Modeling and Its Analysis on the Gross Cargo Throughput

Aiming to describe the developing trends of the gross cargo throughput, a model of describing the distribution of cargo throughput is proposed. The gross cargo throughput was direct related to the number of cargo ships arriving at the port and the operating efficiency of handling equipment. A compound variable, being composed of the number of cargo ships arriving at the port and the operating efficiency of handling equipment, is constructed. The gross cargo throughput is the sum of all compound variables which indicated the cargo throughput each time when cargo ships arrived at the port. Probability distribution of cargo throughput was acquired using wald equation. It shows that the distribution of the gross cargo throughput depended on the probability distribution of the number of cargo ships arriving at the port. The model can overcome previous shortcomings: the previous ones can not describe the probability of the specific value of gross cargo throughput in future properly. Meanwhile, the distribution model of cargo throughput was proposed depending on the relationship between the number of cargo ships arriving at the port and the operational capability of handling equipment in the port. At the same time, some factors which affect the gross cargo throughput are analyzed. In order to testify the efficiency of the model, the cargo volume of a port in Shandong province was taken as an example. Case study shows that actual results coincide with theoretical analysis.