D′Alembert′s principle is used to derive an ordinary differential equation set for free vibration of a discretized square tensioned membrane with geometric nonlinearity.

应用达朗贝尔原理建立了考虑几何非线性的方形张拉膜结构的离散非线性振动方程组；

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On the basis of the elementary equation of atmosphere motion, we consider the nonlinear couples as an external origin, and derive a strong coupled formed KdV equation.

在大气运动基本方程的基础上，考虑南北风场平流效应引起的非线性耦合作为外源，在耦合项非线性逐渐增强的情况下。

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We can't actually go ahead and derive this equation of the wave function squared, because no one ever derived it, it's just an interpretation, but it's an interpretation that works essentially perfectly.

从这个方程中,导出，波函数的平方，没有人可以这样做，这仅仅是一种解释，但这种解释，能解释的很好，自从它第一次被提出来之后。

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