查询词典 finite difference approximation

The formulation of power system transient stability preventive control based on optimal power flow is presents in this thesis, in which multicontingency is considered. The infinite dimensions nonlinear optimization problem in which differential-algebraic equations are existed is changing into finite dimensions difference-algebraic equations by implicit trapezoid method.

建立了基于最优潮流的电力系统暂态稳定预防控制模型，通过隐式梯形法将含有发电机动态微分-代数方程和暂态稳定约束的无限维优化问题转换成有限维的常规静态最优潮流问题。

Gas insulated switchgear ; partial discharge ; ultra high frequency method ; finite-difference time-domain ; high voltage insulation technology

气体绝缘组合电器；局部放电；超高频法；时域有限差分法；高电压绝缘技术

In the process of magnetic field analysis,magnetic field method and unequally spaced net finite difference method are used to obtain accurate data.

根据分析计算的结果，对磁流体密封进行了优化设计和实验验证，优化设计出的装置体积和重量降低了 50 %以上。

By use of the time split method, a conservation difference formula is established to find the solution to the shallow water equation based on the finite volume control method from integral equations.

作者中文名：李光炽；王船海；周晶晏摘要：采用二分步法，从积分型方程出发，在有限控制体上建立守恒型差分格式，对二维浅水波方程进行求解。

In order to clearly recognize the geophysical response of carbonate reservoir,based on preliminary recognition of Ordovician carbonate reservoir under the basal surface in Tahe oilfield,some regular vug models and random arranged vug models were designed and built. The variable-grid finite difference method was used to simulate the seismic wave propagation in these models. Then,the seismic records of the models were analyzed and the effect to seismic reflections caused by vug is studied. The impact rule of regular vug scale and random arranged vug density on seismic attributes was obtained.

为了研究碳酸盐岩储层的地球物理响应特征，在对塔河油田奥陶系风化面下碳酸盐岩储层初步认识的基础上，利用随机介质建模技术，设计并建立了一系列碳酸盐岩储层规则孔洞和随机孔洞模型，并应用变网格有限差分法对地震波在孔洞模型中的传播进行了正演计算，对模拟得到的地震属性进行了分析，研究了孔洞对地震反射特征的影响，获得了规则孔洞尺度以及随机排列孔洞密度对地震属性的影响规律。

The propagation of electromagnetic pulses in uniform magnetized plasma is studied using the finite-difference time-domain method by means of Z transforms. The Z transform formulation of FDTD method is derived.

通过Z变换的方法，将与频率有关的磁化等离子体的介电常数由频域变换到Z域，推导了Z变换形式的时域有限差分法计算式，模拟了电磁脉冲在磁化等离子体中的传播。

The equations of the towed cable motion are based on Ablow and Schechter model and six degree-freedom ordinary differential equations are used in the analysis of the motion of a towed body. The partial differential equations are discretized by finite difference method and the transient values of towed body depth and cable tension are computed by Newton Iteration when the heave compensation system performs and the length of the cable varies.

拖缆动力学模型基于Ablow and Schechter模型，拖体采用水下运载体六自由度方程模拟，运用有限差分法离散偏微分方程组和牛顿迭代法计算变缆长情况下拖体深度与拖缆各点张力的动态取值。

In the paper,a three-dimension finite difference scheme is presented to examine the stresses fields in the vicinity of a free rectangular corner of a l aminate subjected to a thermal loading.

对层合复合材料自由角附近的层间高应力问题，提出了一种三维有限差分法方案计算层合复合材料在变温下的自由角附近的应力场。

We synthesize the beamlet source and beamlet records in the wavelet domain using both rectangle and Gaussian windows and then extrapolate the synthesized data with a Fourier finite-difference operator.We test the method using the standard Marmousi model.

我们在小波域中，分别应用矩形窗和Gaussian窗合成了小波束源和小波束记录，并基于傅立叶有限差分算子，对marmousi模型进行了叠前深度偏移试算。

The obtained results a re compared with analytic solution and those from integral equation and other me ans. It is shown that the staggered grid finite difference method combined with the Biconjugate gradient iterative solver processed with divergence correction and incomplete Cholesky decomposition procedures can efficiently improve the three dimensional electromagnetic calculation with high accuracy and stability.

经与解析方法、积分方程等其他方法的计算结果对比表明，交错网格有限差分法结合散度校正和不完全乔累斯基分解预处理的双共轭梯度迭代方法进行正演计算，速度快、精度高、结果稳定，能适应三维复杂介质的数值模拟，为三维电磁反演奠定了基础。

Effective local search tactics reaches local searchers when they are ready to buy - with every way that it is possible for them to buy from you.

有效的地方搜索策略达到当地的搜索，当他们准备购买-以各种方式，这是他们有可能从您那里进行购买。

The first two are periodic sentences for their beginnings; and the fifth and the last are also periodic sentences each for the embedding of a parenthetic structure.

1960年代中后期，当战后女权主义和当时的许多其他抗议运动在西欧和北美发展成某种势力时，性别的概念演绎成补充和延伸生物性别差异的概念。