set of equation

The mathematical equation of spatial evolution and time advance, the immersed boundary method that are used to calculate the force between the fluid and the roughness element, and the set of entrance and exit boundary conditions are briefly introduced.

对于空间演化和时间推进的数学方程，计算流体与粗糙元之间作用采用的内嵌边界方法的原理和使用，入口和出口边界条件的设置等进行了简要的介绍说明。

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For the 2+ 1 dimensional integrable KZ equation'a set of infinitely many trun-cted symmetries with infinitely many arbitrary functions of time are obtained by using formal series symmetry method.

对于2+1维的可积的Khokhlov-Zabolotskaya方程，利用形式级数对称的方法，得到了一包含无穷多任意时间函数的无穷多截断对称。

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Under the assumption that the electron beam is single-velocity and one-dimensional, the transmission equation of space charge wave set up in the conical electron beam is derived and the process of noise impedance transformation is obtained.

在单速、一维假定下，推导了球形收敛电子注上的空间电荷波传播方程和噪声阻抗的变换过程。

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In light of introduction of the method to set up mathematical modeling, the article takes up analysis on circuit using time domain differential equation method and frequency domain Laplace transform method ( LTM).

通过介绍建立数学模型的方法，对利用时域中传统的微分方程法和频域中经典的拉普拉斯变换法对电路进行了分析。

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In the Attribute Petri Net, the start rule of transition and calculation of place marking are different from traditional Petri Nets. Therefore, we redefined APN transition fired condition, reachability marking set, the incidence matrix and status equation.

在属性Petri网中，变迁的启动规则以及库所标识的计算都有别于传统的Petri网，因此，本文重新定义了APN的变迁点火条件、可达标识集、关联矩阵和状态方程。

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