[4] Scheepens R, Willems N, Van de Wetering H et al. Interactive visualization of mulvariate trajectory data with density maps[report]. IEEE Pacific Visualization Symposium, PacificVis 2011. Hong Kong, China, 147-154(2011).
[12] Montewka J, Krata P, Kujala P et al. A model for risk analysis of oil tankers[J]. The Archives of Transport, 12, 423-445(2010).
[29] Li W F, Mei B, Shi G Y. Automatic recognition of marine traffic flow regions based on kernel density estimation[J]. Journal of Marine Science and Technology, 26, 84-91(2018).