抄録
Short-range route liners ply between two harbors or make the round of several harbors. In such routes demand stays low and so does profitability. Therefore, some liner routes are given financial support by national or local governments to keep their service on. Operators of liners on the routes of this kind are to make network design to keep operation cost lower, while their customers demand higher convenience in the service. A shuttle service between a mainland and an island harbors raises its convenience to a higher extent. But when a liner operator has more than two destinations in his charge, the shuttle service usually brings about heavier load on his side. Instead of the shuttle service, a network route service calling at several ports shortens the operation time without reducing the number of trips. However, it can cause the customers of the route to detour and it takes them more time to get to their destination. The optimization of operation time for operators and that of traffic time for customers are, so to say, ambivalent factors. In such cases, the decision maker finally chooses a satisfying solution as pareto optima among all feasible service levels. We propose in this paper an operation planning problem with two objectives : one is minimization of operation time (nearly equal to operation cost) and the other that of time required for traffic. This paper also proposes an operation planning method designated to make short range remote island network route without reducing the number of services in consideration of customers' needs. We formulate it as an integer planning problem, and a solution algorithm is proposed. The validity of this operation planning method is shown in this paper.
