差分方程

The other approach is to use finite difference method to solve PB equation and incorporate the solution into SD simulation, which produces our FDSD simulation procedure.

将有限差分法求解PB方程的方法与随机动力学相结合，得到FDSD模拟程序。

Using the method of finite difference to discrete the governing equation,the elastic-plastic dynamic response of a simply-supported steel beam subjected to stepped loading and fire loading was investigated.

利用有限差分离散控制方程进行数值分析，研究了火侵袭时简支钢梁在阶跃载荷作用下的弹塑性动力响应。

The finite difference equation was built by using elemental energy balance of reinforced concrete beam with three surfaces exposing to fire based on the thermal properties of concrete. The influence of the physical or chemical reaction of free or combined water in concrete on the temperature field of concrete was considered by magnifying the specific heat of concrete.

根据三面受火钢筋混凝土梁离散体积单元的能量守恒原理，建立了有限差分平衡方程，在合理确定混凝土热工参数基础上，采用增大混凝土质量热容的方法，考虑混凝土中自由水与结合水的物理化学反应对混凝土温度场的影响。

The electrostatic potential was calculated by solving the Poisson- Boltzmanne equation using the finite difference method.

三种金属硫蛋白的静电势通过有限差分方法求解Poisson-Boltzmann方程得到。

Being aimed at the temperature field of finite heat propagation velocity, we make physical analysis and discussion.

利用拉普拉斯变换和差分方法分别对双曲线型导热方程进行了理论求解和数值分析计算，并对热量传播速度为有限值的温度场做了物理方面的分析和讨论。

In this paper, we consider hyperbolic conservation laws, and the following work has been done to the finite volume method on unstructured meshes :In preface , we introduce the backupground of the oringe of the finite volume method, and point out the limitation of the finite difference methods and the finite element methods, and import the finite volume method.

本文主要考虑双曲型守恒律方程，对二维非结构三角形网格有限体积方法作了如下工作：介绍了有限体积方法的产生背景，指出了有限差分方法和有限元方法中的特点，对有限体积方法的产生和发展给出了比较详细的分析。

Starting from the fundamental equations of stochastic medium theory, the ore-drawing with inclined wall boundary conditions is discussed in the paper.

本文从随机介质理论的基本方程出发研究倾斜壁边界条件下的放矿规律，在易于求解的仿射坐标系中，应用差分方法对矿岩移动的速度场进行了确定。

Thesolutions compose self-contained inner product space (weight function is constant 1),i.e., they are basic series of Hilbert space; hence any internal waves could beexpanded into generalized Fourier series. With difference method, Sturm-Liouvilleequation is transformed to matrix eigenvalue problem. Each eigenvalue is related to ahorizontal wave number, and relevant solution is a certain mode of internal wave.

其解系构成完备的加权(权函数为1)内积空间，即Hilbert空间，从而内波现象可以展成该解系的广义Fourier级数；采用差分方法，将 Sturm-Liouville 方程转化为矩阵特征值问题，每一个特征值对应一个内波波数，该特征值对应的解则是内波的某一模态。

With the other conditions remaining unchanged, the conical nozzles have the best half angle of divergence at about 12 5°,(ranging between 10° and 15°).

本文在Euler及Navier Stokes方程的基础上，利用三阶ENO差分格式计算了轴对称喷管的流动，得到了与实验较一致的结果。

First of all, the report introduced evolution, achievments and problems in the study of anisotropy in the inner of earth. The first-order hyperbolic system of equations is work out, which is used to describe the wave motion in 2D transversely isotropic media. Utilizing the characteristics of free-divergence, We have imposed MacCormack theme that is used to simulate multicomponent records in anisotropic media and have developed a fast high order vectorized finite-difference algorithm adapted for the vector supercomputer.

本文首先阐述了地球内部介质各向异性研究的沿革、成就和问题，接着给出了描述二维横向各向同性介质中波动的一阶双曲型方程，利用其自由发散特性，构制了各向异性介质中多波多分量地震记录数值模拟的MacCormack算式，导出了适用于并行计算的二维横向各向同性介质中波动的有限差分模拟算子，该算子具有可并行化计算、相位差小等优点。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。