查询词典 simultaneous differential equations

Power-law fluid is used to describe the Non-newtonian rheological property of the produced fluid in a polymer-driving well; the governing equations, boundary and initial equations of power-law fluid in eccentric annuli with the inner cylinder reciprocating axially is established in bipolar coordinates system; formulas of instantaneous flow rate and stress distribution on the outwall of the inner cylinder of the unsteady flow of power-law fluid in eccentric annuli with the inner cylinder reciprocating axially are established.

在理论上，用幂律流体模型描述了聚合物驱油井产出液的非Newton流变性；建立了双极坐标系下幂律流体在内管做轴向往复运动的偏心环空中非定常流的控制方程及边界条件和初始条件方程；建立了双极坐标系下幂律流体在内管做轴向往复运动的偏心环空中流动时瞬时流量和流体在内管壁上的压力分布计算公式。

It is almost impossible to access the analytical solutions of relaxation equations, so the computer program for numerical solutions is developed. By means of the program and the Bloch equations, the steady state solutions of two...

在此基础上，编制了弛豫方程组数值解的计算程序，分别用此程序和Bloch方程计算了双自旋体系在不同情况下的稳态解，并对计算结果进行了简要的分析和讨论。

The contact curved surface equations and the contact plane surface equations have been worked out. The boundary curve eqations of the contact surface have been founded.

运用数学分析方法，首次对板式楔横轧工艺的轧件稳定旋转条件、轧件不产生缩颈拉裂条件进行了理论研究。

It showed that the inverse circular function equation had the best fitting to the process of yellow soil releasing cadmium at conditions with different acid rain. Besides, polynomial equations and two-constant equations can also describe this process properly.

结果表明，反三角函数方程对多种酸雨条件下黄壤吸附态镉释放过程的拟合度最佳，此外多项式方程、双常数方程也能较好地描述这一过程。

Based on the projection theorem in the finite-dimensional inner product space, by making use of the generalized singular value decomposition and the canonical correlation decomposition of matrix pair simultaneously, we transform the least-squares problems of the abovementioned inconsistent matrix equations into the problems of solving the consistent matrix equations over given matrix set, and obtain the general expressions of the corresponding least-squares solutions.

S使得‖-X~*‖=‖-X~*‖，其中‖·‖为Frobenius范数，S分别表示矩阵方程 AXB=D，AXA~T+BYB~T=D，AXB+CYD=E和矩阵方程组=，=在一般矩阵集合或对称矩阵集合上不相容时的最小二乘解集合。

For the Riemann boundary value problems for the first order elliptic systems , we translates them to equivalent singular integral equations and proves the existence of the solution to the discussed problems under some assumptions by means of generalized analytic function theory , singular integral equation theory , contract principle or generaliezed contract principle ; For the Riemann-Hilbert boundary value problems for the first order elliptic systems , we proves the problems solvable under some assumptions by means of generalized analytic function theory , Cauchy integral formula , function theoretic approaches and fixed point theorem ; the boundary element method for the Riemann-Hilbert boundary value problems for the generalized analytic function , we obtains the boundary integral equations by means of the generalized Cauchy integral formula of the generalized analytic function , introducing Cauchy principal value integration , dispersing the boundary of the area , and we obtains the solution to the problems using the boundary conditions .

对于一阶椭圆型方程组的Riemann边值问题，是通过把它们转化为与原问题等价的奇异积分方程，利用广义解析函数理论、奇异积分方程理论、压缩原理或广义压缩原理，证明在某些假设条件下所讨论问题的解的存在性；对于一阶椭圆型方程组的Riemann-Hilbert边值问题，利用广义解析函数理论、Cauchy积分公式、函数论方法和不动点原理，证明在某些假设条件下所讨论问题的可解性；广义解析函数的Riemann-Hilbert边值问题的边界元方法是利用广义解析函数的广义Cauchy积分公式，引入Cauchy主值积分，通过对区域边界的离散化，得到边界积分方程，再利用边界条件得到问题的解。

On detailed study of the central difference finite volume method proposed by Jameson, discrete formulae of 3-D Euler equations and N-S equations are presented.

详细研究了Jameson的中心差分有限体积法，推导了Euler方程和N-S方程的空间和时间离散公式。

By central difference in time and space and boundary conditions, equilibrium equations of warp are transformed into the definite equations and solved by Newton\'s iteration.

通过在时间和空间上对拖网曳纲平衡方程组进行中心差分以及首尾边界条件的处理，将该方程组转换为定解代数方程组，并采用牛顿迭代法求解。

In addition, the membrane polarization time is gained from cell's simplified equivalent circuits and approved by system time constant of the state space equations of cell suspended system. Secondly, Laplace equations of the ideal model are built based on Faraday's Law, Gauss's Law, and charge conservation to analyze and calculate the amplitude and variation of transmembrane potential detailedly.

为了对微生物脉冲电场效应进行理论上的分析，首先，本文从细胞膜的结构、组成及功能入手，建立了微生物细胞的介电模型，求出了细胞膜的介质极化时间常数，并通过系统状态空间方程对其进行了验证。

We've found that on symplectic manifolds there exists a series of Euler-Lagrange cohomology groups different from both de Rham and harmonic cohomology in general and proposed a set of general volume-preserving equations that contain the Hamiltonian equations as a special case.

中文摘要：我们发现在作为经典力学中的相空间的辛流形上有可能存在不同于de Rham上同调和调和形式的上同调，称之为Euler-Lagrange上同调；提出相空间上保体积的一般方程，通常的正则方程是其特殊形式；进而推广了经典力学中著名的刘维定理；同时把Noether定理与上同调联系起来。

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。