Alternating current is different from direct current in that it constantly changes its direct of flow.

交流电与直流电的不同之处在于交流电不断地改变其电流流动方向。

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The direct current method is a simple and convenient method for calculating power system load flow which is applicable for on line control and calculation by computer.

网流直流法是适用于计算机在线控制和计算的一种简便潮流计算法。

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S series Linear Shaft Motor is a brushless direct drive tubular linear servomotor consisting of just a magnetic shaft and a moving coil assembly (forcer) which is controlled by the flow of current.

系列的线性轴电机是一款无刷的，直驱动伺服电机，由磁轴和运动线圈组成，运动线圈控制电流量。

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Direct current, in which electrons flow in only one direction, worked fine over short distances but was problematic for the long haul.

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