Between 1990 and 1998, road haulage increased by 19.4%, while during the same period rail haulage decreased by 43.5%.

在1990年到1998年间，公路运输增加了19.4%，而同期铁路货运量下降了43.5%。

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The optimal parameter selection problem of rail haulage system in.

本文对煤矿井下轨道运输系统参数优化问题进行了讨论。

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