Research On Application Of AIS Data In The MSP Of The E-Navigation

With e-navigation strategic is put forward and implement step by step,ships are larger,draught is deeper and the increasing of ship number,the demand of ship navigation safety about Maritime Service Portfolio(MSP)is growing.As a good data source of maritime related research,AIS has achieved remarkable results in the current maritime application research.Based on the idea of "AIS data derived from ship and provide service to ship",we explore the application of AIS data in e navigation’s MSP.Paper first give an overview of the AIS system and related regulations,and then expounds AIS message parsing methods,and researching AIS data quality at the same time by the method of literature research,summarizes the errors existing in the current AIS data types,and putting forward two kinds of AIS data quality control methods,namely the detailed data deletion method and data correction method according to abovementioned error types.What’s more,this paper explores emphatically the application of AIS data in the e-navigation’s MSP4,In order to improve navigation safety and reduce the harm to the marine environment caused by oil spills which caused by the collision and stranding of ships.And specific research application of AIS data in quantitating nearshore channel depth utilization aspects and analyzing urgency of multiship encounters.For the former,propose that using the ratio of draught t to the instantaneous water depth as a quantitative index to quantitatively analyze the utilization rate of water depth.Considering restrictions by tide station number,at the same time the solutions was proposed that filter tidal influence and taking the chart depth instead of actual depth of water,and using the relationship between the ship’s draft and water depth in the study area to selected the ship that did not taking tide,and taking these ships as quantitative evaluation sample.The result show that available space in main channel is greater than the boat channel by taking the Tianjin Port Compounded channel AIS data as the sample between January and March in 2016.So in order to improve t navigation safety,it should be focused on the maintenance of dredging in boat channel.For the latter,concept of urgency is defined,and two geometric factors that the distance which represent the current state between ships and azimuth distribution was proposed as basic indicators in analyzing the urgency of multiship encounters.The distance between ships is calculated based on the Euclidean distance calculation and quantizing it based on information contents.What’s more,making parameterization about bearing distribution based on the international regulations for preventing collisions,namely,dividing the 360 degree azimuth space by using 4 * 72 double layers bearing interval differentiate method,and calculated the proportion that other ships occupies the bearing interval in different layer respectively,the product of above calculated proportion is the parameterization of bearing distribution.And then apply the multiplication rule to synthesis the above two index.It also points out that using the circle ship domain with the radius in 4 times length of target ship as the space boundary constraint conditions.It is proved that this method can be used by theoretical verification and verification of function nature about numerical calculation function,and the expression of urgency map is better than heat map.