取这个圆盘的平面。
他们将世界描绘成一个平面的圆盘，这也显示出巴比伦人认为地球是平的。
They depict4 the world as a flat disc, which shows that the Babylonians thought the earth was flat.
该模型采用三层平面布置的带电圆盘来模拟雷云空间，雷云静电场的计算采用镜像法。
The model simulating thunderstorm cell by means of three layers plane charged disk, the calculations for thundercloud electrostatic field use mirror method.
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