インフラ設備の最適アフターサービス戦略に関する研究(第3報)

エレベータ保全巡回計画問題に対する定式化と解法

抄録

This paper discusses about the maintenance routing problem of the elevators, which are the typical case of the infrastructure equipment. The purpose of this paper is to give the practical formulation and the proper solution to the maintenance routing problem to seek the optimal routing schedule, which minimizes the Cost Of Quality (the loss evaluated in terms of cost, to be incurred when an elevator breaks down), the time for the maintenance team to access the malfunctioning elevator, and the total visiting and working time of each maintenance team. To plan the routing schedule, two indexes are proposed; one is named the "customer satisfaction index" that expresses how well each maintenance team's visiting route can manage the unpredictable failures and the other the "route length index." The problem to be solved is divided into two steps of Generalized Assignment Problem and Traveling Salesman Problem by using these two indexes. Furthermore, Lagrangian Decomposition and Coordination Method and Local Search Method are applied as the solution. From numerical experiments, the characteristics of the proposal method are clarified, and it is shown that this approach can provide a more cost-effective and better routing schedule than the one given by the traditional method.