Study on application of optimization methodology to determine express subway station in the subway operation plan

초록

In railroad transportation system, it has been an interesting subject to develop a plan for an express subway system for a long time because passenger naturally wants to arrive at his or her destination with spending the minimum time cost. In developing the efficient express subway system, train performance firstly must be considered. There are several train types for express subway system. One of them is to operate high performance train (i.e. higher acceleration and deceleration capacity) as local subway and normal train as express subway. It has advantage of giving the less time loss to local subway passengers and the timesaving chance to passengers of express subway at the same time. And in this case, fewer side track is needed which demands the massive construction cost. With the fixed train performance, operation plan can be the main factor to maximize the efficiency of express subway. And there are many constituent elements in operation plan such as headway, number and location of sidetrack, train operation pattern and express train stops, etc. Among them, to determine express train stop is considered as the main strategy for express system because it directly affects the travel time and number of passengers who benefits from express system. Express train stop must be determined in consideration of transfer station, distance between adjacent stops and passenger traffics as well as the whole travel time. So far, in many researches, express train stop was setup uniformly according to some criteria or by empirical method Therefore, reliability of these results might be inadequate. To increase reliability of result, objective analysis should be performed to determine express train stops. In this study, optimization methodology was researched to determine express train stops in the express system with high performance train as local subway. Genetic algorithm was applied as an optimization method. Transfer station, travel distance and passenger traffic were considered with gains in an objective function. From the optimization result, optimal express train stop setup was established.