The vibration frequency of box gird is usually calculated by the elementary beam theory, but it will lead to a large error because of the existence of shear lag effect and shear deformation.

由于剪力滞效应及剪切变形的存在，箱梁的弯曲振动频率按照初等梁理论计算往往存在较大的误差。

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The elementary exposure pattern of a variable rectangular electron beam exposure machine is a rectangle.

可变矩形电子束曝光机的基本曝光图形是矩形。

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Coupled laser array, which realizes phase locking of elementary lasers with evanescent waves coupling, is a promising scheme to realize coherent beam combination.

耦合激光器阵列可以通过激光器之间的倏逝波耦合实现相位锁定，是有望实现光束相干合成的方案之一。

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