Liu Zhao, Liu Jingxian, Li Huanhuan, Li Zongzhi, Tan Zhirong, Liu Ryan Wen, Liu Yi
Hubei Key Laboratory of Inland Shipping Technology, School of Navigation, Wuhan University of Technology, Wuhan, China.
National Engineering Research Center for Water Transport Safety, Wuhan, China.
PLoS One. 2017 Apr 17;12(4):e0175840. doi: 10.1371/journal.pone.0175840. eCollection 2017.
Understanding the characteristics of vessel traffic flow is crucial in maintaining navigation safety, efficiency, and overall waterway transportation management. Factors influencing vessel traffic flow possess diverse features such as hierarchy, uncertainty, nonlinearity, complexity, and interdependency. To reveal the impact mechanism of the factors influencing vessel traffic flow, a hierarchical model and a coupling model are proposed in this study based on the interpretative structural modeling method. The hierarchical model explains the hierarchies and relationships of the factors using a graph. The coupling model provides a quantitative method that explores interaction effects of factors using a coupling coefficient. The coupling coefficient is obtained by determining the quantitative indicators of the factors and their weights. Thereafter, the data obtained from Port of Tianjin is used to verify the proposed coupling model. The results show that the hierarchical model of the factors influencing vessel traffic flow can explain the level, structure, and interaction effect of the factors; the coupling model is efficient in analyzing factors influencing traffic volumes. The proposed method can be used for analyzing increases in vessel traffic flow in waterway transportation system.
了解船舶交通流特征对于维护航行安全、效率以及整体水路运输管理至关重要。影响船舶交通流的因素具有层次结构、不确定性、非线性、复杂性和相互依赖性等多种特征。为揭示影响船舶交通流因素的作用机制，本研究基于解释结构模型法提出了层次模型和耦合模型。层次模型用图形解释因素的层次结构和关系。耦合模型提供了一种定量方法，利用耦合系数探索因素的相互作用效应。耦合系数通过确定因素的定量指标及其权重获得。此后，利用天津港的数据对所提出的耦合模型进行验证。结果表明，影响船舶交通流因素的层次模型能够解释因素的层次、结构和相互作用效应；耦合模型在分析影响交通量的因素方面是有效的。所提出的方法可用于分析水路运输系统中船舶交通流的增加情况。
