基于AIS数据的船舶锚位面积计算

Calculation of ship anchor berth area based on AIS data

针对锚泊船舶实际占用水域面积的快速计算和分析问题,提出一种基于船舶自动识别系统(automatic identification system,AIS)数据的船舶锚位面积计算方法.首先,对AIS轨迹数据进行集成、清洗、分段等预处理,提高数据质量;其次,使用一种基于密度的停留点识别算法识别船舶锚泊点,提取船舶锚位信息;再次,使用单调链凸包算法从船舶锚泊点中提取船舶锚位边界;最后,分别使用鞋带定理和多边形形心公式完成对锚位面积和落锚点概位的求取.实验结果表明,利用该方法得到船舶锚位面积是可行的.

Aiming at the problem of rapid calculation and analysis of the water area actually occupied by anchored ships,a calculation method of ship anchor berth area based on the automatic identification system(AIS)data was proposed.Firstly,the AIS trajectory data was pre-processed with integration,cleaning and segmentation to improve the data quality.Secondly,a density-based stay point identification algorithm was used to identify the anchor points and extract the information of the ship anchor berth.Thirdly,the monotone chain convex hull algorithm was used to extract the anchor berth boundary from the ship anchor points.Finally,the shoelace theorem and the centroid formula for a polygon were used to obtain the ship anchor berth area and the approximate position of the dropped anchor,respectively.Experimental results show that it is feasible to obtain the area of anchor berths by using this method.