摘要：The “boundary line analysis method” calculates the minimal total annual operational costs used for the optimisation of number of tractors owned by agricultural companies. This calculation reflects the actual need of tractors used in the selected time periods during a year. The above method is based on data gained during five day periods (so-called pentads) in the plant production Farm Estate Lány which belongs to the Czech University of Life Sciences Prague. Based on the annual use of tractors in the company, operational costs involve tractors owned and hired. The calculated curve changes in relation to the total annual costs for the owned tractors. The economically optimal number of the owned tractors would be reached at the minimum point where the total annual costs curve is low whilst all working operations in the company have been done. Due to the use of tractors during the pentads, it is recommended to own exactly the number of tractor-machine sets given by the calculated minimum. For all the other works, it is advisable to use hired tractors, operationally leased tractors or outsourced services.
关键词：costs optimisation; tractors deployment; tractor number optimisation
