In most cases it is derived from the AC mains by means of a transformer and rectifier.

大多数情况下直流电是从交流电通过变压器和整流器而来的。

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A design method of using GAL to make a constant current source is introduced, proving a new method of current stabilization by means of driving regulated transformer by a controlling device.

主要介绍以可编程门阵列器件构成恒流源核心控制电路的设计思路，通过机电自控装置驱动可调变压器实现新的稳流方法，实验证明这一方法是可行的。

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In this paper, a new scheme to realize O-QAM system by means of cascading a discrete cosine transformer (DCT) and a weighting network is presented.

本文提出用离散余弦变换(DCT)处理器级联一个权重网络实现O - QAM系统的新方案。

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