查询词典 finite difference approximation

The Rayleigh method, the Ritz method, the Galerkin method, and the finite difference method are extended to solve the engenvalue problem of the plates.

把瑞雷法、李兹法、伽勒金法和有限差分法推广到了这种板的特征问题的求解。

In this paper, we present a class of equation model for image denoising and edge enhancement. The model is based on robust statistics error norm and variational theory. By analysing the parameters of the equation and designing the methods of module partitions, the numerical experiments reach a good result and the parallel efficiency has been improved remarkably with finite difference method.

本文基于稳健统计误差模函数及变分原理构造了一类用于图像去噪、增强边缘的方程模型，对相关参数进行了分析，设计了该方程有限差分数值求解的并行算法，并对分块模型及实现过程进行改进，提高了并行效率，在此基础上完成了并行数值实验，并对结果就误差模选取、并行效率等方面进行了分析。

Aiming at these problems, we have designed the processing workflow to effectively suppress the surface Wave interference, regular interference, high energy interference, and other random noise interference. The treatment clue was from thick to thin. Firstly, the spectral analysis method was used to establish macroscopic velocity field. Then, the ray tomography method was used to enhance the accuracy of velocity analysis and to establish a more accurate velocity model. Finally, the finite difference pre-stack depth migration on method in -k domain was adopted to solve the imaging problem of subsalt and salt dome flank.

通过合理组织处理流程，有效压制了面波干扰、规则于扰、强能量干扰和随机噪声干扰；采用由粗到细的思路，先利用谱分析方法建立宏现速度场，再利用射线层析成像方法提高速度分析精度，建立了较为准确的速度模型；利用频率－空间域有限差分叠前深度偏移解决了盐下及盐丘侧翼的成像问题。

In order to investigate and develop numerical calculation method for Schr odinger equation, we apply the finite difference method to eigenvalue problems in quantum mechanics.

为研究和发展薛定谔方程的数值计算方法，本文将有限差分法应用到量子力学求解薛定谔方程本征值问题。

Furthermore, this model is expanded in two aspects: on the one hand, through the introduction of the theory of the Fault Tree, this thesis analyzes the difference between the fault-diagnosis in the recovering flow and that in the traditional flow, thus concluding that the fault-diagnosis in the recovering flow is just a tracing-back process of the directed-graph and the Fault Tree; on the other hand, a finite self-restoring state machine is constructed on the directed-graph model, thus providing the theoretical basis for the realization of the auto-recovery model.

随后在两个方面对该模型进行了扩展：1。通过引入故障树的方法，并在分析了恢复流程故障诊断与传统故障诊断的差异之后，总结出恢复流程的故障诊断就是一个基于有向图和故障树进行回溯的过程；2。基于有向图模型建立了一个有穷自动状态机，为自动恢复与模型的实现提供了理论基础。

The diurnal, semidiurnal and shallow-water tides and tidal currents in che Bohai Sea are computed using finite-difference method based on two-dimensional nonlinear tidal wave equations.

本文采用二维非线性潮波微分方程组的有限差分方法同时计算了渤海全日、半日和浅水潮。全日和半日潮计算结果与实测符合良好。

An improved shift operator finite-difference time-domain method for general dispersive medium based on the implementation of infinite impulse response filter in digital signal processing technique is presented.

借鉴数字信号处理技术中的无限脉冲响应滤波器实现的思想，提出一种适用于通用色散介质的改进移位算子时域有限差分（shift operator finite-difference time-domain，SO-FDTD）方法。

The finite-difference time-domain method was used to simulate the propagation of P polarized light Gaussian beam in a single subwavelength metallic slit surrounded by gratings.

利用时域有限差分方法，模拟了P偏振光高斯光束入射到金属银亚波长细缝与光栅结构的透射情况。

Many methods, including difference methods,collocation methods and standard finite element methods for singular parabolic equations have been proposed and analyzed ,and some good results have been obtained.

但利用非标准有限元方法，对奇异微分方程进行研究的文章迄今很少见到。时空有限元法将时间和空间两个变量统一起来，在时间和空间两个方向上同时发挥有限元的优势，实现时间和空间两个方向的高精度。

The major implementations of the developed model include: Pseudo-spectral and finite-difference schemes are employed to approximate the spatial-differential operators in the horizontal and vertical directions, respectively. A second-order Runge-Kutta method is adopted to integrate in time for the velocity field and the free-surface elevation. The solenoidal condition of the velocity field is satisfied by solving the transformed pressure Poisson equation. A modified secant method is used to accelerate the iterative solution of the non-separable Poisson equation.

模式的主要数值方法包括：分别以拟频谱法以及二阶有限差分法近似控制方程与边界条件中的水平与垂直导数；以二阶Runge-Kutta法进行非稳态的自由液面位移与流场速度的时间积分；利用改良式割线叠代法求解计算区间中不可分离的压力Poisson方程式，以满足不可压缩流条件。

The studies on the developing of new media are very important to the increasing of the area density of HDD and to the implementation of hybrid recoding technology.

光磁混合记录方法，是一种可以突破超顺磁极限的限制，并进一步提高硬盘记录密度和读写速率的一种新型超高密度信息存储方式。

In io, mTOR inhibition promotes T cell anergy under conditions that would normally induce priming.

体内研究中，在正常可激发免疫反应的条件下，抑制mTOR可促使T细胞无能。