基于AIS大数据的南京长江大桥水域规律航迹研究

Pattern recognition of ship routes in the Nanjing Yangtze River Bridge area based on AIS big data

南京长江大桥水域通航环境复杂,安全风险高。掌握船舶航行规律,对桥区水运安全监管及航道优化具有重要意义。利用船舶自动识别系统(AIS)大数据,采用自动化并行航迹密度计算方法,识别出不同大小的船舶在不同水期的规律航迹分布,并结合多源数据分析其时空变化特征。通过研究发现大桥水域船舶航行总体符合航行规则;相比小型船舶,大型船舶航行更加规范,通过桥孔时位置更居中,和桥轴法向夹角更小,主航迹带与航道重叠度更高;洪季受水流作用影响,船舶航迹较枯季整体偏北,随水位降低呈逐步向南演变的趋势。

The navigational condition of the Nanjing Yangtze River Bridge is complicated with high safety risk.It is of great significance to master the navigation rules of ships for maritime surveillance and waterway design.Applying a parallel approach developed for calculating the density of ship trajectories in the Nanjing Yangtze River Bridge waters based on AIS big data,we recognize the distribution of the regular routes of ships of different sizes in different seasons,and find that most ships follow the navigation rules of the Nanjing Yangtze River Bridge waters in general.Compared to small ships,large ships are more formal in sailing across the bridge.When passing through the bridge span,the position of large ships is more centered,the angle between the large ships′bow direction and the normal direction of the bridge axis is larger.Meanwhile,the overlap between the lane boundary of the large ships and the designed waterway is much higher than that of small ships.We also find that the ships prefer to take a northerly route in the flood season and a southerly route in the dry season.With the decrease of water level,ship tracks gradually change to the south.