Study On Characteristics And Evolution Models Of Vessel Traffic Flow For Complex Navigation System

Regional diversity of global resource distribution and demand generates a strong driving force for international trade.As an important tool in the international trade,the number of vessels is steadily increasing with the growthing demand of global freight transportation.At the same time,with the development of shipbuilding technology,specialization,high speed,enlargement,and intelligence of vessels are becoming an obvious trend,which makes the vessel traffic presenting features of intensive distribution,diversified types,large scales,high speed and so on.Moreover,the complexity of vessel traffic is simutaniously increased.It not only increases traffic density at sea,but also the traffic risk,which puts forward higher requirements for the management efficiency of vessel transportation service.Comprehensive and systematic analysis of characteristics and evolution of vessel traffic flow is a crucial basis to enhance the efficiency of service management of water transportation.This dissertation is focusing on the complex navigation system,the characteristics of vessel traffic flow,the influence factors of the traffic flow,and its evolution mechanism and model of vessel traffic flow.The purpose of the study is to form a system characteristics model of vessel traffic flow and a relation model,researching factors influencing vessel traffic flow and their coupling mechanism.Then,the regularities of vessel traffic flow are revealed and vessel traffic flow evolution model is established to reveal the evolution law of vessel traffic flow.The specific research content includes:(1)The properties,composition elements and their relationship,complexity,and brittleness of the navigation system are analyzed.Service ability of complex navigation system is put forward to simulate the evolution of the system.(2)Based on the concept of vessel traffic flow,vessel traffic flow characteristic model is established using AND-OR diagram.Mathematical models are provided by vectors and sets describing the characteristics of vessel traffic flow and their relationship.Then,the ship data of Tianjin port are analyzed as an illustration to validate the models.(3)On the basis of the analysis of influence factors and their correlation,a hierarchical structure model of vessel traffic flow is established based on interpretative structure model.Then,a coupling model of the influence factors of vessel traffic flow is propose based on graph theory.Finally,the container ship data of Tianjin port are analyzed as an example to validate the coupling model.(4)The evolution mechanism of vessel traffic flow is analyzed according to the aspects of structure and behavior characteristics.Based on complex navigation system,a multi scale evolution prediction model is proposed by using the sparse and low-rank matrices considering the characteristic model of vessel traffic flow;a dynamic evolution model of vessel traffic flow is constructed by using system dynamics theory;a simulation method of vessel traffic flow based on rule constraint is designed considering the micro behavior of vessel traffic flow.Finally,the three models are validated and analyzed by using the data of Tianjin port.In this thesis,evolution of vessel traffic flow is studied based on complex navigation system,vessel traffic flow characteristics,influence factors,and evolution mechanism,enriching the theory and technology of vessel traffic flow.Example analysis results of vessel traffic flow indicate that:the proposed models and methods are in good fitness with the actual data,the vessel traffic flow characteristic model can represent the traffic flow more comprehensively and systematically,the vessel traffic flow coupling model can show the coupling relationship between the elements more accurately,the multi scale evolution prediction model can reflect the more evolution information of the traffic flow,the dynamic evolution model can take into account the co-evolution mechanism of the traffic flow and navigation system,the simulation method can reveal the evolution mechanism of the traffic flow in navigation system in essence.The research results have significant value for the development of port planning and construction,supervision and service measures.