The natural frequency of the gas column in simple pipelines was solved using the finite element analysis method. The result agreed with that derived with transportation matrix method.

采用有限元分析方法，对简单管道气柱的固有频率进行求解，其结果与用传递矩阵法求得的结果是一致的。

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The OD matrix then has reflected in the specific time interval along with the time variation transportation demand pattern.

OD矩阵则反映了特定的时段内随时间变化的交通需求模式。

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Traffic assignment is that the od matrix is loaded onto the transportation network under some assignment models.

交通分配是将各交通分析区域间的出行交换量，按照一定的模型方法分配到各条具体路段上。

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