The force and moment exerted on the solid body are expressed as the rate of change of the first-and second-order kinetic vorticity moments, respectively.

作用在任意运动物体（系）上的力和力矩可以分别表示成流场中动力学涡量的一阶矩和二阶矩随时间的变化率。

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Secondly, the procedure of tunnel lining based on First Order Second Moment(FOSM) and JC method is presented to calculate the reliability of tunnel lining.

根据提出的可靠度计算理论和方法，编制了基于一次二阶矩和JC法的可靠度计算程序。

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The parameters of the model are fuzzily processed and the fuzzy risk can be evaluated by using the modified first order second moment method.

通过对模型中的参数进行模糊化处理，用改进一次二阶矩法计算了地下水过量开采的模糊风险率。

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