A port is a critical facility that affects on a nation both socially and economically. Thus, the size of a port and the times of a port development are important factors following by port demand forecasting process in the port planning.
Econometric model has been used to forecast port demand. However, the model doesn't take into account the distance and time between a port and an origin(destination). Also the distribution of production-attraction freights over the region isn't considered on the planning process.
The study develops the model involved above factors through trip distribution model in traditional four step demand forecasting. As a result, the singly-constrained gravity model is applied in order to forecast freights for each item.
The accuracy of the model is high, because MAPE value is less than 10.0% for the most of items. But both coal and steel don't meet the standard.
In this paper, port attractiveness as a new index is utilized to conduct singly-constrained gravity model. Impedance(time or distance) between a port and a region are considered.