Research On Optimal Utilization Model And Algorithm Of Urban Rail Transit Rolling Stock

In recent years,China has been the country where urban rail transit develops most rapidly in the world.On the one hand,with the increasing number of urban rail transit lines,the demand for urban rail transit rolling stocks is becoming larger.On the other hand,in order to meet the travel needs of passengers,the operation companies make more flexible train operation plans.Therefore,making reasonable rolling stock scheduling plan and improving the efficiency of rolling stock utilization is not only the key part to optimize the allocation of transportation resources,but also an important content to improve the service level of passengers.Take this as the breakthrough point and based on a series of related research at home and abroad,this paper explores the optimal utilization problem of urban rail transit rolling stocks.The main works accomplished in the paper include:(1)Theoretical research on optimal utilization problem of urban rail transit rolling stocks.Based on fully understanding of urban rail transit rolling stocks utilization planning,the paper analyses the influence factors of rolling stocks utilization efficiency from many aspects like train operation routes,train stopping plan,train turn-back mode,station tracks,rolling stock maintenance operation.And the principles for making urban rail transit rolling stocks utilization plan are summarized.This part lays the foundation for establishment of model on the urban rail transit rolling stocks optimal utilization problem.(2)Formulating the optimal utilization model for urban rail transit rolling stocks.The utilization problem of urban rail transit rolling stocks is transferred into Multiple-Depot Vehicle Routing Problem.Taking the constraints of rolling stocks connection and rolling stocks maintenance into consideration,the paper formulates an optimal utilization model for urban rail transit rolling stocks.The objective of the model is to minimize the number of rolling stocks and the number of maintenance times.In addition,a small scale example is designed and solved by ILOG CPLEX.The computation results verify the correctness of the proposed model.(3)The design and implementation of the algorithm.The algorithm is designed based on the max-min ant colony algorithm.Then the process of the algorithm is described in detail,including the construction of the feasible solution,the design of the main algorithm,the initialization process,the internal circulation process and the external circulation process.Finally,the ILOG CPLEX and the proposed algorithm are used to solve cases of different scales respectively,and the calculation results verify the efficiency of the algorithm.(4)Case study and result analysis.Taking the Beijing Subway Line 5 and line 2 as examples,through the test of the linear line and the loop line,the rolling stocks utilization plans of two cases are solved by the algorithm.We contrastively analyze the results without considering the constraint of rolling stocks maintenance and considering the constraint of rolling stocks maintenance.The calculation results show that the proposed model and algorithm in this paper can obtain a better solution in acceptable time when solving practical problems,which proves the practicability of the model and algorithm.