查询词典 kirchhoff

of Theoretical Physics and the physical nature and targets of the disciplinary procedures. In 1859, according to Kirchhoff solar spectra and thermodynamic interpretation of Fraunhofer lines, asserted that the sun and Earth-like existence, in some chemical element, indicating that can be used in theoretical physics, experimental results from the universal laws of astronomical objects to the inherent nature of the astrophysical theory of the beginning.

利用理论物理方法研究天体的物理性质和过程的一门学科。1859年﹐基尔霍夫根据热力学规律解释太阳光谱的夫琅和费线﹐断言在太阳上存在著某些和地球上一样的化学元素﹐这表明﹐可以利用理论物理的普遍规律从天文实测结果中分析出天体的内在性质﹐是为理论天体物理学的开端。

Based on Fresnel Kirchhoff diffraction integral equation, a mathematical model on the diffraction of nonlinear optical media to Gaussian beam is established.

从菲涅耳基尔霍夫衍射积分公式出发，建立了非线性光学介质对高斯光束的衍射模型，通过数值积分，得到了与实验现象符合的计算结果。

In order to reasonably depict four basic problems with friction, one Coulomb friction new form in first Kirchhoff stress is proposed to deal with finite deformation problems, other Coulomb friction form in incremental mode to elastoplastic flow theory; Hilbert function spaces concerning elastoplastical problems with friction are established, so it makes all operations and calculations in the treatise standardized within the scope of reasonably topologic structure; In view of functional extremum, the equivalence between generalized variational inequalities principles in elastoplasticity with friction and corresponding basic problems are testified by inducing Lagrangian multipliers, so it provides a rationally theoretical basis for numerical methods in elastoplasticity with friction; From the viewpoint of variational inequality, the theory of generalized variational inequalities in elasticity and elastoplasticity with frictional constraint is studied, and the uniqueness and existence of the solution of FEM is proofed under the proposed conditions of stress compatibility, and them FEM approximation and a discrete solution are discussed; Based on the principles of generalized variational inequalities in elastoplasticity with friction, direct generalized variational inequalities methods is pretended, which is a natural generalization and development of direct variational methods; Using generalized variational inequalities methods, some examples in metal forming including plane deformation, upset and extrusion are analyzed and the results prove that all the theories and methods in the paper are right, feasible, accurate and advanced.

主要内容有：为了合理地描述金属塑性成形中摩擦约束弹性、弹塑性基本问题，提出和研究了有限变形下以Kirchhoff第一应力表示的Coulomb摩擦定律形式和弹塑性流动理论下以增量形式表示的Coulomb摩擦定律表示形式；系统建立了摩擦约束弹塑性问题的Hilbert函数空间，使本文规范在一个具有合理的代数拓扑结构内进行一切操作和运算；利用Lagrange乘子，从泛函极值的角度系统地阐述和论证了一系列摩擦约束弹性、弹塑性广义变分不等原理与相应的实际问题之间的等价性，它为处理摩擦约束的弹塑性力学数值方法提供了合理的理论基础；从变分不等式的角度出发，阐述了对应于摩擦约束弹性、弹塑性问题的广义变分不等式理论，首次提出了在应力相容性条件下，它的有限元解具有存在唯一性，进而讨论了其有限元近似及离散解法；基于摩擦约束弹塑性广义变分不等式原理，首次提出了直接广义变分不等式方法，这一方法是直接变分法的合理推广和发展；利用直接广义变分不等式方法对金属压力加工中的平面变形问题、镦粗、挤压等塑性成形问题进行了分析计算，验证了该理论和数值算法的正确性、实用性、精确性和优越性。

Thirdly,as the basic study for UWB radiating and scattering,this paper improves simulation of near to far field transformation technology based upon Kirchhoff Integral in Finite Difference Time Domain.

作为分析超宽带信号辐射与散射的基础，本文改进了时域有限差分方法中基于基尔霍夫积分的近远场变换技术，它的优点在于实现简单，降低了存储内存要求，既能计算远区场又能计算近区场，计算结果表明这种变换方法非常有效。

In this paper, Kirchhoff formula has been transformed from surface integral form into a line integral form.

将经典的面积分形式的Kirchhoff公式转换为线积分形式。

It applied Kirchhoff expression to FDTD numerical computation of acoustic scattering problems,and iterated near field on the integral surface to far field that was contributed to,which could b.

针对此问题，提出一种新的外推方法，它将柯西霍夫公式应用于FDTD数值计算中，将积分面上每一步的近场都叠加到它有贡献的远场时刻上去，近远场变换可以与FDTD的场分量迭代同步进行，不需要将外推边界上每一时间步的场值都存储下来，减少了存储空间。

And then we proved that Kirchhoff law can be applied to describing traffic flow characteristic.

在此基础上，证明了基尔霍夫定律在网络交通流描述中的适用性，从而运用完善的电路网理论来分析了道路网交通流特性。

Kirchhoff's law is an important law that students first meet to resolve the complicated circuit.

也许他们认为串并联电路的知识就可以解决所有电路的计算问题。

A mathematical model, which describes a class of nonlinear electrical oscillator, is created by the Kirchhoff's First Law.

基于基尔霍夫第一定律建立了一类非线性周期振荡电路的数学模型，分析了周期激振力变化时对系统动力学行为的影响。

After Kirchhoff's law a black body also emits the maximum possible amount of radiant heat.

根据克希霍夫定律，一个黑体也放射出尽可能多的辐射热量。

Liapunov—Schmidt method is one of the most important method in the bifurcation theory.

Liapunov—Schmidt方法是分叉理论的最重要方法之一。

Be courteous -- even when people are most discourteous to you .

要有礼貌──即使当別人对你最不礼貌的时候。