Modeling And Application Of Inter-ship Traffic Conflict In A Sea Area With Heavy Nearshore Traffic

Maritime transport is the backbone of international trade and the global economy.Over80% of the volume of international trade in goods is carried by sea.Guaranteeing the safety of ship navigation is a necessary condition to support the sustainable development of shipping industry.Hence,ship safety and security which has been the research subject of all time.With the development of ship safety and security technology,the number of water traffic accidents is on a decreasing trend.Hence,the method of analyzing traffic safety in waters through accident data has the problems of small samples and low confidence level.In order to improve the non-adaptability of traditional traffic safety evaluation methods,Traffic Conflict Technology(TCT)has been introduced into the research of waterborne traffic safety due to its advantages of "large samples,rapid,quantitative,and non-accident."Focusing on the relationship between the spatial characteristics of the inter-ship traffic conflict model and the traffic risk in the nearshore area,this thesis carries out the research on the modeling and application of the inter-ship traffic conflict in the nearshore area with heavy traffic.The original AIS trajectory data are tested,modified and interpolated synchronously by using the data preprocessing method.Based on the traditional ship domain model and the water traffic conflict severity model,a multi-risk ship domain model is proposed,and inter-ship traffic conflict model is constructed.At the micro level,the specific traffic conflicts faced by a single ship in a certain time interval are analyzed.At the macro level,taking the waters of Tianjin Port as the research object,the data contained in the five grids with the largest number of inter-ship traffic conflicts in the waters of Tianjin Port are analyzed by using AIS data,the macro intership conflicts in this area are calculated,and their geographical distribution characteristics are analyzed.The experimental results show that the abnormal AIS position data detection and correction method proposed in this thesis can not only delete the duplicate data and missing data,but also identify and correct the abnormal ship sites.Finally,using the data interpolation method,it can fix the sampling frequency of AIS data and lay a data foundation for follow-up research.According to the proposed inter-ship traffic conflict model,the corresponding times of inter-ship traffic conflict in the studied waters can be obtained.it is proved that the inter-ship traffic conflict model proposed in this chapter can effectively identify the severity of the conflict between the ship and the target ship at the micro level.In the analysis of the inter-ship traffic conflicts in the waters of Tianjin Port,it is found that there is a strong correlation between the port channel waters and the number of inter-ship conflicts,and the areas with high inter-ship traffic conflicts are concentrated near the port channel waters with high ship density.The inter-ship traffic conflict model is analyzed from the micro and macro point of view in this thesis,which can effectively help researchers and ship drivers to understand the marine traffic risk from the spatial point of view.It provides a new idea for the study of the spatial dimension of maritime traffic risk.