Research On Optimized Establishment Method And Evaluation Method For Train Operation Plan Based On Alternative Graph Theory

As the command center of daily transportation organization work, railway traffic dispatching directs transportation production work on behalf of the leaders at all levels respectively. It takes the responsibility for ensuring transportation safety and efficiency, coordinating passenger traffic load and freight traffic load, guaranteeing national key transportation, promoting service quality and so on. All levels’dispatching plans are the regulation and basis for railway transportation enterprise to carry out dispatching work.This dissertation proposes the concept of train operation plan based on characteristics of all levels’dispatching plans and their environment requirements in existing railway system. Taking train diagram, daily shift traffic plan, future transportation task arrangments and external expectations as foundation, using previous real plan’s feedback information and dispatchers’ personal experience as reference, train operation plan is defined as train running regulations during a period time in governed sections which makes full use of available transportation resources under the limitation of actual train operation states and other restraint conditions. Train operation plan is an important component of train traffic control automation and has the fundamental and decisive function for giving full play to the resource capacity of railway transportation and ensuring railway operation safety.After consulting a large number of related literature at home and abroad, this dissertation designs an optimized establishment method and an evaluation method for train operation plan and proposes an optimized establishment model integrated with such methods, being in accordance with the organization mode of railway transportation in China.Firstly, based on analyzing the basic characteristics and optimization requirements of train operation plan, the research1) uses the divide and conquer strategy to establish and optimize plans hierarchically under different optimization objectives;2) maps various train dispatching resources to elements in alternative graph model;3) constructs plan’s establishment and optimization model based on alternative graph theory by the way of parameter definition, parameter correlation, data structure optimization, restraint condition description and so on;4) employs initial plan establishment algorithm, MSOBB algorithm and ICFPSO algorithm to solve the model respectively and gain initial plan, feasible plan and optimized plan correspondingly. The introduction of Simulated Annealing algorithm could guarantee the convergence property of initial plan establishment algorithm; Train priority affects the algorithm flow direction in MSOBB algorithm during resource allocation, branch and search operations in BB algorithm and optimization objective calculation; In ICFPSO algorithm, membership grade under fuzzy concept increases particle impact range, convergence factor related to iteration speeds up convergence process, mutation particles in escaping mechanism enlarge search scope,2parameters of virtual train and buffer time slot extend plan’s robustness. Through a combination of these3algorithms, the train operation plan’s establishment and optimization integration program is developed.Secondly, general construction principles for comprehensive evaluation framework of train operation plan are given out by the analysis of current dispatching situation, implementation environment of plans’ from different levels and evaluation problem itself. Comprehensive evaluation framework of train operation plan is built up according to the principles by combining the subjective expert evaluation method and objective ISM method. On this basis, to solve the problems such as oversimplification in current evaluation process, lack of fuzzy measurement in expert judgment and difficulty in consistent adjustment of AHP method, the dissertation uses AHP method in multiple attribute decision making area to determine the weights of evaluation indexes and puts forward an improved AHP method based on Vague Set for train operation plan’s evaluation research.Finally, referring to model predictive control theory, optimized establishment model for train operation plan based on comprehensive evaluation method is developed and logic relationship among the influencing factors in train dispatching process, influence degree for such factors, solving measures and coping methods in model is established. At the same time, the main functions and improvement suggestions for key modules in this model are described.