Research On The Measurement Of Heterogeneity Of Area-Wide Vessel Traffic Flow Based On AIS Data

As one of the complex system,maritime transportation has the mechanism characteristics of multi-agent subject,multi-factor coupling and multi-objective collaboration etc.Among them,the characteristics and evolution of vessel traffic flow is one of the essential influencing factors which directly affect the safety and efficiency of marine transportation.With the heavier maritime transportation,the moving situation of area-wide vessel traffic flow is becoming more complicated and varied,showing the characteristics complex structure,crisscrossing,higher density and wider range.In which,the spatial and temporal distribution of vessel traffic flow is the embodiment feature for perceiving the characteristics of vessel traffic flow.The definitions and related analysis methods of traditional vessel traffic flow moving situation indicators are mostly described from dynamic characteristics,lacking research on the morphologies and spatial-temporal characteristics of vessel traffic flow which inevitably causes ineffective and incomprehensive supervision of vessel traffic flow.Therefore,it is vital to carry out the research on area-wide morphologies characteristics based on AIS data and combined with data mining,mathematical analysis,complex systems,and advanced theoretical techniques in the fields of roads,air transportation.Through analysis the morphological characteristics,influencing factors as well as the spatial-temporal trajectories of vessel traffic flow,using discrepancy of point sets,proposed the measurement model of vessel traffic flow spatial heterogeneity.Meanwhile,DTW algorithm,K-Means clustering and skeleton extraction methods are applied for establishing the measurement model of area-wide vessel traffic flow spatial-temporal heterogeneity.Finally,case studies are used to verify the reliability and effectiveness of the measurement model.The specific researches are done as follows:(1)Qualitative analysis of area-wide vessel traffic flow spatial heterogeneity.According to the basic concept and spatial distribution characteristics of vessel traffic flow,comprehensively analyzed the characteristics and influencing factors of vessel traffic flow,proposing area-wide spatial heterogeneity.Qualitative analyze the basic concepts,influencing factors and evolutionary mechanisms of area-wide vessel traffic flow spatial heterogeneity.(2)Area-wide vessel traffic flow spatial heterogeneity measurement model.According to the qualitative analysis of spatial heterogeneity,using the deviation accurate calculation formula of point sets,establishing area-wide vessel traffic flow spatial heterogeneity measurement model based on the historical statistical AIS data.(3)Qualitative analysis of area-wide vessel traffic flow spatial-temporal heterogeneity.According to the characteristics of spatial-temporal trajectory of ship traffic flow,proposed the concept and qualitative analyzed the characteristic of area-wide spatial-temporal heterogeneity.(4)Area-wide vessel traffic flow spatial-temporal heterogeneity measurement model.Based on the qualitative analysis,using DTW algorithm,K-Means clustering,skeleton extraction,proposing area-wide vessel traffic flow spatial-temporal heterogeneity measurement model.(5)Case analysis,the area-wide vessel traffic flow spatial heterogeneity and spatial-temporal heterogeneity measurement models are analyzed by using the AIS data of the main channel of the Yangtze river,Yantai West Port area and the Port area of Qinhuangdao.The measurement results are statistically analyzed and compared,and the eigenvalues are described in detail to verify the feasibility and effectiveness of the model.This research results propose the area-wide vessel traffic flow spatial heterogeneity and spatial-temporal heterogeneity measurement model,enriching the theoretical method for morphological characteristics and moving situation of area-wide vessel.It is an effective supplement to the research and moving situation of area-wide vessel traffic flow,which has vital theoretical and practical significance for the formation of the complete theory for area-wide vessel traffic flow.