Identification and measurement of seaward accessibility of port based on shipping networks
The efficient accessibility of port infrastructure is a determining factor in international transportation costs and a prerequisite for regional connectivity,interconnectivity and interaction.Therefore,it is a challenging and crucial research topic in the study of maritime shipping networks,to determine the seaward accessibility of port and reveal the patterns of interaction and interconnection between ports.Taking the shipping network of major ports along the Maritime Silk Road between China and the rest of the world as the research object,based on the theory of land accessibility,under the consideration of the frequency of liner service and the influence of geographic factors,we propose a seaward accessibility model of ports incorporating weighted paths,and improve the centrality indicators of complex networks.And the sample processing for the two years of 2008 and 2018 was unified,so as to make the relevant indicators more comparable,and to validate their validity and applicability.The results indicate the following:(1)On the whole,considering the liner service frequency as an influencing factor,the actual functional differences of ports reflected by each centrality index are revealed at a deeper level.From the results of kernel density analysis,there are significant absolute differences and differentiation in the efficiency of route operation(weighted closeness centrality)and the port regulatory capacity(weighted betweenness centrality)of the maritime shipping network,and the"polarization"phenomenon of port accessibility is still obvious.(2)The statistical characteristics of weighted composite centrality suggest that individual dominant functions of ports may deviate in reflecting their influence,and the combination with weighted composite centrality can provide targeted suggestions for optimizing the functions that ports need to embed in the"shipping network".(3)The port maritime accessibility measured by the weighted average shortest path demonstrates a weak discretization phenomenon with a long right tail,and the"Matthew effect"is more pronounced.Only a few ports show significant improvements in accessibility,while ports with low accessibility are expected to persist in the long term,and the absolute difference between different ports increases.
万方数据
维普
