导出方程

In the new model, the similar approximation can be obtained from the integral expression of vector potential and the Lorentz gauge, therefore a set of state equations like the MNA in traditional PEEC can be built.

在本文的方法中从矢量磁位的积分表达式和洛仑兹规范出发，可导出与传统PEEC模型中的改进节点法方程相应的状态方程。

Firstly, the article expatiates the concept of fuzzy reliability and the relation between random and fuzzy. It presents a list of random-finite element formula that is suitable for the reliability analysis for mechanical rigid frame system. Secondly, it presents two arrangements' reliability analysis methods that fit for component and fabric system. Finally, according to the characteristic of engineering mechanical, the article first brings forward half random-half fuzzy"stress-intensity intermeddle model"for mechanical intensity analysis, and according to Gerber equation for weariness intensity calculation, the article presents fuzzy number's calculating principle and the fuzzy reliability analysis method for engineering structure weariness intensity.

首先阐述了模糊可靠性概念、随机性与模糊性的关系；在导出摄动随机有限元法随机变量的变分原理、随机有限元控制方程和递归方程组基础上，给出了适合于工程机械刚架系统可靠性分析的随机有限元列式；给出了构件和结构体系两个层次的可靠性分析方法；根据工程机械的特点，首次提出机械强度分析的半随机半模糊"应力-强度干涉模型"，并依据疲劳强度计算的Gerber方程，给出了模糊强度的模糊数运算法则及工程结构疲劳强度模糊可靠性分析计算方法，该方法具有简便实用的特点和普遍意义。

For different polynomials g, if the characteristic polynomial of a n matrix A is irreducible, then we get some theorems to determine matrix equations g =A solvable; if it is reducible, then, to see n-dimension space vectors M over a field F as F-module, we use module theory to determine these equations solvable such that it is simpler and clearer to investigate these questions.

对于不同多项式g，当n阶矩阵A的特征多项式为不可约的，我们给出了矩阵方程g=A有解的判定定理；当A的特征多项式为可约的，把域F上的n维线性空间M作为由A导出的F -模，我们利用模论知识来决定矩阵方程g=A有解性，从而使这一问题变了简单，研究思路更加清晰。

Application of HHGL to lithium atom As a starting point for exactly solving schrodingerequation for lithium,the part has twofold purpose,one isto derive the coupled hyperradial differential equation,and discuss whether HHGL can be used or not,the other isto build the symmetric basis functionfor twodimensional irreducible representation of 〓 permutationgroup and estimate the ground-state eigenenergy.

首先根据Pauli原理的要求，将N电子原子的波函数向〓群不可约表示之基展开，积分掉角度部分，推导出N电子原子的超球径耦合微分方程，其形式与氦原子耦合微分方程相似，差别表现在矩阵元〓的计算上。

By the principle of penalt function, the irrotational fluid field is constrained, and author has proposed the Difference Method for distinguishing fluid vortex modes among the natural modes of coupled systems. Author has calculated the real frequencies with the extra deductive method, and discussed the influence of the numerical solution due to the irrotational constraint.

对于流体有限扰动时的非线性耦合系统的有限元分析作了一些探讨，给出了非线性系统的基本方程、变分原理及有限元方程，并具体地导出了三维几何非线性流体单元的切线刚度公式，采用增量形式的Newmark预报——校正逐步积分法计算系统的动力响应，由Newton-Raphson迭代法及其修正方法求解系统的非线性方程组，还列出了不平衡力余量检查和位移迭代增量检查等迭代收敛判断准则。

In the low-low satellite to satellite gravity mission, the intersatellite range and range-rate data are the observable values, while the intersatellite acceleration can be derived from the range-rate through digital differential. Using acceleration data, people can avoid solving the variation equations of the satellite motion and simplify the observation equations. But on the other side, the digital differential will amplify the observation noises and finally affect the solved geopotential accuracy.

低低卫星跟踪卫星的观测量是两低轨卫星的星间距离或星间速度，星间加速度由星间速度通过数值微分导出，用星间加速度作为观测量可以避免解算卫星运动的变分方程，简化观测方程的建立，但数值微分会使观测噪声放大，从而影响重力位的解算精度。

To establish the constitutive equation of material, the metric tensor for stress , strain and their transformation equations between different configurations are derived, and basic theory of finite deformation as well as elasto-plastic deformation criterion are studied. By analyzing the applicability of different element models, four-node quadrilateral degenerated Mindlin isoparametric element is adopted because of its good versatility, and the element stiffness matrix is derived. The static implicit elasto-plastic finite element equation for complex skin stretch-forming is put forward based on Updated Langrange formulation.

本文首先系统地阐述了有限变形的相关基本理论，针对板料成形建立了应力应变度量张量及其相应的转换关系；介绍了材料的屈服准则、塑性变形强化规律、塑性流动规律以及加、卸载准则，并在此基础上建立了有限变形各向异性弹塑性本构方程；对板料成形的单元模型进行了分析，针对飞机蒙皮零件特点，采用通用性强的四节点四边形退化Mindlin等参壳单元进行成形模拟，并导出其单元刚度矩阵的具体形式；基于以上研究，以逐级更新Langrange描述的持续虚功率原理为基础，建立了率形式的复杂蒙皮拉形过程静态隐式弹塑性有限元方程。

In the point of view of interacting forces among micro-particles in liquid pure substance and according to argon model and theorems and rules in semi-metal structure theory of organic molecules created by one of authors, a new theoretical equation of the liquid molar volume V at the normal boiling point to pure substance is proposed.

从液体纯质中的微观粒子间的相互作用力方面考虑，按照作者创立的氮模型理论和有机分子的半金属结构理论中的定理定则，导出液体纯质在正常沸点下的摩尔体积V理论方程，给出了理论方程成立的数学证明。

And the conservation laws of moment and momentum are obtained by the combining the tiny element analysis method in continua mechanics with variation principle in analytical mechanics.

论文摘要：本文在建立时变边界挠性体的动力学方程时，将并入的质量对挠性体的作用当作时变边界上的表面力，并将连续介质力学中的微元分析法和分析力学中的变分原理相结合，导出了时变边界的变质量刚体的动量和动量矩矩方程。

Conservation of mass.conservation of moment muni and conservation of energy are basic regularity obeyed by all movement in nature.For a certain problem in natrue .if we quantify the corresponding conversation law . we can deduce partial differential equation reflecting this problem .and every differential equation reflecting a special physical phenomenon on certain codition.

质量守恒、动量守恒和能量守恒是自然界一切运动所遵循的基本规律，对于自然界的某一特定问题，如果把相应的守恒律数量化，就导出刻划这个问题的微分方程，每一个微分方程都在一定条件下刻划了某一特定的物理现象。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。