle scheduling decision of customer demand and time window changes.(2)Based on the above-mentioned disturbance measurement,the concept of generalized total cost deviation is proposed.Aiming at minimizing the generalized total cost deviation caused by uncertain events to the original logistics service plan,a mathematical model of disruption management of is established.A good initial logistics service plan is obtained by designing heuristic optimization algorithm.According to the established disruption management model,the optimization algorithm process based on tabu search was developed to deal with the interference problems caused by the change of customers' demand and time window scientifically and effectively,and obtain the improved logistics service plan.(3)Using the data from six randomly selected Solomon standard test libraries to verify the validity of the model and algorithm,and compare the results with the results of new distribution vehicles and global rescheduling methods.The advantages of the interference management method in this paper are illustrated.In addition,the sensitivity analysis of the relevant parameters in the disruption management model is carried out.The analysis results show that the general applicability of the mathematical model established in this paper can be applied to different logistics distribution enterprises.The proposed disruption model and heuristic optimization algorithm consider the disruption's impact on two aspects comprehensively,which are logistics cost and service time.They can reduce the disturbance caused by uncertain incidents effectively and ensure the service quality.This paper provides some decisions making support on responding customers'demand and time window changes in the process of distribution for logistics companies.