但是，如果目标是精确的重放声音的话，一个扬声器必须是声学上的点声源(单极点，全向响应)，或者是一个声学上小的双向源(偶极)。
But if the goal is to reproduce sounds accurately, then a speaker must be either an acoustic point source (monopole, omni-directional) or an acoustically small bi-directional source (dipole).
中央的假设是不列在项目分配的极点，和南北两极的性质是混合的，然后我会计划不说是或没有衣服。
The central hypothesis is not listed in the project distribution poles, and the nature of the north and south poles were mixed, then I will plan not to say yes or no clothes.
然后以重心为极点，对边缘点极坐标化，形成幅角-极径曲线，在该曲线上寻找局部极大极小值点。
Third, argument-polar radius curve of polar coordinate system whose pole is geometric gravity is formed, and maximum and minimum value points are searched.
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