The result shows that their relative errors are within 5%,the daily-arriving-ship quantity is close to Normal distribution,the headway is close to Erlang distribution in inland waterway. 9 tabs,4 figs,9 refs.

• 比较结果表明其相对误差均在5%25以内,说明内河航道日到船艘数服从正态分布,日船头间距近似为爱尔朗分布。