In order to define this irrotationality condition mathematically, let us consider the equation of motion in terms of velocities.

为从数学上确定此无旋性条件，我们考虑以速度为未知函数的运动方程。

A class of nonconforming finite elements are applied to hyperbolic equation with semidiscretization on anisotropic meshes, the optimal error estimates are derived.

各向异性条件下，讨论双曲型方程的一类非协调有限元逼近，给出半散格式下的最优误差佑计。

The one dimensional continuity equations of n-on-p planar PN junction are solved at different boundary conditions. Generalized solutions of photocarrier concentration are given in this paper.

对一维情况下平面PN结的连续性方程进行，给出不同边界条件下光生载流子浓度的一般形式，并对结果进行分析讨论。

The condensability of liquid,the Westphal's effect and the continuous flow condition are not only comprehensively considered,but also the dynamic property of the ball valve being established.

结合现场试验,根据直线电机采油泵运动特性,综合考虑液体的可压缩性、魏氏效应、液体连续流动条件和球阀的动力特性,建立直线电机采油泵球阀运动规律的精确运动微分方程组。