The Structural Characteristics Of The World Shipping Network And Its Dynamics Behavior

The global maritime shipping system is a typical complex system,it is composed by hundreds ports and thousands ships,the quantities of ports and ships are evolving with time,the relationships among them differ largely in spatial,so there exist many difficulties in researching this system in holism.Nowadays the methodology of exploring global shipping system still adopting reductive ideology,partitioning it to some subsystems for researching,some useful results have been concluded,but these results lose some integral information of system.Network is a mathematical abstract to real system,it characterizing the interactions among system elements,so it is a very useful holistic approach for researching complex system.Based on it,this dissertation regards the ports as nodes and regards the cargo flow among ports as interactive edges from complex network view,so the global maritime shipping system is characterized by a complex network topology graph-global shipping network,this graph directly embodies the complex interactions among ports of global maritime shipping system.In this dissertation,the global maritime shipping system is studied using complex network theory,combining the statistical with comparative analysis methods,quantitative with qualitative analysis methods.The research work was carried out following the route from constructing global shipping network to analyzing structure properties,then exploring the evolving mechanism of this particular structure,finally,discussing whatever dynamical behavior emerged from this network structure.Specifically,this dissertation exploring global shipping network from these aspects:1)Based on consecutive observation and investigation,this dissertation constructs a directed and weighted global shipping network which embedded in a spatial lattice.Then we study a set of measurements of unweighted and weighted global shipping network and attain distributing properties of some typical parameters,for example,we find the average path length of this network is so small but the cluster coefficient is very large,the degree and strength distribution following power-law.Moreover we also explore the correlation between these measurement,the results indicate that the global shipping network containing weighted as well as spatial property.2)The structure of system determines the function and behavior of system,the next question is why the global shipping network presents such structure? Combining the long-term investigating the evolution laws of global maritime shipping system with the statistical results attained from above,we research the evolving mechanism of the global shipping network in detail,construct a traffic driven network model and a geographical constraints network model,all the two model can reproduce some structure properties of global shipping network.3)Community is a conception using in sociology,meanwhile it associating with spread dynamics of system,so it becomes a hot topic.We can find the closeness trading between different countries and traffic distribution among network throng communities, we give the specific definition and partition criteria of community in global shipping network,moreover we introduce a concrete algorithm to find community in global shipping network,and obtain the best partition,at the same time,we shed light on the reasons leading to this partition.4)The global shipping network is a typical infrastructure network,people give much attention to its efficiency and safety,especially,focus on robustness of system when encountered accidental events(such as war,terrorist attack and perturbation of atrocious environment).On the other hand,the dynamical behavior of system must reflect the structure of system,so the last part of dissertation discusses the dynamical behavior of global shipping network,using it we can validate the accuracy of system structure obtained from our results.Through exploring the structure properties and dynamical behavior of global shipping network,we can understand the trading relationship among different countries macroscopically and provide proofs of analyzing local economic relations.Secondly,we can provide theoretical consult for constructing new line,distributing line fairly, improving system efficiency.Thirdly,we can provide theoretical support of designing new port.