Optimization Model And Method Of Urban Railway Transit Vehicle Use Planning With Long And Short Routing

As one of the most basic transport planning, urban railway transit vehicle use planning has important influence on operating costs and transportation service quality. However, the domestic and international study on this subject is still on the groping stage. There is not any mature model and algorithm, as well as any computer systems. Therefore, it is urgent demand to find practical and effective mathematical models and solving method, and automatically scheduling urban railway transit vehicle use planning by computers.Based on the development reality of urban railway transit and the advanced experience at home and abroad, this paper take a series of related research on optimization model and method of urban railway transit vehicle use planning. The main works accomplished in the paper include:1. Expounds the definition of urban railway transit vehicle use planning, summarize the principles and classification. Discusses the application modes of long and short routing. Then conduct a comprehensive study of long and short routing: the different percentage of long and short routings, the influence of different turn-back modes on turn-back capacity; Calculate the time interval between departure trains.2. Analyses the features of urban railway transit vehicle use problem. Based on the results of the analysis, points out the defects of traditional Assignment Model:the traditional assignment model cannot avoid the problem of nesting turn-back vehicles, and cannot dynamic report the number of vehicles on routes, and also cannot balance the use of each vehicle. The improved assignment model——Rolling Time and Space Assignment Model is discussed against this problem to solve the urban railway transit vehicle use problem. The main idea of the Rolling Time and Space Assignment Model is to divide a whole day’s operation time into different time intervals based on the density of train paths. Dynamically adding and deleting vehicles which entrance/exist from the depot, and rolling time and space method to assign vehicles to undertake the train paths tasks.3. Constraints and objective functions of urban railway transit vehicle use problem were discussed in detail in this paper.Then establish the Rolling Time and Space Assignment Model. It is allowed to tune a short time△t when considering the connecting time constraint which will increase the flexibility of the use of urban railway transit vehicle. After that, solve the urban railway transit vehicle use problem with the Rolling Time and Space Assignment Model, and puts forward the algorithm of the problem. The Hungary algorithm is used to solve the model.4. This paper explored the method and algorithm steps of the Urban Railway Transit Vehicle Use Problem with Long and Short Routing deeply. The problem is divide into two stages:making sub-routings and then building routings based on the sub-routings. On the first stage, apply the Rolling Time and Space Assignment Model and solve it with the Hungary algorithm by MATLAB programming. On the second stage, heuristic search of path-exchange strategy were designed to optimize the routings in terms of effectiveness and balance.5. An example of Shenzhen Metro Line8was presented to show the feasibility of the proposed model and algorithm. And gives out suggestions of urban railway transit vehicle use planning based on the results.