FLEET OPTIMIZATION AND ITS DISTRIBUTION ON THE LINES UNDER CONTAINER FLOWS UNCERTAINTY

Abstract

Introduction. Planning the fleet composition, which corresponds to the goals and competitiveness of the carrier company, as well as modern trends in the container transportation market, is based on the study of container flows, taking into account their uncertainty. This forms the information basis for making decisions regarding the structure of the fleet and its operation. These decisions also involve considering the feasibility of operating liner services in general and assigning vessels to them, in particular. Results. A mathematical model for the strategic management level is proposed, where the period of time under consideration is a year or more. The fleet includes both own and timecharter vessels, so the model variables reflect the relevant conditions – which vessel or vessels operate on a certain line, both own and leased vessels. The target function of the model is the total profit from the operation of vessels, which takes into account, in addition to the profit from the operation of own and leased vessels on the lines, also the profit from own vessels that are proposed to be leased on time-charter, taking into account economic feasibility. The model limitations take into account: ensuring the volume of transportation in the range from pessimistic to optimistic levels between the ports of the lines; the permissible number of vessels leased on time-charter; ensuring a certain level of efficiency of each vessel on the lines. The optimization results provide the fleet composition and distribution of vessels on the lines. Conclusions. The proposed mathematical model for optimizing the fleet composition and its distribution on the lines is reliable, taking into account the compliance of the results with the input data and the adequate response of the results to changes in the input data. This model, as a development of existing models, does not contradict the results of previous studies that created an appropriate theoretical basis for the specified development, which also confirms its reliability. The optimization results form a basis for decision-making, allowing for “what-if” experiments with the level of freight rates, operational costs of vessels, work volumes, the cost of time charter, etc.