Double-stack container trains are the new railway products which can increase transport capacity with higher speed and lower unit operating cost.

铁路双层集装箱运输是一种运输速度快、运输费用省、单位运营成本低、能使运能提高的铁路货运新产品。

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On the basis of Social Economic Engine Model (SEEM), this paper proposes the utility function of economic unit regarding to the speed of economic increase and surplus first.

在社会经济发动机模型（SEEM）的基础上，提出了经济主体对于经济增长速度和经济剩余的效用函数；

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