Modeling and application of ship density based on ship scale conversion and grid

Abstract

To explore the regularity of ship density and ensure the safety of maritime traffic, a ship density model based on ship scale conversion and grid is established by considering the impact of ship size on traffic safety. A non-parametric kernel density estimation (KDE) method is used to obtain the probability density function of the ship density by selecting the appropriate kernel function and determining the optimal bandwidth. To process and store Automatic Identification System (AIS) data efficiently, a grid-based storage method of AIS data is proposed in this paper, and the relationship between grid width and sampling interval is established. The experiments result proves that the grid-based AIS data storage method saves 64% of storage space compared with the original AIS data. The ship density model based on ship scale conversion can reflect the impact of ship size on the maritime traffic. The distribution regularity of ship density can be obtained through the probability density curve of ship density and statistical characteristics. The research results show that the proposed method can provide theoretical support for the safety supervision of the maritime authority. It can also be recommended for the evaluation of VTS centers in vessel traffic management.