Modelling Research Of Ship Domains In The Typical Inland Waters

With the increase of traffic volume and cargo handling capacity in the Yangtze River,the inland water transport represented by the Yangtze River is developing rapidly,followed by the increase of the ship's number,tonnage and speed,which makes the risk of navigation of the inland waterway increased gradually.So it is need to manage and control the inland waterway traffic more scientifically.It is a good way to build a scientific and reasonable ship domain model.In order to obtain the ship domain model of inland typical water,the AIS data were used to establish the statistical model.By gridding the waters around the target vessel and calculating the occupied grids of the nearest ship around the target ship at each moment,the grid distribution of the ship at each time is superimposed to obtain the grid density map of the single vessel,then the grid density map of the particular type of ship is obtainend.By utilizing the grid density map and the grid density data,the shape and size of the ship domain are obtained.The target ship is classified according to the three factors influencing the ship's field,and the relationship between the ship field and the three kinds of influencing factors is analyzed respectively,then the ship domain model of inland typical waters is constructed.The results of this paper are as follows:(1)The impact of the ship size on the ship domainThe length and width of the ship domain are directly proportional to the length and width of the ship.The ratio between the domain's length,width,area and ship's length,width,area are all gradually decrease with the ship size increases.The same kind of ship domain' size in the dry season is slightly larger than the size of the ship domain of other months.(2)The impact of ship speed on the ship domainThe length of the ship is proportional to the speed of the ship,and the ratio between the domain area and the ship area and the width of the ship are inversely proportional to the speed of the ship.Compared to the center of the ship,the center of the domain is offset.These characteristics are related to the difference in behavior of the inland water ships at different speeds.(3)The impact of the bridge area waters on the ship domainThere are significant differences between the characteristics of the ship domain in the different bridge areas waters in same month and the same bridge area water in different month.These characteristics are related to the bridge hole setting and the water level difference of each bridge under different seasons.The results show that the domain's characteristics of the ships navigated in the inland typical waters all have a big difference with the characteristics of the ship domain obtained in the form of the traditional theoretical analysis and the sea water,the results has a certain reference value for the ship collision avoidance and the water traffic management in the inland water.