wave trough

基本解釋

Besides, the propagation speed will be different part of the wave, this leads to deformation of a wave trough or wedge in the course of motion.
而且移行速度在波槽或脊的各部分不同，將引起槽線或脊線在移行過程中出現(xiàn)自東北向西南歪斜的變形。
The results indicate that the disintegration of the jet column is caused by the surface waves propagating along the jet body. The jet breaks up at the wave trough.
結果表明：沿射流柱表面?zhèn)鞑サ谋砻娌ㄊ且鹕淞髦扑榈闹饕蛩兀扑辄c位于表面波的波谷。
In supersonic flow, results indicate that the disintegration of the jet column is caused by the surface waves induced by aerodynamic forces and the breakup point is at the wave trough.
結果表明：在超聲速氣流中，射流柱破碎是由迎風面的表面波引起的，破碎點位于表面波的波谷。

But Google too had been through a trough just before, after the failures of Wave and Buzz.
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