查询词典 simultaneous differential equations

The last time when the valves open and close the boundary condition equation and heating systems in the other boundary condition equations, one-dimensional unsteady flow equations of motion and the joint solution of continuity equation, we can find the non-dimensional opening when the valve changes, heating system to calculate changes in surface pressure.

上回阀启闭时的边界条件方程与供热系统中的其它边界条件方程、一维不定常流动的运动方程和连续方程联解，就可以求出当止回阀无量纲开度变化时，供热系统各计算截面压力的变化情况。

In the method, the equation of vorticity is simplified and combined with the definitions of vorticity and divergence , and then restrained by the equation of continuity to set the system of retrieval equations. Three-dimensional wind vector, vorticity and divergence can be got by solving the system of equations. Preliminary test has proved that it is feasible.

该方法从动力学角度出发，将柱坐标中的垂直涡度方程适当简化后，联系涡度散度的定义式，再以大气连续方程作约束，得到一个反演方程组，求解方程组就可得到不同高度层上的三维风场以及涡度、散度，初步检验证明其是可行的。

Finally, to understand and reproduce the results of numerical simulations, we propose a phenomenological noise driven equations describing evolutions of macroscopic variables under the assumption of local energy equipartition and the fluctuation-dissipation theorem. The numerical results of the stochastic equations and those of numerical results from the original Hamiltonian dynamics coincide with each other very well.

最后，为了理解和重现数值模拟的结果，我们通过局域能量均分假设和涨落耗散定理，建立了一个由噪声驱动的宏观变量演化的唯象动力学方程。

NIRS was used to quantify chitin, ergosterol and mycotoxins. Calibration equations and validation equations for these materials were developed.

随着不同模型的定标方程的建立和模型数据库的不断完善， NIRS将会在真菌研究领域发挥越来越大的作用。

Exterior problem ; boundary integral equations; equivalent boundary integral equations

外边值问题；边界积分方程；等价边界积分方程

A new scheme for approximating the solution of 2D Maxwell's equations-the high order symplectic scheme is proposed to overcome the shortcoming of the conventional finite difference time domain. The scheme is obtained by discretizing the Maxwell's equations in time domain based on symplectic scheme with high order, and then evaluating the equation in spatial domain with second or fourth order finite difference approximation.

为克服标准时域有限差分方法的缺陷，引入一种新的数值计算方法－高阶辛算法求解Maxwell方程，即在时间上用高阶辛差分格式离散，空间分别采用二阶及四阶精度的差分格式离散。

It contains boththe finite element equations and finite difference equations in one equation.

拟协调元法是广义协调方程的解，自然满足平衡对弱连续条件的要求。

As we know, the resulting algebraic equations are large systems of non-linear equations with the expanded mixed finite element method for the equation.

用扩张混合有限元方法对其进行离散是常用的方法，其离散化所获得的代数方程组是一很大的非线性方程组。

The transient air gap magnetic fields under different conditions are also calculated and analyzed. The novel finite element method directly using magnetic induction as unknown variable has many advantage. It is analyzed theoretically in detail. Nonlinear eddy current field equations and finite element equations using magnetic induction as unknown variable are developed.

直线电机的磁场是一非均匀、非线性的涡流场，文中对非均匀磁场及材料的非线性进行了分析，提出了相应的解决办法，采用以向量磁位为求解量的传统有限元法，对不同合闸角下筒式复合次级圆筒型直线感应电机的瞬态特性进行了计算与试验分析，对不同条件下瞬态气隙磁场进行了研究。

When the mathematical model is established, the correct connection of two kinds of equations becomes a sticking point for the finite element equations and the analytical expressions to be integrated as a whole equation.

数学模型建立以后，两类方程的正确连接是把有限元方程和解析表达式整合为整体方程的关键。

So it was last week in Selma , alabama.

上星期在亚拉巴马州塞尔马市发生的事件也是这样一个转折点。

The group also spearheads various social programs in China.

该组织还带头参与中国的各种社会活动。