Optimization Methods On The Connection Plan Of Rolling Stocks For Urban Rail Transit Considering Utilization Equilibrium

As an important basis to complete the transportation task of urban rail transit,rolling stock utilization plan is of great significance to coordinate the operating cost of enterprises and the service level of passengers.As the rolling stock shall be repaired in time when it reaches the maintenance standard,long-term utilization plans also need to take into account the maintenance plan of rolling stocks,In view of this,the meaning of rolling stock utilization plan in this dissertation is a comprehensive plan considering maintenance factor.In addition,the unbalanced utilization will lead to uneven wear of rolling stocks,which will affect service life.In this context,how to arrange rolling stocks to undertake the transportation task while reducing the operating cost and ensuring equilibrium utilization is an urgent problem to be solved.Starting from this practical problem,this dissertation focus on the optimization of rolling stock utilization plan.The main contents are as follows:(1)This dissertation expounded the basic concept and influencing factors of the connection plan of rolling stocks,and clarified the optimization strategy of this optimization problem.On the basis of the optimization definition of rolling stock utilization plan,the influence of several factors on rolling stock utilization efficiency is analyzed.Based on the existing utilization method,a two-stage solution strategy is developed,namely,the one-day rolling stock utilization plan in the first stage and the long-term rolling stock utilization plan in the second stage.(2)In the first stage,the one-day rolling stocks utilization plan model of urban rail transit is constructed without considering the maintenance plan.Through the analysis of the graphic elements and the basic task of the connection plan,convert train operation diagram into node connection network diagram.The model of one-day rolling stocks connection plan is established,which aims at the lowest continuous waiting cost and fixed use cost,and the greedy algorithm is designed.The CPLEX and the greedy algorithm are respectively used for example verification,which proves the correctness of the model and the superiority of the greedy algorithm.(3)In the second stage,the long-term rolling stocks utilization plan model of urban rail transit considering the maintenance is constructed.Taking the daily utilization plan obtained from the first stage model as input,the network diagram was constructed to coordinate the rolling stocks connection and maintenance plan under the space-time constraints.A dual-objective programming model was established to minimize the fixed use cost and the imbalance of mileage under the vehicle,and a parallel Tabu search algorithm was designed to solve the problem.The Pareto optimal solution was introduced to solve the dual-objective optimization problem.(4)An empirical study based on a rail transit line.Firstly,the first stage model is used to solve the rolling stock utilization plan in a single day.Based on the data input and maintenance procedures,the second-stage model is used to solve the long-term rolling stock utilization plan.According to the Pareto optimal solution,a number of long-term rolling stock utilization plans were solved,and a number of indicators were designed for analysis and comparison,and three feasible plans with different applicable conditions were selected,which verified the rationality of this dissertation’s method.Finally,some optimization experience is given,which has a certain guiding significance to urban rail transit operation.