A Contribution to Optimum Selection of Fleet Size (I)

Abstract

This paper is concerned with a problem to select an optimum fleet size to serve a transport demand at an arbitrary route with one port loading and one port unloading. The quality of a fleet size is considered to be judged on the transport costs and the service qualities. An optimization problem is set up for determining the optimum fleet size to minimize the weighted sum of the transport costs and the service qualities. Basic mathematical models relating the transport costs and the service qualities to a fleet size, i.e., the number of ships, the pay load and the service speed, are developed for a case of tankers. Tci llustrate the validity of the proposed optimization problem and the mathematical models, an optimum fleet size is determined in an arbitrary selected tanker route, under the assumption that the transport demand is fixed. The effects of the various factors, such as variations in the length of voyage, the mathematical models, etc. on the optimum fleet size are briefly discussed.