为分析航道中船舶间时距概率分布特性,利用大量的船舶AIS数据求得船舶间时距;通过数理统计分析,结合γ分布函数特性,建立船舶间时距分布模型,并讨论模型的几种特殊情况。根据2012年10月厦门港主航道船舶AIS数据,利用矩法对模型参数进行无偏估计,使用gAuSS-lEgEndrE求积公式求解其概率分布。通过卡方检验,求证厦门港主航道船舶间时距概率分布服从γ函数分布,并分析其概率分布特性。研究表明,γ分布函数对船舶间时距的变化具有较强的适应性。The time-interval between ships defined as the time difference of two ships to cross a given observation line is one of the safety parameters for ships navigating in succession.To determine the probability distribution model,which approximately takes the form of γ-function,of the time-interval between consecutive ships through statistic analysis of the AIS data and discusses the special cases of the distribution.The time-interval distribution in Xiamen port is studied.The unbiased parameter estimates of the traffic model are determined according to the AIS data of Oct,2012 in Xiamen Port by the moment method,and the distribution of the time interval is obtained by Gauss-Legendre quadrature formula.The Chisquare test validates that the density distribution of time-interval between ships in Xiamen port is subject to a gamma distribution,proving the adaptability of gamma distribution for describing time-interval between ships
