S-type blades are usually used in such fans because of the absolute geometrical symmetry.

由于几何形状完全对称，S型叶片是可逆风机中比较理想的叶片。

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His formal systematization of plans, elevations, and sections effectively transformed architectural design into a selective modular typology in which symmetry and simple geometrical forms prevailed.

他创建的平面、立面和剖面的形式系统对建筑设计产生了深远影响，使建筑设计成为对称和简洁几何体的选择性的标准化的类型学。

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Mathematics recognises many sorts of symmetry, not all of them amenable to these sorts of geometrical analogy.

ECONOMIST: Particle physics makes sense, but it assumes too much