插值法

The simulation shows that the high accuracy FFT with Blackman windows has the higher accuracy ,especially for the phases.

在谐波分析中论文对比分析了FFT算法、高精度FFT法、递归FFT法、STFT法的算法优劣性，采用了加Blackman窗的插值高精度傅立叶算法，仿真分析表明高精度FFT算法精度远高于FFT，尤其是相位精度的提高更为明显。

The cubic interpolation polynomial is got firstly in the given sub-range of the hydrophone's sensitivity-frequency curve by using the Akima curve smoothed algorithm, and the maximum of the polynomial is calculated in the sub-range by using the one dimension extreme value continued fraction algorithm, finally the frequency of the hydrophone is got.

频率测试是在灵敏度详细测试的基础上，采用阿克玛曲线光滑算法求出检波器幅频特性曲线在给定子区间上的三次插值多项式，再利用一维极值连分式法求出该区间上多项式的极值，从而求出检波器的频率值。

This is an untouched measuring way. The cameras are calibrated in the way of RAC two steps, first. With the polynomial interpolation, the pictures catched from the steel plate are treated to detect the edge in subpixel with a cross window arithmetic operators, which can fit non uniform illumination, keep the edge character and do filter in a better way. Three-dimensional scenery could be rebuilt from the two-dimensional pictures with the methods of least square fitting and contradictorily clairvoyance. Thus, the distance and its variance of two points in the given position of the plate can be achieved. It is expected that this study can provide a new and useful tool to the research on the theory of distortion of line heating.

这种非接触的测量方式，采用RAC两步法对摄像机进行标定，然后对采集到的钢板图像进行分析处理，通过多项式插值的方法，采用具有保持边缘特征和滤波功能，且能适应非均匀照明的十字窗图像边缘检测算子进行象素级边缘检测，再用最小二乘拟合法和逆透视法对二维图像进行三维重建，便可测出钢板上给定点的距离及其变化值，以期为水火弯板的变形机理研究提供一种新的检测手段。

To reduce the evil influence of the window effect to discrete Fourier transform spectrum analysis, interpolation equations of generalized cosine window function with different K are derived.

为了减少加窗效应对基于离散傅里叶变换频谱分析的测频算法产生的不良影响，推导了不同K值下，广义余弦类窗函数的频谱及幅度比值法插值校正公式。

In image processing, method as follows will be introduced in this paper: a method combining image threshold iterative segmentation with threshold interpolation, edge detection operator Sobel and LoG, edge linking method using delation operator based on mathematical morphology, using boundary tracking and projection method in edge distill process. Through this method, measurement of wheelset will be met precision demand.

本文阐明了图像的分通道自动采集过程，以及对采集到的原始图像进行预处理过程，达到图像去噪声的目标，本课题采用了阈值分割中迭代阈值和阈值插值相结合的方法，Sobel算子、LoG算子边缘检测算法，基于数学形态学的膨胀运算子进行边缘断点连接以及目标提取中的投影法和边缘跟踪方法，使得提取轮对图像边缘达到测量精度的要求。

The advantages of the meshless and finite element methods were combined in a coupled finite element and meshless radial point interpolation method.

为了发挥无网格法和有限元法各自的优势，提出了径向基点插值无网格法与有限元直接耦合的计算方法。

The contents of this course include: the mathematical basis of FEM, the generic solution principles and expressions of elastic mechanics issue, the construction of element and its interpolation function, iso-parametric element and numerical integral, solution of linear equations, some practical issues of FEM modeling, brief introduction to typical commercial FEM packages, FEM for truss, plate blending and shell, and FEM for heat exchange and dynamics.

课程内容主要包括：有限单元法的数学基础、弹性力学问题有限单元法的一般原理和表达格式、单元和插值函数的构造、等参单元和数值积分、线性方程组解法、有限元建模的若干实际问题、典型商用有限元分析软件简介、杆件结构力学问题的有限单元法、平板弯曲问题的有限单元法、一般壳体问题的有限单元法、热传导问题的有限单元法、动力学问题的有限单元法等。

Firstly, the three-dimension boundary question and its corresponding variation question concerning the point-source electrical field on a 3-D structure are presented. Secondly, the finite element method is used to solve the variational equation. The study area is divided into many tetrahedral elements. Then, we interpolate with a tri-linear function in each element. So, the variational equation is converted into a linear equation system. Finally, taking into account saving of time, we make use of symmetric successive overrelaxation preconditioned conjugate gradient algorithm to solve large linear system, and obtain the potential value of each node, resulting in the calculation of the apparent resistivity values on the ground surface.

首先给出了三维构造中点源电场的边值问题以及相应的变分问题；然后利用有限单元法求解变分问题，采用四面体单元对研究区域进行剖分，在单元中进行三线性函数插值，将变分方程化为线性代数方程组；最后，考虑到节约计算时间，利用对称超松弛预条件共轭梯度迭代算法求解大型线性方程组，得到了各节点的电位值，进而计算出地表的视电阻率。

Secondly, point out that meshless method is different from finite element method in handling boundary condition and numerical integral because the approximation function of meshless method is not inserted function, it have itself special methods. Deduces meshless Galerkin essential equation of parabolic partial differential equation with the method ofweighted residuals------Galerkin. Furthermore, discusses the main factors which may effectthe calculation precision and give some suggestion with which can get the best result.

其次，由于无网格法的近似函数不是插值函数，所以无网格Galerkin法在处理边界条件和对区域积分时是不同于有限元的，它有其独特的处理方法，从加权残量法——Galerkin出发，推导出抛物型偏微分方程无网格Galerkin法的基本方程，并对影响无网格Galerkin法的主要因素进行探讨，给出了取得最佳效果的相应建议。

In this paper, combining the moving Kriging interpolation method and meshless local Petrov-Galerkin method, an improved meshless local Petrov-Galerkin method is presented, in which the Heaviside step function is used as test function over the local weak form.

本文将滑动Kriging插值方法与无网格局部Petrov-Galerkin法相结合，采用Heaviside分段函数作为局部弱形式的权函数，提出一种改进的无网格局部Petrov-Galerkin法，进一步将这种无网格法应用于位势问题，并推导出相应的离散方程。

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％。